A slurry washing and impurity removing process, device and application thereof

Abstract

The application discloses a kind of vinylidene chloride polymerization production process in the process of desalination after slurry washing and impurity removal process, device and application thereof.Slurry washing and impurity removal process includes: after desalination, slurry is transferred to washing kettle with overflow port, cold water is sprayed at the top of washing kettle, hot water is introduced at the bottom, and the resin in slurry is swelled and impurities are removed by alternating cold and hot impact washing, under stirring, impurities overflow out of washing kettle with water through overflow port, part of resin flows out of washing kettle bottom with water and is recycled back to the liquid level below slurry washing mixed solution in washing kettle through washing circulating pump.Slurry washing and impurity removal device includes washing kettle with overflow port, cold water spraying device is arranged at the top in washing kettle, hot water inlet pipe and discharge pipe are connected at the bottom in washing kettle, discharge pipe is connected with one end of washing circulating pump, the other end of washing circulating pump is connected with washing kettle through return pipe, and the outlet of return pipe is located below the liquid level of slurry washing mixed solution in washing kettle.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vinylidene chloride (VDC) polymerization production, in particular to a slurry washing and impurity removing process after dialysis in the vinylidene chloride polymerization production process, a device thereof and application thereof. BACKGROUND

[0002] Polyvinylidene chloride (PVDC for short) is a green packaging material, which is unique in the packaging industry, and has the characteristics of high barrier, strong toughness, low temperature heat sealing, good chemical stability and the like. Vinylidene chloride and monomers such as methyl acrylate (MA) are copolymerized to form copolymer multilayer co-extrusion PVDC-MA resin of different grades, which can be used for manufacturing heat shrinkable film, extruded film, composite PVDC film, preservative bag, composite bag, blow molded bottle, fish net silk, flame retardant fabric, artificial turf and the like.

[0003] The example of the description of each process of the existing traditional suspension polymerization method is as follows:

[0004] 1) MA polymerization process:

[0005] High-purity water, antioxidants, additives and dispersants from the dispersant tank are added into the polymerization kettle, nitrogen is replaced, vacuum is extracted by the vacuum unit, vinylidene chloride, methyl acrylate monomers and the like are introduced into the polymerization kettle according to a certain proportion, the initiator weighed is put into the polymerization kettle, the polymerization kettle is heated to a certain temperature by the jacket hot water, the temperature and pressure of the polymerization kettle are controlled, after a period of reaction, when the pressure in the polymerization kettle is reduced to the specified pressure, the program determines that the reaction is completed, and the program automatically adds the termination agent in the termination agent tank into the polymerization kettle to terminate the reaction.

[0006] 2) MA dialysis process:

[0007] The polymerization reaction material obtained after the termination of the polymerization kettle is transported to the dialysis tank by the slurry discharge pump, steam is introduced into the dialysis tank to heat and strip the residual monomers in the slurry, and the epoxy soybean oil (ESO) is added for stirring and uniformity, and the dialyzed slurry is transported to the centrifugal slurry conveying pump for the centrifugal drying process.

[0008] 3) MA tail gas treatment process:

[0009] After the dialyzed mixed monomers are removed by the foam trap, the non-condensable gas is compressed by the tail gas compressor set, and then goes to the primary and secondary condensers, the condensed monomers are recovered to the mixing tank and transported by the mixing pump, and the non-condensable gas at the top of the secondary condenser is discharged to the tail gas spray absorption tower and treated by the circulating absorption of the chilled brine before being vented and discharged.

[0010] 4) centrifugal drying and packaging process:

[0011] The slurry after dialysis is sent into a centrifuge feed tank for stirring for a certain time, and then is delivered to a centrifuge by a centrifugal metering pump. After preliminary centrifugation, it is sent to a fluidized drying bed. After steam heating treatment, it is blown to a vibrating screen, and after two-screen separation, it is sent to a fine material packaging plant for packaging. After the gas phase of the fluidized drying bed is recovered by a cyclone separator I, a cyclone separator II and a bag-type dust collector, the qualified gas is discharged by an induced draft fan.

[0012] The current process has the following shortcomings:

[0013] 1) The powder resin in the slurry after dialysis is prone to wear at the transmission position during centrifugation, causing unstable product quality.

