CN112430195A - Device and process for producing DMAC (dimethylacetamide) under catalyst-free and low-pressure conditions - Google Patents
Device and process for producing DMAC (dimethylacetamide) under catalyst-free and low-pressure conditions Download PDFInfo
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Abstract
The invention belongs to the technical field of DMAC (dimethylacetamide) production, and particularly discloses a device and a process for producing DMAC under the conditions of no catalyst and low pressure, which comprise a DMAC batching synthesis system and a rectification system, wherein the DMAC batching synthesis system comprises a raw material batching system and a reaction system communicated with the batching system, the rectification system comprises a rectification first tower system communicated with the reaction system, a rectification second tower system communicated with the rectification first tower system, a rectification third tower system communicated with the rectification second tower system and a DMAC product output from the rectification third tower system, the reaction system comprises a reactor, the lower part of the reactor is provided with a preheating and heating system, the upper part of the reactor is provided with a condensation liquefaction recycling system, the process mainly introduces a refining rectification process into the DMAC system, the product purity is improved to 99.99% in the DMAC production process, the acid content is less than 10ppm, and the annual output reaches 3 ten thousand tons.
Description
Technical Field
The invention belongs to the technical field of DMAC (dimethylacetamide) production, and particularly relates to a device and a process for producing DMAC under the conditions of no catalyst and low pressure.
Background
Due to the limitation of production process and equipment, the production scale of DMAC (dimethyl acetamide) by using glacial acetic acid and dimethylamine as raw materials under the conditions of no catalyst and low pressure is small, the productivity is low, after the first 6000 t/a production line of 9, 11 and 11 days in 2004, the second 6000 t/a production line of 11, 12 days in 2005 is also smoothly put into operation, the production line is the first ten thousand ton grade DMAC production line in China, the DuPont production technology is introduced into Jiangshan of Zhejiang, and the 2 ten thousand t/a production line is built by using acetic acid as the raw material. Aiming at the industrial problems of low DMAC (dimethylacetamide) productivity and poor quality, a set of efficient production-improving and quality-improving production process is developed and tried out, so that the product purity can be improved to 99.99%, the acid content is less than 10ppm, and the annual output reaches 3 ten thousand tons.
Disclosure of Invention
The invention aims to provide a device and a process for producing DMAC under the conditions of no catalyst and low pressure.
In order to achieve the purpose, the invention adopts the technical scheme that:
the utility model provides a device of production DMAC under catalyst-free, low pressure condition, includes DMAC batching synthetic system and rectification system, DMAC batching synthetic system include raw materials feed proportioning system and with the reaction system of feed proportioning system UNICOM, the rectification system includes the rectification tower system with reaction system intercommunication, with the rectification tower system of rectification tower system UNICOM, and from the DMAC product of rectification tower system output, reaction system includes the reactor, and the reactor lower part is equipped with preheating system, and reactor upper portion is equipped with condensation liquefaction cyclic utilization system.
Further, a rectification tower system includes the dehydrogenation tower, a tower reboiler that is linked together with the dehydrogenation tower lower part, the dehydrogenation tower top still is equipped with a tower heat exchanger, a tower heat exchanger links to each other with a tower condenser on the dehydrogenation tower top, a tower condenser export links to each other with a tower reflux groove import, a tower reflux groove export links to each other with a tower reflux pump import, a tower reflux pump export is connected with the dehydrogenation tower top, the unnecessary material of a tower reflux groove is through a tower reflux pump sending to methylamine production unit and is recycled.
Further, the rectification two-tower system comprises a product tower and a two-tower reboiler communicated with the product tower, a two-tower heat exchanger is arranged at an outlet of the product tower, a two-tower condenser is arranged at an outlet of the two-tower heat exchanger, a two-tower reflux groove is arranged at an outlet of the two-tower condenser, materials are conveyed to the top of the product tower through a two-tower reflux pump at an outlet of the two-tower reflux groove, redundant materials in the two-tower reflux groove are conveyed to a rectification three-tower system, a two-tower kettle cooler is further arranged at the bottom of the product tower, the two-tower kettle cooler conveys the materials to a batching system through a two-tower tail liquid pump, redundant tail liquid in the two-tower kettle cooler is discharged to a heavy component tank, a two-tower vacuum tank is further arranged at the rectification two-tower system, an inlet of the two-tower vacuum tank is communicated with the two-tower condenser and the two-tower.
