CN219631290U - Production system of glutaronitrile - Google Patents

Production system of glutaronitrile Download PDF

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Publication number
CN219631290U
CN219631290U CN202321330053.0U CN202321330053U CN219631290U CN 219631290 U CN219631290 U CN 219631290U CN 202321330053 U CN202321330053 U CN 202321330053U CN 219631290 U CN219631290 U CN 219631290U
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reactor
glutaronitrile
plate
separation tower
column
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陈恩之
苗迎彬
徐淑媛
陈东生
张银杏
张楠
张传礼
高泉
陈桐
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Chongqing Huafeng Polyamide Co ltd
CHONGQING HUAFON CHEMICAL CO LTD
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Chongqing Huafeng Polyamide Co ltd
CHONGQING HUAFON CHEMICAL CO LTD
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Abstract

The utility model provides a production system of glutaronitrile, includes reactor, plate separation tower, the reactor is provided with the heater, and the bottom of reactor sets up the feed inlet for link to each other with glutaric acid source, ammonia source, the bin outlet of reactor passes through the pipeline and links to each other with the lateral wall that plate separation tower corresponds the well lower floor column plate, the bottom of plate separation tower sets up the heavy component and arranges the material pipe, to outer heavy component that discharges, and the top of plate separation tower sets up the light component and arranges the material pipe, to outer light component that discharges, and the plate separation tower corresponds the position of well upper column plate and sets up crude product and arrange the material pipe, to outer crude glutaronitrile of discharging, and the plate separation tower corresponds the position of bottom column plate and sets up the back flow, to the reactor feed. The utility model has simple structure and low investment, and can effectively reduce the production cost of glutaronitrile.

Description

Production system of glutaronitrile
Technical Field
The utility model relates to the field of chemical industry, in particular to a production system of glutaronitrile.
Background
Glutaronitrile alias 1, 3-dicyanopropane having the formula NC (CH) 2 ) 3 CN, mainly used as a reagent and a chemical intermediate. The downstream products mainly comprise diethyl glutarate, 1, 5-diaminopentane and the like. Meanwhile, the glutaronitrile can also be added with hydrogen to generate the pentanediamine, and the pentanediamine and the adipic acid are condensed to generate the nylon 56 salt, so that the water absorption, the glass transition temperature, the strength, the softness, the hygroscopicity and the rebound resilience are all superior to those of partial products of nylon 6, nylon 66 and terylene.
Nitriles are generally obtained by reacting halogenated hydrocarbons with cyanide. Glutaronitrile is generally prepared by reacting dibromopropane with sodium cyanide, dissolving sodium cyanide in water, adding an ethanol solution of dibromopropane, cooling, filtering to remove precipitate, extracting mother liquor with ethyl acetate, washing with water, drying with potassium carbonate, recovering ethyl acetate, and distilling the residue under reduced pressure to yield about 80%. However, the process essentially uses the virulent substances of sodium cyanide and hydrogen cyanide, has higher requirements on the condition of the whole equipment, and has higher reaction temperature generally and is easy to cause side reactions.
The glutaronitrile may be produced with dimethyl glutarate and ammonia water to produce amide, and the reacted solid product may be dewatered with dewatering agent to produce glutaronitrile. The glutaronitrile is then adsorbed by active carbon, and is purified by light component removal, heavy component removal and rectification. However, the process flow of the technology is longer, so that the equipment investment is larger, and the economy is poor.
Therefore, how to design an economical synthesis system with short process flow and low equipment investment is a problem to be solved by the technicians in the field.
Disclosure of Invention
The utility model aims to provide a production system of glutaronitrile, which has simple structure and low investment and can effectively reduce the production cost of glutaronitrile.
The technical scheme for realizing the aim of the utility model is as follows: the utility model provides a production system of glutaronitrile, includes reactor, plate separation tower, the reactor is provided with the heater, and the bottom of reactor sets up the feed inlet for link to each other with glutaric acid source, ammonia source, the bin outlet of reactor passes through the pipeline and links to each other with the lateral wall that plate separation tower corresponds the well lower floor column plate, the bottom of plate separation tower sets up the heavy component and arranges the material pipe, to outer heavy component that discharges, and the top of plate separation tower sets up the light component and arranges the material pipe, to outer light component that discharges, and the plate separation tower corresponds the position of well upper column plate and sets up crude product and arrange the material pipe, to outer crude glutaronitrile of discharging, and the plate separation tower corresponds the position of bottom column plate and sets up the back flow, to the reactor feed.
