JPH0378157B2 - - Google Patents

Description

[Detailed description of the invention]

<Field of Industrial Application> The present invention relates to a water purification material capable of purifying organic wastewater containing phosphorus compounds, nitrogen compounds, and organic substances such as livestock urine wastewater, miscellaneous wastewater, and sewage, and an organic wastewater treatment using the same. To be more specific, we devised a method to easily and efficiently remove SS (suspended solids) and BOD (biochemical oxygen demand), as well as dephosphorization and denitrification using a simple process. It is something. <Prior art and its problems> Organic wastewater such as livestock urine wastewater, miscellaneous wastewater, and sewage causes eutrophication that induces "blue water" and "red tide" in lakes and inland seas. Conventionally, there are various methods for treating organic sewage, such as activated sludge method, sprinkled bed method, and rotating disk contact method, but there are
The immersed bed method is often adopted for many reasons, including maintenance. In this immersed bed method, an aerobic bed tank is filled with a contact material, and sewage is poured into it and aerated to form a biofilm on the surface of the contact material, and the sewage is purified by the action of microorganisms in this biofilm. It is something. In addition, gravel, plastic pieces, honeycomb tubes, etc. are used as contact materials for this immersed bed method. However, although the above-mentioned immersed bed method can remove organic matter, it cannot sufficiently remove nitrogen compounds and phosphorus compounds such as phosphoric acid and phosphates (hereinafter referred to as phosphorus), so the treated water is not allowed to flow into a closed water system. When released, it causes eutrophication and causes great damage to fisheries and other industries. Therefore, when organic wastewater is treated by the soaked bed method, it is necessary to separately perform denitrification and dephosphorization. Therefore, biological denitrification methods are generally used along with the soaked bed method. In this biological denitrification method, an anaerobic bed tank is installed after the aerobic bed tank in the immersed bed method, and NH ⁺ ₄ -N is oxidized by nitrite bacteria and nitrate bacteria in the aerobic bed tank. changed
NO ^- ₂ -N and NO ^- ₃ -N are reduced to N ₂ gas by denitrifying bacteria in an anaerobic bed tank under anoxic conditions. However, in order to fully perform this denitrification, it is necessary to use an aerobic bed tank in the immersed bed method.
Oxidation of NH ⁺ ₄ -N to NO ^- ₂ -N and NO ^- ₃ -N, that is, nitrification, must be carried out sufficiently, but as the nitrification progresses, the pH decreases, so the alkali Neutralization treatment with a chemical agent is required, which poses a problem of complicating management and equipment, and also imposes a large economic burden due to the use of chemicals. Conventionally, such denitrification is followed by dephosphorization. There are two methods of dephosphorization: one is to precipitate and remove it as a phosphate by reaction with a metal salt such as calcium salt, aluminum, or iron, and the other is to crystallize and dephosphorize it as hydroxyapatite in an alkaline region in the presence of calcium. However, either method requires separate equipment called a dephosphorization device or a dephosphorization tank. In addition, the former sedimentation removal method generates a lot of sludge and is difficult to dewater, making treatment difficult, and the use of chemicals imposes a large economic burden. Although the amount of sludge generated and the amount of chemicals used are small, calcium concentration adjustment and pH
There is a problem in that it is difficult to control the pretreatment process that creates conditions for crystallization, such as adjustment and decarboxylation, and the management and equipment become complicated. In any case, when treating organic wastewater,
Currently, three steps are essential: organic matter removal (soaked bed method), denitrification, and dephosphorization. Here, an example of a process for treating such organic wastewater will be explained with reference to FIG. As shown in the figure, organic sewage is primarily treated in a screen settling tank 1 and a vibrating sieve 2 to remove floating matter and sediment, and then diluted with water in a dilution tank 3, which is then suitable for the soaked bed method. In addition to removing organic matter in the air tank 4, sufficient nitrification is performed while adjusting the pH using an alkaline agent. Next, methanol is added and stirred in the stirring tank 5, followed by denitrification in the anaerobic tank 6, organic matter removal again in the re-aerobic tank 7, and sent to the dephosphorization step. The dephosphorization process includes decarboxylation by adding sulfuric acid in the decarboxylation tank 8, pH adjustment by adding gypsum and slaked lime in the PH adjustment layer 9, and
The pretreatment process consists of precipitating CaCO ₃ etc. in the precipitation tank 10, and crystallization dephosphorization in which phosphorus is removed as hydroxyapatite in the dephosphorization tank 11. The treated water after this dephosphorization process is sent to the disinfection tank. After being disinfected at step 12, it is drained. As described above, in the past, when treating organic wastewater, a large number of facilities and sophisticated operational management were required. In view of these circumstances, the present invention has been developed to remove organic matter,
It is an object of the present invention to provide a water purification material that can easily and efficiently perform denitrification and dephosphorization in a simple process, and a method for treating organic wastewater using the same. <Means for Solving the Problems> As a result of various studies to achieve the above-mentioned object, the present inventors have discovered that a certain type of composition consisting of calcium silicate hydrate can be used in the biofilm method for organic raw wastewater. The present invention was completed based on the findings that the treatment with nitrification creates a favorable environment for microorganisms to live in, crystallizes out phosphate ions, and maintains a pH suitable for nitrification. The water purification material according to the present invention is obtained by hydrothermal reaction treatment of a foamed cured product obtained by foaming and curing a water slurry consisting of a siliceous raw material and a calcareous raw material in the presence of a foaming agent, and The organic wastewater treatment according to the present invention is characterized in that microorganisms are allowed to live on the surface of a porous contact material mainly composed of porous calcium silicate hydrate having a vacancy of 90%. The method is
