WO2010066181A1

WO2010066181A1 - Simple method and system for recycling mother liquor of pta apparatus efficiently

Info

Publication number: WO2010066181A1
Application number: PCT/CN2009/075352
Authority: WO
Inventors: 罗文德; 周华堂; 姚瑞奎; 张莼; 陈孟和; 李利军; 袁骏
Original assignee: 中国石油天然气集团公司; 中国纺织工业设计院
Priority date: 2008-12-08
Filing date: 2009-12-07
Publication date: 2010-06-17
Also published as: CN101417943A; RU2471767C1; CN101417943B

Abstract

Disclosed is a simple method for recycling the refinement mother liquor of PTA apparatus efficiently and a system used in the method. The method comprises the following steps: (1) the refinement mother liquor is cooled by heat exchange method; (2) the cooled refinement mother liquor is processed by ultrafiltration, and the ultrafiltration concentrated solution is returned to oxidation unit; (3) the ultrafiltration filtrate is processed by ion exchanging; at first, Co and Mn ions in the filtrate are selectively adsorbed, and Co and Mn desorption liquid is recycled as catalyst, then other metal ions are adsorbed; and (4) the liquid after ion exchanging is used as the endothermic medium of step (1) to heat exchange with the refinement mother liquor, and after warming, a small part is emitted, and the majority is transmitted to a drying spray tower for spraying. The system comprises a heat exchange system, an ultrafiltration system, an ion exchanging system and a drying spray tower. The method has the following advantage: the treating process is greatly simplified; the investment cost and operation cost are reduced; the energy consumption is lowered; the method is benefited to environment protection and energy saving; and the economic benefit is also increased.

Description

Efficient recycling and utilization of PTA device for the purification of mother liquor and its technical field

The invention relates to a simple method for efficiently recycling a mother liquor by using a PTA device and a recycling system using the same method, and belongs to the technical field of chemical industry and environmental protection.

Background technique

The refining unit of the PTA (fine terephthalic acid) device uses water as a solvent to dissolve the crude terephthalic acid (CTA) by heating and then enters the refining reactor. In the presence of the catalyst, hydrogen (H ₂ ) is used. The main impurity in the slurry is reduced to carboxybenzaldehyde (4-CBA) to water-soluble p-nonylbenzoic acid (p-TA), and then processed by crystallization, filtration or centrifugation, drying, etc. The product is refined with p-benzoic acid (PTA). In the TA filtration or centrifugation process, a large amount of aqueous solution (refined mother liquor) is contained, which contains TA, p-TA, HAC and a small amount of catalyst (ca t ), 4-CBA and other metal ions, the conventional PTA device The refined mother liquor is directly discharged into the sewage treatment plant, and the useful components and water are not recovered. As a result, the material consumption and energy consumption of the device are high, and the sewage treatment is difficult.

With the development of society, people's awareness of environmental protection has increased. At the same time, in order to reduce costs and improve product competitiveness, enterprises urgently need to reduce material consumption and reduce energy consumption. In recent years, most of the PTA plants have been equipped with a refined mother liquor recovery facility, and various filters have been used to recycle TA and p-TA in the mother liquor to reduce product consumption and reduce sewage treatment pressure. Although these recycling facilities have certain effectiveness, the recovery of useful components is incomplete, and the plant still has a large amount of sewage effluent containing more TA, p-TA and other impurities, which pollutes the environment.

In order to improve the recovery of useful components and water in the refined mother liquor, China 20071 0044416. No. 3 invention patent application discloses a comprehensive treatment and utilization method of PTA purified wastewater, which can be combined with the original PTA production device and PTA recovery. The system includes the following steps: (A) After cooling the PTA refined wastewater to a temperature lower than 60 degrees, the first membrane separation device is introduced for separation, and the retained concentrated liquid is introduced. Return the gTA to the original PTA recovery system, and filter the filtrate into the B step; (B) introduce the filtrate from step (A) into the secondary membrane separation unit for separation, and the trapped concentrate enters (D) step, filter The liquid is directly reused, or enters (C) step treatment; (C) the filtrate obtained in step B is introduced into the water recovery ion exchange system, and further removes trace ions to meet the water quality requirements of deionized water, and is reused as process water for production. (D) The concentrated liquid obtained in the step (B) is pretreated and introduced into a catalyst recovery ion exchange system to adsorb cobalt manganese ions, and after adsorption saturation, a high concentration cobalt manganese solution is obtained, and the cobalt manganese catalyst is recovered. The first membrane separation device adopts a stainless steel membrane or a ceramic membrane or a submerged membrane group, and the filtration pore diameter of the membrane is selected from the range of 10 to 1 000; and the secondary membrane separation device uses a polymer membrane, The magnesium sulfate rejection rate is above 90%; the polymer membrane is a reverse osmosis membrane or a nanofiltration membrane; the water recovery ion exchange system comprises a cation exchange column and an anion exchange column, and the flow rate of the ion exchange column is controlled at 1 - 8BV; The catalyst recovery ion exchange system uses a chelating resin or a strong acid resin or a cationic resin to adsorb cobalt manganese, and the resin is saturated and then eluted and regenerated with an acid. This patent application greatly improves the recovery rate of TA, p-TA, cobalt, manganese and water in the refined mother liquor, and the water purification degree after treatment is relatively high, and the recycling range is wide, but it is used more The membrane separation technology, especially the second membrane treatment, uses high-energy treatment such as reverse osmosis, so the power consumption is large, the equipment is complicated, the investment is large, and the running cost is high, which affects the actual situation, especially in the power shortage area. Promote the application.

