KR102056184B1 - Apparatus for crystallization wastewater and method for crystallization wastewater - Google Patents

Abstract

Provided are a crystallization apparatus for water to be treated and a crystallization method therefor. The crystallization apparatus facilitates a crystallization reaction for ions to be removed or contaminants present in the water to be treated, and improves the efficiency of the crystallization reaction without the crystallized particles easily flowing out of a reactor, thereby greatly reducing the operating cost of the crystallization apparatus.

Description

Crystallization Apparatus and Crystallization Method of Treated Water {Apparatus for crystallization wastewater and method for crystallization wastewater}

The present invention relates to a crystallization apparatus and a crystallization method of the water to be treated, more specifically, the crystallization reaction to the pollutants or ions to be removed in the water to be treated is easy, and the resulting crystallized particles are easily The present invention relates to a crystallization apparatus and a crystallization method of water to be treated, which significantly reduce the running cost of a crystallization apparatus by improving the efficiency of the crystallization reaction without flowing out.

The contents described in this section merely provide background information on the present embodiment and do not constitute a prior art.

Crystallization of contaminants or ions present in treated water (raw water), such as liquid materials or wastewater, occurs by injection of chemicals (hereinafter referred to as crystallization agents) necessary for proper pH and crystal formation. When the reactants (called seeds) are filled to form crystals in the granular reactor and the treated water is introduced from the lower part to the upper part, the packing material flows in the reactor by buoyancy. This reactor structure is called a fluidized bed reactor (FBR) and is known as a suitable reactor for crystallization.

In one example, the FBR has a harvesting section at the bottom to prevent the fine particles from moving upward and outward, and consists of a column comprising one or two continuous sections thereon, the top continuous The section has a larger cross-sectional area than the lower section and is generally installed in a vertical direction to prevent the microparticles from moving upward and outflow. However, the seed can grow into large crystals inside the reactor because it cannot effectively prevent the outflow of the microparticles. Does not exist sufficiently and contains fine particles in the effluent treated water, there is a disadvantage that a separate sedimentation facility for removing them is required.

In order to effectively react in the crystallization reaction, there is a need for an apparatus capable of continuously generating fine particles and inducing such microparticles to react with the treated water and surrounding fine particles in the apparatus without external leakage.

US Patent No. 7622047

The inventors of the present invention fabricate the device so that the fluid flow is a laminar flow, so that the fluid is slow in moving, so that sufficient agitation does not occur and crystals are not generated. In this case, the flow rate of the fluid is high, and the microparticles do not stay and are discharged together with the effluent. Thus, the crystallization apparatus has been designed and the present invention has been completed.

That is, the present invention is designed to have a different fluid flow for each of the crystallization reaction zone, solid-liquid separation reaction zone, and precipitation reaction zone, so that the crystallization reaction is easy, and the fine particles produced by the crystallization reaction outflow It is an object of the present invention to provide a crystallization apparatus and a crystallization method of water to be treated to be effectively maintained inside the apparatus to grow into microcrystals.

Still other objects not specified in the present invention may be further considered within the scope that can be easily inferred from the following detailed description and effects thereof.

In order to solve the above problems, the crystallization apparatus according to an embodiment of the present invention,

A reaction tank in which a seed is filled inside, and the water to be treated containing contaminants or ions and a crystallization agent are reacted in a turbulent phase and crystallized on the surface of the seed, and the reactant which is not crystallized on the seed is produced as microparticles;

A separation tank provided on the reaction tank and having laminar flow and turbulent flow coexisting to return some of the fine particles rising by buoyancy to the reaction tank; And

And a sedimentation tank provided on the separation tank and generating laminar flow so that some of the microparticles rising by buoyancy do not flow out to precipitate the microparticles.

In addition, the seed of the reaction tank may be to gradually decrease in size from the bottom to the top.

In addition, the microparticles present on the top of the seed of the reactor may be grown to the seed by crystallization on the surface of the microparticles over time.

In addition, the reaction tank, the separation tank, the settling tank are each cylindrical, the diameter of the reaction tank is smaller than the diameter of the separation tank, the diameter of the separation tank may be smaller than the diameter of the precipitation tank.

In addition, the separation tank may have a cylindrical tube shape extending in the vertical direction, and may have a plurality of protruding members extending in the horizontal direction with the tube as the central axis.

In addition, the plurality of protruding members may have a shape in which narrow protruding members are located at a lower portion, wide protruding members are positioned in an upper portion, or a narrow protruding member and a wide protruding member are alternately mixed. .

