Resin-based synthetic bisphenol A manufacturing method and equipment

Abstract

To provide a production process for synthetic bisphenol A by a resin process and a device.SOLUTION: The present invention employs: a condensation reaction unit for generating bisphenol A by performing a catalytic condensation reaction between phenol and acetone under the action of a resin catalyst; an adduct crystallization unit for performing adduct crystallization after mixing a concentrated solution from the condensation reaction with adduct crystals recovered after melting; a liquid-phase dephenolization unit for obtaining a bisphenol A product by melting the adduct; a secondary adduct crystallization unit for recovering phenol and bisphenol A from a mother solution; a solvent recycling unit for recovering unreacted phenol and acetone and for sending phenol-containing waste water to sewage treatment; and a cracking and rearrangement unit for recovering phenol from the mother solution, for first cracking bisphenol A and 2,4-bisphenol A therein, rearranging them, and converting them into bisphenol A to return to the system.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for producing bisphenol A, and more particularly to a method and apparatus for producing synthetic bisphenol A by a resin method. [Background technology]

[0002] The molecular formula of bisphenol A (BPA) is C 15 H 16 O2, molecular weight is 228.29, and chemical structure is as follows:

[0003] [ka]

[0004] Bisphenol A is a white crystal that is soluble in ethanol, ether, and acetic anhydride, has very low solubility in water (1:2820 by weight), and is slightly soluble in boiling water (1:130 by weight). Bisphenol A can form crystalline adducts with various inorganic and organic substances (phenol, isopropyl alcohol, amines, ammonia, etc.), usually in equimolar ratios. These adducts are highly unstable and may decompose when heated, washed with water, or under normal pressure, vacuum, or inert gas.

[0005] Bisphenol A is an important industrial chemical and is the main raw material for the production of epoxy resins and polycarbonates. It is also used in the production of polymeric materials such as polysulfone resins, phenolic unsaturated resins, polyarylates, polyetherimides, heat stabilizers for polyvinyl chloride, and antioxidants for rubber.

[0006] Currently, bisphenol A is typically produced by the condensation reaction of excess phenol and acetone in the presence of an acidic catalyst, most commonly a strongly acidic cation exchange resin. The resulting reaction mixture contains bisphenol A as well as unreacted phenol, acetone, by-product water, bisphenol A isomers, triphenols, chromanols, and more than 10 other substances. The typical method for recovering bisphenol A is to crystallize the reaction mixture obtained by the condensation reaction, separate the solid and liquid, wash the crude crystals, and then remove the phenols from the crystals.

[0007] Patent Document 1 discloses a method for increasing the concentration of bisphenol A by recycling a reaction liquid in order to reduce energy consumption. In this method, acetone, water, and a portion of the phenol are removed from the reaction liquid, which is then sent to a vacuum evaporation system to remove the phenol. A high-purity bisphenol A melt is obtained through multiple crystallization and melt recycling processes, and the vacuum-dehydrated material is returned to the reaction inlet.

[0008] Patent Document 2 discloses an optimization method for producing bisphenol A reaction system, which includes a step of sequentially subjecting a mother liquor obtained by treating at least a portion of the reaction liquid to an isomerization reaction, concentration, partial preconcentration, decomposition, and rearrangement reaction step; and a step of operating a reaction system for producing bisphenol A, in which the isomerization reaction and the rearrangement reaction are simultaneously carried out in an isomerization-rearrangement reactor to form a circulating operation system, and isopropylphenol produced in the decomposition process enters a phenol recovery system together with light fractions in the partial preconcentration step and is separated from phenol together with mixed polyphenols.

[0009] Patent Document 3 discloses a method for reducing isopropylphenol in the production of bisphenol A reaction system, in which at least a part of the reaction liquid obtained after catalytic condensation reaction of an excess amount of phenol with acetone in a condensation reactor is subjected to an isomerization-cracking-rearrangement process to obtain a rearrangement liquid, and the rearrangement liquid containing isopropylphenol is subjected to a concentration process to allow the isopropylphenol to enter a phenol recovery system, where it escapes from phenol together with mixed polyphenols, and the mass percent content of isopropylphenol in the condensation reactor is reduced to 0.25% or less.

[0010] To summarize the above and other references, in current bisphenol A production processes, most reaction systems are one- or two-stage tubular reactors connected in series. As the reaction progresses, the heat of reaction is released, causing the temperature of the system to continue to rise, and the content of by-product water also continues to increase. The high temperature and the presence of water inhibit the forward reaction, reducing the equilibrium conversion rate, and making it impossible to achieve an ideal reaction rate and conversion rate.

[0011] From the viewpoint of the reaction system, currently, there is a method to increase the conversion rate of phenol by returning the stream from the separation section to the reactor, but no effective method has been proposed to solve the problem of the temperature inside the reactor being too high. A rectification column is used after the reactor to extract light components, and water is involved in the reaction throughout the process, which is not helpful in promoting the forward reaction. The rectification column consumes a lot of energy and is not suitable for separating materials at this point. From the perspective of separation systems, there are currently multiple stages of crystallization-washing-melting processes, which result in long overlapping processes. The root cause is the low efficiency of solid-liquid separation equipment, which can prevent the system from achieving its separation goals. From the perspective of overall energy utilization, the entire process involves many endothermic and radiative processes, including preheating, condensation, evaporation, etc., among which, different evaporation methods have significant differences in energy utilization efficiency. The methods used in many industrial examples and patents are basically simple one-stage evaporation or one-stage rising film / falling film evaporation, which do not fully utilize the energy gradient and have little heat exchange between streams, resulting in significant energy waste. From the perspective of the overall material circulation, the layout of the circulation streams between each section is unreasonable, which leads to serious back-mixing of materials and increases the burden on the separator and power equipment.

[0012] In short, the current bisphenol A production method has more or less defects from part to whole, and in order to improve the purity of the product and reduce energy consumption, it is necessary to adjust the direction of some circulating streams in the entire process, increase the heat exchange between process streams in the entire process, and focus on improving some processes and equipment. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] Chinese Patent No. CN200910030415.2 [Patent Document 2] Chinese Patent No. CN202111654111.0 [Patent Document 3] Chinese Patent No. CN202111165633.9 Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention provides a method and apparatus for synthesizing bisphenol A, which includes a reactor external circulation heat exchanger, a light-end removal tank between the two reaction stages, a pressure separator, a double-effect falling film evaporator, and an isomerization reactor, and also adjusts the direction of a portion of the circulation stream in the entire process to increase the heat exchange between process streams in the entire process, thereby achieving the objectives of improving the purity of the products and circulation materials, reducing energy consumption, and improving bisphenol A selectivity. [Means for solving the problem]

[0015] A method for producing synthetic bisphenol A by a resin method, comprising the following steps: (1) A process comprising a condensation reaction unit for producing bisphenol A by catalytic condensation reaction of phenol and acetone under the action of a resin catalyst, the reactors of which comprise a first-stage reactor and a second-stage reactor, and providing an external circulation heat transfer between the first-stage reactor and the second-stage reactor, and flash evaporation dehydration between the first-stage reactor and the second-stage reactor; (2) A process of mixing the condensation reaction concentrate with the recovered adduct crystals after melting, followed by crystallization of the adduct, followed by pressurization, drum rotation, and filtration, followed by adding phenol to the adduct crystal-containing solution, uniformly stirring and washing, and then centrifuging to obtain the adduct crystals, comprising a first adduct crystallization unit, and separating the solid phase and the liquid phase in a pressure separator; (3) a liquid-phase dephenolization unit for extracting phenol from the adduct melt, granulating, and packaging to obtain the bisphenol A product; (4) a secondary adduct crystallization unit for recovering phenol and bisphenol A in the mother liquor, separating phenol and bisphenol A by double-effect falling film evaporation, and converting the by-product to bisphenol A in an isomerization reactor; (5) a solvent recovery unit for recovering unreacted phenol and acetone and sending the phenol-containing wastewater to wastewater treatment; (6) A decomposition and rearrangement unit that removes impurities generated during the manufacturing process, recovers phenol from the mother liquor, and first decomposes and rearranges the bisphenol A and 2,4-bisphenol A contained in the mother liquor, converting them into bisphenol A and returning them to the system.

[0016] In the production method for synthetic bisphenol A by the resin method of the present invention, raw material acetone, recovered acetone, and recycled phenol are sent to the condensation reaction unit (100#) for reaction, and after simple separation of the product and unreacted raw materials, the reaction liquid is sent to the adduct crystallization unit (200#), and the hydrous phenol is sent to the solvent recovery unit (500#). A portion of the raw material phenol is added from the adduct crystallization unit and used to wash the upstream reaction liquid, recovered phenol from the dephenolization purification unit (300#), and the adduct crystal melt from the mother liquor recovery unit (400#). After washing, the first-stage centrifuged mother liquor / washing liquid and the second-stage centrifuged mother liquor are sent to the mother liquor recovery unit (400#), and the adduct crystal melt is used for dephenolization purification. The phenol is then sent to the dephenolization unit, where it is converted into the final product BPA, while the hydrous phenol is sent to the solvent recovery unit. Part of the raw phenol is added from the mother liquor recovery unit and used to wash the mother liquor, washings, recovered phenol, and recovered BPA from the decomposition and rearrangement unit (600#). The mother liquor from the second stage of centrifugation is then sent to the decomposition and rearrangement unit, where ethylbenzene is added as an azeotrope to the solvent recovery unit, the recovered acetone is sent to the condensation reaction unit, the recovered phenol is sent to the mother liquor recovery unit, and wastewater is discharged outside the system. The decomposition and rearrangement unit receives the mother liquor from the second stage of centrifugation and decomposes it, returns the recovered BPA to the mother liquor recovery unit, and sends isopropyl phenol and wastewater out of the system.

[0017] In the condensation reaction unit (100#), fresh acetone after purification at a flow rate of 14,000 to 16,000 kg / h is metered and fed proportionally to the first-stage reactor (102) and the second-stage reactor (112), respectively. The acetone fed to the reactor (102) is mixed with recovered phenol from the decomposition feed preheater (601) and materials from the first-stage circulation pump (105), enters the first-stage cooler (101), and is cooled by circulating water before entering the first-stage reactors (102 to 104). A part of the reaction liquid flowing out of the first-stage reactor (104) is fed to the first-stage circulation pump (105). The remaining part is circulated by a circulation pump (105) and returned to the first-stage reactor (102), with a circulation flow rate of 455,000 to 520,000 kg / h. The remaining part is heated by a dehydration flash heater (106) and then flows into a dehydration flash evaporator (107) to remove some of the water. The flash vapor from the dehydration flash evaporator (107) is condensed and cooled by a first flash evaporator condenser (108) and a second flash evaporator condenser (109). The condensate containing water, acetone, and phenol flows into a light fraction receiving tank (124), and the tail gas is sent to a vacuum system. The dehydrated material from the dehydration flash evaporator (107) is mixed with recovered acetone and fresh acetone from the second stream, and then sent to the second-stage cooler (111) by the second-stage feed pump (110). There, it is cooled with circulating water and then enters the second-stage reactors (112-114). The condensation reaction liquid from the second-stage reactor (114) is mixed with the bottom liquid from the phenol absorption tower (306), then enters the adsorption column (115), and then is heated by heat exchange with the bottom liquid of the light fraction removal tower (117) in the preheater (116), and then enters the light fraction removal tower (117). The water, unreacted acetone, and a part of the phenol in the reaction mixture evaporate from the top of the column and are condensed in a condenser (122) and an aftercooler (123). The tail gas then enters a vacuum system, and the condensate flows into a light fraction receiving tank (124), and is then sent to a solvent recovery unit (500#) by a discharge pump (125) to recover phenol and acetone. The light fraction removal column reboiler (118) is heated with low-pressure steam, and the bottom product is concentrated. The bottom product is then sent by a discharge pump (119), and is then subjected to heat exchange in a preheater (116) to lower its temperature, and is then sent to a condensation reaction mixture receiving tank (120).

[0018] The adduct crystallization unit (200#): The reaction concentrate from the condensation reaction liquid discharge pump (121) and the adduct crystal melt recovered from the mother liquor recovery unit (400#) of the crystal melting device circulation pump (427) are mixed in the crystallization supply buffer tank (201), then sent out by the crystallization supply pump (202), cooled by the supply cooler (203), and then enters the main circulation type crystallizer (204). The crystal slurry is then pumped into the main circulation type crystallizer (204) by the crystallization circulation pump (205). After being pumped out from the crystallizer (204), it enters the crystallization cooler (206) where the heat of crystallization is removed under the cooling effect of deionized water. The crystal slurry flowing out from the main circulation crystallizer (204) is continuously sent to the pressurized main separator (207) by the flow control valve for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump (214). The separated mother liquor and washing liquid are sent to the main separator mother liquor / washing liquid tank (206). The phenol from the phenol discharge pump (311) is mixed with the filtered adduct crystals in the slurry mixing and washing tank (210) and washed. The crystal slurry after the slurry mixing is sent to the second stage pressurized main separator (212) by the corresponding crystal slurry pump (211), where solid-liquid separation takes place. The filtrate is then sent to the slurry mixing centrifuge mother liquor tank (401) by the slurry mixing centrifuge mother liquor pump (212). The filtrate enters the liquid tank (213), is pumped out by the slurry mixed washing mother liquor pump (214), and is sent to the pressurized main separator (207) and the pressurized sub-separator (423) respectively for phenol washing. The filter cake is removed by a centrifuge and goes into the crystal melter (215). The material in the crystal melter (215) is sent to the heater (217) by the corresponding crystal melt circulation pump (216) to be heated, and then returned to the crystal melter (215).

