Equipment and process for resource utilization of bisphenol A production wastewater

Abstract

The present invention discloses a resource utilization device and process for bisphenol A production wastewater, which includes a preheater, a first-stage falling film evaporator, a second-stage forced circulation evaporator, a crystallization and salt-out system, a steam recompression device, and a tail gas treatment system. The preheater includes a distilled water preheater and a secondary steam preheater, and the distilled water preheater and the secondary steam preheater are sequentially connected through pipelines. For the resource utilization device and process of bisphenol A production wastewater, components such as sodium sulfate and trace amounts of acetone and phenol contained in the bisphenol A wastewater can be discharged after being treated qualified. After being treated by the MVR device, the sodium sulfate crystallizes into salt as a by-product, the distilled water is recovered and used as makeup water for the circulating water device, valuable sodium sulfate salt is obtained, and condensable water that can be discharged is obtained; it has a simple structure, small floor area, low equipment investment, and realizes the automated production process of treating bisphenol A production wastewater and extracting valuable sodium sulfate, with high production efficiency and no environmental damage.

Description

Technical Field

[0001] The present invention relates to the technical field of resource utilization of bisphenol A production wastewater, and particularly to an apparatus and process for resource utilization of bisphenol A production wastewater. Background Art

[0002] Evaporation crystallization refers to the process of separating the solvent from the solute in a solution by heating, so that the solute polymerizes into a solid. Evaporation crystallization is widely used in evaporation equipment.

[0003] Bisphenol A is one of the most widely used industrial compounds in the world, mainly used in the production of various high molecular materials such as polycarbonate, epoxy resin, polysulfone resin, polyphenylene ether resin, and unsaturated polyester resin. It can also be used in the production of fine chemical products such as plasticizers, flame retardants, antioxidants, heat stabilizers, rubber antioxidants, pesticides, and coatings. The wastewater generated during its production is difficult to recycle due to the presence of organic salts and organic solvents.

[0004] Currently, the processes for treating bisphenol A production wastewater mostly adopt single-effect or multi-effect evaporation methods. During the concentration of bisphenol A wastewater, as the solution concentration increases, the boiling point and viscosity coefficient also increase accordingly. The traditional evaporation mode, the characteristics of single-effect or multi-effect evaporation processes are using fresh steam as the heat source and continuously utilizing secondary steam, which cannot balance the concentration crystallization effect and energy-saving requirements of bisphenol A wastewater, resulting in poor concentration effect and high production cost. Summary of the Invention

[0005] The present invention mainly solves the technical problems existing in the above-mentioned prior art, and provides an apparatus and process for resource utilization of bisphenol A production wastewater with low energy consumption and high automation efficiency.

[0006] To achieve the above object, the present invention provides the following technical solutions: An apparatus and process for resource utilization of bisphenol A production wastewater, comprising

[0007] A preheater, the preheater includes a distilled water preheater and a secondary steam preheater, and the distilled water preheater and the secondary steam preheater are sequentially connected through pipelines;

[0008] A first-stage falling-film evaporator, the first-stage falling-film evaporator includes a first-stage falling-film heat exchanger, a first falling-film circulation pump, a second falling-film circulation pump, a falling-film separator, and a first-stage transfer pump. The first-stage falling-film heat exchanger is connected to the first falling-film circulation pump and the second falling-film circulation pump, and the outlet of the first-stage transfer pump is connected to the second-stage forced-circulation evaporator;

[0009] Two-stage forced circulation evaporator, the two-stage forced circulation evaporator includes a two-stage forced circulation heat exchanger, a two-stage forced circulation pump, a two-stage crystallization separator and a discharge pump. The inlet of the two-stage forced circulation pump is connected to the two-stage crystallization separator, the outlet of the two-stage forced circulation pump is connected to the two-stage forced circulation heat exchanger, and the outlet of the two-stage forced circulation heat exchanger is connected to the two-stage crystallization separator;

