CN2474534Y

CN2474534Y - Polymer solution devolatization device

Info

Publication number: CN2474534Y
Application number: CN 01238667
Authority: CN
Inventors: 夏燕敏; 石正金; 王平; 华良
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology; China Petrochemical Corp
Priority date: 2001-04-04
Filing date: 2001-04-04
Publication date: 2002-01-30
Anticipated expiration: 2011-04-04

Abstract

The utility model relates to a devolatization apparatus for the polymer solution, which mainly solves the problems in the prior literature that the devolatization amount is small, the devolatization effect is bad or the overfeeding of the material is easy to happen, all the problems are solved by the technical project of employing the double screw vacuum devolatization apparatus, an exhaust port of the devolatization apparatus is provided with two to seven screw blocks, wherein the length of the exhaust section is that the diameter of the bolt is 2-8, the depth of the groove of the exhaust section is that the diameter of the bolt is 0.15-0.5, the utility model can be used in the device of the polymer devolatization industry.

Description

Polymers soln devolatilization device

The utility model relates to a kind of polymers soln devolatilization device.

Mass polymerization is the common method of producing polymkeric substance.All be provided with the devolatilization device in the modern mass polymerization flow process, polymer performance had dysgenic unreacted monomer, inert additwe, solvent borne impurity and oligopolymer, reduce volatilization component residual quantity in the polymkeric substance, reach the purpose that improves polymer quality to remove.In these devolatilization methods and the device, mainly comprised heat exchanger and devolatilizer in the past.For example CN1163897A, CN2209156Y have all narrated method and/or the device that removes residual volatilization component in the polymeric system, its devolatilization method is: at first this reaction mass is preheated to 150 ℃～300 ℃ through over-heat-exchanger, make material have certain temperature and viscosity, enter the volatilization component that removes the overwhelming majority in the devolatilizer with certain vacuum degree then, thereby the component residual quantity that obtains volatilizing is lower than the following copolymer product of 1000PPm.The problem that this method and/or apparatus structure exist is: in the devolatilization condensation process of volatilization component, after devolatilization component process single-stage or the multipole refrigerating apparatus condensation, still be difficult to avoid producing the backflow that has removed a small amount of volatilization component monomer.Because the devolatilization mouth of devolatilization pipeline is located immediately at the upstream of material feeding region, the direct access to plant material feeding region of a small amount of phegma and the devolatilization system that make volatilization component condensation generation.Aforesaid method can influence the quality product after the devolatilization on the one hand; This phegma also can cause the overflow of devolatilization mouth on the other hand, causes the devolatilization line clogging, makes this device can not reach gratifying devolatilization effect.

Set forth a kind of equipment and method of from rare glue, producing solid polymer in the document US 3963558.This method is to be the rare glue heating flash evaporation in thickener earlier of 5～50% (weight) with solid content, obtains the glue of 30～80% (weight) solid content, enters in the degassing extruder then.This forcing machine had also been installed the column type current limiting element before two front-seat gas ports except rear exhaust port is arranged, and have gas to propose agent to add inlet, and the back pressure control valve is equipped with in the screw rod exit, though therefore energy consumption is lower, whole plant is quite complicated.

Set forth a kind of equipment and process that from solution, reclaims polymkeric substance in the document US 4686279.Elder generation is with polymkeric substance pre-concentration to 80～99% (weight) before entering twin screw, control the polymer fluid flow that enters twin screw by valve regulated pressure reduction then, and the rotating speed of regulating twin screw makes polymkeric substance be in half full state in screw channel, thereby devolatilization can be carried out effectively.Owing to used pre-devolatilizer, therefore, the devolatilization ability of twin screw seems very limited.

Proposed to contain the process for devolatilization of styrene-maleic anhydride copolymer among the document CN1187503A, but from the result, the devolatilization amount only is 1～3 kilogram of/hour resin.

A kind of polymkeric substance devolatilization device has been proposed among the document CN2368848Y, this apparatus features is that a container that can receive the phegma of volatilization component condensation generation is arranged between devolatilizer and vacuum unit, for improving the polymeric articles quality, prevent that devolatilization line clogging etc. from having certain effect, but can not fundamentally eliminate the overflow that other application cause.

The purpose of this utility model is to exist the devolatilization amount little in the above document in order to overcome, and devolatilization weak effect or easily cause the shortcoming of overflow provides a kind of new polymers soln devolatilization device.It is big that this devolatilization device has the devolatilization processing power, and devolatilization is effective and be difficult for causing the characteristics of overflow.

The purpose of this utility model is to realize by following technical scheme: a kind of polymers soln devolatilization device, mainly form by twin screw vacuum devolatilizer and vacuum unit, vacuum unit links to each other with the venting port of twin screw vacuum devolatilizer, the venting port of twin screw vacuum devolatilizer adopts 2～7 threaded blocks, exhaust section length wherein: screw diameter is 2～8, the exhaust section spiral groove depth: screw diameter is 0.15～0.5.

In the technique scheme, the venting port preferred version of twin screw vacuum devolatilizer adopts 3～5 threaded blocks, exhaust section length: the screw diameter preferable range is 2～6, the exhaust section spiral groove depth: the screw diameter preferable range is 0.15～0.35, and the vacuum unit preferred version is a vacuum pump.

