KR20170009797A - Process for separating pollutant from wastewater and system thereof - Google Patents

Abstract

The present invention relates to a method for separating or collecting contaminants from wastewater. According to an embodiment of the present invention, the method, as a non-restrictive example to the extraction, involves the use of amine such as alkyl amine, wherein amine is randomly present as a form of solution. The contaminant compound retrieved from wastewater is able to be an organic compound which may affect the value of a chemical oxygen demand (COD). The present invention further relates to a system for separating or collecting contaminants from wastewater.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for separating contaminants from wastewater,

[001]. The present invention relates generally to the field of organic chemistry. In particular, the present invention includes a method for separating or recovering contaminants from wastewater. In one embodiment, the methods of the present invention involve the use of amines by non-limiting examples of selectively presenting an amine such as an alkylamine as a solution. The pollutant recovered from the wastewater may be an organic compound that contributes to chemical oxygen demand (COD). The present invention also relates to a system for separating or recovering contaminants from wastewater.

[002] One of the most common problems we face today is water pollution. Water is polluted for a variety of reasons, including industrialization, mining, sewage treatment, oil spills, marine dumping, urbanization, and so on. By various industries, harmful chemicals such as organic pollutants and inorganic contaminants flow into the water, which increases the concentration of harmful chemicals in the water. The concentration of organic chemicals such as terephthalic acid, p-toluic acid, isophthalic acid and the like in water can be measured by checking the chemical oxygen demand (COD) level of water.

[003]. Polymer grade terephthalic acid (1,4-benzene dicarboxylic acid) is the 25th largest chemical in the world. The US Amoco process is an established technology for producing polymer-grade terephthalic acid (about 75% of global production). It consists of liquid air oxidation of p-xylene with bromine as a renewable source of acetic acid as solvent, Co acetate as catalyst, Mn acetate and organic radicals. In the oxidation process, terephthalic acid is obtained with some impurities such as 4-formylbenzoic acid and p-toluic acid. The presence of only a fraction of 4-formylbenzoic acid in the product profile inhibits the properties of the final product (i.e., polyethylene terephthalate). This 4-formylbenzoic acid impurity is hydrogenated again with p-toluic acid in the presence of water at 250 DEG C under hydrogen pressure using a noble metal catalyst (Pd) on the carbon support. After crystallization of pure terephthalic acid from the mother liquor, the wastewater stream typically contains 4-formylbenzoic acid and p-toluic acid (4-methylbenzoic acid). These impurities, along with terephthalic acid, benzoic acid and acetic acid, were found to be the major organic contaminants in the wastewater produced in the oxidation and purification stages. 3-4 m ³ of wastewater with approximately 10 kg COD / m ³ per tonne of purified terephthalic acid (PTA) produced is produced.

[004] Currently, the most commonly used method for PTA wastewater treatment processes is two-stage anaerobic digestion followed by aerobic treatment. 'Anaerobic treatment' refers to a treatment process carried out without oxygen at a temperature range of 35-40 ° C. Anaerobic degradation of organic material is performed by a special mixing group of anaerobic microorganisms that utilize organic matter contained in raw water as a food and energy source. As a result of their normal growth cycle, microorganisms convert organic materials into gaseous by-products, called biogas / methane, and small amounts of new cell mass. However, the implementation of the anaerobic digestion process has substantial drawbacks, mainly due to its limited uptake. Anaerobic bacteria grow slowly and are more sensitive to changes in conditions. In order to achieve optimal performance, some operational parameters such as pH, temperature and the presence of toxic metals need to be tightly controlled. Despite methane production by anaerobic digestion, the high initial costs required to develop an anaerobic digester and the inherent complex problems associated with it are constantly hampering the economical development of PTA plant wastewater treatment.

[005] (AOP), supercritical water oxidation, UV-assisted ozonation (UV / O ₃ ), ozone assisted photochemical oxidation UV / O ₃ / H ₂ O ₂ ), photo-fenton oxidation (UV / H ₂ O ₂ / FeSO ₄ ), ozone assisted photo-fenton oxidation ₃ / H ₂ O ₂ / FeSO ₄ ) and radiation treatment with gamma radiation have been used in PTA wastewater treatment. In all the methods described above, the organic material is simply converted / oxidized to a simple molecule such as CO ₂ . However, the cost of treatment and the generation of toxic intermediates and sludge have been identified as a major problem limiting these methods by causing secondary contamination. In addition, conventional biodegradation methods can have a longer residence time if the initial COD of the effluent is high or if the wastewater contains organic acids that are not biodegradable

[006]. The present invention relates to a process for separating / recovering contaminants / organic compounds using an amine-based extractant, which efficiently recovers organic compounds that contribute to COD from aqueous solutions such as, but not limited to, wastewater To overcome all of these drawbacks observed in the prior art.

Summary of the Invention

[007] In some embodiments, the invention relates to a method for separating or recovering contaminants from wastewater.

[008] In some embodiments, the present invention relates to a method of separating contaminants from wastewater, the method comprising:

a) adjusting the temperature of the wastewater and optionally the pH;

b) contacting and mixing the wastewater from step a) with an alkylamine to obtain a mixture;

c) incubating the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater along with contaminants; And

d) separating the upper layer containing alkylamine with contaminants from the lower layer containing the treated wastewater

.

[009] In one embodiment, the contacting, mixing, incubation, or separation is performed at a temperature in the range of about 10 째 C to about 100 째 C, at a pressure of about 1 atm to about 10 atmospheres for about 1 minute to about 120 minutes.

[010]. In one embodiment, after adjusting the temperature and pH of the wastewater, the solid waste is separated from the wastewater in the solid separation unit (solid separation unit [F]).

[011]. In an exemplary embodiment, the solid waste is selected from the group comprising, but not limited to, precipitated organic acids and solid particulates or combinations thereof.

[012]. In one embodiment, the wastewater is selected from the group comprising aliphatic or aromatic hydrocarbons or derivatives thereof or combinations thereof; Wherein the hydrocarbon compound or derivative thereof is selected from the group comprising metal salts of organic acids and organic acids or combinations thereof.

[013] In one embodiment, the alkylamine is selected from a secondary amine or a tertiary amine or combinations thereof; Wherein said secondary alkylamine is an alkylamine having a C ₆ -C ₁₀ chain length; Said tertiary alkyl amine is an alkyl amine having a C ₆ -C ₁₀ chain length; Or a combination thereof.

[014] In one embodiment, the pH of the wastewater is adjusted. In an exemplary embodiment, the pH is reduced to a range of about 1.0 to about 4.0 at the original pH.

[015] In one embodiment, the alkylamine is; As a non-limiting example, a solution comprising a diluent such as chlorinated hydrocarbons, ketones, alcohols and halogenated aromatic solvents or combinations thereof, of which long chain hydrocarbon alcohols are preferred.

[016] In one embodiment, the weight ratio of alkylamine to wastewater is from about 0.5: 100 to about 1:20, preferably from about 0.5: 100 to about 3: 100.

[017] In some embodiments, the present invention is also directed to a system for separating and recovering contaminants from wastewater using an alkylamine optionally present as a solution.

[018] In some embodiments, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchanging unit [X] (heat exchanging unit [X]) suitable for receiving wastewater, wherein said at least one heat exchanging unit is set to regulate the temperature of the wastewater;

b) at least one mixing unit [M] fluidly connected to said at least one heat exchange unit [X], wherein said at least one mixing unit comprises at least one heat exchange unit Set to receive wastewater and alkyl amines to mix wastewater with alkyl amines); And

c) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], wherein said at least one settling unit comprises an alkylamine and wastewater from said at least one mixing unit And the mixture is allowed to settle to obtain a top layer comprising alkylamine with the contaminant and a bottom layer comprising the treated wastewater)

.

[019] In one embodiment of the invention, the system comprises at least one pH Adjustment Unit (pH Adjustment Unit) suitable for receiving wastewater, set between at least one heat exchange unit [X] and at least one mixing unit [M] , Wherein the at least one pH adjustment unit is set to adjust the pH of the wastewater.

[020]. In one embodiment of the invention, the system comprises at least one heat exchange unit [X] or at least one solid separation unit set between at least one pH adjustment unit [pH] and at least one mixing unit [M] Unit) [F]; The at least one solid separation unit is set to separate solid waste from the wastewater.

[021]. In one embodiment of the invention, at least one regeneration unit [ERU] is in fluid communication with at least one settling unit, wherein said at least one recycle unit is capable of removing contaminants Which is suitable for receiving an upper layer comprising an alkylamine together with an alkylamine and a contaminant.

[022] In one embodiment of the invention, at least one settling unit is in fluid communication with at least one biological treatment assembly (ASP) to receive wastewater from the settling unit.