[0010] Crystallization and salt-out system, the crystallization and salt-out system includes a thickener, a centrifuge, a mother liquor tank and a mother liquor pump. The inlet of the mother liquor pump is connected to the mother liquor tank, the mother liquor tank is connected to the centrifuge, and the centrifuge is connected to the thickener;

[0011] Steam recompression device, the steam recompression device includes a secondary separator, a compressor and a liquid accumulation pump. The inlet pipeline of the compressor is connected to the secondary separator, and the outlet pipeline of the compressor is also connected to the liquid accumulation pump;

[0012] Tail gas treatment system, the tail gas treatment system includes a vacuum pump cooler, a vacuum pump, a tail gas absorption tower, a dehydrator, a pretreatment filter and a catalytic combustion device. One side of the vacuum pump cooler is connected to the vacuum pump, one side of the vacuum pump is connected to the tail gas absorption tower, one side of the tail gas absorption tower is connected to the dehydrator, one side of the dehydrator is connected to the pretreatment filter, and one side of the pretreatment filter is connected to the catalytic combustion device.

[0013] Preferably, a raw liquid storage tank is arranged on one side of the distilled water preheater, a raw liquid pump is arranged between the distilled water preheater and the raw liquid storage tank, the distilled water preheater is connected to the raw liquid storage tank through the raw liquid pump, and the secondary steam preheater is connected to the first-stage falling film evaporator.

[0014] Preferably, the first-stage falling film heat exchanger is connected to the secondary steam preheater, and the outlet of the first-stage transfer pump is connected to the two-stage forced circulation pump in the two-stage forced circulation evaporator.

[0015] Preferably, the bottom outlet pipeline of the two-stage crystallization separator is connected to the discharge pump, the outlet pipeline of the discharge pump is connected to the thickener, the outlet pipeline of the thickener is connected to the mother liquor tank, and the outlet pipeline of the mother liquor pump is connected to the inlet of the two-stage forced circulation pump to form a cycle.

[0016] Preferably, the secondary separator is connected to the top of the two-stage crystallization separator, the outlet pipeline of the compressor is connected to the first-stage falling film heat exchanger and the two-stage forced circulation heat exchanger, the outlet of the compressor is connected to a liquid accumulation pump, the inlet of the liquid accumulation pump is connected to a distilled water tank, the outlet of the distilled water tank is connected to a distilled water pump, and the outlet of the distilled water pump is connected to the distilled water preheater.

[0017] Preferably, the secondary steam preheater is connected to the first-stage falling film heat exchanger, the compressor is connected to the second-stage forced circulation heat exchanger, and the secondary steam preheater is connected to the vacuum pump cooler.

[0018] The present invention also provides a process for evaporative crystallization of bisphenol A production wastewater using the equipment, which comprises the following steps:

[0019] Preferably, the process for resource utilization of bisphenol A production wastewater using the equipment comprises the following steps:

[0020] S1. Stock solution preheating: Feed the bisphenol A production wastewater into each preheater. The bisphenol A production wastewater first enters the distilled water preheater to exchange heat with secondary steam distilled water and fresh steam distilled water, and then enters the secondary steam preheater to exchange heat with secondary steam, and is heated to the evaporation temperature.

[0021] S2. First-stage evaporation and concentration: The preheated bisphenol A production wastewater enters the first-stage falling film evaporator for evaporation and concentration, using the heat source compressed by the compressor, and is concentrated to a concentration of 25%.

[0022] S3. Second-stage evaporation and crystallization: The concentrated solution of bisphenol A production wastewater after the first-stage evaporation and concentration is transferred by a first-stage transfer pump to the second-stage forced circulation evaporator for evaporation and concentration, also using the heat source compressed by the compressor, and is concentrated to supersaturation to precipitate crystals. The crystal slurry is then transferred by a discharge pump to a thickener for solid thickening, and finally enters a centrifuge for centrifugal dehydration to obtain sodium sulfate solid salt and high-concentration mother liquor. The high-concentration mother liquor enters the mother liquor tank, and then is transported to the inlet of the second-stage forced circulation pump through a mother liquor pump to form a cycle.