Further, still include decanter, dehydrator, light ends removal tower, crude product row material pipe is to the feed of decanter, sets up the cooler on this crude product row material pipe, the light phase export of decanter links to each other with the top feed inlet of dehydrator through the pipeline, the bottom bin outlet of dehydrator passes through the pipeline and feeds light ends removal tower.
Further, the heavy phase outlet of the decanter feeds a plate separation column.
Further, the bottom of the dehydrator is provided with an air inlet for being connected with a nitrogen source, and the top of the light component removing tower is connected with a negative pressure source.
Further, the device also comprises a heavy removal tower, wherein a feed inlet of the heavy removal tower is connected with a bottom discharge outlet of the light removal tower, and the top of the heavy removal tower is connected with a vacuum source.
The technical scheme has the following beneficial effects:
1. the production system of glutaronitrile comprises a reactor and a plate-type separation tower, wherein the reactor is used for providing a reaction space, and the plate-type separation tower is used for separating and purifying target products. The reactor is provided with a heater, the bottom of the reactor is provided with a feed inlet for connecting with a glutaric acid source and an ammonia source, the temperature is controlled by the heater arranged in the reactor, glutaric acid and excessive ammonia are pre-reacted at a lower temperature to generate ammonium salt of glutaric acid, the temperature is raised to a higher temperature for nitrifying, the target product of glutaronitrile is obtained, the generation of byproducts is reduced, coking is avoided, the long-time normal work of the reactor is ensured, and the requirement of industrial continuous production is met. The discharge port of the reactor is connected with the side wall of the plate-type separation tower corresponding to the middle-lower layer tower plate through a pipeline, the bottom of the plate-type separation tower is provided with a heavy component discharge pipe, heavy components which mainly comprise high boiling point heavy components such as glutaramide and dimer are discharged outwards, the top of the plate-type separation tower is provided with a light component discharge pipe, light components which mainly comprise ammonia, water and cyclopentanone are discharged outwards, the position of the plate-type separation tower corresponding to the middle-upper layer tower plate is provided with a crude product discharge pipe, the position of the plate-type separation tower corresponding to the bottom layer tower plate is provided with a return pipe, the position of the plate-type separation tower corresponding to the bottom layer tower plate is provided with a material which is partially incompletely dehydrated, and the material is returned to the reactor for continuous reaction, so that the utilization efficiency of the material is improved.
2. The production system of glutaronitrile of the utility model also comprises a decanter, a dehydrator and a light component removing tower, wherein the decanter, the dehydrator and the light component removing tower are all used for removing impurities in crude glutaronitrile so as to obtain the glutaronitrile product with higher purity. The temperature of the decanter is controlled to be 15-65 ℃, so that part of byproduct substances are dissolved in water, and separation of an oil phase and a water phase is facilitated; the temperature of the dehydrator is controlled to be 115-145 ℃, nitrogen is introduced into the bottom of the dehydrator and is in countercurrent contact with the crude glutaronitrile, so that the water content in the crude glutaronitrile can be effectively reduced, the purity of the glutaronitrile after impurity removal is improved, in addition, the introduced nitrogen can also form a protective atmosphere in the dehydrator, the further side reaction of the crude glutaronitrile at a higher temperature is avoided to generate byproducts, and the yield and quality of the glutaronitrile are ensured.
The experiment of the applicant proves that the glutaronitrile prepared by the production system has the purity of more than or equal to 95 percent and the water content of less than or equal to 0.2 percent, and compared with the traditional production method, the method can effectively utilize the diacid by-produced by adipic acid and perfect the whole industrial chain of nylon.
Further description is provided below with reference to the drawings and detailed description.
Drawings
Fig. 1 is a schematic connection diagram of example 1.
In the drawing, 1 is a reactor, 2 is a plate type separation tower, 3 is a reflux pipe, 4 is a decanter, 5 is a dehydrator, 6 is a light component removal tower, 7 is a cooler, 8 is an air inlet, and 9 is a heavy component removal tower.
Detailed Description
In the utility model, the adipic acid content in the mixed acid is 12-36%, the glutaric acid content is 28-62%, the succinic acid content is 18-26%, and the water content is less than or equal to 1.5% wt; liquid ammonia is referred to GB/T536 superior standard.
