Maleic anhydride hydrogenation reaction system

Abstract

The utility model relates to the technical field of chemical reaction equipment provides a maleic anhydride hydrogenation reaction system, include: maleic anhydride supply pipeline, hydrogen supply pipeline, reaction unit and separation device. Maleic anhydride supply pipeline is used to supply maleic anhydride, hydrogen supply pipeline is used to supply hydrogen, reaction unit is linked with maleic anhydride supply pipeline and hydrogen supply pipeline respectively, is used to carry out catalysis to the mixture of maleic anhydride and hydrogen, to generate reaction product, separation device includes separation subassembly, condensing subassembly, first liquid discharge pipeline and second liquid discharge pipeline, separation subassembly links with reaction unit, condensing subassembly and second liquid discharge pipeline respectively, condensing subassembly is connected with first liquid discharge pipeline. The maleic anhydride hydrogenation reaction system of the utility model can realize the co-production of rich THF solution and BDO product, and can extract THF in gas phase product with the help of condensing subassembly, make it condense into rich THF solution, thereby improve the yield of the solution.

Description

Technical Field

[0001] This utility model relates to the field of chemical reaction equipment technology, and in particular to a maleic anhydride hydrogenation reaction system. Background Technology

[0002] 1,4-Butanediol (BDO) and its derivatives are high-value-added fine chemical products. Currently, the preparation of 1,4-butanediol typically employs a maleic anhydride hydrogenation catalytic method, among which liquid-phase hydrogenation has the advantage of simple process flow and is gradually becoming the mainstream process. Since its successful initial development in the early 1970s, the maleic anhydride liquid-phase hydrogenation technology has long used a multi-step hydrogenation process: the first step uses Raney-Ni as a catalyst to hydrogenate maleic anhydride (or a solution of maleic anhydride's γ-butyrolactone) at 210–280℃ and 6–12 MPa to generate succinic anhydride, with a relatively fast reaction rate; the second step requires replacing the catalyst with a diatomaceous earth catalyst (or a palladium-rhenium, copper-chromium, etc.) supported on nickel-cobalt-thorium active components, and continuously hydrogenating at 250℃ and 10 MPa for 6 hours to further convert succinic anhydride into BDO, while simultaneously generating byproducts such as THF and γ-butyrolactone. While this traditional multi-step process can achieve the co-production of BDO, THF (tetrahydrofuran), and γ-butyrolactone by adjusting the conditions, and the maleic anhydride conversion rate can reach 100% and the selectivity exceeds 98%, existing BDO production equipment lacks the extraction and collection of derivatives (mainly tetrahydrofuran). Utility Model Content

[0003] This invention provides a maleic anhydride hydrogenation reaction system to solve the problem that existing BDO production equipment lacks the ability to extract and collect derivatives (mainly tetrahydrofuran).

[0004] This invention provides a maleic anhydride hydrogenation reaction system, comprising: Maleic anhydride supply line, used to supply maleic anhydride; Hydrogen supply pipeline, used to supply hydrogen gas; The reaction apparatus is connected to the maleic anhydride supply line and the hydrogen supply line, respectively, and is used to catalyze the mixture of maleic anhydride and hydrogen to generate reaction products; A separation device includes a separation component, a condensation component, a first drain line, and a second drain line; the separation component is connected to the reaction device, the condensation component, and the second drain line respectively; the condensation component is connected to the first drain line. The separation component is used to separate the reaction products into a gaseous mixture and a BDO product. The gaseous mixture is passed into the condensation component to obtain a THF-rich solution. The THF-rich solution is passed into the first drain line, and the BDO product is passed into the second drain line. The condensation component is used to condense the gaseous mixture and pass the condensed THF-rich solution into the first drain line.

[0005] According to the maleic anhydride hydrogenation reaction system of this invention, the separation component includes: A cold high-efficiency separator, connected to the reaction apparatus, is used to separate the reaction products into hydrogen-rich gas and liquid products; The distillation column is connected to the cold high-efficiency separation tank, the condensation assembly, the first drain line, and the second drain line, respectively. The distillation column is used to separate the liquid phase product into the gas phase mixture and the BDO product.

