Vinylene carbonate production process and device

Abstract

The invention relates to a vinylene carbonate production process and device, reaction raw materials are subjected to a dechlorination reaction in a reaction kettle, a reaction liquid enters a sedimentation type continuous filtering and washing device through a delivery pump, by-products are subjected to sedimentation, filtration and solvent washing and are separated from the reaction liquid, and the vinylene carbonate is obtained. Reaction liquid and washing liquid are combined through an overflow port in the upper portion of the device, the shaft wall of the stirring shaft, the bottom-inserted discharging pipe and a filtrate outlet of the filtering jacket respectively, and are conveyed to a reaction liquid intermediate receiving tank through a circulating pump to be continuously synthesized. Or conveying back to the reaction kettle for intermittent synthesis; the completely reacted reaction liquid and the tertiary amine hydrochloride washing liquid overflow or are filtered out from the sedimentation type continuous filtering and washing device, enter an intermediate receiving tank, are purified by a desolventizing tower, a low component removal tower, a high component removal tower and a rectifying tower, and then are subjected to melt crystallization to obtain a vinylene carbonate product with the purity of 99.99% or above; settled and washed slurry residues are discharged from the bottom of the device and then neutralized and separated with liquid caustic soda, and an organic phase is dehydrated, recycled and recycled.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium ion battery additives, and in particular relates to a production process and device for vinylene carbonate. Background Art

[0002] Vinylene carbonate, with its high dielectric constant and low viscosity, is currently the most commonly used electrolyte additive. It can significantly improve the electrochemical performance of electrolytes, increasing coulombic efficiency and charge capacity retention. With the rapid development of new energy vehicles and energy storage in recent years, the importance of vinylene carbonate has become increasingly prominent.

[0003] Currently, the main principles of the industrial production methods of vinylene carbonate are similar. They all use vinylene carbonate as a raw material, react with chlorine under ultraviolet light to synthesize vinyl chloride carbonate; then, in an organic solvent, the vinyl chloride carbonate reacts with a tertiary amine to remove hydrogen chloride to produce crude vinylene carbonate; the obtained crude vinylene carbonate is then purified by distillation and crystallization to finally produce vinylene carbonate with higher purity.

[0004] Research has found that the reaction of tertiary amines with chloroethylene carbonate is a typical dehydrohalogenation reaction, but during the reaction process, the tertiary amine will cause the generated vinylene carbonate to further generate polymers, resulting in the loss of vinylene carbonate and a reduction in yield. In the prior art, the synthesis process of vinylene carbonate is mainly a kettle-type dropwise addition reaction, which is an intermittent operation. That is, a quantitative tertiary amine is added dropwise to a substrate previously composed of chloroethylene carbonate, a solvent, and a polymerization inhibitor, and the reaction is filtered after a period of time. The filtrate is subjected to precipitation and purification to obtain vinylene carbonate. Since the dechlorination reaction is a highly exothermic reaction, a violent and highly exothermic reaction will occur after the tertiary amine is added dropwise and accumulated to a certain amount, resulting in a "flyaway" phenomenon, which is prone to solvent boiling out of control and poses a great safety hazard. Therefore, it is difficult to increase the volume of the reactor. In addition, during the intermittent reaction process, the tertiary amine added dropwise in the early stage cannot be consumed in time, resulting in a large excess of tertiary amine in the reaction system relative to the product vinylene carbonate, which leads to instability of the vinylene carbonate, an increased probability of side reactions, and an increase in polymers, thereby resulting in a decrease in yield. The polymers produced by side reactions are viscous, tarry, or pitch-like, which further contaminate the reaction system, making filtration and post-processing of the reaction liquid difficult. This results in a reaction yield of only around 60%, low production efficiency, a high concentration of waste products, and high energy consumption. Particularly in the later stages of the crude distillation process, a large amount of asphalt-like polymer, with high viscosity, forms at the bottom of the crude distillation equipment. This not only affects the purity of the vinylene carbonate but also severely impairs the heat transfer efficiency of the distillation equipment's inner walls, making them difficult to clean. This ultimately reduces the overall heat transfer efficiency of the distillation process.

[0005] In addition, the existing industrial production process of vinylene carbonate accumulates a large amount of heat and has low production efficiency. At the same time, due to the long reaction time and the large amount of polymer generated, the yield of vinylene carbonate is low, which makes it difficult to meet the requirements of large-scale industrial production. Summary of the Invention

[0006] One of the problems to be solved by the present invention is that the traditional synthesis process of vinylene carbonate is mainly a kettle-type dropwise reaction, intermittent operation, low production efficiency, a lot of three wastes, high energy consumption and other problems;

[0007] The second problem to be solved by the present invention is that as the reaction proceeds, the generated polymer accumulates and wraps around the tertiary amine hydrochloride generated by the reaction, and adheres to the wall of the reactor. After the reaction is completed, the reactor is difficult to clean, and the cleaning solution will also cause an increase in the three wastes.

[0008] The third problem to be solved by the present invention is that the polymerization of vinylene carbonate itself and the reaction with excess tertiary amine result in a reduced yield of vinylene carbonate and a purity that does not meet the requirements.

[0009] The object of the present invention is to overcome the defects in the prior art and provide a production process and device for vinylene carbonate, which can improve production efficiency, reduce the generation of three wastes, reduce energy consumption and costs, reduce material polymerization, and improve the yield of vinylene carbonate products.

[0010] In order to solve one of the above problems, the technical solution adopted by the present invention is: to improve the existing synthesis process design, eliminate the accumulation of reaction heat, reduce the number of equipment and the number of workers, thereby improving production efficiency, reducing the amount of three wastes generated, reducing energy consumption and costs, and improving the inherent safety of the process.

[0011] In order to solve the second problem mentioned above, the technical solution adopted by the present invention is: in the production process, the solvent and tertiary amine hydrochloride are separated in time. The relative density of tertiary amine hydrochloride is greater than that of the liquid, and it will be precipitated and separated from the reaction system, thereby reducing the occurrence of side reactions and improving the product yield.

[0012] In order to solve the third problem mentioned above, the technical solution adopted by the present invention is to use a sedimentation-type continuous filtration and washing device to filter and wash the settled tertiary amine hydrochloride slurry, bring the vinylene carbonate product entrained in the tertiary amine hydrochloride slurry into the reaction liquid, and wash off the polymer entrained by the tertiary amine hydrochloride, thereby avoiding the accumulation of polymers on the surface of the tertiary amine hydrochloride and causing viscosity, thereby improving the yield of vinylene carbonate; at the same time, adding a high-efficiency polymerization inhibitor to the reaction system can prevent the polymerization of vinylene carbonate itself and the reaction with the tertiary amine, thereby further improving the yield.

[0013] A production process for vinylene carbonate comprises the following steps:

[0014] S1: The solvent is continuously fed into the reactor through the preheater by controlling the flow rate through the solvent delivery pump and flow meter; when the solvent feed amount reaches a certain mass, warm water or steam is introduced into the reactor jacket to preheat and keep the solvent warm;

[0015] When the solvent in the reactor reaches a certain temperature, the flow rate is controlled by a delivery pump and a flow meter respectively, and the solvent, chloroethylene carbonate and tertiary amine are continuously passed through a preheater and a pipeline mixer at a certain flow rate, and are input into the reactor from the feed port at the top of the reactor for dechlorination reaction. The reaction heat is removed by cooling water introduced into the jacket of the reactor and evaporation of the solvent in the reactor. The solvent in the reactor absorbs the reaction heat and evaporates, and is evaporated from the gas phase port at the top of the reactor. After being cooled by a two-stage heat exchanger of circulating water and chilled water, it is received in a solvent receiving tank and recycled.

