Horizontal multi-flow plate type reactor used for large-scale DMO reaction

Abstract

To provide a horizontal multi-flow plate type reactor that controls uniformity of a floor temperature of each step, can improve a DMO yield and safety of an operation and is used in a large scale DMO reaction.SOLUTION: A reactor is a large scale horizontal multi-flow plate type reactor including a horizontal multi nozzle shell, provided with a plurality of sets of source gas inlets / outlets on the shell and inlets / outlets on a heat transfer side, provided with a catalyst layer (3) in the shell, and is used in a manufacturing method of causing a reaction of methyl nitrite and CO to obtain dimethyl oxalate (DMO), the catalyst layer (3) contains at least two steps of flow, each flow is constituted of a plurality of plate type temperature control modules (2) filled with the catalyst, and heights of the catalysts filled in each plate type temperature control module (2) of the same flow steps are same.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a DMO reaction apparatus, and particularly to a horizontal multi-flow plate type reaction apparatus used for large-scale DMO reactions.

Background Art

[0002] Currently, ethylene glycol projects in China are developing rapidly and mainly focus on producing ethylene glycol by catalytic hydrogenation of dimethyl oxalate in the carbon synthesis pathway. Therefore, dimethyl oxalate is used as the main raw material for ethylene glycol preparation, and its preparation is also a very important research field. When the reaction temperature is lower than the expected temperature, dimethyl oxalate (DMO) will condense on the surface of the catalyst. The condensate may fill the pores of the catalyst and reduce the activity of the catalyst. At the same time, since methyl nitrite (MN), which is a reactant, has self-decomposability, in the reaction apparatus, attention must be paid to controlling the temperature within a certain range to avoid the rapid decomposition reaction of MN under high-temperature conditions. Therefore, for this reaction, it is particularly important to control the temperature distribution of the catalyst layer in the reactor.

[0003] With the increasing demand for ethylene glycol, a downstream product, the production capacity of coal-derived ethylene glycol projects has been expanded accordingly. Considering the manufacturing cost and operating energy consumption, it is essential to scale up the reactors in each process of coal-derived ethylene glycol. Currently, most DMO synthesis reactors are multi-tubular isothermal reactors, and their production capacity mainly ranges from 50,000 to 200,000 tons of DMO / year. There are many limitations to the trend of scaling up the reaction equipment. The first is that with the increase in the diameter of the multi-tubular isothermal reactor, the cost of the tube sheet increases significantly, resulting in a large amount of investment in the construction of the reaction equipment. The second is that due to the low operating pressure of the carbonylation reaction system, the carbonylation gas circulator becomes the main energy-consuming device for coal-derived ethylene glycol. The increase in the height of the multi-tubular isothermal reactor leads to an increase in the pressure drop of the catalyst layer, a significant increase in the operating energy consumption of the gas circulator, and severely limits the scale-up of the reactor. The third is that the increase in the tube diameter of the multi-tubular isothermal reactor leads to non-uniform temperature distribution in the catalyst layer, and over-temperature phenomena are likely to occur at the center of the heat exchange tubes, affecting the operating safety. The fourth is that with the increase in the diameter of the multi-tubular isothermal reactor, the phenomenon of non-uniform flow on the cooling water side increases significantly, worsening the non-uniformity of the catalyst layer temperature. The fifth is that when the diameter of the multi-tubular isothermal reactor exceeds the limit of road transportation and equipment processing and welding must be carried out at the manufacturing site, the manufacturing difficulty of the reactor increases. Therefore, the multi-tubular isothermal reactor cannot meet the design requirements for scaling up the reaction equipment (production capacity of 200,000 to 400,000 tons of DMO / year) and does not conform to the current development trend of "large scale, low energy consumption, high efficiency, and low pollution" in the Chinese chemical industry.