[0019] In the phenol removal purification unit (300#), the adduct melt from the phenol removal feed pump (218) enters the falling film type phenol removal device (301), where it is evaporated by heating with steam and enters the gas-liquid separation tank (302). The liquid phase enters the top of the steam stripping phenol removal device (305). The gas phase is condensed by the condenser (303). The tail gas enters the vacuum system and the condensate enters the phenol tank (310). Fresh phenol from the tank area with a flow rate of 42,756 to 48,864 kg / h enters the fresh phenol tank (313) and is pumped out by the fresh phenol pump (314). A portion is metered and sent to the phenol tank (310), and the rest is sent to the recovered phenol tank (416). The phenol in the phenol tank (310) is pumped out by the phenol discharge pump (311) and cooled to a set value by the washed phenol cooler (312) before being mixed with the slurry. The water vapor is sent to a washing tank (210) to produce washed phenol, and after being heated by an electric steam superheater (304), it enters the bottom of the steam stripping dephenolization unit (305) as steam stripping steam. The liquid bisphenol A obtained at the bottom of the tower is pumped out by a BPA melt pump (315), molded, granulated, and packaged in a packaging machine (316) to produce a bisphenol A product. The vapor from the top of the tower enters the bottom of the phenol absorber (306) and undergoes gas-liquid mass transfer with the absorbed phenol added from the top. The gas exiting the tower enters the phenol absorber condenser (309), the tail gas enters a vacuum system, and the condensate, which is hydrous phenol, enters an ethylbenzene tank (526). The bottom liquid, which is a bisphenol A phenol solution, is sent to a cooler (308) by a phenol circulation pump (307) to be cooled and then returned to the top of the phenol absorber (306).

[0020] In the mother liquor recovery unit (400#), the material from the mother liquor receiving tank (401) is sequentially sent by the feed pump (402) to the first feed preheater (403) and the second feed preheater (404). The first feed preheater (403) is a thermally coupled heat exchanger, and the heat medium is the gas phase material from the gas-liquid separation tank (411). The second feed preheater (404) is also a thermally coupled heat exchanger, and the heat medium is phenol from the recovery phenol pump (419). After the two-stage preheating, the material is metered and divided into two parts. One part enters the high-pressure falling film evaporator (406), and the other part enters the high-pressure falling film evaporator (406). The vapor is evaporated by the heat of steam, and the gas and liquid phases flowing out from the bottom of the high-pressure falling film evaporator (406) enter the first-stage gas-liquid separation tank (407). The liquid phase is pumped into the gas-liquid separation tank (411) by the pump (410). The gas phase enters the low-pressure falling film evaporator (405) as a heat medium. After condensation, the gas and liquid phases are separated in the second-stage gas-liquid separation tank (408). The liquid phase enters the recovery phenol tank (416). The gas phase enters the tail gas condenser (409) and is further condensed by circulating water. The condensate enters the recovery phenol tank (416) and the tail gas condenser (409) is further condensed by circulating water. The gas is sent to the vacuum system, and the other part of the preheated mother liquor is heated and evaporated in the low-pressure falling film evaporator (405). The gas-liquid two-phase material flowing out from the bottom of the low-pressure falling film evaporator (405) enters the third-stage gas-liquid separation tank (411). Part of the gas phase material enters the first-stage feed preheater (403) as a heat medium, and the rest is condensed in the condenser (414) under the action of circulating water. The tail gas from the first-stage feed preheater (403) and the condenser (414) merges and enters the aftercooler (415), where it is further condensed under the action of circulating water. The tail gas is then sent to the vacuum system. The condensate from the first-stage feed (403), condenser (414) and aftercooler (415) flows into the recovered phenol tank (416). The material in the recovered phenol tank (416) is pumped into the recovered phenol storage tank (418) by the phenol discharge pump (417), and then pumped out by the recovered phenol pump (419). The temperature is lowered by heat exchange in the second-stage feed preheater (404) and the decomposition feed preheater (601), and then the material is sent to the first-stage cooler (101) of the condensation reactor and the outlet of the phenol circulation pump (307), respectively.The liquid phase material in the third-stage gas-liquid separation tank (411) is a concentrated bisphenol A phenol solution, which is pumped out by a crystallization feed pump (412), passed through a crystallization feed cooler (413) and cooled with circulating water, and then enters a recovery crystallizer (420). The adduct crystal slurry is pumped out of the recovery crystallizer (420) by a crystallization circulation pump (422), and then enters a crystallization cooler (421) where the heat of crystallization is cooled with deionized water. The crystal slurry discharged from the recovery crystallizer (420) is continuously sent to the pressure sub-separator (423) for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump (214). The mother liquor separated from the pressure sub-separator (423) enters the mother liquor receiving tank (429) and is discharged by the mother liquor discharge pump (430). After being preheated by the mother liquor heater (431), a part of it is used for isomerization. The reaction mixture is sent to the reactor (432), where a portion of the 2,4-bisphenol A, triphenol, chromanol, etc. contained therein is converted to bisphenol A before entering the mother liquor receiving tank (401), and the remaining portion is sent to the cracking / transposition unit (600#) for cracking / transposition. The wash liquid from the pressure secondary separator (423) enters the wash liquid receiving tank (424) and is sent to the mother liquor receiving tank (401) by the wash liquid discharge pump (425). A portion of the reaction mixture introduced from the main separator and metered by the condensation reaction concentrate discharge pump (121) is mixed with the filtered adduct crystals in the tail gas condenser (409). The material in the tail gas condenser (409) is sent to the heater (428) by the corresponding crystal melt circulation pump (427) to be heated before returning to the tail gas condenser (409). The material in the tail gas condenser (409) is sent to the crystallization supply buffer tank (201) by the crystal melt circulation pump (427).

[0021] The solvent recovery unit (500#) includes a dehydration tower (502) as an azeotropic distillation tower, with ethylbenzene as the azeotropic agent. The material from the light fraction discharge pump (125) is mixed with the material from the ethylbenzene feed pump (527) and then preheated by low-pressure steam in the dehydration tower feed preheater (501) before entering the dehydration tower (502). The overhead gas directly enters the acetone recovery tower (504). The bottom liquid is phenol containing ethylbenzene, which is sent to the phenol recovery tower (519) by the tower boiler discharge pump (518). The overhead gas from the acetone recovery tower (504) is condensed through an acetone tower condenser (506) and an aftercooler (507). The tail gas is sent to a vacuum system, and the condensate enters the acetone tower reflux tank (508) and is pumped out by the acetone tower reflux pump (509).One strand is sent as reflux to the top of the acetone recovery tower, and the other strand is sent as recovered acetone to the suction port of the second-stage feed pump (110) of the condensation reaction unit (100#) reactor. The bottom product enters the phase separator (510) to form an aqueous phase and an organic phase. The aqueous phase material is pumped out by the aqueous phase discharge pump (511) and cooled by coolers (512, 513), then enters the phase separator (514) for further phase separation. The organic phase flows into the phase separator (510). The aqueous phase is discharged from the boundary region as wastewater of the apparatus by a wastewater pump (516) and is subjected to biochemical treatment. The organic phase of the phase separator (510) is discharged by an ethylbenzene discharge pump (515), a part of which is returned to the top of the dehydration tower (502) as reflux, and the rest is cooled by an ethylbenzene cooler (517) and then enters the vacuum pump as an auxiliary working fluid for the ethylbenzene liquid ring vacuum pump. By adjusting the flow rate of the heating steam in the reboiler (505), the ascending vapor in the tower is The amount of gas is controlled, and the material from the column tank discharge pump (518) of the dehydration column (502) enters the phenol recovery column (519). The overhead gas is condensed through the phenol column condenser (522) and aftercooler (523). The tail gas enters the vacuum system, and the condensate enters the reflux tank (524). A portion of it is returned to the top of the column as reflux by the reflux pump (525). The remaining portion overflows into the ethylbenzene tank (526). The ethylbenzene tank (526) is used for the phenol absorption column condensate. The column receives hydrous phenol from the condenser (309), displaced ethylbenzene from the vacuum system, and make-up ethylbenzene. The material in the ethylbenzene tank (526) is fed to the dehydration column (502) via the ethylbenzene feed pump (527). The column bottom liquid, which is phenol containing no ethylbenzene, is sent to the recovered phenol storage tank (416) by the column bottom discharge pump (521). The amount of rising steam in the column is controlled by adjusting the flow rate of heating steam from the reboiler (520).

[0022] In the cracking / rearrangement unit (600#), the mother liquor from the mother liquor discharge pump (430) is preheated by the cracking / rearrangement feed preheater (601) and then enters the falling film evaporator (602). The cracking / rearrangement feed preheater (601) is a thermally coupled heat exchanger, and the heat medium is the recovered phenol from the second-stage feed preheater (404). The mother liquor is evaporated in the falling film evaporator (602) by heating with steam. The gas-liquid two-phase material enters the gas-liquid separation tank (603). The liquid phase enters the column pot of the cracking reactor (610), and the gas phase enters the p-isopropylphenol decomposition column (612). The bottom liquid of the p-isopropylphenol removal column (604) is a heavy fraction containing p-isopropylphenol, which is discharged to the outside of the system via a discharge pump (606) and incinerated. The overhead gas is condensed and cooled by a condenser (607). The tail gas enters a vacuum system, and the condensate enters a reflux tank (608) and is then pumped out by a reflux pump (609). A portion of the condensate is returned to the top of the p-isopropylphenol removal column (604) as reflux, and the other portion is used as reflux in a decomposition reactor (610) for decomposition. The material flows into the top of the decomposition reactor (610), and the material overflowing from the reflux tank (608) flows into the decomposition product tank (614). The amount of steam rising in the column is controlled by adjusting the flow rate of the heated steam in the reboiler (605). The material from the gas-liquid separation tank (603) flows into the decomposition reactor (610) and is then sent to the decomposition reactor heater (612) by the decomposition reaction circulation pump (611). The material is heated, and then returned to the decomposition reactor (610) with a certain amount of alkaline solution added as a catalyst for the decomposition reaction. The tar thus obtained is discharged outside the system via the cracking reaction circulation pump (611) and incinerated. The overhead gas from the cracking reactor (610) is condensed and cooled in the cracking product condenser (613). The tail gas enters a vacuum system, and the condensate enters the cracking product tank (614). It is then sent to the circulation cooler (616) by the rearrangement reaction feed pump (615) and cooled. A portion of the condensate is circulated back to the cracking product tank (614), while the other portion is used as a feed for the rearrangement reactor (617). The rearranged product is returned to the mother liquor receiving tank (401).

[0023] Apparatus for realizing the method for producing synthetic bisphenol A (1): The cooling side outlet of the cracking supply preheater (601) is joined with the discharge port of the first-stage circulation pump (105) and then connected to the cooling side inlet of the first-stage cooler (101), the cooling side outlet of the first-stage cooler (101) is connected to the inlet of the first-stage reactor (102), the outlet of the first-stage reactor (102) is connected to the inlet of the first-stage reactor (103), the outlet of the first-stage reactor (103) is connected to the inlet of the first-stage reactor (104), the outlet of the first-stage reactor (104) is branched into two, each of which is fed to the first-stage circulation pump (105) The suction port of the second-stage supply pump (110) is connected to the inlet of the second-stage supply pump (110) and the inlet of the heating side of the dehydration flash evaporation heater (106). The outlet of the heating side of the dehydration flash evaporation heater (106) is connected to the inlet of the dehydration flash evaporation unit (107). The outlet of the vapor phase of the dehydration flash evaporation unit (107) is connected to the inlet of the cooling side of the first flash evaporation condenser (108). The outlet of the liquid phase of the second-stage supply pump (110) is connected to the outlet of the acetone tower reflux pump (509) and then to the suction port of the second-stage supply pump (110). The outlet of the second-stage supply pump (110) is connected to the inlet of the cooling side of the second-stage cooler (111). The outlet of the cooling side of the second-stage cooler (111) is connected to the inlet of the second-stage supply pump (110). The outlet of the second-stage reactor (112) is connected to the inlet of the second-stage reactor (113), the outlet of the second-stage reactor (113) is connected to the inlet of the second-stage reactor (114), the gas phase outlet on the cooling side of the flash evaporation first condenser (108) is connected to the cooling side inlet of the flash evaporation second condenser (109), the liquid phase outlet of the flash evaporation first condenser (108) joins with the liquid phase outlet on the cooling side of the flash evaporation second condenser (109) and is then connected to the inlet of the light fraction receiving tank (124), and the gas phase outlet on the cooling side of the flash evaporation second condenser (109) is connected to the inlet of the light fraction receiving tank (124). the outlet of the second-stage reactor (114) is joined to the discharge port of a phenol circulation pump (307) and then connected to the inlet of an adsorption column (115); the outlet of the adsorption column (115) is connected to the heating side inlet of a light fraction removal column feed preheater (116); the heating side outlet of the light fraction removal column feed preheater (116) is connected to the inlet of the light fraction removal column (117); the outlet of the light fraction removal column (117) is connected to the suction port of a light fraction removal column column feed preheater (119); the discharge port of the light fraction removal column column feed preheater (119) is connected to the cooling side inlet of the light fraction removal column column feed preheater (116);The cooling side outlet of the light fraction removal column feed preheater (116) is connected to the inlet of a condensation reaction liquid receiving tank (120), the outlet of the condensation reaction liquid receiving tank (120) is connected to the suction port of a condensation reaction liquid discharge pump (121), the discharge port of the condensation reaction liquid discharge pump (121) is branched into two, which are respectively connected to the filter cake outlet of the pressure sub-separator (423) and the inlet of the crystallization feed buffer tank (201), and the top outlet of the light fraction removal column (117) is connected to the light fraction removal column condenser The cooling side gas phase outlet of the light fraction removal column condenser (122) is connected to the cooling side inlet of the light fraction removal column aftercooler (123), the cooling side gas phase outlet of the light fraction removal column aftercooler (123) is connected to a vacuum unit, and the cooling side liquid phase outlet of the light fraction removal column condenser (122) joins with the cooling side liquid phase outlet of the light fraction removal column aftercooler (123) and is then connected to the inlet of the light fraction receiving tank (124).

