CN111087280A - Production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination - Google Patents
Production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination Download PDFInfo
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Abstract
The invention relates to a production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination. Comprises chlorination process, hydrogen chloride removing process, separation process and residual liquid recovery process. The method has high selectivity of two steps of reaction, and the selectivity of both acetylene chlorination and dehydrochlorination is more than 95 percent; more than 98 percent of dichlorohydrocarbon generated by chlorination is converted into trichloroethylene and a small amount of tetrachloroethylene through dehydrochlorination reaction and a perfect separation process; realizes the control of the whole production process, prevents and reduces the generation of three wastes: high boiling generated by the trichloroethylene device is sent back to the device for circular reaction, and low boiling point substances and waste generated by equipment maintenance are sent to a recovery device for further treatment and then sent back to the trichloroethylene device; a small amount of waste gas generated by the device is evacuated at a high point under the protection of nitrogen; the wastewater generated by the device is sent to a park for uniform treatment; the consumption quota of chlorine and acetylene is about 10 percent lower than the average domestic level.
Description
Technical Field
The invention relates to a production method for preparing trichloroethylene, in particular to a production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination.
Background
Trichloroethylene (TCE) is an important chemical raw material, is a solvent with extremely strong dissolving capacity, and is industrially used for metal cleaning, degreasing, fiber degreasing and cleaning of electronic elements; trichloroethylene is used as a raw material intermediate and can be used for producing tetrachloroethylene, chloroacetic acid, dichloroacetyl chloride, octachlorodipropyl ether, HCFC-124, HFC-125, HFC-134 a and the like; also used as an extractant, a solvent and a low-temperature heat transfer oil medium; with the rapid development of the electronic industry and the metal processing industry in recent years, the demand of trichloroethylene as the high-quality performance of the cleaning agent is continuously increased; in addition, trichloroethylene is used as an important raw material of the green refrigerant HFC-134 a, and the quality of the trichloroethylene changes along with the development of the production technology of HFC-134 a and HFC-125 in China and the popularization of the market range.
The TCE production mainly comprises a petroleum ethylene route and a calcium carbide acetylene route, and the calcium carbide method is divided into a saponification method and a gas phase catalysis method according to an HCl removal process; compared with saponification methods, the gas-phase catalytic dehydrochlorination process newly developed in recent years has the advantages of small amount of waste water, low material energy consumption and the like; the domestic saponification method is a gradually eliminated process, and the gas-phase catalytic HCl removal process production is a process technology which is active in national industrial policy advocate; the technical scheme adopted by the project is a novel process route integrating the advantages of the processes, namely calcium carbide acetylene chlorination and gas phase catalytic dehydroHCL method for producing trichloroethylene; accords with the characteristics of national conditions of China, and belongs to a novel project encouraging the development of China.
Disclosure of Invention
The invention aims to solve the problems, and provides a production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination.
The invention solves the problems and adopts the technical scheme that:
a production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination comprises a chlorination process, a hydrogen chloride removal process, a separation process and a residual liquid recovery process, and is carried out according to the following steps:
a chlorination process:
(1) acetylene from acetylene drying and chlorine from chlorine drying enter a tower from the bottom of a chlorination tower, gaseous tetrachloroethane continuously produced from the top of the tower is condensed by a chlorination complete condenser, and then returns to the tower through a dehydrator to maintain the liquid level in the tower, and the rest part enters a crude tetrachloroethane tank through a liquid seal cylinder;
(II) hydrogen chloride removal step:
(2) pumping crude tetrachloroethane in a crude tetrachloroethane tank into a heat exchanger through a pump to exchange heat with high-temperature reaction gas from a dehydrochlorination reactor, then entering a tetrachloroethane rectifying tower from the middle part of the tower, condensing rising steam in the tower through a full condenser, then entering a reflux tank, refluxing most of condensate through the reflux pump and an adjusting valve, extracting a small amount of condensate, allowing 1.1.2-trichloroethane extracted from the top of the tower to enter a top liquid tank, condensing uncondensed gas at the top of the tower through a tail gas cooler, then evacuating under the protection of nitrogen, and injecting 1.1.2.2-tetrachloroethane into a kettle liquid tank through a pump;
