KR101612219B1 - Device and Method for Treating Washing Water using combined coagulation-ceramic ultrafiltration membrane system - Google Patents

Abstract

The present invention relates to a method and an apparatus for treating washing water using a coagulation-ceramic ultrafiltration membrane. The water treated by the method and the apparatus can be reused as washing water. According to the present invention, the method for treating washing water is characterized by sequentially carrying out the following processes: a coagulation-combined ceramic ultrafiltration membrane process including a coagulation process and a ceramic filtration membrane process; an ion exchange process; and a reverse osmosis (RO) pressure type filtration process. The production of high quality and ultrapure production water is possible by the method for treating waste water, and the method can reduce membrane fouling in the rear stage processes ( an ion exchange system, RO process), which further leads to reduction in operation costs.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to an apparatus and a method for treating wastewater using a coagulating-ceramic ultrafiltration membrane,

The present invention relates to an apparatus and a method for treating wastewater using a coagulated-ceramic ultrafiltration membrane, and the treated water can be reused as wash water.

With the rapid development of industry, industrial forms are diversifying, and the type and discharge amount of industrial wastewater are also increasing. Therefore, in order to preserve and secure limited water resource, it is required to develop the technology for the wastewater treatment and reuse field. Recently, with the development of filtration membrane manufacturing technology, wastewater reuse technology using filtration membranes in water and industrial wastewater fields has been expanded.

 The plating wastewater contains a large amount of metallic material, unlike other industrial wastewater, and is characterized in that the characteristics and amount of the plating wastewater by the plating process are different. Among them, the plating water generated in the plating degreasing process accounts for a large amount of the amount of the plating wastewater generated and contains a large amount of surfactant in order to remove oxides, hydroxides and oils adhering to the metal surface.

Currently, ion exchange systems and reverse osmosis filtration processes (RO processes) are being used to reuse plating water. Appropriate pretreatment is important because the durability and performance of ion exchange membranes are directly affected by the incoming water quality. In the case of activated carbon used as pretreatment water, the particle surface is negatively charged and is not effective in the treatment of anionic surfactants. In addition, when organic materials and colloidal materials that can not be removed from the activated carbon process and the ion exchange system, which are RO shearing processes, are introduced into the RO membrane module, membrane contamination is caused and the filter membrane performance is deteriorated.

If the plating water is introduced into the ion exchange system and the RO process without proper pretreatment, it causes film contamination in the process and increases the operating cost due to the decrease in the production quantity of reused water.

The present invention aims at minimizing membrane contamination in the ion exchange system, RO process, which is a downstream process, by removing the organic substances contained in the wash water by applying the cohesion-bonding type ceramic ultrafiltration membrane process to the wash water pretreatment process.

A first aspect of the present invention is a coagulation-bonding type ceramic ultrafiltration membrane process comprising an aggregation process and a ceramic filtration process; Ion exchange membrane process; And a reverse osmosis filtration membrane process are sequentially carried out.

A second aspect of the present invention is a method for neutralizing alkaline plating water, comprising the steps of: A mixing tank for rapidly mixing the neutralized plating water with the flocculant; A pH adjusting tank which rapidly mixes the pH adjusting solution used to adjust the optimal flocculation pH of the plating water discharged from the mixing tank; A ceramic single surgical membrane separating the plating water discharged from the pH adjusting tank into water and fl ow without a coagulating bath and a settling tank for separate relaxation mixing; Ion exchange membranes; And a reverse osmosis filtration membrane are provided in the order of process.

A third aspect of the present invention provides a wastewater treatment method characterized in that the wastewater containing an organic substance is subjected to the following steps in sequence:

Optionally neutralizing the alkaline wastewater in the neutralization tank; Admixing the coagulant in a mixing tank and mixing with neutral wastewater; And agglomerating the wet wastewater treated in the pH adjusting tank with a pH adjusting solution so as to adjust the optimum aggregating pH;

a ceramic filtration membrane process for treating wastewater discharged through the coagulation process without separately passing through a flocculation tank and a sedimentation tank requiring a lower mixing rate than a pH adjustment tank;

Ion exchange membrane process; And

Reverse Osmosis Filtration Membrane Process.

Hereinafter, the present invention will be described in detail.

The electrical desalination technique using an ion exchange membrane is a method in which a cation exchange membrane and anion exchange membrane are alternately installed in a membrane module and a voltage is applied to both electrodes of the module to selectively transmit the positive ions and anions dissolved in the water using electric force Based process technology. Ion exchange membrane processes have been applied in various industrial fields such as the removal of heavy metals in industrial wastewater, the desalination of seawater, and the production of ultrapure water in the semiconductor industry.