In a method for treating organic wastewater containing phosphorus compounds, nitrogen compounds, and organic substances, the organic wastewater and/or anaerobically treated water is passed through an aerobic region containing a porous contact material to the porous contact material in the presence of air. contacting the water to produce aerobic treated water; and contacting the aerobic treated water with a hydrogen donor in substantially the absence of air to produce anaerobic treated water, the porous contact material comprising: , obtained by hydrothermal reaction treatment of a foamed cured product obtained by foaming and curing an aqueous slurry consisting of a siliceous raw material and a calcareous raw material in the presence of a foaming agent, and having a porosity of 50 to 90%. It is characterized by having porous calcium silicate hydrate as its main component. The configuration of the present invention will be explained in detail below. The water purification material according to the present invention is one in which microorganisms are made to live on the surface of a specific porous contact material, but it may be one that has been previously treated to make microorganisms live there,
It is also possible to treat organic sewage so that microorganisms can live there at an early stage. The porous contact material that is the base material of the water purification material according to the present invention will be specifically explained. This porous contact material is, for example, a calcium silicate water obtained by adding a foaming agent such as aluminum powder to a water slurry whose main raw materials are silicic raw materials and calcareous raw materials, and performing a hydrothermal reaction treatment under high temperature and high pressure. A molded product made of a compound or a crushed product obtained by crushing this molded product.
50% to 90%, or by pulverizing a water slurry whose main raw materials are silicic raw materials and calcareous raw materials after hydrothermal reaction treatment under high temperature and high pressure. Granules or molded products made of molded calcium silicate hydrate with a void ratio of 50 to 90.
%belongs to. Here, calcium silicate hydrate is prepared by combining a silicate raw material and a calcareous raw material at a predetermined CaO/SiO ₂ molar ratio (0.5~
2.0) and is obtained by curing at high temperature and high pressure under the required pressure and temperature in an autoclave according to a conventional method. Silica raw materials include silica stone, silica sand, cristobalite, amorphous silica, diatomaceous earth, Powder such as ferrosilicon dust, white clay,
Examples of calcareous raw materials include powders such as quicklime, slaked lime, and cement. The calcium silicate hydrate thus obtained is one or more selected from the group consisting of tobermorite, xonotlite, CSH gel, phosiyaite, gyalolite, heleprandite, and the like. Also, among these, tobermorite, xonotlite, and CSH gel have high PH buffering ability and a specific surface area of 20 to 400 m ² /g.
It is especially preferable because it is large. The porous contact material used in the present invention has a porosity of 50 to 90%, but when this porosity is obtained during the production of calcium silicate hydrate, the silicic material and calcareous material are made into a slurry. After adding a foaming agent such as a metal foaming agent such as aluminum powder or a foaming agent such as an AE agent to the material, the foaming agent may be subjected to a hydrothermal reaction treatment at high temperature and high pressure. Here, the metal foaming agent generates gas through a chemical reaction, and its usage ratio varies depending on the amount of air bubbles and water entrained in the slurry, but can be derived from the chemical reaction equation. Specific examples of foaming agents include resin soaps, saponins, synthetic surfactants, hydrolyzed proteins, and polymeric surfactants, which mainly introduce air bubbles physically through surfactant action. There are cases where foam is generated simply by mixing with the raw material and stirring, and cases where stable foam is created using a special stirring tank or foaming device, and this foam is measured by volume and mixed with the raw material. be. When using such a foaming agent, it is necessary to test the stability of the foam and then determine the amount to be added. In addition, if you obtain calcium silicate hydrate with a small porosity, if it is a molded product, you can adjust the porosity by adding air bubbles during the granulation or molding process after pulverizing it. . In other words, an aqueous solution of a sizing agent of a polymer resin such as an acrylic resin emulsion is added to powdered calcium silicate hydrate, a foaming agent is added if necessary, the mixture is kneaded, and the mixture is granulated using a pan pelletizer or molded. All you have to do is form a frame. As the drying method here, either natural drying or heat drying may be employed. Also, here,
As the powdered calcium silicate hydrate, a powder obtained by crushing a molded product containing voids as described above may be used. In addition, when forming a porous contact material with a high porosity, it is preferable to employ mold molding. The method for treating organic sewage according to the present invention is to pass organic sewage, which has undergone primary treatment to remove floating matter and sediment, through an aerobic bed tank filled with such a porous contact material without diluting it while aerating it. By doing so, organic matter is removed using the biofilm method. That is, as a result, microorganisms live on the surface of the porous contact material and become a water purification material, and the water purification material removes organic matter by the biofilm method. In the same way, phosphorus removal and nitrification of NH ⁺ ₄ −N are performed simultaneously, and NO ⁻ ₂ − in which NH ⁺ ₄ −N is nitrified is also removed.
Treated water containing N, NO ^- ₃ -N is introduced into an anaerobic bed tank, a hydrogen donor such as methanol is added, and NO ^- ₂ -N, NO ^- ₃ - is produced by denitrifying bacteria in an aerated anaerobic state.
Biological denitrification can be performed by reducing N to _N2 gas. Here, the porous contact material that is the base of the water purification material filled in the aerobic bed tank has microscopic irregularities on the surface of calcium silicate hydrate crystals or gel, so microorganisms can It is easy to fix and form a biofilm, and it also alleviates the pH drop caused by lower fatty acids such as lactic acid, butyric acid, and acetic acid, which are decomposition products of organic matter (microbial metabolites), and is the optimal pH for microorganisms. Alkaline pH8~
9 can be stably created. Therefore, in the aerobic bed tank of the method of the present invention, the activities of bacteria and protozoa that contribute to the decomposition of organic matter as well as nitrite bacteria and nitrate bacteria that perform nitrification become active, making it possible to process at high loads. Even if the organic sewage to be introduced has a high concentration similar to urine sewage from a general pig farm, dilution is not required. Moreover, the dephosphorization that is simultaneously carried out in such an aerobic bed tank is due to the following action. The porous contact material, which is the base of the water purification material in the aerobic bed tank, supplies the Ca ²⁺ necessary for crystallization of calcium hydroxyapatite from the crystal or gel surface of the calcium silicate hydrate that forms it. At the same time, the PH buffering ability of the contact material reduces the PH of the wastewater.