In addition, the fluid flow in the reactor may be a value calculated by Equation 1 below 4,000.

[Equation 1]

Re ₁ = D ₁ V ₁ ρ / μ

(Wherein D ₁ is the diameter of the reactor (m), V ₁ is the flow rate of the reactor (m / sec), ρ is the density (kg / m ³ ), and μ is the viscosity (kg / ms).)

In addition, the fluid flow in the separation tank may be a value calculated by Equation 2 below 2,100 to less than 4,000.

[Equation 2]

Re ₂ = D ₂ V ₂ ρ / μ

(Where D ₂ is the diameter of the separation vessel (m), V ₂ is the flow velocity of the separation vessel (m / sec), ρ is the density (kg / m ³ ) and μ is the viscosity (kg / ms).)

In addition, the fluid flow in the settling tank may be a value calculated by Equation 3 below 2,100.

[Equation 3]

Re ₃ = D ₃ V ₃ ρ / μ

(Where D ₃ is the diameter of the settling tank (m), V ₃ is the flow rate of the settling tank (m / sec), ρ is the density (kg / m ³ ) and μ is the viscosity (kg / ms).)

In addition, the fluid flow in the connection between the separation tank and the settling tank may be a value calculated by Equation 4 below 2,100.

[Equation 4]

Re ₄ = D ₄ V ₄ ρ / μ

(Wherein D ₄ is the diameter of the top of the separation tank or settling tank (m), V ₄ is the flow rate of the top of the separation tank or settling tank (m / sec), ρ is the density (kg / m ³ ), μ is the viscosity ( kg / ms).

In addition, the linear velocity of the separation vessel is 4.5 times or more based on the linear velocity of the sedimentation tank is less than 20 times, the linear velocity of the reaction vessel is 10 to 25 times the linear velocity of the sedimentation vessel, the upper linear velocity of the separation vessel and the linear velocity of the sedimentation vessel It can be equal or greater.

In addition, the linear velocity of the settling tank may be in the range of 1 ~ 7m / hr.

In addition, the treatment target water may be hydrofluoric acid-containing wastewater, phosphorus-containing wastewater, metal-containing wastewater, ammonia-containing wastewater, low salt water, anaerobic digestion process wastewater or hardness material-containing wastewater supplied to the lower side of the reactor through the raw water inlet.

In addition, the crystallization agent is supplied to the lower side of the reactor through the chemical inlet, sodium compounds (eg NaOH), calcium compounds (eg CaCl ₂ ), magnesium compounds (eg MgCl ₂ ) and phosphate compounds (eg, AlPO ₄ ) may be used one or more selected from.

In addition, the crystallization apparatus may be to circulate a part of the fluid of the separation tank to the reaction tank through the inner conveying pipe connected to the chemical inlet.

The crystallization method according to another embodiment of the present invention is a method of crystallizing the number of objects to be treated using the above-described crystallization device,

A seed filling step in which seeds are filled in the reactor;

A reaction step in which the water to be treated containing contaminants or ions and a crystallization agent react in a turbulent phase and crystallized on the seed surface, and the reactants not crystallized on the seed are formed as fine particles;

A separation step of returning some of the fine particles rising by buoyancy to the reactor in a stream in which laminar and turbulent flows together; And

It includes; a precipitation step of generating a laminar flow to precipitate the fine particles so that some of the fine particles rising by buoyancy does not flow out.

As described above, according to the embodiment of the present invention, instead of fabricating the fluid flow in the crystallization apparatus to be all laminar flow or all turbulent flow, the region in which the crystallization reaction mainly occurs and the region in which the solid-liquid separation reaction mainly occurs, The crystallization apparatus is designed to have a different fluid flow for each region where the precipitation reaction is mainly performed, so that the crystallization reaction is easy and the microparticles generated by the crystallization reaction are effectively maintained inside the apparatus without external leakage and grow into microcrystals. There is an effect of providing a crystallization apparatus and a crystallization method of the number.

In addition, the control of the fluid flow is well controlled to minimize the influence on the operation of the reactor.

Even if the effects are not mentioned here in detail, the effects described in the following specification and the tentative effects expected by the technical features of the present invention are treated as described in the specification of the present invention.

