Environmental problems in the Estonian oil shale industry
Abstract
In Estonia technologies for oil shale mining and consuming have been continuously developed for more than 80 years. By March 2006 one billion tonnes of oil shale had been produced in Estonia. Since the 1960s, Estonia has been the largest oil shale producer and consumer in the world. In the 1980s about two-thirds of the world's oil shale output came from Estonia. Serious problems in the mining complex are connected with large losses of oil shale at mining and enrichment (more than 30%) and voluminous dewatering (25 m3 per tonne of oil shale). After mining and beneficiation, much limestone remains unused and is deposited in waste dumps. Oil shale waste and waste heaps may be considered a rather innocent production residue; however, from time to time they are subject to self-ignition. Following