CN106865860A - Energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit and method of wastewater treatment - Google Patents

Abstract

The invention discloses an energy recovery type wastewater catalytic wet oxidation treatment device. The wastewater storage tank and the catalyst storage tank are simultaneously connected to a first heat exchanger, the first heat exchanger is connected to a first reaction tower, and the first reaction tower is connected to a second heat exchanger. Heater, the second heat exchanger communicates with the second reaction tower, the outlet of the exchanged water of the second heat exchanger is connected with the turbine generator, the second reaction tower communicates with the first gas-liquid separator, and the gas phase of the first gas-liquid separator The outlet is connected to the first tail gas absorption tower, the liquid phase outlet is connected to the MVR evaporator, the MVR evaporator is connected to the third heat exchanger, the third heat exchanger is connected to the third reaction tower, and the third reaction tower is connected to the second gas-liquid separator , the gas phase outlet of the second gas-liquid separator is connected to the inlet of the second tail gas absorption tower; the air compressor provides reaction air for the first reaction tower, the second reaction tower and the third reaction tower. The invention has the advantages of being able to directly treat high-concentration and high-salt-content waste water, being environmentally friendly, low in cost, good in effect, small in floor space, and capable of recycling energy.

Description

Energy recovery type wastewater catalytic wet oxidation treatment device and wastewater treatment method

technical field

The invention relates to the technical field of industrial organic wastewater treatment, in particular to a device and method for treating industrial organic wastewater with high concentration and high salt content.

Background technique

Water pollution is an important problem that our country needs to address at present. To solve the problem of water pollution, we should first solve the source of pollution, that is, the generation and discharge of sewage, and industrial organic wastewater produced by factories is one of the main sources of water pollution. The pollutants in industrial wastewater have complex components, high biological toxicity, high COD, high salinity, dark color, and strong taste, so it is very difficult to deal with them. At present, the main treatment methods are: biological method, extraction method, incineration method, Fenton method and ozone method, etc., but the disadvantages of these methods are: (1) high treatment cost and poor treatment effect; (2) cannot directly deal with COD content For wastewater with a high salt content exceeding 100,000 mg/L, the COD content and salt content of the high-concentration and high-salt wastewater must be diluted and reduced before the high-salt wastewater is treated, and the treatment steps are complicated and cumbersome; (3) the applied The equipment occupies a large area; (4) There are secondary pollution to the environment and a large waste of energy in the process of wastewater treatment, which is not energy-saving and environmentally friendly.

Contents of the invention

The purpose of the present invention is to provide an energy recovery type wastewater catalytic wet oxidation treatment device and wastewater treatment device that can directly and efficiently treat high-concentration and high-salt organic wastewater, has no secondary pollution in the wastewater treatment process, and can effectively recycle and utilize energy method.

In order to achieve the above object, the present invention adopts the following technical solution: The energy recovery type wastewater catalytic wet oxidation treatment device includes a wastewater storage tank for storing wastewater, a catalyst storage tank for storing catalyst, and a pneumatic machine, the water outlet of the waste water storage tank and the outlet of the catalyst storage tank communicate with the inlet of the first heat exchanger at the same time, the outlet of the first heat exchanger communicates with the inlet of the first reaction tower, and the outlet of the first heat exchanger communicates with the inlet of the first reaction tower. The outlet of the first reaction tower communicates with the inlet of the second heat exchanger, the outlet of the second heat exchanger communicates with the inlet of the second reaction tower, and the outlet of the second heat exchanger is connected to the turbine Generator, the outlet of the second reaction tower communicates with the inlet of the first gas-liquid separator through the first heat exchanger, the gas phase outlet of the first gas-liquid separator communicates with the inlet of the first tail gas absorption tower, the second The liquid phase outlet of a gas-liquid separator is connected with the feed port of the MVR evaporator, the condensed water outlet of the MVR evaporator is connected with the feed port of the third heat exchanger, and the discharge port of the third heat exchanger is connected with the feed port of the third heat exchanger. The inlet of the third reaction tower is connected, the outlet of the third reaction tower is connected with the inlet of the second gas-liquid separator through the third heat exchanger, and the gas phase outlet of the second gas-liquid separator is connected with the inlet of the second tail gas absorption tower The air compressor provides reaction air for the first reaction tower, the second reaction tower and the third reaction tower through the pipeline.

