Interest in coal is based on its abundance and availability at relatively low cost, particularly in western Canada. Coking and thermal coals are valuable export commodities. Domestically, low grade thermal coals are used primarily for generation of electric power. Coal is a high grade and abundant source of fuel and feedstock for future chemical and synfuels plants. The paper discusses special circumstances and innovative applications where coal could offer economic advantages. Specific cases which are examined include:
Beneficiation of bituminous and sub-bituminous coal by oil agglomeration to improve yields, quality, transportation costs and competitiveness of western coals in domestic and foreign markets.
The co-generation of electricity, chemicals and synfuels using flash hydropyrolysis.
Co-processing of coal, bitumen and natural gas, all abundantly available in Alberta at relatively low cost, to produce synthetic fuels using advanced process concepts for coal beneficiation and liquefaction.
Results are presented of research conducted at the Alberta Research Council relating to these topics. Cost analyses from engineering studies are used to compare different technical advances and to serve as a guide for R&D needed to improve commercial feasibility.
In Canada, interest in coal is based on its abundance and availability at relatively low cost. It is a valuable commodity. In 1982 Canadian coal production was 42.8 megatonnes valued at $1.3 billion. Of that total, bituminous coals accounted for 52%, sub-bituminous for 30%, and lignite for 18%. Approximately 29 megatonnes, or 67%, of this output was classified as thermal coal, and 14 megatonnes, or 33%, as coking or metallurgical coal (1).
Coal faces competition as a primary energy source for domestic consumption and as an export commodity. Canadian energy consumption is decreasing due to the combined effects of conservation and recession. However, in 1982 domestic coal consumption increased by 8% from 38.4 to 41.5 megatonnes and the relative proportion of the coal share of Canadian energy consumption grew from 10.3% to 11.4%. The remaining sources of total Canadian primary energy consumption in 1982 were petroleum (38.5%), hydro-electricity (26.5%), natural gas (19.3%) and nuclear (4.3%).
Comparison of the cost of energy based on the calorific values of coal, oil and gas shows an inherent advantage for coal if it can be upgraded conomically to higher energy densities.
$0.6/Gigajoule ($10/tonne) is a typical cost of coal produced for power plants in Alberta and Saskatchewan.
$1.0/GJ ($6/bbl) is a typical cost of "old" conventional oil in Alberta excluding royalty and taxes.
$1.4/GJ ($1.5/100 scf) is a typical cost to bulk users of natural gas in Alberta.
$3.)/GJ ($20/bbl) is a typical cost of heavy oil (e.g. Lloymillster) excluding royalty and taxes.
$5.8/GJ ($35/bbl) is the current world oil price.
The challenge for thermal (and coking) coal is to improve the quality and reduce the cost so as to be competitive with other countries where considerable investments have been made in research and infrastructure.