[0006] According to the maleic anhydride hydrogenation reaction system of this utility model, the condensation assembly includes: a condenser, a reflux tank, and a reflux pump connected in sequence; The condenser is connected to the distillation column and is used to condense the gas-phase mixture to form the THF-rich solution and non-condensable gas. The reflux pump is connected to the distillation column and the first discharge line, respectively, and is used to pass a portion of the THF-rich solution in the reflux tank into the first discharge line, and to pass another portion of the THF-rich solution into the distillation column.

[0007] The maleic anhydride hydrogenation reaction system according to this invention also includes: The hydrogen circulation pipeline includes a first burner and a first buffer tank, a first compressor, and a second buffer tank connected in sequence. The second buffer tank and the first burner are connected to the cold high-efficiency separator. The second buffer tank is used to receive the hydrogen-rich gas separated by the cold high-efficiency separator. The first burner is used to burn the hydrogen-rich gas. The second buffer tank is connected to the reaction device.

[0008] According to the maleic anhydride hydrogenation reaction system of this utility model, the hydrogen supply pipeline includes a second burner and a filter, a third buffer tank, a second compressor, and a fourth buffer tank connected in sequence. The second burner is connected to the filter. The filter is used to connect to an external hydrogen supply pipeline to filter external hydrogen gas and pass the filtered impurities into the second burner and the filtered hydrogen gas into the third buffer tank. The fourth buffer tank is connected to the reaction device.

[0009] According to the maleic anhydride hydrogenation reaction system of this utility model, the reaction device includes: a preheater and a reaction assembly connected in sequence; The preheater is connected to the maleic anhydride supply pipeline and the hydrogen supply pipeline, respectively; The reaction assembly and the separation device are connected.

[0010] According to the maleic anhydride hydrogenation reaction system of this utility model, the preheater has a high-temperature side and a low-temperature side, wherein the inlet of the low-temperature side is connected to the maleic anhydride supply pipeline and the hydrogen supply pipeline respectively, and the outlet of the low-temperature side is connected to the inlet of the reaction component; the inlet of the high-temperature side is connected to the outlet of the reaction component, and the outlet of the high-temperature side is connected to the separation device.

[0011] According to the maleic anhydride hydrogenation reaction system of this invention, the reaction components include: The hydrogenation reactor is connected to both the preheater and the separation device. A molten salt circulation pipeline, connected to the hydrogenation reactor, is used to introduce molten salt into the hydrogenation reactor to remove the heat of reaction within the reactor.

[0012] According to the maleic anhydride hydrogenation reaction system of this utility model, a heat dissipation pipeline is provided inside the hydrogenation reactor; The molten salt circulation pipeline includes: Molten salt high-level tank, used for storing molten salt; A molten salt circulation pump is connected to the inlet of the heat dissipation pipeline and the outlet of the molten salt high-level tank, respectively, for feeding the molten salt into the hydrogenation reactor; A steam generator is connected to the outlet of the heat dissipation pipe and the inlet of the molten salt high-level tank, respectively, for introducing external water to dissipate heat from the molten salt.

[0013] According to the maleic anhydride hydrogenation reaction system of this invention, the molten salt circulation pipeline further includes: A molten salt replenishment pipeline is connected to the molten salt high-level tank and is used to supply molten salt to the molten salt high-level tank.

[0014] This invention discloses a maleic anhydride hydrogenation reaction system. Maleic anhydride and hydrogen are introduced into a reaction apparatus for a catalytic reaction to generate a mixed reaction product including BDO and derivatives such as THF and butanol. The reaction product is then passed to a separation component of a separation device. This component separates the reaction product through methods such as vacuum separation and distillation. The separated gaseous product is then passed to a condensation component. A THF-rich solution is passed through a first drain line, and the BDO product is passed through a second drain line. The condensation component further separates the THF from the gaseous product into a solution, which is then passed through the first drain line to increase the yield of the THF-rich solution. The first drain line is used to collect the THF-rich solution, and the second drain line is used to collect the BDO product. As can be seen, this invention's maleic anhydride hydrogenation reaction system can achieve the co-production of BDO and THF using a single reactor and can remove non-condensable gases from THF through the condensation component. This solves the problem in existing BDO production equipment of lacking the extraction and collection of derivatives (mainly tetrahydrofuran). Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a system diagram of the maleic anhydride hydrogenation reaction system provided in this embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the maleic anhydride supply pipeline, hydrogen supply pipeline, and reaction device provided in the embodiments of this utility model.