Further, the aforementioned energy recovery type wastewater catalytic wet oxidation treatment device, wherein: the outlet of the second reaction tower is connected to the shell layer of the first heat exchanger, and the cold material and the hot material pass through the first heat exchanger in countercurrent, The shell outlet of the first heat exchanger communicates with the inlet of the first gas-liquid separator.

Further, the aforementioned energy recovery type wastewater catalytic wet oxidation treatment device, wherein: the outlet of the third reaction tower is connected to the shell layer of the third heat exchanger, and the cold material and the hot material pass through the third heat exchanger in countercurrent, The shell outlet of the third heat exchanger communicates with the inlet of the second gas-liquid separator.

Further, the aforementioned energy recovery type wastewater catalytic wet oxidation treatment device, wherein: the liquid phase outlet of the first gas-liquid separator is connected to the feed port of the first buffer tank, and the discharge port of the first buffer tank is connected to the The feed ports of the MVR evaporators are connected.

Further, the aforementioned energy recovery type waste water catalytic wet oxidation treatment device, wherein: the mother liquor evaporated from the MVR evaporator flows back to the catalyst storage tank.

A method for treating wastewater, comprising the steps of:

(1) Mix the homogeneous catalyst and waste water first and then heat up and pass it into the first reaction tower. The waste water mixed with the homogeneous catalyst and the reaction air provided by the air compressor in the first reaction tower are together in the first reaction tower. Carry out the first homogeneous catalytic wet oxidation reaction to generate primary treated water containing a homogeneous catalyst;

(2) Then pass the primary treatment water generated in step (1) into the second reaction tower after cooling down, and then make the primary treatment water and the reaction air provided by the air compressor in the second reaction tower together in the second reaction tower. The second homogeneous catalytic wet oxidation reaction is carried out in the tower to generate secondary treated water containing a homogeneous catalyst;

(3) Then cool down the secondary treated water generated in step (2) and pass it into the first gas-liquid separator for gas-liquid separation to generate a gas phase and a liquid phase containing a homogeneous catalyst;

(4) Then pass the liquid phase generated in step (3) into the MVR evaporator for evaporation to generate colorless crystalline salt, condensed water, and distilled mother liquor containing a homogeneous catalyst;

(5) Then heat up the condensed water generated in step (4) and pass it into the third reaction tower. The condensed water, the heterogeneous catalyst in the third reaction tower and the reaction air provided by the air compressor are together in the third reaction tower Carry out heterogeneous catalytic wet oxidation reaction to generate three-way treated water;

(6) Next, the temperature of the three treated water generated in step (5) is cooled and passed into the second gas-liquid separator for gas-liquid separation to generate a gas phase and a liquid phase that meets the emission standards.

The homogeneous catalyst is one or more of iron sulfate, iron nitrate, copper sulfate, copper nitrate, manganese sulfate, manganese nitrate, cobalt sulfate, cobalt nitrate, zinc sulfate, zinc nitrate, nickel sulfate, nickel nitrate.

The heterogeneous catalyst is a noble metal supported catalyst, and its carrier is one or more combinations of activated carbon, titanium dioxide, zirconium dioxide, aluminum oxide, silicon dioxide and molecular sieves, and its active components are ruthenium, rhodium , palladium, silver, platinum, cerium, lanthanum, neodymium in one or more.

Further, the aforementioned wastewater treatment method, wherein: the reaction conditions of the homogeneous catalytic wet oxidation reaction in step (1) are: the reaction temperature is (250~300) °C, the reaction pressure is (4.5~9) MPa, liquid The hourly space velocity is (0.5~3) h ^-1 , and the dosage of the homogeneous catalyst is (50~500) mg per liter of wastewater (calculated by the amount of metal ions).

Furthermore, the aforementioned wastewater treatment method, wherein: the reaction conditions of the homogeneous catalytic wet oxidation reaction in step (2) are: the reaction temperature is (220~290) °C, the reaction pressure is (2.5~8) MPa, liquid The hourly space velocity is (0.5~3) h ^-1 , and the dosage of the homogeneous catalyst is (50~500) mg per liter of wastewater (calculated by the amount of metal ions).

Furthermore, the aforementioned wastewater treatment method, wherein: the evaporation condition of the MVR evaporator in step (4) is: the evaporation temperature is (50-100) ° C, and the amount of the mother liquor after distillation is controlled in the liquid phase generated in step (3) (1~10)% of the amount.

