TETD production system

Abstract

The utility model discloses a TETD production system, which comprises a reaction kettle and is characterized in that a stirring structure is arranged in the reaction kettle, a jacket is arranged outside the reaction kettle, and the stirring structure is arranged in the jacket. An n-butyl alcohol adding pipeline, a diethylamine adding pipeline, a hydrogen peroxide adding pipeline, a carbon disulfide adding pipeline and a carbon disulfide gas discharging pipeline are arranged at the top end of the reaction kettle, and the n-butyl alcohol adding pipeline is connected with an n-butyl alcohol storage tank through an n-butyl alcohol metering pump; according to the utility model, dropwise adding materials are added through the metering pumps, each metering pump is connected with each storage tank, automatic sealing feeding is realized, the harm to the body of a worker is reduced, carbon disulfide and n-butyl alcohol are recovered for next reaction after the reaction is finished, the loss of the materials is reduced, the production cost is reduced, and the production efficiency is improved. And meanwhile, the pollution problem in the subsequent treatment process is reduced.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, specifically a TETD production system. Background Technology

[0002] Vulcanization accelerators, often simply called accelerators, are used in rubber vulcanization to speed up the process, shorten vulcanization time, lower vulcanization temperature, and reduce the amount of vulcanizing agent required. They can also improve the physical and mechanical properties of the vulcanized rubber. Tetraethyl thiuram disulfide (TETD) is used as a super-accelerator and vulcanizing agent for natural rubber, styrene-butadiene rubber, nitrile rubber, butyl rubber, cis-butadiene rubber, and latex.

[0003] Currently, most tetraethylthiuram disulfide production processes employ a two-step method: condensation followed by oxidation. First, diethylamine, sodium hydroxide, and carbon disulfide are condensed at 30-40°C to produce sodium diethyldithiocarbamate. Then, the carbon residue is filtered, and the mother liquor is oxidized with chlorine or nitrous acid and air to produce tetraethylthiuram disulfide. After cooling, filtration, drying, and pulverization, the final product is obtained, with a yield of only 86%. While this production process is relatively mature, it suffers from significant waste, high product consumption quotas, high manual labor intensity, and a poor operating environment.

[0004] Regarding the TETD production process, we improved it by using ethanol (with recovered ethanol), water, diethylamine, and carbon disulfide for a condensation reaction, followed by direct oxidation with hydrogen peroxide after the reaction. However, the subsequent ethanol recovery requires distillation, which consumes relatively high energy. Therefore, we developed a production process using n-butanol as the reaction solvent, which is more conducive to the recovery of n-butanol solvent. Currently, the conventional operation involves manually adding diethylamine, n-butanol, and carbon disulfide to the reaction vessel. Carbon disulfide, for example, has a low boiling point (46.2℃) and an ignition temperature of 90℃. At room temperature and pressure, carbon disulfide is a colorless, transparent, slightly aromatic, fat-soluble liquid with extremely high volatility, flammability, and explosiveness. It also has an unpleasant rotten radish smell, posing a significant health hazard. Manual addition undoubtedly requires a large labor input, resulting in low production efficiency and is detrimental to environmental protection and safe production. Furthermore, a large amount of unreacted carbon disulfide, if directly fed into the post-processing steps, will lead to carbon disulfide pollution and waste. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a TETD production system that enables safe one-step production of tetraethylthiuram disulfide, improves production efficiency, and reduces energy consumption for solvent recovery.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A TETD production system, comprising a reaction vessel, characterized in that: a stirring structure is provided inside the reaction vessel; a jacket is provided outside the reaction vessel; the top of the reaction vessel is provided with a n-butanol inlet pipeline, a diethylamine inlet pipeline, a hydrogen peroxide inlet pipeline, a carbon disulfide inlet pipeline, and a carbon disulfide gas outlet pipeline; the n-butanol inlet pipeline is connected to a n-butanol storage tank via a n-butanol metering pump; the diethylamine inlet pipeline is connected to a diethylamine storage tank via a diethylamine metering pump; the hydrogen peroxide inlet pipeline is connected to a hydrogen peroxide storage tank via a hydrogen peroxide metering pump; and the carbon disulfide gas outlet pipeline is connected to the inlet of a condenser, wherein the condenser condenses... The liquid outlet pipeline is connected to the carbon disulfide receiving tank. The bottom outlet pipeline of the carbon disulfide receiving tank is connected to the carbon disulfide inlet pipeline. The carbon disulfide inlet pipeline is also connected to the carbon disulfide transfer pump. A carbon disulfide metering pump is installed on the carbon disulfide inlet pipeline. The bottom of the reactor 1 is equipped with a discharge pipeline connected to a centrifuge. The solid material from the centrifuge goes to the drying system. The top of the centrifuge is equipped with a wash water inlet pipeline. The bottom of the centrifuge is equipped with a centrifugal liquid discharge pipeline. The centrifugal liquid discharge pipeline is connected to a centrifugal liquid storage tank. The centrifugal liquid storage tank is connected to a separator. The organic phase outlet pipeline of the separator is connected to a n-butanol storage tank. The aqueous phase outlet pipeline of the separator is connected to a wastewater pool.