[023] BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding and understanding of the present invention, reference will now be made, by way of example only, to the accompanying drawings, illustrating the invention in further detail. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments in further detail and illustrate various aspects of the present invention. In the accompanying drawings:
[024] FIG. 1 shows an exemplary embodiment of a process flow diagram for wastewater treatment according to the present invention.
[025]. Figure 2 shows an exemplary embodiment of a process flow diagram for wastewater treatment according to the present invention.
[026] 3 is a schematic view of a process for separating / recovering organic acids and reducing COD in PTA wastewater.
[027] 4A is a chemical reaction formula showing the formation of an acid-amine complex upon extraction of an organic acid using trioctylamine. 4B is a view showing a vial containing the obtained acid-amine complex. Figure 4c is a chemical reaction formula showing the regeneration of trioctylamine from an acid-amine complex by caustic neutralization. Figure 4d shows a process set to regenerate trioctylamine from an acid-amine complex by caustic neutralization. 4E is a view showing a chemical reaction formula for recovering an organic acid. Figure 4f shows a vial containing a metal salt such as sodium chloride and recovered organic acid. Figure 4g shows a wastewater sample (raw effluent) from a PTA plant and a wastewater sample treated with 2.5% (wt.) Trioctylamine at about 50 ° C as a fresh treatment and up to three And the result of the subsequent recycling process.
[028] 5 is a graph showing solubilities of organic acids (a) terephthalic acid, (b) benzoic acid and (c) p-toluic acid.
[029] 6 is a view showing dissociated forms and dissociated forms of organic acids.
[030] FIG. Figure 7 shows HPLC analysis results of organic acids in wastewater treated with alkylamines at various pHs. The x-axis is the pH used and the y-axis is the COD level in ppm.

DETAILED DESCRIPTION OF THE INVENTION

[031]. In order to overcome the non-limiting drawbacks described in the technical section under the background of the invention and to provide a simple and efficient process for the extraction or recovery of organic compounds, the present invention relates to a process for the preparation of organic compounds from aqueous solutions, Thereby providing a method for easy removal.

[032] FIG. The present invention relates to a method for separating contaminants from wastewater, the method comprising:

a) adjusting the temperature of the wastewater and optionally the pH;

b) contacting and mixing the wastewater from step a) with an alkylamine to obtain a mixture;

c) incubating the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater along with contaminants; And

d) separating the upper layer containing alkylamine with contaminants from the lower layer containing the treated wastewater

.

[033] FIG. The present invention also relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit (heat exchange unit) [X] (heat exchange unit [X]) suitable for receiving wastewater, wherein said at least one heat exchange unit is set to regulate the temperature of the wastewater;

b) at least one mixing unit (mixing unit) [M] fluidly connected to said at least one heat exchange unit [X], wherein said at least one mixing unit comprises at least one heat exchange unit Set to receive wastewater and alkyl amines to mix wastewater with alkyl amines); And

c) at least one settling unit (settling unit) [S] in fluid communication with said at least one mixing unit [M], wherein said at least one settling unit comprises an alkylamine and wastewater from said at least one mixing unit And the mixture is allowed to settle to obtain a top layer comprising alkylamine with the contaminant and a bottom layer comprising the treated wastewater)

.

[034] In one embodiment of the present invention, the wastewater of step a) is adjusted to have a temperature in the range of from about 10 째 C to about 100 째 C and a pH of from about 1.0 to about 4.0; Wherein such temperature regulation is carried out in a heat exchanger unit [X]; Adjustment of the pH is carried out in the pH adjustment unit [pH]; After adjusting the temperature and pH of the wastewater, the solid waste separated from the wastewater in step a) is separated from the solid separation unit [F].

[035] FIG. In another embodiment of the present invention, the contacting and mixing is carried out in the mixing unit [M]; The incubation of step c) is carried out in the settling unit [S]; The contacting, mixing, incubation, or separation is performed at a temperature of from about 10 캜 to about 100 캜, at a pressure of from about 1 atm to about 10 atm for a period of from about 1 minute to about 120 minutes.

[036] In another embodiment of the present invention, the top layer of step d) is separated from the bottom layer by decantation; Wherein the top layer of step d) is treated to recover the alkylamine and contaminants separately; Such treatment is carried out by techniques selected from solvent extraction, caustic neutralization, filtration and distillation or a combination thereof; Wherein the treatment is carried out in a unit selected from the group comprising a settling unit [S] and a regeneration unit (regeneration unit) [ERU] or a combination thereof; Wherein the lower layer of step d) is further treated in a biological treatment assembly (biological treatment assembly) [ASP] to obtain aqueous wastewater.

[037] In another embodiment of the present invention, the system comprises at least one pH adjusting unit [pH] suitable for receiving wastewater set between at least one heat exchange unit [X] and at least one mixing unit [M] , The at least one pH adjusting unit is set to adjust the pH of the wastewater.

[038] In another embodiment of the invention, the system comprises at least one heat exchange unit [X] or at least one solid separation unit [Solid] set between at least one pH adjustment unit [pH] and at least one mixing unit [M] Separation Unit) [F]; The at least one solid separation unit is set to separate solid waste from the wastewater.

[039] In another embodiment of the present invention, at least one regeneration unit [ERU] is in fluid communication with at least one settling unit, wherein the at least one regeneration unit is configured to remove alkylamine And is configured to separate the alkylamine and the contaminant.

[040] FIG. In another embodiment of the present invention, at least one settling unit is in fluid communication with at least one biological treatment assembly (ASP) to receive wastewater from the settling unit.

[041]. In another embodiment of the present invention, the at least one mixing unit comprises an injection port in fluid communication with the alkylamine source through the first passageway.

[042] In another embodiment of the present invention, the system comprises a bypass passage in fluid communication between at least one regeneration unit [ERU] and at least one settling unit [S]; And a first passageway.

[043] In another embodiment of the present invention, the system operates in a mode selected from the group comprising batch mode, semi-continuous mode and continuous mode or a combination thereof; The heat exchange unit [X] is a heat exchanger selected from the group consisting of a shell heat exchanger, a tubular heat exchanger and a flash evaporator or a combination thereof; The solid separation unit [F] is selected from the group comprising an anthropogenic filter, a bag filter and a press filter or a combination thereof; The mixing unit [M] is selected from the group comprising an agitated vessel reactor, a plug flow reactor, a static mixer, a jet mixer and a pump mixer or a combination thereof; The settling unit [S] is selected from the group comprising a gravitational settling vessel and a centrifugal settler or a combination thereof; The biological treatment assembly [ASP] is an activated sludge assembly; The regeneration unit [ERU] is selected from the group comprising a distillation column, a filtration unit and an extraction column or a combination thereof.

[044] In another embodiment of the present invention, the wastewater is selected from the group comprising aliphatic hydrocarbons or aromatic hydrocarbons or derivatives thereof or combinations thereof; Wherein the hydrocarbon compound or derivative thereof is selected from the group comprising metal salts of organic acids and organic acids or combinations thereof; Wherein the organic acid is selected from the group comprising benzoic acid, p-toluic acid, terephthalic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, 4-methylbenzoic acid, isophthalic acid and orthophthalic acid or combinations thereof; Wherein the cation in the metal salt of the organic acid is selected from the group comprising sodium, magnesium and potassium or a combination thereof; The anion in the metal salt of the organic acid is selected from the group comprising terephthalate, acetate, benzoate, isophthalate, trimethylate, methylbenzoate, phthalate, carboxybenzoate or combinations thereof.

[045] FIG. In another embodiment of the present invention, the wastewater is selected from the group comprising industrial wastewater, purified terephthalic acid (PTA) wastewater, petrochemical wastewater, pharmaceutical industry wastewater and isophthalic acid wastewater or combinations thereof; Wherein the alkylamine is selected from a secondary amine or a tertiary amine or combinations thereof; Wherein the secondary alkyl amine is a C6-C10 chain length alkyl amine; Tertiary alkyl amines include C6-C10 chain length alkyl amines; Or a combination thereof.

[046] In another embodiment of the present invention, the alkylamine is selected from the group comprising trihexylamine and trioctylamine or combinations thereof.

[047] In another embodiment of the present invention, the alkylamine is present as a solution, wherein the solution is a diluent selected from the group consisting of chlorinated hydrocarbons, ketones, alcohols and halogenated aromatic solvents or combinations thereof, preferably long chain hydrocarbons Alcohol; The weight ratio of alkylamine to wastewater is preferably from about 0.5: 100 to about 1: 20, and more preferably from about 0.5: 100 to about 3: 100.

[048] In another embodiment of the present invention, the solid waste is selected from precipitated organic acids and solid particulate materials or combinations thereof.

[049]. In this specification, the terms "method" and "process" have the same scope and meaning and are used interchangeably.

[050]. As used herein, the term " wastewater " refers to water produced as a by-product of industrial activity or commercial activity. In one embodiment, the wastewater used in the present invention is in a treated or untreated form.

[051]. As used herein, the terms " PTA wastewater "," PTA plant wastewater " or " purified terephthalic acid wastewater " refer to wastewater generated from the PTA manufacturing industry.

[052] As used herein, the term " pollutant " refers to undesirable material (s) or contaminant (s) present in the wastewater. In one embodiment, the undesirable substance (s) or soil (s) may be harmful to the organism or environment or apparatus or to any industrial / commercial installation. In one embodiment of the invention, the contaminants are present in a form selected from the group comprising solids, liquids and gases or combinations thereof.

[053] As used herein, the term " regulating the temperature " means increasing, lowering or maintaining the temperature.

[054] As used herein, the term " controlling pH " means increasing, decreasing or maintaining pH.

[055]. In this specification, the terms " modulating " and " adjusting " have the same scope and meaning and are used interchangeably.

[056] In this specification, the terms effluent and wastewater have the same scope and meaning and are used interchangeably.