Further, the aforementioned wastewater treatment method, wherein: the reaction conditions of the heterogeneous catalytic wet oxidation reaction in step (5) are: the reaction temperature is (180~280) °C, the reaction pressure is (2.0~7.5) MPa, liquid The hourly space velocity is (0.5~3) h ^-1 .

Through the implementation of the above technical solution, the advantages of the wastewater treatment device of the present invention are: (1) low treatment cost, good treatment effect, small footprint and high degree of automation; (2) without diluting wastewater, it can directly treat COD content exceeding 100,000 mg/L wastewater with high salt content; (3) There is no secondary pollution to the environment during the wastewater treatment process; (4) Recover excess heat through the heat exchanger, and use the steam generated by the heat exchanger Power generation by turbine generators achieves the purpose of energy recovery and utilization, and both realizes environmental benefits and obtains economic benefits; the advantages of the wastewater treatment method of the present invention are: good treatment efficiency, high COD removal rate, COD removal rate greater than 95.5%. There is no secondary pollution to the environment during the wastewater treatment process, and without diluting the wastewater, it can directly treat wastewater with a COD content of more than 100,000 mg/L and high salt content, especially for wastewater with volatile organic components. , MVR distilled mother liquor is reused to prepare a homogeneous catalyst, which not only solves the problem of concentrated liquid but also achieves the purpose of recycling, and the precipitated salt is colorless and clean salt, which can be recycled and reused.

Description of drawings

Fig. 1 is a schematic diagram of the structure and principle of an energy recovery type wastewater catalytic wet oxidation treatment device according to the present invention.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the described energy recovery type wastewater catalytic wet oxidation treatment device includes a wastewater storage tank 1 for storing wastewater, a catalyst storage tank 2 for storing catalysts, and an air compressor 3, the The water outlet of the waste water storage tank 1 communicates with the inlet of the pipeline mixer 6 through the first pipeline 5 provided with the first diaphragm pump 4, and the discharge port of the catalyst storage tank 2 communicates with the pipeline mixer 6 through the second pipeline 7 The inlet of the pipe mixer 6 is connected with the inlet of the first heat exchanger 9, and the outlet of the first heat exchanger 9 is connected with the inlet of the first reaction tower 10, and the top of the first reaction tower 10 The outlet of the second heat exchanger 11 communicates with the inlet of the second heat exchanger 11 through the fourth pipeline 12, and the outlet of the second heat exchanger 11 communicates with the inlet of the second reaction tower 13, and the heat exchange of the second heat exchanger 11 The water outlet is connected to the turbine generator 14, and the top outlet of the second reaction tower 13 communicates with the water exchange inlet of the first heat exchanger 9 through the fifth pipeline 15, and the water exchange outlet of the first heat exchanger 9 passes through The sixth pipeline 16 is communicated with the inlet of the first gas-liquid separator 17, so that the excess heat of the secondary treatment water generated by the second reaction tower 13 can be used for the high-concentration and high-salt organic matter passing through the first heat exchanger 9. The mixture of wastewater, homogeneous catalyst and air is heated to raise the temperature, thereby recovering heat and saving energy;

The gas phase outlet of the first gas-liquid separator 17 is communicated with the inlet of the first tail gas absorption tower 19 through the seventh pipeline 18, and the liquid phase outlet of the first gas-liquid separator 17 is connected with the first buffer tank through the eighth pipeline 20 21 is connected to the feed port, and the discharge port of the first buffer tank 21 is connected to the feed port of the MVR evaporator 24 through the ninth pipeline 23 provided with the second diaphragm pump 22, and the condensed water of the MVR evaporator 24 The outlet communicates with the inlet of the third heat exchanger 27 through the tenth pipeline 26 provided with the third diaphragm pump 25, and the outlet of the third heat exchanger 27 communicates with the inlet of the third reaction tower 28, The top outlet of the third reaction tower 28 communicates with the water exchange inlet of the third heat exchanger 27 through the eleventh pipeline 29, and the water exchange outlet of the third heat exchanger 27 communicates with the water exchange inlet of the third heat exchanger 27 through the twelfth pipeline 30. The inlets of the two gas-liquid separators 31 are connected, so that the excess heat of the three treatment waters generated by the third reaction tower 28 can be heated to raise the temperature of the condensed water passing through the third heat exchanger 27, thereby reclaiming heat and saving energy. energy;