[0007] In the above scheme: the lower part of the jacket of the reactor is equipped with a general-purpose cooling brine inlet pipe, and the upper part is equipped with a general-purpose cooling brine outlet pipe. During the reaction process, the reactor is cooled by general-purpose cooling brine to ensure a suitable reaction temperature.

[0008] In the above scheme: a steam coil is installed inside the reactor, and the steam coil is staggered from the stirring structure. The stirring structure will not interfere with the steam coil. Steam is introduced into the steam coil to vaporize and discharge the carbon disulfide inside the reactor, which helps to improve the discharge efficiency of carbon disulfide.

[0009] In the above scheme: a detonation valve is installed at the top of the reactor. The detonation valve is connected to a waste gas treatment device for emergency detonation.

[0010] In the above scheme: a branch pipe is split from the condensate outlet pipeline of the condenser and connected to the reactor. In case of an abnormality, this branch pipe can be used to condense the non-condensable gases generated during the reaction process and return them to the reactor.

[0011] In the above scheme, a liquid-sealed water inlet pipeline is installed at the top of the carbon disulfide receiving tank. Since carbon disulfide has a higher density than water and is insoluble in water, the liquid seal can prevent the volatilization of carbon disulfide.

[0012] In the above scheme: the top of the carbon disulfide receiving tank is also equipped with an exhaust pipe that is connected to the workshop exhaust main pipe.

[0013] In the above scheme: the centrifuge's bottom centrifugal liquid discharge pipeline branches off into two branches; the centrifugal liquid storage tank is divided into a mother liquor storage tank and a washing liquid storage tank; one branch is connected to the mother liquor storage tank; the outlet pipeline of the mother liquor storage tank is connected to the separator; the other branch is connected to the washing liquid storage tank; the bottom of the washing liquid storage tank is provided with a washing liquid outlet pipeline; the washing liquid outlet pipeline also branches off into two branches; one branch is connected to the centrifuge's washing water inlet pipeline via a transfer pump; and the other branch is connected to the separator. This process separates the centrifuged mother liquor and the washing liquid. The mother liquor has a high n-butanol content and a low water content. After separation by a separatory tank, a small amount of water is removed, and the n-butanol returns to the n-butanol storage tank for reuse. The washing liquid enters the washing liquid storage tank. For the first water wash, water from the washing liquid storage tank can be used. For the second water wash, fresh water is added. After multiple reuses, the washing liquid enters the separatory tank again to separate the n-butanol and water. The aqueous phase from the separatory tank enters the wastewater pool for subsequent wastewater treatment, while the n-butanol is recycled.

[0014] A certain amount of n-butanol is added to the reactor using a n-butanol metering pump. Then, a specified amount of diethylamine is added using a metering pump. Stirring and cooling water are then activated. Next, a measured amount of carbon disulfide is added dropwise to the reactor using a carbon disulfide metering pump to initiate the condensation reaction. During the addition of carbon disulfide, brine is used for cooling to control the reaction temperature. After the carbon disulfide is added, the reaction proceeds for a certain period. After the condensation and heat preservation are completed, hydrogen peroxide is added dropwise to the reactor using a hydrogen peroxide metering pump to initiate the oxidation reaction. During the addition of hydrogen peroxide, brine is used for cooling. After the hydrogen peroxide is added, the reaction continues at this temperature. After the oxidation and heat preservation are completed, the material in the reactor is heated to 40-60°C. Unreacted carbon disulfide is discharged from the reactor and condensed in a condenser before being recycled to a carbon disulfide receiving tank for reuse in the next batch of condensation reaction. After the carbon disulfide is completely removed, the material in the reactor is cooled to 0-5℃. Then, the material in the reactor that has been cooled to the specified temperature is placed into a centrifuge for centrifugal dehydration to obtain the product.