[0023] S4. Steam recompression: The secondary steam at the top of the falling film separator enters the second-stage crystallization separator, the secondary steam at the top of the second-stage crystallization separator enters the secondary separator, and the secondary steam at the top of the secondary separator enters the compressor. The secondary steam compressed by the compressor is partially introduced into the first-stage falling film heat exchanger and the second-stage forced circulation heat exchanger.

[0024] S5. Tail gas treatment system: The tail gases from the first-stage falling film heat exchanger and the second-stage forced circulation heat exchanger are discharged through a pipeline to the secondary steam preheater to exchange heat with the stock solution, then enter the vacuum pump cooler, are further condensed and then drawn into the vacuum pump, and then are discharged to a tail gas absorption tower for washing and absorption, and then enter a dehydrator for dehydration. After dehydration, they enter a pretreatment filter for water removal, oil removal, and removal of fine dust, and finally enter a catalytic combustion device to treat the tail gas to meet the discharge standards.

[0025] Preferably, the temperature rise of the compressor is 18°C, the temperature of the secondary steam obtained in steps S2 and S3 is 90°C, and the pressure is 70.1 KPa. In step S4, the secondary steam enters the compressor to be heated and pressurized to 108°C and 133.9 KPa, and then part of it enters the first falling-film heat exchanger and the second forced-circulation heat exchanger.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] 1. The equipment and process for the resource utilization of bisphenol A production wastewater of the present invention include a preheater, a first falling-film evaporator, a second forced-circulation evaporator, a crystallization and salt-out system, a steam recompression device, a tail gas treatment system, and an automatic control system. Using this equipment, the bisphenol A production wastewater containing sodium sulfate and trace amounts of acetone, phenol, etc. can be treated and discharged after passing the standards. After being treated by the MVR device, the sodium sulfate crystallizes out as a by-product, and the distilled water is recovered as makeup water for the circulating water device, obtaining valuable sodium sulfate salt and condensable water that can be discharged. The equipment has a simple structure, small floor area, low equipment investment, and realizes the automated production process of treating bisphenol A production wastewater and extracting valuable sodium sulfate, with high production efficiency and no environmental damage.

[0028] 2. The resource treatment process for bisphenol A production wastewater of the present invention is such that the raw material liquid first enters the preheating system, then enters the first evaporation and concentration system, the second evaporation and crystallization system, and the third crystallization and salt-out system. The secondary steam enters the compressor to increase the thermal energy, and the tail gas enters the tail gas treatment system; this process has simple steps, low energy consumption, and low production cost. Compared with the conventional process, adopting the MVR + tail gas treatment technology, it is a device with low energy consumption and high automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic structural diagram of the equipment and process for the resource utilization of bisphenol A production wastewater according to the embodiment of the present invention.

[0030] In the figure: 1, raw liquid storage tank; 2, raw liquid pump; 3, distilled water preheater; 4, distilled water pump; 5, secondary steam preheater; 6, distilled water tank; 7, liquid accumulation pump; 8, first falling-film circulation pump; 9, second falling-film circulation pump; 10, first transfer pump; 11, second forced-circulation pump; 12, mother liquor pump; 13, mother liquor tank; 14, centrifuge; 15, catalytic combustion device; 16, pretreatment filter; 17, vacuum pump; 18, dehydrator; 19, vacuum pump cooler; 20, tail gas absorption tower; 21, secondary separator; 22, compressor; 23, first falling-film heat exchanger; 24, falling-film separator; 25, second forced-circulation heat exchanger; 26, second crystallization separator; 27, discharge pump; 28, thickener. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0032] Embodiment 1