Example 1
Referring to fig. 1, the glutaronitrile production system includes a reactor 1, a tray separation column 2. The reactor 1 is a tubular reactor, a heat exchange jacket is arranged in the middle section of the reactor, and heat conduction oil is used for heating. The bottom of the reactor 1 is provided with a feed inlet which is used for being connected with a glutaric acid source and an ammonia gas source. The discharge port on the upper part of the reactor 1 is connected with the side wall of the tray at the lowest layer of the straight pipe section of the plate-type separation tower through a pipeline, the bottom of the plate-type separation tower 2 is provided with a heavy component discharge pipe, heavy components are discharged outwards, the top of the plate-type separation tower 2 is provided with a light component discharge pipe, the light components are discharged outwards, the plate-type separation tower is provided with a crude product discharge pipe corresponding to a tray layer which mainly contains crude nitrile and does not contain water in the tower, the crude glutaronitrile is discharged outwards, the plate-type separation tower is provided with a return pipe 3 corresponding to the tray at the bottom layer, and the reactor 1 is fed. In this embodiment, the system further comprises a decanter 4, a dehydrator 5, a light-removal column 6 and a heavy-removal column 9, wherein the raw product discharging pipe is used for feeding the decanter 4, a cooler 7 is arranged on the raw product discharging pipe, a light-phase outlet of the decanter 4 is connected with a top feeding hole of the dehydrator 5 through a pipeline, and a heavy-phase outlet of the decanter is used for recycling materials to the system, wherein part of the materials are returned to the plate type separation column. The bottom discharge port of the dehydrator 5 is used for feeding the light component removing tower 6 through a pipeline, a flash tank is arranged on the pipeline, the flash tank can enter the light component removing tower through an upper layer of tower plate, a middle layer of tower plate and a lower layer of tower plate after flash evaporation is balanced, the bottom of the dehydrator 5 is provided with an air inlet 8 which is used for being connected with a nitrogen source, the top of the light component removing tower 6 is connected with a negative pressure source, the feed port of the heavy component removing tower 9 is connected with the bottom discharge port of the light component removing tower 6, and the top of the heavy component removing tower 9 is connected with a vacuum source.
Example 2
A method for producing glutaronitrile using the production system of example 1, comprising the steps of:
the molten glutaric acid with a flow rate of 1500kg/h was sent out of the glutaric acid buffer tank and 3.0kg/h of the phosphorus-containing catalyst was mixed homogeneously by means of a mixer at the outlet of the glutaric acid feed pump and sent into the bottom of the reactor. The reactor was charged with 2700kg/h ammonia (molar ratio to glutaric acid 14:1, i.e. 7-fold excess of ammonia) and the pre-reaction was carried out at 240℃and 46 KPaG. And (3) continuously feeding the aminated material into the middle section of the reactor, and heating to 290 ℃ by using heat conducting oil steam to dehydrate to generate glutaronitrile.
The crude glutaronitrile enters the lower half part of a plate-type separation tower to be separated, the bottom pressure of the tower is controlled at 26KPaG, and a pipeline at the bottom of the plate-type separation tower is circulated by a pump and then sent out to treat heavy components. The top of the plate-type separation tower can separate light components such as ammonia, water, cyclopentanone and the like, and the temperature of the top of the tower is controlled at 80 ℃. Crude glutaronitrile is taken out from the middle upper part of the plate-type separation tower, and the flow is 1175kg/h.
The crude nitrile from the plate separation column contains a portion of the wash water, which is condensed and washed, and most of the water is separated by a decanter. Wherein the upper layer separates out oil phase, and the temperature is controlled at 28 ℃; separating water phase and water-soluble substances such as glutarimide from the lower layer, and recycling the water-soluble substances to the system.
The oily substances containing glutaronitrile enter the upper section of a dehydrator, water, ammonia, cyclopentanone and other low-boiling-point organic substances are separated from the top, and the dehydrator is heated by steam, and the temperature is controlled at 132 ℃. To reduce the water content in the organic matter, nitrogen is introduced from the bottom of the dehydrator, and the flow rate is 420Nm 3 And/h is countercurrently contacted with the crude nitrile.
The water content of the material flowing out from the bottom of the dehydrator was 0.05% by weight, and the material was sent to a light ends column by pumping. According to the different fluid compositions, the materials are sent to the upper layer column plate after flash evaporation balance. The top of the light component removal tower is connected with a vacuum system, and the operating pressure is-98 KPaG. The light component substances extracted from the upper part of the light component removing tower are discharged out of the system after being further separated. The temperature of the tower kettle is controlled at 190 ℃, and the tower kettle mainly contains components such as glutaronitrile and the like.
