CN102898571A - Apparatus for enhancing product quality of acrylonitrile-styrol copolymer - Google Patents

Abstract

The invention relates to a petrochemical industry apparatus, and provides an apparatus for enhancing the product quality of an acrylonitrile-styrol copolymer, which is characterized in that a 1# flash evaporation device for removing acrylonitrile is provided and a 2# flash evaporation device used for removing toluene, styrene and residual acrylonitrile with minute quantity is provided. According to the invention, toluene is used as a diluent which has important meaning. The invention has the following beneficial effects that the thermal load of two flash evaporation device preheaters is smaller than that of the current devices, compared with the current apparatus, the dissipating energy is saved by 43500kJ/ton SAN resin product, the acrylonitrile is removed under the temperature of 110 DEG C, polymerization generation proportion of an acrylonitrile monomer which is not reacted is reduced, the yellow index of the product can be decreased to less than 5%; under same temperature, the viscosity of the toluene is smaller than the viscosity of the ethylbenzene, the toluene taken as a diluent is in favor of volatilization of acrylonitrile and styrene, the residual monomer amount of the product can be reduced to 700-800ppm, the reduction accounts for 50% of the volume of the apparatus, the production energy consumption is reduced, and the product quality is increased.

Description

A kind of device that improves the acrylonitritrile-styrene resin quality product

Technical field

The present invention relates to a kind of device of petrochemical complex, particularly a kind of device that improves the acrylonitritrile-styrene resin quality product.

Background technology

Acrylonitritrile-styrene resin also claims SAN resin or AS resin, is by vinyl cyanide and the styrene copolymerized high molecular polymer that forms, and has good processing characteristics.The SAN resin has good dimensional stability, weathering resistance, thermotolerance, oil-proofness, anti-vibration resistance and chemical stability, have widely application in fields such as automobile, building, stationery, five metals household electrical appliances and modern functions materials, and be the main blend composition of production ABS resin.Therefore, the SAN resin has become engineering plastics indispensable in our daily life.

Synthesizing of styrene-acrylonitrile copolymer, the emulsion polymerization of the first-generation, the outstanding newborn polymerization of the s-generation in industrializing implementation, have been experienced, third generation continuous bulk polymerization method till now.The styrene-acrylonitrile copolymer that the continuous bulk polymerization method makes, the pure property that has product than the product of other two kinds of methods is good, transparency is high, has the good characteristics such as oil resistant, chemical resistance, is the synthetic method of styrene-acrylonitrile copolymer the most frequently used in the present industry.But, owing to still have many problems in the styrene-acrylonitrile copolymer production, affect its quality product and cost.For example, styrene-acrylonitrile copolymer production energy consumption height causes cost higher; The ratio of product separation stage vinyl cyanide self-polymerization causes its yellowness index of product high; The residual monomer content height causes large, the bad mechanical property of product odour, unstable product quality.These all are urgent problems during styrene-acrylonitrile copolymer is produced.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art, a kind of device that reduces the acrylonitritrile-styrene resin production energy consumption and improve the quality of products is provided.

The production of acrylonitritrile-styrene resin, adopt the reactor of two series connection, usually use ethylbenzene to make the thinner of polymerization reactant and product separation operation, and the present invention uses toluene to be thinner, after acrylonitrile-styrene copolymerized reactant generates, separating of its resultant of reaction and unreacted reactant, the improvement of technological process is to reducing the acrylonitritrile-styrene resin production energy consumption and improving the quality of products significant.

Existing apparatus uses ethylbenzene to make the thinner of polyreaction and product separation workshop section, and this device uses toluene to be thinner.

The boiling point of toluene is 110.8 ℃, and the boiling point of ethylbenzene is 136.2 ℃.

Service temperature at product separation stage one-level flasher is 105～110 ℃, and the service temperature of existing apparatus is 110～120 ℃.

It is significant as thinner that the present invention uses toluene.

A kind of device that improves acrylonitritrile-styrene resin production quality product is characterized in that, is provided with the 1# flasher, removes vinyl cyanide, is provided with the 2# flasher, removes toluene, vinylbenzene and remaining minute quantity vinyl cyanide.

After reactor generation copolyreaction, reaction product and unreacted monomer enter 1# flasher preheater, the laggard 1# flasher of preheating, flash distillation is by 1# flasher discharging pump, material enters the additive mixing tank, reenters 2# flasher preheater, 1# flasher flash gas, after the 1# condenser condenses, enter the 1# surge tank, reenter the 3# surge tank.The 1# surge tank is connected with 1# flasher phlegma and reclaims pump, gives its phlegma to the copolyreaction operation.