[0033] This embodiment provides a device and process for the resource utilization of bisphenol A production wastewater, which is a device that uses the MVR + tail gas treatment technology to evaporate and crystallize sodium sulfate in bisphenol A production wastewater and separate it, and the remaining tail gas is discharged up to standard through the tail gas treatment system. Please refer to Figure 1 , the device and process for the resource utilization of bisphenol A production wastewater mainly include a preheater, a first-stage falling-film evaporator, a second-stage forced-circulation evaporator, a crystallization and salt-out system, a steam recompression device, a tail gas treatment system, and an automatic control system. The automatic control system is PLC control. The control system is used to control the automation processes of raw liquid preheating, first-stage falling-film evaporation, second-stage forced-circulation evaporation, steam recompression, and tail gas treatment. All input and output signals can be completed by a computer installed with PLC control software, realizing the automated production process of evaporating and crystallizing sodium sulfate in bisphenol A production wastewater and discharging the remaining tail gas up to standard through the tail gas treatment system.

[0034] As Figure 1 shown, in the device, the preheater includes a distilled water preheater 3 and a secondary steam preheater 5. The preheaters are connected in sequence through pipelines. The distilled water preheater 3 is connected to a raw liquid pump 2, and the raw liquid pump 2 is connected to a raw liquid storage tank 1. The secondary steam preheater 5 is connected to the first-stage falling-film evaporator, and a temperature detection instrument is provided on the connecting pipeline. The bisphenol A production wastewater preheated by the secondary steam preheater 5 enters the first-stage falling-film evaporator after reaching the bubble point temperature through the output signal transmitted to the PLC system.

[0035] In one aspect of this embodiment, the first-stage falling-film evaporator includes a first-stage falling-film heat exchanger 23, a first falling-film circulation pump 8, a second falling-film circulation pump 9, a falling-film separator 24, and a first-stage transfer pump 10. The first-stage falling-film heat exchanger 23 is connected to the first falling-film circulation pump 8 and the second falling-film circulation pump 9. The outlet of the first-stage transfer pump 10 is connected to the second-stage forced-circulation evaporator. The first-stage transfer pump 10 is connected to the second-stage forced-circulation evaporator, and a temperature and density detection instrument is provided on the connecting pipeline. The concentrated liquid of bisphenol A production wastewater after evaporation and concentration by the first-stage falling-film evaporator is transferred to the second-stage forced-circulation evaporator after reaching the designed boiling point elevation and density through the output signal transmitted to the PLC system.

[0036] In one aspect of this embodiment, the two-stage forced circulation evaporator includes a two-stage forced circulation heat exchanger 25, a two-stage forced circulation pump 11, a two-stage crystallization separator 26, and a discharge pump 27. The inlet of the two-stage forced circulation pump 11 is connected to the two-stage crystallization separator 26, the outlet of the two-stage forced circulation pump 11 is connected to the two-stage forced circulation heat exchanger 25, the outlet of the two-stage forced circulation heat exchanger 25 is connected to the two-stage crystallization separator 26, the bottom outlet pipe of the two-stage crystallization separator 26 is connected to the discharge pump 27, the outlet pipe of the discharge pump 27 is connected to the thickener 28, the outlet pipe of the thickener 28 is connected to the mother liquor tank 13, and the outlet pipe of the mother liquor pump 12 is connected to the inlet of the two-stage forced circulation pump 11 to form a cycle. The two-stage crystallization separator 26 is connected to the discharge pump 27, and temperature and density detection instruments, as well as a sampling port for detecting the solid content, are provided on the connecting pipeline. The output signal is transmitted to the PLC system. After evaporation and crystallization by the two-stage forced circulation evaporator, when the bisphenol A production wastewater concentrate reaches supersaturation and generates crystals, it is transferred to the crystallization and salt-out system.

