Orchid Woods and Floating Islands – the Ecology of Fly Ash
The combustion of coal in modern power stations leaves a residue of fly ash (pulverised fuel ash of PFA) which is removed from exhaust gases using electostatic precipitators. Approximately 10 million tons of PFA are produced in the UK per year, of which approximately half is sold to the construction industry. The remainder is disposed of as a waste material, either in lagoons or mounds. In 1979 there were 1,400ha of land known to have been used for PFS disposal, of which 1,000ha had been restored to agriculture (Gillham 1979).