The materials flowing out from the bottom of the light component removing tower are pumped to the heavy component removing tower. According to the different fluid compositions, the materials are sent to the upper layer tower plate. The top of the heavy-removal tower is connected with a vacuum system, and the operating pressure is-97.5 KPaG. The upper part of the weight removing tower mainly extracts glutaronitrile and sends the glutaronitrile to a finished product storage tank. The temperature of the tower kettle is controlled at 185 ℃, and heavy component substances separated from the tower kettle are discharged out of the system after further separation.
The purity of the obtained glutaronitrile is 95.53% and the comprehensive yield is 25-60% through detection.
Example 3
A method for producing glutaronitrile using the production system of example 1, comprising the steps of:
the molten glutaric acid with flow rate of 1800kg/h was sent out of the glutaric acid buffer tank and 3.6kg/h of the phosphorus-containing catalyst was mixed homogeneously by means of a mixer at the outlet of the glutaric acid feed pump and sent into the bottom of the reactor. 2780kg/h of ammonia (molar ratio to glutaric acid 12:1, i.e. 6 times excess of ammonia) was fed into the reactor and the pre-reaction was carried out at 235℃and 48 KPaG. And (3) continuously feeding the aminated material into the middle section of the reactor, heating to 293 ℃ by using heat conducting oil steam, and dehydrating to generate glutaronitrile.
The crude glutaronitrile enters the lower half part of the separation tower to be separated, the pressure at the bottom of the tower is controlled at 28KPaG, and a pipeline at the bottom of the separation tower is circulated by a pump and then sent out to treat heavy components. The top of the separation tower can separate light components such as ammonia, water, cyclopentanone and the like, and the temperature of the top of the separation tower is controlled at 84 ℃. Crude glutaronitrile is taken out from the middle upper part of the separation tower, and the flow is 1410kg/h.
The crude nitrile from the separation column contains a portion of the wash water, which is condensed and washed, and most of the water is separated by a decanter. Wherein the upper layer separates out oil phase, and the temperature is controlled at 26 ℃; separating water phase and water-soluble substances such as glutarimide from the lower layer, and recycling the water-soluble substances to the system.
The oily substances containing glutaronitrile enter the upper section of a dehydrator, water, ammonia, cyclopentanone and other low-boiling-point organic substances are separated from the top, and the dehydrator is heated by steam, and the temperature is controlled at 136 ℃. To reduce the water content in the organic matter, nitrogen is introduced from the bottom of the dehydrator, and the flow rate is 460Nm 3 And/h counter-current to the crude nitrile.
The water content of the material flowing out from the bottom of the dehydrator was 0.03 wt%, and the material was sent to a light component removing tower by pumping. According to the different fluid compositions, the materials are sent to the lower layer tower plate after flash evaporation balance. The top of the light component removing tower is connected with a vacuum system, and the operating pressure is-99 KPaG. The light component substances extracted from the upper part of the light component removing tower are discharged out of the system after being further separated. The temperature of the tower bottom is controlled at 192 ℃, and the tower bottom mainly contains components such as glutaronitrile and the like.
The materials flowing out from the bottom of the light component removing tower are pumped to the heavy component removing tower. According to the different fluid compositions, the materials are sent to the middle layer tower plate. The top of the heavy-removal tower is connected with a vacuum system, and the operating pressure is-98.5 KPaG. The upper part of the weight removing tower mainly extracts glutaronitrile and sends the glutaronitrile to a finished product storage tank. The temperature of the tower kettle is controlled at 187 ℃, and heavy component substances separated from the tower kettle are discharged out of the system after further separation.
The purity of the obtained glutaronitrile is 95.48% and the comprehensive yield is 25-60% through detection.
Example 4
A method for producing glutaronitrile using the production system of example 1, comprising the steps of: the molten glutaric acid with a flow rate of 2200kg/h was sent out of the glutaric acid buffer tank and evenly mixed with 4.4kg/h of the phosphorus-containing catalyst by means of a mixer at the outlet of the glutaric acid feed pump, and sent into the bottom of the reactor. The reactor was charged with 2830kg/h of ammonia (molar ratio to glutaric acid 10:1, i.e. 5-fold excess of ammonia) and the pre-reaction was carried out at 230℃and 50 KPaG. And (3) continuously feeding the aminated material into the middle section of the reactor, and heating to 296 ℃ by using heat conducting oil steam to dehydrate to generate glutaronitrile.
