Pollution-Control Costs: A Status Report

摘要

The purpose of this study is to assess the economic, energy, and environmental impacts of possible New Source Performance Standards (NSPS) for 68 combinations of boiler size, emission standards, load factor, and combustion/control technologies. The results of the study show that Low-Btu gasification is not competitive with direct coal combustion for any level of control in the systems studied. The market for LBG technology will depend primarily on the availability and relative prices of petroleum and natural gas. Direct firing of low-sulfur coal is the least-cost option for Level-1 control and gives by far the lowest level of SO sub 2 emissions. However, AFBC is economically competitive with low-sulfur coal at the 75 and 150 million Btu/hr sizes (within the uncertainty of the estimates) and is more attractive than the other options. For Level-2 control, dry FGD was found to be competitive with wet FGD, but still more expensive than AFBC. Although dry FGD was not evaluated for high-sulfur-coal applications in this study, recent experience with a retrofitted spray dryer/fabric system at ANL has indicated that such systems should also be competitive for high-sulfur coals. At level 3, AFBC and wet FGD are the favored technologies for the larger boilers. SRC is nearly competitive at 150 and 75 million Btu/hr, and is clearly the economic choice at 30 million Btu/hr, especially for the lower load factor. Although SNG was not evaluated for the smaller boilers, it is expected to be competitive with SRC in those cases at the stringent control level. The most attractive technology options as determined by this study depend on boiler size, load factor, and level of control required. Direct combustion is favored for larger boilers, while coal-derived synfuels and petroleum-based fuels are most attractive for small boilers operating at low load factors. The systems approach to technology comparisons reveals important facets that would not be shown by narrowly focussed case studies. (ERA citation 08:019576)