Electrodialysis using an ion exchange membrane is a process for separating ionic substances dissolved in water by using an electric field formed by a direct current power supplied through an electrode and an electrolyte solution. The ion exchange membrane used here indicates the selective permeability of the corresponding ions by the ionic bonding of the fixed ions in the membrane in the electrolyte solution. In general, ion exchange membranes are required to have high permeability selectivity, low electrical resistance, excellent mechanical strength, and high chemical stability. Ion exchange membranes are mainly composed of polymeric materials and inorganic materials. They are classified into cation exchange membranes and anion exchange membranes depending on the membrane functional groups. The cation exchange membrane selectively permeates cations and has negative charge functional groups such as SO ₃ , COO, PO ₃ ² , PO ₃ H and C ₆ H ₄ O. On the other hand, the anion exchange membrane has positive charge functional groups such as NH ₃ ⁺ , NRH ₂ ⁺ , NR ₂ H ⁺ , NR ₃ ⁺ , PR ₃ ⁺ , and SR ₂ ⁺ . Electrodialysis using an ion exchange membrane has been widely used as a mechanism for separating and purifying an ionic substance in an aqueous solution.

The reverse osmosis membrane has a pore size of 0.001 ~ 0.0001, and the feed water from one end of the membrane surface to the other end of the membrane surface for various organic substances, inorganic substances, particulate matter, turbidity components, bacteria, bacteria, It has a function to remove more than 98% of pollutants with a thin film that causes the phenomenon. The reverse osmosis membrane is composed of a supporting layer and an active layer having a separating function, and separates the solvent and the solute using reverse osmosis.

On the other hand, reverse osmosis technology (ROT) can recover plating chemicals from plating water. The semipermeable membrane is used to transport water molecules, but water molecules can not pass through metal salts and additives. Reverse osmosis technology is the best technique for dilute solutions. In addition, the capacity and design conditions for reverse osmosis depend on the type of chemical and the flow rate of the drag-out solution. Polyamide membrane is suitable for zinc chloride and wattage nickel, and polyester / amide membrane is suitable for chromic acid and acidic copper solution. Therefore, reverse osmosis technology shows a recovery rate of 95% under optimal conditions. One advantage of reverse osmosis technology is that it consumes less energy than other recovery technologies. It is possible to recover the plating agent from the temperature-sensitive solution. Disadvantages are that the membrane is highly susceptible to membrane fouling caused by suspended solids or dissolved solids. In addition, since the impurities are concentrated together with the plating agent, the plating quality may be deteriorated.

The wastewater treatment method, such as plating wastewater according to the present invention, includes an ion exchange membrane process; And a pretreatment process before the reverse osmosis filtration membrane process is characterized in that the coagulation-bonding type ceramic ultrafiltration membrane process is composed of an agglomeration process and a ceramic filtration process.

The coagulation-bonding type ceramic ultrafiltration membrane process

Optionally neutralizing the alkaline wastewater in the neutralization tank; Admixing the coagulant in a mixing tank and mixing with neutral wastewater; And agglomerating the wet wastewater treated in the pH adjusting tank with a pH adjusting solution so as to adjust the optimum aggregating pH; And

and a ceramic filtration membrane process for treating wastewater discharged through the coagulation process without separately passing through a flocculation tank and a sedimentation tank requiring a lower mixing rate than the pH control tank (FIG. 1).

Further, the plating water washing water treatment method according to the present invention

A neutralization tank for neutralizing the alkaline plating water;

A mixing tank for rapidly mixing the neutralized plating water with the flocculant;

A pH adjusting tank which rapidly mixes with the pH adjusting solution to adjust the optimum flocculation pH of the plating water discharged from the mixing tank;

A ceramic single surgical membrane separating the plating water discharged from the pH adjusting tank into water and fl ow without a coagulating bath and a settling tank for separate relaxation mixing;

Ion exchange membranes; And

And a reverse osmotic filtration membrane are provided in the order of process.

The coagulation-bonding type ceramic ultrafiltration membrane process according to the present invention is classified into an aggregation process and a ceramic filtration process.

Preferably, in the plating water wastewater treatment method according to the present invention, the flocculation process includes neutralizing the alkaline plating wastewater in the neutralization tank; Admixing the coagulant in the mixing tank and mixing with the neutralized plating wastewater; And a step of injecting and mixing the pH adjusting solution so as to adjust the optimum flocculation pH to the flocculant treated water in the pH adjusting tank.