[0018] Figure 3 This is a schematic diagram of the separation device and hydrogen circulation pipeline provided in this embodiment of the utility model.

[0019] Figure label: 1. Maleic anhydride hydrogenation reaction system; 11. Maleic anhydride supply pipeline; 12. Hydrogen supply pipeline; 121. Second burner; 122. Filter; 123. Third buffer tank; 124. Second compressor; 125. Fourth buffer tank; 13. Reaction apparatus; 131. Preheater; 132. Reaction components; 1321. Hydrogenation reactor; 1322. Molten salt circulation pipeline; 13221. Molten salt high-level tank; 13222. Molten salt circulation pump; 13223. Steam generator; 13224. Molten salt replenishment pipeline; 14. Separation device; 141. Separation assembly; 1411. Cold high-efficiency separation tank; 1412. Distillation column; 142. Condensing assembly; 1421. Condenser; 1422. Reflux tank; 1423. Reflux pump; 143. First drain line; 144. Second drain line; 15. Hydrogen circulation pipeline; 151. First burner; 152. First buffer tank; 153. First compressor; 154. Second buffer tank; 155. Third burner. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] The maleic anhydride hydrogenation reaction system of this application mainly uses liquid-phase hydrogenation of maleic anhydride to prepare BDO. Specifically, the process conditions refer to the hydrogenation chemical reaction between maleic anhydride dissolved in an organic solvent and hydrogen gas under the presence of a solid catalyst. This chemical reaction belongs to a three-phase system of liquid-gas-solid hydrogenation.

[0022] The following is combined Figures 1-3 This invention describes the maleic anhydride hydrogenation reaction system.

[0023] like Figure 1 As shown, this utility model provides a maleic anhydride hydrogenation reaction system 1, including: maleic anhydride supply pipeline 11, hydrogen supply pipeline 12, reaction device 13 and separation device 14. Maleic anhydride supply line 11 is used to supply maleic anhydride; hydrogen supply line 12 is used to supply hydrogen; reaction device 13 is connected to maleic anhydride supply line 11 and hydrogen supply line 12 respectively, and is used to catalyze the mixture of maleic anhydride and hydrogen to generate reaction products; separation device 14 includes separation component 141, condensation component 142, first drain line 143 and second drain line 144; separation component 141 is connected to reaction device 13, condensation component 142 and second drain line 144 respectively; condensation component 142 is connected to first drain line 143; wherein, separation component 141 is used to separate reaction products into gas phase mixture and BDO product, and to pass gas phase mixture into condensation component 142, pass THF-rich solution into first drain line 143, and pass BDO product into second drain line 144; condensation component 142 is used to condense gas phase mixture and pass the condensed THF-rich solution into first drain line 143.

[0024] In this embodiment, both the maleic anhydride supply line 11 and the hydrogen supply line 12 are connected to the reaction apparatus 13 to provide the maleic anhydride and hydrogen required for the reaction. The reaction apparatus 13 provides a reaction site with suitable reaction conditions (including catalyst, reaction temperature, and reaction pressure). Exemplarily, the catalyst can be the catalyst provided in the patent application number 202110616637.3. Under the catalysis of this catalyst, BDO can be generated in one step, and the reaction can be carried out under mild conditions of 200°C and 4.0 MPa. Compared with conventional processes, this significantly reduces the reaction temperature and pressure, while also enabling a maleic anhydride conversion rate of up to 100% and a BDO selectivity of up to 98.7%.