[0016] S2: The slurry in the reactor is continuously fed into the sedimentation type continuous filtration and washing device from the discharge valve at the bottom of the reactor through a slurry delivery pump. The by-product tertiary amine hydrochloride generated by the reaction naturally settles in the sedimentation section of the sedimentation type continuous filtration and washing device, and the reaction liquid is filtered through the metal sintered filter screen of the stirring shaft wall and the spiral ribbon of the sedimentation type continuous filtration and washing device, and then discharged from the bottom discharge pipe in the stirring shaft, filtered through the metal sintered filter screen on the wall of the sedimentation section, and then discharged from the filtrate discharge port of the jacket, and the clear liquid on the upper part of the sedimentation section cylinder is discharged from the overflow port; the settled tertiary amine hydrochloride is discharged downward through the spiral ribbon of the stirring shaft into the washing section of the sedimentation type continuous filtration and washing device, and the solvent is controlled by the washing solvent delivery pump and the flow meter, and is continuously fed from the washing solvent inlet of the washing section to wash the reaction by-product tertiary amine hydrochloride, and the washing liquid is filtered through the metal sintered filter screen of the stirring shaft wall and the spiral ribbon of the stirring shaft. The tertiary amine hydrochloride is discharged from the bottom discharge pipe in the mixing shaft, filtered through the metal sintered filter screen on the wall of the washing section, and then discharged from the filtrate discharge port of the jacket; the tertiary amine hydrochloride continues to settle in the washing section and is discharged downwardly through the spiral ribbon of the mixing shaft into the filter drying section of the sedimentation-type continuous filtration and washing device. The washing liquid continues to be filtered through the shaft wall and the metal sintered filter screen on the spiral ribbon, and then discharged through the bottom discharge pipe in the mixing shaft, filtered through the metal sintered filter screen on the wall of the filter drying section, and then discharged from the filtrate discharge port of the jacket; finally, the filtered tertiary amine hydrochloride is pushed by the spiral ribbon of the filter drying section and discharged from the bottom discharge valve, and the mixed slurry of tertiary amine hydrochloride and residual solvent is continuously discharged into the neutralization kettle; the overflow and filtered reaction liquid and washing liquid from the settling section, washing section, and filter drying section are combined and fed into the reaction liquid intermediate receiving tank through a circulation pump to achieve continuous synthesis, or returned to the reactor from the filtrate feed port at the top or middle of the reactor for circulation to achieve intermittent synthesis;

[0017] S3: The reaction liquid and washing liquid after the continuous synthesis or batch synthesis reaction are overflowed and filtered out from the sedimentation continuous filtration and washing device, and are input into the intermediate receiving tank through the circulation pump, and then continuously distilled. The solvent is first separated and recovered through the desolventizing tower, the low-boiling tower, and the high-boiling tower, and then returned to S1 or S2 for synthesis or washing, and high-boiling substances are removed to obtain crude vinylene carbonate;

[0018] S4: The crude vinylene carbonate is purified by distillation in a primary distillation tower and a secondary distillation tower to obtain refined vinylene carbonate;

[0019] S5: The vinylene carbonate product passes through the primary melt crystallizer and the secondary melt crystallizer to obtain a finished vinylene carbonate product with a purity of more than 99.99%, which enters the vinylene carbonate finished product receiving tank;

[0020] S6: The tertiary amine hydrochloride slurry discharged from S2 enters the neutralization kettle, is neutralized by adding liquid alkali, and then transferred to the separator tank for stratification. The upper organic phase enters the dehydration tower of the recovery system for dehydration, and then enters the solvent recovery tower for distillation to recover the solvent, and the tertiary amine recovery tower for distillation to recover the tertiary amine. The recovered solvent can be returned to S1 or S2 for reuse, and the recovered tertiary amine can be reused in S1;

[0021] S7: The brine separated from the lower layer of the S6 separator tank passes through a single-effect or multi-effect evaporation system, and the evaporated wastewater enters the sewage treatment system for biochemical treatment; the salt slurry discharged by evaporation is transferred to the rotary kiln of the waste liquid incinerator for high-temperature calcination to remove organic matter, and the obtained sodium chloride is sold as a by-product or treated as general solid waste.

[0022] As a further technical solution, the tertiary amine is selected from N,N-dimethylethylamine, N,N-dimethyl-n-propylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylhexylamine, N,N-dimethylcyclohexylamine, N,N-dimethylaniline, diethylmethylamine, di-n-propylmethylamine, diisopropylmethylamine, triethylamine, triisopropylamine, tributylamine, pyridine, N-methylpyrrole, N-methylpyrrolidine, N-methylmorpholine, One or more combinations of N-methylpiperidine, imidazole, N-methylimidazole, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylbutanediamine, N,N,N',N'-tetramethylhexanediamine, N,N'-dimethylpiperazine, pentamethyldiethylenetriamine, triethylenediamine, 1,5-diazabis[4.3.0]non-5-ene, and 1,8-diazabicyclo[5.4.0]undec-7-ene.

[0023] As a further technical solution, the solvent is a hydrocarbon, ether, ester, or nitrile compound, more typically selected from one or more mixtures of n-hexane, cyclohexane, n-heptane, petroleum ether, dichloromethane, dichloroethane, methyl propyl ether, ethyl propyl ether, methyl tert-butyl ether, n-propyl ether, isopropyl ether, ethyl formate, n-propyl formate, isopropyl formate, n-butyl formate, isobutyl formate, tert-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, methyl propionate, ethyl propionate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and acetonitrile; the density of the solvent or mixed solvent at 25° C. is less than 1.0; the solvent contains The polymerization inhibitor contains 0.01 to 0.5% of a polymerization inhibitor, which is a combination of one or more of phenols, quinones, phenothiazines, phosphites, piperidinols, and piperidine nitrogen oxides. Typical polymerization inhibitors are hydroquinone, p-methoxyphenol, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,5-di-tert-butylhydroquinone, phenothiazine, 2,2,6,6-tetramethyl-4-hydroxy-piperidine nitrogen oxide, tris(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) phosphite, and bis(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) sebacate.

[0024] As a further technical solution, the mass ratio of the solvent, ethylene chloride carbonate, and tertiary amine is 2.0-10.0:1.0:0.8-1.5; the reaction temperature is controlled at 50-100° C.; and the residence time of the ethylene chloride carbonate and tertiary amine in the reactor C for the dechlorination reaction is 1-16 hours to carry out the dechlorination reaction.

[0025] As a further technical solution, temperature measuring devices are installed on the pipelines connecting the rear end of the preheater for the solvent, ethylene chloride, and tertiary amine and the front end of the pipeline mixer. Temperature measuring devices are also installed at the top, middle, and bottom of the reactor. These temperature measuring devices are interlocked with flow meters in the DCS control room and controlled. If the measured temperature of the materials in the reactor exceeds the reaction temperature range, heat exchange is performed through the reactor jacket, while the feed flow rate or the preheating temperature of the raw materials is reduced.