Summary of the invention

In order to overcome the above-mentioned drawbacks of the prior art, the present invention provides a simple method for efficiently recycling a mother liquor by using a PTA device, and also provides a specific implementation process for efficiently recycling a mother liquor using the PTA device by using the method. It satisfies the high-efficiency recycling of the useful components in the refined mother liquor, greatly simplifies the treatment process, reduces the complexity of the system, and especially eliminates the high energy-consuming steps such as reverse osmosis in the prior art, and reduces the investment cost and operation. Cost, not only environmental protection and energy saving, but also High economic efficiency.

The technical solution of the present invention to achieve the above object is:

An easy way to efficiently recycle the mother liquor from the PTA unit, including the following steps:

(1) using a heat exchange method to cool the refined mother liquor;

(2) treating the refined mother liquor after cooling by ultrafiltration, and recycling the ultrafiltration concentrate to the oxidation unit;

(3) performing ion exchange treatment on the ultrafiltration filtrate, first selecting Co and Mn ions in the adsorption filtrate, and reusing the Co and Mn desorption liquid to reuse the catalyst, and then adsorbing other metal ions;

(4) After the separation, the liquid is used as the heat absorption medium of step (1) to exchange heat with the refined mother liquor. After the heat exchange, most of the liquid is sent to the dryer spray tower, according to the spray demand and refining of the spray tower of the dryer. The material balance of the unit, the excess part is discharged, and the liquid sprayed by the spray tower of the dryer is returned to the refining system.

In the step (1), the refined mother liquid is cooled in two steps. The first step is to use the step (4) to transfer the liquid as the heat absorption medium for heat exchange, to lower the temperature of the refined mother liquid, and the second step is to cool. The refined mother liquor is further cooled by wind or cooling water so that the temperature of the refined mother liquor satisfies the subsequent ultrafiltration requirements. Usually, after the heat exchange in the first step of step (1), the temperature of the refined mother liquor can be lowered to 72 ~ 77 °C, or about 74 °C, after the second heat exchange (cooling), the temperature of the refined mother liquor It is 40 ~ 45 °C.

In the step (2), the sintered metal coated T i0 ₂ membrane filter material is preferably used, and the filtration precision is 50-100 nm, and the filtration method is concentrated by cross-flow, and the discharged concentrate has a solid content of 15-20%.

In the step (3), the ion exchange is carried out in two steps, and the first step uses ion exchange resin capable of selectively adsorbing Co and Mn ions, and then the broad spectrum absorption of the liquid helium after the first step is separated. The metal ion ion exchange resin adsorbs the remaining various metal ions, including Fe, Ni, Na ions, and the first step of ion exchange, using HBr as an eluent to elute and regenerate the ion exchange resin, and the resulting Co and Mn are desorbed. The liquid can be sent to the oxidation unit for use as a catalyst, and the second step is ion exchanged with HC 1 as a wash. The ion exchange resin is eluted and regenerated by deliquoring, and the resulting desorbed liquid containing Fe, Ni, Na ions can be sent to a sewage treatment system for purification treatment.

In the step (4), the post-dissociation liquid of the step (3) is sent to the heat exchange system of the first step in the step (1) as a heat absorption medium, and the temperature of the post-dissociation liquid after the endothermic heat is generally It should be around 72 °C (for example, 70 ~ 75 °C).