[0025] The reaction products generated after the hydrogenation of maleic anhydride include BDO and derivatives such as THF and butanol. The reaction products generated in the reaction apparatus 13 are fed into the separation component 141. The separation component 141 can separate and purify the reaction products by means of vacuum separation, distillation, etc., so that different components in the reaction products are concentrated at different positions in the separation component 141 and discharged from the outlets of the corresponding positions.

[0026] The gaseous product is introduced into the condenser assembly 142, the THF-rich solution is introduced into the first drain line 143, and the BDO product is introduced into the second drain line 144. The high-purity BDO product can be collected through the second drain line 144 for further utilization or sale. The condenser assembly 142 is used to further condense the gaseous product, condensing the THF in the product into a solution and removing non-condensable gases from the THF, which are then introduced into the first drain line 143. The first drain line 143 is used for centralized collection of the THF-rich solution.

[0027] The maleic anhydride hydrogenation reaction system 1 of this invention catalyzes the reaction by introducing maleic anhydride and hydrogen into a reaction device 13 to generate a mixed reaction product including BDO and derivatives such as THF and butanol. The reaction product is then introduced into a separation component 141 of a separation device 14. The separation component 141 can separate the reaction product by means of vacuum separation, distillation, etc. The separated gaseous product is introduced into a condensation component 142, the THF-rich solution is introduced into a first drain pipe 143, and the BDO product is introduced into a second drain pipe 144. The condensation component 142 can further separate the THF in the gaseous product to form a solution and introduce it into the first drain pipe 143. The first drain pipe 143 is used to collect the THF-rich solution, and the second drain pipe 144 is used to collect the BDO product. As can be seen from the above, the maleic anhydride hydrogenation reaction system 1 of this utility model is a one-step hydrogenation device for BDO preparation, which simultaneously achieves the co-production of THF and BDO. It can also extract the THF-rich solution from the gaseous product through the condensation component 142 to increase the yield of the THF-rich solution, thus solving the problems of complex BDO production equipment and lack of extraction and collection of derivative products (mainly tetrahydrofuran) in the prior art.

[0028] Optionally, the first drain line 143 can be connected to a purification system so that the THF-rich solution can be introduced into the purification system, which can purify the THF-rich solution to obtain a THF solution with higher purity.

[0029] The maleic anhydride supply line 11 includes a maleic anhydride buffer tank, a feed pump, and a maleic anhydride filter connected in sequence. The maleic anhydride buffer tank is used to receive and buffer the maleic anhydride introduced from the outside. The feed pump is used to pump the maleic anhydride into the maleic anhydride filter. After filtering the maleic anhydride, it is introduced into the reaction device 13 for reaction.

[0030] Specifically, in some embodiments, such as Figure 3 As shown, the separation assembly 141 includes a cold high-efficiency separation tank 1411 and a distillation column 1412. The cold high-efficiency separation tank 1411 is connected to the reaction device 13 and is used to separate the reaction products into hydrogen-rich gas and liquid products. The distillation column 1412 is connected to the cold high-efficiency separation tank 1411, the condensation assembly 142, the first drain line 143 and the second drain line 144, respectively. The distillation column 1412 is used to separate the liquid products into a gas mixture and BDO products.

[0031] In this embodiment, the cold high-pressure separator 1411 is directly connected to the reaction apparatus 13 to receive the reaction products generated by the catalytic reaction in the reaction apparatus 13. The cold high-pressure separator 1411 is a key piece of equipment in high-pressure hydrogenation units such as hydrocracking and hydrorefining. It is used to separate the reactor effluent into a gaseous mixture (mainly composed of unreacted hydrogen) and liquid products in one step under the conditions of "lower temperature + high pressure". The high-temperature and high-pressure reaction products are cooled to a certain temperature by the cold high-pressure separator 1411 and the high-pressure air cooler and then enter the cold high-pressure separator 1411. Under the conditions of reduced pressure and lower temperature, the solubility of hydrogen decreases, and most of the hydrogen quickly escapes to the upper gas phase to form a gaseous mixture. The liquid products include THF, BDO, etc., and the liquid products can be fed into the distillation column 1412 for further separation.