The gas-phase outlet of the second gas-liquid separator 31 is communicated with the inlet of the second tail gas absorption tower 33 through the 13th pipeline 32, and the liquid-phase outlet of the second gas-liquid separator 31 is connected with the second gas-phase outlet through the 14th pipeline 34. The feed inlet of buffer tank 35 is communicated; Described air compressor 3 is communicated with the inlet of pipeline mixer 6 by the 3rd pipeline 8, thus provides reaction air for the first reaction tower 10, and passes through with the 4th pipeline The fifteenth pipeline 36 communicated with the road 12 provides reaction air for the second reaction tower 13, and simultaneously provides the reaction air for the third reaction tower 28 through the sixteenth pipeline 37 communicated with the tenth pipeline 26;

In this embodiment, the catalyst stored in the catalyst storage tank 2 is a homogeneous catalyst, and the homogeneous catalyst is iron sulfate, iron nitrate, copper sulfate, copper nitrate, manganese sulfate, manganese nitrate, cobalt sulfate, cobalt nitrate, One or more of zinc sulfate, zinc nitrate, nickel sulfate, and nickel nitrate can better treat high-concentration and high-salt organic wastewater after using the above-mentioned homogeneous catalyst, and the treatment effect is good;

In this embodiment, the third reaction tower 28 is filled with a multi-phase catalyst, the heterogeneous catalyst is a noble metal supported catalyst, and its carrier is activated carbon, titanium dioxide, zirconium dioxide, aluminum oxide, silicon dioxide molecular sieve One or more combination in, its active component is one or more in ruthenium, rhodium, palladium, silver, platinum, cerium, lanthanum, neodymium, after adopting above-mentioned heterogeneous catalyst, can be better to high concentration High-salt organic wastewater is treated, and the treatment effect is good;

The operating principle of the waste water treatment device of the present invention is as follows:

First pass the high-concentration and high-salt organic wastewater stored in the wastewater storage tank 1 into the pipeline mixer 6 through the first pipeline 5 through the first diaphragm pump 4, and simultaneously pass the homogeneous catalyst stored in the catalyst storage tank 2 through The second pipeline 7 is also passed into the pipeline mixer 6, and the air compressor 3 is also passed into the pipeline mixer 6 by the third pipeline 8 with the reaction air at the same time. and the air will enter the first heat exchanger 9 from the inlet of the first heat exchanger 9 after being mixed in the pipeline mixer 6, and then enter the first reaction tower 10 from the outlet of the first heat exchanger 9 Carry out sufficient homogeneous catalytic wet oxidation reaction in the middle, first reaction tower 10 can be discharged into the fourth pipeline 12 from the top outlet of the first reaction tower 10 with the primary treatment water formed after the reaction, and then from the fourth pipeline 12 Enter the feed port of the second heat exchanger 11, and now the air compressor 3 will also pass the reaction air into the feed port of the second heat exchanger 11 through the fifteenth pipeline 36, and the first reaction tower 10 comes out The primary treatment water will mix with the air in the second heat exchanger 11, and fully exchange heat with the water in the second heat exchanger 11, and the water in the second heat exchanger 11 will become The steam is supplied to the turbine generator to generate electricity, and the secondary treated water is discharged into the second reaction tower 13 after being cooled by heat exchange to carry out the second homogeneous catalytic wet oxidation reaction. The treated water is discharged into the fifth pipeline 15 from the top outlet of the second reaction tower 13, then enters the first heat exchanger 9 from the heat exchange water inlet of the first heat exchanger 9, and then flows from the first heat exchanger 9 The outlet of the exchanged water is discharged into the sixth pipeline 16. When the secondary treated water discharged from the second reaction tower 13 passes through the first heat exchanger 9, the waste heat of the secondary treated water will be passed through the first heat exchanger. 9’s high-concentration and high-salt organic wastewater, homogeneous catalyst and air are absorbed, so as to heat up the mixture of high-concentration and high-salt organic wastewater, homogeneous catalyst and air passing through the first heat exchanger 9, and After exchanging heat, it will gradually cool down;