[0014] Due to the influence of the foamed material after the polymerization and dialysis of the PVDC-MA resin, a large amount of powder (dispersants, additives, etc.) is still contained in the pores of the resin particles. When the powder is subjected to high-speed centrifugation in the centrifuge, it may be adsorbed, agglomerated, and accumulated in the form of a block, which is prone to contact with the rotating drum of the centrifuge after a certain period of time, causing wear of the rotating drum. At the same time, the resin may have black and yellow spots.

[0015] 2) High energy consumption:

[0016] Since a large amount of powder is still contained in the slurry after dialysis, the powder is more prone to yellowing as the temperature of the fluidized bed increases during the drying process, which increases the energy consumption required for drying. This process requires a large amount of utilities and electrical consumption, resulting in high production and operation costs.

[0017] 3) Short centrifuge cleaning time and high waste generation:

[0018] Due to the accumulation of block-shaped material, the rotating drum is severely worn, and the centrifuge cleaning time is basically 45 days per time. Each cleaning generates a large amount of wastewater and waste, not only generating three wastes, but also increasing the loss of PVDC products.

[0019] 4) The powder in the slurry after dialysis is prone to clumping during drying, vibration, and mixing due to static electricity, and the presence of a large amount of powder resin has a greater impact on product quality. SUMMARY

[0020] In view of the above technical problems and the deficiencies in the field, the present application provides a slurry washing and impurity removal process, device and application thereof after dialysis in a polyvinylidene chloride polymerization production process.

[0021] The specific technical solution is as follows:

[0022] In a first aspect, the present application provides a slurry washing and impurity removing process after dialysis in a vinylidene chloride polymerization process, comprising: transferring the dialyzed slurry into a washing kettle with an overflow port, spraying cold water at the top of the washing kettle and introducing hot water at the bottom of the washing kettle, and through the cold and hot impact washing alternately to make the resin in the slurry swell and remove the impurities, under stirring, the impurities overflow out of the washing kettle with water through the overflow port, and part of the resin flows out of the bottom of the washing kettle with water and is circulated back to below the liquid level of the slurry washing and mixing liquid in the washing kettle through a washing circulating pump.

[0023] In the present application, the circulating material is circulated back to below the liquid level of the slurry washing and mixing liquid in the washing kettle, so that the resin overflow loss can be avoided.

[0024] In some embodiments, the slurry washing and impurity removing process, the vinylidene chloride polymerization product accounts for 32% to 35%, water accounts for 57% to 60%, and impurities account for 5% to 8% in the dialyzed slurry by mass percentage. Further, the sum of the mass percentages of the vinylidene chloride polymerization product, water and impurities in the dialyzed slurry is 100%.

[0025] In some embodiments, the slurry washing and impurity removing process, the amount of the slurry transferred into the washing kettle is 30 to 40 tons, for example, 35 tons, etc.

[0026] In some preferred embodiments, the slurry washing and impurity removing process, the flow rate of the sprayed cold water is 5 to 10 m 3 / h, for example, 8 m 3 / h, etc.

[0027] In some preferred embodiments, the slurry washing and impurity removing process, the circulating flow rate of the washing circulating pump is 50 to 100 m 3 / h, 70 m 3 / h, etc.

[0028] In some embodiments, the slurry washing and impurity removing process, the cold water is room temperature water, and the temperature of the hot water is higher than 60℃.

[0029] In some preferred embodiments, the slurry washing and impurity removing process, the slurry washing temperature in the washing kettle is controlled at 35 to 60℃.

[0030] In some preferred embodiments, the slurry washing and impurity removing process, the cold impact washing in the cold and hot impact washing refers to that the slurry washing temperature in the washing kettle is controlled at 35 to 45℃, for example, 35 to 40℃, etc., and the hot impact washing refers to that the slurry washing temperature in the washing kettle is controlled at 45 to 60℃, for example, 55 to 60℃, etc. It can be understood that the hot impact washing temperature is higher than the cold impact washing temperature.

[0031] In the present application, the cold-heat shock washing can be achieved by adjusting the amount of cold water spraying and the amount of hot water introduced, for example, the cold shock washing can be achieved by reducing the introduction of hot water or not introducing hot water, maintaining cold water spraying, and reducing the washing temperature; and the hot shock washing can be achieved by increasing the amount of hot water introduced to increase the washing temperature.

