The Evaluation of Liquid Fuel Production Technology from Natural Gas and Coal from the Viewpoint of the Reduction of CO₂ Emission

Abstract

SYNOPSIS: -The selection of technologies for supply of electricity and liquid fuel from natutal gas and/or coal was evaluated in this paper from the viewpoint of reduction of CO₂ emission in the long run, when petroleum would not be produced. If natural gas would not be supplied enough to satisfy both demands of electricity and liquid fuel and if those technologies would not be improved in the thermal efficiency from the present practical levels, natural gas used for the electricity power generation should be replaced by coal because CO₂ emission of its system would be smaller than the system in whish coal is used for the liquid fuel production. However, if the direct coal liquefaction technolgy is improved near the level of theretical reaction, the utilization of coal for the liquid fuel production instead of the electricity pomer generation can reduce CO₂ emission in the total system. In this case, if hydrogen produced from natural gas is used for the direct coal liquefaction, CO₂ emission will be reduced much more. The integrated energy system, in which excess hydrogen in the liquid fuel production from natural gas is used for the indirect liquefaction of coal, would be useful for the reduction of CO₂ emission when the reaction heat of the steam reforming of natural gas is supplied from the outside such as high temperature gas cooled nuclear reactor.