Material enters the flash distillation of 2# flasher after entering the preheating of 2# flasher preheater, and flash distillation is by 2# flasher discharging pump, product removes underwater pelletizer, after the flash distillation of 2# flasher, gas enters the 2# condenser, reenters the 2# surge tank, 2# surge tank bottom has 1# to reclaim pump, toluene, vinylbenzene and remaining minute quantity vinyl cyanide are reclaimed, enter Roots vaccum pump through the 2# surge tank, gas reenters the 3# condenser, material advances the 3# surge tank, reclaims blowback by 2# and receives vinyl cyanide; Not solidifying gas enters water ring vacuum pump and 4# surge tank through the 3# surge tank, its afterbody gas emptying.

1# flasher preheater processing parameter uses hot oil medium material to be preheating to 105～110 ℃, rate of flow of fluid 0.1～0.2m/s; 1# flasher processing parameter, 105～110 ℃, absolute pressure 30～45kPa A; 1# condenser condenses processing parameter, outlet material temperature are 5 ℃; 2# flasher preheater processing parameter uses hot oil medium material to be preheating to 220～240 ℃, rate of flow of fluid 0.05～0.15m/s; 2# flasher processing parameter, 220～240 ℃, absolute pressure 2.5～3.5kPa A;

2# condenser processing parameter, outlet material temperature are 5 ℃; 3# condenser processing parameter, outlet material temperature are 40 ℃;

XX kPaA in this specification sheets, the expression absolute pressure, XX%wt represents mass percent.

Beneficial effect of the present invention is, the thermal load of two flasher preheaters is all little than existing apparatus, not only make the energy consuming ratio existing apparatus save 43500kJ/ ton SAN rosin products, and under 110 ℃ of low temperature, removed vinyl cyanide, the ratio of unreacted acrylonitrile monemer generation self-polymerization reaction is reduced, and the yellowness index of product can be down to below 5%.Under uniform temp, the viscosity ratio ethylbenzene viscosity of toluene is little a lot, makees thinner with it and more is conducive to vinyl cyanide and cinnamic volatilization, the residual monomer amount of product can be down to 700～800ppm, only be 50% of existing apparatus, production energy consumption reduces, and quality product improves.

Description of drawings

Fig. 1 is device general flow chart of the present invention.

1# flasher preheater 1 is arranged, 1# flasher 2,1# flasher discharging pump 3,1# condenser 4 among the figure, 1# surge tank 5, additive mixing tank 6,3# surge tank 7, water ring vacuum pump 8,2# flasher 9,2# flasher preheater 10,2# condenser 11,2# surge tank 12,2# flasher discharging pump 13,1# reclaims pump 14, Roots vaccum pump 15,3# condenser 16,2# reclaims pump 17,4# surge tank 18, and 1# flasher phlegma reclaims pump 19.

Embodiment

Below in conjunction with the drawings and specific embodiments the present invention is described in detail.

Specific embodiment has shown in the table 1.

Vinyl cyanide and vinylbenzene are take toluene as thinner, in reactor, react, reaction product and unreacted monomer enter 1# flasher preheater 1 with the flow velocity of 0.1～0.2m/s, after being preheating to 110 ℃, deep fat enters 1# flasher 2,1# flasher 2 is provided with heating jacket, heating medium uses deep fat, flash distillation under 105～110 ℃, 30～45kPa A.

Gaseous phase materials by 1# flasher 2 tops volatilize enters 1# surge tank 5 after 1# condenser 4 is condensed to 5 ℃, leftover materials are sent into additive mixing tank 6 through the 1# flasher discharging pump 3 of 1# flasher 2 bottoms.In order to guarantee to enter the flash distillation effect of 1# flasher 2, the material pressure before the working pressure variable valve control throttling expansion.Working pressure control in the 1# flasher 2 is controlled by the material line adjusted valve that 1# surge tank 5 flows into 3# surge tank 7.The water ring vacuum pump 8 of gaseous phase materials in the 1# surge tank 5 after by 3# surge tank 7 sucks.Liquid phase material in the 1# surge tank 5 reclaims pump 19 through 1# flasher phlegma and sends into the copolyreaction operation.Regulate the rotating speed of 1# flasher discharging pump 3 according to the fluid level controller of 1# flasher 2 bottoms, and then control the inventory of sending into additive mixing tank 6.

