Novel carbonylation reactor for process of producing glycol through synthesis gas

Abstract

The invention relates to a novel carbonylation reactor for a process of producing glycol through synthesis gas. The reactor is a radial reactor and comprises a reactor shell, a heat exchange component, a flow dividing pipe, a flow collecting pipe and catalyst, wherein the flow dividing pipe is located in the center of the reactor; the heat exchange component is arranged between the flow dividing pipe and the flow collecting pipe; the heat exchange component is arranged in a catalyst bed layer, and the reactor shell comprises a cylinder, an upper seal head, a lower seal head, a reaction gas inlet, a reaction gas outlet, a cooling medium inlet, a cooling medium outlet, a catalyst unloading port and the like; the reaction gas inlet and the reaction gas outlet are arranged on the upper seal head; reaction gas enters the reactor from the reaction gas inlet, then flows downwards along the flow dividing pipe in the center, radially passes through the catalyst bed layer for reaction, and reaction product gas enters the flow collecting pipe, flows upwards along the flow collecting pipe and flows out from the reaction gas outlet. Compared with the prior art, the novel carbonylation reactor for the process of producing glycol through synthesis gas has the advantages of high heat exchange efficiency, small equipment size, high catalyst using efficiency and convenience in loading and unloading.

Description

technical field [0001] The invention relates to a carbonylation reactor, in particular to a novel carbonylation reactor used in the process of producing ethylene glycol from synthesis gas. Background technique [0002] At present, the process of producing ethylene glycol from syngas through dimethyl oxalate has a strong advantage in all ethylene glycol production processes, and carbonylation reaction is one of the key technologies of this process. The carbonylation reaction is divided into two steps, the first is O 2 , NO, esterification reaction with methanol to synthesize the intermediate product methyl nitrite, the reaction conditions are mild and no catalyst is needed; the second step is the carbonylation coupling reaction of CO and methyl nitrite to synthesize the intermediate product dimethyl oxalate , the reaction process uses Pd / Al 2 o 3 catalyst, the reaction temperature is 110-150° C., and the reaction pressure is 1-5 atm. The so-called carbonylation reactor us...

AI Technical Summary

Problems solved by technology

Therefore, it is necessary for the internal heat transfer components of the reactor to have high heat transfer efficiency and a large heat transfer area; the operating pressure is small, which means that the pressure drop cannot be too large, otherwise the compressor pressure ratio will increase, the compressor shaft power will increase, and the energy consumption will increase.

[0003] The tube-and-tube axial carbonylation reactor has the following bottlenecks in increasing the processing capacity of a single unit: in the tube-and-tube reactor, the catalyst is often packed in the tube, and the heat transfer coefficient of the smooth tube is small due to the small temperature range of the catalyst. small, the diameter of the tube is limited, and due to the requirements of the tube center distance, etc., the catalyst filling factor in the reactor is small. If the processing capacity of a single unit is to be increased, the volume of the reactor will increase greatly; because the carbonylation reaction has strict requirements on pressure drop, Therefore, the length of the tubes, i.e., the height of the reactor, is limited to a certain extent. At the same time, from the perspective of transportation, the diameter of the reactor should not be too large, so it is difficult to realize the large-scale equipment of the tube-type carbonylation reactor.

[0004] Chinese patent 201210407063.X discloses an industrial plate reactor for carbonylation coupling synthesis of esters, the reactor is a radial reactor, and the heat exchange device of the reactor is a prefabricated group of heat exchange plates and cooling tube, which can overcome the disadvantages of large pressure drop in a single tubular reactor and the need for a large number of units for large-scale production.

However, the reactor has the following disadvantages: the side of the heat exchange plate in the reactor in contact with the catalyst is a parallel plate-fin structure, the plate-fin spacing is 0.1-0.5 mm, and the catalyst particle size is described in the document as 3.2-5.5 mm. ×3.2~5.5mm, it is obvious that the catalyst cannot be packed between the plate fins, and the reaction gas easily passes through the plate fins, causing a short circuit of the reaction gas, and the plate fin structure not only does not enhance heat transfer, but increases the overall thermal resistance of the metal plate , the heat of the catalyst bed is less likely to be quickly transferred to the cooling medium side; the reaction gas in the reactor flows down the annular gap between the inner wall of the reactor shell and the outer distribution cylinder, and enters the catalyst bed through the outer distribution cylinder of the radial reaction bed The carbonylation reaction is a rapid reaction, and a large amount of heat is released in the initial stage of the reaction. Even though a cold pipe is added between the two plates on the periphery of the fan in this patent, the heat transfer of the cold pipe is poor, and the heat is easy to accumulate, and the cold pipe occupies the reaction area. There is more space in the reactor, which increases the volume of the equipment; the gas flow pattern on the reaction side of the reactor is Z-type, and the Z-type is easy to cause uneven pressure drop distribution of the shunt pipe (19) and the header pipe (21), thereby causing the gas to flow in the The distribution of the catalyst bed is uneven, which affects the use efficiency of the catalyst and the conversion rate of the reaction and other parameters; there are many equipment structures, the leak detection and maintenance work is complicated, and the loading and unloading of the catalyst is inconvenient

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