(3) the tetrachloroethane in the kettle liquid tank enters a gasifier for gasification, the gasified tetrachloroethane gas is sent to a preheater for heat exchange with high-temperature heat conducting oil from a heat conducting oil furnace, the gas enters a dehydrochlorination reactor after being heated to a required reaction temperature, and the tetrachloroethane gas is subjected to dehydrochlorination reaction in a fixed bed reactor under the action of a catalyst;
(III) a separation step:
(4) the reaction gas mixture from the heat conducting oil heat exchanger enters an analytical tower, condensable gas in rising steam is completely condensed by a full condenser and a tail cooler and then flows back to the tower, a small amount of chlorohydrocarbon is still carried in uncondensed hydrogen chloride gas, the hydrogen chloride gas is cooled by a hydrogen chloride cooler by using chilled brine, after chlorohydrocarbons such as TCE and the like are removed by a high-efficiency fiber catcher, the hydrogen chloride is boosted by a booster and then is made into 25-30% hydrochloric acid in a two-stage falling film absorption mode, and the hydrochloric acid is sold as a byproduct;
(5) the solution in the desorption tower flows into a kettle tank, and is sent to a low-boiling tower after being metered, and low-boiling substances are distilled out from the top of the tower. Continuously feeding the low-boiling tower bottom liquid into a trichloroethylene tower by using a trichloroethylene feeding pump, controlling the reflux ratio to ensure that the content of the trichloroethylene at the tower top is more than 99.99 percent, and conveying the extracted trichloroethylene to a finished product storage, transportation and packaging process;
(6) the trichloroethylene tower bottom liquid contains tri-chloroethylene, tetrachloroethylene and tetrachloroethane, when the liquid level of the tower bottom liquid tank reaches above 2/3, the middle distillate tower and the tetrachloroethylene tower are started, and tetrachloroethylene is extracted from the top of the tetrachloroethylene tower and sent to the packaging process;
(IV) a residual liquid recovery process:
(7) and (3) sending the liquid collected in the chlorination residue tank to a residual liquid recovery tower, recovering and extracting tetrachloroethane, sending the tetrachloroethane to a crude tetrachloroethane tank, and sending the kettle liquid to a high-boiling-point substance storage tank for sale.
Compared with the prior art, the invention adopting the technical scheme has the outstanding characteristics that:
① the selectivity of the two steps is high, and the selectivity of the acetylene chlorination and dehydrochlorination is more than 95 percent.
② the dichlorohydrocarbons generated by chlorination are converted into trichloroethylene and a small amount of tetrachloroethylene by more than 98% through dehydrochlorination and a perfect separation process.
③ realizes the control of the whole production process, prevents and reduces the generation of three wastes, the high boiling generated by the trichloroethylene device is sent back to the device for circular reaction, the low boiling point substances and the waste materials generated by the equipment maintenance are sent to the recovery device for further treatment and then sent back to the trichloroethylene device, a small amount of waste gas generated by the device is evacuated at high points under the protection of nitrogen, and the waste water generated by the device is sent to a park for unified treatment.
④ the consumption quota of chlorine and acetylene is about 10 percent lower than the average domestic level.
Preferably, the further technical scheme of the invention is as follows:
in the step (1), the molecular ratio of chlorine to acetylene in the acetylene chlorination reaction is 2: 1.01, acetylene is in slight excess, the reaction is carried out under negative pressure, the acetylene chlorination tower is a jacketed reaction tower made of carbon steel, tetrachloroethane and ferric chloride are filled in the tower, steam and cooling water are led in the jacket, an explosion-proof membrane is arranged at the top of the tower, and a liquid level meter is arranged in the tower.
In the step (1), a chlorination water injection pump in the chlorination process is mainly used for vacuumizing to ensure that a chlorination reactor keeps negative pressure, so tail water contains a small amount of acetylene which is excessive in reaction, the tail water is firstly sent to a spray degassing tower, the acetylene is removed by blowing compressed air, and the tail water is kept alkaline to neutralize hydrogen chloride, chloroacetic acid and chlorine in the tail gas and is sent to a sewage treatment plant in a centralized manner.
In the step (3), the heat conduction oil is designed to adopt an electric heating furnace and is arranged near the main device, so that the heat loss caused by overlong heat conduction oil pipelines is avoided.