[057] In this specification, 'g' and 'gm' are used interchangeably to indicate gram units.

[058] In this specification, the terms 'organic compound' and 'contaminant' have the same scope and meaning and are used interchangeably.

[059] The present invention relates to a process for the recovery of organic compounds from wastewater by treating wastewater or using amines such as alkyl amines by using amines such as alkyl amines.

[060] FIG. In one embodiment, an amine such as an alkylamine used to treat wastewater or to recover organic compounds from wastewater is optionally presented as a solution.

[061]. In one embodiment, the invention utilizes a reactive liquid-liquid extraction using an extractant such as an alkylamine. In one embodiment, the process of the present invention provides valuable organic compounds at high selectivity and improved recovery. The extraction solvent in the organic phase reacts with the organic compound in the aqueous phase and the reaction complex thus formed is dissolved in the active diluent organic phase.

[062] In one non-limiting embodiment, wastewater includes, but is not limited to, PTA factory wastewater, industrial wastewater, petrochemical wastewater, pharmaceutical industry wastewater and isophthalic acid wastewater, or combinations thereof.

[063] In one embodiment of the invention, the organic compounds extracted from the wastewater include aliphatic or aromatic compounds or derivatives thereof or combinations thereof.

[064] In one non-limiting embodiment of the present invention, the waste water comprises pollutants selected from the group comprising organic compounds / aliphatic hydrocarbons or aromatic hydrocarbons or derivatives thereof or combinations thereof. In one embodiment of the invention, the wastewater comprises an organic compound selected from the group comprising an organic acid or a corresponding metal salt thereof.

[065] In one non-limiting embodiment of the invention, the organic compounds / contaminants in the wastewater are benzoic acid, p-toluic acid, terephthalic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, 4- methylbenzoic acid, isophthalic acid and orthophthalic acid or Organic acids selected from the group consisting of combinations thereof.

[066] In one embodiment of the present invention, the organic compounds / contaminants in the wastewater are selected from the group consisting of benzoic acid, p-toluic acid, terephthalic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, 4-methylbenzoic acid, isophthalic acid and orthophthalic acid, ≪ / RTI >

[067]. In one embodiment of the invention, the cation in the metal salt of the organic acid is selected from the group comprising sodium, magnesium and potassium or a combination thereof; The anion in the metal salt of the organic acid is selected from the group comprising terephthalate, acetate, benzoate, isophthalate, trimethylate, 4-methylbenzoate, phthalate and 4-carboxybenzoate or combinations thereof.

[068] In one non-limiting embodiment of the invention, the metal salt of the organic acid is selected from the group consisting of sodium terephthalate, sodium acetate, sodium benzoate, sodium isophthalate, sodium-trimethylate, 4- methylsodium benzoate, sodium phthalate, Magnesium acetate, magnesium benzoate, magnesium isophthalate, magnesium-trimethylate, 4-methyl magnesium benzoate, magnesium phthalate, 4-carboxymagnesium benzoate, potassium terephthalate, potassium acetate, potassium benzoate, Potassium isophthalate, potassium-trimethylate, 4-methylpotassium benzoate, potassium phthalate and 4-carboxy potassium benzoate, or combinations thereof.

[069]. In one non-limiting embodiment of the present invention, the effluent is preferably PTA effluent.

[070] In one embodiment, the PTA factory wastewater comprises organic acids such as terephthalic acid, isophthalic acid, acetic acid, para-toluic acid, benzoic acid, 4-carboxybenzoic acid, 4-methylbenzoic acid and orthophthalic acid; And a metal salt of the organic acid, wherein the cation in the metal salt is selected from a non-limiting group including sodium, magnesium, and potassium; or combinations thereof.

[071]. In one embodiment, the process of the present invention is for treating wastewater by extracting various organic compounds / contaminants that contribute to COD using an amine based extraction solvent. In one exemplary embodiment, the amine-based extraction solvent is an alkylamine.

[072] In one embodiment, the carboxylic acid involved in the organic acid upon addition of the alkylamine to the wastewater is a complex that is termed an acid-amine complex with an alkylamine if the organic acid is in an un-dissociated form . The optimum pH for the separation of the formed complexes is based on the pK _a (acid dissociation constant) of each organic acid present in the wastewater.

The acid dissociation constant (pKa) of any organic acid at 25 ° C is shown in Table 1. At higher pH values, organic acids are usually dissociated and therefore not suitable for reactive extraction, in which case ion exchange separation is used. In another embodiment, adjusting the pH of the organic acid solution below its pKa results in the organic acid being in its undissociated state, making it more suitable for separation by reactive extraction (FIG. 6). In one embodiment of the present invention, reactive extraction of organic acids and salts thereof is possible if they are in a non-dissociated form (which occurs at low pH conditions). In one embodiment of the invention, if the pH < pK _a , the organometallic salt is converted to its organic acid (undissociated form). In another embodiment of the present invention, the metal salt is converted to its corresponding organic acid by lowering the pH, which forms a complex with the alkylamine to form an acid-amine complex.

Organic acid PKa at 25 &lt; 0 &gt; C Terephthalic acid 3.51 4-Carboxybenzoic acid 1.76 Benzoic acid 4.19 Orthophthalic acid 2.89 and 5.51 Trimellitic acid 2.721 Paratoluic acid 4.36 Isophthalic acid 3.7 and 4.6

[073] In one embodiment of the invention, the pH of the wastewater is adjusted. In another embodiment, the pH of the wastewater is adjusted to a range from about 1.0 to about 4.0. In another embodiment, the pH of the wastewater is adjusted to a range of from about 1.0 to about 3.5. In another embodiment, the pH of the wastewater is adjusted to a range of from about 1.0 to about 3.0. In another embodiment, the pH of the wastewater is adjusted to a range from about 1.0 to about 2.5. In another embodiment, the pH of the wastewater is adjusted to a range of from about 2.0 to about 3.0. In another embodiment, the pH of the wastewater is adjusted to a range of from about 2.0 to about 2.5. In another embodiment, the pH is adjusted / reduced by using a Bronsted / positive asset such as HCl as a non-limiting example.

[074]. In an exemplary embodiment, the pH of the wastewater is adjusted by decreasing from the original pH to a range of from about 2.0 to about 2.5.

[075]. In one non-limiting embodiment of the invention, the alkylamines are selected from secondary amines or tertiary amines or combinations thereof. In one embodiment, the secondary alkylamine is C ₆ -C ₁₀ Chain length, preferably C ₆ -C ₈ An alkylamine having a chain length; The tertiary alkylamine is C ₆ -C ₁₀ A chain length, preferably an alkylamine having a C ₆ -C ₈ chain length; Or a combination thereof.

[076] In one embodiment, a secondary amine or a tertiary amine is preferably a C ₆ -C ₁₀ alkyl chain comprises a C ₆ -C ₈ alkyl chain length.

[077]. In one exemplary embodiment of the invention, the alkylamine is selected from the group comprising trihexylamine and trioctylamine or combinations thereof.

In another exemplary embodiment of the present invention, the alkylamine is Alamine® 336 (containing about 95% TOA and about 5% C ₅ alkyl chain secondary amine).

[079] In one embodiment, the amine used in the process is a tertiary amine having an excellent extraction rate for carboxylic acid. However, because of the high viscosity and corrosiveness, tertiary amines are introduced in the form of solutions in organic diluents.

In one embodiment of the present invention, an amine such as an alkylamine is present in the solution, wherein the solution is not limited to a diluent such as, but not limited to, saline hydrocarbons, ketones, halogenated aromatic solvents, long chain hydrocarbon alcohols, Molecular weight alcohols, or combinations thereof. In a preferred embodiment, the diluent is a long chain hydrocarbon alcohol. In one exemplary embodiment, the diluent is octanol.

In another embodiment, the diluent with a functional group significantly affects the extraction behavior of the amine. In another embodiment, the functional groups in the diluent are selected from, but are not limited to, salified hydrocarbons, ketones, alcohols, halogenated aromatic solvents, or combinations thereof.

[082] In one non-limiting embodiment, the organic diluent can increase the solvation of the acid-amine complex because of its polarity.

In one embodiment, the weight ratio of alkylamine to wastewater used in the process of the present invention is from about 0.5: 100 (ie, from about 1: 200) to about 1:20, preferably from about 0.5: 100 to about 3 : 100, more preferably from about 0.5: 99.5 to about 1: 30.

[084] In one embodiment, the ratio of alkylamine to wastewater increases the extraction of organic compounds / contaminants by the method of the present invention. If it exceeds this range, the extraction efficiency of the organic compound decreases.

[085] In one embodiment of the present invention, the extraction solvent used is an alkylamine which is not an ionic liquid. Amine-based ionic liquids are weak ionic liquids that can dissolve in water and impart strong acidity to water, which is undesirable. In one embodiment of the invention, the use of alkylamines as the extraction solvent, such as, but not limited to TOA, is more economical than using an ionic liquid as the extraction solvent.

In one embodiment of the present invention, the recovery of the extraction solvent and the recovery of contaminants such as organic acids and metal salts thereof from wastewater are very efficient. In one embodiment, the process of the present invention extracts contaminants such as organic acids (aliphatic or aromatic) and their metal salts with high efficiency.