After the separation liquid heated by the step (4), a small amount of excess portion should be discharged according to the material balance of the subsequent recycling system, and most of the liquid is sent to the dryer spray tower as a spray liquid, and then the spray is separated. The post-liquid is sent to the refining system for use.

A simple system for efficiently recycling a mother liquor by using a PTA apparatus, comprising a heat exchange system, an ultrafiltration system, an ion exchange system, and a dryer spray tower, the heat exchange system including a first heat exchanger and a cooling device, the ion The exchange system includes a first ion exchange unit and a second ion exchange unit, the heat release medium outlet of the first heat exchanger is connected to the heat release medium inlet of the cooling device, and the heat release medium outlet of the cooling device is connected to the ultrafiltration An inlet of the system, an ultrafiltration filtrate outlet of the ultrafiltration system is connected to an inlet of the first ion exchange unit, an outlet of the first ion exchange unit is connected to an inlet of the second ion exchange unit, and the second ion exchange unit The outlet is connected to the heat absorption medium inlet of the first heat exchanger, and the heat absorption medium outlet of the first heat exchanger is connected to the spray pipe of the dryer spray tower.

The heat-releasing medium inlet of the first heat exchanger is connected to the refined mother liquid pipeline, and the heat-absorbing medium inlet and the heat-absorbing medium outlet of the cooling device can be connected to a cooling air duct or a cooling water pipeline, and the ultrafiltration system is ultrafiltered. The concentrate outlet is connected to the oxidation reactor feed line of the oxidation unit, the desorption liquid outlet of the first ion exchange unit is connected to the oxidation reactor feed line of the oxidation unit, and the desorption liquid outlet of the second ion exchange unit A sewage treatment system is connected, and the spray liquid discharge port of the dryer spray tower can be connected to the recirculating solvent pipeline of the refining system.

The ultrafiltration system preferably has a cross-flow concentration structure and is provided with a plurality of circulation pumps for cross-flow concentration. The filter material is preferably a sintered metal coated Ti0 ₂ film structure filter material, and the filtration precision is 50 - 100 nm.

The ultrafiltration system may be provided with an ultrafiltration concentrate tank, and the ultrafiltration concentrate tank is provided with a stirrer. The ultrafiltration system may also be provided with an ultrafiltration filtrate tank.

A heater may be provided on the connecting pipe between the ultrafiltration filtrate outlet of the ultrafiltration system and the inlet of the first ion exchange unit, and the heater is preferably a low pressure steam heater.

The ion exchange system is preferably a continuous ion exchange system, the first ion exchange unit is an ion exchange unit capable of selectively adsorbing Co, Mn ions, and the second ion exchange unit is capable of broadly adsorbing Fe, Ni, Na, etc. A metal ion ion exchange unit, the first ion exchange unit may be provided with a desorption liquid tank.

The first ion exchange unit and the second ion exchange unit are respectively provided with an input port for rinsing and regenerating liquid such as an HBr input port for ion exchange resin regeneration and an HC 1 input port.

The beneficial effects of the invention are: integration with the PTA production system, realizing the reuse of most of the water and other useful materials in the refined mother liquor, greatly reducing the pollutant discharge, saving the production cost of the PTA, especially According to the balance of various materials in the production process of PTA, the rational process of recycling, the process of refining the mother liquor is simplified without reducing the quality of PTA, and the excessive purification of the refined mother liquor is avoided, thereby greatly reducing The energy consumption in the refined mother liquor treatment reduces the processing cost of the refined mother liquor and improves the investment benefit of the refined mother liquor reuse. According to preliminary estimation, the investment recovery period is about 2 years, which is significantly lower than the prior art.

DRAWINGS

Figure 1 is a schematic diagram of the process of the present invention;

2 is a schematic view showing the system structure and process flow of the present invention.

Detailed ways

Referring to FIG. 1 and FIG. 2, the specific implementation of the present invention may be based on the above technical solutions, and will not be described again. The process of combining the features and main contents of the present invention is as follows:

The basic idea:

In the current PTA production technology, the main impurities of the refined mother liquor include: TA 0. 5 ~ 1%, p-TA ~ 0.2% and a small amount of HAC, 4CBA, Co ions, Mn ions and other metal ions. Among these impurities, TA, p-TA, Co ion, Mn ion, etc. are all useful materials in the production of PTA. Therefore, according to the specific requirements of the production process and the material balance in the production process, the refined mother liquor can be treated moderately. The materials that can be recycled, heavy metals and water are used in the step-by-step process for the relevant process units without the need to purify these useful materials and reuse the water.