PH is low, and even if the value fluctuates, the pH is always around 8 to 9.
As a result, phosphate ions in the wastewater react with Ca ²⁺ and crystallize on the surface of the contact material in the form of calcium hydroxyapatite. At this time, the voids in the porous contact material act to disturb the flow of wastewater in one direction and to moderate the flow velocity on the surface of the contact material, so calcium hydroxyapatite formed by phosphate ions and Ca ²⁺ The precipitation or growth of is promoted. Also,
This porous contact material does not contain "crystal seeds" similar to calcium phosphate or calcium hydroxyapatite, but it has adsorption ability, so it adsorbs the generated calcium hydroxyapatite at the initial stage of water flow, and thereafter The surface has a structure suitable for the formation of calcium hydroxyapatite nuclei, and calcium hydroxyapatite nuclei are formed in the microscopic cavities and pores. When the porous contact material after sewage treatment, that is, the water purification material of the present invention, is observed with a scanning electron microscope, a large amount of microorganisms settles inside the pores and on the crystal surfaces.
Amorphous crystals were also observed, which were identified as calcium hydroxyapatite by EPMA (X-ray microanalyzer). As is clear from this, the pores and cavities of the porous contact material, which is the base of the water purification material, have a great effect on the attachment of microorganisms and dephosphorization, and the porous contact material used in the present invention A vacancy rate of 50 to 90%, preferably 60 to 80% is desirable for microbial implantation and dephosphorization. If the vacancy rate of this porous contact material is less than 50%, the specific surface area is small, making it difficult for microorganisms to settle and the phosphorus removal rate is low. On the other hand, if the vacancy rate exceeds 90%, sewage is introduced into the aerobic bed tank. As a result of aeration, surfacing occurs and the strength decreases significantly, and PH
The durability of the buffering capacity and phosphorus removal effect also deteriorates.
Undesirable. Further, the size of the porous contact material used in the present invention also has a large effect on the phosphorus removal performance. If the diameter of the contact material is smaller than 0.5 mm, it will be easily clogged by SS and crystallization, so it cannot be used for a long period of time.On the other hand, if the diameter is too large, the phosphorus removal rate will decrease due to the reduction of the contact area. Both are undesirable. Therefore, it is desirable that the porous contact material has a size of 0.5 to 10 mm. Here, an example of the method for treating organic wastewater according to the present invention is shown in FIGS. 1 and 2. The example shown in FIG. 1 is an example in which an anaerobic bed tank is placed next to an aerobic bed tank. As shown in the figure, organic sewage that has been primarily treated in a screen settling basin 1 and a vibrating sieve 2 is introduced into an aerobic tank (aerobic bed tank) 3 filled with the above-mentioned porous contact material to remove organic matter. , dephosphorization and nitrification are performed. Next, the water is introduced into a stirring tank 4 and methanol or organic wastewater is added thereto, denitrified in an anaerobic tank (anaerobic bed tank) 5, and drained through a re-aerobic tank 6 and a disinfection tank 7. FIG. 2 is an example of a circulating treatment process. As shown in the figure, organic sewage that has been primarily treated in a screen settling tank 1 and a vibrating sieve 2 passes through an agitation tank 13 and an anaerobic tank 14, and then is introduced into an aerobic tank 15 filled with a porous contact material. , and further circulated to the stirring tank 13. This performs organic matter treatment, dephosphorization, and denitrification. This treated water is drained through a re-anaerobic tank 16 and a disinfection tank 7. As is clear from this, according to the organic wastewater treatment method according to the present invention, the number of steps is significantly reduced compared to the conventional method, and operation management is also facilitated. Furthermore, the porous contact material used in the present invention also has the function of adsorbing heavy metals, so if heavy metals are contained in organic wastewater, they will be removed together with organic matter and phosphorus. Incidentally, the used water purification material obtained by the method of the present invention can be reused as a silicate lime fertilizer and a soil improvement material, which is very economical. Below, examples of manufacturing a porous contact material that is the base material of the water purification material of the present invention and test examples showing the effects of the present invention are shown. (Manufacturing example of porous contact material) (1) CSH gel contact material 4 parts by weight of silica powder, 2 parts by weight of quicklime powder, 1 part by weight of slaked lime powder, and 3 parts by weight of ordinary Portland cement (CaO/SiO ₂ molar ratio = 1.5) 0.008 parts by weight of metallic aluminum powder was added to the mixture, and 7 parts by weight of water was added to make a water slurry.
Next, this water slurry was poured into a mold, left to stand for 4 hours, and then removed from the mold, which was then crushed with a rotating brush.
After granulation with a pan pelletizer to a particle size of 5 to 10 mm, the mixture was hydrothermally treated in an autoclave at 150°C under 5 atm for 10 hours to obtain a porous contact material. The void ratio of this contact material was 70%. (2) Tobermorite contact material 5 parts by weight of silica powder, 2 parts by weight of quicklime powder, and 3 parts by weight of ordinary Portland cement (CaO/
_SiO2 molar ratio = 0.8) to metallic aluminum powder
7 parts by weight of water was added to the mixture formed by adding 0.008 parts by weight to form a water slurry. This water slurry was poured into a mold, left to stand for 4 hours, and then removed from the mold, which was then hydrothermally treated in an autoclave at 180° C. and under 10 atmospheric pressure for 10 hours. The obtained molded product was crushed using a crusher and sieved to a particle size of 5 to 10 mm to obtain a porous contact material. The empty rate for this item was 75%. (3) Zonotlite contact material Silica stone powder and quicklime powder are mixed so that the CaO/SiO ₂ molar ratio is 1.0, and
It was dispersed in 10 times its weight of water to form a water slurry, and then hydrothermally treated in an autoclave at 210°C under 20 atm with stirring for 10 hours. Acrylic resin emulsion (solid matter 10%
%) was added 4 times by weight, kneaded, and then granulated to form 110
The mixture was dried and solidified at ℃ and sieved to particles with a particle size of 5 to 10 mm to obtain a porous contact material. The empty rate of this thing is
It was 73%. (4) Tobermorite contact materials with various porosity In the production method shown in (2) above, various tobermorite contact materials were obtained by changing the addition ratio of metal aluminum powder and water as shown in Table 1. .

