Production system of methylene methyldisulfonate

Abstract

The utility model belongs to the technical field of methylene methyldisulfonate production, and particularly relates to a methylene methyldisulfonate production system which comprises an esterification kettle, an extraction tank, a primary centrifugal machine, a crystallization kettle, a secondary centrifugal machine and a spiral conveyor which are sequentially connected, and the top of the extraction tank and the top of the crystallization kettle are both connected to a dichloromethane elevated tank; the top of the extraction tank is further connected to a tube pass upper opening of the condenser through a pipeline, a tube pass lower opening of the condenser is connected to a liquid inlet of the esterification kettle through a pipeline, a liquid discharging opening of the primary centrifugal machine is connected to a primary mother liquor tank, and a liquid discharging opening of the secondary centrifugal machine is connected to a secondary mother liquor tank. The production system is reasonable in structural arrangement, methylene methyldisulfonate in the esterification liquid is extracted by using dichloromethane instead of water, the output of wastewater is greatly reduced, severe heat release is avoided in the treatment process, and the safety risk is greatly reduced.

Description

Technical Field

[0001] This utility model belongs to the technical field of methyl disulfonate production, specifically a methyl disulfonate production system. Background Technology

[0002] Batteries with added methylene disulfonate (MMDS) exhibit excellent high-temperature cycle performance and are suitable for power batteries, especially those using lithium manganese oxide as the positive electrode material. MMDS prevents the adsorption of molten manganese (Mn) on the negative electrode surface at high temperatures, suppressing impedance rise and effectively improving cycle characteristics, thus significantly increasing cycle life. Furthermore, methylene disulfonate can be used as a pharmaceutical preparation for treating leukemia and other diseases in animals.

[0003] Currently, the industrial production process of methylene disulfonate involves esterification of methylene disulfonic acid and paraformaldehyde with phosphorus pentoxide as a dehydrating agent. The post-treatment involves adding a large amount of ice water to the esterification liquid to quench the metaphosphoric acid and pyrophosphoric acid generated in the reaction, which releases a large amount of heat, makes it difficult to control the system temperature, and generates a large amount of wastewater. This production process does not meet the requirements of green environmental protection. Utility Model Content

[0004] To address the problems mentioned above, this invention provides a production system for methylene disulfonate. This system uses dichloromethane to extract methylene disulfonate from the esterification liquid during post-treatment, which significantly reduces wastewater generation.

[0005] The technical solution of this utility model is as follows:

[0006] A production system for methylene disulfonate includes an esterification vessel, an extraction tank, a primary centrifuge, a crystallization vessel, a secondary centrifuge, and a screw conveyor connected in sequence, wherein:

[0007] The top of the extraction tank and the top of the crystallization vessel are both connected to the high-level dichloromethane tank; the top of the extraction tank is also connected to the upper tube end of the condenser via a pipe, and the lower tube end of the condenser is connected to the liquid inlet of the esterification vessel via a pipe.

[0008] The solid discharge port of the primary centrifuge is connected to the crystallization kettle via an elevator, and the liquid discharge port of the primary centrifuge is connected to the primary mother liquor tank; the solid discharge port of the secondary centrifuge is connected to the screw conveyor, and the liquid discharge port of the secondary centrifuge is connected to the secondary mother liquor tank.

[0009] Furthermore, the outlet of the esterification vessel is connected to the inlet of the extraction tank through a first pipe, and an inverted U-shaped buffer section is provided on the first pipe.

[0010] Furthermore, the inlet end of the buffer tube section is connected to the outlet of the esterification vessel via a first bent pipe, and the outlet end of the buffer tube section is connected to the inlet of the extraction tank via a second bent pipe.

[0011] Furthermore, the primary mother liquor tank is connected to the top of the extraction tank via a second pipe, on which a first magnetic pump is installed; the secondary mother liquor tank is connected to the top of the crystallization vessel via a third pipe, on which a second magnetic pump is installed.

[0012] Furthermore, it also includes a vacuum dryer, the inlet of which is connected to the outlet of a screw conveyor.

[0013] Furthermore, a spiral stirrer is installed inside the esterification reactor.

[0014] Furthermore, the top of the extraction tank is connected to the high-level dichloromethane tank via a fourth pipe, which is equipped with a first valve; the top of the crystallization vessel is connected to the high-level dichloromethane tank via a fifth pipe, which is equipped with a second valve.