[0004] Most conventional fixed-bed horizontal reactors are adiabatic reactors. Patent Document 1 discloses a horizontal reactor without a heat transfer device in the catalyst layer, which preheats and cools through heat exchangers at the inlet and outlet of the reactor. However, since the DMO reaction has a high heat generation rate and a large amount of heat released, this type of reactor cannot meet the heat exchange requirements of the reaction. Conventional fixed-bed horizontal reactors can reduce pressure drop and investment to varying degrees, but there are still problems such as difficulty in filling and removing the catalyst and non-uniform gas distribution in the reactor. Especially for rapid exothermic reactions, the catalyst layer needs to remove the reaction heat by an efficient heat transfer device, and at the same time, the complex structure inside the reactor needs to be considered, which cannot be satisfied by existing horizontal reactors.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention aims to overcome the above-mentioned problems in the prior art, and an object of the present invention is to provide a horizontal multi-flow plate type reaction device used for large-scale DMO reactions with a high heat transfer coefficient.

[0007] Focusing on various limitations of multitubular isothermal reactors in expanding the production capacity of DMO synthesis devices, the multi-flow plate type reactor of the present invention has a high heat transfer coefficient, a large catalyst filling rate, and can achieve an expansion of production capacity with the same size. The horizontal multi-flow plate type reactor of the present invention has a high heat transfer coefficient, a small required heat exchange area, does not require an expensive tube sheet, and is advantageous for reducing the manufacturing cost of the reactor. The relatively small catalyst layer pressure loss and the system's operating pressure drop are advantageous for reducing the energy consumption of the gas circulator and the operating cost of production. The temperature and flow rate on the water side can be adjusted step by step to control the uniformity of the catalyst layer temperature at each stage, and the DMO yield and operating safety can be improved. The diameter of the reactor is not limited by the catalyst filling amount, meets the requirements of road transportation, facilitates the transportation of the entire reactor, and reduces the manufacturing difficulty. Furthermore, the entire reactor adopts an independent modular design, and the characteristics of the module are determined by the design parameters of the horizontal pair plate. A plurality of sets of horizontal pair plates form independent modules, and a plurality of sets of modules are connected in series and in parallel to be integrated as a large reactor. Compared with the scale-up effect of the multitubular isothermal reactor, the heat transfer performance of each module of this reactor is uniform without deviation, and the risk of industrial scale-up is significantly reduced.

Means for Solving the Problems

[0008] In the present invention, in order to achieve the above object, the following technical means are taken. A horizontal multi-nozzle shell is included, a plurality of sets of raw material gas inlets and outlets and inlets and outlets on the heat transfer side are provided on the shell, and a horizontal multi-flow plate type reactor used for large-scale DMO reaction in which a catalyst layer (3) is provided in the shell, wherein the catalyst layer includes at least two stages of flow, and each flow is composed of a plurality of plate type temperature control modules (2) filled with catalyst, and the height of the catalyst filled in each plate type temperature control module (2) in the same flow stage is the same.

[0009] The flow pattern of the fluid within each stage flow is a co-current flow pattern or a counter-current flow pattern. By connecting multiple sets of the same modules in parallel in the axial direction for each stage flow, the production capacity expansion of the reactor is satisfied, and the limitation of road transportation due to an increase in the diameter of the reactor is avoided.

[0010] Each stage flow connects multiple sets of plate-type temperature control modules (2) in parallel in the axial direction.

[0011] The plate-type temperature control module (2) includes several identical corrugated heat exchange plate pairs (11). A catalyst is filled between adjacent corrugated heat exchange plate pairs (11) on a removable grid provided at the bottom of each corrugated heat exchange plate pair (11). The plate-type temperature control module unit separates several identical corrugated heat exchange plate pairs (11) at a certain distance, welds four thick plates to the outermost corrugated heat exchange plate respectively, seals the perimeter by full circumferential welding, and leaves only the upper and lower openings for the flow of fluid.

[0012] According to the characteristics of the carbonylation reaction, the corrugated heat exchange plate pair (11) is a horizontal corrugated heat exchange plate pair (11), and the distance between adjacent corrugated heat exchange plate pairs is in the range of 10 mm to 100 mm.

[0013] The horizontal multi-nozzle shell includes a cylindrical body (5) with a diameter of 3 to 6 meters and a length of 8 meters or more. Manhole covers (4) and multiple sets of raw material gas inlets and outlets and heat transfer side inlets and outlets are provided at both ends. The number or cross-sectional area of the heat transfer side inlets and outlets is at least twice the number or cross-sectional area of the raw material gas inlets and outlets. At least one steam drum is connected to each heat transfer side inlet, and an emergency vent valve is arranged at each branch on the heat transfer side.