The optimum flocculation conditions (pH, amount of flocculant used) can be calculated through the method shown in Fig.

Water with high alkalinity has a large number of hydroxide ions, which interfere with the binding of negatively charged contaminants to positively charged coagulants. In order to prevent deterioration of coagulation efficiency due to alkalinity in the flocculation process, a neutralization tank is placed in the mixing tank to neutralize the highly alkaline water.

The alkaline plating water can be neutralized using acids such as hydrochloric acid, sulfuric acid, and carbon dioxide gas.

The neutralized wastewater is rapidly admixed with a flocculant for the formation of flocs in a mixing tank. External energy is required for the coagulation to occur smoothly and is expressed as a velocity gradient (G, sec-1). In addition, sufficient flocking time (t, sec) must be given for smooth flock growth in the mixing tank. The Gt (dimensionless) value of typical aggregation is known as 10,000 to 100,000. If the blend strength is too great, it is important to determine the appropriate range of speed slope and time since flocs may break.

Non-limiting examples of coagulants include polyaluminium chloride (PACl), polyaluminium chloride silicate, polyaluminium chloride chloride, ferric chloride, ferrous chloride, ferric sulfate, ferrous sulfate, Alum .

In the pH control tank, when a pH adjusting agent is added to rapidly mix to adjust the optimal flocculation pH, the contaminants contained in the washing water are combined with the flocculant to form a floc. The rapid mixing strength in the pH adjusting tank may be the same as the mixing tank. Optimum flocculation pH may vary depending on raw water and flocculant. The plating water is characterized by containing a large amount of a surfactant having a small molecular weight, and such a material is hardly removed by a general coagulation process. In some acidic conditions (pH <6), the coagulant is present in either monomeric or medium polymer form, which forms a complexation with small contaminants in the water and enhances the flocculation effect. On the other hand, when pH in water is high during flocculation, the flocculant is present in the sol or gel state and is not easy to remove small contaminants.

Non-limiting examples of pH adjusting agents include hydrochloric acid, sulfuric acid, carbon dioxide gas, sodium hydroxide, slaked lime, soda ash, and calcium carbonate.

In addition, through the coagulation process according to the present invention, the plating water for neutralizing alkaline plating water, admixing it with the flocculant, and then adjusting the optimum flocculation pH can be applied to the ceramic filtration process without passing through another flocculation tank and a settling tank have.

According to the present invention, membrane filtration process using a polymer membrane for the effluent discharged from the coagulation process results in low flux, frequent membrane washing due to membrane fouling, There arises a problem that the replacement frequency is increased and the film durability is increased due to the increase of inter-membrane pressure.

Meanwhile, the ceramic filter membrane (FIG. 6) used in the present invention is made of a sintered inorganic material. A ceramic film of titanium oxide, aluminum oxide (alumina) or zirconium oxide (zirconia) is put into practical use.

The raw water flows from one side of the ceramic membrane, passes through a plurality of raw water channels, and the purified water is filtered, and the unfiltered material in the raw water is left in the ceramic membrane.

Since ceramic membranes are made by sintering fine ceramic particles, the size of the pores is determined by the size of the particles, from UF membranes with small pores to MF membranes with large pores. In addition, it is possible to operate high flux, high recovery rate and low energy, and it is easy to maintain because it is resistant to heat resistance, chemical resistance, corrosion resistance, resistance against microorganisms, etc. Therefore, it can reduce operating expenses such as manpower cost, .

Due to the heat resistance, chemical resistance and durability of the ceramic film, the present invention can be applied not only to the plating water washing water but also to industrial wastewater in various fields. The ceramic membrane is also easy to combine with the advanced oxidation treatment used to remove trace contaminants.

On the other hand, as shown in Table 2, there is little difference in COD and TOC removal efficiencies depending on the presence or absence of the flocculation tank and the sedimentation tank between the flocculation process and the ceramic filtration process according to the present invention. Therefore, since the treatment method according to the present invention does not include a flocculation tank and a sedimentation tank, it is possible to reduce the site area and at the same time to exhibit COD and TOC removal efficiencies similar to those of the treated water which maintains high flux and has undergone flocculation- have.

Furthermore, the effluent from the flocculation process with rapid mixing is flocculated on the surface of the ultrafiltration membrane of the ceramic and coagulant. However, the effluent discharged from the flocculation tank and the sedimentation tank is not separated from the ceramic ultrafiltration membrane It accumulates or adsorbs in the pore, which causes the flux to drop sharply.