[0015] Furthermore, the crystallization vessel is positioned diagonally above the centrifuge, and the elevator is tilted at an angle of 15°-30°.

[0016] Furthermore, a gas-liquid separator is installed on the pipeline between the lower end of the tube side of the condenser and the liquid inlet of the esterification vessel. The liquid outlet of the gas-liquid separator is connected to the liquid inlet of the esterification vessel, and the gas outlet of the gas-liquid separator is connected to the exhaust gas treatment system.

[0017] Furthermore, the dichloromethane high-level tank is located above the crystallization vessel and the extraction tank.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] (1) The production system for methyl disulfonate of this utility model includes an esterification kettle, an extraction tank, a primary centrifuge, a crystallization kettle, a secondary centrifuge, and a screw conveyor connected in sequence. The top of the extraction tank and the top of the crystallization kettle are both connected to a high-level dichloromethane tank. The top of the extraction tank is also connected to the upper end of the tube side of the condenser through a pipe, and the lower end of the tube side of the condenser is connected to the liquid inlet of the esterification kettle through a pipe. The above structure enables the use of dichloromethane instead of water to extract methyl disulfonate from the esterification liquid, which greatly reduces the amount of wastewater generated and does not generate heat violently during the treatment process, thus greatly reducing the safety risk.

[0020] (2) The outlet of the esterification vessel of this invention is connected to the inlet of the extraction tank through a first pipe. The first pipe is equipped with an inverted U-shaped buffer section. The inverted U-shaped buffer section utilizes the principles of solvent reflux and siphon to ensure that the solid substance is continuously extracted by pure solvent, which saves solvent and achieves a high extraction rate. By setting the inverted U-shaped buffer section, the consumption of dichloromethane can be reduced, the residue of acidic impurities can be greatly reduced, the product yield can be increased, and the product quality can be improved, which is in line with the concept of environmental protection and development. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is an overall structural diagram of the production system for methylene disulfonate of this utility model;

[0023] Among them: 1-Esterification kettle, 2-Extraction tank, 3-Primary centrifuge, 4-Crystallization kettle, 5-Secondary centrifuge, 6-Screw conveyor, 7-Elevator, 8-Dichloromethane high-level tank, 9-Condenser, 10-Primary mother liquor tank, 11-Secondary mother liquor tank, 12-First pipeline, 121-Buffer section, 122-First bend pipe, 123-Second bend pipe, 13-Second pipeline, 14-First magnetic pump, 15-Third pipeline, 16-Second magnetic pump, 17-Vacuum dryer, 18-Screw mixer, 19-Fourth pipeline, 20-First valve, 21-Fifth pipeline, 22-Second valve. Detailed Implementation

[0024] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0025] The following is in conjunction with the appendix Figure 1 The present invention will be described in detail with specific embodiments.

[0026] like Figure 1As shown, this utility model provides a production system for methylene disulfonate, comprising an esterification reactor 1, an extraction tank 2, a primary centrifuge 3, a crystallization reactor 4, a secondary centrifuge 5, and a screw conveyor 6 connected in sequence. The outlet of the esterification reactor 1 is connected to the inlet of the extraction tank 2; the outlet of the extraction tank 2 is connected to the inlet of the primary centrifuge 3; the solid outlet of the primary centrifuge 3 is connected to the solid inlet of the crystallization reactor 4 via an elevator 7; the outlet of the crystallization reactor 4 is connected to the inlet of the secondary centrifuge 5; and the solid outlet of the secondary centrifuge 3 is connected to the inlet of the screw conveyor 6. The tops of the extraction tank 2 and the crystallization reactor 4 are both connected to a dichloromethane high-level tank 8, i.e., a dichloromethane high-level... The dichloromethane in tank 8 can be fed into extraction tank 2 and crystallization vessel 4 respectively. The top of extraction tank 2 is also connected to the upper end of the tube side of condenser 9 through a pipe, and the lower end of the tube side of condenser 9 is connected to the liquid inlet of esterification vessel 1 through a pipe. The dichloromethane entering extraction tank 2 is heated and vaporized, then condensed and refluxed into esterification vessel 1 through condenser 9, realizing the extraction of methylene disulfonate from the esterification liquid by dichloromethane and the reuse of dichloromethane. Since the material entering the primary centrifuge 3 and secondary centrifuge 5 contains both liquid and solid, a primary mother liquor tank 10 is connected to the liquid outlet of primary centrifuge 3; a secondary mother liquor tank 11 is connected to the liquid outlet of secondary centrifuge 5 to realize the collection of liquid.