[0014] At least two equally spaced and parallel raw material gas inlets a(6) are arranged horizontally on one side of the horizontal multi-nozzle shell, and corresponding product outlets a(7) are arranged on the opposite side. The raw material gas can flow in from the raw material gas inlet a(6) at the upper right of the reactor, pass through a U-shaped flow, and then flow out from the product outlet a(7) at the upper left of the reactor. Alternatively, at least two equally spaced and parallel raw material gas inlets b(8) are arranged horizontally above the horizontal multi-nozzle shell, and corresponding product outlets b(9) are arranged at the bottom. The raw material gas can flow in from the raw material gas inlet b(8) on the upper side of the reactor and flow out from the product outlet b(9) on the lower side of the reactor via at least two different catalyst layers in at least two stages.

[0015] At least one vertical baffle (12) arranged axially in the horizontal multi-nozzle shell divides the reactor into at least two left and right flows in the radial direction. The upper side of the vertical baffle (12) for partitioning the flow is a baffle without perforations, and the lower side is a perforated plate uniformly perforated. The ratio of the baffle without perforations to the perforated plate is 10 - 2:1, and the perforation rate of the perforated plate is in the range of 15% - 65%, and it can also be 100%.

[0016] The horizontal baffle (13) for gas dispersion arranged radially in the horizontal multi-nozzle shell divides the reactor into at least two upper and lower flows in the axial direction. The horizontal baffle (13) for gas dispersion is uniformly perforated, and the perforation rate is in the range of 30% - 70%, and it can also be 100%.

[0017] The catalyst layer is composed of at least two-stage flow, and the two-stage or more flow is composed of at least two sets of different plate-type temperature control modules. Each parameter of the set of plate-type temperature control modules within the same-stage flow is consistent, and the heights of catalyst filling are all the same. Near the raw material gas inlet, the interval D1 between the pair of plates of the plate-type temperature control module (2) in the same flow stage ranges from 10 mm to 60 mm, more preferably from 15 mm to 45 mm, and the height h1 of catalyst filling ranges from 1.5 m to 4.3 m. Near the raw material gas outlet, the interval D2 between the pair of plates of the plate-type temperature control module (2) in the same flow stage ranges from 20 mm to 100 mm, more preferably from 20 mm to 60 mm, and the height h2 of catalyst filling ranges from 0.3 m to 4.0 m. Here, D1 < D2 and h1 > h2.

[0018] The DMO synthesis reaction is a highly exothermic reaction. Since methyl nitrite (MN), which is a reactant thereof, undergoes a rapid decomposition reaction under high-temperature conditions, the reaction temperature rises rapidly, resulting in an explosion phenomenon due to a thermal runaway reaction, which significantly affects the safety of production. The DMO reaction rate depends on the temperature and the concentration of the reactants. The concentration of the reactants is high at the inlet of the reactor, and the reactivity is good. The concentration of the reactants is lower and the reactivity decreases towards the outlet side of the reactor. Therefore, the reaction amount in the first half of the catalyst layer is high, and a higher heat removal capacity is required compared to the second half of the catalyst layer. Therefore, in the first half of the catalyst layer, it is necessary to suppress the decomposition of MN and increase the yield under the condition of ensuring high heat conduction efficiency. At the same time, the boiling point of the product DMO is higher than that of other components. When the temperature of the reactor is lower than its lower limit, condensation of DMO occurs on the surface of the catalyst, and the condensate penetrates into the pores of the catalyst, which may reduce the activity of the catalyst. Therefore, precise control of the reaction temperature is particularly important throughout the reaction process. The entire reaction process is preferably carried out at a temperature in the range of 50 to 200 °C, more preferably in the range of 80 to 150 °C. The reaction pressure is preferably above atmospheric pressure, but below 10 kg / cm 2 G (about 1 MPaG), more preferably below 5 kg / cm 2It is below G (about 0.5 MPaG). Furthermore, according to the characteristics of this reaction, in the first half of the catalyst layer, it is necessary to control the temperature within a certain range in order to enhance the heat transfer capacity of the reactor and avoid the rapid decomposition reaction of MN under high-temperature conditions. In the second half of the catalyst layer, it is necessary to weaken the heat transfer capacity of the reactor and control the reaction outlet temperature to 80 °C or higher.