[Table] Test example 1 As shown in Figure 3, a porous contact material was filled.
First tank 101 of 200×150×310mm and 200×150
The primary treated water of swine urine sewage, which has been subjected to solid-liquid separation and passed through a 0.3 mmφ steel vibrating sieve, is passed through the second tank 102 of ×290 mm in an upward flow. By performing aeration from below at a rate of 500 ml/min, the performance of water purification materials using various porous contact materials as base materials was investigated. Here, the above production example (1),
The porous contact materials manufactured in (2) and (3) are filled into the first and second tanks 101 and 102 to supply the primary treated water.
Test examples A-1, A-2, and A-3 were obtained by passing water at a flow rate of 10/day. For comparison, instead of the porous contact material, commercially available ballast, pumice, limestone, and polypropylene were used with particle sizes of 5 to 5.
Comparative Examples B-1, B-2, B-3, and B-4 were made using a 10 mm contact material as a contact material. These Test Examples A-1 to A-3 and Comparative Example B-
1 to B-4 after 2 to 3 months, the clarity, PH, BOD and T-P (total phosphorus) of the treated water,
Each concentration of NH ⁺ ₄ −N, NO ⁻ ₂ −N, and NO ⁻ ₃ −N was
The measurements were taken twice and the averages are shown in Table 2.