[0027] The production system for methyl disulfonate of this application has a reasonable structure and uses dichloromethane instead of water to extract methyl disulfonate from the esterification liquid, which greatly reduces the amount of wastewater generated and does not generate intense heat during the treatment process, thus significantly reducing safety risks.

[0028] Specifically, the outlet of the esterification vessel 1 is connected to the inlet of the extraction tank 2 via a first pipe 12. An inverted U-shaped buffer section 121 is installed on the first pipe 12. The inverted U-shaped buffer section 121 utilizes solvent reflux and siphon principles to ensure continuous extraction of solid substances by pure solvent, saving solvent while maintaining a high extraction rate. By setting up the inverted U-shaped buffer section 121, the consumption of dichloromethane can be reduced, significantly decreasing the residue of acidic impurities, increasing product yield, and improving product quality, which aligns with the concept of environmentally friendly development.

[0029] Specifically, the inlet end of the buffer tube section 121 is connected to the outlet of the esterification vessel 1 via the first bent tube 122, and the outlet end of the buffer tube section 121 is connected to the inlet of the extraction tank 2 via the second bent tube 123. The first bent tube 122 and the second bent tube 123 further provide a buffering effect for the solvent, reducing the solvent flow rate and improving the extraction rate.

[0030] Specifically, the primary mother liquor tank 10 is connected to the top of the extraction tank 2 via a second pipe 13, and a first magnetic pump 14 is installed on the second pipe 13; the secondary mother liquor tank 11 is connected to the top of the crystallization vessel 4 via a third pipe 15, and a second magnetic pump 16 is installed on the third pipe 15. By setting the first magnetic pump 14 and the second magnetic pump 16, the solvent can be fully utilized, the generation of impurities can be reduced, and the extraction rate of the product can be increased.

[0031] Specifically, this application also includes a vacuum dryer 17, the inlet of which is connected to the outlet of the screw conveyor 6. The vacuum dryer 17 is used to dry methylene disulfonate.

[0032] Specifically, the esterification reactor 1 is equipped with a spiral stirrer 18. The spiral stirring method can improve the uniformity of solid-liquid phase mixing, thereby increasing the yield.

[0033] Specifically, the top of the extraction tank 2 is connected to the dichloromethane high-level tank 8 via the fourth pipe 19, and the fourth pipe 19 is equipped with a first valve 20; the top of the crystallization vessel 4 is connected to the dichloromethane high-level tank 8 via the fifth pipe 21, and the fifth pipe 21 is equipped with a second valve 22. By setting the first valve 20 and the second valve 22, the controllability of the dichloromethane flow rate can be increased.

[0034] Specifically, the crystallization vessel 4 is positioned diagonally above the centrifuge 3, and the elevator 7 is tilted at an angle of 15°-30°. The elevator 7 enables continuous conveying of solid materials, and by setting the elevator 7 at an inclined angle, production space can be saved on the one hand, and frictional resistance can be reduced on the other hand.

[0035] Specifically, a gas-liquid separator (not shown in the figure) is installed on the pipe between the lower end of the tube side of the condenser 9 and the liquid inlet of the esterification vessel 1. The liquid outlet of the gas-liquid separator is connected to the liquid inlet of the esterification vessel 1. The condensed dichloromethane liquid flows back to the esterification vessel 1. The gas outlet of the gas-liquid separator is connected to the tail gas treatment system. The non-condensable dichloromethane gas enters the tail gas treatment system with the induced draft fan.

[0036] Specifically, the dichloromethane high-level tank 8 is located above the crystallization vessel 4 and the extraction tank 2, allowing dichloromethane to quickly enter the crystallization vessel 4 and the extraction tank 2 under its own gravity.