[0019] Therefore, considering the reaction results and safety, the temperature distribution of the catalyst layer in the reactor must be strictly controlled. Thus, a multi-stage multi-flow reactor is invented, which incorporates plate-type temperature control modules with different heat exchange capabilities and forms a multi-flow internal structure through a parallel and series connection configuration to control the reaction temperature in multiple stages. In the first half of the catalyst layer of the DMO synthesis reaction, since the heat generation is intense, a high heat exchange capacity is required. Regarding the characteristic of controlling the temperature uniformity in the second half of the catalyst layer to increase the yield, at least two flows with different plate intervals are designed. The plate interval of the previous-stage flow is relatively small to enhance the heat exchange capacity, and the plate interval of the subsequent-stage flow is relatively large to control the reaction temperature to be stable and prevent the outlet temperature from becoming too low.

[0020] Also, as the production capacity of the coal-derived ethylene glycol project gradually expands, in the DMO synthesis reaction, it is required to reduce the resistance of the catalyst layer as much as possible, decrease the pressure drop of the catalyst layer, reduce the power of the circulating gas compressor, and save the operating energy consumption. The height of the catalyst layer in the horizontal reactor is low. Through the combination of the plate-type modular design, a low pressure drop can still be ensured when expanding the production capacity, and the filling of the catalyst is simpler and more uniform. The contact time between the feed gas and the catalyst in each channel is controlled to be 0.2 to 10 seconds to ensure the safety of the reaction and achieve energy conservation and emission reduction.

[0021] The horizontal multi-stage temperature control plate-type reactor is formed by connecting multiple unit modules and cooperates with multiple sets of heat transfer side inlets and outlets and emergency vent valves to individually adjust the steam drums (temperature and flow rate) of each unit module. The temperature control of the catalyst layer is more convenient and thus more helpful for realizing safe and stable production.

Advantages of the Invention

[0022] Compared with the prior art, the present invention has the following advantages. 1. The internal temperature control plate unit of the horizontal multi-stage temperature control plate type reactor is composed of a modular structure. By arranging multiple sets of modules in parallel in the axial direction according to the production capacity requirements, the diameter of the reactor can be increased without exceeding the limitation range of road transportation. Therefore, each component of the horizontal reactor can be processed and assembled in the factory, without the requirement of tube sheet manufacturing, which not only improves the manufacturing accuracy but also reduces the manufacturing cost.

[0023] 2. The height of the catalyst layer of the horizontal multi-stage temperature control plate type reactor is not affected by the expansion of production capacity. For example, when controlling the production capacity of 200,000 tons / year of DMO under the operating conditions of a certain space velocity, the pressure drop of the catalyst layer of the horizontal reactor is only 25 kPa, which is much lower than 170 kPa of the multi-tubular reactor. Even when the space velocity increases, the pressure drop of the horizontal reactor is only 35 kPa, and the total height of the catalyst layer of its multi-stage flow does not exceed 5 m, and the pressure drop of the catalyst layer is significantly reduced and can be controlled within the range of 15 kPa to 50 kPa. Therefore, the horizontal reactor can significantly reduce the pressure drop of the system operation and reduce the power of the compressor, thereby saving the operation cost.

[0024] 3. The multi-flow and modular design of the horizontal multi-stage temperature control plate type reactor helps to individually adjust the cooling water flow rate and temperature of each flow and module, significantly improving the convenience and accuracy of the temperature control of the catalyst layer. At the same time, through the control of the multi-stage flow, the overall reaction temperature becomes uniform, there is no obvious hot spot part, which is helpful for adjusting the catalyst layer temperature, avoiding thermal runaway and increasing the DMO yield.

[0025] 4. The horizontal multi-stage temperature control plate-type reactor has excellent thermal conductivity, uniform flow distribution on the cooling water side, convenient and uniform catalyst filling, and a modular design, which can make the temperature distribution of the catalyst layer in each channel uniform and there is no local high-temperature part. Therefore, the horizontal multi-stage temperature control plate-type reactor is more helpful for increasing the DMO yield and has better production safety and stability.

