Method for preparing synthesis gas from coke oven gas and coal-to-gas

Abstract

The invention provides a method for preparing synthesis gas through coke oven gas and coal gas. The coke oven gas and the coal gas are fed to a gas holder to be fully mixed, mixed gas is obtained, methane reforming is conducted on one part of the mixed gas, reformed gas and the other part of mixed gas converge, and are compressed and then purified, H2S, remaining CO2 and other impurities are removed, removed hydrogen sulfide is desulphurized and recovered, removed CO2 is emptied, methane separation is conducted on purified coarse feed gas, liquefied natural gas products or compressed natural gas products are prepared through separated methane gas, and the pure synthesis gas meeting the requirement of the hydrogen-carbon ratio of synthesis downstream products is prepared through gas in which methane is separated. The method has the advantage that the coal gas and the coke oven gas are comprehensively utilized.

Description

technical field [0001] The invention belongs to a method for preparing synthesis gas by using coke oven gas and coal gas. Background technique [0002] Synthesis gas is a kind of raw material gas with carbon monoxide and hydrogen as the main components, which is used as a chemical raw material. Syngas is widely used and is the most basic raw material for synthetic ammonia, natural gas, methanol, ethylene glycol, light olefins, synthetic oil and other products. Syngas has a wide range of raw materials. It is produced by the gasification of carbonaceous minerals such as solid fuels such as coal and charcoal. It can also be produced from light hydrocarbons such as natural gas and naphtha. It can also be produced from heavy oil through partial oxidation. [0003] The composition (volume%) of syngas produced by various methods is very different: H 2 : 32~67, CO: 10~57, CO 2 : 2~28, CH 4 : 0.1~14,N 2 : 0.6-23. In addition, there is a small amount of H 2 S, COS, HCN and othe...

AI Technical Summary

Problems solved by technology

At present, in addition to the production of synthetic ammonia and methanol, coke oven gas has a surplus of nearly 30 billion cubic meters of coke oven gas per year. Due to the characteristics of "more hydrogen and less carbon" in the composition of coke oven gas, the energy utilization rate of coke oven gas at this stage is about 55%. , resulting in huge waste of energy and environmental pollution

[0005] From the characteristics of coke oven gas and coal-to-gas, it can be seen that the production of synthetic ammonia, natural gas, methanol, ethylene glycol, low-carbon olefins, synthetic oil and other products from coke oven gas or coal-to-gas alone has unbalanced component ratios and utilization Insufficient problem: Coke oven gas has more hydrogen and less carbon, and if it is used alone for synthetic products, there will inevitably be a large amount of hydrogen surplus, or additional carbon sources need to be added; while coal-based gas has more carbon and less hydrogen, and if it is used alone, there will be a large amount of carbon surplus, or Requires an additional large amount of supplemental hydrogen source

[0006] At present, in actual production, for the characteristics of coal-based gas with more carbon and less hydrogen, a reasonable hydrogen-carbon ratio is generally obtained through water vapor shift; coke oven gas has more hydrogen and less carbon, and high methane content, and methane carbon dioxide reforming is usually used However, whether it is water-steam shift or methane reforming, there are problems such as high investment, high energy consumption, and complicated operation.

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