Further, the rectification three-tower system comprises a purification tower and a three-tower reboiler connected with the purification tower, wherein a three-tower condenser I is arranged at an outlet of the purification tower, the three-tower condenser I is communicated with a three-tower condenser II, an outlet of the three-tower condenser I is connected with a three-tower reflux tank I, and the three-tower reflux tank I is connected with the top of the purification tower through a three-tower reflux pump I; the outlet of the third tower condenser II is connected with a third tower reflux groove II, the third tower reflux groove II is connected with the inlet of the dehydrogenation tower through a third tower reflux pump II, the purifying tower is also provided with a lateral system which comprises a measuring line outlet arranged at one side of the top of the purifying tower and a measuring line condenser connected with the measuring line outlet, the outlet of the measuring line condenser is connected with a measuring line reflux groove, the measuring line reflux groove is communicated with a measuring line inlet arranged at the top of the purifying tower through a measuring line pump, the redundant DMAC finished product of the measuring line reflux groove is output to a middle tank, the rectification three-tower system is also provided with a three-tower vacuum tank, the inlet of the three-tower vacuum tank is communicated with a three-tower condenser I, a three-tower condenser II, a three-tower reflux groove I and a three-tower reflux groove II, the outlet of the three-tower vacuum tank is subjected to water seal removal through a three-tower vacuum pump, the bottom of the purifying tower is provided with a three-tower kettle cooler which is connected with the product tower through a three-tower tail liquid pump.
Further, the two-tower vacuum pump and the three-tower vacuum pump are both gas delivery pumps, and the pressure of each gas delivery pump is 0-100 Kpa.
A process for the production of a device for the production of DMAC under catalyst-free, low-pressure conditions, comprising the steps of:
(1) compounding ingredients: respectively pumping acetic acid and DMA from a batching system to a DMAC reaction system to react for 8 hours at 220 ℃ and 3.2MPa, condensing unreacted materials from the top of the reactor through a condensation liquefaction circulating system, returning the materials from the bottom of the reactor to participate in the reaction again, and feeding the crude products from the reactor into a rectification first-tower system by virtue of pressure difference;
(2) and (3) preparing a finished product by rectification and purification: the crude product from the reactor enters a dehydrogenation tower, light components in the dehydrogenation tower flow out from the tower top to a tower condenser to be condensed, distillate flows back to the dehydrogenation tower through a tower reflux groove and a tower reflux pump to regulate the temperature of the upper middle part of the dehydrogenation tower, when the liquid level of the tower reflux groove is more than 10%, redundant materials in the tower reflux groove are sent to a methylamine production unit through the tower reflux pump to be reused, the mixture at the bottom of the dehydrogenation tower is sent to a product tower through pressure difference, light components DMAC in the product tower are condensed into a second tower reflux groove through a tower top and a second tower condenser, part of materials in the second tower reflux groove are sent to the product tower through a second tower reflux pump to be refluxed, the other part of materials are extracted to a purification tower, the materials in the tower bottom cooler of the second tower are sent to a batching system through a second tower tail liquid pump and then enter the reactor to continue to react, and redundant tail liquid in the tower bottom cooler of the second tower is; light component DMAC in the purification tower is condensed by a tower top three-tower condenser I and a three-tower condenser II and respectively enters a three-tower reflux groove I and a three-tower reflux groove II, materials in the three-tower reflux groove I are pressurized by a three-tower reflux pump I and then are sent into the purification tower to be totally refluxed, materials in the three-tower reflux groove II are sent into the dehydrogenation tower to be continuously utilized by a three-tower reflux pump II, products produced in a tower kettle of the purification tower are sent to a product tower to be reused by a three-tower tail liquid pump, a part of DMAC is collected by a three-tower side line system and is refluxed as a side line, the other part of DMAC is collected as a finished product, and the products obtained by.
The DMAC product produced by the production process for producing DMAC under the conditions of no catalyst and low pressure has the purity of 99.99 percent and the acid content of less than 10 ppm.
The invention has the advantages that: by utilizing the cyclic utilization of the synthesis system and the rectification system, continuous and repeated synthesis and rectification provide a new method and thought for the transformation of DMAC production under the conditions of no catalyst and low pressure, the production cost in the DMAC production process under the conditions of no catalyst and low pressure is reduced to a certain extent, the product quality is improved, the productivity is improved, and better economic and social benefits are achieved.
Drawings
FIG. 1 is a process flow of the ingredient synthesis system of the present invention.