[0037] In one aspect of this embodiment, the crystallization and salt-out system includes a thickener 28, a centrifuge 14, a mother liquor tank 13, and a mother liquor pump 12. The inlet of the mother liquor pump 12 is connected to the mother liquor tank 13, the mother liquor tank 13 is connected to the centrifuge 14, and the centrifuge 14 is connected to the thickener 28. There is a weighing detection instrument on the pipeline connecting the thickener 28. The output signal is transmitted to the PLC system. After the crystal slurry liquid thickened by the thickener 28 reaches the designed solid content, it enters the centrifuge 14 for centrifugal dehydration to obtain sodium sulfate solid salt. The mother liquor tank 13 is connected to the mother liquor pump 12, and temperature and liquid level detection instruments are provided on the connecting pipeline. The output signal is transmitted to the PLC system. After centrifugation, the bisphenol A production wastewater concentrate is continuously transferred to the two-stage forced circulation evaporator.

[0038] In one aspect of this embodiment, the steam recompression device includes a secondary separator 21, a compressor 22, and a liquid accumulation pump 7. The inlet pipe of the compressor 22 is connected to the secondary separator 21, the outlet pipe of the compressor 22 is also connected to the liquid accumulation pump 7, the secondary separator 21 is connected to the top of the two-stage crystallization separator 26, the outlet pipe of the compressor 22 is connected to the first-stage falling film heat exchanger 23 and the two-stage forced circulation heat exchanger 25, the outlet of the compressor 22 is connected to the liquid accumulation pump 7, the inlet of the liquid accumulation pump 7 is connected to the distilled water tank 6, the outlet of the distilled water tank 6 is connected to the distilled water pump 4, and the outlet of the distilled water pump 4 is connected to the distilled water preheater 3. After the sodium sulfate crystal salt treated by MVR is used as a by-product, the distilled water tank is used to recover and supplement the circulating water device.

[0039] In one aspect of this embodiment, the secondary steam preheater 5 is connected to the first-stage falling film heat exchanger 23, the compressor 22 is connected to the second-stage forced circulation heat exchanger 25, and the secondary steam preheater 5 is connected to the vacuum pump cooler 19.

[0040] In one aspect of this embodiment, the tail gas treatment system includes a vacuum pump cooler 19, a vacuum pump 17, a tail gas absorption tower 20, a dehydrator 18, a pretreatment filter 16, and a catalytic combustion device 15. One side of the vacuum pump cooler 19 is connected to the vacuum pump 17, one side of the vacuum pump 17 is connected to the tail gas absorption tower 20, one side of the tail gas absorption tower 20 is connected to the dehydrator 18, one side of the dehydrator 18 is connected to the pretreatment filter 16, and one side of the pretreatment filter 16 is connected to the catalytic combustion device 15. The MVR + tail gas treatment technology effectively reduces energy consumption, improves the automation degree of the equipment, and reduces the environmental damage caused by tail gas.

[0041] Embodiment 2

[0042] This embodiment provides a bisphenol A production wastewater resource utilization equipment and process using the one described in Embodiment 1. The wastewater contains sodium sulfate and trace amounts of acetone, phenol and other components, which are discharged after being treated qualified. After being treated by the MVR device, the sodium sulfate crystallizes as a by-product, and the distilled water is recovered as makeup water for the circulating water device, and valuable sodium sulfate salt and condensable water that can be discharged are obtained. This process is used to treat bisphenol A production wastewater with a flow rate of 10 t / h and a concentration of 5%, and it includes the following steps:

[0043] S1. Feed liquid preheating: The bisphenol A production wastewater is stored in the feed liquid storage tank 1 and is successively passed through the distilled water preheater 3 and the secondary steam preheater 5 by the feed liquid pump 2, and exchanges heat with the secondary steam distilled water, fresh steam distilled water and secondary steam in turn, and is heated to the evaporation temperature of bisphenol A production wastewater, 95 °C. The secondary steam distilled water is the condensed water of the secondary steam separated by the evaporation of bisphenol A production wastewater and is stored in the distilled water tank 6. The secondary steam is the secondary steam generated by the falling film separator 11 and the second-stage crystallization separator, which is compressed by the compressor 22 and discharged from the first-stage falling film heat exchanger 9 and the second-stage forced circulation heat exchanger 13 to exchange heat with the feed liquid. The secondary steam is a saturated steam with a pressure of 133.9 KpaG and a temperature of 108 °C.