[Table] As shown in this result, BOD volume load 1.0Kg/
In high-load processing of ³ days/m3, the BOD removal rate in the comparative example was 77-87%, while in the method of the present invention it was 95%.
This showed a high removal rate. Further, the removal rate of phosphorus was 25% or less in the comparative example, which was hardly removed, but the method of the present invention had a high removal rate of 90% or more. Furthermore, in order to perform denitrification in the next step, it is necessary to nitrify organic nitrogen and NH ⁺ ₄ -N to NO ^- ₃ -N or NO ^- ₂ -N, but according to the method of the present invention, NH ⁺ ₄ -N volumetric load is 0.4Kg/day・m ³
Even with the high-load treatment, nitrification has progressed completely, making it possible for complete denitrification to occur in the next process.
On the other hand, in the comparative example, 10 to 30% of NH ⁺ ₄ -N remains, so even if a biological denitrification process is added afterwards, this remaining NH ⁺ ₄ -N will be washed away as is. Become. Test Example 2 The same experimental equipment as in Test Example 1 was used, and the various porous contact materials shown in Production Example (4) were used to treat primary treated pig urine water. The difference in purification was tested. Note that other conditions were the same as in Test Example 1. Similar to Test Example 1, the results are shown in Table 3, which is the average of four measurements over a period of 2 to 3 months.

