Device and method for coproducing synthesis gas through coupling of carbon dioxide capturing process and methane reforming process

Abstract

The invention relates to a device and method for coproducing synthesis gas through the coupling of a carbon dioxide capturing process and a methane reforming process. The method comprises the following steps: reacting by virtue of methane and a first oxygen carrier in a fuel reactor so as to generate CO2 and H2O, transferring the reduced first oxygen carrier into an air reactor to react with air to supplement lattice oxygen, after oxidation restoring, and returning the first oxygen carrier to the fuel reactor for supplying lattice oxygen to the combustion reaction of methane, so as to realizecycle use; introducing methane into a reduction reactor to react with a second oxygen carrier in the reduction reactor, so as to generate synthesis gas CO and H2; and separating, introducing obtainedhigh-purity CO2 into an oxidation reactor, transferring the reduced second oxygen carrier in the reduction reactor into the oxidation reactor to be oxidized again, introducing the oxidized second oxygen carrier into the reduction rector, so as to realize cycle use. According to the method, the low-cost capturing and local conversion utilization of CO2 are realized, meanwhile, the quality and selectivity of the synthesis gas are improved, and the structure and constitution of the reactors are optimized; and the method meets the requirements of a circular economy conception.

Description

technical field [0001] The invention belongs to CO 2 Efficiency reduction and CH 4 In the field of conversion and utilization, it specifically relates to a device and method for coupling carbon dioxide capture and methane reforming process to co-produce syngas. Background technique [0002] The energy problem has always been a world problem. Under the dual pressure of resource depletion and ecological environment deterioration, it is inevitable to find clean energy. As one of the three major fossil energy sources, natural gas has the advantages of high calorific value per unit mass and low pollution in the combustion process. With the discovery of unconventional natural gas resources, the source and recoverable amount of natural gas are more abundant. Unconventional natural gas resources mainly include coalbed methane, shale gas, water-soluble gas, inorganic gas, natural gas hydrate, tight sandstone gas and shallow biogas etc. China's unconventional natural gas resources h...

AI Technical Summary

Problems solved by technology

But the process will also have 2CO=CO 2 +C,CH 4 =C+2H 2 ,CO+H 2 =C+2H 2 O and other side reactions, in which the main reaction is a strong endothermic reaction, is conducive to the occurrence of the reaction only under high temperature conditions, and high temperature increases energy consumption, and also causes side reactions to generate carbon deposits, which seriously affects the activity of the catalyst.

The reaction of POM to synthesis gas is: CH 4 +1 / 2O 2 =CO+2H 2 , the technology has a high reaction rate, and the H in the product gas 2 The molar ratio of / CO is 2, which can be directly applied to subsequent reaction sections such as Fischer-Tropsch synthesis, but this reaction needs to use pure oxygen as an oxidant, and the operation cost of preparing pure oxygen by air separation is relatively high; and pure oxygen is very easy to produce with methane Deep oxidation, which severely reduces the selectivity of syngas

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