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Energy needs versus environmental pollution: a reconciliation?
Authors:L Green
Abstract:In this article I have presented, for discussion, a proposed system for energy generation by which the principal sources of environmental pollution by power plants could be eliminated. For stationary power plants the concept appears feasible technically and, according to my " horseback estimates," perhaps economically as well, depending upon the economic value of the by-products of sulfur, CO(2), water, and possibly nitrogen, and upon the price we are willing to pay for a clean environment .Thus, a more thorough engineering and economic analysis to explore these and other factors in greater depth seems warranted. In the case of turbine-driven vehicles, the technical and economic feasibility of widespread distribution and handling of the fuel constitutes a serious question, but one which deserves equally serious consideration before the possibility is discounted. The reports of the cited study panels notwithstanding, the technology required for the proposed system exists today, with one exception. This exception (which is not essential for trial of the system but will be required for its complete fruition) is the development of a nuclear reactor for the prime purpose of delivering process heat for the steam reforming of natural gas and, ultimately, for gas production from coal in a continuous process, such as those discussed by Pieroni et al. (16). Today's intermittent processes of coking and gas production are both archaic and themselves large sources of atmospheric pollution, and a development program aimed at advancing the technology of the coal industry in this regard would seem long overdue. The report of the PSAC Environmental Pollution Panel recommended "demonstration of the feasibility and economy of new developments for abating or controlling pollution through their use at Federal installations" and suggested the coalburning TVA power plants as a likely place for such demonstration. This suggestion is doubly appropriate since the TVA is in a region of subnormal " atmospheric ventilation" (8). By design these plants are adjacent to the AEC's Oak Ridge National Laboratory, and such a location would seem ideal for an experiment on the wedding of nuclear and fossil sources of energy. In comments on a preliminary draft of this article, proponents of "conventional " nuclear power pointed out that such power is hard to beat on the basis of cost, and that dissipation of heat to the air by way of cooling towers can also be accomplished in conventional plants (17). These observations are individually correct but not compatible: the low power costs cited are for very large plants of the order of 1000 mega-watts lectrical) and larger], and the costs of cooling towers and associated equipment needed to dissipate such large amounts of heat of the order of 2000 megawatts (thermal)] to air from a closed cycle would offset the power cost advantage of the large plant. In regard to the proposed use of nuclear process heat, Weinberg (20) has expressed doubt that much advantage can be derived from this approach because the temperatures involved are too high for low-cost reactors, and heat transfer from surfaces could involve materials problems. In the case of gas production, this is indeed an anticipated problem-not a technologically insuperable one, but a problem of reducing the cost of the materials required (16). Indeed, Weinberg himself has mentioned this possible use of nuclear heat in a recent publication discussing the steam reforming of coal to liquid fuel(21). Also, an improved process for synthesizing methane from lignitec has recently been reported (22). Since the earlier studies date back a decade, a new look at the problems and costs involved relative to the benefits to be derived (not the least of which could be new vigor for the coal industry) would seem to be in order. In the case of steam reforming of natural gas, the temperature level (about 1500 degrees F) is such that the technology is available today, and a process-heat-reactor design study could be initiated without awaiting further developments.
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