[0024] The apparatus for realizing the method for producing synthetic bisphenol A (2): The outlet of the condensation reaction liquid discharge pump (121) is connected to the outlet of the circulation pump (427) of the crystal melting device, and then connected to the inlet of the crystallization supply buffer tank (201). The outlet of the crystallization supply buffer tank (201) is connected to the suction port of the main crystallizer supply pump (202). The outlet of the main crystallizer supply pump (202) is connected to the cooling side inlet of the supply cooler (203) of the main crystallizer. The cooling side outlet of the supply cooler (203) of the main crystallizer and the cooling side outlet of the external circulation crystallization cooler (206) are both main circulation type crystallizers. The outlet of the main circulation crystallizer (204) is connected to the inlet of the crystallization circulation pump (205) and the mother liquor inlet of the first-stage pressurized main separator (207), respectively. The discharge port of the crystallization circulation pump (205) is connected to the cooling side inlet of the external circulation crystallization cooler (206). The mother liquor / washing liquid outlet of the first-stage pressurized main separator (207) is connected to the inlet of the first-stage main separator mother liquor / washing liquid tank (208). The outlet of the first-stage main separator mother liquor / washing liquid tank (208) is connected to the suction port of the washing phenol pump (209), and the discharge port of the washing phenol pump (209) is connected to the inlet of the washing phenol pump (209). is connected to the inlet of the mother liquor receiving tank (401), the discharge port of the phenol delivery pump (311) is connected to the filter cake outlet of the first-stage pressurized main separator (207) and the inlet of the slurry mixing washing tank (210) in turn, the outlet of the slurry mixing washing tank (210) is connected to the suction port of the crystal slurry pump (211), the discharge port of the crystal slurry pump (211) is connected to the mother liquor inlet of the second-stage pressurized main separator (212), the mother liquor outlet of the second-stage pressurized main separator (212) is connected to the inlet of the second-stage main separator mother liquor tank (213), and the outlet of the second-stage main separator mother liquor tank (213) is connected to the inlet of the second-stage main separator mother liquor tank (213). is connected to the suction port of the slurry mixed washing mother liquor pump (214), and the discharge port of the slurry mixed washing mother liquor pump (214) is branched into two, which are respectively connected to the washing liquid inlet of the pressure secondary separator (423) and the washing liquid inlet of the first-stage pressure main separator (207). The filter cake outlet of the second-stage main separator mother liquor tank (213) and the heating side outlet of the melting heater (217) are both connected to the inlet of the crystal melting device (215), and the outlet of the crystal melting device (215) is connected to the suction port of the crystal melting device circulation pump (216) and the suction port of the dephenolization supply pump (218), respectively.The outlet of the circulation pump (216) of the crystal melting device is connected to the inlet of the heating side of the melting heater (217), and the outlet of the dephenolization supply pump (218) is connected to the inlet of the liquid film descending type dephenolization device (301).

[0025] Apparatus for realizing the method for producing synthetic bisphenol A (3): The discharge port of the dephenolization supply pump (218) is connected to the inlet of a liquid film falling type dephenolization apparatus (301), the outlet of the liquid film falling type dephenolization apparatus (301) is connected to the inlet of a gas-liquid separation tank (302), the gas phase outlet of the gas-liquid separation tank (302) is connected to the cooling side inlet of a condenser (303) of a steam stripping dephenolization tower, the gas phase outlet of the condenser (303) of the steam stripping dephenolization tower is connected to a vacuum unit, and the liquid phase outlet is connected to a phenol tank (31). The outlet of the phenol tank (310) is connected to the suction port of a phenol discharge pump (311), the discharge port of the phenol discharge pump (311) is connected to the cooling side inlet of a phenol cooler (312), the liquid phase outlet of the liquid separation tank (302) is connected to the top inlet of a steam stripping dephenolization tower (305), the top outlet of the steam stripping dephenolization tower (305) is connected to the inlet of the kettle of the phenol absorption tower (306), the outlet of the kettle is connected to the suction port of a BPA melting pump (315), and the inlet of the kettle is connected to the steam The outlet of the phenol absorber (306) is connected to the heating side outlet of the stripping steam superheater (304), the discharge port of the BPA melt pump (315) is connected to the inlet of the packaging machine (316), the top outlet of the phenol absorber (306) is connected to the cooling side inlet of the phenol absorber condenser (309), the outlet of the tank is connected to the suction port of the phenol circulation pump (307), the top inlet is connected to the cooling side outlet of the spray phenol cooler (308), the gas phase outlet of the cooling side of the phenol absorber condenser (309) is connected to a vacuum unit, and the liquid phase outlet is connected to the inlet of the ethylbenzene tank (526). The outlet of the phenol circulation pump (307) is branched into two, one of which is combined with the outlet of the second-stage reactor (114) and then connected to the inlet of the adsorption column (115), the other of which is combined with one stream from the cooling side outlet of the cracking feed preheater (601) and then connected to the cooling side inlet of the spray phenol cooler (308), the outlet of the fresh phenol tank (313) is connected to the suction port of the fresh phenol pump (314), the outlet of the fresh phenol pump (314) is branched into two, one of which is connected to the inlet of the recovered phenol tank (416),The other one joins with the cooling side outlet of the phenol cooler (312) and then connects to the filter cake outlet of the first-stage pressurized main separator (207).

[0026] Apparatus for realizing the method for producing synthetic bisphenol A (3): The inlet of the mother liquor receiving tank (401) is connected to the discharge port of the washing phenol pump (209), the outlet of the rearrangement reactor (617), the discharge port of the washing liquid dispensing pump (425), and the outlet of the isomerization reactor (432), respectively. The outlet of the mother liquor receiving tank (401) is connected to the suction port of the feed pump (402) of the falling film evaporator. The feed pump (402) of the falling film evaporator is connected to the inlet of the heating side of the first-stage feed preheater (403). The outlet of the heating side of the first-stage feed preheater (403) is connected to the heating side of the second-stage feed preheater (404). The second-stage supply preheater (404) has a heating-side outlet branched into two, which are connected to the heating-side inlets of the low-pressure liquid film falling evaporator (405) and the pressurized liquid film falling evaporator (406), respectively. The heating-side outlet of the pressurized liquid film falling evaporator (406) is connected to the inlet of the first-stage gas-liquid separation tank (407). The vapor-phase outlet of the first-stage gas-liquid separation tank (407) is connected to the cooling-side inlet of the low-pressure liquid film falling evaporator (405). The liquid-phase outlet is connected to the suction port of the discharge pump (410) of the first-stage separation tank. The discharge port of the discharge pump (410) of the first-stage separation tank is connected to the gas-phase inlet of the third-stage separation tank. The heating side outlet of the low-pressure falling film evaporator (405) is connected to the inlet of the third-stage gas-liquid separation tank (411), the cooling side outlet is connected to the inlet of the second-stage gas-liquid separation tank (408), the gas phase outlet of the second-stage gas-liquid separation tank (408) is connected to the inlet of the tail gas condenser (409), the liquid phase outlet is merged with the liquid phase outlet of the tail gas condenser (409) and then connected to the inlet of the recovery phenol tank (416), the liquid phase outlet of the third-stage gas-liquid separation tank (411) is connected to the suction port of the crystallizer feed pump (412), and the gas phase outlets are divided into two. The branched flow is connected to the cooling-side inlet of the first-stage supply preheater (403) and the cooling-side inlet of the condenser (414), respectively. The cooling-side vapor outlet of the first-stage supply preheater (403) joins with the cooling-side vapor outlet of the condenser (414) and is then connected to the cooling-side inlet of the aftercooler (415). The cooling-side liquid outlets of the first-stage supply preheater (403), condenser (414), and aftercooler (415) join and are then connected to the inlet of the recovered phenol tank (416). The discharge port of the crystallizer supply pump (412) is connected to the cooling-side inlet of the crystallizer supply cooler (413).The discharge port of the fresh phenol pump (313) and the discharge port of the kettle discharge pump (521) of the phenol recovery tower are both connected to the inlet of the recovered phenol tank (416), the outlet of the recovered phenol tank (416) is connected to the inlet of the recovered phenol storage tank (418), the outlet of the recovered phenol storage tank (418) is connected to the suction port of the recovered phenol pump (419), the discharge port of the recovered phenol pump (419) is connected to the cooling side inlet of the second stage supply preheater (404), and the cooling side inlet of the second stage supply preheater ( The cooling side outlet of the crystallizer (404) is connected to the cooling side inlet of the cracking feed preheater (601), the inlet of the recovery crystallizer (420) is connected to the cooling side outlet of the crystallizer feed cooler (413) and the cooling side outlet of the external circulation crystallization cooler (421), respectively, and the outlets are connected to the crystallization circulation pump (422) and the mother liquor inlet of the pressure sub-separator (423), respectively, the discharge port of the crystallization circulation pump (422) is connected to the cooling side inlet of the external circulation crystallization cooler (421), and the discharge port of the slurry mixed washing mother liquor pump (214) is connected to the cooling side inlet of the pressure sub-separator (423). The mother liquor outlet of the pressurized sub-separator (423) is connected to the inlet of the mother liquor receiver (429), the outlet of the mother liquor receiver (429) is connected to the suction port of the mother liquor discharge pump (430), the discharge port of the mother liquor discharge pump (430) is branched into two, one of which is connected to the heating side inlet of the mother liquor heater (431) and the other is further branched into two, which are respectively connected to the inlet of the isomerization reactor (432) and the heating side inlet of the cracking feed preheater (601), and the wash liquor outlet of the pressurized sub-separator (432) is connected to the inlet of the wash liquor receiver (424). The filter cake outlet is connected to the outlet of the condensation reaction liquid discharge pump (121) and the inlet of the crystal melter (426), the outlet of the crystal melter (426) is connected to the suction port of the circulation pump (427) of the crystal melter, the outlet of the circulation pump (427) of the crystal melter is branched into two, which are respectively connected to the inlet of the crystallization supply buffer tank (201) and the heating side inlet of the heater (428) of the crystal melter, and the heating side outlet of the heater (428) of the crystal melter is connected to the inlet of the crystal melter (426).

[0027] Apparatus for realizing the method for producing synthetic bisphenol A (5): The discharge port of the light fraction discharge pump (125) joins with the discharge port of the ethylbenzene supply pump (527) and is then connected to the heating side inlet of the dehydration tower preheater (501). The heating side outlet of the dehydration tower preheater (501) is connected to the inlet of the dehydration tower (502). The top outlet of the dehydration tower (502) is connected to the inlet of the acetone recovery tower (504). The top inlet is connected to the discharge port of the ethylbenzene discharge pump (515). The outlet of the tower pot is connected to the suction port of the dehydration tower pot discharge pump (518). The top outlet of the acetone recovery tower (504) is connected to the discharge port of the ethylbenzene discharge pump (515). The acetone tower condenser (506) is connected to the cooling side inlet, the top inlet is connected to the discharge port of the acetone tower reflux pump (509), the outlet of the kettle section is connected to the inlet of the phase separator (510), the gas phase outlet of the cooling side of the acetone tower condenser (506) is connected to the cooling side inlet of the acetone tower aftercooler (507), the liquid phase outlet is connected to the inlet of the acetone tower reflux tank (508), the gas phase outlet of the cooling side of the acetone tower aftercooler (507) is connected to the vacuum unit, the liquid phase outlet is connected to the inlet of the acetone tower reflux tank (508), the outlet of the acetone tower reflux tank (508) is connected to the acetone tower reflux pump (509). The outlet of the acetone column reflux pump (509) is connected to the suction port of the second-stage feed pump (110). The outlet of the phase separator (510) is connected to the suction port of the aqueous phase discharge pump (511) and the suction port of the ethylbenzene discharge pump (515). The outlet of the aqueous phase discharge pump (511) is connected to the cooling side inlet of the phenol-containing water cooler (512). The cooling side outlet of the phenol-containing water cooler (512) is connected to the cooling side inlet of the phenol-containing water cooler (513). The cooling side outlet of the phenol-containing water cooler (513) is connected to the inlet of the phase separator (514). The outlet of the phase separator (514) is connected to the inlet of the phase separator (510) and the suction port of the wastewater pump (516), respectively. The discharge port of the ethylbenzene discharge pump (515) is also connected to the cooling side inlet of the ethylbenzene cooler (517), the cooling side outlet of the ethylbenzene cooler (517) is connected to a vacuum unit. The outlet of the dehydration tower's boiler discharge pump (518) is connected to the inlet of the phenol recovery tower (519). The top outlet of the phenol recovery tower (519) is connected to the cooling side inlet of the phenol tower condenser (522), and the top inlet is connected to the discharge port of the reflux pump (525) of the phenol recovery tower.The outlet of the column bottom section is connected to the suction port of the column bottom discharge pump (521) of the phenol recovery column, the gas phase outlet on the cooling side of the phenol column condenser (522) is connected to the cooling side inlet of the phenol column aftercooler (523), the liquid phase outlet is connected to the inlet of the phenol column reflux tank (524), the gas phase outlet on the cooling side of the phenol column aftercooler (523) is connected to a vacuum unit, and the liquid phase outlet is connected to the inlet of the phenol column reflux tank (524).

[0028] Apparatus for implementing the synthetic bisphenol A production method (6): The discharge port of the mother liquor discharge pump (430) is connected to the heating side inlet of a cracking feed preheater (601), the heating side outlet of the cracking feed preheater (601) is connected to the inlet of a falling film evaporator (602), the outlet of the falling film evaporator (602) is connected to the inlet of a gas-liquid separation tank (603), the gas phase outlet of the gas-liquid separation tank (603) is connected to the inlet of a de-p-isopropylphenol column (604), the liquid phase outlet is connected to the inlet of a cracking reactor (610), and the de-p-isopropylphenol column (604) is connected to the inlet of a de-p-isopropylphenol column (604). The top outlet of the isopropylphenol column (604) is connected to the cooling side inlet of the condenser (607), the outlet of the column bottom is connected to the suction port of the column bottom discharge pump (606), the discharge port of the reflux pump (609) is branched into three, which are respectively connected to the top inlet of the de-p-isopropylphenol column (604), the inlet of the decomposition product tank (614), and the top inlet of the decomposition reactor (610), the gas phase outlet on the cooling side of the condenser (607) is connected to a vacuum unit, and the liquid phase outlet is connected to the inlet of the reflux tank (608), The outlet of the decomposition reactor (610) is connected to the inlet of the reflux pump (609), the top outlet of the decomposition reactor (610) is connected to the cooling side inlet of the decomposition product condenser (613), the outlet of the column pot is connected to the inlet of the decomposition reaction circulation pump (611), the discharge outlet of the decomposition reaction circulation pump (611) is branched into two, which are respectively connected to the heating side inlet of the decomposition reaction heater (612) and the incinerator, the heating side outlet of the decomposition reaction heater (612) is joined with the alkali catalyst and then connected to the column pot inlet of the decomposition reactor (610), The gas phase outlet of the cooling side is connected to a vacuum unit, the liquid phase outlet is connected to the inlet of a cracked product tank (614), the outlet of the cracked product tank (614) is connected to the suction port of a rearrangement supply pump (615), the suction port of the rearrangement supply pump (615) is connected to the cooling side inlet of a circulation cooler (616), the cooling side outlet of the circulation cooler (616) is branched into two, which are respectively connected to the inlet of the cracked product tank (614) and the inlet of a rearrangement reactor (617), and the outlet of the rearrangement reactor (617) is connected to the inlet of a mother liquor recovery tank (401).