In the step (3), the dehydrochlorination reactor is a fixed bed tubular reactor, the inside of the tube is filled with the catalyst, heat conducting oil is filled between the tubes, and the dehydrochlorination reactor is made of 0Cr18Ni9Ti stainless steel so as to ensure the reliability of the production process.
In the step (5), the noncondensable tail gas at the top of the trichloroethylene rectifying tower contains trace hydrogen chloride gas and carries a small amount of tetrachloroethane and trichloroethylene steam, the concentration of the carried chlorohydrocarbon steam is mainly reduced by a freezing mode, and a tail gas cooler is arranged after a full condenser and can condense most of chlorohydrocarbon, so that the content of chlorohydrocarbon in the tail gas reaches the national emission standard.
In the step (6), trichloroethylene containing a small amount of tetrachloroethylene is extracted from the top of the middle distillate tower and returned to the solution tank of the resolution kettle; the unreacted tetrachloroethane is extracted from the tetrachloroethylene tower kettle and recycled to the tetrachloroethane tank.
A small amount of waste gas generated in the trichloroethylene separation process is subjected to high-point emptying under the protection of nitrogen, and the waste gas generated in the trichloroethylene chlorination process is subjected to high-point emptying after air purging, degassing and dilution by adopting a degassing tower and a fan device.
The intermediate material tank and the finished product tank are protected by nitrogen during normal production to prevent the products from oxidative decomposition, and when the device is started and stopped, the replacement of the tower and the container adopts nitrogen replacement to save energy.
Drawings
FIG. 1 is a schematic diagram of a process flow of an embodiment of the present invention.
The specific implementation mode is as follows:
the invention will be further illustrated by the following examples, which are intended only for a better understanding of the present invention and therefore do not limit the scope of the invention.
Referring to fig. 1, a method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination, wherein the whole production process is controlled by DCS. According to the production process requirement and the device scale, a set of emergency shutdown system (ESD) is arranged to realize emergency shutdown and safety interlocking protection of the device.
The method comprises the following steps:
a. acetylene from acetylene drying and chlorine from chlorine drying are metered by a pore plate flowmeter and enter a tower from the bottom of a chlorination tower, and the molecular ratio of the chlorine to the acetylene is 2: 1.01, slight acetylene excess. Tetrachloroethane is filled in the tower, ferric trichloride is suspended in the tetrachloroethane, the reaction is carried out under negative pressure, the vacuum degree of the system is 50 KPa-80 KPa, and the reaction temperature is 100-130 ℃; after the gaseous tetrachloroethane continuously produced at the tower top is condensed by a chlorination complete condenser, the gaseous tetrachloroethane returns to the tower through a dehydrator part, the liquid level in the tower is maintained, and the rest part enters a crude tetrachloroethane tank through a liquid seal cylinder.
b. Pumping the crude tetrachloroethane in the crude tetrachloroethane tank into a heat exchanger by a pump, carrying out heat exchange with high-temperature reaction gas from a HCL removal reactor, and then entering a tetrachloroethane rectifying tower from the middle part of the tower; the temperature of the top of the tower is controlled to be 90-110 ℃, and the temperature of the bottom of the tower is controlled to be 145-157 ℃. Condensing ascending steam in the tower through a full condenser and then entering a reflux tank, wherein condensate mostly reflows through a reflux pump and an adjusting valve, and the reflux ratio is controlled to be 30-40; small amount is extracted, the extraction amount at the top of the tower is 1 to 3 percent of the extraction amount at the bottom of the tower in general, and the extraction (1.1.2-trichloroethane) at the top of the tower enters a top liquid tank; the uncondensed gas at the tower top is condensed by a tail gas cooler and then is evacuated under the protection of nitrogen, and the tower bottom liquid (1.1.2.2-tetrachloroethane) is injected into a kettle liquid tank by a pump, wherein the content of 1.1.2-trichloroethane in the tower bottom liquid is less than or equal to 0.01 percent.
c. The tetrachloroethane in the kettle liquid tank enters a gasifier to be gasified, the gasifier is heated by steam, the gasified tetrachloroethane gas is sent to a preheater to exchange heat with high-temperature heat conduction oil from a heat conduction oil furnace, and the tetrachloroethane gas enters a HCL removal reactor after being heated to the required reaction temperature; the pressure difference between the inlet and the outlet of the reactor is less than or equal to 50KPa, the tetrachloroethane gas is subjected to a dehydroHCl reaction in a fixed bed reactor under the action of a catalyst, the initial reaction temperature is about 200 ℃, and the reaction temperature is gradually increased to 285-290 along with the reduction of the activity of the catalyst to generate trichloroethylene.