[087] In another embodiment, the alkylamine or organic phase alkylamine is regenerated with high accuracy and reused to recover additional organic acids from the wastewater / effluent.

In a non-limiting embodiment, the secondary or tertiary alkyl amine is regenerated through a caustic wash, so that the acid-amine complex may be a secondary or tertiary amine and a sodium salt of a carboxylic acid, And is decomposed into the sodium salt of terephthalic acid. The organoalkylamine is then separated by a decantation process.

[089] In one embodiment of the invention, the extraction solvent (alkylamine) is regenerated into an organic phase containing an acid-amine complex by caustic wash.

In one embodiment, the acid-amine complexes thus formed are separated by techniques such as, but not limited to, phase separation, precipitation, gravity separation, centrifugation, or combinations thereof. In one non-limiting exemplary embodiment, the solvated acid-base complex is present in the organic diluent / medium.

[091] In a further embodiment, the reactive liquid-liquid extraction method of the present invention replaces or eliminates the costly and time consuming anaerobic digestion process carried out in a wastewater treatment, such as a PTA wastewater treatment process. In an alternative embodiment, the COD concentration of wastewater / effluent after extraction with amine is suitable for feeding to an activated sludge aerobic treatment process to further reduce the COD concentration according to the required criteria. In a non-limiting embodiment, the method is followed by an aerobic treatment.

[092] In a preferred embodiment, the method of extracting organic compounds from wastewater comply with emission standards by reducing / lowering the COD concentration.

[093] Chemical Oxygen Demand (COD) represents the amount of the oxidizing (oxidisable) organic compounds present in the water (or water pipiem be displayed in milligrams per liter). The higher the amount of contaminants in the sample, the higher the chemical oxygen demand. In one embodiment, the COD is a measure of water quality and represents the amount of oxidizing chemical contaminants present in the wastewater. Thus, in one embodiment, the COD reduction of a wastewater sample after treatment with an amine extraction solvent is used to calculate percent extraction of contaminants such as organic compounds from the sample.

In one embodiment of the present invention, the COD concentration of water is detected using normal laboratory analysis methods.

[095] In an exemplary embodiment of the invention, the COD concentration of water is detected using the potassium dichromate method.

In one embodiment of the present invention, the COD concentration of the wastewater is reduced by the method of the present invention from about 8000 to 10,000 ppm, from about 300 to about 2000 ppm, and more preferably from about 500 to 1200 ppm.

In a preferred embodiment, during the extraction of contaminants such as organic compounds from wastewater, the process lowers / reduces the COD concentration of the wastewater.

In one embodiment, the process of the present invention reduces the amount of COD in the wastewater / effluent to about 70-95% by recovering the organic acid from the PTA effluent, and the recovery rate of the organic acid is lower than that of the terephthalic acid Thereby increasing the overall production yield.

In one embodiment of the present invention, the rate of extraction of contaminants from wastewater is from about 60% to about 95%, preferably from about 70% to about 90%, relative to the weight of initial contaminants present in the wastewater And preferably in the range of about 75% to about 85%.

[0100] In another embodiment, the water treated after the third water treatment process produces less sludge during the aerobic process.

[0101] In another embodiment, extracted / recovered organic acids such as, but not limited to, p-toluic acid and 4-formylbenzoic acid are recycled to the main oxidation reaction of p-xylene.

[0102] In another embodiment of the present invention, the COD contributing to the organic acid compound is recovered as an aqueous phase containing an acid such as HCl and a metal salt of an organic acid (eg, sodium salt of terephthalic acid, but not limited thereto); As a result, the net process yield slightly increases.

[0103] In one embodiment, the treated water COD is suitable for supplying to the activated sludge aerobic treatment process to further reduce the COD concentration of the wastewater / effluent.

[0104] The present invention also relates to a method for extracting, recovering, or separating organic compounds / contaminants from an aqueous solution, such as, but not limited to, wastewater, comprising the following actions:

a) letting the aqueous solution at a high temperature pass through a heat exchange unit to lower the temperature and adjust the pH; Facilitating precipitation of solids and separating them from aqueous wastewater solution;

b) mixing the amine selectively present in the solution with the aqueous wastewater obtained in the above step, and then separating the aqueous wastewater layer and the amine layer containing the recovered organic compound;

c) recycling and / or regenerating the separated amine layer; The separated aqueous wastewater layer having undergone an aerobic treatment assembly;

[0105] In one embodiment, the present invention relates to a method for separating contaminants from wastewater, the method comprising the following actions:

a) adjusting the temperature of the wastewater and optionally the pH;

b) contacting and mixing the wastewater obtained in step a) with an alkylamine to obtain a mixture;

c) incubating the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater along with contaminants; And

d) separating the upper layer containing alkylamine with contaminants from the lower layer containing treated wastewater.

[0106] In another embodiment, the present invention relates to a method for separating contaminants from wastewater, comprising the following actions:

a) adjusting the temperature of the wastewater and optionally the pH;

b) contacting and mixing the wastewater obtained in step a) with an alkylamine to obtain a mixture;

c) incubating the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater along with contaminants; And

d) separating the upper layer containing alkylamine with contaminants from the lower layer containing treated wastewater.

[0107] In one embodiment, the present invention relates to a method for separating contaminants from wastewater, comprising the following actions:

a) adjusting the temperature of the wastewater and optionally the pH; Separating the solid waste from the wastewater after temperature and pH adjustment;

b) contacting and mixing the wastewater obtained in step a) with an alkylamine to obtain a mixture;

c) incubating the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater along with contaminants; And

d) separating the upper layer containing alkylamine with contaminants from the lower layer containing treated wastewater.

[0108] In one embodiment, the amine is an alkylamine selected from a secondary amine or tertiary amine having a C ₆ -C ₁₀ chain length. In one embodiment, the alkylamine and aqueous wastewater optionally present in the solution has a temperature in the range of from about 10 째 C to about 100 째 C, preferably from about 30 째 C to about 80 째 C; In a pressure range of from about 1 atmosphere to about 10 atmospheres, preferably from about 1 atmosphere to about 2 atmospheres; For a duration of from about 1 minute to about 120 minutes, preferably from about 20 minutes to about 50 minutes.

[0109] In another embodiment, the ratio of amine present in the aqueous wastewater versus solution ranges from about 100: 0.5 to about 20: 1, preferably from about 100: 0.5 to about 100: 3.

[0110] In another embodiment, the extracted / recovered organic oxide / contaminant can be, but is not limited to, one or more organic acids, such as terephthalic acid, p-toluic acid, 4-methylbenzoic acid, 4-carboxybenzoic acid, trimellitic acid, Acetic acid, isophthalic acid and orthophthalic acid; Metal salts of these organic acids and various organic compounds present in the wastewater.

In one embodiment of the invention, in step a), the wastewater is heated to a temperature in the range of from about 10 ° C to about 100 ° C, a pH of from about 1.0 to about 4.0, preferably from about 1.5 to about 3.5, To about 3.0; Wherein the temperature regulation is performed in the heat exchange unit [X]; The pH adjustment is controlled in the pH adjustment unit [pH]; The solid waste is separated from the wastewater in solid separation unit [F] in step a). In one embodiment of the invention, said contacting and mixing is carried out in a mixing unit [M]; The incubation of step c) is carried out in a settling unit [S]; Wherein contacting, mixing, incubation, or separation is performed at a temperature in the range of from about 10 째 C to about 100 째 C, at a pressure in the range of from about 1 atmosphere to about 10 atmospheres, for a period ranging from about 1 minute to about 120 minutes. In one embodiment of the present invention, the top layer of step d) is separated from the bottom layer by decantation; Wherein the upper layer of step d) is treated to recover alkylamine and contaminants respectively; Wherein the treatment is carried out through a technique selected from solvent extraction, caustic neutralization, filtration and distillation, or a combination thereof; Wherein the treatment is carried out in a unit selected from the group consisting of a precipitation unit [S] and a regeneration unit [ERU] or a combination thereof; Wherein the lower layer of step d) is further treated in at least one biological treatment assembly [ASP] to obtain aqueous wastewater. The present invention also relates to systems for the extraction and recovery of organic compounds from wastewaters, including, but not limited to, aqueous solutions, including, but not limited to, PTA / isophthalic acid wastewater using amines, Wherein the amine is optionally present in solution.

[0112] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one mixing unit [M] in fluid communication with at least one heat exchange unit [X], wherein at least one mixing unit is adapted to receive wastewater and alkylamine from at least one heat exchange unit [X] At least one mixing unit [M] constituted to mix wastewater and alkylamine; And

c) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit receives a mixture comprising wastewater and an alkylamine from at least one mixing unit And at least one settling unit [S] wherein the mixture is allowed to settle to obtain a lower layer comprising an upper layer comprising alkylamine and a treated wastewater together with a contaminant.

[0113] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one mixing unit [M] in fluid communication with at least one heat exchange unit [X], wherein at least one mixing unit is adapted to receive wastewater and alkylamine from at least one heat exchange unit [X] At least one mixing unit [M] constituted to mix wastewater and alkylamine; And

c) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit receives a mixture comprising wastewater and an alkylamine from at least one mixing unit , At least one settling unit [S] wherein the mixture is allowed to settle to obtain a lower layer comprising an upper layer containing alkylamine and treated wastewater together with a contaminant; And

d) at least one regeneration unit [ERU] in fluid communication with at least one settling unit, wherein at least one regeneration unit is adapted to receive an upper layer comprising alkylamine with contaminants from at least one settling unit And is configured to separate alkylamine and contaminants.