[0032] In some preferred examples, the slurry washing and impurity removal process has a washing time of 2-5 hours, for example 3 hours, etc.

[0033] In some preferred examples, the slurry washing and impurity removal process has a total cold shock washing time of 1-4 hours, for example 2 hours, 3 hours, etc., and a total hot shock washing time of 1-4 hours, for example 2 hours, 3 hours, etc.

[0034] In some preferred examples, the slurry washing and impurity removal process has a single cold shock washing time and a single hot shock washing time of 0.5-2 hours, for example 1 hour, 1.5 hours, etc.

[0035] In some preferred examples, the slurry washing and impurity removal process has a ratio of total cold shock washing time to total hot shock washing time of 0.25-4:1, for example 0.5:1, 1:1, 2:1, etc.

[0036] In some preferred examples, the slurry washing and impurity removal process has 2-5 times of alternating cold shock washing and hot shock washing, for example 3 times, 4 times, etc., wherein one alternation is counted when the cold shock washing changes to hot shock washing or when the hot shock washing changes to cold shock washing.

[0037] In some preferred examples, the slurry washing and impurity removal process has a stirring speed of 20-60 rpm, for example 40 rpm, etc.

[0038] In a second aspect, the present application provides a vinylidene chloride polymerization production process, which comprises a polymerization process, a desorption process, and a centrifugation process, and further comprises a washing and impurity removal process between the desorption process and the centrifugation process, wherein the washing and impurity removal process adopts the slurry washing and impurity removal process of the first aspect, the slurry washing and impurity removal process receives the slurry after desorption of the desorption process, and the output of the slurry washing and impurity removal process is sent to the centrifugation process.

[0039] In a third aspect, the present application provides a slurry washing and impurity removing device used in a vinylidene chloride polymerization production process, comprising a washing kettle with an overflow port, a cold water spraying device arranged at the top of the washing kettle, a hot water inlet pipe and a discharge pipe connected to the bottom of the washing kettle, a discharge pipe connected to one end of a washing circulating pump, the other end of the washing circulating pump connected to the washing kettle through a back feeding pipe, the outlet of the back feeding pipe located below the liquid level of the slurry washing and mixing liquid in the washing kettle, and a stirring device arranged in the washing kettle.

[0040] In the present application, the outlet of the back feeding pipe is arranged below the liquid level of the slurry washing and mixing liquid in the washing kettle, so that the circulating material is fed back below the liquid level of the slurry washing and mixing liquid in the washing kettle, thereby avoiding the loss of resin overflow.

[0041] The slurry washing and impurity removing device of the third aspect can be used to perform the slurry washing and impurity removing process of the first aspect.

[0042] The slurry washing and impurity removing process of the first aspect can be performed by using the slurry washing and impurity removing device of the third aspect.

[0043] In a fourth aspect, the present application provides a vinylidene chloride polymerization production device, comprising a polymerization device, a desorption device and a centrifugal device, the vinylidene chloride polymerization production device further comprising the slurry washing and impurity removing device of the third aspect, the washing kettle in the slurry washing and impurity removing device connected to the desorption device, and the other end of the washing circulating pump in the slurry washing and impurity removing device further connected to the centrifugal device.

[0044] The vinylidene chloride polymerization production device of the fourth aspect can be used to perform the vinylidene chloride polymerization production process of the second aspect.

[0045] The vinylidene chloride polymerization production process of the second aspect can be performed by using the vinylidene chloride polymerization production device of the fourth aspect.

[0046] Compared with the prior art, the present application has the following beneficial effects:

[0047] 1) Uniform particle size distribution.

[0048] The purpose of the present application is to provide a process for separating foam material (containing dispersing agent, additive, etc.) from a polymerization product (such as PVDC-MA slurry). Compared with the existing process, the present application adds a washing and impurity removing process, which utilizes a high-speed water flow to form a high-speed rotating flow field in the washing kettle, and the slurry and foam material are separated by swelling under the alternating cold and hot impact washing. Compared with the original process, the final product particle size distribution is increased from 32~120 mesh ≥ 92% to 32~120 mesh ≥ 95%. The more uniform particle size distribution helps the flowability and uniformity of the resin during processing, i.e. has a more optimal melt processing state, thereby the processing stability is more optimal, the film quality is significantly improved, and the processing loss is reduced from 5~8% of the original process to 2~4%.

