| Description |
Complex health and environmental issues will affect both the extent and rate of development of the nation's oil shale resource. Among these issues are concerns about land disruption, air and water contamination, waste disposal, and health and environmental problems associated with the refining and utilization of shale oil. Because many of these potential problems are intimately influenced by the physics and chemistry of the retorting process, these problems must be understood in the context of those process parameters that control the identity and behavior of products, wastes, and effluents. One question that eludes resolution concerns the nature and seriousness of water contamination caused by the extraction and processing of shale oil and the disposal of solid and liquid wastes. To develop an orderly perspective of health and environmental consequences of oil shale (or any synfuel) processing, the identity and behavior of the raw material, the fundamental chemical principles operative during processing, and the interaction of raw material and the process to yield products, effluents, and solid wastes must be understood. The utility of this approach has been demonstrated in past work (see Figure 1). Although these findings are related to leachates from solid wastes, the approach is applicable to understanding the nature and extent of all products and effluents from synfuels operations. To understand leachate composition, it is necessary to determine the water/solid interaction. Because the solid waste being considered is a dependent function of the raw shale material and the process parameters, it is necessary to first elucidate the interplay of the raw material and the process parameters in the formation of the waste and then the interaction of the waste form with water. The aqueous effluent compositions and the solid waste are dependent variables, whereas the raw shale and the process parameters are independent variables. The role of careful characterization of solids and leachates in the development of an integrated assessment of health and environmental consequences of aqueous effluents from synfuels processing is obvious. There is general agreement that retorting of oil shale presents problems regarding solid waste disposal and water contamination. Leachates from spent shales, as well as contaminated process waters, present the potential for environmental degradation whose magnitude will be closely linked to the commercial shale oil process utilized. Studies concerning the characterization of potential contaminants in various shales, shale wastes, or waste waters have been conducted; however, much of this information is not applicable to the development of predictive capabilities. A better understanding of the fundamental chemical principles operative during generation of effluents and leachates should provide a realistic framework for assessment of water management and solid waste management problems. Further research into the water quality and solid waste problems associated with recovery of shale oil is required so that control technology requirements can be specified. |