[0032] Distillation column 1412 is a sieve tray column, typically composed of multiple horizontal sieve trays, along with gas-liquid guiding and distribution components, and a reboiler at the bottom. Distillation column 1412 (sieve tray column) generates rising vapor through the reboiler at the bottom, which comes into counter-current contact with the descending liquid phase formed by reflux at the top of the column on each sieve tray, undergoing interphase mass transfer. The more volatile components enter the vapor phase, while the less volatile components transfer to the liquid phase, ultimately achieving separation of light and heavy components. The feed inlet is located in the middle of distillation column 1412; the section above the feed inlet further concentrates the more volatile components in the rising vapor and is called the rectification section; the section below the feed inlet extracts the less volatile components from the descending liquid and is called the stripping section. The gas-phase mixture at the top of the column (mainly composed of non-condensable gas and THF) is fed into the condenser assembly 142. The THF is condensed into a solution, part of which is fed into the first drain line 143, and the other part is used as the top reflux liquid. After being pressurized by the reflux pump 1423, it is returned to the top of the distillation column 1412 to participate in the gas-liquid mass transfer cycle in the column. The BDO product is fed into the second drain line 144 from the bottom outlet of the column.

[0033] The second discharge line 144 typically includes a discharge pump, a BDO storage tank, and an external pump connected in sequence. The discharge pump is used to pump BDO product from the outlet at the bottom of the tower into the BDO storage tank for temporary storage, and the external pump is used to input the BDO product from the BDO storage tank into an external pipeline. Optionally, there can be multiple BDO storage tanks connected in parallel.

[0034] In some embodiments, such as Figure 3 As shown, the condensation assembly 142 includes: a condenser 1421, a reflux tank 1422, and a reflux pump 1423 connected in sequence; the condenser 1421 is connected to the distillation column 1412 and is used to condense the gas-phase mixture to form a THF-rich solution and non-condensable gas; the reflux pump 1423 is connected to the distillation column 1412 and the first drain line 143 respectively, and is used to pass part of the THF-rich solution in the reflux tank 1422 into the first drain line 143 and another part of the THF-rich solution into the distillation column 1412.

[0035] In this embodiment, the gaseous mixture separated in the distillation column 1412 is fed into the condenser 1421, where the condenser 1421 condenses the gaseous mixture to condense the THF vapor in the mixture into a THF-rich solution, which is then buffered in the reflux tank 1422. The reflux tank 1422, the first drain line 143, and the distillation column 1412 are connected by a reflux pump 1423. The reflux pump 1423 can pump a portion of the THF-rich solution in the reflux tank 1422 into the first drain line 143 for centralized collection, while the other portion of the THF-rich solution is fed into the distillation column 1412 as the top reflux liquid. It is understood that the reflux tank 1422 is also provided with an exhaust port, which can be used to discharge the non-condensable gases after multiple separations.

[0036] In some embodiments, such as Figure 3 As shown, the maleic anhydride hydrogenation reaction system 1 further includes: a hydrogen circulation pipeline 15, which includes a first burner 151 and a first buffer tank 152, a first compressor 153 and a second buffer tank 154 connected in sequence. The second buffer tank 154 and the first burner 151 are connected to a cold high-efficiency separator 1411. The second buffer tank 154 is used to receive the hydrogen-rich gas separated by the cold high-efficiency separator 1411, the first burner 151 is used to burn the hydrogen-rich gas, and the second buffer tank 154 is connected to the reaction device 13.

[0037] In this embodiment, the first burner 151 is directly connected to the exhaust port of the cold high-efficiency separation tank 1411, and is used to combust a portion of the hydrogen-rich gas in the cold high-efficiency separation tank 1411. The exhaust port of the cold high-efficiency separation tank 1411 is also connected to the first buffer tank 152, so that another portion of the hydrogen-rich gas is introduced into the first buffer tank 152, and then sequentially passes through the first compressor 153 and the second buffer tank 154 to form circulating hydrogen, which is then reintroduced into the reaction apparatus 13 as a reactant. The first buffer tank 152 and the second buffer tank 154 can be used to buffer the hydrogen-rich gas, and the first compressor 153 can be used to compress the hydrogen-rich gas to increase the gas pressure, so that the final high-pressure circulating hydrogen can meet the reaction requirements. It is understood that the bottom of the first buffer tank 152 and the second buffer tank 154 can also be provided with drain ports to discharge the condensate inside the buffer tanks.

