05.07.2009
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Watertight enclosure from which water is pumped to expose the bed of a body of water in order to permit the construction of a pier or other hydraulic work
A brown or black sedimentary rock that forms from accumulated plant debris. A combustible rock that contains at least 50% (by weight) carbon compounds
Policy that determines that it is necessary to develop more coal generated power stations rather than natural gas or nuclear for instance. Countries, such as China, may decide on a more coal-based energy policy if they feel that geopolitics and competition for gas supplies have intensified too much. In fact, China has been establishing an additional 1,000 MW of coal power generated stations per week.
Process of converting solid coal into natural gas before it is used in a power station to render it more environmentally friendly. Gasification exposes coal to temperatures that would normally cause the coal to combust but by carefully regulating the amount of oxygen in the gasifier and adding steam, the coal does not burn but rather separates into syngas. Syngas is a mixture of carbon monoxide and hydrogen. The syngas can then be ‘shifted’ with the addition of more steam to produce more hydrogen and to convert the carbon monoxide into carbon dioxide (CO2). The gasification of coal and other substances (petcoke, refinery bottom waste, biomass etc.) is not new. For example, China has been successfully gasifying coal for decades for ‘town gas’, chemical feedstock and for its domestic fertilizer industry.
Coefficient of performance used to measure the efficiency of heating and cooling systems. It is the ratio of useful energy output (heat removal or heat delivery) to useful energy input