[0029] The cooling-side outlet temperature of the first-stage cooler (101) is 65 to 70°C, the heating-side outlet temperature of the dehydration flash heater (106) is 85 to 87°C, the operating pressure of the dehydration flash evaporator (107) is 6 to 8 kPaA, the cooling-side outlet temperature of the second-stage cooler (111) is 70 to 75°C, the operating pressure of the first-stage pressurized main separator (207) is 300 to 550 kPaA, the operating pressure of the second-stage pressurized main separator (212) is 350 to 600 kPaA, the operating temperature of the high-pressure falling film evaporator (406) is 150 to 154°C and the operating pressure is 33 to 35 kPaA, the operating temperature of the low-pressure falling film evaporator (405) is 112 to 114°C and the operating pressure is 6 to 8 kPaA, and the inlet temperature of the isomerization reactor (432) is 70 to 75°C.

[0030] The present invention relates to a method and apparatus for producing synthetic bisphenol A using a resin method, which comprises a condensation reaction unit for catalytically condensing phenol and acetone to produce bisphenol A under the action of a resin catalyst, an adduct crystallization unit for mixing the condensation reaction concentrate with the recovered adduct crystals after melting and then crystallizing the adduct, a liquid-phase dephenolization unit for melting the adduct to obtain a bisphenol A product, a secondary adduct crystallization unit for recovering phenol and bisphenol A in the mother liquor, a solvent recovery unit for recovering unreacted phenol and acetone and sending the phenol-containing wastewater to a wastewater treatment plant, and a cracking and rearrangement unit for recovering phenol from the mother liquor, first cracking and rearranging bisphenol A and 2,4-bisphenol A therein, and then converting them into bisphenol A and returning the phenol to the system. In order to improve the yield and purity of phenol and reduce energy consumption, processes such as external circulation of the first-stage reactor, flash evaporation dehydration between the second-stage reactor, solid-liquid separation in a high-pressure separator, double-effect falling film evaporation and conversion in an isomerization reactor are introduced into the process. Through the application of these processes, the purity of the final bisphenol A product obtained is above 99.97 wt%, with free phenol less than 10 ppm, 2,4-bisphenol A less than 60 ppm, triphenols less than 25 ppm, and water less than 480 ppm. The consumption of standard oil per ton of bisphenol A product is less than 198 kg. [Effects of the Invention]

[0031] The advantages and benefits of the present invention are as follows: 1. The advantages of the synthetic bisphenol A production method and apparatus of the present invention are that a unique catalytic dehydration condensation reaction process is developed, which achieves a high conversion rate of acetone in one pass and high selectivity for bisphenol A production. It uses a series two-stage packed bed process, and the first stage reactor uses external circulation heat transfer, which reduces the average temperature in the reactor, inhibits the progress of reverse reaction, and improves the one-pass conversion rate. 2. The advantage of the method and apparatus for producing synthetic bisphenol A according to the present invention is that water can be removed in a timely manner before the second-stage reactor by using flash evaporation, thereby eliminating the chemical balance inhibiting effect of water on the condensation reaction for producing bisphenol A and the inhibitory effect of water on the activity of the resin catalyst in the condensation reaction, thereby achieving a higher one-pass conversion rate in the second-stage reactor. 3. The advantage of the synthetic bisphenol A production method and equipment of the present invention is that the main and sub-flows both use rotary drum type pressure centrifuges to carry out solid-liquid phase separation, which greatly improves the separation driving force and separation effect, thereby reducing the difficulty and energy consumption of removing and recovering phenol from the product in the subsequent areas. 4. The advantage of the synthetic bisphenol A production method and equipment of the present invention is that by applying thermal coupling technology and double-effect falling film evaporation technology, the steam consumption can be greatly reduced, and the steam consumption index is advanced. 5. The advantages of the method and apparatus for producing synthetic bisphenol A according to the present invention are that by-products are converted into bisphenol A using an isomerization reactor, the yield of bisphenol A is increased, the proportion of heavy components required for incineration is reduced, and pollution is reduced. [Brief explanation of the drawings]

[0032] [Figure 1] FIG. 1 is a block diagram of a method for synthesizing bisphenol A by a resin method. [Figure 2] FIG. 1 is a process diagram of condensation reaction unit 100#. [Figure 3] FIG. 10 is a process diagram of adduct crystallization unit 200#. [Figure 4] This is a process diagram of liquid phase dephenolation unit 300#. [Figure 5] FIG. 10 is a process diagram of secondary adduct crystallization unit 400#. [Figure 6] FIG. 10 is a process diagram of solvent recovery unit 500#. [Figure 7] FIG. 10 is a process diagram of decomposition and rearrangement unit 600#. DETAILED DESCRIPTION OF THE INVENTION

[0033] Example 1 Fresh acetone after purification, at a flow rate of 16,000 kg / h, was metered and fed proportionally to the first-stage reactor 102 and the second-stage reactor 112, respectively. The acetone fed to reactor 102 was mixed with recovered phenol from the cracking feed preheater 601 and materials from the first-stage circulation pump 105, entered the first-stage cooler 101, and was cooled to 65°C with circulating water before entering the first-stage reactors 102-104. A portion of the reaction liquid flowing out of the first-stage reactor 104 was circulated by the first-stage circulation pump 105 and returned to the first-stage reactor 102, with a circulation flow rate of 520,000 kg / h. The remainder was heated to 85°C by the dehydration flash heater 106 and then fed to the dehydration flash evaporator 107 to remove some of the water. The operating pressure of the flash evaporator was 6 kPaA. The flash vapor from the dehydration flash evaporator 107 is condensed and cooled by the flash evaporation first condenser 108 and the flash evaporation second condenser 109, and then the condensate containing water, acetone, and phenol flows into the light fraction receiving tank 124, and the tail gas is sent to the vacuum system. The dehydrated material from the dehydration flash evaporator 107 is mixed with recovered acetone and fresh acetone from the second stream, and then sent to the second stage cooler 111 by the second stage feed pump 110. After being cooled to 70°C with circulating water, it enters the second stage reactors 112 to 114. The condensation reaction liquid coming out of the second stage reactor 114 is mixed with the bottom liquid from the phenol absorption tower 306 and then passed through the adsorption The reaction mixture enters column 115, and is then heated by heat exchange with the bottom liquid of light fraction removal column 117 in preheater 116, after which it enters light fraction removal column 117. Water, unreacted acetone, and a portion of the phenol in the reaction mixture evaporate from the top of the column, and are condensed in condenser 122 and aftercooler 123. The tail gas enters the vacuum system, and the condensed liquid flows into light fraction receiving tank 124 and is sent to solvent recovery unit 500# by discharge pump 125 to recover phenol and acetone. The light fraction removal column reboiler 118 is heated with low-pressure steam, and the bottom product is concentrated and sent by discharge pump 119. It is then heat exchanged in preheater 116 to lower its temperature, and is sent to condensation reaction mixture receiving tank 120.

[0034] The reaction concentrate from the condensation reaction liquid discharge pump 121 and the recovered adduct crystal melt from the mother liquor recovery unit 400# of the crystal melting device circulation pump 427 are mixed in the crystallization supply buffer tank 201, then sent out by the crystallization supply pump 202, cooled by the supply cooler 203, and then enter the main circulation crystallizer 204. The crystal slurry is pumped out of the main circulation crystallizer 204 by the crystallization circulation pump 205, then enters the crystallization cooler 206, where the heat of crystallization is removed under the cooling effect of deionized water. The crystal slurry flowing out of the main circulation crystallizer 204 is continuously sent to the pressurized main separator 207 by the flow control valve to carry out solid-liquid separation. Phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump 214. The separated mother liquor and washing liquid enter the main separator mother liquor / washing liquid tank 208, and then washed. The phenol is introduced from the main separator and sent to the mother liquor receiving tank 401 by the discharge pump 218. The phenol from the phenol discharge pump 311 is mixed with the filtered adduct crystals in the slurry mixing and washing tank 210, and the mixed crystal slurries are sent to the second-stage pressurized main separator 212 by the corresponding crystal slurry pumps 211 for solid-liquid separation. The filtrate enters the slurry mixing centrifuge mother liquor tank 213 and is pumped out by the slurry mixing and washing mother liquor pump 214. It is then sent to the pressurized main separator 207 and the pressurized sub-separator 423, respectively, for phenol washing. The filter cake is removed by the centrifuge and sent to the crystal melter 215. The material in the crystal melter 215 is sent to the heater 217 by the corresponding crystal melt circulation pump 216 for heating, and then returned to the crystal melter 215. The operating pressures of the first-stage pressurized main separator 207 and the second-stage pressurized main separator 212 were 300 kPaA and 350 kPaA, respectively.

[0035] The adduct melt from the dephenolization feed pump 218 enters the falling film type dephenolization device 301, is evaporated by heating with steam, and enters the gas-liquid separation tank 302. The liquid phase enters the top of the steam stripping dephenolization device 305, the gas phase is condensed by the condenser 303, the tail gas enters the vacuum system, and the condensate enters the phenol tank 310. Fresh phenol with a flow rate of 48,864 kg / h from the tank area enters the fresh phenol tank 313 and is pumped out by the fresh phenol pump 314. A part of it is metered and sent to the phenol tank 310, and the rest is sent to the recovered phenol tank 416. The phenol in the phenol tank 310 is pumped out by the phenol discharge pump 311, cooled to a set value by the washing phenol cooler 312, and then sent to the slurry mixing washing tank 210 for washing. The water vapor is heated by an electric steam superheater 304 and enters the bottom of a steam stripping dephenolization unit 305 as steam stripping steam. The liquid bisphenol A obtained at the bottom is pumped by a BPA melt pump 315, molded, granulated, and packaged in a packaging machine 316 to obtain a bisphenol A product. The vapor from the top enters the bottom of a phenol absorber 306 and undergoes gas-liquid mass transfer with the absorbed phenol added from the top. The gas exiting the top enters a phenol absorber condenser 309, the tail gas enters a vacuum system, and the condensate, which is hydrous phenol, enters an ethylbenzene tank 526. The bottom liquid, a bisphenol A phenol solution, is sent to a cooler 308 by a phenol circulation pump 307 to be cooled and then returned to the top of the phenol absorber 306.

[0036] The material from the mother liquor receiving tank 401 is sent by the supply pump 402 to the first-stage supply preheater 403 and the second-stage supply preheater 404 in sequence. The first-stage supply preheater 403 is a thermally coupled heat exchanger, and the heat medium is the gas phase material from the third-stage gas-liquid separation tank 411. The second-stage supply preheater 404 is also a thermally coupled heat exchanger, and the heat medium is phenol from the recovery phenol pump 419. After the material has passed through two preheating stages, it is measured and divided into two parts. One part enters the high-pressure falling film evaporator 406, where it is evaporated by the heat of steam and emerges from the bottom of the high-pressure falling film evaporator 406. The outflowing gas and liquid phase materials enter the first stage gas-liquid separation tank 407, and the operating temperature and operating pressure of the high-pressure falling film evaporator 406 are 150°C and 33kPaA, respectively. The liquid phase material is pumped to the third stage gas-liquid separation tank 411 by the pump 410, and the gas phase material enters the low-pressure falling film evaporator 405 as a heat medium. After condensation, the gas and liquid phases are separated in the second stage gas-liquid separation tank 408, and the liquid phase enters the recovery phenol tank 416. The gas phase enters the tail gas condenser 409 and is further condensed by circulating water. The condensate enters the recovery phenol tank 416, and the tail gas condenser 409 is further condensed by circulating water. The remaining gas is sent to the vacuum system, and the remaining part of the preheated mother liquor is heated and evaporated in the low-pressure liquid falling film evaporator 405. The gas-liquid two-phase material flowing out from the bottom of the low-pressure liquid falling film evaporator 405 enters the third-stage gas-liquid separation tank 411. The operating temperature and operating pressure of the low-pressure liquid falling film evaporator 405 are 112°C and 6kPaA, respectively. Part of the gas phase material enters the feed preheater 403 as a heat medium, and the remaining part is condensed in the condenser 414 under the action of circulating water. The tail gases of the feed preheater 403 and the condenser 414 are combined and then enter the aftercooler 415, where the circulating water The tail gas is further condensed under the action of the vacuum system, and the condensate from the raw material preheater 403, the condenser 414 and the aftercooler 415 flows into the recovered phenol tank 416. The material in the recovered phenol tank 416 is pumped into the recovered phenol storage tank 418 by the phenol discharge pump 417, and then pumped out by the recovered phenol pump 419. After the temperature is lowered by heat exchange in the second-stage feed preheater 404 and the decomposition feed preheater 601, it is sent to the outlet of the first-stage cooler 101 of the condensation reactor and the phenol circulation pump 307, respectively.The liquid phase material in the third-stage gas-liquid separation tank 411 is a concentrated bisphenol A phenol solution, which is sent out by a crystallization feed pump 412, passed through a crystallization feed cooler 413, cooled with circulating water, and then enters a recovery crystallizer 420. The adduct crystal slurry is pumped out of the recovery crystallizer 420 by a crystallization circulation pump 422, then enters a crystallization cooler 421, where the heat of crystallization is cooled and removed with deionized water. The crystal slurry flowing out of the recovery crystallizer 420 is continuously sent to a pressure sub-separator 423 for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second-stage centrifuge of the slurry mixing washing mother liquor pump 214. The mother liquor separated from the pressure sub-separator 423 enters a mother liquor receiving tank 429, is sent out by a mother liquor discharge pump 430, is preheated by a mother liquor heater 431, and then part of it is sent to an isomerization reactor 432. The inlet temperature is 70°C, and part of the 2,4-bisphenol A, triphenol, chromanol, etc. is converted into bisphenol A before entering the mother liquor receiving tank 401, and the other part is sent to the cracking and rearrangement unit 600# for cracking and rearrangement. The wash liquid from the pressure secondary separator 423 enters the wash liquid receiving tank 424 and is sent to the mother liquor receiving tank 401 by the wash liquid discharge pump 425. A part of the reaction liquid introduced from the main separator and metered by the condensation reaction concentrated liquid discharge pump 121 is mixed with the filtered adduct crystals in the tail gas condenser 409. The material in the tail gas condenser 409 is sent to the heater 428 by the corresponding crystal melt circulation pump 427 to be heated and then returned to the tail gas condenser 409. The material in the tail gas condenser 409 is sent to the crystallization supply buffer tank 201 by the crystal melt circulation pump 427.