[0026] 5. The device of the present invention has characteristics such as "stable, energy-saving, safe, and high-efficiency", and by conforming to the current scale-up development trend of chemical engineering production, it is one of the reactors with the most potential in the field of coal-derived ethylene glycol.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0028] Hereinafter, the present invention will be described in detail with reference to specific examples. The following examples help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be pointed out that those skilled in the art can make various changes and modifications without departing from the technical idea of the present invention.

[0029] The horizontal multi-flow temperature control plate-type reactor of the present invention can arrange the reactor in various forms according to needs.

[0030] The First Form Referring to FIGS. 1 and 2, the horizontal multi-flow temperature control plate type reactor used in the large-scale carbonylation reaction in the production method of obtaining dimethyl oxalate (DMO) by reacting methyl nitrite with CO includes a horizontal multi-nozzle shell. The shell is a horizontally placed horizontal shell, with end plates 4 provided at both ends, including a cylindrical body 5, and the shell diameter is 3 to 4.5 meters. The inside of the shell includes at least two or more multi-stages of flows with different heat exchange capabilities. At least two equally spaced and parallel raw material gas inlets a6 are arranged in the horizontal direction on the right side of the cylindrical body, and a corresponding product outlet a7 is arranged on its left side. At least one vertical baffle 12 that partitions the flow arranged in the axial direction in the shell divides the reactor into at least two left and right flows (the upper side of the vertical baffle (12) that partitions the flow is a baffle without perforations, and the lower side is a perforated plate uniformly perforated. The ratio of the baffle without perforations to the perforated plate is 10 to 2:1, and the perforation rate of the perforated plate ranges from 15% to 65%, and it can also be 100%). The carbon monoxide and methyl nitrite of the raw material gas flow into the right platinum group metal catalyst layer from the raw material gas inlet a6 at the upper right of the reactor to react, and then enter the catalyst layer on the left through the vertical baffle 12 that partitions the flow, forming a U-shaped flow, and further flowing out from the product outlet a7 at the upper left of the reactor to obtain the product. The right flow contains 2 to 20 plate type temperature control modules 2 connected in parallel. Each plate type temperature control module 2 arranges several same heat exchange corrugated pair plates 11 at a distance of 15 mm to 45 mm. The left flow contains 2 to 20 plate type temperature control modules 2, and the heat exchange corrugated pair plates 11 therein are arranged at a distance of 20 mm to 80 mm. The catalyst is filled between the heat exchange corrugated pair plates. Circulating water inlets and outlets are provided on the heat exchange corrugated pair plates 11, and the heat quantity is removed by the circulating water inside the pair plates. The reaction raw material gas reacts on the catalyst of the pair plates. The circulating water inlets and outlets are the inlets and outlets on the heat transfer side (the heat transfer side inlet 10 and the heat transfer side outlet 10' in FIG. 2). The circulating water inlets and outlets are connected to at least one steam drum, and emergency vent valves are arranged on each branch on the heat transfer side to adjust the reaction temperature and ensure that the reaction proceeds safely.