In the coagulation-bonding type ceramic ultrafiltration membrane process according to the present invention, the flocs formed in the coagulation process can be separated in the ceramic filtration process.

The plating water to be treated may contain a large amount of surfactant to remove oxides, hydroxides, and oils adhering to the metal surface during plating. The surfactant in monomer form is too small to pass through the filter membrane and can not be removed. However, after the process of the cohesion-bonding type ceramic ultrafiltration membrane according to the present invention, wastewater such as plating water can be removed more than 80% of organic and colloidal materials. In the examples, COD and TOC were measured to indirectly measure an anionic surfactant, which is one kind of organic material.

Accordingly, the coagulation-bonding type ceramic ultrafiltration membrane process according to the present invention not only effectively removes the anionic surfactant but also minimizes the membrane contamination that may occur in the post-stage process (ion exchange system, RO process) Performance can be improved.

The microfilter may further include a step of removing suspended solids contained in wastewater, such as plating water, before the coagulation-bonding type ceramic ultrafiltration membrane process according to the present invention.

Hereinafter, with reference to Fig. 1, a method of treating plating wastewater according to one embodiment of the present invention will be described.

First, the plating water wash water (1) flows into the microfilter (2) along the pipe and is filtered, and the suspended substances contained in the wash water are primarily removed.

In the coagulation process, a neutralization tank 3 for neutralizing water with high alkalinity (pH 11 to 12), a mixing tank (coagulant administration) for forming a floc, and a pH adjusting tank are arranged in this order. And a ceramic filtration membrane process that separates the flocs formed in the coagulation process.

 The effluent water from which the suspended solids are removed flows into the neutralization tank (3), and the pH of the plating water is neutralized to 7 by the sulfuric acid (4). The neutralized water wash water flows into the mixing tank 5. In the mixing tank, the flocculant (ferric chloride) (6) is added to the mixing tank and the rapid mixing is carried out. The flocculant and the rapid water-miscible water are introduced into the pH adjustment tank 7 to adjust the optimum flocculation pH. In the pH control tank, water is adjusted to the optimum pH by the pH adjusting solution (sulfuric acid, sodium hydroxide) (8).

 The flocs formed only through the rapid mixing without passing through the flocculation tank (full mixing) and the settling tank are separated into the treated water and the fl ow through the ceramic filtration membrane.

The micro flocs 9 generated through the mixing tank 5 and the pH adjustment tank 7 are filtered through the ceramic ultrafiltration membrane 10 without passing through the flocculation tank ) Is generated. The generated treated water 11 flows into the ion exchange system 12 and RO process 13, which are the post-stage processes.

By the wastewater treatment method of the present invention, it is possible to produce high-quality production water at the level of ultra-pure water and to reduce the membrane contamination in the downstream process (ion exchange system, RO process), thereby reducing operating costs.

In addition, by using the apparatus for treating wastewater according to the present invention, it is possible to improve the plating quality and the treatment efficiency of the plating wastewater through a thorough water quality management at low cost.

In addition, the improvement of product quality due to the increase of washing water volume, the decrease of the amount of wastewater generation, and the reuse of water can increase the corporate image.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a configuration diagram of a plating water and wastewater treatment apparatus according to one embodiment of the present invention. FIG.
2 is a configuration diagram of a plating water and wastewater treatment apparatus provided with a flocculation tank and a settling tank as a comparative example.
3 is a graph showing the difference in COD and TOC removal efficiencies depending on the presence or absence of neutralization (NT: neutralization tank).
FIG. 4 is a graph showing the difference in COD and TOC removal efficiency according to the type of coagulant.
5 is a graph showing flux and flux recovery rate differences according to operating conditions.
6 is a schematic diagram of a ceramic filter membrane that can be used in one embodiment of the present invention.
Fig. 7 shows an example of a method of finding the optimum flocculation condition.
8 is a schematic diagram for performing a performance test of the coagulated-ceramic ultrafiltration membrane system according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are for further illustrating the present invention, and the scope of the present invention is not limited by these examples.

Example 1 _ Comparing COD and TOC removal efficiency according to neutralization condition

Water from the waste water was collected at an electrolytic plating plant located in Incheon, and stored at 4 캜, and treated with water according to the process shown in Fig.

The suspended material contained in the wash water was removed with a 1 [mu] m cartridge filter.