1 is a view showing a crystallization apparatus according to an embodiment of the present invention.
2 is a diagram illustrating forms applicable to a separation tank of a crystallization apparatus according to an embodiment of the present invention.
3 is a view illustrating forms applicable as a connection site of a reaction vessel and a separation vessel in a crystallization apparatus according to an embodiment of the present invention.
4 is a view illustrating the forms applicable to the connection portion of the separation tank and the settling tank in the crystallization apparatus according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the crystallization apparatus which concerns on this invention is demonstrated in detail with reference to drawings. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In addition, in order to clearly describe the present invention, parts irrelevant to the description are omitted, and like reference numerals in the drawings indicate like elements.

When a component is referred to as being "connected" or "equipped" to another component, it is to be understood that the component may be directly connected to or provided with the other component, but there may be other components in between. something to do.

Terms used in the following description, such as first and second, may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

First side

A first aspect of the invention relates to a crystallization apparatus.

1 is a view showing a crystallization apparatus according to an embodiment of the present invention.

Referring to Figure 1, the crystallization apparatus 10 according to an embodiment of the present invention is a reaction tank 100, separation tank 200, settling tank 300, raw water inlet 400, chemical inlet 500, It includes an inner conveying pipe 600, the treated water discharge portion 700.

The reactor 100, the separation tank 200, the settling tank 300 are each cylindrical, the diameter of the reaction tank 100 is smaller than the diameter of the separation tank 200, the diameter of the separation tank 200 is Smaller than the diameter of the precipitation tank 300 is preferred in the present invention can maximize the crystallization reaction efficiency and separation efficiency.

The reaction tank 100 is seeded in the crystallization device 10 according to an embodiment of the present invention, the target water (raw water) containing contaminants or ions supplied through the raw water inlet 400 And a chemical agent such as a crystallization agent supplied through the chemical inlet 500 reacts in a turbulent phase to crystallize on the seed surface, and the non-crystallized reactant on the seed corresponds to a base reactor in which a crystallization reaction is generated as microparticles. do.

The seed of the reactor 100 becomes smaller in size from the bottom to the top.

Microparticles present on the top of the seed of the reactor 100 is crystallized on the surface of the microparticles over time to grow into the seed.

That is, the first crystal formed by chemical reaction with the element at an appropriate pH is a few microns of fine particles, and stays at the point where the buoyancy and gravity due to the upflow are balanced. The microparticles continuously react with the injected element or the surrounding microparticles, and as the particle diameter gradually increases, the buoyancy becomes smaller than gravity and moves downward. The continuous injection of wastewater or liquid substances and chemicals containing the contaminants to be treated thus form fine grain crystals, and the growth and migration of these particles continuously occurs in one device.

The crystals moved to the lower part are grown and seeded by adsorbing the crystallized fine particles when the particle size continues to increase due to the reaction of liquid substance, waste water and injected chemicals in the lower part of the reaction tank of the crystallization device. In one-time injection, the crystallization reaction continues without injecting a separate seed.

When the seed is of constant size (or constant cycle), the crystals produced through the lower part of the crystallizer are extracted and the amount and volume of the filling in the reactor are kept constant.

For the stable and efficient crystallization operation in the above-mentioned crystallization reaction, an apparatus capable of stably maintaining the fine particles in the reaction vessel in which the crystallization reaction occurs is required. The present invention can prevent the microparticles from being present in the separation tank, which is a section where solid-liquid separation occurs in the fluid delivered from the reaction tank, and can stably maintain the fine particles in the reaction tank.

Specifically, the fine particles settle or rise depending on the sedimentation force (Fg = π / 6D _p ³ (ρ _p -ρ _w ) g) of the particle's own weight and the buoyancy (F = 3πμDpv) of the fluid moving from the bottom to the top. do. Therefore, in order to prevent the outflow of fine particles, the sedimentation force must be greater than buoyancy, and for this purpose, the weight of the particles must be increased (density increase) or the buoyancy must be weakened. Among them, it is effective to weaken the buoyancy because the weight increase of the particles cannot be achieved in a short time.

If you need to reduce the linear velocity of the fluid (v) To this end, when the increase in cross-sectional area when the flow rate is equal to the linear speed is decreased (Q = A ₁ V ₁ = V ₂ A ₂ in A is ₁ <A ₂ V _1> V ₂ ), so that the buoyancy can be weakened, and the larger the difference in linear velocity (ie, V ₁ >> V ₂ ), the smaller particles can be separated.

Therefore, the separation tank according to the embodiment of the present invention is configured to coexist with the turbulent region (or the transition region) and the laminar flow region, and as shown in FIG. 2 (a), the reactor is configured to repeat the turbulence-laminar flow, but the turbulence toward the top. In order to maximize the linear velocity difference between the layer and the laminar flow layer, it is desirable to further increase the diameter of the laminar flow layer.