[0037] The process for producing methylene disulfonate using the production system of this invention is as follows:

[0038] The raw materials for synthesizing methylene disulfonate, methylene disulfonic acid, paraformaldehyde, and phosphorus pentoxide, are added to esterification reactor 1 in a certain proportion and heated to 100℃~110℃ for esterification reaction. After the reaction is completed, when the esterification liquid cools to below 40℃, dichloromethane is added from dichloromethane high-level tank 8 to extraction tank 2. After the dichloromethane is heated to boiling, it is condensed and refluxed into esterification reactor 1 through condenser 9. After stirring and extraction, it flows into extraction tank 2 through first pipe 12. After extraction is completed, the liquid in extraction tank 2 cools to below 10℃ and is gravity-fed into primary centrifuge 3 for solid-liquid separation. The mother liquor is then added to the primary centrifuge. The mother liquor is placed in the mother liquor tank 10 and pumped back to the extraction tank 2 by the first magnetic pump 14 for reuse. The filter cake is lifted by the elevator 7 to the crystallization kettle 4 for recrystallization (dichloromethane is added to the crystallization kettle 4 from the dichloromethane high-level tank 8 before recrystallization). In the crystallization kettle 4, the solution is first heated to dissolve and then recrystallized at a low temperature. After crystallization, the liquid is fed into the secondary centrifuge 5 by gravity for centrifugation. The mother liquor after centrifugation is placed in the secondary mother liquor tank 11 and pumped back to the crystallization kettle 4 by the second magnetic pump 16 for reuse. The filter cake is transferred to the vacuum dryer 17 by the screw conveyor 6 for drying. Finally, qualified methylene disulfonate is obtained.

[0039] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific description herein should not be construed as limiting the substance and scope of the present invention. Various modifications made by those skilled in the art to the above embodiments after reading this specification are all within the scope of protection of the present invention.

Claims

1. A production system for methylene dimethyl sulfonate, characterized in that, It includes an esterification vessel, an extraction tank, a primary centrifuge, a crystallization vessel, a secondary centrifuge, and a screw conveyor connected in sequence, wherein: The top of the extraction tank and the top of the crystallization vessel are both connected to a dichloromethane high-level tank; the top of the extraction tank is also connected to the upper end of the tube side of the condenser via a pipe, and the lower end of the tube side of the condenser is connected to the liquid inlet of the esterification vessel via a pipe. The solid discharge port of the primary centrifuge is connected to the crystallization vessel via an elevator, and the liquid discharge port of the primary centrifuge is connected to the primary mother liquor tank; the solid discharge port of the secondary centrifuge is connected to the screw conveyor, and the liquid discharge port of the secondary centrifuge is connected to the secondary mother liquor tank.

2. The methyl disulfonate production system according to claim 1, characterized in that, The outlet of the esterification vessel is connected to the inlet of the extraction tank via a first pipe, and the first pipe is provided with an inverted U-shaped buffer section.

3. The methyl disulfonate production system according to claim 2, characterized in that, The inlet end of the buffer tube section is connected to the outlet of the esterification vessel via a first bent pipe, and the outlet end of the buffer tube section is connected to the inlet of the extraction tank via a second bent pipe.

4. The methyl disulfonate production system according to claim 1, characterized in that, The primary mother liquor tank is connected to the top of the extraction tank via a second pipe, and a first magnetic pump is installed on the second pipe; the secondary mother liquor tank is connected to the top of the crystallization vessel via a third pipe, and a second magnetic pump is installed on the third pipe.

5. The methyl disulfonate production system according to claim 1, characterized in that, It also includes a vacuum dryer, the inlet of which is connected to the outlet of the screw conveyor.

6. The methyl disulfonate production system according to claim 1, characterized in that, The esterification reactor is equipped with a spiral stirrer.

7. The methyl disulfonate production system according to claim 1, characterized in that, The top of the extraction tank is connected to the high-level dichloromethane tank via a fourth pipe, and a first valve is installed on the fourth pipe; the top of each crystallization vessel is connected to the high-level dichloromethane tank via a fifth pipe, and a second valve is installed on the fifth pipe.

8. The methyl disulfonate production system according to claim 1, characterized in that, The crystallization vessel is positioned diagonally above the primary centrifuge, and the elevator has an inclination angle of 15°-30°.

9. The methyl disulfonate production system according to claim 1, characterized in that, A gas-liquid separator is installed on the pipeline between the lower end of the tube side of the condenser and the liquid inlet of the esterification vessel. The liquid outlet of the gas-liquid separator is connected to the liquid inlet of the esterification vessel, and the gas outlet of the gas-liquid separator is connected to the exhaust gas treatment system.

10. The methyl disulfonate production system according to claim 1, characterized in that, The dichloromethane high-level tank is located above the crystallization vessel and the extraction tank.

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