Therefore, the present invention changes the prior art method for excessive purification of the refined mother liquor. According to the actual needs of the various processes of the PTA production process, the refined mother liquor is only subjected to a moderate treatment, and is sent when the treated refined mother liquor meets the requirements of the production process. The production system is reused. Because different production processes have different requirements for the reuse of the refined mother liquor, a reasonable and appropriate treatment step is selected in the process of the refined mother liquor, so that the different production can be stepped in the process of the refined mother liquor. The requirements of the process are continuously introduced into the production system, especially because the high-efficiency reverse osmosis treatment of the refined mother liquor is no longer carried out, which greatly reduces the energy consumption and treatment cost of the refined mother liquor treatment, and also greatly reduces the refined mother liquor. Processing investment.

According to the applicant's experiment, the solid content of the ultrafiltration concentrate fed to the oxidation unit is preferably 15 - 20%. Too low a solid content will have an adverse effect on PTA, while too high a solid content will increase significantly. The cost of large ultrafiltration; after the ion exchange, the proportion of the liquid after the separation to the refining system can be about 80% of the total amount of the liquid after the separation. The main impurity content in the ultrafiltration filtrate should generally be controlled at TA: 0. 01 - 0. 02 %, p-TA: 0. 07 - 0. 08 %, HAC: 0. 02 - 0. 03 %, 4CBA : 0. 0001 - 0. 0002 %, Co ion: 0. 0015 - 0. 002 %, Mn ion: 0. 0015 - 0. 002 %, Fe, Ni, Na Other metal ions: 0. 0005 - 0. 001 %; The main impurity content in the liquid after the separation should generally be controlled at TA: 0. 01 - 0. 02 %, p-TA: 0. 07 - 0. 08 %, HAC: 0. 02 - 0. 03 %, 4CBA: 0. 0001 - 0. 0002 %, Co ion: 0 0002 - 0. 0003 %, Mn ion: 0. 0002 - 0. 0003 %, Fe, Ni, Na Other metal ions: 0. 00005 - 0. 0001 %; After the first heat exchanger According to the water balance and material balance of the refining system, the proportion of the spray tower and the outer row (usually sent to the sewage treatment plant for sewage treatment) sent to the dryer should be determined. The amount of liquid after the departure of the general discharge can account for the departure. The total amount of post-liquid is about 15 - 25 %. Under the above parameters, the treatment and reuse methods of the present invention do not adversely affect PTA production and product quality.

According to the actual situation, it is also possible to provide a bypass pipe on the connecting pipe or the outlet of the processing device between the processing devices of the present invention, so as to take out the liquid to be treated and use it, and the utilization may adopt any suitable prior art or Other possible technologies.

Main technique:

The main treatment process of this patent is to recover TA and p-TA fine particles by ultrafiltration technology, and to recover Co ions, Mn ions and other metal ions by ion exchange technology, which will contain certain TA and p-TA components after treatment. The water is reused in a suitable production process, rather than using a further purification method to completely remove these impurities. The filter material in the ultrafiltration system is coated with Ti0 ₂ film with sintered metal, the precision is up to 50 ~ 100 nanometers (nm), and the filtration method is cross-flow concentration. The recovery rate of this filtration concentration method is higher, the solid content of the concentrate 15-20%, can be directly used in production systems, and operation is relatively easy. After the ultrafiltration filtrate, the catalyst cobalt (Co) and manganese (Mn) in the filtrate are selectively adsorbed by ion exchange resin, then desorbed with HBr aqueous solution, and the desorbed liquid (Ca t ) is returned to the production system for use. The filtrate after removal of Co and Mn metal is adsorbed by an ion resin to remove other metal ions (Fe, Ni, Na, etc.), and then the ultrafiltration filter after secondary ion exchange according to the demand of the production system. The amount of ~80% of the liquid is directly returned to the refining system for use, and the other ~20% amount determines the amount of the discharge according to the product quality and the system water balance, and the discharge liquid enters the sewage treatment plant. Main process flow:

The filtered wastewater (refined mother liquor) separated by the PTA unit refining unit is cooled to a design temperature by heat exchange and cooling, and then enters a stainless steel membrane ultrafiltration separation device, and is concentrated and filtered by a circulating pump. The stainless steel membrane separation device intercepts the TA and p-TA suspended solids which are crystallized in the wastewater, and the concentrated liquid formed by the retained suspended solids is collected in the ultrafiltration concentrate storage tank and pumped to the oxidation unit of the PTA unit for recycling. The stainless steel membrane separator filters out the supernatant and enters the filtrate tank, which is then pumped into the heater to slightly increase its temperature before entering the continuous ion exchange catalyst recovery system. The ion exchange resin first selectively adsorbs and concentrates the cobalt manganese ions, and after adsorption saturation, is analyzed by dilute HBr aqueous solution to obtain a cobalt manganese catalyst solution, and the analytical solution enters the catalyst tank, and is pumped to the oxidation system for reuse. The ion exchange resin effluent is again passed through the secondary ion exchange resin, adsorbed to other metal ions, and then desorbed with dilute hydrochloric acid, and the desorbed liquid is discharged into the sewage treatment. The liquid stream from which the metal ions are removed enters the liquid tank after the separation, and is sent out by the transfer pump. The heat is exchanged with the refined mother liquid of about 100 ° to increase the temperature to ~ 72 ° C, ~ 80 % of the liquid. The flow enters the dryer rinsing tower spray and returns to the refining system. According to the operation of the device and the water balance, ~20% of the liquid is discharged into the sewage treatment.

For the ultrafiltration membrane system, regular flushing and chemical cleaning, flushing and cleaning of wastewater discharge; periodic rinsing of the ion exchange system and regeneration of acid and alkali, and regeneration of wastewater.

Implementation example:

The temperature of the refined mother liquor after flashing is reduced to about 100 °C. The concentration of p-TA in the mother liquor is 2000 ~ 2500 PPM, and the TA content is about 0.5 to 1. 0% Wt. Liquid heat exchange, the temperature is reduced to ~ 72 °C, and then cooled by circulating cooling water through the cooler, the mother liquid is cooled to 40 ~ 45 °C, at this time, about 65% of the P-TA in the mother liquor is precipitated, and the TA is basically precipitated. 6〜 1. 0%Wt。 (95% or more), the mother liquid solid content is about 0. 6 ~ 1. 0% Wt. After cooling, the mother liquor is pumped into the stainless steel membrane ultrafiltration system through the mother liquor tank, and is circulated and filtered by a circulation pump to concentrate and concentrate to a solid content of 16 to 18% of Wt. The concentrate is withdrawn and discharged to the belt. The concentrate tank is then pumped to the oxidation unit for recycling. The ultrafiltration system filtrate enters the filtrate tank and is pumped to the heater for heating with low pressure steam, which is heated to about 45 °C into the first ion exchange unit of the continuous ion exchange catalyst recovery system, through the ion exchange resin. The cobalt manganese metal ions are selectively adsorbed first, and the saturated resin is desorbed with an aqueous solution of HBr, and the analytical solution is pumped back to the oxidation system through the catalyst tank for recycling. After the removal of Co and Mn ions, the stream enters the secondary ion resin exchange column (second ion exchange unit), adsorbs to other metal ions, and is desorbed with dilute hydrochloric acid, and the metal ion-containing desorption liquid is discharged to the sewage treatment. After the separation, the liquid is pumped out, sent to the heat exchanger for heat exchange with the refined mother liquor after the flashing of 100'C, and the temperature is raised to 70-75 ° C, and 80% is sent to the dryer rinsing tower. Return to the refining system, and the remaining 20% is discharged to the sewage treatment.

The ultrafiltration and ion exchange systems all have backwashing facilities. They are regularly cleaned with acid, alkali and demineralized water, and the washing liquid is discharged to the sewage treatment.

Claims

Claim

1. A simple method for efficient recycling of the mother liquor from the PTA unit, which is characterized by the following steps:

(1) using a heat exchange method to cool the refined mother liquor;

(4) After the separation, the liquid is used as the heat absorption medium of step (1) to exchange heat with the refined mother liquor. After the heat exchange, most of the liquid is sent to the spray tower of the dryer for discharge, and the spray tower of the dryer is sprayed. The liquid is reused for the refining system.

2. The method for efficiently purifying a mother liquor by using a PTA apparatus according to claim 1, wherein in the step (1), the refined mother liquor is cooled in two steps, and the first step is to use the step (4). The post-exchange liquid is heat exchanged as a heat absorption medium to lower the temperature of the refined mother liquid. The second step is to further cool the refined mother liquid by cooling air or cooling water, so that the temperature of the refined mother liquid satisfies the subsequent ultrafiltration requirements.

3. The method for efficiently purifying a mother liquor by using a PTA apparatus according to claim 1, wherein after the heat exchange in the first step of the step (1), the temperature of the liquid after the separation increases to 70 to 75 °C. The temperature of the refined mother liquor is 72 ~ 77 °C. After the second heat exchange, the temperature of the refined mother liquor is 40 ~ 45 °C.