[0026] A vinylene carbonate production device comprises: a solvent delivery pump, a chloroethylene carbonate delivery pump, a tertiary amine delivery pump, a solvent preheater, a chloroethylene carbonate preheater, a tertiary amine preheater, a pipeline mixer, a reactor, a circulating water condenser, a chilled water condenser, a solvent receiving tank, an intermediate receiving tank, a desolventizing tower, a low-pressure degassing tower, a high-pressure degassing tower, a primary distillation tower, a secondary distillation tower, a primary melt crystallizer, a secondary melt crystallizer, and a vinylene carbonate finished product receiving tank, which are connected in sequence. The device also comprises a sedimentation-type continuous filtering and washing device, which is connected to a discharge valve at the bottom of the reactor. The sedimentation-type continuous filtering and washing device comprises three cylindrical parts: a sedimentation section, a washing section, and a filtration and drying section, which are connected in sequence. The slurry discharge valve at the bottom of the filtration and drying section is connected in sequence to a neutralization kettle, a liquid separator, a dehydration tower, a solvent recovery tower, and a tertiary amine recovery tower.

[0027] As a further technical solution, a feed port is provided at the top center of the reactor, and the feed pipe is extended into the interior of the reactor and connected to a liquid distributor, the plane of the liquid distributor is parallel to the cross-section of the reactor; the feed port is connected to the pipeline mixer; a gas phase port is provided on the upper part of the reactor, which is connected to the circulating water condenser and the chilled water condenser; filtrate feed ports are also provided on the upper and middle parts of the outer cylinder wall of the reactor, which are connected to the circulating pump; a discharge valve is provided at the bottom of the reactor, and the discharge valve is an automatic switch valve, which is connected to the slurry inlet of the sedimentation-type continuous filtration and washing device; the plane diameter of the liquid distributor is 100 to 2000 mm; the diameter of the reactor cylinder is 500 to 4000 mm, and the height of the cylinder is 1000 to 10000 mm; a jacket is provided on the outside of the reactor, and a heat exchange medium is passed through, and the heat exchange medium includes but is not limited to steam, thermal oil, chilled water, and circulating water.

[0028] As a further technical solution, the sedimentation section, washing section and filter section of the sedimentation type continuous filtering and washing device are provided with a stirring shaft inside the cylinder. The upper part of the stirring shaft is driven by a motor through a reducer. The stirring shaft is a hollow shaft, and a spiral ribbon is installed on the stirring shaft. The spiral ribbon is a hollow structure; a bottom discharge pipe is provided inside the stirring shaft, and the top of the bottom discharge pipe is connected to the filtrate pipeline; the shaft wall and spiral ribbon of the stirring shaft can be fully or partially a three-layer composite plate with a metal sintered filter mesh sandwiched between two layers of perforated plates, and the hollow inner cavity of the stirring shaft is connected to the bottom discharge pipe. The inner cavity of the spiral ribbon is connected; the filtrate is filtered into the inner cavity through the shaft wall of the stirring shaft and the composite plate of the spiral ribbon, and is discharged through the top outlet of the bottom discharge pipe in the stirring shaft; the bottom end of the stirring shaft is a solid shaft, and is fixed and supported by a sleeve or a bearing; if necessary, the middle part of the stirring shaft, that is, the connection between the three parts of the cylinder of the sedimentation section, the washing section, and the drying section, can be fixed with several bearings or sleeves; the speed of the stirring shaft can be adjusted by a reducer and a frequency converter according to the solid content of the slurry; the spiral ribbon can be a segmented or broken line continuous spiral ribbon.

[0029] As a further technical solution, a slurry inlet is provided in the middle of the cylinder of the sedimentation section, which is connected to the discharge valve at the bottom of the reactor, an overflow port for the settled and clarified reaction liquid is provided on the upper part of the cylinder of the sedimentation section, and a filtrate discharge outlet is provided on the lower part of the outer wall of the jacket; the washing section can be composed of one or more sections of cylinders, each section of the cylinder is provided with a washing solvent inlet on the upper part, and a filtrate discharge outlet is provided on the lower part of the outer wall of the jacket; the filtrate discharge outlet is provided on the lower part of the outer wall of the jacket of the drying section cylinder; the cylinder wall of the sedimentation section, washing section and drying section can be a single-layer structure or a double-layer jacket structure; the inner wall of the double-layer jacket structure is a three-layer composite plate with a metal sintered filter mesh sandwiched between two layers of perforated plates, and the outer wall of the jacket is a solid steel plate; the lower part of the cylinder of the drying section is equipped with a sleeve or bearing for supporting the stirring shaft, and the bottom outlet is equipped with a slag slurry discharge valve with automatic opening and closing or adjustment function.

[0030] As a further technical solution, the material of the three parts of the cylinder, namely the sedimentation section, the washing section and the filtration section, is one of carbon steel, glass lining, stainless steel, steel lined with plastic, steel sprayed with plastic, titanium, and alloy steel; the material of the stirring shaft and the spiral ribbon is one of carbon steel, stainless steel, titanium, and alloy steel metal materials.

[0031] As a further technical solution, the cylinder walls, stirring shafts and spiral ribbons of the three parts of the cylinder, namely the sedimentation section, the washing section and the drying section, are not all solid structures at the same time.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The production process has been improved, with the conversion rate of vinyl chloride carbonate ≥98% and the total yield of vinylene carbonate relative to vinyl chloride carbonate ≥70%, which greatly improves the production efficiency and target product yield, reduces the generation of three wastes, and reduces energy consumption and labor costs.

[0034] 2. The boiling point of the solvent is lower than that of the tertiary amine, the relative density is less than 1.0, and the solubility of the tertiary amine hydrochloride is low, which is conducive to separation.

[0035] 3. Add special high-efficiency polymerization inhibitor to prevent material polymerization and improve product yield.

[0036] 4. The tertiary amine hydrochloride produced by the reaction has a high density and settles at the bottom of the reactor. It is separated while reacting, maintaining a homogeneous reaction, reducing side reactions, and improving product purity and yield.

[0037] 5. The tertiary amine hydrochloride is taken out of the system through the sedimentation continuous filtration and washing device. After filtration and separation, the tertiary amine hydrochloride directly enters the neutralization kettle to react with liquid alkali to replace the tertiary amine, realizing tertiary amine recovery with a short process and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a process flow chart of vinylene carbonate production.

[0039] Explanation of the reference numerals: 10, liquid distributor; 11, feed port; 12, filtrate feed port; 13, discharge valve; 14, gas phase port; 15, filtrate feed port; B, pipeline mixer; B1, solvent preheater; B2, ethylene chlorocarbonate preheater; B3, tertiary amine preheater; W1, solvent delivery pump; W2, ethylene chlorocarbonate delivery pump; W3, tertiary amine delivery pump; C, reactor; D1, circulating water condenser; D2, chilled water condenser; E, solvent receiving tank; F, intermediate receiving tank; G, desolventizing tower; H, low-pressure desolventizing tower; J, high-pressure desolventizing tower; K1, primary distillation tower; K2, secondary distillation tower; M1, primary melt crystallizer; M2, secondary melt crystallizer; V, vinylene carbonate finished product receiving tank; N , neutralization kettle; N1, liquid alkali tank; P, separator tank; Q, dehydration tower; R, solvent recovery tower; R1, solvent tank; T, tertiary amine recovery tower; T1, tertiary amine tank; 20, slurry inlet; 21, spiral ribbon; 22, stirring shaft; 23, bottom discharge pipe; 24, overflow port; 25, filtrate discharge outlet 1; 26, filtrate discharge outlet 2; 27, filtrate discharge outlet 3; 28, filtrate discharge outlet 4; 29, washing solvent inlet 1; 30, washing solvent inlet 2; 31, slag slurry discharge valve; 32, jacket; A, sedimentation type continuous filtration and washing device; A-1, sedimentation section; A-2, washing section 1; A-2', washing section 2; A-3, filter drying section; W4, slurry delivery pump; W5, washing solvent delivery pump; W6, circulation pump. DETAILED DESCRIPTION

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0041] A production process for vinylene carbonate comprises the following steps:

[0042] S1: The solvent is continuously fed through the preheater and into the reactor C by controlling the flow rate through the solvent delivery pump W1 and the flow meter; when the solvent feed reaches a certain mass, warm water or steam is introduced into the jacket of the reactor C to preheat and keep the solvent warm;

[0043] When the solvent in the reactor C reaches a certain temperature, the flow rate is controlled by the delivery pumps W1, W2, W3 and the flow meter respectively, and the solvent, chloroethylene carbonate and tertiary amine are continuously passed through the preheaters B1, B2, B3 and the pipeline mixer B at a certain flow rate, and are input into the reactor C from the feed port 11 at the top of the reactor C for dechlorination reaction. The reaction heat is removed by the cooling water introduced into the jacket of the reactor C and the evaporation of the solvent in the reactor C. The solvent in the reactor C absorbs the reaction heat and evaporates, and is distilled out from the gas phase port 14 at the top of the reactor C. After being cooled by the circulating water and chilled water two-stage heat exchangers D1 and D2, it is received by the solvent receiving tank E and recycled.