FIG. 2 shows the process flow of the rectification column system and the flow-through column system in the invention.
FIG. 3 is a process flow of a rectification three-tower system in the invention.
Detailed Description
As shown in the figure, the device for producing DMAC under the condition of no catalyst and low pressure comprises a DMAC batching synthesis system and a rectification system, wherein the DMAC batching synthesis system comprises a raw material batching system and a reaction system communicated with the batching system, the rectification system comprises a first rectification tower system communicated with the reaction system, a second rectification tower system communicated with the first rectification tower system, a third rectification tower system communicated with the second rectification tower system and a DMAC product output from the third rectification tower system, the reaction system comprises a reactor 1, a preheating and heating system 2 is arranged at the lower part of the reactor 1, a condensation and liquefaction cyclic utilization system 3 is arranged at the upper part of the reactor 1, the batching system comprises acetic acid and DMA, the acetic acid is provided by an acetic acid A tank 4 and an acetic acid B tank 5, and the DMA is provided by a DMA A tank 6 and a DMA B tank 7 from a methylamine working section; the rectification one-tower system comprises a dehydrogenation tower 8 and a one-tower reboiler communicated with the lower part of the dehydrogenation tower 8, the top of the dehydrogenation tower 8 is also provided with a tower heat exchanger 10, the tower heat exchanger 10 is connected with a tower condenser 11 at the top of the dehydrogenation tower 8, the outlet of the tower condenser 11 is connected with the inlet of a tower reflux tank 12, the outlet of the tower reflux tank 12 is connected with the inlet of a tower reflux pump 13, the outlet of the tower reflux pump 13 is connected with the top of the dehydrogenation tower 8, and redundant materials in the tower reflux tank 12 are sent to a methylamine production unit through the tower reflux pump 13 to be reused; the rectification second tower system comprises a product tower 14 and a second tower reboiler 15 communicated with the product tower 14, a second tower heat exchanger 16 is arranged at an ejection opening of the product tower 14, a second tower condenser 17 is arranged at an outlet of the second tower heat exchanger 16, a second tower reflux groove 18 is arranged at an outlet of the second tower condenser 17, a material is sent to the top of the product tower 14 from an outlet of the second tower reflux groove 18 through a second tower reflux pump 19, and redundant material in the second tower reflux groove 18 is sent to a rectification third tower system, the bottom of the product tower 14 is also provided with a two-tower kettle cooler 20, the two-tower kettle cooler 20 sends tower kettle materials to a batching system through a two-tower tail liquid pump 21, redundant tail liquid of the two-tower kettle cooler 20 is discharged to a heavy component tank, the rectification second-tower system is also provided with a second-tower vacuum tank 22, the inlet of the second-tower vacuum tank 22 is communicated with a second-tower condenser 17 and a second-tower reflux groove 18, and the outlet of the second-tower vacuum tank 22 is subjected to water seal removal through a second-tower vacuum pump 23; the rectifying three-tower system comprises a purifying tower 24 and a three-tower reboiler 25 connected with the purifying tower 24, wherein a three-tower condenser I26 is arranged at an ejection opening of the purifying tower 24, the three-tower condenser I26 is communicated with a three-tower condenser II 27, an outlet of the three-tower condenser I26 is connected with a three-tower reflux tank I28, and the three-tower reflux tank I28 is connected with the top of the purifying tower 24 through a three-tower reflux pump I29; the outlet of the three-tower condenser II 27 is connected with the three-tower reflux tank II 30, the three-tower reflux tank II 30 is connected with the inlet of the dehydrogenation tower 8 through a three-tower reflux pump II 31, the purification tower 24 is further provided with a lateral line system, the lateral line system comprises a lateral line outlet arranged on one side of the top of the purification tower 24 and a lateral line condenser 32 connected with the lateral line outlet, the outlet of the lateral line condenser 32 is connected with the lateral line reflux tank 33, the lateral line reflux tank 33 is communicated with a lateral line inlet arranged on the top of the purification tower 24 through a lateral line pump 34, the redundant DMAC finished product of the lateral line reflux tank 33 is output to an intermediate tank, the rectification three-tower system is further provided with a three-tower vacuum tank 35, the inlet of the three-tower vacuum tank 35 is communicated with a three-tower condenser I26, a three-tower condenser II 27, a three-tower reflux tank I28 and a three-tower reflux tank II 30, the outlet of the three-tower vacuum tank, the three-tower kettle cooler 37 is connected with the product tower 14 through a three-tower tail liquid pump 38; the two-tower vacuum pump 23 and the three-tower vacuum pump 36 are both gas delivery pumps, and the pressure of the gas delivery pumps is 0-100 Kpa.
