CO shift process matched with synthesis of methanol

Abstract

The invention relates to a CO shift process matched with synthesis of methanol. The CO shift process is characterized by comprising the following steps: raw gas firstly enters a low-pressure steam generator for cooling and is subjected to liquid separation to adjust water-gas ratio; the raw gas subjected to liquid separation is divided into two paths, wherein one path accounts for 45 to 55 percentto serve as non-transforming gas, and the rest is used as a second path, is subjected to temperature improvement and detoxification in sequence, is divided again and then enters a gas-cooled converter and an isothermal transformation furnace which are arranged in parallel for isothermal transformation respectively; heat is recovered, subsequently the transformed gas is mixed with the first path of non-transforming gas to serve as synthesis gas; the mole ratio of H2 to CO in the synthesis gas is controlled at 2.1 to 2.3. According to the CO shift process disclosed by the invention, byproductsof medium pressure saturated steam and low pressure overheat stream are generated; the gas-cooled converter uses the transforming gas as a refrigerant; by multiple times of dividing conversions, the CO shift process has the advantages of short flow, small size of the converter, no over-temperature risk, adjustable heat exchange area of the used isothermal transformation furnace, small pressure fluctuation of the byproduct medium pressure steam and more stable system operation.

Description

technical field [0001] The invention relates to the technical field of carbon monoxide conversion, and specifically refers to a CO conversion process supporting methanol synthesis. Background technique [0002] Since the beginning of the 21st century, my country's chemical industry using coal as raw material has developed rapidly. Starting from the shell pulverized coal gasification process introduced in the Netherlands, a variety of independent coal gasification processes have been developed. CO in the raw gas produced by such processes The dry basis content is generally high, reaching more than 60%. For the production equipment that adopts the gasification process to produce syngas and downstream C1 chemical products, it is generally necessary to remove CO in the raw material gas through a shift reaction, which consumes water vapor to produce H2, while changing CO into CO2 which is easy to remove. Downstream products include hydrogen production, synthetic ammonia, methanol ...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is to provide a CO shift process for methanol synthesis in view of the current state of the art, which can effectively solve the problem of overheating of traditional adiabatic shift furnaces and medium-pressure steam systems of isothermal shift furnaces after the catalyst is raised in the middle and late stages. Variable area isothermal transformation process with large pressure fluctuation

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