[0015] After centrifugation, the centrifuged liquid is separated in a separatory tank to recover n-butanol, while the aqueous phase undergoes subsequent water treatment. This method allows for direct recovery of n-butanol without the need for distillation, thus reducing energy consumption.

[0016] This invention uses metering pumps to add materials dropwise. Each metering pump is connected to its own storage tank to achieve automatic sealed feeding, reducing harm to workers' health. After the reaction is complete, carbon disulfide and n-butanol are recovered for the next reaction, reducing material loss and pollution problems in subsequent processing. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the process flow of the reaction process of this utility model.

[0018] Figure 2 This is a schematic diagram of the centrifugation process. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] Example 1: As Figure 1 and 2 As shown, the TETD production system includes a reactor 1, with a stirring structure 2 inside the reactor 1 and a jacket outside the reactor 1. A general-purpose cold brine inlet pipe is located at the lower part of the jacket, and a general-purpose cold brine outlet pipe is located at the upper part. The general-purpose cold brine inlet pipe is connected to the brine circulation main pipe, and the general-purpose cold brine outlet pipe is connected to the general-purpose cold brine workshop return water main pipe.

[0021] The top of reactor 1 is equipped with n-butanol, diethylamine, hydrogen peroxide, and carbon disulfide inlet lines, as well as a carbon disulfide gas outlet line and a nitrogen line 101. Each of these lines is equipped with a feed valve, which is automatically controlled. The n-butanol inlet line is connected to the n-butanol storage tank 4 via a n-butanol metering pump 3.

[0022] The diethylamine inlet pipeline is connected to the diethylamine storage tank 6 via the diethylamine metering pump 5; the hydrogen peroxide inlet pipeline is connected to the hydrogen peroxide storage tank 8 via the hydrogen peroxide metering pump 7; the carbon disulfide gas outlet pipeline is connected to the inlet of the condenser 9; and the condensate outlet pipeline of the condenser 9 is connected to the carbon disulfide receiving tank 10. Figure 1 As shown, condenser 9 is an existing condenser, including a shell and a tube layer. Cooling water flows through the shell layer, and gas enters the tube layer from the top. The gas in the tube layer is condensed by the cooling water in the shell layer, becoming condensate, which exits from the bottom outlet pipe. A branch pipe from the condensate outlet pipe of condenser 9 connects to reactor 1. A liquid seal water inlet pipe 1001 is installed at the top of the carbon disulfide receiving tank 10. This liquid seal prevents the temporarily stored carbon disulfide from evaporating. An exhaust pipe 1002 is installed at the top of the carbon disulfide receiving tank 10, connecting to the workshop's main exhaust pipe.

[0023] The bottom outlet pipeline of the carbon disulfide receiving tank 10 is connected to the carbon disulfide inlet pipeline, which is also connected to the carbon disulfide transfer pump 13. The carbon disulfide transfer pump 13 is connected to the intermediate carbon disulfide storage device, which includes a storage tank. The upper part of the storage tank is equipped with a water seal, and the lower part is the carbon disulfide storage area. A nitrogen seal can also be installed in addition to the water seal (details omitted here). A carbon disulfide metering pump 14 is installed on the carbon disulfide inlet pipeline. The metering pump 14 meterly adds carbon disulfide to the reaction vessel.

[0024] A discharge pipeline 102 is installed at the bottom of the reactor 1. A steam coil 11 is installed inside the reactor 1, staggered from the stirring structure to avoid interference. A pressure relief valve is installed at the top of the reactor 1, connected to the workshop's main exhaust gas pipe. The discharge pipeline is connected to a centrifuge 12, from which solid materials exit the centrifuge 12 and are sent to a drying system. The centrifuge's top cover is equipped with a feed pipe 1201, a wash water inlet pipeline 1202, a nitrogen pipeline 1203, an exhaust pipe 1204, and a centrifugal liquid drain pipe 105. The structure of the centrifuge 1 itself is existing technology and will not be described in detail here. The wash water inlet pipeline 1202 is connected to a soft water storage tank 17, and a pump can be installed on the soft water inlet pipeline 1202. The feed pipe 1201 is connected to the reactor's discharge pipeline 102.

