METHOD FOR IMPROVING FISCHER-TROPSCH SYNTHESIS AND RECYCLING EXHAUST GASES THEREFROM

摘要

A method for improving Fischer-Tropsch synthesis and recycling exhaust gases therefrom. The method includes: 1) transforming raw gas for Fischer-Tropsch synthesis using a water-gas shift reaction, transporting the transformed raw gas to a Fischer-Tropsch synthesis device for Fischer-Tropsch synthesis in the presence of a Fe-based or Co-based catalyst; 2) introducing exhaust gases from the Fischer-Tropsch synthesis device to a first pressure-swing adsorber for hydrogen recovery; 3) introducing the exhaust gases from 2) to a second pressure-swing adsorber for methane recovery; 4) returning part of the hydrogen obtained from 2) to 1) to mix with the raw gas, and transforming a resulting mixed gas to adjust a hydrogen/carbon ratio of the raw gas; and 5) introducing the methane in 3) to a methane reforming device to reform the methane whereby yielding syngas having relatively high hydrogen/carbon ratio, and transporting the syngas to 1) to mix with the raw gas.

主权项

1. A method for improving Fischer-Tropsch synthesis and recycling exhaust gases therefrom, the method comprising:
1) transforming raw gas for Fischer-Tropsch synthesis using a water-gas shift reaction: CO+H2O=>CO2+H2, transporting the transformed raw gas to a Fischer-Tropsch synthesis device for Fischer-Tropsch synthesis in the presence of a Fe-based or Co-based catalyst, controlling a reaction temperature of the Fischer-Tropsch synthesis at between 150 and 300° C. and a reaction pressure of between 2 and 4 MPa (A), to yield a liquid hydrocarbon product; 2) introducing exhaust gases from the Fischer-Tropsch synthesis device to a first pressure-swing adsorber for hydrogen recovery, and controlling a purity of the hydrogen at 80-99 vol. %; 3) introducing the exhaust gases from step 2) to a second pressure-swing adsorber for methane recovery, and controlling a purity of the methane at 80-95 vol. %; 4) returning part of the hydrogen obtained from step 2) to step 1) to mix with the raw gas, and transforming a resulting mixed gas to adjust a hydrogen/carbon ratio of the raw gas for Fischer-Tropsch synthesis; and 5) introducing the methane in step 3) to a methane reforming device to reform the methane whereby yielding syngas having relatively high hydrogen/carbon ratio, transporting the syngas to step 1) to mix with the raw gas, and transforming a resulting mixed gas to adjust a hydrogen/carbon ratio of the raw gas.