At this time, the cooled secondary treated water in the sixth pipeline 16 will enter the first gas-liquid separator 17 for gas-liquid separation, and the first gas-liquid separator 17 will separate the secondary treated water into the gas phase It is discharged into the first tail gas absorption tower 19 through the seventh pipeline 18, and is discharged after being treated up to the standard through the first tail gas absorption tower 19, and the first gas-liquid separator 17 separates the liquid phase generated after the two-way treated water gas-liquid separation. Enter the first buffer tank 21 through the eighth pipeline 20, and then be pumped into the MVR evaporator 24 by the second diaphragm pump 22 through the ninth pipeline 23 for treatment. Among them, the mother liquor after distillation can be used for recycling to prepare a homogeneous catalyst, and the condensed water is pumped into the feed port of the third heat exchanger 27 by the third diaphragm pump 25 through the tenth pipeline 26. At this time, the air compressor 3 will convert the reaction Air is also passed into the feed port of the third heat exchanger 27 through the sixteenth pipeline 37, and the condensed water can be mixed with air in the third heat exchanger 27 and passed from the discharge port of the third heat exchanger 27 into the third reaction tower 28, and carry out sufficient heterogeneous catalytic wet oxidation reaction together with the heterogeneous catalyst in the third reaction tower 28, the third reaction tower 28 will discharge the three-way treatment water formed after the reaction from the top outlet into the eleventh pipeline 29, then enter the third heat exchanger 27 from the inlet of the third heat exchanger 27, and then discharge into the twelfth pipeline from the outlet of the third heat exchanger 27 30. When the three-pass treated water formed after the catalytic wet oxidation reaction discharged from the third reaction tower 28 passes through the third heat exchanger 27, the waste heat of the three-pass treated water will be condensed by the third heat exchanger 27 absorbed by water and air, so as to heat up the condensed water and air passing through the third heat exchanger 27, and gradually cool down after the heat exchange itself; The heat exchange port of 27 is discharged into the twelfth pipeline 30, and then enters the second gas-liquid separator 31 from the twelfth pipeline 30, and the second gas-liquid separator 31 performs gas-liquid separation of the three treatment waters to generate a gas phase and the liquid phase, the generated gas phase will be discharged into the second tail gas absorption tower 33 through the thirteenth pipeline 32 for up-to-standard treatment, and the generated liquid phase will enter the second buffer tank 21 through the fourteenth pipeline 34 , and then directly discharged from the second buffer tank 21 into the outside world or into the biochemical system for treatment. Through the above operations, the treatment of high-concentration and high-salt organic wastewater is completed.

The advantages of the wastewater treatment device of the present invention are: (1) low treatment cost, good treatment effect, small floor space and high degree of automation; Salt wastewater; (3) There is no secondary pollution to the environment in the wastewater treatment process; (4) Recover excess heat through the heat exchanger, and use the steam generated by the heat exchanger for the turbine generator to generate electricity, The purpose of energy recovery is achieved.

A method for treating wastewater, comprising the steps of:

(1) Treat a kind of organic intermediate production wastewater, the wastewater mainly contains 1,3-cyclohexanedione, sodium chloride and other components, COD is 125360 mg/L, pH=3.5, salinity is 12.5%; After the homogeneous catalyst is mixed with wastewater, the temperature is raised and passed into the first reaction tower. The wastewater mixed with the homogeneous catalyst and the reaction air provided by the air compressor in the first reaction tower are used for the first homogenization in the first reaction tower. Phase catalyzed wet oxidation reaction to generate primary treated water containing homogeneous catalyst; the reaction conditions of homogeneous catalyzed wet oxidation reaction are: reaction temperature is (250~300) ℃, reaction pressure is (4.5~9) MPa, liquid The hourly space velocity is (0.5~3) h ^-1 , and the dosage of the homogeneous catalyst is (50~500) mg per liter of wastewater;

(2) Then pass the primary treatment water generated in step (1) into the second reaction tower after cooling down, and then make the primary treatment water and the reaction air provided by the air compressor in the second reaction tower together in the second reaction tower. The second homogeneous catalytic wet oxidation reaction is carried out in the tower to generate secondary treated water containing a homogeneous catalyst. The reaction conditions of the homogeneous catalytic wet oxidation reaction are: the reaction temperature is (220~290) °C, and the reaction pressure is ( 2.5~8) MPa, the liquid hourly space velocity is (0.5~3) h ^-1 , and the dosage of the homogeneous catalyst is (50~500) mg per liter of wastewater;

(3) Then cool down the secondary treated water generated in step (2) and pass it into the first gas-liquid separator for gas-liquid separation to generate a gas phase and a liquid phase containing a homogeneous catalyst;