A process for the production of a device for the production of DMAC under catalyst-free, low-pressure conditions, comprising the steps of:
(1) compounding ingredients: respectively pumping acetic acid and DMA from a batching system to a DMAC reaction system to react at 220 ℃ and 3.2MPa (8 hours are needed for early production, continuous feeding and discharging are normally carried out), condensing unreacted materials from the top of a reactor through a condensation liquefaction circulating system, returning the materials from the bottom of the reactor to participate in the reaction again, and feeding the crude products from the reactor into a rectification tower system by pressure difference;
(2) and (3) preparing a finished product by rectification and purification: the crude product from the reactor enters a dehydrogenation tower, light components in the dehydrogenation tower flow out from the tower top to a tower condenser to be condensed, distillate flows back to the dehydrogenation tower through a tower reflux groove and a tower reflux pump to regulate the temperature of the upper middle part of the dehydrogenation tower, when the liquid level of the tower reflux groove is more than 10%, redundant materials in the tower reflux groove of the first tower are sent to a methylamine production unit through the tower reflux pump to be reused, the mixture at the bottom of the dehydrogenation tower is sent to a product tower through pressure difference, light components DMAC in the product tower are condensed through a tower top and a second tower condenser to enter a second tower reflux groove, one part of materials in the tower reflux groove of the second tower are sent to the product tower through a second tower reflux pump to be refluxed, the other part of materials are collected to a purification tower, the tower bottom cooler of the second tower sends the tower bottom materials to a batching system through a second tower tail liquid pump and then enters the reactor to continue to react, and redundant tail liquid of the; light component DMAC in the purification tower is condensed by a tower top three-tower condenser I and a three-tower condenser II and respectively enters a three-tower reflux groove I and a three-tower reflux groove II, materials in the three-tower reflux groove I are pressurized by a three-tower reflux pump I and then are sent into the purification tower to be totally refluxed, materials in the three-tower reflux groove II are sent into the dehydrogenation tower to be continuously utilized by a three-tower reflux pump II, products produced in a tower kettle of the purification tower are sent to a product tower to be reused by a three-tower tail liquid pump, a part of DMAC is collected by a three-tower side line system and is refluxed as a side line, the other part of DMAC is collected as a finished product, and the products obtained by.
The DMAC product produced by the production process for producing DMAC under the conditions of no catalyst and low pressure has the purity of 99.99 percent and the acid content of less than 10 ppm.
When the device is used, raw material acetic acid and raw material DMA from a batching system are respectively pumped to a DMAC reactor, the reaction temperature is 220 ℃, the reaction pressure is 3.2MPa, unreacted DMA and the like are condensed by a condenser from the top of the reactor and then return to the bottom of the reactor to participate in the reaction again, a crude product mixture from the reactor enters a dehydrogenation tower of a rectification first tower system through discharge by pressure difference, light components such as DMA and water are separated from the top of the tower in the dehydrogenation tower, the tower top material is condensed by a dehydrogenation tower condenser and enters a distillate first tower reflux tank, part of the tower reflux tank material enters the dehydrogenation tower as reflux after being pressurized by a first tower reflux pump to adjust the temperature of the upper middle part of the dehydrogenation tower, when the tower reflux tank reaches a certain liquid level, the material containing DMA, water and a small amount of TMA is sent to methylamine for treatment by the first tower reflux pump, and the mixture such as DMAC, MMAC and the like at the bottom of the dehydrogenation tower enters a product tower of a rectification second tower system by pressure, the product tower is controlled by a vacuum pump to operate under a vacuum condition, light component DMAC is condensed by a tower top condenser and enters a two-tower reflux groove, part of materials in the two-tower reflux groove is pressurized by a two-tower reflux pump and then is sent into the product tower as reflux, the other part of the materials is extracted to a purification tower, acetic acid and DMAC form an azeotrope in the product tower and are concentrated at the bottom of the product tower together with high-boiling-point MMAC, the concentrated mixture of the acetic acid and the MMAC circulates to an inlet of an acetic acid pump at a certain speed and enters a reactor for continuous reaction, MMAC generated in the process is accumulated at the bottom of the product tower, so the MMAC must be periodically discharged from the system, the discharged heavy components are treated, the light component DMAC in the purification tower is condensed by a tower top three-tower condenser I and a three-tower condenser II and respectively enters a three-tower reflux groove I and a three-tower reflux groove II, the materials in the three-tower reflux groove, the material in the three-tower reflux tank II is sent into the dehydrogenation tower for continuous utilization through the three-tower reflux pump II, the product produced in the tower bottom of the purification tower is sent to the product tower for reuse through the three-tower tail liquid pump, acetic acid and DMAC form an azeotrope in the purification tower and are concentrated together with the DMAC at the bottom of the purification tower, the concentrated acetic acid and DMAC mixture circulates to the product tower at a certain speed, one part of DMAC is collected by the side line of the purification tower and is used as the side line for reflux, the other part is collected as the finished product DMAC, the product obtained by rectification is sent into the product tank, the synthesis system and the rectification system realize the recycling of the material, the product quality and the yield are improved, the product purity can be improved to 99.99%, the acid content is less than 10ppm, and.