In addition, the lower part is turbulent and the upper part deforms into a laminar flow toward the upper part, such as a shape in which the diameter increases uniformly toward the upper part (see FIG. 2 (b)) or a rapidly increasing diameter in the upper part (see FIG. 2 (c)). All forms can be included.

The fluid flow in the reactor 100 is preferably a value calculated by the following Equation 1 is more than 4,000 because the microparticles produced by the crystallization reaction can be grown into microcrystals while effectively maintaining the inside of the device without an external outflow.

[Equation 1]

Re ₁ = D ₁ V ₁ ρ / μ

(Wherein D ₁ is the diameter of the reactor (m), V ₁ is the flow rate of the reactor (m / sec), ρ is the density (kg / m ³ ), and μ is the viscosity (kg / ms).)

As used herein, the terms density and viscosity, unless otherwise specified, refer to 998.23 kg / m ³ , the density of water at 20 ° C., and viscosity to 0.001016 kg / ms.

Water to be used in the present invention is supplied to the lower side of the reaction tank 100 through the raw water inlet 400, and may be a liquid material or various wastewater containing contaminants or ions that can be treated by crystallization, and the like. For example, the hydrofluoric acid-containing wastewater, phosphorus-containing wastewater, metal-containing wastewater, ammonia-containing wastewater, and hard material-containing wastewater may be used.

The contaminants or ions to be removed may include, but are not limited to, fluorine, ammonia, Ca ²⁺ , Mg ²⁺ , F ⁻ , and the like.

The crystallization agent is supplied to the lower side of the reaction tank 100 through the chemical inlet 500 is preferably injected with sand, the crystallization agent is variable depending on the type of pollutants or ions contained in the water to be treated In the case of containing ions such as NH ₄ ⁺ , Ca ²⁺ , Mg ²⁺ , F ⁻ , the crystallization agent may include sodium compound (NaOH), calcium compound (eg CaCl ₂ ), magnesium compound (eg MgCl ₂ ) and phosphate It is preferable to use at least one selected from phosphorus compounds (eg AlPO ₄ ) because it can perform proper pH adjustment and crystallization.

2 is a diagram illustrating forms applicable to the separation tank 200 of the crystallization apparatus according to an embodiment of the present invention.

Separation tank 200 is provided on the reaction tank 100, the laminar flow and turbulence coexist so as to convey some of the fine particles rising by buoyancy to the reaction tank 100, the returned fine particles are reaction tank (100) ) To be used again in the crystallization reaction.

The fine particles are settled or raised depending on the sedimentation force by the weight of the particles themselves and the buoyancy of the fluid moving from the bottom to the top, the sedimentation force must be greater than the buoyancy to prevent the outflow of the microparticles.

In order to increase the sedimentation force, the weight of the particles must be increased (density increase) or the buoyancy must be weakened. Since the weight increase of the particles cannot be made within a short time, it is effective to weaken the buoyancy.

To reduce the buoyancy, the linear velocity (v) of the fluid should be reduced.If the cross-sectional area is increased at the same flow rate, the linear velocity decreases, so the buoyancy can be weakened, and the larger the difference in linear velocity, the smaller the particles can be separated. Do.

The separation tank 200 is preferably configured to coexist with the turbulent region (or transition region) and the laminar flow region using this principle.

2 (a), 2 (b) and 2 (c) are diagrams exemplarily showing shapes of the separation tank 200 suitable for use as an embodiment of the present invention.

Separation tank 200 has a form of a tube extending in the vertical direction of the device, having a plurality of protruding members extending in the horizontal direction about the tube as a central axis, or the lower portion of the tube is narrower and the diameter toward the upper portion It is preferable to have a form which widens.

Referring to Figure 2 (a), the separation tank 210 according to an embodiment of the present invention has a tubular shape extending in the vertical direction of the reaction apparatus, is formed extending in the horizontal direction with the tube as the central axis The form which has a some protrusion member is shown.

The plurality of protruding members may have a shape in which narrow protruding members are located at a lower portion thereof, a wide protruding member is located at an upper portion thereof, or a narrow protruding member and a wide protruding member are alternately mixed.

For example, the narrow projecting member may have a diameter of 1.5 times or more than the diameter of the tube and at the same time have a diameter smaller than the average diameter of the separation tank.

In one example, the wide diameter protruding member may have a diameter greater than twice the diameter of the tube and at the same time larger than the average diameter of the separation tank.

