High-concentration carbon monoxide controllable semi-isothermy conversion process for carbonyl synthesis

Abstract

The invention relates to a high-concentration carbon monoxide controllable semi-isothermy conversion process for carbonyl synthesis. The application range is wide, and raw materials with the volume content of a carbon monoxide dry basis being 30-90% and with the volume ratio of water/extra-dry gas being 0.1-1.6 are adopted; the technological process is short, the number of equipment is small, control is easy, and the investment and operation costs are low; by arranging a controllable semi-isothermy saturated steam generation system with a control valve, the temperature of shift gas can be quickly and effectively adjusted, the steam generating pressure is not affected, the problems that a gas conversion reaction of the raw materials with the high carbon monoxide content is prone to overtemperature and difficult temperature control are solved, the grade of byproduct saturated steam is increased to the largest extent, and the yield of low-pressure saturated steam with low utilization value is decreased; high-pressure saturated steam can be overheated, arranging of an external overheating furnace or heat combination with other devices is not needed, and thus the investment and operation difficulty is lowered; and as for the working condition that the temperature needs to be increased at the terminal stage of a catalyst, only the opening degree of the control valve needs to be appropriately adjusted, and thus operation is convenient.

Description

technical field [0001] The invention relates to a high-concentration carbon monoxide controllable semi-isothermal transformation process for oxo synthesis. Background technique [0002] The carbon monoxide conversion device has an extremely important position in the new coal chemical plant. It is the crude synthesis gas from the upstream gasification device, under the action of the catalyst, and according to the requirements of the downstream product for the hydrogen-carbon ratio, all or part of it reacts to generate hydrogen. . Different product requirements have a greater impact on the settings of the transformation process. For the production of hydrogen and synthetic ammonia, it is usually necessary to convert carbon monoxide into hydrogen as much as possible; for the production of oxo gas, such as synthetic methanol, ethylene glycol, synthetic oil, natural gas, etc., the transformation reaction depth is relatively shallow, and it needs to be converted according to the ...

AI Technical Summary

Problems solved by technology

[0007] However, the currently applied isothermal shift technology, including the high-concentration carbon monoxide-to-methanol isothermal process, has the following problems: ① The by-produced steam from the steam drum of the isothermal shift furnace is saturated steam, which cannot produce higher-quality superheated steam

The conversion device is a steam surplus device. Usually, the excess steam is used by other users in the whole plant through the steam pipe network, and the temperature of the saturated steam is lowered to produce condensate, which cannot enter the pipe network.

The outlet temperature of the traditional adiabatic shift furnace is relatively high, usually above 400°C, which can be superheated for saturated steam, while the isothermal shift furnace is mostly taken away by the water circulation system due to the reaction heat, and the outlet temperature is only about 300°C, which cannot provide a superheat source. The heating furnace can be set separately or combined with other devices, which increases the complexity of the process and equipment investment

②It is difficult to adjust the temperature of the isothermal transformation furnace

Since the water circulation between the steam drum and the heat exchange tube is a natural circulation, that is, the water vapor circulation formed by the driving force generated by the static pressure head of water and the density difference of the two-phase flow in the heat exchange tube, so in the control of removing the heat of reaction with a certain degree of difficulty

The invention patent with the application number CN201610194370.2 "A device for adjusting the temperature of the catalyst bed in an isothermal reactor" proposes a method of controlling the temperature of the catalyst bed by adding a regulating valve to the outlet line of the saturated steam to control the steam pressure of the steam drum, but This adjustment method is greatly affected by the pressure fluctuation of the steam pipe network, and the temperature of the saturated water must be adjusted by changing the pressure of the steam drum first, which has a certain hysteresis

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