[0044] S2. First-stage evaporation and concentration: The preheated bisphenol A production wastewater enters the first-stage falling film heat exchanger 9, and then is pumped into the top of the first-stage falling film heat exchanger 9 by the first falling film circulation pump 8 and the second falling film circulation pump 9, and exchanges heat and evaporates from the top downwards. The secondary steam compressed by the compressor 22 is used as the heat source. During the evaporation process, the concentration of the wastewater continuously increases due to the continuous separation of water, and the concentrated liquid reaches a concentration of 25%. It is discharged into the second-stage forced circulation evaporator by the first-stage transfer pump 10.

[0045] S3. Secondary evaporation and crystallization: The concentrated liquid of bisphenol A production wastewater after primary evaporation and concentration is transferred through the primary transfer pump 10 to the secondary forced circulation pump 11, and enters the secondary forced circulation heat exchanger 13 through the secondary forced circulation pump 11 for heat exchange and evaporation. The secondary steam compressed by the compressor 22 is used as the heat source. During the evaporation process, as water is continuously separated, the concentration of the wastewater continuously increases until it reaches supersaturation and crystallizes out. The crystal slurry is then transferred through the discharge pump 27 to the thickener 28 for solid thickening, and finally enters the centrifuge 14 for centrifugal dehydration to obtain sodium sulfate solid salt and high-concentration mother liquor. The high-concentration mother liquor enters the mother liquor tank 13, and then is transported to the inlet of the secondary forced circulation pump 11 through the mother liquor pump 12 to form a cycle.

[0046] S4. Steam recompression: The secondary steam at the top of the falling film separator 24, with a temperature of 90°C and a pressure of 70.1 KPa, enters the secondary crystallization separator 26 and mixes with it. The secondary steam at the top of the secondary crystallization separator 26, with a temperature of 90°C and a pressure of 70.1 KPa, enters the secondary separator 21. The secondary steam at the top of the secondary separator 21 enters the compressor 22. After being compressed by the compressor 22, the secondary steam is heated and pressurized to 108°C and 133.9 KPa, and then enters the primary falling film heat exchanger 23 and the secondary forced circulation heat exchanger 13 to heat the material. During the process of heating the material by the secondary steam compressed by the compressor 22, it condenses into water and flows to the distilled water tank 6 for storage, and part of it is sent by the distilled water pump 4 to the distilled water preheater 3 to exchange heat with the raw material liquid, and is discharged from the system after cooling to 35°C. The compressor 22 is connected to a large secondary steam pipeline. During the startup process, the residual condensed liquid in the large pipeline is sent to the distilled water tank 6 by the condensate pump 7 and sent out of the system through the distilled water pump 4.

[0047] S5. Tail gas treatment system: The tail gases from the primary falling film heat exchanger 23 and the secondary forced circulation heat exchanger 13 are discharged through the pipeline to the secondary steam preheater 18 to exchange heat with the original liquid, then enter the vacuum pump cooler 19, are further condensed and then pumped into the vacuum pump 17, and then are discharged to the tail gas absorption tower 20 for washing and absorption, and then enter the dehydrator 18 for dehydration. After dehydration, they enter the pretreatment filter 16 for water removal, oil removal, and removal of fine dust, and finally enter the catalytic combustion device 15 to treat the tail gas up to the standard for discharge.

