Low water-air ratio and middle water-air ratio carbon monoxide (CO) conversion process

Abstract

The invention relates to a low water-air ratio and middle water-air ratio carbon monoxide (CO) conversion process. The process comprises the following steps of: (1) feeding raw gas into a pre-converter, wherein the temperature of the raw gas entering the inlet of the pre-converter is between 210 and 250 DEG C and the mole ratio of water to dried gas is 0.21 to 0.23; (2) feeding pre-converted mixed gas into a first converter to perform depth conversion, wherein the temperature of the pre-converted mixed gas entering the inlet of the first converter is between 260 and 290 DEG C and the mole ratio of water to dried gas is 0.8 to 1.0; (3) feeding the mixed gas passing through the first converter into a second converter, wherein the temperature of the mixed gas entering the inlet of the secondconverter is between 220 and 250 DEG C and the mole ratio of water to dried gas is 0.5 to 0.7; (4) feeding the mixed gas passing through the second converter into a third converter, wherein the temperature of the secondary conversion mixed gas entering the inlet of the third converter is between 205and 235 DEG C; and performing conversion on the mixed gas by using the third converter to obtain the mixed gas with the CO content lower than 0.40 percent. The process is unique and has the characteristics of high CO conversion rate, low energy consumption in the conversion process and the like.

Description

technical field [0001] The invention relates to a CO conversion process, in particular to a CO conversion process with a water-gas ratio in a string with a low water-gas ratio. Background technique [0002] Since the beginning of the 21st century, due to the impact of increasingly tight oil resources, my country's coal chemical industry has entered a stage of rapid development. Projects such as the production of synthetic ammonia and methanol using coal as raw materials have been launched one after another. The Shell pulverized coal gasification technology is used to produce syngas in terms of requirements, effective components in syngas and operating costs. Since the CO dry basis volume content of the crude synthesis gas produced is as high as 60% or more, and the CO shift reaction is a highly exothermic reaction, how to effectively control the bed temperature of the CO shift reaction, avoid the occurrence of methanation side reactions, and prolong the life of the shift cata...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a CO shift process with a low water-gas ratio string in the water-gas ratio to solve the short service life and rapid deactivation of the pre-shift catalyst in the high water-gas shift process. , frequent replacement, and large pressure drop in the system. At the same time, it solves the problems of small reaction driving force, large number of shift furnaces or reaction stages, low CO conversion rate, and serious hydrogen consumption in the methanation section in the low water-gas ratio shift process.

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