[0031] The second form Referring to FIGS. 1 and 3, another horizontal multi-flow temperature control plate type reactor used in large-scale carbonylation reaction includes a horizontal multi-nozzle shell, the shell being a horizontally placed horizontal shell, with end plates 4 provided at both ends, including a cylindrical body 5, and the shell diameter being 4 to 6 meters. The interior of the shell includes at least two or more stages of multi-flows with different heat exchange capabilities. At least two equally spaced and parallel raw material gas inlets 8 are arranged in the horizontal direction above the cylindrical body, and a product outlet 9 corresponding to its bottom is arranged. The horizontal baffle 13 for gas dispersion arranged in the radial direction within the reactor shell divides the reactor into at least two upper and lower flows in the axial direction (the horizontal baffle 13 for gas dispersion is uniformly perforated, and the perforation rate is in the range of 30% to 70%, and can also be in the range of 100). Carbon monoxide and methyl nitrite of the raw material gas flow into the platinum group metal catalyst layer from the inlet 8 above the reactor to cause a reaction, then enter the lower catalyst layer via the horizontal baffle 13 for gas dispersion, and finally flow out from the product outlet 9. The upper flow includes 2 to 20 plate type temperature control modules 2, and each plate type temperature control module 2 arranges several same corrugated pair plates 11 for heat exchange at a distance of 10 mm to 40 mm. The lower flow includes 2 to 20 plate type temperature control modules 2, and the corrugated pair plates 11 for heat exchange are arranged at a distance of 15 mm to 60 mm. The catalyst is filled between the corrugated pair plates for heat exchange, and the heat quantity is removed by the circulating water inside the corrugated pair plates for heat exchange. The circulating water inlet and outlet are the inlet and outlet on the heat transfer side (the heat transfer side inlet 10 and the heat transfer side outlet 10' in FIG. 3), which are connected to at least one steam drum, and emergency vent valves are arranged on each branch of the heat transfer side to adjust the reaction temperature and ensure that the reaction can proceed safely.

[0032] By changing the order of the circulating water inlets and outlets (10, 10'), the flow can be controlled in a co-current or counter-current manner. Here, the catalyst filling height of each stage flow is the same, and each stage flow arranges a plurality of sets of the same modules in parallel in the axial direction to meet the expansion of the production capacity of the reactor and avoid the limitation of road transportation due to the increase in the diameter of the reactor.

Example

[0033] In the large-scale alkyl nitrite carbonylation reaction, a horizontal multi-flow type temperature control plate type reactor of the first form is used, and the inner diameter of the reactor is 4 m. Above the reactor, a mixed gas (containing carbon monoxide with a volume concentration of 1 to 35%, methyl nitrite with a volume concentration of 3 to 15%, and at the same time a non-reactive gas such as nitrogen or carbon dioxide gas, a small amount of nitric oxide and alkyl alcohol vapor) after mixing CO and the gas from the regeneration tower (methyl nitrite) by a gas compressor (not shown) is transported to a preheater (not shown), heated and then supplied to the catalyst layer. The overall reaction temperature is controlled to 80 to 150 °C through the temperature control plate of the reactor, and carbon monoxide and methyl nitrite are reacted. The total height of the two-stage flow catalyst layer of the horizontal reactor is 4.5 m, the catalyst is uniformly filled, the operation of the reactor is stable, and compared with a multi-tubular reactor under the same operating conditions, the pressure drop of the catalyst layer is smaller, only 45 kPa, the heat transfer effect is remarkable, the heat transfer coefficient of the horizontal multi-flow type temperature control plate type reactor is 1.5 to 2 times that of the multi-tubular reactor, and under the same hot spot temperature conditions, the DMO yield is improved by about 15 to 20%.

Example

[0034] In the large-scale alkyl nitrite carbonylation reaction, under the same reaction conditions as in Example 1, a horizontal multi-flow type temperature control plate type reactor of the second form is used, the inner diameter of the reactor is 4.8 m, the overall reaction temperature is controlled in the range of 80 to 150 °C for reaction, the total height of the two-stage flow catalyst layer of the horizontal reactor is 2.5 m, the operation of the reactor is stable, and compared with a multi-tubular reactor under the same operating conditions, the pressure drop of the catalyst layer is significantly reduced, only 25 kPa, the power consumption of the circulation compressor is greatly saved, and the operating energy consumption of the system is reduced. The heat transfer effect is remarkable, the temperature distribution of the catalyst layer is uniform, and under the same hot spot temperature conditions, compared with a multi-tubular reactor, the DMO yield is improved by 5 to 10%.

[0035] The reactors in the above examples are used for large-scale DMO reactions, and their performances are shown in the following table.

Table 1

[0036] The DMO yield means the amount of the crude DMO product generated per cubic meter per hour. Here, based on the comparison result with a normal tubular reactor, the heat transfer coefficient and the DMO yield are relative values.

[0037] As can be seen from the above table, the heat transfer effect of the reactor described in Example 1 is remarkable. The heat transfer coefficient is 1.5 to 2 times that of the multi-tubular reactor, and the DMO yield is improved by about 15 to 20%. The heat transfer effect of the reactor in Example 2 is remarkable. The heat transfer coefficient is 1.5 to 2 times that of the multi-tubular reactor, and the DMO yield is improved by about 5 to 10%.