[0114] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one mixing unit [M] in fluid communication with at least one heat exchange unit [X], wherein at least one mixing unit is adapted to receive wastewater and alkylamine from at least one heat exchange unit [X] At least one mixing unit [M] constituted to mix wastewater and alkylamine; And

c) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit receives a mixture comprising wastewater and an alkylamine from at least one mixing unit , At least one settling unit [S] wherein the mixture is allowed to settle to obtain a lower layer comprising an upper layer containing alkylamine and treated wastewater together with a contaminant; And

d) at least one biological treatment assembly (ASP) in fluid communication with at least one settling unit for obtaining wastewater from the settling unit.

[0115] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one mixing unit [M] in fluid communication with at least one heat exchange unit [X], wherein at least one mixing unit is adapted to receive wastewater and alkylamine from at least one heat exchange unit [X] At least one mixing unit [M] constituted to mix wastewater and alkylamine; And

c) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit contains a mixture comprising wastewater and an alkylamine from at least one mixing unit, At least one settling unit [S] in which the mixture is allowed to settle to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants; And

d) at least one regeneration unit [ERU] in fluid communication with at least one settling unit, wherein at least one regeneration unit is adapted to receive an upper layer comprising alkylamine with contaminants from at least one settling unit And is configured to separate alkylamine and contaminants; at least one recycling unit (ERU); And

e) at least one biological treatment assembly (ASP) in fluid communication with at least one settling unit for obtaining wastewater from the settling unit.

[0116] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one pH adjustment unit [pH] for containing wastewater between at least one heat exchange unit [X] and at least one mixing unit [M], wherein at least one pH adjustment unit controls the pH of the wastewater At least one pH adjusting unit [pH];

c) at least one mixing unit [M] in fluid communication with at least one pH adjusting unit [pH], wherein at least one mixing unit is configured to accommodate wastewater and alkylamine from at least one pH adjusting unit And is configured to mix the wastewater and the alkylamine; at least one mixing unit [M]; And

d) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit contains a mixture comprising waste water and an alkylamine from at least one mixing unit And at least one settling unit [S] wherein the mixture is allowed to settle to obtain a lower layer comprising an upper layer comprising alkylamine and a treated wastewater together with a contaminant.

[0117] In one embodiment, the present invention relates to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] for receiving wastewater, wherein at least one heat exchange unit is configured to regulate the temperature of the wastewater;

b) at least one solid separation unit [F] constructed between at least one heat exchange unit [X] and at least one mixing unit [M], wherein at least one solid separation unit is configured to separate solid waste from the waste water At least one solid separation unit [F];

c) at least one mixing unit [M] in fluid communication with at least one solid separation unit [F], wherein at least one mixing unit is configured to accommodate wastewater and alkylamine from at least one solid separation unit And is configured to mix the wastewater and the alkylamine; at least one mixing unit [M]; And

d) at least one settling unit [S] in fluid communication with at least one mixing unit [M], wherein at least one settling unit contains a mixture comprising waste water and an alkylamine from at least one mixing unit And at least one settling unit [S] wherein the mixture is allowed to settle to obtain a lower layer comprising an upper layer comprising alkylamine and a treated wastewater together with a contaminant.

[0118] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjustment unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and at least one solid separation unit [F] at least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one solid separation unit [F] constituted between at least one pH adjustment unit [pH] and said at least one mixing unit [M], said at least one solid separation unit being configured to separate solid waste from said wastewater One or more solid separation units [F];

d) at least one mixing unit [M] in fluid communication with said at least one solid separation unit [F], said at least one mixing unit being configured to receive wastewater and an alkylamine from said at least one pH adjustment unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine; And

e) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, Wherein at least one settling unit [S] is configured to allow sedimentation of the mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with a contaminant,

.

[0119] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjusting unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and said at least one mixing unit [M] At least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one mixing unit [M] in fluid communication with said at least one pH adjusting unit [pH], wherein said at least one mixing unit is configured to receive wastewater and an alkylamine from said at least one pH adjusting unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine;

d) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants; And

e) at least one regeneration unit [ERU] in fluid communication with said at least one settling unit, said at least one regeneration unit being adapted to receive an upper layer comprising alkylamine with contaminants from said at least one settling unit , At least one recycling unit (ERU) configured to separate said alkylamine and said contaminant,

.

[0120] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjusting unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and said at least one mixing unit [M] At least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one mixing unit [M] in fluid communication with said at least one pH adjusting unit [pH], wherein said at least one mixing unit is configured to receive wastewater and an alkylamine from said at least one pH adjusting unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine;

d) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants; And

e) one or more biological treatment assemblies (ASP) in fluid communication with the at least one settling unit for obtaining the wastewater from the settling unit,

.

[0121] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjusting unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and said at least one mixing unit [M] At least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one mixing unit [M] in fluid communication with said at least one pH adjusting unit [pH], wherein said at least one mixing unit is configured to receive wastewater and an alkylamine from said at least one pH adjusting unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine;

d) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants;

e) at least one regeneration unit [ERU] in fluid communication with said at least one settling unit, said at least one regeneration unit being adapted to receive an upper layer comprising alkylamine with contaminants from said at least one settling unit At least one regeneration unit (ERU) configured to separate the alkylamine and the contaminant; And

f) one or more biological treatment assemblies (ASP) in fluid communication with one or more settling units for obtaining the wastewater from the settling unit,

.

[0122] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjustment unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and at least one solid separation unit [F] at least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one solid separation unit [F] constituted between said at least one pH adjustment unit [pH] and said at least one mixing unit [M], said at least one solid separation unit separating solid waste from said wastewater One or more solid separation units [F] constituted;

d) at least one mixing unit [M] in fluid communication with said at least one solid separation unit [F], said at least one mixing unit being configured to receive wastewater and an alkylamine from said at least one pH adjustment unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine;

e) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants; And

f) at least one regeneration unit [ERU] in fluid communication with said at least one settling unit, said at least one regeneration unit being adapted to receive an upper layer comprising alkylamine with contaminants from said at least one settling unit , At least one recycling unit (ERU) configured to separate said alkylamine and said contaminant,

.

[0123] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjustment unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and at least one solid separation unit [F] at least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one solid separation unit [F] constituted between said at least one pH adjustment unit [pH] and said at least one mixing unit [M], said at least one solid separation unit separating solid waste from said wastewater One or more solid separation units [F] constituted;

d) at least one mixing unit [M] in fluid communication with said at least one solid separation unit [F], said at least one mixing unit being configured to receive wastewater and an alkylamine from said at least one pH adjustment unit, At least one mixing unit [M] configured to mix the water and the alkylamine;

e) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants; And

f) one or more biological treatment assemblies (ASP) in fluid communication with the at least one settling unit for obtaining the wastewater from the settling unit,

.

[0124] In one embodiment, the present disclosure is directed to a system for separating contaminants from wastewater, the system comprising:

a) at least one heat exchange unit [X] adapted to receive wastewater, said heat exchange unit comprising at least one heat exchange unit [X] configured to regulate the temperature of said wastewater;

b) at least one pH adjustment unit [pH] adapted for receiving wastewater, constituted between at least one heat exchange unit [X] and at least one solid separation unit [F] at least one pH adjusting unit [pH] configured to adjust the pH;

c) at least one solid separation unit [F] constituted between said at least one pH adjustment unit [pH] and said at least one mixing unit [M], said at least one solid separation unit separating solid waste from said wastewater One or more solid separation units [F] constituted;

d) at least one mixing unit [M] in fluid communication with said at least one solid separation unit [F], said at least one mixing unit being configured to receive wastewater and an alkylamine from said at least one pH adjustment unit, At least one mixing unit [M] configured to mix the wastewater and the alkylamine;

e) at least one settling unit [S] in fluid communication with said at least one mixing unit [M], said at least one settling unit receiving a mixture comprising said wastewater and said alkylamine from said at least one mixing unit, One or more settling units [S] being configured to be capable of settling said mixture to obtain a bottom layer comprising an upper layer comprising alkylamine and treated wastewater together with contaminants;

f) at least one regeneration unit [ERU] in fluid communication with said at least one settling unit, said at least one regeneration unit being adapted to receive an upper layer comprising alkylamine with contaminants from said at least one settling unit At least one regeneration unit (ERU) configured to separate the alkylamine and the contaminant; And

g) one or more biological treatment assemblies (ASP) in fluid communication with said at least one settling unit for obtaining said wastewater from said settling unit,

.

[0125] In one embodiment of the disclosure, the at least one mixing unit comprises an inlet which is in fluid communication with an alkylamine source through a first passage.

[0126] In one embodiment of the disclosure, the system comprises at least one of the at least one regeneration unit [ERU] and the at least one settling unit [S]; And a bypass passage in fluid communication between the first passages.

[0127] In one non-limiting embodiment, the system operates in either a batch mode or a semi-continuous mode or a continuous mode.

[0128] In one embodiment, the separation / recovery of the organic compound from an aqueous solution such as, but not limited to, wastewater can be achieved by removing an aqueous solution, such as wastewater, from the storage tank [St] To a regeneration unit [PH], a solid separation unit [F], a mixing unit [M], a settling unit [S], an aerobic treatment assembly [ASP] and a regeneration unit [ERU] or any combination thereof.