Claims (7)
1. An apparatus for the production of DMAC under catalyst-free, low pressure conditions, comprising: including DMAC batching synthetic system and rectification system, DMAC batching synthetic system includes raw materials batching system and with the reaction system of batching system UNICOM, the rectification system includes the first tower system of rectification with reaction system intercommunication, with the second tower system of rectification of a rectification tower system UNICOM, with the three tower systems of rectification of two tower system UNICOMs to and from the DMAC product of three tower system outputs of rectification, reaction system includes the reactor, and the reactor lower part is equipped with preheating and heating system, and reactor upper portion is equipped with the condensation liquefaction cyclic utilization system.
2. The apparatus for the catalyst-free, low pressure production of DMAC of claim 1, wherein: the rectifying tower system comprises a dehydrogenation tower and a tower reboiler communicated with the lower part of the dehydrogenation tower, the top of the dehydrogenation tower is also provided with a tower heat exchanger, the tower heat exchanger is connected with a tower condenser on the top of the dehydrogenation tower, the outlet of the tower condenser is connected with the inlet of a tower reflux tank, the outlet of the tower reflux tank is connected with the inlet of a tower reflux pump, the outlet of the tower reflux pump is connected with the top of the dehydrogenation tower, and redundant materials in the tower reflux tank are sent to a methylamine production unit through the tower reflux pump for recycling.
3. The apparatus for the production of DMAC under catalyst-free, low pressure conditions of claim 2, wherein: the rectification two-tower system comprises a product tower and a two-tower reboiler communicated with the product tower, a two-tower heat exchanger is arranged at an outlet of the product tower, a two-tower condenser is arranged at an outlet of the two-tower heat exchanger, a two-tower reflux groove is arranged at an outlet of the two-tower condenser, materials are conveyed to the top of the product tower through a two-tower reflux pump at an outlet of the two-tower reflux groove, the redundant materials in the two-tower reflux groove are conveyed to a rectification three-tower system, a two-tower kettle cooler is further arranged at the bottom of the product tower, the two-tower kettle cooler conveys the tower kettle materials to a batching system through a two-tower tail liquid pump, the redundant tail liquid in the two-tower kettle cooler is discharged to a heavy component tank, a two-tower vacuum tank is further arranged at the rectification two-tower system, the inlet of the two-tower vacuum tank is communicated with the two-tower.
4. The apparatus for the catalyst-free, low pressure production of DMAC of claim 3, wherein: the rectifying three-tower system comprises a purifying tower and a three-tower reboiler connected with the purifying tower, wherein a three-tower condenser I is arranged at an outlet of the top of the purifying tower and communicated with a three-tower condenser II, an outlet of the three-tower condenser I is connected with a three-tower reflux tank I, and the three-tower reflux tank I is connected with the top of the purifying tower through a three-tower reflux pump I; the outlet of the third tower condenser II is connected with a third tower reflux groove II, the third tower reflux groove II is connected with the inlet of the dehydrogenation tower through a third tower reflux pump II, the purifying tower is also provided with a lateral system which comprises a measuring line outlet arranged at one side of the top of the purifying tower and a measuring line condenser connected with the measuring line outlet, the outlet of the measuring line condenser is connected with a measuring line reflux groove, the measuring line reflux groove is communicated with a measuring line inlet arranged at the top of the purifying tower through a measuring line pump, the redundant DMAC finished product of the measuring line reflux groove is output to a middle tank, the rectification three-tower system is also provided with a three-tower vacuum tank, the inlet of the three-tower vacuum tank is communicated with a three-tower condenser I, a three-tower condenser II, a three-tower reflux groove I and a three-tower reflux groove II, the outlet of the three-tower vacuum tank is subjected to water seal removal through a three-tower vacuum pump, the bottom of the purifying tower is provided with a three-tower kettle cooler which is connected with the product tower through a three-tower tail liquid pump.