In the utility model, owing to adopt the combination of 2～7 threaded blocks, kept not only that twin screw mixes preferably, transport capacity, also made the devolatilization ability strengthen greatly.Venting port adopts the threaded block of widely-pitched and dark screw channel, make and keep suitable pressure distribution and devolatilization ratio in the twin screw between venting port, make material be difficult for causing overflow on the one hand, avoid solid accumulation, thereby the devolatilization amount is increased, simultaneously after devolatilization, obtained the polymkeric substance that volatilization component residual quantity in the material is lower than 900PPm, obtained effect preferably.

Fig. 1 is an exhaust twin screw extruder synoptic diagram.

Fig. 2 is an exhaust section threaded block structural representation.

Among Fig. 1,1 is the polymer fluid storage tank, and 2 is high-viscosity pump, and 3 is drive-motor, 4 is reduction box, and 5 is opening for feed, and 6 is first venting port, and 7 is second venting port, 8 is the 3rd venting port, and wherein three venting ports all link to each other with the vacuum unit vacuum pump, and 9 is machine barrel, and 10 is die head.

Among Fig. 2,11 is twin screw, and 12 is extruder barrel, and 13 is that venting port is simplified, and 14 is venting port, and D is the true footpath of screw rod, and h is the exhaust section spiral groove depth, and Lv is an exhaust section length.

Below by embodiment the utility model is further elaborated.[embodiment 1]

Be that 45% polymers soln adds in the twin screw of screw-rod structure of the present utility model and venting port with the speed of high sticking toothed gear pump with 38.5 kilograms/hour with solid content, Lv/D=6, h/D=0.25, the temperature of three venting ports is respectively 170 ℃, 225 ℃, 240 ℃, vacuum tightness is respectively 0.040,0.070,0.096MPa, the residual list of vinylbenzene is 879PPm in the resin after the devolatilization, and resin yield is 17.3 kilograms/hour.[comparative example 1]

Adopt the twin screw of original mixed milling type helicitic texture and common venting port, with solid content is that 45% polymers soln adds in the twin screw with the speed of high sticking toothed gear pump with 20 kilograms/hour, the temperature of three venting ports is respectively 170 ℃, 225 ℃, 240 ℃, vacuum tightness is respectively 0.040,0.070,0.096MPa, the residual list of vinylbenzene is 1298PPm in the resin after the devolatilization, resin yield is 9 kilograms/hour, if improve treatment capacity, then the overflow phenomenon can take place.[embodiment 2～5]

All adopt the utility model vented extruder to carry out the devolatilization test, concrete data see Table 1.[comparative example 2]

Adopt common degassing extruder to carry out the devolatilization test, concrete data see Table 1.

Table 1

Sequence number	Reinforced concentration %	The feeding quantity kilogram/hour	Screw speed rev/min	T ₁ ℃	T ₂ ℃	T ₃ ℃	P ₁ MPa	P ₂ MPa	P ₃ MPa	Lv/D	h/D	The residual single PPm of resin
Sequence number	Reinforced concentration %	The feeding quantity kilogram/hour	Screw speed rev/min	T ₁ ℃	T ₂ ℃	T ₃ ℃	P ₁ MPa	P ₂ MPa	P ₃ MPa	Lv/D	h/D	The residual single PPm of resin	Embodiment 1	45	38.5	52	170	225	240	0.040	0.070	0.096	6	0.25	879
Comparative example 1	45	20	52	170	225	240	0.040	0.070	0.096			1298	Embodiment 1	45	38.5	52	170	225	240	0.040	0.070	0.096	6	0.25	879
Comparative example 1	45	20	52	170	225	240	0.040	0.070	0.096			1298	Embodiment 2	51	45	68	140	190	260	0.040	0.070	0.097	2	0.25	717
Comparative example 2	51	22	68	140	190	260	0.040	0.070	0.097			1356	Embodiment 2	51	45	68	140	190	260	0.040	0.070	0.097	2	0.25	717
Comparative example 2	51	22	68	140	190	260	0.040	0.070	0.097			1356	Embodiment 3	60	55	52	140	230	260	0.023	0.070	0.097	4	0.25	491
Embodiment 4	60	60	52	140	230	260	0.023	0.070	0.097	5	0.15	557	Embodiment 3	60	55	52	140	230	260	0.023	0.070	0.097	4	0.25	491
Embodiment 4	60	60	52	140	230	260	0.023	0.070	0.097	5	0.15	557	Embodiment 5	57	65	55	140	230	240	0.025	0.060	0.097	6	0.35	830

Claims

1, a kind of polymers soln devolatilization device, mainly form by twin screw vacuum devolatilizer and vacuum unit, vacuum unit links to each other with the venting port of twin screw vacuum devolatilizer, the venting port that it is characterized in that twin screw vacuum devolatilizer adopts 2～7 threaded blocks, exhaust section length wherein: screw diameter is 2～8, the exhaust section spiral groove depth: screw diameter is 0.15～0.5.

2,, it is characterized in that the venting port of twin screw vacuum devolatilizer adopts 3～5 threaded blocks according to the described polymers soln devolatilization of claim 1 device.

3, according to the described polymers soln devolatilization of claim 1 device, it is characterized in that exhaust section length: screw diameter is 2～6.

4, according to the described polymers soln devolatilization of claim 1 device, it is characterized in that the exhaust section spiral groove depth: screw diameter is 0.15～0.35.

5,, it is characterized in that vacuum unit is a vacuum pump according to the described polymers soln devolatilization of claim 1 device.