[0049] 2) High product yield of PVDC.

[0050] The slurry temperature after dialysis is usually 50-70℃. If direct centrifugal drying is performed according to the prior art, powder adsorption and agglomeration are more serious, and blocky material is prone to be produced, and the probability of black and yellow spots in the product is high. Moreover, it is found in the test that if the slurry after dialysis is naturally cooled by more than 10-15℃ and then centrifugal drying is performed, the particle size of the resin product is more dispersed and uneven. The present application uses the newly added washing and impurity removal process, the slurry washing temperature in the washing kettle is controlled at 35-60℃, and the slurry system is cooled by more than 10-15℃ compared with the previous whole body, and then enters the centrifuge and the drying fluidized bed, which significantly reduces the phenomena of powder adsorption and agglomeration, and is not easy to produce blocky material, and greatly reduces the probability of black and yellow spots in the product. Under the condition that the reaction and dialysis system is not changed, the product yield of PVDC is increased from 93% to more than 96%.

[0051] 3) Energy consumption is reduced.

[0052] The suspended polymerization aids and organic dispersants are removed by cold and hot alternating impact swelling washing, the resin is heated more uniformly during drying, and the drying efficiency is significantly improved, so that the goal of reducing heat energy consumption during drying is achieved, the steam consumption is reduced from 1.48t / t to 1.38t / t, and the byproduct resin rate of PVDC product is reduced to less than 4%.

[0053] 4) The cleaning cycle of the centrifugal equipment is prolonged.

[0054] The lower PVDC slurry temperature reduces the blocky material, thereby greatly reducing the subsequent centrifuge drum wear rate and the probability of black and yellow spots in the product, the centrifuge cleaning cycle is reduced from 15 days / time to more than 3 months / time, the production efficiency is effectively improved, and the labor cost is reduced.

[0055] 5) Reduction of three wastes.

[0056] A. The present application can further reduce the original product waste rate and reduce the amount of solid waste generated during the operation process.

[0057] B. The centrifuge cleaning cycle is prolonged by about 1 time during the operation process of the present application, and the annual wastewater amount generated by centrifuge cleaning can be greatly reduced.

[0058] C. The wastewater after washing can be recycled in the operation process of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1 It is a structure diagram of a dialysis slurry washing and impurity removal device in a vinylidene chloride polymerization production process. DETAILED DESCRIPTION

[0060] The application is further described below in conjunction with the accompanying drawings and specific examples. It should be understood that these examples are intended to illustrate the application and are not intended to limit the scope of the application. The methods of operation in the following examples, in which specific conditions are not indicated, are usually performed according to the conventional conditions or according to the conditions recommended by the manufacturers.

[0061] As shown in Figure 1 A slurry washing and impurity removing device for use in the production of vinylidene chloride polymerization, comprising a washing kettle 1 with an overflow port 2 on the side, a cold water spraying device 3 provided on the top inside the washing kettle 1, a hot water inlet pipe 4 and a discharge pipe 5 connected to the bottom inside the washing kettle 1, one end of a washing circulating pump 6 connected to the discharge pipe 5, the other end of the washing circulating pump 6 connected to the washing kettle 1 through a return pipe 7, the outlet of the return pipe 7 lower than the overflow port 2 and below the liquid level of the slurry washing and mixing liquid inside the washing kettle 1, and a stirring device 8 provided inside the washing kettle 1.

[0062] A vinylidene chloride polymerization production device, comprising a polymerization device, a desorption device and a centrifugal device, the vinylidene chloride polymerization production device further comprising the above-mentioned slurry washing and impurity removing device as shown in Figure 1 The washing kettle 1 in the slurry washing and impurity removing device is connected to the desorption device, and the other end of the washing circulating pump 6 in the slurry washing and impurity removing device is further connected to the centrifugal device.