d. The reaction gas mixture from the heat transfer oil heat exchanger enters an analytical tower, the temperature at the top of the tower is controlled to be 83-95 ℃, the temperature at the bottom of the tower is controlled to be 95-105 ℃, the pressure at the top of the tower is +/-5 KPa, and the pressure at the bottom of the tower is 50 KPa; after the condensable gas in the rising steam is completely condensed by a full condenser and a tail gas cooler, a small amount of chlorohydrocarbon is still carried in the uncondensed HCl gas in a reflux tower, the HCl gas is cooled by a HCl cooler by using frozen brine, after chlorohydrocarbons such as TCE (trichloroacetic acid) and the like are removed by a high-efficiency fiber catcher, hydrogen chloride is boosted by a booster, and then one path of hydrogen chloride is made into 25-30% hydrochloric acid in a two-stage falling film absorption mode, and the hydrochloric acid is sold as a byproduct;
e. the solution in the desorption tower flows into a solution tank in the desorption tower, the acidity of the solution in the desorption tower is less than or equal to 30PPm, the solution is delivered to a low-boiling tower after being metered, and low-boiling substances are distilled from the top of the tower; the tower top temperature of the low-boiling tower is 65-90 ℃, the tower bottom temperature is 80-100 ℃, the kettle liquid of the low-boiling tower is continuously fed into a trichloroethylene tower by a trichloroethylene feeding pump, the reflux ratio is controlled to ensure that the content of the trichloroethylene at the tower top is more than 99.99 percent, and the produced trichloroethylene is fed into a finished product storage, transportation and packaging process; the temperature of the trichloroethylene is less than or equal to 40 ℃ after the trichloroethylene is extracted and cooled; the trichloroethylene tower should reduce the trichloroethylene content in the kettle liquid as much as possible under the premise of ensuring that the purity of the trichloroethylene at the tower top is more than 99.99 percent, and is preferably below 2 percent; when the content of the trichloroethylene in the kettle liquid is higher, the heating steam pressure set value of the trichloroethylene reboiler is required to be increased slowly in time.
f. The trichloroethylene tower bottoms contain trichloroethylene, tetrachloroethylene and tetrachloroethane; when the liquid level of the kettle liquid tank reaches above 2/3, starting the middle distillate tower and the tetrachloroethylene tower, extracting trichloroethylene containing a small amount of tetrachloroethylene from the top of the middle distillate tower, and returning the trichloroethylene to the analysis kettle liquid tank; the tetrachloroethylene is extracted from the top of the tetrachloroethylene tower and sent to a packaging process, and the unreacted tetrachloroethane is extracted from the bottom of the tetrachloroethylene tower and recycled to the tetrachloroethane tank; the temperature at the top of the tetrachloroethylene tower is controlled to be 115-125 ℃, the temperature at the bottom of the tetrachloroethylene tower is controlled to be 150-160 ℃, the pressure at the top of the tetrachloroethylene tower is less than 20KPa, and the pressure at the bottom of the tetrachloroethylene tower is less than or equal to 100 KPa.
g. The liquid collected in the chlorination residue tank is sent to a residue recovery device, which consists of a distillation still with a stirrer and an intermittent rectification tower, wherein the tower can be used for normal pressure distillation, reduced pressure distillation and neutralization treatment; the recovered tetrachloroethane is sent to a crude tetrachloroethane tank, and the kettle liquid is sent to a high-boiling-point substance storage tank for sale.
The method has high selectivity of two steps of reaction, and the selectivity of both acetylene chlorination and dehydrochlorination is more than 95 percent; more than 98 percent of dichlorohydrocarbon generated by chlorination is converted into trichloroethylene and a small amount of tetrachloroethylene through dehydrochlorination reaction and a perfect separation process; realizes the control of the whole production process, and prevents and reduces the generation of three wastes. High boiling generated by the trichloroethylene device is sent back to the device for circular reaction, and low boiling point substances and waste generated by equipment maintenance are sent to a recovery device for further treatment and then sent back to the trichloroethylene device. A small amount of waste gas generated by the device is exhausted at a high point under the protection of nitrogen. The wastewater generated by the device is sent to a park for uniform treatment; the consumption quota of chlorine and acetylene is about 10 percent lower than the average domestic level.