【table】

[Table] As shown in Table 3, the porosity of the porous contact material is
When it is 50% or more, the effect of BOD removal and phosphorus removal is large and nitrification progresses sufficiently. In addition, the vacancy rate is 90%
If it exceeds this value, it will flow out of the tank due to the floating phenomenon when water is passed through, and at the same time, the strength will decrease significantly. These results show that the void structure of the porous contact material is extremely important for increasing the contact opportunities between the purifying material and organic wastewater and for allowing microorganisms to settle within the pores and voids. It is also extremely important for the crystal growth of calcium hydroxyapatite that crystallizes at the same time, and greatly contributes to the phosphorus removal effect. <Example> Example 1 In this example, A to F as shown in FIG.
A concrete sewage treatment system consisting of six treatment chambers was used. Here, A, B and F are aerobic bed tanks, and A and B are made of porous contact material mainly composed of tobermorite with a particle size of 5 to 15 mm, manufactured in the same manner as in Production Example (2) above. However, F is filled with a similar tobermorite contact material having a particle size of 5 to 8 mm, and aeration pipes 110a to 110c are provided below each of them for aeration. These diffuser cylinders 110a to 110c are connected to an air pump 113 via an air pipe 111 and an air adjustment valve 112. The processing tank C is a stirring tank, and methanol is supplied from the methanol tank 114. Furthermore, D and E are anaerobic bed tanks filled with commercially available anthracite having a particle size of 5 to 10 mm. In such a sewage treatment apparatus, the primary treated water of pigsty sewage was treated by passing through the sewage inlet pipe 115 at a flow rate of 600/day, and the treated liquid was discharged from the discharge pipe 116. Note that the methanol addition flow rate in the processing chamber C is 1.2/day. The treatment was carried out under these conditions for about 6 months, and the PH, transparency, and
BOD, SS, TP and TN (total nitrogen) were each measured. The results are shown in FIG. As is clear from the figure, according to this example, organic matter, phosphorus, and nitrogen in the pigsty wastewater are reliably removed over a long period of time. Example 2 In this example, a concrete sewage treatment apparatus consisting of six treatment chambers G to L as shown in FIG. 6 was used. Here, I and J are aerobic bed tanks, and these tanks are filled with a contact material whose main structure is tobermorite with a particle size of 5 to 10 mm, which was produced in the same manner as in Production Example (2) above. Below that are aeration cylinders 120a and 120b for aeration.
is installed. These aeration cylinders 120a, 12
0b is connected to an air pump 123 via an air pipe 121 and a regulating valve 122. On the other hand, treatment tanks G and H are anaerobic bed tanks filled with commercially available anthracite with a particle size of 5 to 15 mm, and wastewater is introduced from a wastewater introduction pipe 125 and methanol is supplied from a methanol tank 124. It is becoming more and more like this. The wastewater that has passed through G and H is treated in aerobic tanks I and J, and then from a treatment tank K to a circulating water introduction pipe 127 and a flow pump 128.
It is designed to be circulated to the G processing tank via the . Furthermore, a re-anaerobic tank L is provided after K, and this tank is filled with anthracite similar to G and H. In such a sewage treatment device, primary treated water from the pigsty sewage is passed through the sewage inlet pipe 125 at a flow rate of 600 g/day, and the water is circulated from K to G.
5400/day, and since the nitrogen concentration in the wastewater was high and the BOD source in the wastewater alone was insufficient for the denitrification effect, methanol as a hydrogen donor was supplied to the anaerobic tank G at 0.2/day. In this way,
The wastewater was treated for about 6 months, and the PH, transparency, BOD, SS, TP, and TN of the primary treated water and the treated liquid discharged from the treated discharge pipe 126 were measured. The results are shown in FIG. As is clear from the figure, according to this example, organic matter, phosphorus, and nitrogen in the pigsty wastewater are reliably removed over a long period of time. Here, the results of Examples 1 and 2 will be considered in more detail. As shown in FIGS. 5 and 7, Examples 1 and 2
In this case, purification has progressed from about 4 weeks after the sewage was introduced, and the quality of the treated water has been stable since the 8th week. Here, when the measurement results of the water quality of the treated water after the 8th week of Examples 1 and 2 are averaged, the results are as shown in Table 4.