[0129] Figure 1 is an exemplary implementation of this disclosure showing a block diagram of the system [100] for separating / recovering organic compounds / contaminants from an aqueous solution such as, but not limited to, wastewater. The system operates in either batch or semi-continuous or continuous mode. The storage tank [St] stores wastewater such as PTA / isophthalic acid wastewater from which the organic compounds are to be extracted or recovered. The storage tank is in fluid communication with the heat exchange unit [X] via stream 1. The stream 1 carrying the wastewater, for example the PTA wastewater stored in the storage tank [St], to the heat exchange unit [X] is at a high temperature of about 150 ° C. In the heat exchange unit, the wastewater is cooled to room temperature in the range of about 30 캜 to about 80 캜. In one embodiment, the heat exchange unit is selected from, but is not limited to, a shell heat exchanger, a tube heat exchanger, and a flash evaporator, or any combination thereof. In one non-limiting embodiment, at such prevailing temperatures ranging from about 40 ° C to about 60 ° C, solid (but not limited to) terephthalic acid and paratoluic acid are precipitated. The heat exchange unit is in fluid communication with the pH adjustment unit [pH] to reduce the pH of the wastewater to a range of from about 1.0 to about 4.0, preferably from 2.0 to about 3.5, and more preferably from about 2.0 to about 2.5 do. In one embodiment, the pH adjustment is performed with the addition of (but not limited to) an acid such as a Bronsted / positive amber such as, for example, hydrochloric acid (HCl). In one embodiment, the pH adjustment unit is in fluid communication with the mixing unit [M] via stream 3. If desired, the extract present as a solution, i. E. Alkylamine, is injected into the mixing unit through stream 4. The alkylamine and wastewater streams from streams 4 & 3, respectively, are mixed in the mixing unit [M]. In one embodiment, the mixing unit may be a stirred vessel reactor, a plug flow reactor, a static mixer, a jet mixer, a pump mixer, &Lt; / RTI &gt; or any combination thereof. The streams flow into the mixing unit [M], wherein the temperature in M ranges from about 10 [deg.] C to about 100 [deg.] C and the pressure is from about 1 to about 10 atm. In another embodiment, the weight ratio of PTA wastewater to alkyl amine solution ranges from about 100: 0.5 to about 20: 1. The time required for sufficient mixing / extraction varies from about 1 minute to about 120 minutes. In one embodiment, organic compounds such as terephthalic acid, p-toluic acid, 4-methylbenzoic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, isophthalic acid, orthophthalic acid, metal salts of such organic acids, But are not limited to); And other various organic compounds present in the PTA wastewater stream are extracted / withdrawn into the alkylamine solution. In one embodiment, the outlet of the mixing unit [M] enters directly into the settling unit [S], where the separation of the alkylamine solution from the aqueous wastewater stream is effected. In one embodiment, the settling unit [S] includes, but is not limited to, a gravity settling vessel and a centrifuge settler or a combination thereof. The mixing unit and the settling unit may be present in combination or individually in the system. The separated / treated aqueous wastewater (bottom layer) is collected separately via stream 6; Which is in fluid communication with the aerobic treatment assembly [ASP].

[0130] In one embodiment, the separated / treated wastewater stream 6 is pH-neutrally neutralized by known aerobic / activated sludge processes before being sent for further removal of COD caused by unextracted organic compounds . The aqueous stream produced from the aerobic treatment assembly is discharged through stream 9. The sludge produced from the aerobic treatment assembly is discharged through stream 10.

[0131] In one embodiment, the upper alkylamine layer is separated via stream 7 and is referred to as recycled alkylamine, which is sent through stream 5 for further mixing with a new PTA waste water stream in the mixing unit; Alkylamine solutions are just as they can be recycled. The stream 7 connects the sedimentation unit [S] with the regeneration unit [ERU]. In one embodiment, the regeneration unit is the extract regeneration unit. A small fraction of the alkylamine solution is regenerated by caustic solution (NaOH). The regenerated alkylamine solution stream 8 may be used for further extraction of contaminants / organic compounds from wastewater. The stream 8 connects the playback unit [ERU] with the stream 4, which in turn is connected to the mixing unit.

[0132] 2 is an exemplary embodiment of the present disclosure showing a block diagram of a system 200 for separating / recovering organic compounds / contaminants from an aqueous solution such as wastewater, but not exclusively. The system operates in either batch or semi-continuous or continuous mode. The storage tank [St] stores wastewater, such as the PTA / isophthalic acid wastewater from which the organic compound is to be extracted or recovered. The storage tank is in fluid communication with the heat exchange unit [X] via stream 1. The stream 1, which is stored in the waste water, for example, the storage tank [St] and carries the PTA wastewater to the heat exchange unit [X], is at a high temperature of about 150 ° C. In the heat exchange unit, the wastewater is cooled to room temperature in the range of about 30 degrees Celsius to about 80 degrees Celsius. In one embodiment, the heat exchange unit is selected from, but is not limited to, a shell heat exchanger, a tube heat exchanger, and a flash evaporator, or any combination thereof. In one non-limiting embodiment, at such prevailing temperatures ranging from about 40 ° C to about 60 ° C, solid (but not limited to) terephthalic acid and paratoluic acid are precipitated. The heat exchange unit is in fluid communication with the pH adjustment unit [pH] to reduce the pH of the wastewater to a range of from about 1.0 to about 4.0, preferably from 2.0 to about 3.5, and more preferably from about 2.0 to about 2.5 do. In one embodiment, the pH adjustment is performed with the addition of (but not limited to) an acid such as a Bronsted / positive amber such as, for example, hydrochloric acid (HCl).

[0133] The pH adjustment unit is in fluid communication with the solid separation unit [F] via stream 11, which helps to remove (for example, but not exclusively) solid wastes such as precipitated solids, particles, . In one exemplary embodiment, the solid separation unit is a filter system that includes a nustch filter, a bag filter, and a press filter or any combination thereof, It is not. In another embodiment, the solid separation unit [F] is in fluid communication with the mixing unit [M] via stream 12. The extract, i. E. The alkylamine present as a solution if necessary, is introduced via stream 4 into the mixing unit. The alkyl amine and wastewater streams from streams 4 & 12, respectively, are mixed in the mixing unit [M]. In one embodiment, the mixing unit may be a stirred vessel reactor, a plug flow reactor, a static mixer, a jet mixer, a pump mixer, &Lt; / RTI &gt; or any combination thereof. The streams flow into the mixing unit [M], wherein the temperature in M ranges from about 10 [deg.] C to about 100 [deg.] C and the pressure is from about 1 to about 10 atm. In another embodiment, the weight ratio of PTA wastewater to alkyl amine solution ranges from about 100: 0.5 to about 20: 1. The time required for sufficient mixing / extraction varies from about 1 minute to about 120 minutes. In one embodiment, organic compounds such as terephthalic acid, p-toluic acid, 4-methylbenzoic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, isophthalic acid, orthophthalic acid, metal salts of such organic acids, But are not limited to); And other various organic compounds present in the PTA wastewater stream are extracted / withdrawn into the alkylamine solution. In one embodiment, the outlet of the mixing unit [M] enters directly into the settling unit [S], where the separation of the alkylamine solution from the aqueous wastewater stream is effected. In one embodiment, the settling unit [S] includes, but is not limited to, a gravity settling vessel and a centrifuge settler or a combination thereof. The mixing unit and the settling unit may be present in combination or individually in the system. The separated / treated aqueous wastewater (bottom layer) is collected separately via stream 6; Which is in fluid communication with the aerobic treatment assembly [ASP].

[0134] In one embodiment, the separated / treated aqueous wastewater stream 6 is treated by known aerobic / activated sludge processes to neutralize pH prior to being sent for further removal of COD caused by unextracted organic compounds do. The aqueous stream produced from the aerobic treatment assembly is discharged through stream 9. The sludge produced from the aerobic treatment assembly is discharged through stream 10.

[0135] In one embodiment, the upper alkylamine layer is separated via stream 7 and is referred to as recycled alkylamine, which is sent through stream 5 for further mixing with a new PTA waste water stream in the mixing unit; Alkylamine solutions are just as they can be recycled. The stream 7 connects the sedimentation unit [S] with the regeneration unit [ERU]. In one embodiment, the regeneration unit includes, but is not limited to, a distillation column, a filtration unit and an extraction column, or any combination thereof. In one embodiment, the regeneration unit is the extract regeneration unit. A small fraction of the alkylamine solution is regenerated by caustic solution (NaOH). The regenerated alkylamine solution stream 8 may be used for further extraction of contaminants / organic compounds from wastewater. The stream 8 connects the playback unit [ERU] with the stream 4, which in turn is connected to the mixing unit.

[0136] In one exemplary embodiment of the present disclosure, the process model for COD reduction in PTA wastewater by separation / recovery of contaminants / organic acids is depicted in FIG.