[0037] The dehydration tower 502 is an azeotropic distillation tower, and ethylbenzene is the azeotropic agent. The material from the light fraction discharge pump 121 is mixed with the material from the ethylbenzene feed pump 527 and then preheated by low-pressure steam in the dehydration tower feed preheater 501 before entering the dehydration tower 502. The overhead gas directly enters the acetone recovery tower 504, and the bottom liquid is phenol containing ethylbenzene, which is sent to the phenol recovery tower 519 by the tower pot discharge pump 518. The overhead gas from the acetone recovery tower 504 is condensed through the acetone tower condenser 506 and the aftercooler 507, and the tail gas is sent to the vacuum system. The condensate enters the acetone tower reflux tank 508 and is pumped out by the acetone tower reflux pump 509.One strand is sent to the top of the acetone recovery tower as reflux, and the other strand is sent to the suction port of the second-stage feed pump 110 of the condensation reaction unit 100# reactor as recovered acetone. The bottom product enters the phase separator 510 to form an aqueous phase and an organic phase. The aqueous phase material is pumped out by the aqueous phase discharge pump 511 and cooled by the coolers 512 and 513, then enters the phase separator 514 for further phase separation. The organic phase flows to the phase separator 510, and the aqueous phase is pumped out from the boundary region by the wastewater pump 516 as wastewater of this device for biochemical treatment. The organic phase of the phase separator 510 is pumped out by the ethylbenzene discharge pump 515, a portion of which is returned to the top of the dehydration tower 502 as reflux liquid. The remainder is cooled by the ethylbenzene cooler 517 and then enters the vacuum pump as the auxiliary working fluid of the ethylbenzene liquid ring vacuum pump. By adjusting the heating steam flow rate of the reboiler 505, the rising The amount of steam is controlled, and the material from the column bottom discharge pump 518 of the dehydration column 502 enters the phenol recovery column 519. The overhead gas is condensed through the phenol column condenser 522 and the aftercooler 523. The tail gas enters the vacuum system, and the condensate enters the reflux tank 524. A portion is returned to the top of the column as reflux by the reflux pump 525. The remainder overflows into the ethylbenzene tank 526. The ethylbenzene tank 526 receives hydrous phenol from the phenol absorption column condenser 309, replaced ethylbenzene from the vacuum system, and make-up ethylbenzene. The material in the ethylbenzene tank 526 is sent to the dehydration column 502 via the ethylbenzene supply pump 527. The column bottom liquid is phenol without ethylbenzene, and is sent to the recovered phenol storage tank 416 by the column bottom discharge pump 521. The amount of steam rising in the column is controlled by adjusting the heating steam flow rate of the reboiler 520.

[0038] The mother liquor from the mother liquor discharge pump 430 is preheated by the cracking feed preheater 601 and then enters the falling film evaporator 602. The cracking feed preheater 601 is a thermally coupled heat exchanger, and the heat medium is the recovered phenol from the second-stage feed preheater 404. The mother liquor is evaporated by heating with steam in the falling film evaporator 602, and the gas-liquid two-phase substance enters the gas-liquid separation tank 603. The liquid phase enters the column pot of the cracking reactor 610, and the gas phase enters the p-isopropylphenol removal column 604, where the p-isopropylphenol removal column The bottom liquid of the p-isopropylphenol column 604 is a heavy fraction containing p-isopropylphenol, and is discharged to the outside of the system via a discharge pump 606 and incinerated. The overhead gas is condensed and cooled by a condenser 607, the tail gas enters a vacuum system, and the condensate enters a reflux tank 608 and is then pumped out by a reflux pump 609. A portion of the condensate is returned to the top of the column as reflux for the p-isopropylphenol removal column 604, and the other portion is returned to the top of the decomposition reactor 610 as reflux for the decomposition reactor 610. The material that enters the top and overflows from the reflux tank 608 enters the decomposition product tank 614, and by adjusting the flow rate of the heated steam in the reboiler 605, the amount of steam rising in the column is controlled. The material from the gas-liquid separation tank 603 enters the decomposition reactor 610, and is then sent to the decomposition reactor heater 612 by the decomposition reaction circulation pump 611 to heat the material. After that, a certain amount of alkaline solution is added as a catalyst for the decomposition reaction, and the material is returned to the decomposition reactor 610. Tar was discharged outside the system via a cracking reaction circulation pump 611 and incinerated, the overhead gas from the cracking reactor 610 was condensed and cooled in a cracking product condenser 613, the tail gas entered a vacuum system, and the condensate entered a cracking product tank 614 and was then sent to a circulation cooler 616 by a rearrangement reaction feed pump 615 where it was cooled. A portion of the condensate was circulated back to the cracking product tank 614, while the other portion was used as a feed for a rearrangement reactor 617, and the rearranged material was returned to the mother liquor receiving tank 401.

[0039] The purity of the final bisphenol A product is over 99.97 wt%, with free phenol less than 10 ppm, 2,4-bisphenol A less than 60 ppm, triphenols less than 25 ppm, and water less than 480 ppm, and the consumption of standard oil per tonne of bisphenol A product is less than 193 kg.

[0040] Example 2 Fresh acetone after purification, at a flow rate of 15,000 kg / h, was metered and fed proportionally to the first-stage reactor 102 and the second-stage reactor 112, respectively. The acetone fed to reactor 102 was mixed with recovered phenol from the cracking feed preheater 601 and the material from the first-stage circulation pump 105, entered the first-stage cooler 101, and was cooled to 67°C by circulating water before entering the first-stage reactors 102 to 104. A portion of the reaction liquid flowing out of the first-stage reactor 104 was circulated by the first-stage circulation pump 105 and returned to the first-stage reactor 102, with a circulation flow rate of 487,500 kg / h. The remainder was heated to 86°C by the dehydration flash heater 106 and then fed to the dehydration flash evaporator 107 to remove some of the water. The operating pressure of the flash evaporator was 7 kPaA. The flash vapor from the dehydration flash evaporator 107 is condensed and cooled by the flash evaporation first condenser 108 and the flash evaporation second condenser 109, and the condensate containing water, acetone, and phenol flows into the light fraction receiving tank 124, and the tail gas is sent to the vacuum system. The dehydrated material from the dehydration flash evaporator 107 is mixed with recovered acetone and fresh acetone from the second stream, and then sent to the second stage cooler 111 by the second stage feed pump 110. It is cooled to 72°C with circulating water and then enters the second stage reactors 112 to 114. The condensation reaction liquid coming out of the second stage reactor 114 is mixed with the bottom liquid from the phenol absorption tower 306 and then passed through the adsorption The reaction mixture enters column 115, and is then heated by heat exchange with the bottom liquid of light fraction removal column 117 in preheater 116, after which it enters light fraction removal column 117. Water, unreacted acetone, and a portion of the phenol in the reaction mixture evaporate from the top of the column, and are condensed in condenser 122 and aftercooler 123. The tail gas enters the vacuum system, and the condensed liquid flows into light fraction receiving tank 124 and is sent to solvent recovery unit 500# by discharge pump 125 to recover phenol and acetone. The light fraction removal column reboiler 118 is heated with low-pressure steam, and the bottom product is concentrated and sent by discharge pump 119. It is then heat exchanged in preheater 116 to lower its temperature, and is sent to condensation reaction mixture receiving tank 120.

[0041] The reaction concentrate from the condensation reaction liquid discharge pump 121 and the recovered adduct crystal melt from the mother liquor recovery unit 400# of the crystal melting device circulation pump 427 are mixed in the crystallization supply buffer tank 201, then sent out by the crystallization supply pump 202, cooled by the supply cooler 203, and then enter the main circulation crystallizer 204. The crystal slurry is pumped out of the main circulation crystallizer 204 by the crystallization circulation pump 205, then enters the crystallization cooler 206, where the heat of crystallization is removed under the cooling effect of deionized water. The crystal slurry flowing out of the main circulation crystallizer 204 is continuously sent to the pressurized main separator 207 by the flow control valve to carry out solid-liquid separation. Phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump 214. The separated mother liquor and washing liquid enter the main separator mother liquor / washing liquid tank 208, and then washed. The phenol is introduced from the main separator and sent to the mother liquor receiving tank 401 by the discharge pump 218. The phenol from the phenol discharge pump 311 is mixed with the filtered adduct crystals in the slurry mixing and washing tank 210, and the mixed crystal slurries are sent to the second-stage pressurized main separator 212 by the corresponding crystal slurry pumps 211 for solid-liquid separation. The filtrate enters the slurry mixing centrifuge mother liquor tank 213 and is pumped out by the slurry mixing and washing mother liquor pump 214. It is then sent to the pressurized main separator 207 and the pressurized sub-separator 423, respectively, for phenol washing. The filter cake is removed by the centrifuge and sent to the crystal melter 215. The material in the crystal melter 215 is sent to the heater 217 by the corresponding crystal melt circulation pump 216 for heating, and then returned to the crystal melter 215. The operating pressures of the first-stage pressurized main separator 207 and the second-stage pressurized main separator 212 were 450 kPaA and 500 kPaA, respectively.

[0042] The adduct melt from the dephenolization feed pump 218 enters the falling film type dephenolization device 301, is evaporated by heating with steam, and enters the gas-liquid separation tank 302. The liquid phase enters the top of the steam stripping dephenolization device 305, the gas phase is condensed by the condenser 303, the tail gas enters the vacuum system, and the condensate enters the phenol tank 310. Fresh phenol with a flow rate of 45,810 kg / h from the tank area enters the fresh phenol tank 313 and is pumped out by the fresh phenol pump 314. A part of it is metered and sent to the phenol tank 310, and the rest is sent to the recovered phenol tank 416. The phenol in the phenol tank 310 is pumped out by the phenol discharge pump 311, cooled to a set value by the washing phenol cooler 312, and then sent to the slurry mixing washing tank 210 for washing. The water vapor is heated by an electric steam superheater 304 and enters the bottom of a steam stripping dephenolization unit 305 as steam stripping steam. The liquid bisphenol A obtained at the bottom is pumped by a BPA melt pump 315, molded, granulated, and packaged in a packaging machine 316 to obtain a bisphenol A product. The vapor from the top enters the bottom of a phenol absorber 306 and undergoes gas-liquid mass transfer with the absorbed phenol added from the top. The gas exiting the top enters a phenol absorber condenser 309, the tail gas enters a vacuum system, and the condensate, which is hydrous phenol, enters an ethylbenzene tank 526. The bottom liquid, a bisphenol A phenol solution, is sent to a cooler 308 by a phenol circulation pump 307 to be cooled and then returned to the top of the phenol absorber 306.

[0043] The material from the mother liquor receiving tank 401 is sent by the supply pump 402 to the first-stage supply preheater 403 and the second-stage supply preheater 404 in sequence. The first-stage preheater 403 is a thermally coupled heat exchanger, and the heat medium is the gas phase material from the third-stage gas-liquid separation tank 411. The second-stage supply preheater 404 is also a thermally coupled heat exchanger, and the heat medium is phenol from the recovery phenol pump 419. After the two-stage preheating, the material is metered and divided into two parts. One part enters the high-pressure falling film evaporator 406, where it is evaporated by the heat of steam and flows out from the bottom of the high-pressure falling film evaporator 406. The gas and liquid phase materials enter the first-stage gas-liquid separation tank 407, and the operating temperature and pressure of the high-pressure falling film evaporator 406 are 152°C and 34kPaA, respectively. The liquid phase material is pumped to the third-stage gas-liquid separation tank 411 by the pump 410. The gas phase material enters the low-pressure falling film evaporator 405 as a heat medium. After condensation, the gas and liquid phases are separated in the second-stage gas-liquid separation tank 408. The liquid phase enters the recovery phenol tank 416, and the gas phase enters the tail gas condenser 409, where it is further condensed by circulating water. The condensate enters the recovery phenol tank 416, and the tail gas is passed through the vacuum system. The other part of the preheated mother liquor is heated and evaporated in the low-pressure falling film evaporator 405. The gas-liquid two-phase material flowing out from the bottom of the low-pressure falling film evaporator 405 enters the third-stage gas-liquid separation tank 411. The operating temperature and operating pressure of the low-pressure falling film evaporator 405 are 113°C and 7kPaA, respectively. Part of the gas phase material enters the first-stage feed preheater 403 as a heat medium, and the remaining part is condensed in the condenser 414 under the action of circulating water. The tail gases of the first-stage feed preheater 403 and condenser 414 are combined and then enter the aftercooler 415, where the circulating water The condensate is further condensed under the action, and the tail gas is sent to the vacuum system. The condensate of the first-stage supply preheater 403, the condenser 414 and the aftercooler 415 flows into the recovered phenol tank 416. The material in the recovered phenol tank 416 is sent to the recovered phenol storage tank 418 by the phenol discharge pump 417, and then sent out by the recovered phenol pump 419. After the temperature is lowered by the heat exchange of the second-stage supply preheater 404 and the decomposition supply preheater 601, it is sent to the outlet of the first-stage cooler 101 of the condensation reactor and the outlet of the phenol circulation pump 307, respectively.The liquid phase material in the third-stage gas-liquid separation tank 411 is a concentrated bisphenol A phenol solution, which is sent out by a crystallization feed pump 412, passed through a crystallization feed cooler 413, cooled with circulating water, and then enters a recovery crystallizer 420. The adduct crystal slurry is pumped out of the recovery crystallizer 420 by a crystallization circulation pump 422, then enters a crystallization cooler 421, where the heat of crystallization is cooled and removed with deionized water. The crystal slurry flowing out of the recovery crystallizer 420 is continuously sent to a pressure sub-separator 423 for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second-stage centrifuge of the slurry mixing washing mother liquor pump 214. The mother liquor separated from the pressure sub-separator 423 enters a mother liquor receiving tank 429, is sent out by a mother liquor discharge pump 430, is preheated by a mother liquor heater 431, and then part of it is sent to an isomerization reactor 432. The inlet temperature is 72°C, and part of the 2,4-bisphenol A, triphenol, chromanol, etc. is converted into bisphenol A before entering the mother liquor receiving tank 401, and the other part is sent to the cracking and rearrangement unit 600# for cracking and rearrangement. The wash liquid from the pressure secondary separator 423 enters the wash liquid receiving tank 424 and is sent to the mother liquor receiving tank 401 by the wash liquid discharge pump 425. A part of the reaction liquid introduced from the main separator and metered by the condensation reaction concentrated liquid discharge pump 121 is mixed with the filtered adduct crystals in the tail gas condenser 409. The material in the tail gas condenser 409 is sent to the heater 428 by the corresponding crystal melt circulation pump 427 to be heated and then returned to the tail gas condenser 409. The material in the tail gas condenser 409 is sent to the crystallization supply buffer tank 201 by the crystal melt circulation pump 427.