[0063] A slurry washing and impurity removing process for use in the production of vinylidene chloride polymerization after desorption, using the above-mentioned slurry washing and impurity removing device as shown in Figure 1 The process comprises: transferring the desorbed slurry into the washing kettle 1 with an overflow port 2 on the side, spraying cold water on the top of the washing kettle 1 through the cold water spraying device 3, introducing hot water through the hot water inlet pipe 4 at the bottom, washing the slurry by alternating cold and hot impact to swell the resin and remove impurities, under the stirring of the stirring device 8, the impurities overflow out of the washing kettle 1 through the overflow port 2 along with the water, part of the resin flows out of the washing kettle 1 through the discharge pipe 5 at the bottom and is circulated back to below the liquid level of the slurry washing and mixing liquid inside the washing kettle 1 through the washing circulating pump 6 and the return pipe 7.

[0064] The slurry washing and impurity removing process after the above-mentioned polymerization of vinylidene chloride is a method for separating methyl acrylate (MA), vinylidene chloride (VDC), dispersant and other impurities from a mixture of polyvinylidene chloride (PVDC) high-performance barrier material containing methyl acrylate (MA), vinylidene chloride (VDC) and dispersant, and obtaining high-purity polyvinylidene chloride (PVDC). The method is a washing and impurity removing process newly added between the original MA dialysis process and the centrifugal drying process. The resin slurry after dialysis is pumped into the washing kettle 1 by the centrifugal slurry delivery pump, and then high-pressure high-purity water is used at a certain temperature, the spraying flow and stirring speed are controlled, and the high-speed circulation washing is performed for a certain time combined with the washing circulating pump 6. The upper washing water overflows to the washing liquid collection tank for collection, and then is pumped to other processes by the washing liquid delivery pump for recycling of the related waste water. The qualified slurry after washing is sent to the next centrifugal drying process by the washing circulating pump 6.

[0065] In this embodiment, the mixture of 50-70℃ (PVDC slurry weight percentage composition: PVDC 35%, water 60%, and impurity foam 5%) is added to the washing kettle 1 at a feeding rate of 5 t / h, and the one-pot batch mixture mass is 35 tons. The high-purity water is used for alternating cold and hot impact washing in the range of 35-60℃, the spraying flow of the cold water spraying device 3 is controlled at 8 m 3 / h, the stirring speed of the stirring device 8 is controlled at 40 rpm, and the 70 m 3 / h circulation washing is performed for 3 h combined with the washing circulating pump 6. The upper washing water overflows to the washing liquid collection tank for collection, and then is pumped to other processes by the washing liquid delivery pump for recycling of the related waste water. The PVDC high-efficiency slurry is obtained at the bottom of the washing kettle 1, and is sent to the next centrifugal drying process by the washing circulating pump 6. In this embodiment, the cold water sprayed by the cold water spraying device 3 is room temperature water, and the temperature of the hot water introduced by the hot water inlet pipe 4 is higher than 60℃. In this embodiment, the alternating cold and hot impact washing is sequentially performed for the first cold impact washing 1 h-hot impact washing 1 h-second cold impact washing 1 h, for a total of 3 h. The cold impact washing refers to that the slurry washing temperature in the washing kettle 1 is controlled at 35-40℃, and the hot impact washing refers to that the slurry washing temperature in the washing kettle is controlled at 55-60℃.

[0066] A vinylidene chloride polymerization production process includes a polymerization process, a dialysis process and a centrifugal process. The vinylidene chloride polymerization production process further includes a washing and impurity removing process located between the dialysis process and the centrifugal process. The washing and impurity removing process adopts the above-mentioned slurry washing and impurity removing process. The slurry washing and impurity removing process receives the slurry after dialysis of the dialysis process. The output of the slurry washing and impurity removing process is sent to the centrifugal process.

[0067] By such cleaning, the particle size distribution of the final product obtained by centrifugal drying can be improved from 92% of 32-120 mesh to 95% of 32-120 mesh. By using the impurity removal method of the present application, the slurry system is cooled to 35-40°C and then enters the centrifuge and the drying fluidized bed, which significantly reduces the adsorption and agglomeration of powders, and the yield of PVDC products is increased from 93% to more than 96% (including). The cleaning cycle of the subsequent centrifuge is reduced from 15 days / once to more than 3 months / once, effectively improving the production efficiency and reducing the labor cost.