4. The method for efficiently purifying a mother liquor by using a PTA apparatus according to claim 1, 2 or 3, wherein in the step (2), a sintered metal coated T i 0 ₂ membrane filter material is used, and the filtration precision is used. It is 50 ~ 100 nm, and the filtration method is concentrated by cross-flow, and the discharged concentrate has a solid content of 15-20%.

5. The method for efficiently recycling a mother liquor of the PTA apparatus according to claim 4, wherein The method is characterized in that in the step (3), the ion exchange is carried out in two steps, and in the first step, the ion exchange resin capable of selectively adsorbing the Co and Mn ions is ion-exchanged, and then the liquid is used for the first step after the separation. The ion exchange resin that absorbs metal ions absorbs the remaining various metal ions, and the first step is used for ion exchange.

The ion exchange resin was eluted and regenerated by HBr as an eluent. The second step of ion exchange was carried out by eluting the ion exchange resin with HC1 as an eluent.

6. A simple system for efficiently recycling a mother liquor from a PTA apparatus, comprising a heat exchange system, an ultrafiltration system, an ion exchange system, and a dryer spray tower, the heat exchange system including a first heat exchanger and cooling The apparatus, the ion exchange system includes a first ion exchange unit and a second ion exchange unit, the exothermic medium outlet of the first heat exchanger is connected to an exothermic medium inlet of the cooling device, and the exothermic medium outlet of the cooling device Connecting an inlet of the ultrafiltration system, an ultrafiltration filtrate outlet of the ultrafiltration system is connected to an inlet of the first ion exchange unit, and an outlet of the first ion exchange unit is connected to an inlet of the second ion exchange unit, The outlet of the second ion exchange unit is connected to the heat absorption medium inlet of the first heat exchanger, and the heat absorption medium outlet of the first heat exchanger is connected to the spray pipe of the dryer spray tower.

7. The simple system for efficiently recycling a mother liquor of a PTA apparatus according to claim 6, wherein the heat medium inlet of the first heat exchanger is connected to a refined mother liquor pipeline, and the heat absorption medium inlet of the cooling device is The heat absorbing medium outlet is connected to the cooling air duct or the cooling water pipeline, the ultrafiltration concentrate outlet of the ultrafiltration system is connected to the oxidation reactor feed pipe of the oxidation unit, and the desorption liquid outlet of the first ion exchange unit is connected and oxidized An oxidation reactor feed line of the unit, a desorption liquid outlet of the second ion exchange unit is connected to the sewage treatment system, and the second ion exchange unit outlet and the first heat exchanger heat absorption medium outlet pipe are connected and refined. The dryer of the system washes the tower spray pipe, the second ion exchange unit outlet and the first heat exchanger heat absorption medium outlet pipe are connected to the sewage treatment system, and the spray liquid discharge of the dryer spray tower The mouth is connected to the refining system to recycle the solvent line.

8. The simple system for efficiently recycling a mother liquor of a PTA apparatus according to claim 6 or 7, The ultrafiltration system is characterized in that the ultrafiltration system is preferably a cross-flow concentrating structure, and a plurality of circulating pumps for cross-flow concentration are provided, and the filter material used is preferably a sintered metal-coated Ti0 ₂ membrane structure filter material, and the filtration precision is 50 - 100. Nano.

9. The system for efficiently recycling a mother liquor of the PTA apparatus according to claim 8, wherein the ultrafiltration system is provided with an ultrafiltration concentrate tank and an ultrafiltration filtrate tank, and the ultrafiltration concentrate tank A stirrer is disposed therein, and a heater is disposed on the connecting pipe between the ultrafiltration filtrate outlet of the ultrafiltration system and the inlet of the first ion exchange unit, and the heater is a low pressure steam heater.

10. The simple system for efficiently recycling a mother liquor of a PTA apparatus according to claim 9, wherein the ion exchange system is a continuous ion exchange system, and the first ion exchange unit is an ion that selectively adsorbs Co and Mn ions. An exchange unit, wherein the second ion exchange unit is an ion exchange unit that broadly adsorbs various metal ions such as Fe, Ni, Na, and the first ion exchange unit is provided with a desorption liquid tank, and the first ion exchange unit The second ion exchange unit is provided with an input port for rinsing and regenerating liquid such as an HBr input port for ion exchange resin regeneration and an HC 1 input port.