According to (a) of FIG. 2, it is preferable to alternately include the turbulent flow separation tanks 210a, 220a, 230a and the laminar flow separation tanks 210b, 220b, 230b alternately, and specific reasons will be described later.

Here, the turbulent flow separation tanks 210a 220a and 230a have the same width D1, and the laminar flow separation tanks 210b, 220b, and 230b each have the width D2, D3, and D4 in order. D2 = D4> D3, D2> D3 = D4, D2 = D3> D4, but satisfying the relationship of D4> D3> D2 controls the classification of particles while controlling the rate of circulation It can strengthen and is more preferable.

In addition, it is preferable that D1 and D2 satisfy the relationship of D1 <D2 so as to alternately express laminar flow and turbulent flow.

Referring to Figure 2 (b) and (c), the separation tank 220 according to an embodiment of the present invention has a tube form extending in the vertical direction of the reactor, the lower portion of the tube is narrower toward the upper portion The diameter is shown to be wide, (b) the figure shows a uniformly increasing shape, and (c) the figure shows a sudden increase in the diameter of the upper portion.

Fluid flow in the separation tank 200 has a flow gradient larger than the turbulent flow or alternating layer flow from the portion connected to the reaction tank 100 to the portion connected to the settling tank 300 has separation efficiency It is desirable to maximize.

That is, the fluid flow in the separation tank is preferably a value calculated by Equation 2 above 2,100 to 4,000 or less because the microparticles produced by the crystallization reaction can be effectively grown in the microcrystals while maintaining the inside of the apparatus without an external outflow. .

[Equation 2]

Re ₂ = D ₂ V ₂ ρ / μ

(Where D ₂ is the diameter of the separation vessel (m), V ₂ is the flow velocity of the separation vessel (m / sec), ρ is the density (kg / m ³ ) and μ is the viscosity (kg / ms).)

Alternatively, the fluid flow in the connection portion between the separation tank and the settling tank has a value calculated by Equation 4 below 2,100 so that the microparticles produced by the crystallization reaction can be grown into microcrystals while effectively maintaining the inside of the device without external leakage. desirable.

[Equation 4]

Re ₄ = D ₄ V ₄ ρ / μ

(Wherein D ₄ is the diameter of the top of the separation tank or settling tank (m), V ₄ is the flow rate of the top of the separation tank or settling tank (m / sec), ρ is the density (kg / m ³ ), μ is the viscosity ( kg / ms).

As used herein, the upper portion of the separation tank 200 refers to a portion where the separation tank 200 and the settling tank 300 are connected unless otherwise specified.

Separation tank may be provided with an internal conveying pipe 600 for circulating some fluid extracted from the separation tank 200 to the chemical inlet 500. At this time, the inner conveying pipe 600 is more preferably provided at the upper end of the separation tank 200 does not interfere with the flow of the fine particles separated in the separation tank 200 is recycled to the reaction tank (100).

The pipe connecting the separation tank 200 and the internal conveying pipe 600 may have a drain valve, and in this case, there is an effect of facilitating circulation of the fine particles.

The settling tank 300 is provided above the separation tank 200, and causes the laminar flow to precipitate the fine particles so that some of the fine particles rising by buoyancy do not flow out.

The fluid flow in the settling tank is preferably a value calculated by Equation 3 below 2,100 because the fine particles generated by the crystallization reaction can be effectively grown in the microcrystals while remaining inside the device without an external outflow.

[Equation 3]

Re ₃ = D ₃ V ₃ ρ / μ

(Where D ₃ is the diameter of the settling tank (m), V ₃ is the flow rate of the settling tank (m / sec), ρ is the density (kg / m ³ ) and μ is the viscosity (kg / ms).)

As described above, in order to stably maintain the fine particles in the reaction tank 100 of the present invention, the diameter of the reaction tank 100 is smaller than the diameter of the separation tank 200, the diameter of the separation tank 200 It is preferable to be connected in order from the top while satisfying the relationship smaller than the diameter of the settling tank (300). In the case of having such a structure and diameter, even though the fine particles float upstream due to buoyancy, the fine particles are circulated a plurality of times in the reaction tank, which is advantageous to grow into microcrystals.

In one example, the diameter of the separation tank 200 may be 2 to 4 times larger than the diameter of the reaction tank 100.

For example, the diameter of the settling tank 300 may be greater than 4.5 times larger than the diameter of the reaction tank 100 at the same time greater than twice the diameter of the separation tank 200.