[0038] Furthermore, in some implementations, the exhaust port of the second buffer tank 154 is also connected to a third burner 155 so that, if necessary, a portion of the recycled hydrogen can be introduced into the third burner 155 for combustion.

[0039] In some embodiments, such as Figure 2As shown, the hydrogen supply pipeline 12 includes: a second burner 121 and a filter 122, a third buffer tank 123, a second compressor 124 and a fourth buffer tank 125 connected in sequence. The second burner 121 is connected to the filter 122. The filter 122 is used to connect to an external hydrogen supply pipeline to filter external hydrogen and pass the filtered impurities into the second burner 121 and the filtered hydrogen into the third buffer tank 123. The fourth buffer tank 125 is connected to the reaction device 13.

[0040] In this embodiment, the inlet of filter 122 is connected to an external hydrogen supply pipeline to filter received external hydrogen. The filtered impurities are then passed into the second burner 121 for combustion, and the filtered hydrogen is passed into the third buffer tank 123. The hydrogen then passes sequentially through the second compressor 124 and the fourth buffer tank 125 before being introduced into the reaction apparatus 13 as a reactant. The third and fourth buffer tanks 123 and 125 can be used to buffer the hydrogen, and the second compressor 124 can compress the hydrogen to increase its pressure, ensuring that the resulting high-pressure hydrogen meets the reaction requirements. It is understood that a drain port can also be provided at the bottom of the third buffer tank 123 to discharge any condensate inside.

[0041] In some embodiments, such as Figure 2 As shown, the reaction apparatus 13 includes a preheater 131 and a reaction assembly 132 connected in sequence; the preheater 131 is connected to the maleic anhydride supply line 11 and the hydrogen supply line 12 respectively; the reaction assembly 132 is connected to the separation device 14.

[0042] In this embodiment, the preheater 131 is used to receive maleic anhydride in the maleic anhydride supply line 11 and hydrogen in the hydrogen supply line 12, so as to mix and preheat the maleic anhydride and hydrogen, and then pass the mixed and preheated reactants into the reaction assembly 132 for catalytic reaction.

[0043] Specifically, in some embodiments, such as Figure 2 As shown, the preheater 131 has a high-temperature side and a low-temperature side. The inlet of the low-temperature side is connected to the maleic anhydride supply line 11 and the hydrogen supply line 12, respectively, and the outlet of the low-temperature side is connected to the inlet of the reaction assembly 132. The inlet of the high-temperature side is connected to the outlet of the reaction assembly 132, and the outlet of the high-temperature side is connected to the separation device 14.

[0044] In this embodiment, the high-temperature side and the low-temperature side can be two chambers or channels that can exchange heat with each other. The low-temperature side is used to receive maleic anhydride in maleic anhydride supply line 11 and hydrogen in hydrogen supply line 12, and to mix the maleic anhydride and hydrogen at a lower temperature. The high-temperature side is connected to the outlet of the reaction component 132 and is used to receive the reaction products generated by the reaction component 132 at a higher temperature. The residual heat in the reaction products on the high-temperature side can be used to preheat the maleic anhydride-hydrogen mixture on the low-temperature side, thereby reducing the energy consumption of the entire system.

[0045] In some embodiments, such as Figure 2 As shown, the reaction assembly 132 includes: a hydrogenation reactor 1321 and a molten salt circulation pipeline 1322; the hydrogenation reactor 1321 is connected to the preheater 131 and the separation device 14 respectively; the molten salt circulation pipeline 1322 is connected to the hydrogenation reactor 1321 and is used to introduce molten salt into the hydrogenation reactor 1321 to remove the reaction heat in the hydrogenation reactor 1321.