[0044] S2: The slurry in the reactor C is continuously fed from the discharge valve 13 at the bottom of the reactor C into the sedimentation type continuous filtering and washing device A through the slurry delivery pump W4. The tertiary amine hydrochloride by-product generated by the reaction is naturally settled in the sedimentation section A-1 of the sedimentation type continuous filtering and washing device A. The reaction liquid is filtered through the metal sintered filter screen on the shaft wall of the stirring shaft 22 and the spiral ribbon 21 of the sedimentation type continuous filtering and washing device A, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22, and then filtered through the metal sintered filter screen on the cylinder wall of the sedimentation section A-1, and then discharged from the filtrate discharge port 25 of the jacket. The clear liquid passing through the upper part of the cylinder of the sedimentation section A-1 is discharged from the overflow port 24; the settled tertiary amine hydrochloride is discharged downward through the spiral ribbon 21 of the stirring shaft 22 into the washing section A-2 of the sedimentation type continuous filtration and washing device A. The solvent is continuously input from the washing solvent inlets 29 and 30 of the washing section A-2 through the washing solvent delivery pump W5 and the flow meter to control the flow rate, and washes the reaction by-product tertiary amine hydrochloride. The washing liquid is filtered through the shaft wall of the stirring shaft 22 and the metal sintered filter screen of the spiral ribbon 21, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22 and the washing section A- 2. After being filtered by the metal sintered filter screen on the wall of the cylinder, the tertiary amine hydrochloride is discharged from the filtrate outlets 26 and 27 of the jacket; the tertiary amine hydrochloride continues to settle in the washing section A-2 and is discharged downward through the spiral ribbon 21 of the stirring shaft 22 into the filter drying section A-3 of the sedimentation type continuous filtering and washing device A. The washing liquid continues to be filtered by the metal sintered filter screen on the wall of the stirring shaft 22 and the spiral ribbon 21 of the sedimentation type continuous filtering and washing device A, and is discharged through the bottom discharge pipe 23 in the stirring shaft 22, and is filtered by the metal sintered filter screen on the wall of the filter drying section A-3, and is discharged from the filtrate outlet 28 of the jacket; finally, the filtered tertiary amine salt The hydrochloric acid salt is pushed by the spiral ribbon 21 of the filtration and drying section A-3 and discharged from the bottom slag discharge valve 31, and the mixed slurry of tertiary amine hydrochloride and residual solvent is continuously discharged into the neutralization kettle N; the overflow and filtered reaction liquid and washing liquid from the sedimentation section A-1, washing section A-2, and filtration and drying section A-3 are combined and fed into the intermediate receiving tank F through the circulation pump W6 for continuous synthesis; or the filtrate inlet 12 and / or 15 at the upper or middle part of the reactor C is returned to the reactor C for circulation to carry out intermittent synthesis. After the reaction is complete, it is fed into the intermediate receiving tank F through the circulation pump 16;

[0045] S3: The reaction liquid and washing liquid overflowing or filtered from the sedimentation-type continuous filtration and washing device enter the intermediate receiving tank F, and then undergo continuous distillation. The solvent is first separated and recovered in the desolventizing tower G, the low-boiling tower H, and the high-boiling tower J, and then returned to S1 or S2 for synthesis or washing, and the high-boiling substances are removed to obtain crude vinylene carbonate;

[0046] S4: The crude vinylene carbonate is distilled and purified in the primary distillation tower K1 and the secondary distillation tower K2 to obtain the refined vinylene carbonate;

[0047] S5: The vinylene carbonate product passes through the primary melt crystallizer M1 and the secondary melt crystallizer M2 to obtain a vinylene carbonate product with a purity of more than 99.99%, which enters the vinylene carbonate product receiving tank V;

[0048] S6: The tertiary amine hydrochloride slurry discharged from S2 enters the neutralization kettle N, is neutralized by adding liquid caustic soda, and then transferred to the separator P for separation. The upper organic phase enters the dehydration tower Q of the recovery system for dehydration, and then enters the solvent recovery tower R for distillation to recover the solvent, and the tertiary amine recovery tower T for distillation to recover the tertiary amine. The recovered solvent can be returned to S1 or S2 for reuse, and the recovered tertiary amine can be reused in S1;

[0049] S7: The brine separated from the lower layer of the S6 separator tank P passes through a single-effect or multi-effect evaporation system, and the evaporated wastewater enters the sewage treatment system for biochemical treatment; the salt slurry discharged by evaporation is transferred to the rotary kiln of the waste liquid incinerator for high-temperature calcination to remove organic matter, and the obtained sodium chloride is sold as a by-product or treated as general solid waste.

[0050] The tertiary amine is selected from N,N-dimethylethylamine, N,N-dimethyl-n-propylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylhexylamine, N,N-dimethylcyclohexylamine, N,N-dimethylaniline, diethylmethylamine, di-n-propylmethylamine, diisopropylmethylamine, triethylamine, triisopropylamine, tributylamine, pyridine, N-methylpyrrole, N-methylpyrrolidine, N-methylmorpholine, N-methylpiperidine , imidazole, N-methylimidazole, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylbutanediamine, N,N,N',N'-tetramethylhexanediamine, N,N'-dimethylpiperazine, pentamethyldiethylenetriamine, triethylenediamine, 1,5-diazabis[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undec-7-ene or one or more combinations thereof.

[0051] The solvent is a hydrocarbon, ether, ester, or nitrile compound, more typically selected from one or more mixtures of n-hexane, cyclohexane, n-heptane, petroleum ether, dichloromethane, dichloroethane, methyl propyl ether, ethyl propyl ether, methyl tert-butyl ether, n-propyl ether, isopropyl ether, ethyl formate, n-propyl formate, isopropyl formate, n-butyl formate, isobutyl formate, tert-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, methyl propionate, ethyl propionate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and acetonitrile; the density of the solvent or the mixed solvent at 25° C. is less than 1.0; the solvent contains 0.01 to 0.5% polymerization inhibitor, the polymerization inhibitor is a combination of one or more of phenols, quinones, phenothiazines, phosphites, piperidinols, and piperidine nitrogen oxides. Typical polymerization inhibitors are one or more of hydroquinone, p-methoxyphenol, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,5-di-tert-butylhydroquinone, phenothiazine, 2,2,6,6-tetramethyl-4-hydroxy-piperidine nitrogen oxide, tris(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) phosphite, and bis(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) sebacate.