The pH of the feed water to be treated with suspended solids is 11.98, the alkalinity is 3183 mg / L (as CaCO ₃ ), the COD (Chemical Oxygen Demand) is 422 mg / L and the total organic carbon (TOC) 245.05 mg / L.

 In the neutralization tank, the high pH (11 ~ 12) of the wash water was neutralized (pH 7) by sulfuric acid which is a pH regulating agent.

Thereafter, the mixture was rapidly mixed at 250 rpm for 2 minutes in which the flocculent FeCl ₃ was added to the neutralized water in the mixing tank. FeCl ₃ is an inorganic coagulant that can lower the pH of water and hence the pH in the water becomes weakly acidic. When the pH in the water is weakly acidic, the inorganic coagulant is present as a monomer or medium polyer, which combines with small contaminants in the water to form a flock.

To make the optimum pH environment so that the formed flakes were well maintained, a predetermined pH control solution was added for 30 seconds while rapidly mixing in a pH adjustment bath.

Next, for the filtration, a TAMI ceramic ultrafiltration membrane (INSIDE DISRAM ^TM , TAMI INDUSTRIES, France) having a ceramic flat membrane was subjected to the same operation conditions as shown in Table 1 for one cycle in the experimental setup as shown in FIG. 8 I was driving for 30 minutes. In FIG. 8, nitrogen gas was used to keep the pressure constant, and the permeate of the ceramic filtration membrane was collected to calculate the flux.

In order to evaluate the cohesion bonding type ultrafiltration membrane system, the recovery rate of the flux was examined by removing the gel layer accumulated on the membrane surface after operation and backwashing.

Support TiO ₂ Membrane ZrO ₂ TiO ₂ Molecular weight cut off 50,000 and 150,000 Da
(50 kDa, 150 kDa) Thickness 2.2 mm Effective area 0.00131 m ² Operation pressure 1 bar Operation temperature <130 ° C Operation mode Dead-end filtration pH range 2 - 14

As can be seen from FIG. 3, it can be seen that the efficiency of removing COD and TOC varies depending on the presence or absence of neutralization tank even when the same amount of coagulant is used. In the process including the neutralization tank, the efficiency of flocculation was higher than that of the flocculant even if a smaller amount of flocculant was used. In other words, in order to coagulate the coagulant with highly alkaline wastewater, it is effective to increase the coagulation efficiency by firstly lowering the pH of the wastewater by placing a neutralization tank.

Example 2 _ Difference in Removal Efficiency According to Coagulant Type

A water bath was treated in the same manner as in Example 1 except that a neutralization tank was used and the type of coagulant was changed.

As shown in FIG. 4, when the neutralization tank was placed in the mixing tank, the difference in removal efficiencies of COD and TOC was confirmed according to the type of coagulant.

The reason for the difference in the coagulation efficiency is that PACl hydrolyzes the Al ions contained in the PACl and is mostly present in hydroxide form. Coagulants, which are hydrolyzed predominantly in the form of hydroxides, remove contamination in the water through bridging or flocculation mechanisms. However, in the case of the surfactant contained in the plating water, the size of the pollutant is small and it is difficult to remove it by the above mechanism. However, in the case of FeCl ₃ , when the pH in water is low, the coagulant is present in the form of monomeric species or medium polymer species. This is effective for removal of small-sized contaminants, so that COD and TOC removal efficiency is higher than PACl. At this time, the eliminator is deduced to be small complexation, adsorption, charge neutralization and co-precipitation.

Example 3 _ Difference in Plus, Removal Efficiency, and Flux Recovery (Surface Cleaning) according to Operation Process Variation

FIG. 5 shows the result of operating a ceramic ultrafiltration membrane for 30 minutes at a pressure of 1 bar (TMP) using FeCl ₃ as a coagulant. The types of operation processes are divided into a process of FIG. 1 and a process of FIG. 2.

The difference between the processes of FIG. 1 and FIG. 2 is the presence of the flocculation tank and the sedimentation tank at the downstream of the pH adjustment tank.

2, the role of the coagulation tank 9 and the settling tank 11 are as follows. In the coagulation tank (9), the micro flocs (10) produced in the mixing tank and the pH adjusting tank are made into giant flocs (10). In the settling tank (11), they are precipitated and solid-liquid separated and the supernatant liquid (12) is sent to the ceramic ultrafiltration membrane.

As can be seen from FIG. 5, when the water flowed into the ceramic ultrafiltration membrane through only the rapid mixing process (FIG. 1), the flux was higher than that of the supernatant (the process of FIG. 2), and the physical cleaning (surface cleaning + backwashing) It was confirmed that the flux recovery rate was high.

