Based on our previous study of the Chinese energy structure up to the year 2010, the impact of energy supply related costs, such as energy price and energy conversion capital cost, on the energy supply and demand structure in China to the year 2025 was evaluated. To simplify the analysis, the total energy system cost was minimized using linear programming techniques.
As a result of thisstudy, it was clarifed that if crude oil imports to China were limited to 200Mtoe/year, which corresponds to the quantity imported by Japan in 1990, coal liquefaction technology would be introduced at ca. 2020, as the domestic crude oil supply would have been depleted by that time . To meet gasoline demand, a larger quantity of coal must be liquefied because the gasoline fraction in oil fromcoal liquefaction is smaller than that of crude oil. But simultaneously the consumption of raw coal in the final energy demand sectors, the industry and the residential sectors would decrease because gas and heavy oil produced by coal liquefaction would be used in those sectors.

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Effects of the amount of iron/sulfur catalyst on yields and hydrogen transfer of Victorian brown coal were investigated using two kinds of process solvents derived from the two-stage brown coal liquefaction (BCL) process; one is a solvent recycled in primary hydrogenation (PY-S, non-hydrogen donor solvent), and the other is a solvent recovered from secondary hydrogenation over Ni-Mo catalyst (SD-S, hydrogen donor solvent). In addition, the influence of hydrogen pressure and reaction time were also investigated using these solvents in the presence of the catalyst.
SD-S was effective under non-catalytic and lower hydrogen pressure conditions compared with PY-S, but distillate yield was low under these conditions. On the other hand, PY-S provided higher distillate yield and hydrogen efficiency (defined by ratio of distillate yield to amount of hydrogen transferred to all liquefaction products) than SD-S under the condition of high hydrogen pressure and high catalyst concentration. These results indicate that the effects of the catalyst on liquefaction reaction is small in hydrogen donor solvent, and non-donor solvent is effective under severe conditions. The hydrogen efficiency increased with increases in pressure and catalyst concentration, and showed a peak at the optimum reaction time, which depended on the conditions and solvent properties.

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IGCC systeme are expected to be of practicable use in the near future, in view of its prominent environmental compatibility and higher thermal energy efficiency. The highest themal efficiency is achievable when the gas cleanup is conducted at a high temperature and pressure. To make the most of these characteristics of high thermal efficiency that is associated with this IGCC, development of hot gas cleanup technology is essential.
IGC Association installed a 200t/d pilot plant in 1990 at Nakoso site, and a hot gas cleanup facility that is composed of the fluidized-bed desulfurization unit and the granular bed dust collector has been operating. Also, Fixed-bed type and Moving-bed type hot gas cleanup facilities were installed in 1993. The characteristics of desulfurization and dust removal were investigated using these facilities. Sulfur and dust concentration in the clean gas were under the target value. From its result, we confirmed that all the 3 types hot gas cleanup processes have high performance.

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