Japan is one of the largest energy importers in the world, depending on overseas suppliers for most of its energy resources like oil and coal. Japan depends on coal for 17% of its primary energy. Coal is the second main energy resource after oil, which makes up 30% of the world's primary energy. Especially in Asia, demand for coal is expected to increase rapidly because of economic growth and limits on the region's oil reserves.
Coal production in the Asia-Pacific coal producing countries like Australia, China and Indonesia has been facing severe conditions. For example, open cut mining has been declining, while riskier underground mining has increased. Additional technical improvements will be essential to attain the supply required for the increased demand. These coal-producing countries are requesting technical support from Japan, which has the world-leading underground coal mining technology.
Additionally, compared with other fossil fuels, coal has adverse effects on the en-vironment, such as the emssion of carbon dioxide and sulfur oxides and the generation of coal ash when coal is burned. Growing global concerns over global environmental prob-lems, such as the greenhouse effect and acid rain, may restrict smooth expansion of coal utilization.
Therefore, Japan, which depends on overseas energy resources and is the world largest importer of coal, needs to guarantee stable energy supply and demand in Asia and stable energy supply for itself. To accomplish this, Japan should promote technical cooperation for overseas coal suppliers to Japan and also research and development aimed at clean coal technology. We should also transfer clean coal technology to Asian coal-using countries to overcome coal's environmental constrains and to spread the clean use of coal throughout Asia.
This paper, based on the current situation and on future global energy supply and demand, discusses these various topics, including Japan's policy of stable overseas coal supply, strategies of clean coal technology, and technical cooperation on the internation-al level.

抄録全体を表示

China has made every effort to increase the railway transport since the foundation of the Peple's Republic of China. In 1995, Chinese railways reached 54, 615 km.
The transport distance is now 2.50 times longer than that in the foundation in 1949 and 1.12 times longer than that in the start of market-oriented reform and open-door policy in 1978.
Ministry of Railways has succeeded in modernization of railways such as electrification, double tracking and making larger the freight car. China is expect to continue 8% economic growth rate for the next fifteen years. The production of coal is estimated at 1.4 billion tons in 2000, and 2.0 billion tons in 2010.
The shortage of investment in railways will bring the shortage of the railway trans-port.
I think that the tailway trasport, if it is insufficent to invest in railway transport would be bottole-neck of the production of coal in China. It is also necessary that both the waterway transport and road transport are expanded and strengthend by investments. Thus coal and railway are essential to Chinese economy.
This paper expects that appropriate policy on the transport of coal is quite necessary for the sound economic growth in the future.

抄録全体を表示

Based on Indonesian total final energy demand, GDP (Gross Domestic Product), population history for the past 20 years, and the long-term economic policy of the Indonesian government, we estimated the energy demand structure in Indonesia to the year 2033 and then enaluated the impact of energy supply-related cost, such as energy cost and energy conversion system construction costs, on the energy supply and demand structure in Indonesia. To simplify the analysis, the total energy system cost was minimized using linear programming techniques.
As a result of this study, it was determined that if domestic crude oil and natural gas were kept at today's prices, coal liquefaction technology would be introduced ca. 2013, and a small amount of crude oil for liquid fuel demand would be imported. If domestic crude oil and natural gas prices were to be increased linearly to the international price, the importation of large amounts of crude oil would result and a smaller coal liquefaction capacity would be required compared to the above case. The reason was that the crude oil is imported upper limit on the domestic natural gas police since imported crude oil is cheaper than domestic natural gas.

抄録全体を表示

The reacivites of preasphaltenes obtained by liquefaction of Illinois No.6 coal, PA (I), and Morwell brown coal, PA (M), were studied for hydrotreating in the presence or absence of a catalyst under hydrogen pressure of 8 MPa (coal charge) and temperature range from 320 to 440°C. The feed preasphaltenes were easily converted to THE insoluble fraction during preservation at room temperature; 35 wt% of THFI from PA (I) and 60wt% THFI from PA (M). In the reaction of PA (I) without catalyst, craking of THEI to PA, cracking of PA to asphaltene and polymerization of PA to THFI were the major reactions and the production of hexane soluble fraction (HS) was scarcely observed. Especially, polymerization of PA to THEI was very remarkable at 440°C. The presence of catalyst promoted reactions to produce asphaltene and HS and prevented the formation of THFI. In the reaction of PA (M), rather large amout of HS was produced when catalyst was not used. The productions of asphaltene and HS increased by the existence of catalyst, whereas, similar yields of THEI were obtained in both cases of presence and absence of catalyst at 440°C, which suggests that catalyst may be deactivated easfly by the PA (M) reaction at 440°C.

抄録全体を表示