CN202626071U - Device for increasing conversion ratio of acrylonitrile in styrene-acrylonitrile copolymerization reaction - Google Patents

Abstract

The utility model relates to a petrochemical device and particularly relates to a device for increasing the conversion ratio of acrylonitrile in styrene-acrylonitrile copolymerization reaction. After the copolymerization reaction of two reactors in series, two forced reflux pipelines are respectively added to the two reactors, partial materials are forcibly refluxed to the reactors, the mixing of reactants in the reactors is strengthened, the materials in the reactors are enabled to be evenly mixed, the conversion ratio of the acrylonitrile is over 75% and reaches 80%, the productivity is increased, the single productivity of the device is increased to 80,000 ton/year, the production operation is stable, the degree of mixing of the materials in the reactors is even, and the product quality is of a leading international level. According to the device for increasing the conversion ratio of the acrylonitrile in the styrene-acrylonitrile copolymerization reaction, after reaction, the remaining amount of monomers and solvents is reduced, the monomer yield is increased, the cost for the recovery of the monomers and solvents is saved, the equipment investment cost for a production unit is saved, and the running cost of the device is saved, thus the production cost of products is lowered.

Description

A kind of device that improves vinyl cyanide transformation efficiency in the styrene-acrylonitrile copolyreaction

Technical field

The utility model relates to a kind of device of petrochemical complex, particularly a kind of device of acrylonitrile-styrene copolymerized reaction.

Background technology

Acrylonitritrile-styrene resin is also claimed SAN or AS, is a kind of by vinyl cyanide and the styrene copolymerized macromolecular compound that forms.Acrylonitritrile-styrene resin has thermoplasticity; Not easy to change; Do not receive the influence of diluted acid, diluted alkaline, rare pure and mild gasoline; Have good thermotolerance and solvent resistance, be used to make oil resistant mechanical component, meter housing, panel board, cell box, tractor fuel tank, battery cell case, packaging vessel, daily necessities etc., still a kind of main as the blend composition of producing ABS resin.

In the suitability for industrialized production implementation process, first-generation emulsion polymerization has been experienced in synthesizing of styrene-acrylonitrile copolymer in industrializing implementation, and the s-generation is hanged newborn polymerization, third generation continuous bulk polymerization method.Said emulsion polymerization is owing to complex manufacturing, and the cost height has been on the verge of to eliminate.The product poor transparency that said outstanding newborn polymerization is produced can only be used for the ABS resin of base-material blending.It is pure that the styrene-acrylonitrile copolymer that said continuous bulk polymerization method makes has a product, and transparency height, oil resistant, the good characteristics of chemical resistance are compound methods of styrene-acrylonitrile copolymer the most frequently used in the industry.The continuous bulk polymerization method adopts thermal initiation continuous bulk polymerization technology, is monomer with vinylbenzene, vinyl cyanide, adds a spot of ethylbenzene and comes synthesizing styrene-acrylonitrile copolymer as diluting solvent.

Mass polymerization is produced in the styrene-acrylonitrile copolymer technology, and the subject matter of existence is that the vinyl cyanide transformation efficiency is low.Because the styrene-acrylonitrile copolymer viscosity that reaction generates is very big, after for some time took place in reaction, reactant mixed inhomogeneous, the contact difficulty between the reactant, even if the augmenting response residence time, the vinyl cyanide transformation efficiency also can only reach 50%～70%wt.If, material in reactor is mixed through strengthening stir speed (S.S.), then can cause breakdown of emulsion, influence quality product.So existing mass polymerization is produced in the technology of styrene-acrylonitrile copolymer, generally adopts the less tandem reactor of two volumes.Nonetheless, second reactor exit, the vinyl cyanide transformation efficiency also only can reach 70%wt.

