Method for producing hydrogen by converting membrane separation impermeable gas obtained after membrane separation of oil wash dry gas used in coal liquefaction project

Abstract

The invention discloses a novel technology for producing hydrogen by converting membrane separation impermeable gas obtained after membrane separation of oil wash dry gas used in a coal liquefaction project, and aims to well solve the problem that black smoke is generated in a pure oxygen conversion process as the membrane separation impermeable gas obtained after membrane separation of the oil wash dry gas is high in higher hydrocarbon content and unsaturated hydrocarbon content. The technology adopts a method conducting CO conversion on feed gas, so as to ensure that the hydrogen content of gas in a raw material outlet is improved effectively, and the spontaneous combustion reliability of the feed gas in a conversion furnace is improved effectively. The concentration of CO in the feed gas entering a heating furnace is reduced due to CO conversion, so that the metal pulverization risk of a furnace tube of the heating furnace is reduced, and requirements on the material of a heating coil are lowered.

Description

technical field [0001] The invention belongs to the field of coal-to-oil production, and in particular relates to a method for producing hydrogen by converting membrane-separated non-permeable gas after membrane-separated oil-washed dry gas in a coal-to-oil project. Background technique [0002] 1. Black smoke formation [0003] In the traditional pure oxygen conversion hydrogen production process of oil-washed dry gas and non-permeable gas in the coal-to-oil project, black smoke is often formed in the flame. [0004] Theoretical studies have found that the main component of black smoke is carbon black, and the formation of carbon black is a complex polymerization process, which is not methane cracking or heavy hydrocarbons forming carbon straight chains. Instead, the methane conversion reaction forms CH in the flame 3 , CH 2 and CH radicals (normally these radicals are fully converted to CO), and some radicals react to form ethylene (C 2 h 4 ) and acetylene (C 2 h 2 ...

AI Technical Summary

Problems solved by technology

[0010] Although the prior art has solved the problem of hydrogenation and purification of unsaturated hydrocarbons to a certain extent, it also has the problems of low comprehensive hydrogenation conversion rate (generally ≤70%) and incomplete hydrogenation;

[0011] The conventionally used hydrogenation catalysts are only active in the sulfurized state, but the downstream system requires that the raw material gas should not contain sulfur, because the raw material gas does not contain sulfur, so there is a contradiction that it needs to be sulfurized first and then desulfurized;

[0012] Existing hydrogenation catalysts only have the function of hydrogenation catalysis and cannot promote the CO shift reaction at the same time, so that the CO content in the raw gas cannot be reduced. In order to avoid the risk of metal powdering in the heating furnace tube, only materials with higher grades and lower prices can be selected. Expensive heating furnace tube material, such as INCONEL600 series, even so, cannot fundamentally solve the problem of the service life of the furnace tube

[0013] At the same time, because the traditional process cannot promote the CO shift reaction at the same time, it cannot increase the H in the outlet process gas. 2 content, only a higher feed temperature can be used to improve the reliability of the spontaneous combustion of raw gas in the reformer, so more fuel will be consumed

Images