In conclusion, the production process is safe and reliable, the discharge amount of three wastes is greatly reduced, and compared with the trichloroethylene production technology of the traditional calcium carbide acetylene chlorination-saponification process, the production process has stronger advantages in the aspects of product quality, consumption reduction, energy conservation, environmental protection and the like.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, which is defined in the appended claims.
Claims (9)
1. A production method for preparing trichloroethylene by acetylene chlorination-gas phase catalytic dehydrochlorination comprises a chlorination process, a hydrogen chloride removal process, a separation process and a residual liquid recovery process, and is characterized by comprising the following steps:
a chlorination process:
(1) acetylene from acetylene drying and chlorine from chlorine drying enter a tower from the bottom of a chlorination tower, gaseous tetrachloroethane continuously produced from the top of the tower is condensed by a chlorination complete condenser, and then returns to the tower through a dehydrator to maintain the liquid level in the tower, and the rest part enters a crude tetrachloroethane tank through a liquid seal cylinder;
(II) hydrogen chloride removal step:
(2) pumping crude tetrachloroethane in a crude tetrachloroethane tank into a heat exchanger through a pump to exchange heat with high-temperature reaction gas from a dehydrochlorination reactor, then entering a tetrachloroethane rectifying tower from the middle part of the tower, condensing rising steam in the tower through a full condenser, then entering a reflux tank, refluxing most of condensate through the reflux pump and an adjusting valve, extracting a small amount of condensate, allowing 1.1.2-trichloroethane extracted from the top of the tower to enter a top liquid tank, condensing uncondensed gas at the top of the tower through a tail gas cooler, then evacuating under the protection of nitrogen, and injecting 1.1.2.2-tetrachloroethane into a kettle liquid tank through a pump;
(3) the tetrachloroethane in the kettle liquid tank enters a gasifier for gasification, the gasified tetrachloroethane gas is sent to a preheater for heat exchange with high-temperature heat conducting oil from a heat conducting oil furnace, the gas enters a dehydrochlorination reactor after being heated to a required reaction temperature, and the tetrachloroethane gas is subjected to dehydrochlorination reaction in a fixed bed reactor under the action of a catalyst;
(III) a separation step:
(4) the reaction gas mixture from the heat conducting oil heat exchanger enters an analytical tower, condensable gas in rising steam is completely condensed by a full condenser and a tail cooler and then flows back to the tower, a small amount of chlorohydrocarbon is still carried in uncondensed hydrogen chloride gas, the hydrogen chloride gas is cooled by a hydrogen chloride cooler by using chilled brine, after chlorohydrocarbons such as TCE and the like are removed by a high-efficiency fiber catcher, the hydrogen chloride is boosted by a booster and then is made into 25-30% hydrochloric acid in a two-stage falling film absorption mode, and the hydrochloric acid is sold as a byproduct;
(5) the bottom liquid of the desorption tower flows into a kettle liquid tank, and is sent to a low-boiling tower after being metered, low-boiling substances are distilled from the top of the tower, the bottom liquid of the low-boiling tower is continuously sent to a trichloroethylene tower by a trichloroethylene charging pump, the reflux ratio is controlled to ensure that the content of the trichloroethylene at the top of the tower is more than 99.99 percent, and the extracted trichloroethylene is sent to a finished product storage, transportation and packaging process;
(6) the trichloroethylene tower bottom liquid contains tri-chloroethylene, tetrachloroethylene and tetrachloroethane, when the liquid level of the tower bottom liquid tank reaches above 2/3, the middle distillate tower and the tetrachloroethylene tower are started, and tetrachloroethylene is extracted from the top of the tetrachloroethylene tower and sent to the packaging process;
(IV) a residual liquid recovery process:
(7) and (3) sending the liquid collected in the chlorination residue tank to a residual liquid recovery tower, recovering and extracting tetrachloroethane, sending the tetrachloroethane to a crude tetrachloroethane tank, and sending the kettle liquid to a high-boiling-point substance storage tank for sale.
2. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (1), the molecular ratio of chlorine to acetylene in the acetylene chlorination reaction is 2: 1.01, acetylene is in slight excess, the reaction is carried out under negative pressure, the acetylene chlorination tower is a jacketed reaction tower made of carbon steel, tetrachloroethane and ferric chloride are filled in the tower, steam and cooling water are led in the jacket, an explosion-proof membrane is arranged at the top of the tower, and a liquid level meter is arranged in the tower.
3. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (1), a chlorination water injection pump in the chlorination process is mainly used for vacuumizing to ensure that a chlorination reactor keeps negative pressure, so tail water contains a small amount of acetylene which is excessive in reaction, the tail water is firstly sent to a spray degassing tower, the acetylene is removed by blowing compressed air, and the tail water is kept alkaline to neutralize hydrogen chloride, chloroacetic acid and chlorine in the tail gas and is sent to a sewage treatment plant in a centralized manner.
4. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (3), the heat conduction oil is designed to adopt an electric heating furnace and is arranged near the main device, so that the heat loss caused by overlong heat conduction oil pipelines is avoided.
5. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (3), the dehydrochlorination reactor is a fixed bed tubular reactor, the inside of the tube is filled with the catalyst, heat conducting oil is filled between the tubes, and the dehydrochlorination reactor is made of 0Cr18Ni9Ti stainless steel so as to ensure the reliability of the production process.
6. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (5), the noncondensable tail gas at the top of the trichloroethylene rectifying tower contains trace hydrogen chloride gas and carries a small amount of tetrachloroethane and trichloroethylene steam, the concentration of the carried chlorohydrocarbon steam is mainly reduced by a freezing mode, and a tail gas cooler is arranged after a full condenser and can condense most of chlorohydrocarbon, so that the content of chlorohydrocarbon in the tail gas reaches the national emission standard.
7. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: in the step (6), trichloroethylene containing a small amount of tetrachloroethylene is extracted from the top of the middle distillate tower and returned to the solution tank of the resolution kettle; the unreacted tetrachloroethane is extracted from the tetrachloroethylene tower kettle and recycled to the tetrachloroethane tank.
8. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: a small amount of waste gas generated in the trichloroethylene separation process is subjected to high-point emptying under the protection of nitrogen, and the waste gas generated in the trichloroethylene chlorination process is subjected to high-point emptying after air purging, degassing and dilution by adopting a degassing tower and a fan device.
9. The process for the production of trichloroethylene by the chlorination-gas phase catalytic dehydrochlorination of acetylene according to claim 1, characterized in that: the intermediate material tank and the finished product tank are protected by nitrogen during normal production to prevent the products from oxidative decomposition, and when the device is started and stopped, the replacement of the tower and the container adopts nitrogen replacement to save energy.
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| CN114685238A (en) * | 2020-12-25 | 2022-07-01 | 蓝星（北京）技术中心有限公司 | Process and device for continuously producing chloroprene |
| CN117776860A (en) * | 2024-02-28 | 2024-03-29 | 山东新龙科技股份有限公司 | Method and device for co-producing trichloroethylene and tetrachloroethylene |
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| CN102267868A (en) * | 2010-06-01 | 2011-12-07 | 滨化集团股份有限公司 | Industrial production apparatus for trichloroethylene |
| CN102775269A (en) * | 2012-07-13 | 2012-11-14 | 中国石油集团东北炼化工程有限公司葫芦岛设计院 | Trichloroethylene gas phase catalysis production method |
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| CN201762266U (en) * | 2010-06-01 | 2011-03-16 | 滨化集团股份有限公司 | Trichloroethylene industrialized production device |
| CN102267868A (en) * | 2010-06-01 | 2011-12-07 | 滨化集团股份有限公司 | Industrial production apparatus for trichloroethylene |
| CN102775269A (en) * | 2012-07-13 | 2012-11-14 | 中国石油集团东北炼化工程有限公司葫芦岛设计院 | Trichloroethylene gas phase catalysis production method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114685238A (en) * | 2020-12-25 | 2022-07-01 | 蓝星（北京）技术中心有限公司 | Process and device for continuously producing chloroprene |
| CN117776860A (en) * | 2024-02-28 | 2024-03-29 | 山东新龙科技股份有限公司 | Method and device for co-producing trichloroethylene and tetrachloroethylene |
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| CN111087280B (en) | 2023-08-29 |
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