Improvement of Methods of Extracting and Refining Oil Shales and their Technical and Economic Evaluation

Abstract

1. The large quantities of oil and gas used for industrial purposes and the significant rise in the cost of these resources make it necessary to include in the energy balance substantial quantities of solid fossil fuels, primarily cheap coals but also oil shales, which could in the long term constitute a potential source of crude oil supply. 2. The solution of this problem depends to a large extent on the state of a country’s mineral raw materials base, the level of efficiency of shale extraction and the development of new methods of shale refining. 3. In order to reduce in situ losses, work should be speeded up on improving methods of mechanized extraction of oil shales by underground mining and methods of enrichment when the shale seam is extracted integrally in opencast mining. 4. In view of the special properties of oil shales, shale refining has to be developed in an integrated manner. Shales will then be of real value as a reserve source of additional material for the production of heat, motor fuel and chemicals. 5. With the increase in the extraction and refining of oil shales the problem arises of how to make full use of the overburden (limestone, sand, etc.) in opencast extraction and of mining and preparation dirt in the case of underground extraction. Substantial difficulties connected with the integrated utilization of mineral residues formed during refining and burning will also arise at the refining stage. 6. The development of large scale refining of oil shales involves finding a solution for a number of ecological problems, such as the disposal of large amounts of waste, water supply and air purification. In situ methods of refining oil shales are of particular interest in this connexion, as they will make a substantial contribution towards solving the waste disposal and water supply problem. 7. International co-operation in the Field of both extraction and refining is desirable if the large scale refining of oil shales is to be developed.