[0052] The mass ratio of the solvent, ethylene chlorocarbonate and tertiary amine is 2.0-10.0:1.0:0.8-1.5; the reaction temperature is controlled at 50-100° C.; the residence time of the ethylene chlorocarbonate and the tertiary amine in the reactor C for the dechlorination reaction is 1-16 hours, and the dechlorination reaction is carried out.

[0053] Temperature measuring devices are installed on the pipelines connecting the rear ends of preheaters B1, B2, and B3 for the solvent, ethylene chloride, and tertiary amine, and the front end of pipeline mixer B. Temperature measuring devices are also installed at the top, middle, and bottom of reactor C. These devices are interlocked with flowmeters and controlled via the DCS control room. If the measured temperature of the materials in reactor C exceeds the reaction temperature range, heat exchange is performed through the reactor C jacket, while the feed flow rate or the preheating temperature of the raw materials needs to be reduced.

[0054] A vinylene carbonate production device, comprising: a solvent delivery pump W1, a chloroethylene carbonate delivery pump W2, a tertiary amine delivery pump W3, a solvent preheater B1, a chloroethylene carbonate preheater B2, a tertiary amine preheater B3, a pipeline mixer B, a reactor C, a circulating water condenser D1, a chilled water condenser D2, a solvent receiving tank E, an intermediate receiving tank F, a desolventizing tower G, a low-pressure desolventizing tower H, a high-pressure desolventizing tower J, a primary distillation tower K1, a secondary distillation tower K2, a primary melt crystallizer M1, and a secondary melt crystallizer M2, vinylene carbonate finished product receiving tank V, also includes a sedimentation type continuous filtering and washing device A, which is connected to the discharge valve 13 at the bottom of the reactor C. The sedimentation type continuous filtering and washing device A includes three cylindrical parts: sedimentation section A-1, washing section A-2 and drying section A-3, which are connected in sequence; the slurry discharge valve 31 at the bottom of the drying section A-3 is connected to the neutralization kettle N, liquid alkali tank N1, separator tank P, dehydration tower Q, solvent recovery tower R, solvent tank R1, tertiary amine recovery tower T, and tertiary amine tank T1.

[0055] A feed port 11 is provided at the center of the top of the reactor C. The feed pipe 11 extends into the interior of the reactor C and is connected to a liquid distributor 10. The liquid distributor plane is installed and fixed parallel to the cross section of the reactor C. The feed port 11 is connected to the pipeline from the pipeline mixer B. A gas phase port 14 is provided on the upper part of the reactor C, which is connected to the circulating water condenser D1 and the chilled water condenser D2. A filtrate feed port 12 is also provided on the upper part of the cylinder wall of the reactor C, which is connected to the circulating pump W6. A discharge valve 13 is provided at the bottom of the reactor C. The discharge valve 13 is an automatic switching valve, connected to the slurry inlet 20 of the sedimentation continuous filtration and washing device A; a filtrate inlet 15 is provided in the middle of the reactor C, connected to the circulation pump W6; the diameter of the liquid distributor 10 is 100 to 2000 mm; the diameter of the cylinder of the reactor C is 500 to 4000 mm, and the height of the cylinder is 1000 to 10000 mm; the outside of the reactor C is provided with a jacket, through which a heat exchange medium is introduced, and the heat exchange medium includes but is not limited to steam, thermal oil, chilled water, and circulating water.

[0056] The sedimentation section A-1, washing section A-2, and filter section A-3 of the sedimentation type continuous filtering and washing device A are provided with a stirring shaft 22 inside the cylinder. The upper part of the stirring shaft 22 is driven by a motor M through a reducer. The stirring shaft 22 is a hollow shaft. A spiral ribbon 21 is installed on the stirring shaft 22. The spiral ribbon 21 is a hollow structure. A bottom discharge pipe 23 is provided inside the stirring shaft 22. The top of the bottom discharge pipe 23 is connected to the filtrate pipeline. The shaft wall of the stirring shaft 22 and the spiral ribbon 21 can be fully or partially a three-layer composite plate with a metal sintered filter mesh sandwiched between two layers of perforated plates. The hollow inner cavity of the stirring shaft 22 and the spiral ribbon 21 are connected. The inner cavity of the belt 21 is connected; the filtrate is filtered into the inner cavity through the shaft wall of the stirring shaft 22 and the composite plate of the spiral ribbon 21, and is discharged through the top outlet of the bottom discharge pipe 23 in the stirring shaft 22; the bottom end of the stirring shaft 22 is a solid shaft, and is fixed and supported by a sleeve or a bearing; if necessary, the middle part of the stirring shaft 22, that is, the connection between the three parts of the cylinder of the sedimentation section A-1, the washing section A-2, and the drying section A-3, can be fixed with several bearings or sleeves; the speed of the stirring shaft 22 can be adjusted by a reducer and a frequency converter according to the solid content of the slurry; the spiral ribbon 21 can be a segmented or broken line continuous spiral ribbon.

[0057] The upper part of the sedimentation section A-1 cylinder is provided with a slurry inlet 20, which is connected to the discharge valve 13 at the bottom of the reactor C. The upper part of the sedimentation section A-1 cylinder is provided with an overflow port 24 for the settled clarified reaction liquid, and the lower part is provided with a filtrate discharge port 25; the washing section A-2 can be composed of one or more sections of cylinders, and the upper part of the outer wall of the jacket of each section of the cylinder is provided with a washing solvent inlet 29, 30, and the lower part is provided with a filtrate discharge port 26, 27; the jacket of the filtration section A-3 cylinder A filtrate discharge outlet 28 is provided at the lower part of the outer wall; the cylinder wall of the sedimentation section A-1, washing section A-2 and filtering section A-3 can be a single-layer structure or a double-layer jacket structure; the inner wall of the double-layer jacket structure is a three-layer composite plate with a metal sintered filter mesh sandwiched between two layers of perforated plates, and the outer wall of the jacket is a solid steel plate; the lower part of the cylinder of the filtering section A-3 is equipped with a sleeve or bearing supporting the stirring shaft 22, and the bottom outlet is equipped with a slurry discharge valve 31 with automatic opening and closing or adjustment functions.

[0058] The material of the three-part cylinder of the sedimentation section A-1, the washing section A-2, and the filtering section A-3 is one of carbon steel, glass lining, stainless steel, steel lined with plastic, steel sprayed with plastic, titanium, and alloy steel; the material of the stirring shaft 19 and the spiral ribbon 21 is one of carbon steel, stainless steel, titanium, and alloy steel metal materials; the cylinder wall, stirring shaft, and spiral ribbon of the three-part cylinder of the sedimentation section A-1, the washing section A-2, and the filtering section A-3 are not solid structures at the same time.

[0059] Example

[0060] This embodiment is used to illustrate a process flow chart of vinylene carbonate production according to the present invention. Figure 1 shown.

[0061] This embodiment is used to illustrate a vinylene carbonate production device according to the present invention. Figure 1 The dimensions of the production device of this embodiment are as follows: the diameter of the reactor C is 1600 mm, the head is elliptical, the height of the cylinder is 2400 mm, the diameter of the liquid distributor 10 inside the reactor C is 800 mm, and the liquid distributor 10 is located 200 mm above the upper cross section of the cylinder of the reactor C.

[0062] The sedimentation section A-1 of the sedimentation-type continuous filtering and washing device has a height of 1800 mm and a diameter of 800 mm; washing sections A-2 and A-2' are set, and the height of the two washing sections is 800 mm and the diameter is 800 mm; the height of the drying section A-3 is 1200 mm and the diameter is 800 mm.