Here, the upper diameter of the separation tank 200 may be the same or smaller than the diameter of the settling tank 300, the diameter of the reaction tank 100 may be based on a specific example of 5 ~ 20cm, but is variable.

In addition, the linear speed of the separation tank 200 may be, for example, less than 20 times 4.5 times based on the linear speed of the settling tank.

In addition, the linear velocity of the reaction tank 100 may be 10 to 25 times as an example of the linear velocity of the precipitation tank 300.

Here, the upper linear velocity of the separation tank 200 may be the same as or greater than the linear velocity of the precipitation tank 300, the linear velocity of the precipitation tank 300 may be based on, for example, 1 ~ 7m / hr.

3 is a view illustrating forms applicable as a connection site of the reaction tank 100 and the separation tank 200 in the crystallization apparatus according to an embodiment of the present invention.

Referring to Figure 3 (a), it illustrates a structure in which the connection portion of the reaction tank 100 and the separation tank 200 according to an embodiment of the present invention has a linear tapered shape.

Microparticles, etc. separated in the separation tank 200 through the connection site can be easily provided to the reaction tank 100 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

Referring to Figure 3 (b), it illustrates a structure in which the connection portion of the reaction tank 100 and the separation tank 200 according to an embodiment of the present invention has a curved tapered shape.

Microparticles, etc. separated in the separation tank 200 through the connection site can be easily provided to the reaction tank 100 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

Referring to Figure 3 (c), it illustrates a structure in which the connection portion of the reaction tank 100 and the separation tank 200 according to an embodiment of the present invention has a cross-curved tapered shape.

Microparticles, etc. separated in the separation tank 200 through the connection site can be easily provided to the reaction tank 100 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

4 is a view illustrating forms applicable as a connection site of the separation tank 200 and the settling tank 300 in the crystallization apparatus according to an embodiment of the present invention.

Referring to Figure 4 (a), it illustrates a structure in which the connection portion of the separation tank 200 and the settling tank 300 according to an embodiment of the present invention has a linear tapered shape.

Through the connection site, the microparticles separated from the settling tank 300 may be easily provided to the separation tank 200 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

Referring to Figure 4 (b), the connection part of the separation tank 100 and the settling tank 300 according to an embodiment of the present invention illustrates a structure having a curved tapered shape.

Through the connection site, the microparticles separated from the settling tank 300 may be easily provided to the separation tank 200 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

Referring to Figure 4 (c), it illustrates a structure in which the connection portion of the separation tank 100 and the settling tank 300 according to an embodiment of the present invention has a cross-curved tapered shape.

Through the connection site, the microparticles separated from the settling tank 300 may be easily provided to the separation tank 200 according to the circulating flow of the fluid.

Through the tapered angle and the specific shape of the corresponding site can effectively provide the separation of the fine particles. In one example, the taper angle may be an angle of 45 ° to 90 °.

In the conventional case, generally, fine particles are concentrated in a section in which the reactor is expanded. In this case, since there is an excessive amount of fine particles to be separated in the separation tank, the treatment efficiency of the separation tank is inevitably reduced, and as a result, the crystallization efficiency is lowered.

delete

Second side

A second aspect of the present invention relates to a method for crystallizing the number of objects to be treated using the above-described crystallization apparatus.

For example, it may be performed in the following order, and description overlapping with the first side will be omitted below.

First, as a seed filling step, seeds are filled in the reactor. In other words, a reaction material (Seed) is added at the beginning of the reaction, but is characterized by one-time injection.

Subsequently, as a reaction step, the water to be treated including the contaminants or ions in the reactor and the crystallization agent react in a turbulent phase to crystallize on the seed surface, and the reactant that is not crystallized on the seed is produced as microparticles.

Subsequently, as a separation step, some of the fine particles rising by buoyancy are returned to the reactor in a stream in which laminar flow and turbulent flow coexist.

Next, as a precipitation step, the microparticles are precipitated by generating laminar flow so that some of the microparticles rising by buoyancy do not flow out.

Further, in the separating step, a part of the fluid is recycled to the lower portion of the reactor through the inner conveying tube.

Hereinafter, preferred examples are provided to aid in understanding the present invention, but the following examples are merely for exemplifying the present invention, and various changes and modifications within the scope and spirit of the present invention are apparent to those skilled in the art. It is natural that such variations and modifications fall within the scope of the appended claims.

Example

The crystallization method was performed using the crystallization apparatus 10 shown in FIG.