[0044] The dehydration tower 502 is an azeotropic distillation tower, and ethylbenzene is the azeotropic agent. The material from the light fraction discharge pump 121 is mixed with the material from the ethylbenzene feed pump 527 and then preheated by low-pressure steam in the dehydration tower feed preheater 501 before entering the dehydration tower 502. The overhead gas directly enters the acetone recovery tower 504, and the bottom liquid is phenol containing ethylbenzene, which is sent to the phenol recovery tower 519 by the tower pot discharge pump 518. The overhead gas from the acetone recovery tower 504 is condensed through the acetone tower condenser 506 and the aftercooler 507, and the tail gas is sent to the vacuum system. The condensate enters the acetone tower reflux tank 508 and is pumped out by the acetone tower reflux pump 509.One strand is sent to the top of the acetone recovery tower as reflux, and the other strand is sent to the suction port of the second-stage feed pump 110 of the condensation reaction unit 100# reactor as recovered acetone. The bottom product enters the phase separator 510 to form an aqueous phase and an organic phase. The aqueous phase material is pumped out by the aqueous phase discharge pump 511 and cooled by the coolers 512 and 513, then enters the phase separator 514 for further phase separation. The organic phase flows to the phase separator 510, and the aqueous phase is pumped out from the boundary region by the wastewater pump 516 as wastewater of this device for biochemical treatment. The organic phase of the phase separator 510 is pumped out by the ethylbenzene discharge pump 515, a portion of which is returned to the top of the dehydration tower 502 as reflux liquid. The remainder is cooled by the ethylbenzene cooler 517 and then enters the vacuum pump as the auxiliary working fluid of the ethylbenzene liquid ring vacuum pump. By adjusting the heating steam flow rate of the reboiler 505, the rising The amount of steam is controlled, and the material from the column bottom discharge pump 518 of the dehydration column 502 enters the phenol recovery column 519. The overhead gas is condensed through the phenol column condenser 522 and the aftercooler 523. The tail gas enters the vacuum system, and the condensate enters the reflux tank 524. A portion is returned to the top of the column as reflux by the reflux pump 525. The remainder overflows into the ethylbenzene tank 526. The ethylbenzene tank 526 receives hydrous phenol from the phenol absorption column condenser 309, replaced ethylbenzene from the vacuum system, and make-up ethylbenzene. The material in the ethylbenzene tank 526 is sent to the dehydration column 502 via the ethylbenzene supply pump 527. The column bottom liquid is phenol without ethylbenzene, and is sent to the recovered phenol storage tank 416 by the column bottom discharge pump 521. The amount of steam rising in the column is controlled by adjusting the heating steam flow rate of the reboiler 520.

[0045] The mother liquor from the mother liquor discharge pump 430 is preheated by the cracking feed preheater 601 and then enters the falling film evaporator 602. The cracking feed preheater 601 is a thermally coupled heat exchanger, and the heat medium is the recovered phenol from the second-stage feed preheater 404. The mother liquor is evaporated by heating with steam in the falling film evaporator 602, and the gas-liquid two-phase substance enters the gas-liquid separation tank 603. The liquid phase enters the column pot of the cracking reactor 610, and the gas phase enters the p-isopropylphenol removal column 604, where the p-isopropylphenol removal column The bottom liquid of the p-isopropylphenol column 604 is a heavy fraction containing p-isopropylphenol, and is discharged to the outside of the system via a discharge pump 606 and incinerated. The overhead gas is condensed and cooled by a condenser 607, the tail gas enters a vacuum system, and the condensate enters a reflux tank 608 and is then pumped out by a reflux pump 609. A portion of the condensate is returned to the top of the column as reflux for the p-isopropylphenol removal column 604, and the other portion is returned to the top of the decomposition reactor 610 as reflux for the decomposition reactor 610. The material that enters the top and overflows from the reflux tank 608 enters the decomposition product tank 614, and by adjusting the flow rate of the heated steam in the reboiler 605, the amount of steam rising in the column is controlled. The material from the gas-liquid separation tank 603 enters the decomposition reactor 610, and is then sent to the decomposition reactor heater 612 by the decomposition reaction circulation pump 611 to heat the material. After that, a certain amount of alkaline solution is added as a catalyst for the decomposition reaction, and the material is returned to the decomposition reactor 610. Tar was discharged outside the system via a cracking reaction circulation pump 611 and incinerated, the overhead gas from the cracking reactor 610 was condensed and cooled in a cracking product condenser 613, the tail gas entered a vacuum system, and the condensate entered a cracking product tank 614 and was then sent to a circulation cooler 616 by a rearrangement reaction feed pump 615 where it was cooled. A portion of the condensate was circulated back to the cracking product tank 614, while the other portion was used as a feed for a rearrangement reactor 617, and the rearranged material was returned to the mother liquor receiving tank 401.

[0046] The purity of the final bisphenol A product is over 99.97 wt%, with free phenol less than 10 ppm, 2,4-bisphenol A less than 60 ppm, triphenols less than 25 ppm, and water less than 480 ppm, and the consumption of standard oil per tonne of bisphenol A product is less than 196 kg.

[0047] Example 3 Fresh acetone after purification, at a flow rate of 14,000 kg / h, was metered and fed proportionally to the first-stage reactor 102 and the second-stage reactor 112, respectively. The acetone fed to reactor 102 was mixed with recovered phenol from the cracking feed preheater 601 and materials from the first-stage circulation pump 105, entered the first-stage cooler 101, and was cooled to 70°C with circulating water before entering the first-stage reactors 102-104. A portion of the reaction liquid flowing out of the first-stage reactor 104 was circulated by the first-stage circulation pump 105 and returned to the first-stage reactor 102, with a circulation flow rate of 520,000 kg / h. The remainder was heated to 87°C by the dehydration flash heater 106 and then fed to the dehydration flash evaporator 107 to remove some of the water. The operating pressure of the flash evaporator was 8 kPaA. The flash vapor from the dehydration flash evaporator 107 is condensed and cooled by the flash evaporation first condenser 108 and the flash evaporation second condenser 109, and then the condensate containing water, acetone, and phenol flows into the light fraction receiving tank 124, and the tail gas is sent to the vacuum system. The dehydrated material from the dehydration flash evaporator 107 is mixed with recovered acetone and fresh acetone from the second stream, and then sent to the second stage cooler 111 by the second stage feed pump 110. After being cooled to 75°C with circulating water, it enters the second stage reactors 112 to 114. The condensation reaction liquid coming out of the second stage reactor 114 is mixed with the bottom liquid from the phenol absorption tower 306 and then passed through the adsorption The reaction mixture enters column 115, and is then heated by heat exchange with the bottom liquid of light fraction removal column 117 in preheater 116, after which it enters light fraction removal column 117. Water, unreacted acetone, and a portion of the phenol in the reaction mixture evaporate from the top of the column, and are condensed in condenser 122 and aftercooler 123. The tail gas enters the vacuum system, and the condensed liquid flows into light fraction receiving tank 124 and is sent to solvent recovery unit 500# by discharge pump 125 to recover phenol and acetone. The light fraction removal column reboiler 118 is heated with low-pressure steam, and the bottom product is concentrated and sent by discharge pump 119. It is then heat exchanged in preheater 116 to lower its temperature, and is sent to condensation reaction mixture receiving tank 120.

[0048] The reaction concentrate from the condensation reaction liquid discharge pump 121 and the recovered adduct crystal melt from the mother liquor recovery unit 400# of the crystal melting device circulation pump 427 are mixed in the crystallization supply buffer tank 201, then sent out by the crystallization supply pump 202, cooled by the supply cooler 203, and then enter the main circulation crystallizer 204. The crystal slurry is pumped out of the main circulation crystallizer 204 by the crystallization circulation pump 205, then enters the crystallization cooler 206, where the heat of crystallization is removed under the cooling effect of deionized water. The crystal slurry flowing out of the main circulation crystallizer 204 is continuously sent to the pressurized main separator 207 by the flow control valve to carry out solid-liquid separation. Phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump 214. The separated mother liquor and washing liquid enter the main separator mother liquor / washing liquid tank 208, and then washed. The phenol is introduced from the main separator and sent to the mother liquor receiving tank 401 by the discharge pump 218. The phenol from the phenol discharge pump 311 is mixed with the filtered adduct crystals in the slurry mixing and washing tank 210, and the mixed crystal slurries are sent to the second-stage pressurized main separator 212 by the corresponding crystal slurry pumps 211 for solid-liquid separation. The filtrate enters the slurry mixing centrifuge mother liquor tank 213 and is pumped out by the slurry mixing and washing mother liquor pump 214. It is then sent to the pressurized main separator 207 and the pressurized sub-separator 423, respectively, for phenol washing. The filter cake is removed by the centrifuge and sent to the crystal melter 215. The material in the crystal melter 215 is sent to the heater 217 by the corresponding crystal melt circulation pump 216 for heating, and then returned to the crystal melter 215. The operating pressures of the first-stage pressurized main separator 207 and the second-stage pressurized main separator 212 were 550 kPaA and 600 kPaA, respectively.

[0049] The adduct melt from the dephenolization feed pump 218 enters the falling film type dephenolization device 301, is evaporated by heating with steam, and enters the gas-liquid separation tank 302. The liquid phase enters the top of the steam stripping dephenolization device 305, the gas phase is condensed by the condenser 303, the tail gas enters the vacuum system, and the condensate enters the phenol tank 310. Fresh phenol with a flow rate of 442,756 kg / h from the tank area enters the fresh phenol tank 313 and is pumped out by the fresh phenol pump 314. A part of it is metered and sent to the phenol tank 310, and the rest is sent to the recovered phenol tank 416. The phenol in the phenol tank 310 is pumped out by the phenol discharge pump 311, cooled to a set value by the washing phenol cooler 312, and then sent to the slurry mixing washing tank 210 for washing. The water vapor is heated by an electric steam superheater 304 and enters the bottom of a steam stripping dephenolization unit 305 as steam stripping steam. The liquid bisphenol A obtained at the bottom is pumped by a BPA melt pump 315, molded, granulated, and packaged in a packaging machine 316 to obtain a bisphenol A product. The vapor from the top enters the bottom of a phenol absorber 306 and undergoes gas-liquid mass transfer with the absorbed phenol added from the top. The gas exiting the top enters a phenol absorber condenser 309, the tail gas enters a vacuum system, and the condensate, which is hydrous phenol, enters an ethylbenzene tank 526. The bottom liquid, a bisphenol A phenol solution, is sent to a cooler 308 by a phenol circulation pump 307 to be cooled and then returned to the top of the phenol absorber 306.