The vinyl cyanide transformation efficiency is low, can cause following adverse consequences: at first, this can cause raw material availability low, poor product quality; Secondly, this can reduce the single line throughput of styrene-acrylonitrile copolymer, and the ton product-specific investments increases; In addition, this also can increase in follow-up unreacted monomer and the solvent recovery unit, the amount of unreacted monomer and solvent, the facility investment and the process cost of increase unreacted monomer and solvent recovery unit.This is a urgent problem during styrene-acrylonitrile copolymer is produced.

Summary of the invention

The purpose of the utility model provides a kind of device that improves vinyl cyanide transformation efficiency in the acrylonitrile-styrene copolymerized reaction and improve product single line throughput.

The technical scheme of the utility model, according to the acrylonitrile-styrene copolymerized reaction later stage, material in reactor viscosity is very big, the characteristics of the contact difficulty between the reactant; Behind two placed in-line reactor drums, add a forced refluence pipeline respectively, with the partial material forced refluence in reactor drum; Strengthen the mixing of reactant in the reactor drum; Can not cause under the condition of breakdown of emulsion, make the interior mixing of materials of reactor drum even, to improve the transformation efficiency of vinyl cyanide.

A kind of device that improves vinyl cyanide transformation efficiency in the styrene-acrylonitrile copolyreaction comprises that reaction mass has vinyl cyanide, vinylbenzene, thinner, molecular weight regulator, is characterized in that; Vinyl cyanide and reaction mass get into the 1# reactor drum through 1# reactor feed mouth, and product and unreacted reactant are through 1# reactor drum discharging pump; A part is sent into the 2# reactor drum, and another part turns back to the 1# reactor drum through 1# reactor content refluxing opening; On 1# reactor drum return wire, be provided with 1# reactor pressure valve, on the 2# reactor feed line, be provided with 1# reactor drum level control valve; Be provided with 1# reactor drum condensing surface in the 1# reactor head, the gaseous component that volatilizes in the 1# reactor drum is back to after its condensation in the 1# reactor drum; Withdraw from reaction heat, when the transformation efficiency of 1# reactor bottom vinyl cyanide reaches 60%, send into the 2# reactor drum; Material gets into the 2# reactor drum through 2# reactor feed mouth, and reaction product and unreacted reactant are through the 2# of 2# reactor bottom reactor drum discharging pump; A part is sent into the subsequent products centrifugal station, and another part is by reflux pipeline, from 2# reactor feed refluxing opening; Return the 2# reactor drum, on the return wire of 2# reactor drum, be provided with a 2# reactor pressure valve, going to be provided with 2# reactor drum level control valve on the pipeline of centrifugal station; In the 2# reactor head; Be provided with a 2# reactor drum condensing surface, the gaseous component that volatilizes in the 2# reactor drum is back to after its condensation in the 2# reactor drum; When the vinyl cyanide transformation efficiency of 2# reactor bottom reaches 80%, the material in the 2# reactor drum is sent into centrifugal station.

The advantage of the utility model is; Strengthen mixing through the reactant forced-flow, improve the degree of uniformity of mixing of materials in the reactor drum, and increase the residence time of material in reactor drum; The transformation efficiency of reactor outlet vinyl cyanide by 50%～70%wt, is brought up to 75～80%wt.The backflow of liquid makes the mixing of material in reactor more even, therefore can adopt the bigger reactor drum of volume, under the prerequisite of the transformation efficiency that does not reduce vinyl cyanide, with the single line throughput raising of acrylonitrile-styrene polymkeric substance.Because transformation efficiency has improved 10%～30%wt, reaction back unreacted monomer and solvent residual content are few.Like this, can reduce the yield of unreacted monomer and solvent, save the investment cost and the working cost of this part unit equipment, thus the energy consumption of saving and reduce product cost.

Description of drawings

Fig. 1 is the device general flow chart of the utility model.