[0068] Furthermore, it is to be understood that, based on the above description of the present application, those skilled in the art can make various modifications or changes to the present application, and these equivalent forms also fall within the scope defined by the claims attached hereto.

Claims

1. A production process of vinylidene chloride polymerization comprising a polymerization step, a desorption step and a centrifugation step, characterized in that, The vinylidene chloride polymerization production process further comprises a washing and impurity removing process between the desalting process and the centrifugal process, the washing and impurity removing process adopts a washing and impurity removing process for the slurry after desalting in the vinylidene chloride polymerization production process, the washing and impurity removing process receives the slurry after desalting in the desalting process, and the output of the washing and impurity removing process is sent to the centrifugal process. The washing and impurity removing process for the slurry after desalting in the vinylidene chloride polymerization production process comprises the following steps: transferring the PVDC-MA slurry after desalting into a washing kettle with an overflow port, spraying cold water on the top of the washing kettle, introducing hot water into the bottom of the washing kettle, swelling the resin in the slurry to remove impurities through the cold and hot impact washing alternately, and under stirring, the impurities overflow out of the washing kettle with the water through the overflow port, and part of the resin flows out of the bottom of the washing kettle with the water and is circulated back to below the liquid level of the slurry washing mixed solution in the washing kettle through the washing circulating pump. The slurry washing temperature in the washing kettle is controlled at 35-60℃. The cold impact washing in the cold and hot impact washing refers to that the slurry washing temperature in the washing kettle is controlled at 35-40℃, and the hot impact washing refers to that the slurry washing temperature in the washing kettle is controlled at 55-60℃. The time for single cold impact washing and single hot impact washing in the cold and hot impact washing is 1-2 hours.

2. The production process of poly(vinylidene chloride) according to claim 1, characterized in that, The vinylidene chloride polymer product accounts for 32%-35% of the slurry after desalting, the water accounts for 57%-60%, and the impurities account for 5%-8% by mass percentage.

3. The production process of poly(vinylidene chloride) according to claim 2, characterized in that, The sum of the mass percentages of the vinylidene chloride polymer product, the water and the impurities in the slurry after desalting is 100%.

4. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The amount of the slurry transferred into the washing kettle is 30-40 tons.

5. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The flow rate of the sprayed cold water is 5 to 10 m 3 / h.

6. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The circulation flow rate of the washing cycle pump is 50 to 100 m 3 / h.

7. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The cold water is room temperature water, and the temperature of the hot water is higher than 60℃.

8. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The time for the slurry to be washed in the washing kettle is 2-5 hours.

9. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The total time for the cold impact washing in the cold and hot impact washing is 1-4 hours, and the total time for the hot impact washing is 1-4 hours.

10. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The ratio of the total time for the cold impact washing to the total time for the hot impact washing in the cold and hot impact washing is 0.25-4:

1.

11. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The number of times for the cold impact washing and the hot impact washing to alternate with each other in the cold and hot impact washing is 2-5 times.

12. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The stirring speed is 20-60 rpm.

13. The process for the polymeric production of epichlorohydrin according to claim 1, characterized in that, The washing and impurity removing process for the slurry after desalting in the vinylidene chloride polymerization production process adopts a washing and impurity removing device for the slurry after desalting in the vinylidene chloride polymerization production process. The washing and impurity removing device for the slurry after desalting in the vinylidene chloride polymerization production process comprises a washing kettle with an overflow port, a cold water spraying device arranged on the top of the washing kettle, a hot water inlet pipe and an outlet pipe connected to the bottom of the washing kettle, one end of the outlet pipe connected to a washing circulating pump, the other end of the washing circulating pump connected to the washing kettle through a back feeding pipe, the outlet of the back feeding pipe located below the liquid level of the slurry washing mixed solution in the washing kettle, and a stirring device arranged in the washing kettle.

14. The production process of poly(vinylidene chloride) according to claim 13, characterized in that, The vinylidene chloride polymerization production process adopts a vinylidene chloride polymerization production device, the vinylidene chloride polymerization production device comprises a polymerization device, a desalting device, a centrifugal device and the washing and impurity removing device, the washing kettle in the washing and impurity removing device is connected to the desalting device, and the other end of the washing circulating pump in the washing and impurity removing device is further connected to the centrifugal device.

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