Coal in the UK: the past becomes the future

The British National Coal Board (NCB) and British Gas, together with the British government, are developing technology to supplement diminishing supplies of oil and natural gas with substitutes manufactured from coal. Direct burning of coal is expected to utilize fluidized-bed combustion, and there are plans to raise power generation efficiency by installing a gas turbine in the combustor exhaust. Rapid pyrolysis is known to produce volatile materials in substantially greater yield than pyrolysis, and the NCB is now investigating this method to produce chemical feedstocks such as acetylene and aromatic carbons. A more recent development is flash pyrolysis. This has arisen from the discovery that by rapidly heating coal entrained in steam to temperatures up to 1740/degree/F, with a time exposure of two seconds, the total yield of tar and gas increases and the proportion of each is changed as the temperature increases. Coal liquifaction by the Coal Research Establishment process has yielded up to 50 gal. of gasoline and a further 80 gallons of other distillates are produced which are suitable for use in diesel engines and gas turbines. Coal gasification in a fluidized bed appears the most promising way of producing synthetic natural gas.