Wherein: 1# reactor drum 1,1# reactor drum discharging pump 2,1# reactor drum condensing surface 3,1# reactor pressure valve 4,1# reactor drum level control valve 5; 1# reactor agitator 6,1# reactor feed mouth 7,1# reactor drum discharge port 8,1# reactor agitator motor 9,1# reactor content refluxing opening 10; 2# reactor drum 11,2# reactor drum discharging pump 12,2# reactor drum condensing surface 13,2# reactor pressure valve 14; 2# reactor drum level control valve 15,2# reactor agitator 16,2# reactor feed mouth 17,2# reactor drum discharge port 18; 2# reactor agitator motor 19,2# reactor content refluxing opening 20,1# reactor jacket 21,2# reactor jacket 22.

Embodiment

Below in conjunction with accompanying drawing 1 and specific embodiment, the utility model is made detailed description.

A kind of device that improves vinyl cyanide transformation efficiency in the styrene-acrylonitrile copolyreaction; The material of reaction has vinyl cyanide, vinylbenzene, thinner, molecular weight regulator, and thinner is an ethylbenzene, and molecular weight regulator is a lauryl mercaptan; The material ratio of copolyreaction; Vinyl cyanide: vinylbenzene: ethylbenzene: lauryl mercaptan=(20%～30%): (50%～70%): (10%～35%): (0～2%) by weight percentage, is expressed as %wt; Vinyl cyanide, vinylbenzene get into 1# reactor drum 1 respectively through 1# reactor feed mouth 7, and deep fat is heated to 110 ℃ in reactor jacket 21, get into thermal initiation.Because reaction is the heat radiation reaction; The temperature of carrying out with reaction can constantly raise; For preventing implode, begin to react the back and adopt recirculated water to remove heat, to guarantee that temperature of reaction is between 140～160 ℃; Keep reacting kettle inner pressure between 0.16～03MPaG through conditioned reaction still top condensing surface quantity of reflux, reaction time is 1.8～2.0 hours.Product and unreacted reactant are through 1# reactor drum discharging pump 2, and a part is sent into 2# reactor drum 11, and another part turns back to 1# reactor drum 1 through 1# reactor content refluxing opening 10, and reflux ratio is 0.28～0.35.On 1# reactor drum 1 return wire, a 1# reactor pressure valve 4 is installed, a 1# reactor drum level control valve 5 is installed on 2# reactor drum 11 feeding lines.When the pressure of 1# reactor drum discharging pump 2, in the time of not in setting range, regulate the aperture of 1# reactor pressure valve 4 on the return wire, make pump discharge pressure return to setting range.At this moment, in the 1# reactor drum 1, liquid level can change accordingly, regulates the aperture of 1# reactor drum level control valve 5 on 2# reactor drum 11 feeding lines, makes 1# reactor drum 1 liquid level return to setting range.Be provided with a 1# reactor drum condensing surface 3 at 1# reactor drum 1 top, the gaseous component that volatilizes in the 1# reactor drum 1 is back to after its condensation in the 1# reactor drum 1, withdraws from reaction heat.Through the height and the reaction time of liquid level in the control 1# reactor drum 1, control the transformation efficiency of vinyl cyanide in the 1# reactor drum 1.When the transformation efficiency of 1# reactor drum 1 bottom vinyl cyanide reaches 60%, send into 2# reactor drum 11.