[0063] S1: Isopropyl ether and methyl acetate were mixed in a volume ratio of 2:1, and a mixed organic solvent containing 0.3% 2,5-di-tert-butylhydroquinone and 0.1% p-methoxyphenol as a polymerization inhibitor was dissolved therein. The mixed organic solvent was heated to 60°C in a solvent preheater B1 via solvent delivery pump W1 and then fed into reactor C. A total of 2700 kg was fed, and W1 feeding was stopped.

[0064] Warm water at 70°C was passed into the jacket of reactor C to maintain the temperature of the organic solvent in reactor C at 60-65°C.

[0065] The slurry delivery pump W4 is started to circulate the mixed solvent in the reactor C through the sedimentation-type continuous filtration and washing device A, the circulation pump W6, and the filtrate feed port 12.

[0066] Start the ethylene chlorocarbonate and triethylamine delivery pumps W1, W2 and W3 at the same time, at flow rates of 90 kg / h and 80 kg / h respectively, preheat the mixed solvent, ethylene chlorocarbonate and triethylamine to 60°C through preheaters B1, B2 and B3 respectively, and then combine and pass through the pipeline mixer B from the feed port 11 of the reactor C through the liquid distributor 10 and evenly input into the reactor C.

[0067] The reaction is exothermic, and the solvent in the reactor C absorbs the reaction heat and evaporates, then evaporates from the gas phase port 14 at the top of the reactor C, is cooled by the circulating water condenser D1 and the chilled water condenser D2, is received by the solvent receiving tank E, and is reused in S1. At the same time, the temperature in the reactor C is controlled by adjusting the flow rate of the circulating cooling water introduced into the jacket of the reactor C, so as to maintain the reaction temperature in the reactor C at 60-70°C.

[0068] S2: The slurry in the reactor C is continuously input into the sedimentation type continuous filtering and washing device A through the discharge valve 13 from the bottom of the reactor C and the slurry delivery pump W4. The tertiary amine hydrochloride by-product generated by the reaction naturally settles in the sedimentation section A-1 of the sedimentation type continuous filtering and washing device A, and the reaction liquid is filtered through the metal sintered filter screen on the shaft wall of the stirring shaft 22 and the spiral belt 21 of the sedimentation type continuous filtering and washing device A, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22, and then filtered through the metal sintered filter screen on the cylinder wall of the sedimentation section A-1 and discharged from the filtrate discharge port 25 of the jacket, and the clear liquid on the upper part of the cylinder of the sedimentation section A-1 is discharged from the overflow port 24; the settled tertiary amine hydrochloride is discharged downward through the spiral belt 21 of the stirring shaft 22 into the washing section A-2 of the sedimentation type continuous filtering and washing device A.

[0069] When the cumulative feed amount of ethylene chlorocarbonate reaches 900 kg, the reaction liquid sample is taken for gas chromatography analysis, and the ethylene chlorocarbonate content drops to 0.3%. The filtrate feed port 12 is closed, and the material output by the circulation pump W6 is switched to the intermediate receiving tank F for reception. At the same time, the solvent delivery pump W1 is started and continuously input into the reactor C at a flow rate of 220 kg / h.

[0070] Isopropyl ether is continuously fed through the washing solvent delivery pump W5 and the flow meter at a flow rate of 200 kg / h, and is fed from the washing solvent inlets 29 and 30 of the washing section A-2 to wash the reaction by-product tertiary amine hydrochloride. The washing liquid is filtered through the shaft wall of the stirring shaft 22 and the metal sintered filter screen of the spiral ribbon 21, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22. It is also filtered through the metal sintered filter screen on the barrel wall of the washing section A-2 and then discharged from the filtrate discharge ports 26 and 27 of the jacket. The tertiary amine hydrochloride continues to settle in the washing section A-2 and is discharged downward through the spiral ribbon 21 of the stirring shaft 22 into the filter drying section A-3 of the sedimentation type continuous filtration and washing device A. The washing liquid continues to settle. After being filtered through the metal sintered filter screen on the shaft wall of the stirring shaft 22 and the spiral ribbon 21 of the sedimentation-type continuous filtration and washing device A, the liquid is discharged through the bottom discharge pipe 23 in the stirring shaft 22, filtered through the metal sintered filter screen on the wall of the drying section A-3, and discharged from the filtrate outlet 28 of the jacket. Finally, the filtered tertiary amine hydrochloride is pushed by the spiral ribbon 21 of the drying section A-3 and discharged from the bottom slag discharge valve 31. The mixed slurry of tertiary amine hydrochloride and residual solvent is continuously discharged into the neutralization kettle N. The overflow from the sedimentation section A-1, washing section A-2, and drying section A-3 and the filtered reaction liquid and washing liquid are combined and input into the intermediate receiving tank F via a circulation pump W6.

[0071] S3: The reaction liquid and washing liquid overflowing and filtered from the sedimentation-type continuous filtration and washing unit A enter intermediate receiving tank F, where they undergo continuous distillation. The solvent mixture of methyl acetate and isopropyl ether is removed via a desolventizing column, low-boiling products such as triethylamine and isopropyl ether are removed via a low-boiling column, and high-boiling polymers are removed via a high-boiling column. This yields crude vinylene carbonate, which, according to gas chromatography, contains 92.2% vinylene carbonate. The solvent and triethylamine are condensed and recovered, entering the solvent and triethylamine storage tanks, respectively, for repeated use in S1 or S2.

[0072] S4: The crude vinylene carbonate obtained in S3 is continuously distilled through a primary distillation tower K1 and a secondary distillation tower K2 to obtain refined vinylene carbonate. Gas chromatography analysis shows that the purity of the vinylene carbonate is 99.63%.

[0073] S5: The vinylene carbonate product is sequentially passed through a primary melt crystallizer and a secondary melt crystallizer to obtain a finished vinylene carbonate product. Gas chromatography analysis shows that the purity of the vinylene carbonate reaches 99.996%.

[0074] S6: The solvent slurry of triethylamine hydrochloride discharged from S2 enters a sedimentation-type continuous filtration and washing device, is filtered through the inner wall of each part of the cylinder, the shaft wall of the stirring shaft 22, and the composite plate of the spiral ribbon 21, enters the cylinder jacket or the inner cavity of the stirring shaft 22 and the spiral ribbon 21, and is discharged through the cylinder jacket filtrate discharge ports 26, 27, 28 and the top outlet of the bottom discharge pipe 23 in the stirring shaft 22, bringing the vinylene carbonate product entrained in the tertiary amine hydrochloride slurry into the reaction solution and washing away the polymer entrained in the tertiary amine hydrochloride; the filter residue is discharged from the bottom of the cylinder of the filtration and drying section A-3 with an automatically opened and closed or adjustable slurry discharge valve 31;

[0075] S7: The slurry obtained in S6 is treated with 32% liquid caustic soda in a neutralization kettle, and the pH value of the aqueous phase is adjusted to 9-11. The slurry is then transferred to a separatory tank P for stratification. The upper organic phase containing isopropyl ether and triethylamine is sequentially distilled and separated through a dehydration tower Q, a solvent recovery tower P, and a tertiary amine recovery tower Q. The recovered isopropyl ether has a purity of 99.2% and a moisture content of 120 ppm; the recovered triethylamine has a purity of 99.2% and a moisture content of 190 ppm, and can be fully reused in S1 and S2.

[0076] S8: The brine separated from the lower layer of the separator tank P passes through a single-effect or multi-effect evaporation system, and the evaporated wastewater enters the sewage treatment system for biochemical treatment; the salt slurry discharged by evaporation is transferred to the rotary kiln of the solid waste incinerator for high-temperature calcination to remove organic matter, and the obtained sodium chloride is sold as a by-product or treated as general solid waste.

