In the previously published paper, the auther presented a method to derive longrange prospect of world energy demand from prospect of population growth. In this article, relation between energy consumption of 21 century derived from prospect of population and fossile energy resources are discussed. As the results, in 2030s petroleum and in 2050s natural gas will be consumed so far as present energy consuming pattern is kept. Further if at 2000 supply of petloleum, at 2010 natural gas and coal reach to maximum, and the level of supply of these resouces are kept, life of petroleum and natural gas are elongated about 20 years respectly. On the other hand, very large amount of primary electricity which are composed mainly nonconsumable resources will be required and amount of such primary electricity will be 1.5 X 1012 TCE (ton coal equivalent) in 21 century.
The application of the spouted bed technique to a coal gasifier has been studied in order to operate at the optimum temperature range of the gasification. The gasifier developed is composed of two parts. Jet-spouted bed reaction proceeds at the first stage in the lower part of the gasifier, and conventional spouted bed reaction at the second stage in the upper part of the gasifier. Regime maps of the jet spoutability and conventional spoutability in a column were determined. Taiheiyo coal was gasified with oxygen-steam mixtures in the dry ash mode under atmospheric pressure at temperatures up to 1350K. The effects of the oxygen/coal ratio and coal feed rate on the gasification performance were investigated. As a result, it was found that both the carbon conversion and thermal efficiency were mainly affected by the oxygen/coal ratio. The fractional conversion of carbon was 0.93 and cold gas thermal efficiency was 0.74 at the oxygen/coal ratio of 0.87. The product gases contained about 43% hydrogen and 20-30% carbon monoxide. The gasifier contains the jet-spouted bed where the partial combustion reaction mainly occurs so that the gasifier was able to be operated at around optimum gasification temperature as high as 1350K without clinkering troubles. The reactor has been demonstrated to be an efficient dry-ash coal gasifier for the production of good quality gases.
If the reverse water gas shift reaction (RWGS: CO2+ H2→CO+H2O) is selectively performed after steam reforming of light hydrocarbons with cofeeding CO2, an equimolecular mixture of H2 and CO, namely oxogas, is rationally produced. We investigated on a catalyst for high selective RWGS under flowing the simulated gas having analogous composition of off gas of steam reformer with cofeeding CO2, which includes large amount of CO. When widely accepted catalyst for RWGS, such as a NiO/ZnO catalyst, was used in our system, the methanation and the carbon deposition took place on it. Using a MoO3/ZnO, however, these side reactions were restrained, and as a result, an attempt to promote the selective RWGS was successfully achieved under flowing the simulated gas. Moreover, the catalyst showed high performance after a month in the catalyst life test.