[0038] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical means of the present invention, and the present invention is not limited thereby. It is obvious to those skilled in the art that various substitutions, modifications and changes are possible without departing from the technical idea of the present invention, and when substituted, modified and changed by those skilled in the art, they are also included in the scope defined by the claims of the present invention.

Claims

1. A horizontal multi-nozzle shell is included, and a plurality of sets of raw material gas inlets and outlets and heat transfer side inlets and outlets are provided on the shell. A catalyst layer (3) is provided in the shell, and it is a large horizontal multi-flow plate type reactor used in the production method of causing a reaction between methyl nitrite and CO to obtain dimethyl oxalate (DMO). The catalyst layer includes at least two stages of flow, and each flow is composed of a plurality of plate type temperature control modules (2) filled with catalyst. The height of the catalyst filled in each of the plate type temperature control modules (2) in the same flow stage is the same. A horizontal multi-flow plate type reactor used in large-scale DMO reaction, characterized in that.

2. The flow mode of the fluid in each stage of flow is a co-current mode or a counter-current mode. The horizontal multi-flow plate type reactor used in the large-scale DMO reaction according to claim 1, characterized in that.

3. Each stage of flow is characterized by connecting a plurality of sets of the plate type temperature control modules (2) in parallel in the axial direction. The horizontal multi-flow plate type reactor used in the large-scale DMO reaction according to claim 1.

4. The plate type temperature control module (2) includes several same heat exchange corrugated pair plates (11), and catalyst is filled between the adjacent heat exchange corrugated pair plates (11) on a removable grid provided at the bottom of each heat exchange corrugated pair plate (11). The horizontal multi-flow plate type reactor used in the large-scale DMO reaction according to claim 1, characterized in that.

5. The heat exchange corrugated pair plate (11) is a horizontal heat exchange pair plate, and the distance between the adjacent heat exchange corrugated pair plates (11) is in the range of 10 mm to 100 mm. The horizontal multi-flow plate type reactor used in the large-scale DMO reaction according to claim 4, characterized in that.

6. The horizontal multi-nozzle shell includes a cylindrical body (5), and end plates (4) and a plurality of sets of raw material gas inlets and outlets and heat transfer side inlets and outlets are provided at both ends. The number or cross-sectional area of the heat transfer side inlets and outlets is at least twice the number or cross-sectional area of the raw material gas inlets and outlets, and at least one steam drum is connected to each of the heat transfer side inlets and outlets. The horizontal multi-flow plate type reactor used in the large-scale DMO reaction according to claim 1, characterized in that.

7. At least two equidistant and parallel raw material gas inlets a (6) are arranged horizontally on one side of the horizontal multi-nozzle shell, and corresponding product outlets a (7) are arranged on the opposite side. Alternatively, at least two equidistant and parallel raw material gas inlets b (8) are arranged horizontally above the horizontal multi-nozzle shell, and corresponding product outlets b (9) are arranged at the bottom thereof. The horizontal multi-flow plate type reactor for large-scale DMO reaction according to claim 6, characterized in that.

8. At least one vertical baffle (12) arranged axially in the horizontal multi-nozzle shell divides the reactor into at least two left and right flows in the radial direction. The upper side of the vertical baffle (12) that divides the flow is a baffle without perforations, and the lower side is a perforated plate uniformly perforated. The ratio of the baffle without perforations to the perforated plate is 10 to 2:1, and the perforation rate of the perforated plate ranges from 15% to 65%, and can also be 100%. The horizontal multi-flow plate type reactor for large-scale DMO reaction according to claim 1, characterized in that.

9. The horizontal baffle (13) for gas dispersion arranged radially in the horizontal multi-nozzle shell divides the reactor into at least two upper and lower flows in the axial direction. The horizontal baffle (13) for gas dispersion is uniformly perforated, and the perforation rate ranges from 30% to 70%, and can also be 100%. The horizontal multi-flow plate type reactor for large-scale DMO reaction according to claim 1, characterized in that.

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