The crystallization apparatus 10 is based on the design of the reaction tank 100, the separation tank 200, the precipitation tank 300 to be described later.

That is, the reactor 100 was designed with a diameter of 13 cm and a linear speed of 70 m / hr. As a result of the calculation using the following equation, it was possible to confirm the turbulent flow in the reactor 100 as the Reynolds number more than 4,000.

Re = 0.13m x Π x 70m / hr x 998.23 kg / m3 / 0.001016 kg / m.s

= 8,094.5 (turbulent)

In addition, the separation tank 200 was designed at a diameter of 29 cm and a linear velocity of 15 m / hr. At this time, the connection portion between the reaction tank 100 and the separation tank 200 was used in the form having a plurality of protruding members shown in Figure 2 (a) and the connection angle was set to 90 °. As a result of the calculation using the following equation, as the Reynolds number of more than 2,100 or less than 4,000, the transition region flow in the separation tank 200 could be confirmed.

Re = 0.29m x Π x 15m / hr x 998.23 kg / m3 / 0.001016 kg / m.s

= 3,747 (transition region)

In addition, the upper part of the separation tank 200 and the settling tank 300 corresponding to the connection portion of the separation tank 200 and the settling tank 300 were designed to have a diameter of 60 cm and a linear speed of 3.5 m / hr. At this time, the connection portion between the separation tank 200 and the settling tank 300 was a connection angle of 90 °. As a result of the calculation using the following equation, it was possible to check the laminar flow in the upper part of the separation tank 200 and the sedimentation tank 300 as Reynolds number 2,100 or less.

Re = 0.60m x Π x 3.5m / hr x 998.23 kg / m3 / 0.001016 kg / m.s

= 1,810 (laminar flow)

Waste water containing NH ₄ ⁺ , Ca ²⁺ , Mg ²⁺ , F ^−, etc., as the treatment target water was continuously injected into the crystallization device 10 designed as described above through the raw water inlet unit 400, As the crystallization agent, sodium compound (NaOH), calcium compound (CaCl ₂ ), magnesium compound (MgCl ₂ ), and phosphate compound (AlPO ₄ ) are continuously injected along with sand through the chemical inlet 500 for 2 hours. Was performed.

During the reaction, a part of the fluid was periodically extracted from the internal transport unit 600 provided at the top of the separation tank 200 and recycled to the chemical injection unit 500.

In addition, the crystals generated at regular intervals were extracted through the lower portion of the reactor 100 to maintain a constant amount and volume of the filler in the reactor 100.

Comparative example

In the above example, the same process as in the above example was repeated except that the crystallizer designed to provide turbulent flow to both the separation tank 200 and the sedimentation tank 300 was used.

Experimental Example

After 2 hours of operation, the treated water discharged through the treated water discharge part 700 was examined. As a result, CaCO ₃ , MgCO ₃ , MgNH ₄ PO ₄ , Ca ₃ (PO ₄ ) ₃ , The content of fine particles such as CaF was detected at 1.5 NTU, whereas the content of fine particles such as CaCO ₃ , MgCO ₃ , MgNH ₄ PO ₄ , Ca ₃ (PO ₄ ) ₃ , CaF in the treated water discharged from the comparative example It confirmed that it detected by 6.4NTU.

As a result, the crystallization apparatus according to the embodiment of the present invention was able to confirm the effect of effectively preventing the external outflow while maintaining the fine particles in a stable manner.

The above description is only one embodiment of the present invention, and those skilled in the art may implement the present invention in a modified form without departing from the essential characteristics of the present invention. Therefore, the scope of the present invention should not be limited to the above-described examples, but should be construed to include various embodiments within the scope equivalent to those described in the claims.

10: crystallization device
100: reactor
200: separation tank
210a, 220a, 230a: Turbulent Flow Separators
210b, 220b, 230b: laminar flow separation tank (protrusion member)
300: sedimentation tank
400: raw water inlet
500: chemical inlet
600: internal return pipe
700: treated water discharge part

Claims (17)