[0077] The present invention provides a vinylene carbonate production process and apparatus, which can not only effectively improve the purity and yield of the product and stabilize the product characteristics, but also reduce equipment investment and labor costs, lower production energy consumption, and have low production costs, and can be applied to the large-scale production of vinylene carbonate.

[0078] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. The above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A process for producing vinylene carbonate, characterized in that: Production process The following steps are involved: S1: The solvent is continuously fed through the preheater B1 and into the reactor C through the flow rate controlled by the solvent delivery pump W1 and the flow meter; when the solvent feed reaches a certain volume, warm water or steam is introduced into the jacket of the reactor C to preheat and keep the solvent warm; When the solvent in the reactor C reaches a certain temperature, the flow rate is controlled by the delivery pumps W1, W2, W3 and the flow meter respectively, and the solvent, chloroethylene carbonate and tertiary amine are continuously passed through the preheaters B1, B2, B3 and the pipeline mixer B at a certain flow rate, and are input into the reactor C from the feed port 11 at the top of the reactor C for dechlorination reaction. The reaction heat is removed by the cooling water introduced into the jacket of the reactor C and the evaporation of the solvent in the reactor C. The solvent in the reactor C absorbs the reaction heat and evaporates, and is distilled out from the gas phase port 14 at the top of the reactor C. After being cooled by the circulating water and chilled water two-stage heat exchangers D1 and D2, it is received by the solvent receiving tank E and recycled. S2: The slurry in the reactor C is continuously fed into the sedimentation type continuous filtering and washing device A from the discharge valve 13 at the bottom of the reactor C through the slurry delivery pump W4, or flows into the sedimentation type continuous filtering and washing device A through high head difference gravity; the by-product tertiary amine hydrochloride generated by the reaction is naturally settled in the sedimentation section A-1 of the sedimentation type continuous filtering and washing device A, and the reaction liquid is filtered through the metal sintered filter screen of the shaft wall of the stirring shaft 22 and the spiral ribbon 21 of the sedimentation type continuous filtering and washing device A, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22, and filtered through the metal sintered filter screen of the cylinder wall of the sedimentation section A-1. The filtrate is discharged from the jacket outlet 25, and the clear liquid passing through the upper part of the cylinder of the sedimentation section A-1 is discharged from the overflow port 24; the settled tertiary amine hydrochloride is discharged downward through the spiral ribbon 21 of the stirring shaft 22 into the washing section A-2 of the sedimentation type continuous filtration and washing device A. The solvent is controlled by the washing solvent delivery pump W5 and the flow meter, and is continuously input from the washing solvent inlets 29 and 30 of the washing section A-2 to wash the reaction by-product tertiary amine hydrochloride. The washing liquid is filtered through the shaft wall of the stirring shaft 22 and the metal sintered filter screen of the spiral ribbon 21, and then discharged through the bottom discharge pipe 23 in the stirring shaft 22 and the bottom discharge pipe 23 in the stirring shaft 22. The washing liquid is filtered through the metal sintered filter screen on the wall of the washing section A-2 and then discharged from the filtrate outlets 26 and 27 of the jacket; the tertiary amine hydrochloride continues to settle in the washing section A-2 and is discharged downward through the spiral ribbon 21 of the stirring shaft 22 into the filter section A-3 of the sedimentation type continuous filtering washing device A. The washing liquid continues to be filtered through the metal sintered filter screen on the wall of the stirring shaft 22 and the spiral ribbon 21 of the sedimentation type continuous filtering washing device A and then is discharged through the bottom discharge pipe 23 in the stirring shaft 22, filtered through the metal sintered filter screen on the wall of the filter section A-3 and then discharged from the filtrate outlet 28 of the jacket; finally, the filtered tertiary amine hydrochloride is discharged through The spiral ribbon 21 of the filtration section A-3 pushes the discharge valve 31 at the bottom to discharge the mixed slurry of tertiary amine hydrochloride and residual solvent continuously into the neutralization kettle N; the overflow and filtered reaction liquid and washing liquid from the sedimentation section A-1, washing section A-2, and filtration section A-3 are combined and continuously input into the intermediate receiving tank F through the circulation pump W6 to achieve continuous synthesis; or the filtrate feed port 12 and / or the filtrate feed port 15 at the top of the reactor C are returned to the reactor C for circulation to perform intermittent synthesis. After the reaction is complete, the filtrate feed ports 12 and 15 are closed and the feed is switched to the intermediate receiving tank F for reception; S3: The reaction liquid received in the intermediate receiving tank F is continuously distilled, first separated and recovered by the desolventizing tower G, the low-boiling tower H, and the high-boiling tower J, and then returned to S1 or S2 for synthesis or washing, and the high-boiling substances are removed to obtain crude vinylene carbonate; S4: The crude vinylene carbonate is distilled and purified in the primary distillation tower K1 and the secondary distillation tower K2 to obtain the refined vinylene carbonate; S5: The vinylene carbonate product is melt-crystallized in the primary melt crystallizer M1 and the secondary melt crystallizer M2 to obtain a vinylene carbonate product with a purity of more than 99.99%, which enters the vinylene carbonate product receiving tank V; S6: The tertiary amine hydrochloride slurry discharged from S2 enters the neutralization kettle N, is neutralized by adding liquid caustic soda, and then transferred to the separator P for stratification. The upper organic phase enters the dehydration tower Q of the recovery system for dehydration, and then enters the solvent recovery tower R for distillation to recover the solvent, and the tertiary amine recovery tower T for distillation to recover the tertiary amine. The recovered solvent can be returned to S1 and reused in S2, and the recovered tertiary amine can be reused in S1; S7: The brine separated from the lower layer of the S6 separator tank P passes through a single-effect or multi-effect evaporation system, and the evaporated wastewater enters the sewage treatment system for biochemical treatment; the salt slurry discharged by evaporation is transferred to the rotary kiln of the waste liquid incinerator for high-temperature calcination to remove organic matter, and the obtained sodium chloride is sold as a by-product or treated as general solid waste.

2. A vinylene carbonate production device, characterized in that: The production device includes: a solvent delivery pump W1, a chloroethylene carbonate delivery pump W2, a tertiary amine delivery pump W3, a solvent preheater B1, a chloroethylene carbonate preheater B2, a tertiary amine preheater B3, a pipeline mixer B, a reactor C, a circulating water condenser D1, a chilled water condenser D2, a solvent receiving tank E, an intermediate receiving tank F, a desolventizing tower G, a low-pressure desolventizing tower H, a high-pressure desolventizing tower J, a primary distillation tower K1, a secondary distillation tower K2, a primary melting crystallizer M1, a secondary melting crystallizer M2, a vinylene carbonate finished product receiving tank V, and also includes a sedimentation continuous filtration Washing device A, the sedimentation type continuous filtering washing device A is connected to the discharge valve 13 at the bottom of the reactor C through a slurry delivery pump W4 or directly through a high head difference. The sedimentation type continuous filtering washing device A includes three cylindrical parts: a sedimentation section A-1, a washing section A-2, and a drying section A-3, which are combined and connected in sequence; the slurry discharge valve 31 at the bottom of the drying section A-3 is connected to the neutralization kettle N, the liquid alkali tank N1, the separator tank P, the dehydration tower Q, the solvent recovery tower R, the solvent tank R1, the tertiary amine recovery tower T, and the tertiary amine tank T1.