[0050] The material from the mother liquor receiving tank 401 is sent by the supply pump 402 to the first-stage supply preheater 403 and the second-stage supply preheater 404 in sequence. The first-stage supply preheater 403 is a thermally coupled heat exchanger, and the heat medium is the gas phase material from the third-stage gas-liquid separation tank 411. The second-stage supply preheater 404 is also a thermally coupled heat exchanger, and the heat medium is phenol from the recovery phenol pump 419. After the material has been preheated in two stages, it is measured and divided into two parts. One part enters the high-pressure falling film evaporator 406, where it is evaporated by the heat of steam and flows out from the bottom of the high-pressure falling film evaporator 406. The gas and liquid phase materials enter the first-stage gas-liquid separation tank 407, and the operating temperature and pressure of the high-pressure falling film evaporator 406 are 154°C and 35kPaA, respectively. The liquid phase material is pumped into the gas-liquid separation tank 411 by the pump 410, and the gas phase material enters the low-pressure falling film evaporator 405 as a heat medium. After condensation, the gas and liquid phases are separated in the second-stage gas-liquid separation tank 408, and the liquid phase enters the recovery phenol tank 416. The gas phase enters the tail gas condenser 409 and is further condensed by circulating water. The condensate enters the recovery phenol tank 416, and the tail gas is passed through the vacuum system. The other part of the preheated mother liquor is heated and evaporated in the low-pressure liquid falling film evaporator 405, and the gas-liquid two-phase material flowing out from the bottom of the low-pressure liquid falling film evaporator 405 enters the third-stage gas-liquid separation tank 411. The operating temperature and operating pressure of the low-pressure liquid falling film evaporator 405 are 114°C and 8kPaA, respectively. A part of the gas phase material enters the first-stage supply preheater 403 as a heat medium, and the remaining part is condensed in the condenser 414 under the action of circulating water. The tail gases of the first-stage supply preheater 403 and condenser 414 are combined and then enter the aftercooler 415, where the action of circulating water is used. The condensate from the first-stage feed preheater 403, the condenser 414 and the aftercooler 415 flows into the recovered phenol tank 416. The material in the recovered phenol tank 416 is pumped into the recovered phenol storage tank 418 by the phenol discharge pump 417, and then pumped out by the recovered phenol pump 419. After the temperature is lowered by heat exchange in the second-stage feed preheater 404 and the decomposition feed preheater 601, the material is sent to the outlet of the first-stage cooler 101 of the condensation reactor and the phenol circulation pump 307, respectively.The liquid phase material in the third-stage gas-liquid separation tank 411 is a concentrated bisphenol A phenol solution, which is sent out by the crystallization supply pump 412 and cooled with circulating water via the crystallization feed cooler 413 before entering the recovery crystallizer 420. The adduct crystal slurry is pumped out of the recovery crystallizer 420 by the crystallization circulation pump 422 and then enters the crystallization cooler 421, where the heat of crystallization is cooled and removed with deionized water. The crystal slurry flowing out of the recovery crystallizer 420 is continuously sent to the pressure sub-separator 423 for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second-stage centrifuge of the slurry mixing washing mother liquor pump 214. The mother liquor separated from the pressure sub-separator 423 enters the mother liquor receiving tank 429 and is sent out by the mother liquor discharge pump 430. After being preheated by the mother liquor heater 431, a portion of it is subjected to the isomerization reaction. The 2,4-bisphenol A, triphenol, chromanol, etc. are partially converted into bisphenol A and then sent to the mother liquor receiving tank 401, and the remaining portion is sent to the decomposition and rearrangement unit 600# for decomposition and rearrangement. The washing liquid from the pressure secondary separator 423 enters the washing liquid receiving tank 424 and is sent to the mother liquor receiving tank 401 by the washing liquid discharge pump 425. A portion of the reaction liquid introduced from the main separator and metered by the condensation reaction concentrated liquid discharge pump 121 is mixed with the filtered adduct crystals in the crystal melting device 426. The material in the crystal melting device 426 is sent to the heater 428 by the corresponding crystal melting circulation pump 427 to be heated and then returned to the crystal melting device 426. The material in the crystal melting device 426 is sent to the crystallization supply buffer tank 201 by the crystal melting circulation pump 427.

[0051] The dehydration tower 502 is an azeotropic distillation tower, and ethylbenzene is the azeotropic agent. The material from the light fraction discharge pump 121 is mixed with the material from the ethylbenzene feed pump 527 and then preheated by low-pressure steam in the dehydration tower feed preheater 501 before entering the dehydration tower 502. The overhead gas directly enters the acetone recovery tower 504, and the bottom liquid is phenol containing ethylbenzene, which is sent to the phenol recovery tower 519 by the tower pot discharge pump 518. The overhead gas from the acetone recovery tower 504 is condensed through the acetone tower condenser 506 and the aftercooler 507, and the tail gas is sent to the vacuum system. The condensate enters the acetone tower reflux tank 508 and is pumped out by the acetone tower reflux pump 509.One strand is sent to the top of the acetone recovery tower as reflux, and the other strand is sent to the suction port of the second-stage feed pump 110 of the condensation reaction unit 100# reactor as recovered acetone. The bottom product enters the phase separator 510 to form an aqueous phase and an organic phase. The aqueous phase material is pumped out by the aqueous phase discharge pump 511 and cooled by the coolers 512 and 513, then enters the phase separator 514 for further phase separation. The organic phase flows to the phase separator 510, and the aqueous phase is pumped out from the boundary region by the wastewater pump 516 as wastewater of this device for biochemical treatment. The organic phase of the phase separator 510 is pumped out by the ethylbenzene discharge pump 515, a portion of which is returned to the top of the dehydration tower 502 as reflux liquid. The remainder is cooled by the ethylbenzene cooler 517 and then enters the vacuum pump as the auxiliary working fluid of the ethylbenzene liquid ring vacuum pump. By adjusting the heating steam flow rate of the reboiler 505, the rising The amount of steam is controlled, and the material from the column bottom discharge pump 518 of the dehydration column 502 enters the phenol recovery column 519. The overhead gas is condensed through the phenol column condenser 522 and the aftercooler 523. The tail gas enters the vacuum system, and the condensate enters the reflux tank 524. A portion is returned to the top of the column as reflux by the reflux pump 525. The remainder overflows into the ethylbenzene tank 526. The ethylbenzene tank 526 receives hydrous phenol from the phenol absorption column condenser 309, replaced ethylbenzene from the vacuum system, and make-up ethylbenzene. The material in the ethylbenzene tank 526 is sent to the dehydration column 502 via the ethylbenzene supply pump 527. The column bottom liquid is phenol without ethylbenzene, and is sent to the recovered phenol storage tank 416 by the column bottom discharge pump 521. The amount of steam rising in the column is controlled by adjusting the heating steam flow rate of the reboiler 520.

[0052] The mother liquor from the mother liquor discharge pump 430 is preheated by the cracking feed preheater 601 and then enters the falling film evaporator 602. The cracking feed preheater 601 is a thermally coupled heat exchanger, and the heat medium is the recovered phenol from the second-stage feed preheater 404. The mother liquor is evaporated by heating with steam in the falling film evaporator 602, and the gas-liquid two-phase substance enters the gas-liquid separation tank 603. The liquid phase enters the column pot of the cracking reactor 610, and the gas phase enters the p-isopropylphenol removal column 604, where the p-isopropylphenol removal column The bottom liquid of the p-isopropylphenol column 604 is a heavy fraction containing p-isopropylphenol, and is discharged to the outside of the system via a discharge pump 606 and incinerated. The overhead gas is condensed and cooled by a condenser 607, the tail gas enters a vacuum system, and the condensate enters a reflux tank 608 and is then pumped out by a reflux pump 609. A portion of the condensate is returned to the top of the column as reflux for the p-isopropylphenol removal column 604, and the other portion is returned to the top of the decomposition reactor 610 as reflux for the decomposition reactor 610. The material that enters the top and overflows from the reflux tank 608 enters the decomposition product tank 614, and by adjusting the flow rate of the heated steam in the reboiler 605, the amount of steam rising in the column is controlled. The material from the gas-liquid separation tank 603 enters the decomposition reactor 610, and is then sent to the decomposition reactor heater 612 by the decomposition reaction circulation pump 611 to heat the material. After that, a certain amount of alkaline solution is added as a catalyst for the decomposition reaction, and the material is returned to the decomposition reactor 610. Tar was discharged outside the system via a cracking reaction circulation pump 611 and incinerated, the overhead gas from the cracking reactor 610 was condensed and cooled in a cracking product condenser 613, the tail gas entered a vacuum system, and the condensate entered a cracking product tank 614 and was then sent to a circulation cooler 616 by a rearrangement reaction feed pump 615 where it was cooled. A portion of the condensate was circulated back to the cracking product tank 614, while the other portion was used as a feed for a rearrangement reactor 617, and the rearranged material was returned to the mother liquor receiving tank 401.

[0053] The purity of the final bisphenol A product is more than 99.97 wt%, with free phenol less than 10 ppm, 2,4-bisphenol A less than 60 ppm, triphenols less than 25 ppm, and water less than 480 ppm, and the consumption of standard oil per tonne of bisphenol A product is less than 195 kg.

[0054] The technical means disclosed and proposed by the present invention can be achieved by those skilled in the art by referring to the contents of this specification and appropriately changing the conditions, etc. Although the method and manufacturing technology of the present invention have been described through preferred embodiments, those skilled in the art can obviously modify or combine the methods and technical means described herein to achieve the final manufacturing technology without departing from the content, spirit, and scope of the present invention. It should be noted that all similar substitutions and modifications will be apparent to those skilled in the art, and such substitutions and modifications are deemed to be within the spirit, scope, and content of the present invention. [Explanation of symbols]

[0055] 101 First stage cooler 102 First stage reactor 103 First stage reactor 104 First stage reactor 105 First stage circulation pump 106 Dehydration flash evaporative heater 107 Dehydration flash evaporator 108 Flash evaporation primary condenser 109 Flash evaporation secondary condenser 110 Second stage supply pump 111 Second stage cooler 112 Second stage reactor 113 Second stage reactor 114 Second stage reactor 115 Adsorption Column 116 Light fraction removal column supply preheater 117 Light fraction removal tower 118 Light fraction removal column reboiler 119 Light fraction removal column kettle discharge pump 120 Condensation reaction liquid receiving tank 121 Condensation reaction concentrated liquid discharge pump 122 Light fraction removal column condenser 123 Light fraction removal tower aftercooler 124 Light separation tank 201 Crystallization feed buffer tank 202 Main crystallizer feed pump 203 Main Crystallizer Feed Cooler 204 Main circulation type crystallizer 205 Crystallization Circulation Pump 206 External circulation crystallization cooler 207 First stage pressure main separator 208 First stage main separator mother liquor / washing liquid tank 209 Cleaning Phenol Pump 210 Slurry mixing and cleaning tank 211 Crystal Slurry Pump 212 Second stage pressure main separator 213 Second stage main separator mother liquor tank 214 Slurry Mixing Washing Mother Liquor Pump 215 Crystal Melting Apparatus 216 Circulation pump for crystal melting equipment 217 Melting Heater 218 Phenol-free supply pump 301 Liquid film falling type dephenolization device 302 Gas-liquid separation tank 303 Steam stripping dephenolation column condenser 304 Steam Stripping Steam Superheater 305 Steam stripping dephenolation tower 306 Phenol absorption tower (306) 307 Phenol Circulation Pump 308 Spray Phenol Cooler 309 Phenol absorption tower condenser 310 Phenol Tank 311 Phenol Dispensing Pump 312 Phenol Cooler 313 Fresh Phenol Tank 314 Fresh Phenol Pump 315 BPA Melt Pump 316 Packaging Machine 401 Mother liquor receiving tank 402 Feed pump for falling film evaporator 403 1st stage supply preheater 404 Second stage supply preheater 405 Low-pressure falling film evaporator 406 Pressurized Falling Film Evaporator 407 First stage gas-liquid separation tank 408 Second stage gas-liquid separation tank 409 Tail Gas Condenser 410 Discharge pump for first stage separation tank 411 Third stage gas-liquid separation tank 412 Crystallizer Feed Pump 413 Crystallizer Feed Cooler 414 Condenser 415 Aftercooler 416 Phenol recovery tank 417 Phenol Dispensing Pump 418 Recovered phenol storage tank 419 Recovery Phenol Pump (419) 420 Recovery Crystallizer 421 External circulation crystallization cooler 422 Crystallization Circulation Pump 423 Pressure Sub-Separator 424 Cleaning liquid receiving tank 425 Cleaning liquid dispensing pump 426 Crystal Melting Apparatus 427 Circulation pump for crystal melting equipment 428 Crystal melting device heater 429 Mother liquor receiver tank 430 Mother liquor discharge pump 431 Mother Liquor Heater 432 Isomerization Reactor 501 Dehydration tower preheater 502 Dehydration tower 503 Dehydration tower reboiler 504 Acetone recovery tower 505 Acetone tower reboiler 506 Acetone column condenser 507 Acetone tower aftercooler 508 Acetone tower reflux tank 509 Acetone tower reflux pump 510 Phase Separator 511 Water phase discharge pump 512 Phenol-containing water cooler 513 Phenol-containing water cooler 514 Phase Separator 515 Ethylbenzene Dispensing Pump 516 Wastewater Pump 517 Ethylbenzene Cooler 518 Dehydration tower tank discharge pump 519 Phenol recovery tower 520 Phenol column reboiler 521 Phenol recovery tower tank discharge pump 522 Phenol column condenser 523 Phenol tower aftercooler 524 Phenol tower reflux tank 525 Reflux pump for phenol recovery tower 526 Ethylbenzene Tank 527 Ethylbenzene supply pump 601 Decomposition supply preheater 602 Falling film evaporator 603 Gas-liquid separation tank 604 p-isopropylphenol removal tower 605 Reboiler 606 Tower kettle discharge pump 607 Condenser 608 Reflux Tank 609 Reflux Pump 610 Decomposition reactor 611 Decomposition reaction circulation pump 612 Decomposition reaction heater 613 Decomposition product condenser 614 Decomposition product tank 615 Transposition Supply Pump 616 Circulating cooler 617 Rearrangement Reactor

Claims

1. A method for producing synthetic bisphenol A by a resin method, comprising: The raw material acetone, recovered acetone, and recycled phenol are sent to the condensation reaction unit (100#) for reaction. The purified fresh acetone is measured and sent to the first-stage reactor (102) and the second-stage reactor (112) in proportion to each other. The acetone sent to the reactor (102) is mixed with the recovered phenol from the decomposition feed preheater (601) and the material from the first-stage circulation pump (105), enters the first-stage cooler (101), and is cooled by circulating water. After that, it enters the first-stage reactors (102-104), and a part of the reaction liquid flowing out of the first-stage reactor (104) is mixed with the recovered acetone from the decomposition feed preheater (601). The first stage phenol is circulated by the first stage circulation pump (105) and returned to the first stage reactor (102), and the remaining part is heated by a dehydration flash heater (106) and then sent to a dehydration flash evaporator (107) to remove some of the water, and the product and unreacted raw materials are simply separated. After that, the reaction liquid is sent to an adduct crystallization unit (200#), and the hydrous phenol is sent to a solvent recovery unit (500#). A part of the raw material phenol is added from the adduct crystallization unit, and the upstream reaction liquid, the recovered phenol from the dephenolization purification unit (300#), and the mother liquor recovery unit (500#) are sent to the adduct crystallization unit (200#). The mother liquor recovery unit (400#) is used to wash the adduct crystal melt from the unit (400#), and after washing, the first-stage centrifuged mother liquor / washing liquid and the second-stage centrifuged mother liquor are sent to the mother liquor recovery unit (400#), the adduct crystal melt is sent to the phenol removal purification unit, the final product BPA is produced in the phenol removal unit, and the hydrous phenol is sent to the solvent recovery unit, and a part of the raw material phenol is added from the mother liquor recovery unit and used to wash the mother liquor, washing liquid, recovered phenol, and recovered BPA from the cracking and rearrangement unit (600#), The mother liquor from the second stage of centrifugation in the mother liquor recovery unit is then sent to the decomposition and rearrangement unit, ethylbenzene is added to the solvent recovery unit as an azeotropic agent, the recovered acetone is sent to the condensation reaction unit, the recovered phenol is sent to the mother liquor recovery unit, and waste water is discharged outside the system. The decomposition and rearrangement unit receives the mother liquor from the second stage of centrifugation in the mother liquor recovery unit and decomposes and rearranges it, the recovered BPA is returned to the mother liquor recovery unit, and isopropyl phenol and waste liquid are discharged outside the system. This is a method for producing synthetic bisphenol A using a resin method, characterized in that

2. Condensation reaction unit (100#): The flash vapor from the dehydration flash evaporator (107) is condensed and cooled by a first flash evaporation condenser (108) and a second flash evaporation condenser (109). The condensate containing water, acetone, and phenol flows into a light fraction receiving tank (124), and the tail gas is sent to a vacuum system. The dehydrated material from the dehydration flash evaporator (107) is mixed with recovered acetone and fresh acetone from the second stream, and then sent to a second-stage cooler (111) by a second-stage feed pump (110). The mixture is cooled with circulating water and then enters the second-stage reactors (112-114). The condensation reaction liquid discharged from the second-stage reactor (114) is mixed with the bottom liquid from a phenol absorption tower (306) and then sent to an adsorption column (115).

