The economic analyses covering physical desulfurization of coal followed by flue gas desulfurization and flue gas desulfuriztion used alone for selected coal source-user combinations indicate that economic generalizations must be approached with caution. The range of variability is such that each case must be individually assessed. In general, available data indicate that many coals can be beneficiated to remove ash and sulfur at an attractive net cost. These coals with reduced ash and sulfur content levels are often not too far removed from the sulfur content levels required to meet environmental standards in some areas traditionally served by these coals. When coal can be physically cleaned to a level not too far removed from that required to meet emission standards, flue gas desulfuriztion treating only a portion of the flue gas would satisfy environmental constraints. In many cases the net cost of physical desulfurization followed by flue gas desulfurization is substantially less than that of flue gas desulfurization alone. This is due to the net economics associated with physically cleaning coal combined with the substantially lower flue gas desulfurization costs. In essence, the net cost (i.e., costs less benefits) associated with physical desulfurization would be less than the additional cost if flue gas desulfurization was used alone. For existing powerplants, the real costs for flue gas desulfurization systems are especially expensive owning both to higher capital costs and to the shorter economic lives of the systems. In many such cases, the use of physical desulfurization followed by flue gas desulfuriztion can be particularly attractive. (ERA citation 04:052508)

Prepared by The Hoffman-Muntner Corporation, under Contract no. J0155171. Includes bibliographical references (pages 68-69).