[0137] Further embodiments and features of the present disclosure will be apparent to those skilled in the art based on the description provided herein. The embodiments of the present invention provide various features and advantageous details thereof in the description. The description of well known / conventional methods and techniques has been omitted in order not to unnecessarily obscure the embodiments of the present invention. In addition, this specification provides embodiments that illustrate the above described implementations, and certain aspects have been utilized to illustrate the implementations herein. For the purposes of this disclosure, the embodiments utilized in the present invention are intended to be illustrative, and not restrictive, in order to facilitate understanding of the manner in which the embodiments of the present invention may be practiced and to enable others skilled in the art to practice the present invention It is only for the purpose of making it possible. Accordingly, the following examples should not be construed as limiting the scope of embodiments of the present invention.

Example

Example  One:

[0138] PTA wastewater The process is carried out by the present process for extracting or recovering organic compounds. Approximately 97.5 gm of PTA wastewater with an organic COD of about 8000-8400 ppm is mixed with 2.5 gm of a 1: 1 mixture of trioctylamine (TOA) and 1-octanol. The contents are mixed at about 50 DEG C for about 30 minutes. The contents of the flask are then transferred to a separatory funnel and the COD of the lower aqueous layer is measured to be in the range of 400 to 700 ppm. The upper organic phase is sent for regeneration.

Example  2:

[0139] The COD level of the wastewater from the PTA plant was determined by the potassium dichromate method to be about 8786 ppm. 97.5 gm of wastewater having a temperature of approximately 140 ° C is cooled to a temperature of approximately 50 ° C in the heat exchange unit [X]. The pH of the wastewater cooled from the heat exchange unit is adjusted to a pH of 2.5 in the pH adjustment unit. The wastewater is then mixed with about 2.5 gm of tri-octylamine in a mixing unit [M] at a temperature of about 50 ° C and atmospheric pressure: the duration is about 30 minutes. The weight ratio of amine to wastewater is about 2.5: 97.5. Contaminants in the wastewater stream are separated / extracted / recovered into the amine phase. The mixture from the mixing unit is injected into the settling unit [S], from which the separation of the amine and the upper layer comprising the recovered contaminant occurs from the lower layer comprising the treated wastewater. The COD level of the wastewater obtained separated and treated is about 500 ppm. The percentage of extraction is about 95%.

[0140] The separated aqueous wastewater is further injected into the biological treatment assembly [ASP] for further reduction of the COD level.

[0141] The separated amine upper layer is formed by entering the mixing unit and the precipitation unit Recycled, and then the amine is regenerated in the regeneration unit [IRU] to separate the residual contaminants from the amine. The regenerated amine is used for further extraction.

Example  3:

Example  3 (a): liquid-liquid extraction

[0142] First, the PTA wastewater solution is taken in a 1 L beaker (initial pH 4.4) and a few drops of 10% HCl solution are added to adjust the pH to 2.5. From this solution, approximately 97.5 gm of effluent is taken in a cedar round bottom flask. To this is added about 2.5 gm of TOA (trioctylamine). In a water bath at a temperature of about 50 DEG C for about 30 minutes , the contents of the flask are stirred using an overhead stirrer. Transfer the contents into a separate flask and allow the phase to separate for about 10-15 minutes. TOA forms an acid-amine complex with the organic acid present in the wastewater (Figures 4 (a) and 4 (b)). The organic phase comprising TOA with the organic acid / its salt floats inside the top phase. Raffinate (i.e., treated wastewater) is present in the lower aqueous phase and is completely separated by the gradient method: the COD value of this sample is measured. A separate 2.5 gm TOA (weight increased to about 2.6 gm) was further reused in another cycle according to the process, along with a fresh wastewater solution (pH adjusted) of about 97.5 gm. Similarly, an initial TOA of 2.5 gm is reused approximately three times. The results are shown in Table 2 below.

[00143] TOA is observed to reduce waste water COD from 8786 ppm to 522 ppm (i.e., 94% extraction). The regenerated TOA reduces waste water COD while providing an extraction of about 78-85%. Fig. 4 (g) shows a comparison of the samples of untreated wastewater and wastewater treated with alkylamine. As seen from Fig. 4 (g), the color of the untreated wastewater (extremely left) and the treated wastewater changes significantly. The color change of the treated wastewater is due to the removal of contaminants such as organic acids and their metal salts by alkylamine treatment.

Example  3 (b): TOA Playback of

[0144] After four recycling of the process, TOA is regenerated from the top organic phase using a caustic wash solution (10% NaOH). Approximately 2.5 - 2.9 gm TOA is washed / stirred to the required amount of about 10% NaOH solution until basic pH (8.0-8.5) is reached. After stirring for about 10 minutes, the contents of the mixture are separated using a separatory flask, where the top layer contains regenerated TOA (Figures 4 (c) and 4 (d)). This regenerated TOA is additionally used for liquid-liquid extraction of organic acids from fresh PTA wastewater.

[0145] During the extraction phase of the three-time recycle, TOA is converted to an acid-amine complex and the weight increases from 2.5 gm (TOA) to 2.85 gm (acid-amine complex). This increase of 0.35 gm results from the addition of acid to the TOA from the aqueous PTA wastewater to form an acid-amine complex.

[0146] During the regeneration step, the yield of TOA from the acid-amine complex is observed to be about 85%, the 2.85 gm weight of the organic acid-amine complex is reduced to about 2.13 gm and the initial TOA used in the extraction step is 2.5 g That's right.

Example  3 (c): Recovery of organic acid

[0147] The recovery of the organic acid from the reaction product enables a comprehensive economy of the overall reaction. The lower water-soluble layer obtained according to Example 3 (b) contains a metal salt of an organic acid such as sodium terephthalate, sodium acetate and the like. These metal salts are recovered by adding about 10% HCl solution to the aqueous layer until the mixture reaches an acidic pH of about 2-2.5 to ensure that each organic acid is formed with the regeneration of a metal salt such as NaCl (Figs. 4 (e) and 4 (f)). Where organic acids are slightly soluble in water (limited by temperature), and excesses beyond their solubility are precipitated. Solubilities of organic acid-terephthalic acid, benzoic acid and p-toluic acid are shown in Figures 5 (a) - (c). The formed metal salt, such as sodium chloride, is in soluble form (high solubility limit).

[0148] The organic acid is removed from the reaction mixture more preferably by water evaporation or water washing (the required amount) so that the salt present in the mixture (salt such as sodium chloride having a higher solubility as compared to the organic acid at a certain temperature) Purified.

[0149] The crystallization or precipitation of the obtained organic acid is carried out by cooling. Since the organic acids have less solubility in water, they crystallize first upon cooling. Filtration of crystallized organic acids from mother liquor results in the acquisition of high purity organic acids.

Example  4:

[0150] The wastewater from the PTA plant is applied to a single cycle of liquid-liquid extraction of the present disclosure in accordance with the protocol of Example 3 (a), using the alkylamines in the wastewater in the various ratios described in Table 3. Approximately 2.5 gm TOA is applied independently with approximately 97.5 gm, 195 gm, 292 gm, 390 gm and 585 gm wastewater. Table 3 shows the reduction of the COD level of wastewater. TOA reduces the initial COD of wastewater by 82-94% when used in proportions of about 1:39, 1:78, 1: 116.8 and 1: 156. However, when the ratio of alkylamine: wastewater is 1: 234, only about 57% COD reduction is observed.

Example  5:

[0151] FIG. The wastewater from the PTA plant is applied to a single cycle of liquid-liquid extraction of this disclosure in accordance with the protocol of Example 3 (a), using the alkyl amine in the wastewater at various pHs described in Table 4. The initial COD of the wastewater sample (designated F-1601) is 8798 ppm. At a pH of about 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, and 4.9, about 2.5 gm TOA is applied with about 97.5 gm of water. The COD levels of the wastewater treated at each pH condition and the final pH of the treated wastewater are shown in Table 4. TOA significantly reduces the initial COD of wastewater from about 8798 ppm to about 316-733 ppm at an initial pH of about 1.0 - 4.0. However, no decrease in COD was observed at an initial pH of 4.9.

[0152] In addition, HPLC analysis of various organic acids, i.e., isophthalic acid (IPA), benzoic acid (Bz-acid), orthophthalic acid (OPA), trimellitic acid (TMA) and p-toluic acid (PTA) (Tested at various pH values of about 1.0 to 4.5). The results obtained are shown in Figure 7, where it is observed that lowering the pH causes better extraction.

advantage

[0153] The disclosure of the present invention enables the extraction or recovery of organic compounds which are COD contributing factors in wastewater using amine extracts.

[0154] FIG. The disclosure of the present invention relates to a simple process for extracting organic compounds from wastewater.

[0155] The process of the present invention takes a shorter time compared to the long hydraulic residence time (residence time) associated with the anaerobic digestion process. In one embodiment, the process of the present disclosure employing liquid-liquid extraction requires a shorter residence time (about 10-50 minutes), where the residence time in the anaerobic digestion process is longer (about 24 hours).

[0156] The process of this disclosure can replace or eliminate the cost-intensive anaerobic digestion process typically used in PTA wastewater treatment processes.

[0157] In this process, the extractants (amines) are regenerated by a caustic wash on the organic phase containing the acid-amine complex.

[0158] In this process, the organic acid compounds that are COD contributing factors are recovered to an aqueous phase containing the sodium salt of terephthalate with HCl, resulting in a slight increase in the overall process yield.