A reaction tank in which a seed is filled therein so that the water to be treated including contaminants or ions and a crystallization agent react in a turbulent phase to crystallize on the seed surface, and the reactant that is not crystallized on the seed is produced as microparticles;
A separation tank provided on the reaction tank and having laminar flow and turbulent flow coexisting to return some of the fine particles rising by buoyancy to the reaction tank; And
And a sedimentation tank provided above the separation tank and generating a laminar flow so as to prevent some of the microparticles rising by buoyancy from flowing out to precipitate the microparticles.
The fluid flow in the separation tank has a connecting portion for supplying the settling tank by changing the value calculated by the following equation 4 to 2,100 or less to the treated object water value is calculated by the following equation 2 is greater than 2,100 to 4,000 or less ,
And an internal conveying tube for recirculating a part of the fluid including the microparticles in the separation tank to the lower portion of the reaction tank.
[Equation 2]
Re ₂ = D ₂ V ₂ ρ / μ
(Where D ₂ is the diameter of the separation vessel (m), V ₂ is the flow velocity of the separation vessel (m / sec), ρ is the density (kg / m ³ ), and μ is the viscosity (kg / ms).)
[Equation 4]
Re ₄ = D ₄ V ₄ ρ / μ
Where D ₄ is the diameter of the top of the separator (m), V ₄ is the flow rate (m / sec) at the top of the separator, ρ is the density (kg / m ³ ), and μ is the viscosity (kg / ms) to be.) The method of claim 1,
The seed of the reactor is a crystallization apparatus of the water to be treated gradually decreases in size from the bottom to the top. The method of claim 2,
And crystallizing the microparticles present on the top of the seed of the reaction tank on the surface of the microparticles over time to grow into the seed. The method of claim 3,
The reactor, the separation tank and the settling tank are each cylindrical, the diameter of the reaction tank is smaller than the diameter of the separation tank, the diameter of the separation tank is smaller than the diameter of the precipitation tank crystallization apparatus. The method of claim 4, wherein
The separation tank has a form of a cylindrical tube extending in the vertical direction, the crystallization apparatus of the number of objects having a plurality of protruding members extending in the horizontal direction about the tube as a central axis. The method of claim 5,
The plurality of protruding members may include narrow protruding members at lower portions, wide protruding members at upper portions thereof, or narrow protruding members and wide protruding members having alternating shapes. Crystallization device. The method of claim 1,
The fluid flow in the reactor is a crystallization apparatus of the water to be treated with a value calculated by Equation 1 below 4,000
[Equation 1]
Re ₁ = D ₁ V ₁ ρ / μ
(Wherein D ₁ is the diameter of the reactor (m), V ₁ is the flow rate of the reactor (m / sec), ρ is the density (kg / m ³ ), and μ is the viscosity (kg / ms).) delete The method of claim 1,
The fluid flow in the sedimentation tank is a crystallization apparatus of the water to be treated whose value calculated by Equation 3 is 2,100 or less
[Equation 3]
Re ₃ = D ₃ V ₃ ρ / μ
(Where D ₃ is the diameter of the settling tank (m), V ₃ is the flow rate of the settling tank (m / sec), ρ is the density (kg / m ³ ) and μ is the viscosity (kg / ms).) delete The method of claim 1,
The linear velocity of the separation vessel is 4.5 times or more and less than 20 times the linear velocity of the sedimentation vessel, the linear velocity of the reaction vessel is 10-25 times the linear velocity of the sedimentation vessel, and the upper linear velocity of the separation vessel is the same as the linear velocity of the sedimentation vessel or The crystallization apparatus of the processing object number which is large. The method of claim 11,
The crystallization apparatus of the water to be treated is the linear velocity of the settling tank is 1 ~ 7m / hr. The method of claim 1,
And the water to be treated is hydrofluoric acid-containing wastewater, phosphorus-containing wastewater, metal-containing wastewater, ammonia-containing wastewater, or light matter-containing wastewater which is supplied to the lower side of the reactor through a raw water inlet. The method of claim 13,
The crystallization agent is supplied to the lower side of the reaction tank through the chemical inlet, crystallization apparatus of the treated water of at least one selected from sodium compounds, calcium compounds, magnesium compounds and phosphate compounds. The method of claim 1,
The inner conveying pipe is a crystallization apparatus of the water to be treated connected to the chemical inlet. delete A method for crystallizing the number of objects to be treated using the crystallization apparatus of claim 1,
A seed filling step in which seeds are filled in the reactor;
A reaction step in which the water to be treated containing contaminants or ions and a crystallization agent react in a turbulent phase and crystallized on the surface of the seed, and the reactant not crystallized on the seed is generated as fine particles;
A separation step of returning some of the fine particles rising by buoyancy to the reactor in a stream in which laminar and turbulent flows together;
A precipitation step of generating laminar flow to precipitate the fine particles so that some of the fine particles rising by buoyancy do not flow out; And
And circulating a portion of the fluid in the separation tank to the lower portion of the reaction tank.

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