1# flasher 2 removes vinyl cyanide, in order to prevent removing simultaneously part toluene, the viscosity of material is increased, hinder polymer masses and be input to 2# flasher 9, enter the 2# flasher 9 front a certain amount of toluene of adding that need at material, reduce the viscosity of polymer masses, carry with convenient.In additive mixing tank 6, add toluene, flow velocity with 0.05～0.15m/s after fully mixing enters 2# flasher preheater 10, after being preheating to 240 ℃, deep fat enters 2# flasher 9,2# flasher 9 is provided with heating jacket, heating medium uses deep fat, enter 2# flasher 9 after the preheating, flash distillation under 220～240 ℃, 2.5～3.5kPa A.Gaseous phase materials by 2# flasher 9 tops volatilize enters 2# surge tank 12 after 2# condenser 11 is condensed to 5 ℃, residue SAN product is delivered to underwater pelletizer through the 2# flasher discharging pump 13 of 2# flasher 9 bottoms.Enter 2# flasher 9 materials, adopt the front material pressure of pressure regulator valve control throttling expansion, to guarantee the flash distillation effect of 2# flasher 9.Regulate the rotating speed of 2# flasher discharging pump 13 according to the liquid level of 2# flasher 9 bottoms, guarantee to send into the amount of the SAN product of underwater pelletizer.Working pressure in the 2# flasher 9 enters the variable valve on the material line of 2# surge tank 12 by control, control.Liquid phase material in the 2# surge tank 12 reclaims pump 14 by 1# and delivers to the copolyreaction operation, regulates the flow that 1# reclaims pump 14 according to the liquid level in the 2# surge tank 12.Gaseous phase materials in the 2# surge tank 12 is drawn into 3# condenser 16 by the Roots vaccum pump 15 behind the 2# surge tank 12, be condensed to 40 ℃ after, send into 3# surge tank 7.Liquid phase material in the 3# surge tank reclaims pump 17 by 2# and delivers to the copolyreaction operation, according to the liquid level in the 3# surge tank 7, regulates the flow that 2# reclaims pump 17.Gaseous phase materials in the 3# surge tank 7 sucks 4# surge tank 18 by the water ring vacuum pump 8 behind the 3# surge tank 7.The liquid phase component of 4# surge tank 18 bottoms is back to water ring vacuum pump 8, the gas phase emptying at top.

Table 1

The service temperature of 1# flasher 2 is lower, and vinyl cyanide self-polymeric reaction can not occur substantially, and the yellowness index of product can reduce.The service temperature of two flashers, with traditional be that the device service temperature of thinner is low with ethylbenzene, the duty ratio existing apparatus of its preheater is little, the product of 1 ton of SAN resin of every production needs heat to can save energy 43500kJ.Toluene viscosity ratio ethylbenzene viscosity under the uniform temp is little a lot, makees thinner with it and more is conducive to vinyl cyanide and cinnamic volatilization, so the residual monomer amount of product can be down to 700～800ppm.The yellowness index of the product of SAN resin can be down to below 5%, and quality product improves.

Claims (1)

1. a device that improves acrylonitritrile-styrene resin production quality product is characterized in that, is provided with 1# flasher (2), removes vinyl cyanide, is provided with 2# flasher (9), removes toluene, vinylbenzene and remaining minute quantity vinyl cyanide;

After reactor generation copolyreaction, reaction product and unreacted monomer enter 1# flasher preheater (1), the laggard 1# flasher of preheating (2), flash distillation is by 1# flasher discharging pump (3), material enters additive mixing tank (6), reenters 2# flasher preheater (10), 1# flasher (2) flash gas, after 1# condenser (4) condensation, enter 1# surge tank (5), reenter 3# surge tank (7); 1# surge tank (5) is connected with 1# flasher phlegma and reclaims pump (19), gives its phlegma to the copolyreaction operation;

After material enters 2# flasher preheater (10) preheating, enter 2# flasher (9) flash distillation, flash distillation is by 2# flasher discharging pump (13), product removes underwater pelletizer, after 2# flasher (9) flash distillation, gas enters 2# condenser (11), reenter 2# surge tank (12), 2# surge tank (12) bottom has 1# to reclaim pump (14), with toluene, vinylbenzene and remaining minute quantity vinyl cyanide reclaim, and enter Roots vaccum pump (15) through 2# surge tank (12), and gas reenters 3# condenser (16), material advances 3# surge tank (7), reclaims pump (17) recover acrylonitrile by 2#; Not solidifying gas enters water ring vacuum pump (8) and 4# surge tank (18) through 3# surge tank (7), its afterbody gas emptying;

1# flasher preheater (1) processing parameter uses hot oil medium material to be preheating to 105～110 ℃, rate of flow of fluid 0.1～0.2m/s; 1# flasher (2) processing parameter, 105～110 ℃, absolute pressure 30～45kPaA; 1# condenser (4) condensation process parameter, the outlet material temperature is 5 ℃; 2# flasher preheater (10) processing parameter uses hot oil medium material to be preheating to 220～240 ℃, rate of flow of fluid 0.05～0.15m/s; 2# flasher (9) processing parameter, 220～240 ℃, absolute pressure 2.5～3.5kPa A;

2# condenser (11) processing parameter, the outlet material temperature is 5 ℃; 3# condenser (16) processing parameter, the outlet material temperature is 40 ℃;

XX kPaA in this specification sheets, the expression absolute pressure, XX%wt represents mass percent.

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