[0046] In this embodiment, the hydrogenation reactor 1321 provides a reaction environment with suitable reaction conditions (including catalyst, reaction temperature, and reaction pressure) for the catalytic reaction of maleic anhydride and hydrogen to obtain reaction products. The hydrogenation reactor 1321 adopts a multi-stage nested structure, with multiple concentric cylindrical reaction zones inside, connected by annular channels. The material enters from the bottom of the innermost reaction zone and reacts layer by layer outwards under the action of the catalyst, increasing the reaction path and residence time, and improving the reaction conversion rate. A spiral heat exchange channel is provided inside the reactor wall, which can communicate with the molten salt circulation pipeline 1322. The molten salt circulation pipeline 1322 can use the molten salt inside as a heat transfer medium to indirectly exchange heat with the material in the reactor, promptly removing the heat generated by the reaction. Combined with the catalyst's adaptability to the reaction temperature, the reaction temperature is precisely controlled within the range of 200℃±2℃, ensuring stable reaction.

[0047] Alternatively, heat transfer oil can be used instead of molten salt as the heat transfer medium.

[0048] Specifically, in some embodiments, such as Figure 2 As shown, the hydrogenation reactor 1321 is equipped with a heat dissipation pipeline; the molten salt circulation pipeline 1322 includes: a molten salt high-level tank 13221, a molten salt circulation pump 13222, and a steam generator 13223; the molten salt high-level tank 13221 is used to store molten salt; the molten salt circulation pump 13222 is connected to the inlet of the heat dissipation pipeline and the outlet of the molten salt high-level tank 13221 respectively, and is used to introduce molten salt into the hydrogenation reactor 1321; the steam generator 13223 is connected to the outlet of the heat dissipation pipeline and the inlet of the molten salt high-level tank 13221 respectively, and is used to introduce external feedwater to dissipate heat from the molten salt, while simultaneously producing low-pressure steam as a byproduct.

[0049] In this embodiment, the heat dissipation pipes, steam generator 13223, molten salt high-level tank 13221, and molten salt circulation pump 13222 in the hydrogenation reactor 1321 are connected end to end to form a circulation loop. The molten salt used for heat transfer can circulate and dissipate heat to cool the material in the reactor in the heat dissipation pipes. The heated molten salt flows into the steam generator 13223, which can be connected to an external water supply pipe to use the heat in the molten salt to heat the water supply and generate low-pressure steam, thereby improving the energy utilization rate of the entire system. The cooled molten salt flows back into the molten salt high-level tank 13221 and is pumped into the heat dissipation pipes by the molten salt circulation pump 13222.

[0050] In some embodiments, such as Figure 2 As shown, the molten salt circulation pipeline 1322 further includes a molten salt replenishment pipeline 13224; the molten salt replenishment pipeline 13224 is connected to the molten salt high-level tank 13221 and is used to supply molten salt to the molten salt high-level tank 13221. The molten salt replenishment pipeline 13224 can be used to supply molten salt from an external pipeline to the molten salt high-level tank 13221 when the amount of molten salt in the molten salt circulation pipeline 1322 is insufficient.

[0051] Specifically, the molten salt replenishment pipeline 13224 may include a replenishment tank and a replenishment pump. The replenishment tank is used to temporarily store molten salt. The replenishment tank is connected to the molten salt high-level tank 13221 through the replenishment pump so that molten salt can be introduced into the molten salt high-level tank 13221.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A maleic anhydride hydrogenation reaction system, characterized in that, include: Maleic anhydride supply line, used to supply maleic anhydride; Hydrogen supply pipeline, used to supply hydrogen gas; The reaction apparatus is connected to the maleic anhydride supply line and the hydrogen supply line, respectively, and is used to catalyze the mixture of maleic anhydride and hydrogen to generate reaction products; A separation device includes a separation component, a condensation component, a first drain line, and a second drain line; the separation component is connected to the reaction device, the condensation component, and the second drain line respectively; the condensation component is connected to the first drain line. The separation component is used to separate the reaction products into a gaseous mixture and a BDO product. The gaseous mixture is passed into the condensation component to obtain a THF-rich solution, and the THF-rich solution is passed into the first drain line, while the BDO product is passed into the second drain line. The condensation component is used to condense the gaseous mixture and pass the condensed THF-rich solution into the first drain line.