(4) Next, pass the liquid phase generated in step (3) into the MVR evaporator for evaporation to generate colorless crystalline salt, condensed water, and distilled mother liquor containing a homogeneous catalyst. The evaporation conditions of the MVR evaporator are: evaporation temperature (50~100)°C, the amount of distilled mother liquor is controlled at (1~10)% of the liquid phase generated in step (3);

(5) Then heat up the condensed water generated in step (4) and pass it into the third reaction tower. The condensed water, the heterogeneous catalyst in the third reaction tower and the reaction air provided by the air compressor are together in the third reaction tower Carry out heterogeneous catalytic wet oxidation reaction to generate three treated water. The reaction conditions of heterogeneous catalytic wet oxidation reaction are: reaction temperature is (180~280) ℃, reaction pressure is (2.0~7.5) MPa, liquid hourly space velocity is (0.5~3) h ^-1 ;

(6) Next, the temperature of the three treated water generated in step (5) is cooled and passed into the second gas-liquid separator for gas-liquid separation to generate a gas phase and a liquid phase that meets the emission standards.

The homogeneous catalyst is one or more of iron sulfate, iron nitrate, copper sulfate, copper nitrate, manganese sulfate, manganese nitrate, cobalt sulfate, cobalt nitrate, zinc sulfate, zinc nitrate, nickel sulfate, nickel nitrate.

The heterogeneous catalyst is a noble metal supported catalyst, and its carrier is one or more combinations of activated carbon, titanium dioxide, zirconium dioxide, aluminum oxide, silicon dioxide and molecular sieves, and its active components are ruthenium, rhodium , palladium, silver, platinum, cerium, lanthanum, neodymium in one or more.

The following table shows the COD, COD removal rate, salt content and PH value in the treated water obtained after two homogeneous catalytic wet oxidation reactions and heterogeneous catalytic wet oxidation reactions. The treatment effect of the wastewater treatment method is good.

The advantages of the wastewater treatment method of the present invention are: good treatment efficiency, high COD removal rate, the COD removal rate is greater than 95%, there is no secondary pollution to the environment during the wastewater treatment process, and the COD content can be directly treated without diluting the wastewater Wastewater with a high salt content exceeding 100,000 mg/L is especially advantageous for treating waste water with volatile organic components. MVR distilled mother liquor is reused to prepare a homogeneous catalyst, which not only solves the problem of concentrated liquid but also achieves the purpose of recycling , and the precipitated salt is colorless clean salt, which can be recycled and reused.

Claims (10)

1. energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit, it is characterised in that：Waste water storage including being used to store waste water Groove, it is used to store the catalyst carrier and air compressor machine of catalyst, the delivery port of the waste water storage tank and going out for catalyst carrier Material mouth is communicated with the charging aperture of First Heat Exchanger simultaneously, and the discharging opening of First Heat Exchanger is communicated with the import of the first reaction tower, the The outlet of one reaction tower is communicated with the charging aperture of the second heat exchanger, the import phase of the discharging opening of the second heat exchanger and the second reaction tower It is logical, the heat exchange water out connection turbine generators of second heat exchanger, the outlet of second reaction tower is through First Heat Exchanger Import with the first gas-liquid separator is connected, the import phase of the gaseous phase outlet of the first gas-liquid separator and the first tail gas absorber Connection, the liquid-phase outlet of the first gas-liquid separator is connected with the charging aperture of MVR evaporators, the condensation-water drain of MVR evaporators Charging aperture with the 3rd heat exchanger is connected, and the discharging opening of the 3rd heat exchanger is connected with the import of the 3rd reaction tower, and the 3rd is anti- Answer the outlet of tower to be connected with the import of the second gas-liquid separator through the 3rd heat exchanger, the gaseous phase outlet of the second gas-liquid separator with The import of the second tail gas absorber is connected；The air compressor machine is simultaneously the first reaction tower by pipeline, the second reaction tower and the Three reaction towers carry available for reaction air.

2. energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit according to claim 1, it is characterised in that：Second is anti- The outlet of tower is answered to be connected with the shell of First Heat Exchanger, with thermal material adverse current by First Heat Exchanger, first exchanges heat cold material The shell outlet of device is connected with the import of the first gas-liquid separator.

3. energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit according to claim 1, it is characterised in that：3rd is anti- The outlet of tower is answered to be connected with the shell of the 3rd heat exchanger, cold material is with thermal material adverse current by the 3rd heat exchanger, the 3rd heat exchange The shell outlet of device is connected with the import of the second gas-liquid separator.

4. energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit according to claim 1, it is characterised in that：First gas The liquid-phase outlet of liquid/gas separator is connected with the charging aperture of the first dashpot, discharging opening and the MVR evaporators of the first dashpot Charging aperture is connected.

5. energy recovery type Catalytic Wet Air Oxidation for Wastewater processing unit according to claim 1, it is characterised in that：MVR steams Mother liquor reflux is sent out more than the steaming of device to catalyst carrier.

6. a kind of method of wastewater treatment, it is characterised in that：Using the device as described in any one of Claims 1 to 5, and including such as Lower step：

（1）Heated up again after first homogeneous catalyst is mixed with waste water and be passed through the first reaction tower, be mixed with homogeneous catalyst waste water and The reaction provided by air compressor machine in first reaction tower carries out first time homogeneous catalysis wet type in the first reaction tower together with air Oxidation reaction, first road treatment water of the generation comprising homogeneous catalyst；

（2）Then by step（1）The second reaction tower is passed through after the first road treatment water cooling of generation, then Shi Chu roads treatment water and the The reaction provided by air compressor machine in two reaction towers carries out second homogeneous catalysis wet type oxygen with air in the second reaction tower together Change reaction, two roads treatment water of the generation comprising homogeneous catalyst；

（3）Then by step（2）Being passed through the first gas-liquid separator after the two roads treatment water cooling of generation carries out gas-liquid separation, generates Gas phase and the liquid phase containing homogeneous catalyst；

（4）Then by step（3）The liquid phase of generation is passed through MVR evaporators and is evaporated, and generates colourless crystallization salt, condensed water and contains There is mother liquor more than the steaming of homogeneous catalyst；

（5）Then by step（4）The condensed water of generation is passed through the 3rd reaction tower, multiphase in condensed water and the 3rd reaction tower after heating up Catalyst and by air compressor machine provide reaction carry out heterogeneous catalysis wet oxidation reaction in the 3rd reaction tower together with air, Generate three roads treatment water；

（6）Then by step（5）Being passed through the second gas-liquid separator after the three roads treatment water cooling of generation carries out gas-liquid separation, generates Gas phase and meet the liquid phase of discharge standard；

Described homogeneous catalyst is ferric sulfate, ferric nitrate, copper sulphate, copper nitrate, manganese sulfate, manganese nitrate, cobaltous sulfate, nitric acid One or more in cobalt, zinc sulfate, zinc nitrate, nickel sulfate, nickel nitrate；

Described heterogeneous catalyst is noble metal carrier catalyst, and its carrier is activated carbon, titanium dioxide, zirconium dioxide, three One or more in Al 2 O, silica and molecular sieve combination, its active component be ruthenium, rhodium, palladium, silver, platinum, cerium, lanthanum, One or more in neodymium.

7. a kind of method of wastewater treatment according to claim 6, it is characterised in that：Step（1）Middle homogeneous catalysis wet type oxygen Changing the reaction condition for reacting is：Reaction temperature is（250~300）DEG C, reaction pressure is（4.5~9）MPa, liquid hourly space velocity (LHSV) is（0.5 ~3） h^-1, the dosage of wherein homogeneous catalyst is that every liter of waste water is added（50~500）mg.

8. a kind of method of wastewater treatment according to claim 6, it is characterised in that：Step（2）Middle homogeneous catalysis wet type oxygen Changing the reaction condition for reacting is：Reaction temperature is（220~290）DEG C, reaction pressure is（2.5~8）MPa, liquid hourly space velocity (LHSV) is（0.5 ~3） h^-1, the dosage of wherein homogeneous catalyst is that every liter of waste water is added（50~500）mg.

9. a kind of method of wastewater treatment according to claim 6, it is characterised in that：Step（4）The evaporation of middle MVR evaporators Condition is：Evaporating temperature is（50~100）DEG C, remaining mother liquor amount control is steamed in step（3）The amount of liquid phase of generation（1~10）%.

10. a kind of method of wastewater treatment according to claim 6, it is characterised in that：Step（5）Middle heterogeneous catalysis wet type oxygen Changing the reaction condition for reacting is：Reaction temperature is（180~280）DEG C, reaction pressure is（2.0~7.5）MPa, liquid hourly space velocity (LHSV) is （0.5~3） h^-1。