2. The process according to claim 1, wherein the reaction mixture enters the light fraction removal column (117), is heated by heat exchange with the bottom liquid of the light fraction removal column (117) in a preheater (116), and then enters the light fraction removal column (117). Water, unreacted acetone, and a part of phenol in the reaction mixture evaporate from the top of the column, and are condensed in a condenser (122) and an aftercooler (123). The tail gas enters a vacuum system, and the condensed liquid flows into the light fraction receiving tank (124), and is sent to the solvent recovery unit (500#) by a discharge pump (125) to recover phenol and acetone. The light fraction removal column reboiler (118) is heated with low-pressure steam, and the bottom product is concentrated and sent by a discharge pump (119). The temperature is lowered by heat exchange in the preheater (116), and then the concentrated product is sent to the condensation reaction liquid receiving tank (120).

3. The adduct crystallization unit (200#): The reaction concentrate from the condensation reaction liquid discharge pump (121) and the adduct crystal melt recovered from the mother liquor recovery unit (400#) of the crystal melting device circulation pump (427) are mixed in the crystallization supply buffer tank (201), then sent out by the crystallization supply pump (202), cooled by the supply cooler (203), and then enters the main circulation type crystallizer (204). The crystal slurry is then pumped into the main circulation type crystallizer (204) by the crystallization circulation pump (205). After being pumped out from the main circulation crystallizer (204), it enters the crystallization cooler (206) and removes the heat of crystallization under the cooling effect of deionized water. The crystal slurry flowing out from the main circulation crystallizer (204) is continuously sent to the pressurized main separator (207) by the flow control valve to carry out solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump (214). The separated mother liquor and washing liquid enter the main separator mother liquor / washing liquid tank (208) and are pumped out by the discharge pump ( The phenol is introduced from the main separator and sent to the mother liquor receiving tank (401) by the phenol pump (311). The phenol is mixed with the filtered adduct crystals in the slurry mixing and washing tank (210) and washed. The crystal slurry after the slurry mixing is sent to the second stage pressurized main separator (212) by the corresponding crystal slurry pump (211), where solid-liquid separation is carried out. The filtrate enters the slurry mixing centrifuge mother liquor tank (213), and the slurry mixing is carried out.

2. The method according to claim 1, wherein the mother liquor is pumped out by a washing mother liquor pump (214) and sent to the pressurized main separator (207) and the pressurized secondary separator (423) respectively for phenol washing, and the filter cake is taken out by a centrifuge and enters a crystal melter (215), and the material in the crystal melter (215) is sent to a heater (217) by a corresponding crystal melt circulation pump (216) for heating, and then returned to the crystal melter (215).

4. The phenol removal purification unit (300#): The adduct melt from the phenol removal feed pump (218) enters the liquid film falling type phenol removal device (301), is evaporated by heating with steam, and enters the gas-liquid separation tank (302). The liquid phase enters the top of the steam stripping phenol removal device (305). The gas phase is condensed by the condenser (303). The tail gas enters the vacuum system, and the condensate enters the phenol tank (310). Fresh phenol from the tank area enters the fresh phenol tank (313) and is pumped out by the fresh phenol pump (314). A portion is metered and sent to the phenol tank (310), and the rest is sent to the recovered phenol tank (416). The phenol in the phenol tank (310) is pumped out by the phenol discharge pump (311) and cooled to a set value by the washed phenol cooler (312) and then sent to the slurry mixing and washing tank (210) to be washed phenol. bisphenol A is obtained as a bisphenol A product; the vapor from the top of the phenol absorber (306) enters the bottom of the phenol absorber (308) and undergoes gas-liquid mass transfer with the absorbed phenol added from the top of the phenol absorber (308); the gas from the top of the phenol absorber (308) enters the phenol absorber condenser (309); the tail gas enters the vacuum system; the condensate, which is hydrous phenol, enters the ethylbenzene tank (526); and the bottom liquid, which is a bisphenol A phenol solution, is sent to a cooler (308) by a phenol circulation pump (307) to be cooled and then returned to the top of the phenol absorber (306).

5. In the mother liquor recovery unit (400#), the material from the mother liquor receiving tank (401) is sequentially sent by the feed pump (402) to the first feed preheater (403) and the second feed preheater (404). The preheater (403) is a thermally coupled heat exchanger, and the heat medium is the gas phase material from the third gas-liquid separation tank (411). The second feed preheater (404) is also a thermally coupled heat exchanger, and the heat medium is phenol from the recovery phenol pump (419). After the two-stage preheating, the material is metered and divided into two parts. One part is sent to the high-pressure falling film evaporator (406). The gas and liquid phases flowing out from the bottom of the high pressure falling film evaporator (406) enter the first stage gas-liquid separation tank (407), the liquid phase is pumped to the third stage gas-liquid separation tank (411) by a pump (410), the gas phase enters the low pressure falling film evaporator (405) as a heat medium, and after condensation, the gas and liquid phases are separated in the second stage gas-liquid separation tank (408), the liquid phase enters the recovery phenol tank (416), the gas phase enters the tail gas condenser (409) and is further condensed by circulating water, and the condensate is sent to the recovery phenol tank (416). The remaining part of the preheated mother liquor is heated and evaporated in the low-pressure liquid film falling evaporator (405), and the gas-liquid two-phase material flowing out from the bottom of the low-pressure liquid film falling evaporator (405) enters the third-stage gas-liquid separation tank (411). A part of the gas phase material enters the first-stage supply preheater (403) as a heat medium, and the remaining part is condensed in the condenser (414) under the action of circulating water. The tail gases of the first-stage supply preheater (403) and the condenser (414) are combined and then enter the aftercooler (415). The condensate is further condensed under the action of circulating water, and the tail gas is sent to a vacuum system. The condensate from the first-stage supply preheater (403), the condenser (414) and the aftercooler (415) flows into the recovered phenol tank (416). The material in the recovered phenol tank (416) is pumped into the recovered phenol storage tank (418) by the phenol discharge pump (417), and then pumped out by the recovered phenol pump (419). After the temperature is lowered by heat exchange in the second-stage supply preheater (404) and the decomposition supply preheater (601),The liquid phase material in the third-stage gas-liquid separation tank (411) is a concentrated bisphenol A phenol solution, which is sent by a crystallization feed pump (412), passed through a crystallization feed cooler (413) and cooled with circulating water, and then enters a recovery crystallizer (420). The adduct crystal slurry is then pumped from the recovery crystallizer (420) by a crystallization circulation pump (422). After being pumped out, the crystallization liquid enters a crystallization cooler (421) where it is cooled with deionized water to remove the heat of crystallization. The crystal slurry flowing out of the recovery crystallizer (420) is continuously sent to a pressure sub-separator (423) for solid-liquid separation. The phenol for washing the filter cake is the filtrate from the second stage centrifuge of the slurry mixed washing mother liquor pump (214). The mother liquor separated from the pressure sub-separator (423) enters a mother liquor receiving tank (429) and is sent out by a mother liquor discharging pump (430). After being preheated by the liquid heater (431), a part of the liquid is sent to the isomerization reactor (432), where 2,4-bisphenol A, triphenol, and part of the chromanol are converted into bisphenol A and then enter the mother liquor receiver (401), and the other part is sent to the cracking and rearrangement unit (600#) for cracking and rearrangement. The wash liquid from the pressure secondary separator (423) enters the wash liquid receiver (424) and is sent to the mother liquor receiver (401) by the wash liquid discharge pump (425), and is then discharged from the main separator. The method according to claim 4, characterized in that a part of the reaction liquid introduced and metered by the condensation reaction liquid discharge pump (121) is mixed with the filtered adduct crystals in a crystal melting device 426, the material in the crystal melting device 426 is sent to a heater (428) by a corresponding crystal melt circulating pump (427) to be heated and then returned to the crystal melting device 426, and the material in the crystal melting device 426 is sent to a crystallization supply buffer tank (201) by the crystal melt circulating pump (427).

6. The solvent recovery unit (500#) is an azeotropic distillation column for dehydration (502), and ethylbenzene is used as an azeotropic agent. The material from the light fraction discharge pump (125) is mixed with the material from the ethylbenzene supply pump (527), and then preheated by low-pressure steam in the dehydration column supply preheater (501). The resulting mixture enters the dehydration column (502). The overhead gas directly enters the acetone recovery column (504). The bottom liquid is phenol containing ethylbenzene, which is sent to the phenol recovery column (519) by the column boiler discharge pump (518). The overhead gas of the acetone recovery column (504) is condensed through the acetone column condenser (506) and the aftercooler (507). The tail gas is sent to the vacuum system. The condensate enters the acetone column reflux tank (508) and is pumped out by the acetone column reflux pump (509).One strand is sent as reflux to the top of the acetone recovery tower, and the other strand is sent as recovered acetone to the suction port of the second-stage feed pump (110) of the reactor of the condensation reaction unit (100#). The bottom product enters a phase separator (510) to form an aqueous phase and an organic phase. The aqueous phase material is sent by an aqueous phase discharge pump (511) and cooled by coolers (512) and (513), and then enters a phase separator (514) to undergo further phase separation. The organic phase flows to the phase separator (510), and the aqueous phase flows to the main reactor. The organic phase of the phase separator (510) is discharged from the boundary region by a wastewater pump (516) as wastewater from the dehydration tower (502) and subjected to biochemical treatment. The organic phase of the phase separator (510) is discharged by an ethylbenzene discharge pump (515), a part of which is returned to the top of the dehydration tower (502) as reflux liquid, and the rest is cooled by an ethylbenzene cooler (517) and then enters the vacuum pump as an auxiliary working liquid for the ethylbenzene liquid ring vacuum pump. The amount of rising steam in the tower is controlled by adjusting the flow rate of the heating steam in the reboiler (505), and the amount of rising steam in the dehydration tower (502) is controlled. The material from the column bottom discharge pump (518) of (502) enters the phenol recovery column (519), the column top gas is condensed through the phenol column condenser (522) and the aftercooler (523), the tail gas enters the vacuum system, the condensate enters the reflux tank (524), a part of it is returned to the column top as reflux by the reflux pump (525), the rest overflows to the ethylbenzene tank (526), ​​the ethylbenzene tank (526) is filled with the water-containing phenol from the phenol absorption column condenser (309).

2. The method according to claim 1, wherein the ethylbenzene tank (526) receives the displaced ethylbenzene and make-up ethylbenzene from the dehydration tower (502) through the ethylbenzene supply pump (527), and the bottom liquid is phenol containing no ethylbenzene, which is sent to the recovered phenol storage tank (416) through the tower bottom discharge pump (521). The amount of rising steam in the tower is controlled by adjusting the flow rate of heating steam in the reboiler (520).

7. In the cracking and rearrangement unit (600#), the mother liquor from the mother liquor discharge pump (430) is preheated by the cracking and feed preheater (601) and then enters the falling film evaporator (602). The cracking and feed preheater (601) is a thermally coupled heat exchanger, and the heat medium is the recovered phenol from the second-stage feed preheater (404). The mother liquor is evaporated in the falling film evaporator (602) by heating with steam, and the gas-liquid two-phase substance enters the gas-liquid separation tank (603). The liquid phase enters the column pot of the cracking reactor (610), and the gas phase enters the p-isopropylphenol removal column (604). The bottom liquid of the p-isopropylphenol removal column (604) is a heavy fraction containing p-isopropylphenol, which is discharged to the outside of the system via a discharge pump (606) and incinerated. The overhead gas is condensed and cooled by a condenser (607). The tail gas enters a vacuum system, and the condensate enters a reflux tank (608) and is then pumped out by a reflux pump (609). A portion of the condensate is returned to the top of the p-isopropylphenol removal column (604) as a reflux for the column, and the other portion enters the top of the decomposition reactor (610) as a reflux for the column. The material overflowing from the reflux tank (608) enters the decomposition product tank (614), and the amount of rising steam in the tower is controlled by adjusting the flow rate of the heated steam in the reboiler (605). The material from the gas-liquid separation tank (603) enters the decomposition reactor (610) and is then sent to the decomposition reactor heater (612) by the decomposition reaction circulation pump (611) to heat the material, and then a certain amount of alkaline solution is added as a catalyst for the decomposition reaction before being returned to the decomposition reactor (610). The tar produced by the decomposition is then returned to the decomposition reactor (610) and is then returned to the decomposition reactor (610) by the decomposition reaction circulation pump (611). The decomposition product is discharged to the outside of the system through a pump (611) and incinerated, the overhead gas of the decomposition reactor (610) is condensed and cooled in a decomposition product condenser (613), the tail gas enters a vacuum system, the condensate enters the decomposition product tank (614), and is then sent by a rearrangement reaction feed pump (615) to a circulation cooler (616) where it is cooled, a part of it is circulated back to the decomposition product tank (614), the other part is used as a feed for the rearrangement reactor (617), and the rearranged material is returned to the mother liquor receiver (401).

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