5. The apparatus for the catalyst-free, low pressure production of DMAC of claim 4, wherein: the two-tower vacuum pump and the three-tower vacuum pump are both gas delivery pumps, and the pressure of the gas delivery pumps is 0-100 Kpa.
6. Process for the production of a device for the production of DMAC under catalyst-free, low pressure conditions according to any one of claims 1 to 5, comprising the following steps:
(1) compounding ingredients: respectively pumping acetic acid and DMA from a batching system to a DMAC reaction system to react for 8 hours at 220 ℃ and 3.2MPa, condensing unreacted materials from the top of the reactor through a condensation liquefaction circulating system, returning the materials from the bottom of the reactor to participate in the reaction again, and feeding the crude products from the reactor into a rectification first-tower system by virtue of pressure difference;
(2) and (3) preparing a finished product by rectification and purification: the crude product from the reactor enters a dehydrogenation tower, light components in the dehydrogenation tower flow out from the tower top to a tower condenser to be condensed, distillate flows back to the dehydrogenation tower through a tower reflux groove and a tower reflux pump to regulate the temperature of the upper middle part of the dehydrogenation tower, when the liquid level of the tower reflux groove is more than 10%, redundant materials in the tower reflux groove are sent to a methylamine production unit through the tower reflux pump to be reused, the mixture at the bottom of the dehydrogenation tower is sent to a product tower through pressure difference, light components DMAC in the product tower are condensed into a second tower reflux groove through a tower top and a second tower condenser, part of materials in the second tower reflux groove are sent to the product tower through a second tower reflux pump to be refluxed, the other part of materials are extracted to a purification tower, the materials in the tower bottom cooler of the second tower are sent to a batching system through a second tower tail liquid pump and then enter the reactor to continue to react, and redundant tail liquid in the tower bottom cooler of the second tower is; light component DMAC in the purification tower is condensed by a tower top three-tower condenser I and a three-tower condenser II and respectively enters a three-tower reflux groove I and a three-tower reflux groove II, materials in the three-tower reflux groove I are pressurized by a three-tower reflux pump I and then are sent into the purification tower to be totally refluxed, materials in the three-tower reflux groove II are sent into the dehydrogenation tower to be continuously utilized by a three-tower reflux pump II, products produced in a tower kettle of the purification tower are sent to a product tower to be reused by a three-tower tail liquid pump, a part of DMAC is collected by a three-tower side line system and is refluxed as a side line, the other part of DMAC is collected as a finished product, and the products obtained by.
7. The catalyst-free, low pressure DMAC production process of claim 6 produces a DMAC product having a purity of 99.99% and an acid content of less than 10 ppm.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112958029A (en) * | 2021-04-02 | 2021-06-15 | 华陆工程科技有限责任公司 | Synthesis reactor and N, N-dimethylacetamide synthesis system |
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| CN202576304U (en) * | 2012-04-27 | 2012-12-05 | 河南骏化发展股份有限公司 | Preparation system of dimethyl acetamide |
| CN104817470A (en) * | 2015-04-14 | 2015-08-05 | 常州冀德环保科技有限公司 | DMAC (dimethylacetamide) or DMF (dimethyl formamide) waste liquid five-tower triple-effect rectification system and recovery method thereof |
| CN104815447A (en) * | 2015-04-14 | 2015-08-05 | 常州冀德环保科技有限公司 | DMAC (dimethylacetamide) or DMF (dimethyl formamide) waste liquid four-tower double-effect rectification system and recovery method thereof |
| CN108299190A (en) * | 2018-03-07 | 2018-07-20 | 福州大学 | A kind of method of separation and azeotropic system |
| CN109438275A (en) * | 2018-12-11 | 2019-03-08 | 河北工业大学 | A method of recycling DMAC from film producing industry waste water |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112958029A (en) * | 2021-04-02 | 2021-06-15 | 华陆工程科技有限责任公司 | Synthesis reactor and N, N-dimethylacetamide synthesis system |
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