Material gets into 2# reactor drum 11 through 2# reactor feed mouth 17, in reactor jacket 22, feeds deep fat and is heated to 110 ℃, gets into thermal initiation.Because reaction is the heat radiation reaction; The temperature of carrying out with reaction can constantly raise; In order to prevent implode, begin to react the back and adopt recirculated water to remove heat, to guarantee that temperature of reaction is between 140～160 ℃; Keep reacting kettle inner pressure between 0.16～0.3MPaG through conditioned reaction still top condensing surface quantity of reflux, reaction time is 1.8～2.0 hours.Reaction product and unreacted reactant, through the 2# reactor drum discharging pump 12 of 2# reactor drum 11 bottoms, a part is sent into the subsequent products centrifugal station; Another part is by reflux pipeline; From 2# reactor content refluxing opening 20, return 2# reactor drum 11, reflux ratio is 0.28～0.4.At 2# reactor drum 11, a 2# reactor pressure valve 14 is installed on the return wire, going that a 2# reactor drum level control valve 15 is installed on the pipeline of centrifugal station.When the pressure of 2# reactor drum discharging pump 12, in the time of not in setting range, regulate the aperture of 2# reactor pressure valve 14 on the return wire, make pump discharge pressure return to setting range.At this moment, in the 2# reactor drum 11, liquid level can change accordingly, regulates the aperture of 2# reactor drum level control valve 15, makes 2# reactor drum 11 liquid levels return to setting range.At 2# reactor drum 11 tops, be provided with a 2# reactor drum condensing surface 13, the gaseous component that volatilizes in the 2# reactor drum 11 is back to after its condensation in the 2# reactor drum 11.Through the height and the reaction time of liquid level in the control 2# reactor drum 11, control the transformation efficiency of vinyl cyanide in the 2# reactor drum 11.When the vinyl cyanide transformation efficiency of 2# reactor drum 11 bottoms reaches 80%, the material in the 2# reactor drum 11 is sent into centrifugal station.

Following specific embodiment, as shown in table 1:

Certain device of the utility model behind two placed in-line reactor drums, adds a forced refluence pipeline respectively, with the partial material forced refluence in reactor drum; Strengthen the mixing of reactant in the reactor drum, make the interior mixing of materials of reactor drum even, the transformation efficiency of vinyl cyanide is more than 75%; Reach 80%, its throughput improves, and the single line throughput of device is brought up to 80,000 tons/year; Production operation is stable, and the mixing of materials degree is even in the reactor drum, and quality product is in the leading level in the world.Monomer and solvent residual content reduce after the reaction of the utility model; The monomer yield is improved, and the cost of monomer and solvent recuperation obtains saving, and the facility investment expense of productive unit obtains saving; The working cost of device obtains saving, thereby has reduced production cost of products.

Table 1

Claims (1)

1. a device that improves vinyl cyanide transformation efficiency in the styrene-acrylonitrile copolyreaction comprises that reaction mass has vinyl cyanide, vinylbenzene, thinner, molecular weight regulator, is characterized in that; The material of vinyl cyanide and reaction gets into 1# reactor drum (1) through 1# reactor feed mouth (7), and the reactant of product and end reaction is through 1# reactor drum discharging pump (2); A part is sent into 2# reactor drum (11), and another part turns back to 1# reactor drum (1) through 1# reactor content refluxing opening (10); On 1# reactor drum (1) return wire, be provided with 1# reactor pressure valve (4), on 2# reactor drum (11) feeding line, be provided with 1# reactor drum level control valve (5); Be provided with 1# reactor drum condensing surface (3) at 1# reactor drum (1) top; The gaseous component that volatilizes in the 1# reactor drum (1) is back to after its condensation in the 1# reactor drum (1), withdraws from reaction heat; When the transformation efficiency of 1# reactor drum (1) bottom vinyl cyanide reaches 60%, send into 2# reactor drum (11); Material gets into 2# reactor drum (11) through 2# reactor feed mouth (17), reaction product and unreacted reactant, the 2# reactor drum discharging pump (12) through 2# reactor drum (11) bottom; A part is sent into the subsequent products centrifugal station, and another part is by reflux pipeline, from 2# reactor feed refluxing opening (20); Return 2# reactor drum (11), on the return wire of 2# reactor drum (11), be provided with a 2# reactor pressure valve (14), going to be provided with 2# reactor drum level control valve (15) on the pipeline of centrifugal station; At 2# reactor drum (11) top; Be provided with a 2# reactor drum condensing surface (13), the gaseous component that volatilizes in the 2# reactor drum (11) is back to after its condensation in the 2# reactor drum (11); When the vinyl cyanide transformation efficiency of 2# reactor drum (11) bottom reaches 80%, the material in the 2# reactor drum (11) is sent into centrifugal station.