[Table] As shown in Table 4, both Examples 1 and 2,
It shows a high removal rate not only for BOD and SS, but also for TP and TN, which is an extremely high level of processing result. Regarding heavy metals, 20% in Example 1
The inflow sewage and discharged treated water were measured for the first week, and the results are shown in Table 5.

[Table] As shown in the table, copper contained in pig farm wastewater,
More than 90% of the heavy metals in zinc were removed by the treatment of this example. <Effects of the Invention> As specifically explained above with the test examples and examples, according to the present invention, organic matter, nitrogen and phosphorus can be efficiently removed through simple and easy treatment without the need for complicated steps. It is easy to remove, maintain and manage, and can also treat high-concentration wastewater such as livestock urine sewage and industrial wastewater with a high load, making it possible to downsize and simplify the processing equipment. Further, according to the present invention, copper, zinc,
Heavy metals such as lead can also be removed at the same time. Furthermore, water purification materials whose treatment capacity has decreased due to long-term use can be reused as silicate lime fertilizers and soil improvement materials, which is economical.

[Brief explanation of drawings]

1 to 7 are related to the present invention, FIGS. 1 and 2 are process diagrams showing an example of a method for treating organic wastewater, and FIG. 3 is an explanatory diagram showing an apparatus used in a test example.
Fig. 4 is an explanatory diagram showing the sewage treatment equipment used in the first example, Fig. 5 is an explanatory diagram showing the results of the first example, and Fig. 6 is an explanatory diagram showing the sewage treatment equipment used in the second example. FIG. 7 is an explanatory diagram showing the results of the second example, and FIG. 8 is a process diagram showing the organic wastewater treatment process according to the prior art. In the drawing, 3 and 15 are aerobic bed tanks, and 5 and 14 are anaerobic bed tanks.

Claims (1)

[Scope of Claims] 1. A foamed cured product obtained by foaming and curing an aqueous slurry consisting of a silicic raw material and a calcareous raw material in the presence of a foaming agent, and
A water purification material characterized by having microorganisms living on the surface of a porous contact material mainly composed of porous calcium silicate hydrate having a vacancy rate of 50 to 90%. 2. The water purification material according to claim 1, wherein the porous calcium silicate hydrate is one or more selected from the group consisting of tobermorite, xonotlite, CSH gel, phosiyaite, gyalolite, and hireplandite. 3. In a method for treating organic wastewater containing phosphorus compounds, nitrogen compounds, and organic substances, passing the organic wastewater and/or anaerobically treated water into an aerobic region containing the porous contact material in the presence of air. and a step of contacting the aerobically treated water with a hydrogen donor in substantially the absence of air to obtain anaerobic treated water, the porous contact material However, a foamed cured product obtained by foaming and curing an aqueous slurry consisting of a siliceous raw material and a calcareous raw material in the presence of a foaming agent and having a porosity of 50 to 90% is obtained by hydrothermal reaction treatment. 1. A method for treating organic wastewater, characterized in that the main component is porous calcium silicate hydrate. 4. The method for treating wastewater according to claim 3, wherein the porous calcium silicate hydrate is one or more selected from the group of tobermorite, xonotlite, CSH gel, phosiyaite, gyalolite, and hireplandite.