The crude glutaronitrile enters the lower half part of the separation tower to be separated, the bottom pressure of the tower is controlled at 30KPaG, and a pipeline at the bottom of the separation tower is circulated by a pump and then sent out to treat heavy components. The top of the separation tower can separate light components such as ammonia, water, cyclopentanone and the like, and the temperature of the top of the separation tower is controlled at 88 ℃. Crude glutaronitrile is taken out from the middle upper part of the separation tower, and the flow is 1724kg/h.
The crude nitrile from the separation column contains a portion of the wash water, which is condensed and washed, and most of the water is separated by a decanter. Wherein the upper layer separates out oil phase, and the temperature is controlled at 24 ℃; separating water phase and water-soluble substances such as glutarimide from the lower layer, and recycling the water-soluble substances to the system.
The oily substances containing glutaronitrile enter the upper section of a dehydrator, water, ammonia, cyclopentanone and other low-boiling-point organic substances are separated from the top, and the dehydrator is heated by steam, and the temperature is controlled at 140 ℃. To reduce the water content in the organic matter, nitrogen is introduced from the bottom of the dehydrator, and the flow rate is 500Nm 3 And/h counter-current to the crude nitrile.
The water content of the material flowing out from the bottom of the dehydrator was 0.04% by weight, and the material was sent to the light component removing column by pumping. According to the different fluid compositions, the materials are sent to the middle layer tower plate after flash evaporation and balance. The top of the light component removal tower is connected with a vacuum system, and the operating pressure is-98.5 KPaG. The light component substances extracted from the upper part of the light component removing tower are discharged out of the system after being further separated. The temperature of the tower bottom is controlled at 195 ℃, and the tower bottom mainly contains components such as glutaronitrile and the like.
The materials flowing out from the bottom of the light component removing tower are pumped to the heavy component removing tower. Depending on the composition of the fluid, the material is fed to the lower tray. The top of the heavy-removal tower is connected with a vacuum system, and the operating pressure is-98 KPaG. The upper part of the weight removing tower mainly extracts glutaronitrile and sends the glutaronitrile to a finished product storage tank. The temperature of the tower kettle is controlled at 190 ℃, and heavy component substances separated from the tower kettle are discharged out of the system after further separation.
The purity of the obtained glutaronitrile is 96.27% and the comprehensive yield is 25-60% through detection.
Compared with the traditional method for synthesizing glutaronitrile, the production method of the patent application provides a new industrialized production method.

Claims (5)

1. The utility model provides a production system of glutaronitrile, its characterized in that, includes reactor (1), plate separation tower (2), reactor (1) is provided with the heater, and the bottom of reactor (1) sets up the feed inlet for link to each other with glutaric acid source, ammonia source, the bin outlet of reactor (1) passes through the pipeline and links to each other with the lateral wall that plate separation tower corresponds the middle-lower floor column plate, the bottom of plate separation tower (2) sets up heavy component and arranges the material pipe, to outer heavy component of discharging, and the top of plate separation tower (2) sets up the light component and arranges the material pipe, to outer light component of discharging, and plate separation tower corresponds the position of well upper column plate and sets up crude product and arrange the material pipe, to outer crude glutaronitrile of discharging, plate separation tower corresponds the position of bottom column plate and sets up back flow (3), to reactor (1) feed.
2. The production system according to claim 1, further comprising a decanter (4), a dehydrator (5) and a light ends removal column (6), wherein the raw product discharge pipe feeds the decanter (4), a cooler (7) is arranged on the raw product discharge pipe, a light phase outlet of the decanter (4) is connected with a top feed inlet of the dehydrator (5) through a pipeline, and a bottom discharge outlet of the dehydrator (5) feeds the light ends removal column (6) through a pipeline.
3. Production system according to claim 2, characterized in that the heavy phase outlet of the decanter feeds a plate separation column (2).
4. The production system according to claim 2, characterized in that the bottom of the dewaterer (5) is provided with an air inlet (8) for connection to a nitrogen source, the top of the light ends removal column (6) being connected to a negative pressure source.
5. The production system of claim 2, further comprising a de-weight column (9), wherein a feed inlet of the de-weight column (9) is connected to a bottom discharge outlet of the de-weight column (6), and wherein a top of the de-weight column (9) is connected to a vacuum source.
CN202321330053.0U 2023-05-29 2023-05-29 Production system of glutaronitrile Active CN219631290U (en)

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