  In the rapid mixing process, flocs composed of contaminants and coagulants are accumulated on the surface of the ultrafiltration membrane of the ceramic. However, in the supernatant process, the microporous substances which have not been separated by solid-liquid separation in the sedimentation tank 11 are piled up or adsorbed in the ceramic ultrafiltration membrane, . In addition, since the pollutants in the pores can not be easily removed by physical cleaning after the operation, the flux recovery rate is low.

Table 2 shows the difference in removal efficiency according to the operating conditions.

Membrane type Operation type COD removal efficiency (%) TOC removal efficiency (%) UF 50kDa
Rapid mixing 81.3 84.6 Supernatant 83.5 85.7 UF 150kDa
Rapid mixing 82.0 84.7 Supernatant 83.5 85.8

Table 2 shows the difference between the operating conditions and the COD and TOC removal efficiency of the membrane per membrane. The difference of the removal efficiency according to the operating conditions and the pore size was small.

In actual plant operation, when water is filtered through a ceramic ultrafiltration membrane after rapid mixing only, the area can be reduced because it does not include flocculation tank and sedimentation tank. At the same time, high flux can be maintained and removal of COD and TOC similar to the supernatant process Efficiency can be shown.

<Review>

The coagulated ceramic ultrafiltration process can be applied to the reuse of the wastewater, which accounts for most of the plating process. By applying this process, the process efficiency can be improved by reducing the membrane contamination of the ion exchange membrane and the reverse osmosis process.

Claims (13)

A step of neutralizing the alkaline plating water in the neutralization tank, a step of adding the coagulant in the mixing tank and mixing with the neutralized plating water, and a step of adjusting the pH of the plating solution to adjust the coagulation pH to the coagulant- A coagulation-bonding type ceramic ultrafiltration membrane process comprising a flocculation process and a ceramic filtration process including a step of charging and mixing;
Ion exchange process; And
The reverse osmosis filtration process is sequentially performed,
Wherein the ceramic filtration membrane process is carried out after the coagulation process without passing through another flocculation tank and a settling tank. delete delete The method according to claim 1, wherein the plating wastewater treated through the reverse osmosis filtration process is reused as plating wastewater. The method according to claim 1, wherein the coagulation-bonding type ceramic ultrafiltration membrane process Further comprising the step of removing the suspended material contained in the plating water with the microfilter. The method of claim 1, wherein the flocculation-type ceramic ultrafiltration membrane process separates flocks formed in the coagulation process in a ceramic filtration process. The method according to claim 1, wherein after plating the cohesive bond type ceramic ultrafiltration membrane, more than 80% of organic and colloidal materials are removed. The plating-treated water treatment method according to claim 1, wherein the plating water wash water to be treated includes a surfactant. The method according to claim 1, wherein the flocculation-type ceramic ultrafiltration membrane process has no separate flocculation tank and dirt tank diesel oil between the flocculation process and the ceramic filtration membrane process. A neutralization tank for neutralizing the alkaline plating water;
A mixing tank for rapidly mixing the neutralized plating water with the flocculant;
A pH adjusting tank which rapidly mixes with the pH adjusting solution to adjust the flocculation pH of the plating water discharged from the mixing tank;
A ceramic single surgical membrane separating the plating water discharged from the pH adjusting tank into water and fl ow without a coagulating bath and a settling tank for separate relaxation mixing;
Ion exchange membranes; And
Characterized in that the reverse osmosis filtration device is provided in the order of process. The plating water treatment apparatus according to claim 10, wherein a microfilter for removing suspended substances contained in the plating water is disposed in the neutralization tank transfer step. A wastewater treatment method characterized in that the following steps are sequentially carried out for wastewater containing an organic substance:
Neutralizing the alkaline wastewater in the neutralization tank; Admixing the coagulant in a mixing tank and mixing with neutral wastewater; And an agglomeration process comprising the step of injecting and mixing a pH adjusting solution to adjust the flocculation pH to the flocculated wastewater in the pH adjusting tank;
a ceramic filtration membrane process for treating wastewater discharged through the coagulation process without separately passing through a flocculation tank and a sedimentation tank requiring a lower mixing rate than a pH adjustment tank;
Ion exchange membrane process; And
Reverse Osmosis Filtration Membrane Process. 13. The method of claim 12, further comprising the step of removing suspended solids contained in the wastewater with a microfilter prior to the coagulation process.

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