[0048] Experimental Example 3

[0049] Test the throughput and operating energy consumption of the bisphenol A production wastewater resource utilization equipment and process described in Test Example 2. The results are shown in Table 1:

[0050] Table 1

[0051]

[0052]

[0053] The above results show that the resource utilization equipment and process described in this embodiment have the advantages of small steam consumption, low energy consumption, high output, simple process, few equipment, and less construction investment.

[0054] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A treatment process for a resource utilization device using bisphenol A production wastewater, characterized in that: including a preheater, the preheater including a distilled water preheater (3) and a secondary steam preheater (5), the distilled water preheater (3) and the secondary steam preheater (5) being sequentially connected through pipelines; a first-stage falling film evaporator, the first-stage falling film evaporator including a first-stage falling film heat exchanger (23), a first falling film circulation pump (8), a second falling film circulation pump (9), a falling film separator (24) and a first-stage transfer pump (10), the first-stage falling film heat exchanger (23) being connected to the first falling film circulation pump (8) and the second falling film circulation pump (9), and the outlet of the first-stage transfer pump (10) being connected to a second-stage forced circulation evaporator; a second-stage forced circulation evaporator, the second-stage forced circulation evaporator including a second-stage forced circulation heat exchanger (25), a second-stage forced circulation pump (11), a second-stage crystallization separator (26) and a discharge pump (27), the inlet of the second-stage forced circulation pump (11) being connected to the second-stage crystallization separator (26), the outlet of the second-stage forced circulation pump (11) being connected to the second-stage forced circulation heat exchanger (25), and the outlet of the second-stage forced circulation heat exchanger (25) being connected to the second-stage crystallization separator (26); a crystallization and salt-out system, the crystallization and salt-out system including a thickener (28), a centrifuge (14), a mother liquor tank (13) and a mother liquor pump (12), the inlet of the mother liquor pump (12) being connected to the mother liquor tank (13), the mother liquor tank (13) being connected to the centrifuge (14), and the centrifuge (14) being connected to the thickener (28); a steam recompression device, the steam recompression device including a secondary separator (21), a compressor (22) and a liquid accumulation pump (7), the inlet pipeline of the compressor (22) being connected to the secondary separator (21), and the outlet pipeline of the compressor (22) also being connected to the liquid accumulation pump (7); a tail gas treatment system, the tail gas treatment system including a vacuum pump cooler (19), a vacuum pump (17), a tail gas absorption tower (20), a dehydrator (18), a pretreatment filter (16) and a catalytic combustion device (15), one side of the vacuum pump cooler (19) being connected to the vacuum pump (17), one side of the vacuum pump (17) being connected to the tail gas absorption tower (20), one side of the tail gas absorption tower (20) being connected to the dehydrator (18), one side of the dehydrator (18) being connected to the pretreatment filter (16), and one side of the pretreatment filter (16) being connected to the catalytic combustion device (15); the secondary steam preheater (5) is connected to the first-stage falling film heat exchanger (23), the compressor (22) is connected to the second-stage forced circulation heat exchanger (25), and the secondary steam preheater (5) is connected to the vacuum pump cooler (19); It further includes the following steps: S1. Preheating of the stock solution: The bisphenol A production wastewater is introduced into each preheater. The bisphenol A production wastewater first enters the distilled water preheater (3) to exchange heat with secondary steam distilled water and fresh steam distilled water, and then enters the secondary steam preheater (5) to exchange heat with secondary steam, and is heated to the evaporation temperature; S2. One-stage evaporation and concentration: The preheated bisphenol A production wastewater enters a one-stage falling film evaporator for evaporation and concentration, using the heat source compressed by a compressor (22), and is concentrated to a concentration of 25%. S3. Two-stage evaporation and crystallization: The concentrated liquid of the bisphenol A production wastewater after one-stage evaporation and concentration is transferred by a one-stage transfer pump (10) to a two-stage forced circulation evaporator for evaporation and concentration, also using the heat source compressed by a compressor (22), and is concentrated to supersaturation to precipitate crystals. The crystal slurry is transferred by a discharge pump (27) to a thickener (28) for solid thickening, and finally enters a centrifuge (14) for centrifugal dehydration to obtain sodium sulfate solid salt and high-concentration mother liquor. The high-concentration mother liquor enters a mother liquor tank (13), and then is transported by a mother liquor pump (12) to the inlet of a two-stage forced circulation pump (11) to form a cycle. S4. Steam recompression: The secondary steam at the top of the falling film separator (24) enters a two-stage crystallization separator (26), the secondary steam at the top of the two-stage crystallization separator (26) enters a secondary separator (21), and the secondary steam at the top of the secondary separator (21) enters a compressor (22). The secondary steam compressed by the compressor (22) is partially introduced into a one-stage falling film heat exchanger (23) and a two-stage forced circulation heat exchanger (25). S5. Tail gas treatment system: The tail gases of the one-stage falling film heat exchanger (23) and the two-stage forced circulation heat exchanger (25) are discharged through a pipeline to a secondary steam preheater (5) to exchange heat with the original solution, then enter a vacuum pump cooler (19), are further condensed and then pumped into a vacuum pump (17), and then are discharged to a tail gas absorption tower (20) for washing and absorption, and then enter a dehydrator (18) for dehydration. After dehydration, they enter a pretreatment filter (16) for water removal, oil removal, and removal of fine dust, and finally enter a catalytic combustion device (15) to treat the tail gas up to the standard for discharge.