2. The maleic anhydride hydrogenation reaction system according to claim 1, characterized in that, The separation component includes: A cold high-efficiency separator, connected to the reaction apparatus, is used to separate the reaction products into hydrogen-rich gas and liquid products; The distillation column is connected to the cold high-efficiency separation tank, the condensation assembly, the first drain line, and the second drain line, respectively. The distillation column is used to separate the liquid phase product into the gas phase mixture and the BDO product.

3. The maleic anhydride hydrogenation reaction system according to claim 2, characterized in that, The condensation assembly includes: a condenser, a reflux tank, and a reflux pump connected in sequence; The condenser is connected to the distillation column and is used to condense the gas-phase mixture to form the THF-rich solution and non-condensable gas. The reflux pump is connected to the distillation column and the first discharge line, respectively, and is used to pass a portion of the THF-rich solution in the reflux tank into the first discharge line, and to pass another portion of the THF-rich solution into the distillation column.

4. The maleic anhydride hydrogenation reaction system according to claim 2, characterized in that, Also includes: The hydrogen circulation pipeline includes a first burner and a first buffer tank, a first compressor, and a second buffer tank connected in sequence. The second buffer tank and the first burner are connected to the cold high-efficiency separator. The second buffer tank is used to receive the hydrogen-rich gas separated by the cold high-efficiency separator. The first burner is used to burn the hydrogen-rich gas. The second buffer tank is connected to the reaction device.

5. The maleic anhydride hydrogenation reaction system according to claim 1, characterized in that, The hydrogen supply pipeline includes a second burner and a filter, a third buffer tank, a second compressor, and a fourth buffer tank connected in sequence. The second burner is connected to the filter. The filter is used to connect to an external hydrogen supply pipeline to filter external hydrogen and pass the filtered impurities into the second burner and the filtered hydrogen into the third buffer tank. The fourth buffer tank is connected to the reaction device.

6. The maleic anhydride hydrogenation reaction system according to claim 1, characterized in that, The reaction apparatus includes a preheater and a reaction assembly connected in sequence; The preheater is connected to the maleic anhydride supply pipeline and the hydrogen supply pipeline, respectively; The reaction assembly and the separation device are connected.

7. The maleic anhydride hydrogenation reaction system according to claim 6, characterized in that, The preheater has a high-temperature side and a low-temperature side. The inlet of the low-temperature side is connected to the maleic anhydride supply pipeline and the hydrogen supply pipeline, respectively, and the outlet of the low-temperature side is connected to the inlet of the reaction component. The inlet of the high-temperature side is connected to the outlet of the reaction component, and the outlet of the high-temperature side is connected to the separation device.

8. The maleic anhydride hydrogenation reaction system according to claim 6, characterized in that, The reaction assembly includes: The hydrogenation reactor is connected to both the preheater and the separation device. A molten salt circulation pipeline, connected to the hydrogenation reactor, is used to introduce molten salt into the hydrogenation reactor to remove the heat of reaction within the reactor.

9. The maleic anhydride hydrogenation reaction system according to claim 8, characterized in that, The hydrogenation reactor is equipped with heat dissipation pipes; The molten salt circulation pipeline includes: Molten salt high-level tank, used for storing molten salt; A molten salt circulation pump is connected to the inlet of the heat dissipation pipeline and the outlet of the molten salt high-level tank, respectively, for feeding the molten salt into the hydrogenation reactor; A steam generator is connected to the outlet of the heat dissipation pipe and the inlet of the molten salt high-level tank, respectively, and is used to introduce external water to dissipate heat from the molten salt.

10. The maleic anhydride hydrogenation reaction system according to claim 9, characterized in that, The molten salt circulation pipeline also includes: A molten salt replenishment pipeline is connected to the molten salt high-level tank and is used to supply molten salt to the molten salt high-level tank.

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