[0159] The water produced after the treatment in the present process can be reused in the crude-terephthalic acid purification process after being treated with an essential tertiary treatment method such as, but not limited to, ultrafiltration, reverse osmosis and the like.

[0160] This disclosure can successfully overcome various deficiencies of the prior art and provide a process for the extraction or recovery of organic compounds.

[0161] Further embodiments and features of the present disclosure will be apparent to those of ordinary skill in the art based on the description provided herein. Embodiments of the present disclosure provide its various features and beneficial details in the description. The descriptions of well known / conventional methods and techniques are omitted so as not to unnecessarily dilute the embodiments of the present specification.

[0162] The foregoing description of specific embodiments is provided to enable any person skilled in the art to make and use the teachings of the present invention without departing from the generic concept, And that such adaptations and modifications are intended to be and are intended to be encompassed within the meaning and range of equivalents of the disclosed embodiments. The terms and terminology employed herein are for the purpose of description and not of limitation. Thus, implementations are described in terms of preferred implementations of the present disclosure, and those of ordinary skill in the art will understand that within the spirit and scope of the implementations described herein, As shown in FIG.

[0163] Throughout this specification, variations such as "including", "including", or "including", as used herein, exclude any other element, integer or step, or group, integer or step, But to be understood to imply the inclusion of a stated element, integer or step, or group of integers, or steps, or steps.

[0164] With regard to the use of substantially any plural and / or singular terms as used herein, one of ordinary skill in the art will recognize that a plurality may be singular and / or singular, as appropriate for the context and / It can be interpreted as plural. The various singular / plural substitutions may be expressly indicated herein for clarity.

[0165] The use of the phrase "at least" or "at least one" suggests the use of one or more elements or components or amounts, as may be used in embodiments of the disclosure to achieve one or more desired objects or results ,

[0166] Discussion of any document, activity, material, apparatus, literature, etc., is included herein for purposes of providing the context of this disclosure only. It exists as an arbitrary place prior to the priority date of the present application. It is not intended that any or all of these documents form part of the prior art basis or admit to the ordinary and general knowledge of the art relating to this disclosure.

[0167] It will be understood that, while a significant emphasis on certain features of the present disclosure is set forth herein, it will be appreciated that various changes may be made, without departing from the principles of this disclosure, and that many changes may be made in the preferred embodiments. These and other modifications within the spirit or the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, and the technical problems described above are not to be construed as limitations, It will be understood that it should be construed to explain the disclosure.

Reference number table

Claims (17)

a) adjusting the temperature of the wastewater and optionally the pH;
b) contacting the wastewater obtained in step a) with an alkylamine and mixing the resulting mixture;
c) culturing the mixture of step b) to obtain a lower layer comprising an upper layer comprising alkylamine and treated wastewater together with a contaminant; And
d) separating the top layer comprising alkylamine with contaminants from the bottom layer comprising treated wastewater;
&Lt; / RTI &gt; a) at least one heat exchange unit [X] arranged to receive wastewater, wherein at least one heat exchange unit is set to regulate the temperature of the wastewater;
b) at least one mixing unit [M] fluidly connected to at least one heat exchange unit [X], at least one mixing unit being set up to receive wastewater and an alkylamine from at least one heat exchange unit, Lt; / RTI &gt; And
c) at least one settling unit [S] fluidly connected to the mixing unit [M], wherein at least one settling unit receives from the at least one mixing unit a mixture comprising wastewater and an alkylamine, To obtain a bottom layer comprising the top layer and the treated wastewater, which comprises the top layer and the treated wastewater;
And a system for separating contaminants from the wastewater. The method according to claim 1,
The wastewater of step a) is adjusted to a temperature of from about 10 ° C to about 100 ° C and a pH of from about 1.0 to about 4.0;
Wherein the regulation of the temperature is carried out in a heat exchange unit [X];
Wherein the adjustment of the pH is carried out in a pH adjustment unit [pH];
Wherein the solid waste is separated from the wastewater of step a) in the solid separation unit [F], after the temperature and pH of the wastewater are adjusted. The method of claim 1, wherein the contacting and mixing are performed in a mixing unit [M]; The cultivation of step c) is carried out in a settling unit [S]; And wherein contacting, mixing, culturing or separating is carried out for a time period of from about 1 minute to about 120 minutes, in a pressure range of from about 1 atmosphere to about 10 atmospheres, and in a temperature range of from about 10 DEG C to about 100 DEG C Way. The method according to claim 1,
The top layer of step d) is separated from the bottom layer by decantation; Wherein the upper layer of step d) is treated to recover the alkylamine and contaminants separately; Wherein the treatment is carried out by a technique selected from the group comprising solvent extraction, caustic neutralization, filtration, distillation and combinations thereof;
The treatment is carried out in a unit selected from the group comprising a settling unit [S] and a regeneration unit [ERU] and combinations thereof; And
Wherein the lower layer of step d) is further treated in at least one biological treatment assembly [ASP] to obtain aqueous wastewater. 3. The method of claim 2,
The system comprises at least one pH adjusting unit [pH] arranged to receive wastewater set between at least one heat exchange unit [X] and at least one mixing unit [M]
Wherein at least one pH adjusting unit [pH] is set to adjust the pH of the wastewater. 7. The method according to claim 2 or 6,
The system comprises at least one solid separation unit [F] set between at least one heat exchange unit [X] or at least one pH adjustment unit [pH] and at least one mixing unit [M] ,
Wherein the at least one solid separation unit is configured to separate solid waste from the wastewater. The apparatus according to claim 2, wherein at least one regeneration unit [ERU] is fluidically connected to at least one settling unit,
Wherein at least one regeneration unit is arranged to receive from the at least one settling unit an overlying layer comprising alkylamine with contaminants and configured to separate the alkylamine and the contaminant. 3. The system of claim 2 wherein at least one settling unit is fluidly connected to at least one biological treatment assembly [ASP] to obtain wastewater from the settling unit. 3. The system of claim 2 wherein at least one mixing unit comprises an inlet port fluidly connected to an alkylamine source through a first passageway. 11. The system according to claim 2, 8 or 10, wherein the system comprises at least one of at least one regeneration unit [ERU] and at least one settling unit [S]; And a bypass passage fluidly connected between the first passageways. The method according to any one of claims 3 to 5, or in any one of claims 2 and 6 to 9,
The system operating in a mode selected from the group comprising a batch mode, a semi-continuous mode, a continuous mode, and combinations thereof;
The heat exchange unit [X] is a heat exchanger selected from the group comprising a shell heat exchanger, a tube heat exchanger, a flash evaporator, and combinations thereof;
The solid separation unit [F] is selected from the group comprising a nustch filter, a bag filter, a press filter, and combinations thereof;
The mixing unit [M] is selected from the group comprising a stirred vessel reactor, a plug flow reactor, a static mixer, a jet mixer, a pump mixer and combinations thereof;
The settling unit [S] is selected from the group comprising gravity settling vessels and centrifuge settlers and combinations thereof;
The biological treatment assembly [ASP] is an activated sludge assembly; And
Wherein the regeneration unit [ERU] is selected from the group comprising distillation columns, filtration units, extraction columns and combinations thereof. 3. The method according to claim 1 or 2,
The wastewater comprises contaminants selected from the group consisting of aliphatic hydrocarbons or aromatic hydrocarbons, derivatives thereof, and combinations thereof; And
Wherein the hydrocarbon compound or derivative thereof is selected from the group comprising organic acids, metal salts of organic acids and combinations thereof;
Wherein the organic acid is selected from the group comprising benzoic acid, p-toluic acid, terephthalic acid, 4-carboxybenzoic acid, trimellitic acid, acetic acid, 4-methylbenzoic acid, isophthalic acid, orthophthalic acid,
Wherein the cation in the metal salt of the organic acid is selected from the group comprising sodium, magnesium, potassium and combinations thereof, and the anion in the metal salt of the organic acid is selected from the group consisting of terephthalate, acetate, benzoate, isophthalate, trimethylate, methylbenzoate, , Carboxybenzoate, and combinations thereof. 3. The method according to claim 1 or 2,
The wastewater is selected from the group comprising industrial wastewater, purified terephthalic acid (PTA) wastewater, petrochemical wastewater, pharmaceutical industry wastewater, isophthalic acid wastewater, and combinations thereof;
Wherein the alkyl amine is a secondary amine, tertiary amine, and will be selected from a combination thereof, wherein the secondary alkyl amine is C ₆ -C alkyl having a chain length of any of the ₁₀ amines, and; And wherein the tertiary alkyl amine is an alkyl amine having an arbitrary chain length of C ₆ -C _10; Or a combination thereof. 3. The method according to claim 1 or 2,
Wherein the alkylamine is selected from the group comprising trihexylamine, trioctylamine, and combinations thereof. 3. The method according to claim 1 or 2,
The alkylamine is present in solution,
Wherein the solution is a diluent of a long chain hydrocarbon, preferably selected from the group comprising chlorinated hydrocarbons, ketones, alcohols, halogenated aromatic solvents and combinations thereof; And
Wherein the weight ratio of alkyl amine to wastewater is in the range of from about 0.5: 100 to about 1:20, preferably from about 0.5: 100 to about 3: 100. The method according to claim 3 or 7,
Wherein the solid waste is selected from the group consisting of precipitated organic acids, solid particulate materials, and combinations thereof.

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