2. The treatment process of a resource utilization device for bisphenol A production wastewater according to claim 1, characterized in that: On one side of the distilled water preheater (3), there is a raw solution storage tank (1). A raw solution pump (2) is arranged between the distilled water preheater (3) and the raw solution storage tank (1). The distilled water preheater (3) is connected to the raw solution storage tank (1) through the raw solution pump (2). The secondary steam preheater (5) is connected to the one-stage falling film evaporator.

3. The treatment process of a resource utilization device for bisphenol A production wastewater according to claim 1, characterized in that: The one-stage falling film heat exchanger (23) is connected to the secondary steam preheater (5). The outlet of the one-stage transfer pump (10) is connected to the two-stage forced circulation pump (11) in the two-stage forced circulation evaporator.

4. The treatment process of a resource utilization device for bisphenol A production wastewater according to claim 1, characterized in that: The bottom outlet pipeline of the two-stage crystallization separator (26) is connected to a discharge pump (27). The outlet pipeline of the discharge pump (27) is connected to a thickener (28). The outlet pipeline of the thickener (28) is connected to a mother liquor tank (13). The outlet pipeline of the mother liquor pump (12) is connected to the inlet of the two-stage forced circulation pump (11) to form a cycle.

5. The treatment process of a resource utilization device for bisphenol A production wastewater according to claim 1, characterized in that: The secondary separator (21) is connected to the top of the second-stage crystallization separator (26). The outlet pipeline of the compressor (22) is connected to the first-stage falling-film heat exchanger (23) and the second-stage forced-circulation heat exchanger (25). A liquid accumulation pump (7) is connected to the outlet of the compressor (22). The inlet of the liquid accumulation pump (7) is connected to a distilled water tank (6). The outlet of the distilled water tank (6) is connected to a distilled water pump (4). The outlet of the distilled water pump (4) is connected to a distilled water preheater (3).

6. The treatment process of a resource utilization device for bisphenol A production wastewater according to claim 1, characterized in that, The temperature rise of the compressor (22) is 18 °C. The temperature of the secondary steam obtained in steps S2 and S3 is 90 °C, and the pressure is 70.1 KPa. In step S4, the secondary steam enters the compressor (22), is heated and pressurized to 108 °C and 133.9 KPa, and then part of it enters the first-stage falling-film heat exchanger (23) and the second-stage forced-circulation heat exchanger (25).

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