3. A process for producing vinylene carbonate according to claim 1, characterized in that: The tertiary amine is selected from N,N-dimethylethylamine, N,N-dimethyl-n-propylamine, N,N-dimethylisopropylamine, N,N-dimethylbutylamine, N,N-dimethylhexylamine, N,N-dimethylcyclohexylamine, N,N-dimethylaniline, diethylmethylamine, di-n-propylmethylamine, diisopropylmethylamine, triethylamine, triisopropylamine, tributylamine, pyridine, N-methylpyrrole, N-methylpyrrolidine, N-methylmorpholine, N-methylpiperidin, One or more combinations of 1,5-diazabis[4.3.0]non-5-ene and 1,8-diazabicyclo[5.4.0]undec-7-ene.

4. A process for producing vinylene carbonate according to claim 1, characterized in that: The solvent is a hydrocarbon, ether, ester, or nitrile compound, and is more typically selected from one or more mixtures of n-hexane, cyclohexane, n-heptane, petroleum ether, dichloromethane, dichloroethane, methyl propyl ether, ethyl propyl ether, methyl tert-butyl ether, n-propyl ether, isopropyl ether, ethyl formate, n-propyl formate, isopropyl formate, n-butyl formate, isobutyl formate, tert-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, methyl propionate, ethyl propionate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and acetonitrile; the density of the solvent or mixed solvent at 25° C. is less than 1.0; the solvent contains 0.0 1 to 0.5% of a polymerization inhibitor, wherein the polymerization inhibitor is a combination of one or more of phenols, quinones, phenothiazines, phosphites, piperidinols, and piperidine nitrogen oxides. Typical polymerization inhibitors are a combination of one or more of hydroquinone, p-methoxyphenol, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,5-di-tert-butylhydroquinone, phenothiazine, 2,2,6,6-tetramethyl-4-hydroxy-piperidine nitrogen oxide, tris(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) phosphite, and bis(2,2,6,6-tetramethyl-4-oxy-piperidine nitrogen oxide) sebacate.

5. A process for producing vinylene carbonate according to claim 1, characterized in that: The mass ratio of the solvent, ethylene chloride and tertiary amine is 2.0-10.0:1.0:0.8-1.5; the reaction temperature is controlled at 50-100° C.; the residence time of the ethylene chloride and tertiary amine in the reactor C for the dechlorination reaction is 1-16 hours to carry out the dechlorination reaction.

6. A process for producing vinylene carbonate according to claim 1, characterized in that: The outlets of the preheaters B1, B2, and B3 for the solvent, ethylene chloride, and tertiary amine are all equipped with temperature measuring devices; temperature measuring devices are installed at the upper, middle, and lower parts of the liquid distributor 10; a temperature measuring device is installed on the side wall of the reactor C; the temperature measuring device is interlocked with the flow meter in the DCS control room.

7. The production device of vinylene carbonate according to claim 2, characterized in that: The top of the reactor C is provided with a feed port 11, the feed port 11 pipe extends into the interior of the reactor C, and is connected to a liquid distributor 10, so that the feed liquid is evenly distributed along the cross section of the reactor C and added to the reactor C; the feed port 11 is connected to the pipeline mixer B; the upper part of the reactor C is provided with a gas phase port 14, which is connected to the circulating water condenser D1 and the chilled water condenser D2; the upper part of the cylinder of the reactor C is also provided with a filtrate feed port 12, which is connected to the circulating pump W6; the bottom of the reactor C is provided with a discharge valve 13, which is an automatic switch The reactor C is provided with a slurry inlet 20, which is connected to the slurry inlet of the sedimentation continuous filtration and washing device A through a slurry delivery pump W4 or directly through a high head difference; a filtrate feed port 15 is provided in the middle of the reactor C, which is connected to the circulation pump W6; the diameter of the liquid distributor 10 is 100 to 2000 mm; the diameter of the cylinder of the reactor C is 500 to 4000 mm, and the height of the cylinder is 1000 to 10000 mm; a jacket is provided on the outside of the reactor C, through which a heat exchange medium is introduced, and the heat exchange medium includes but is not limited to steam, thermal oil, chilled water, and circulating water.

8. The vinylene carbonate production device according to claim 2, characterized in that: The sedimentation section A-1, washing section A-2 and filter section A-3 of the sedimentation type continuous filtering and washing device A are provided with a stirring shaft 22 inside the cylinder. The upper part of the stirring shaft 22 is driven by a motor M through a reducer. The stirring shaft 22 is a hollow shaft. A spiral ribbon 21 is installed on the stirring shaft 22. The spiral ribbon 21 is a hollow structure. A bottom discharge pipe 23 is provided inside the stirring shaft 22. The top end of the bottom discharge pipe 23 is connected to the filtrate pipeline. The shaft wall and the spiral ribbon (21) of the stirring shaft 22 can be fully or partially a three-layer composite plate with a metal sintered filter screen sandwiched between two layers of perforated plates. The hollow inner cavity of the stirring shaft 22 is connected to the bottom discharge pipe 23. The inner cavity of the spiral ribbon 21 is connected; the filtrate is filtered into the inner cavity through the shaft wall of the stirring shaft 22 and the composite plate of the spiral ribbon 21, and is discharged through the top outlet of the bottom discharge pipe 23 in the stirring shaft 22; the bottom end of the stirring shaft 22 is a solid shaft, and is fixed and supported by a sleeve or a bearing; if necessary, the middle part of the stirring shaft 22, that is, the connection between the three parts of the cylinder of the sedimentation section A-1, the washing section A-2, and the drying section A-3, can be fixed with several bearings or sleeves; the rotation speed of the stirring shaft 22 can be adjusted by a reducer and a frequency converter according to the solid content of the slurry; the spiral ribbon 21 can be a segmented or broken line continuous spiral ribbon.

9. The vinylene carbonate production device according to claim 2, characterized in that: A slurry inlet 20 is provided in the middle of the cylinder of the sedimentation section A-1, and the slurry inlet 20 is connected to the discharge valve 13 at the bottom of the reactor C through a slurry delivery pump W4 or directly through a high head difference. An overflow port 24 for the settled clarified reaction liquid is provided on the upper part of the cylinder of the sedimentation section A-1, and a filtrate discharge port 25 is provided on the lower part of the outer wall of the jacket; the washing section A-2 can be composed of one or more sections of the cylinder, and the upper part of each section of the cylinder is provided with a washing solvent inlet 29, 30, and the lower part of the outer wall of the jacket is provided with a filtrate discharge port 26, 27; A filtrate discharge outlet 28 is provided at the lower part of the outer wall of the jacket of the drying section A-3 cylinder; the cylinder walls of the sedimentation section A-1, washing section A-2 and drying section A-3 can be a single-layer structure or a double-layer jacket structure; the inner wall of the double-layer jacket structure is a three-layer composite plate with a metal sintered filter mesh sandwiched between two layers of perforated plates, and the outer wall of the jacket is a solid steel plate; the lower part of the drying section A-3 cylinder is equipped with a sleeve or bearing supporting the stirring shaft 22, and the bottom outlet is equipped with a pulp and slag discharge valve 31 with automatic opening and closing or adjustment functions.

10. The vinylene carbonate production device according to claim 9, characterized in that: The material of the three-part cylinder of the sedimentation section A-1, the washing section A-2, and the filtering section A-3 is one of carbon steel, glass lining, stainless steel, steel lined with plastic, steel sprayed with plastic, titanium, and alloy steel; the material of the stirring shaft 19 and the spiral belt 21 is one of carbon steel, stainless steel, titanium, and alloy steel metal materials; the cylinder wall, stirring shaft, and spiral belt of the three-part cylinder of the sedimentation section A-1, the washing section A-2, and the filtering section A-3 are not solid structures at the same time.

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