[0025] The centrifuge 12 is equipped with a centrifugal liquid discharge pipeline at its bottom, which is connected to a centrifugal liquid storage tank. The centrifugal liquid storage tank is connected to a separatory tank 16, which is existing technology. The organic phase outlet pipeline of the separatory tank 16 is connected to a n-butanol storage tank 4, and the aqueous phase outlet pipeline of the separatory tank 16 is connected to a wastewater pool. Figure 2 In this centrifuge, both the aqueous phase outlet pipeline and the organic phase outlet pipeline are located at the bottom. The aqueous phase is discharged first, followed by the organic phase n-butanol. Preferably, the centrifuge liquid discharge pipeline at the bottom of the centrifuge 12 branches into two branches. The centrifuge liquid storage tank is divided into a mother liquor storage tank 15 and a washing liquid storage tank 18. One branch is connected to the mother liquor storage tank 15, and the outlet pipeline of the mother liquor storage tank 15 is connected to the separator 16. The other branch is connected to the washing liquid storage tank 18. The bottom of the washing liquid storage tank 18 is equipped with a washing liquid outlet pipeline, which also branches into two branches. One branch is connected to the centrifuge's washing water inlet pipeline via a transfer pump, and the other branch is connected to the separator 16. Both the mother liquor storage tank and the washing liquid storage tank are equipped with exhaust gas pipes connected to the workshop's main exhaust gas pipe. In this invention, a pump can be appropriately installed on the transfer pipeline when power is required, or a high-level discharge method can be used.

[0026] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A TETD production system, comprising a reactor (1), characterized in that: The reactor (1) is equipped with a stirring structure (2), and the reactor (1) is equipped with a jacket. The top of the reactor (1) is equipped with a n-butanol inlet pipeline, a diethylamine inlet pipeline, a hydrogen peroxide inlet pipeline, a carbon disulfide inlet pipeline, and a carbon disulfide gas outlet pipeline. The n-butanol inlet pipeline is connected to the n-butanol storage tank (4) via a n-butanol metering pump (3). The diethylamine inlet pipeline is connected to the diethylamine storage tank (6) via a diethylamine metering pump (5). The hydrogen peroxide inlet pipeline is connected to the hydrogen peroxide storage tank (8) via a hydrogen peroxide metering pump (7). The carbon disulfide gas outlet pipeline is connected to the inlet of the condenser (9). The condensate outlet pipeline of the condenser (9) is connected to the carbon disulfide receiving tank (10). The bottom outlet pipeline of the reactor (1) is connected to the carbon disulfide inlet pipeline, which is also connected to the carbon disulfide transfer pump (13). A carbon disulfide metering pump (14) is installed on the carbon disulfide inlet pipeline. The bottom of the reactor (1) is provided with a discharge pipeline connected to the centrifuge (12). The solid material from the centrifuge (12) goes to the drying system. A washing water inlet pipeline is provided at the top of the centrifuge (12). A centrifugal liquid outlet pipeline is provided at the bottom of the centrifuge (12). The centrifugal liquid outlet pipeline is connected to the centrifugal liquid storage tank. The centrifugal liquid storage tank is connected to the separator (16). The organic phase outlet pipeline of the separator (16) is connected to the n-butanol storage tank (4). The aqueous phase outlet pipeline of the separator (16) is connected to the wastewater pool.

2. The TETD production system according to claim 1, characterized in that: The lower part of the jacket of the reactor (1) is provided with a general-purpose brine inlet pipe, and the upper part is provided with a general-purpose brine outlet pipe.

3. The TETD production system according to claim 2, characterized in that: The reactor (1) is equipped with a steam coil (11), which is offset from the stirring structure.

4. The TETD production system according to claim 3, characterized in that: The reactor (1) is equipped with a detonation valve at its top.

5. The TETD production system according to claim 4, characterized in that: A branch pipe from the condensate outlet line of the condenser (9) is connected to the reactor (1).

6. The TETD production system according to claim 5, characterized in that: The top of the carbon disulfide receiving tank (10) is provided with a liquid seal water inlet pipeline (1001).

7. The TETD production system according to claim 6, characterized in that: The top of the carbon disulfide receiving tank (10) is also equipped with an exhaust pipe that is connected to the workshop exhaust main pipe.

8. The TETD production system according to claim 7, characterized in that: The centrifuge (12) has two branch pipes branching off from the centrifugal liquid discharge pipeline at the bottom. The centrifugal liquid storage tank is divided into a mother liquor storage tank (15) and a washing liquid storage tank (18). One branch pipe is connected to the mother liquor storage tank (15). The outlet pipeline of the mother liquor storage tank (15) is connected to the separator (16). The other branch pipe is connected to the washing liquid storage tank (18). The washing liquid storage tank (18) has a washing liquid outlet pipeline at the bottom. The washing liquid outlet pipeline also branches off from two branch pipes. One branch pipe is connected to the centrifuge's washing water inlet pipeline through a transfer pump. The other branch pipe is connected to the separator (16).

Images