Hundreds of tough decisions on SO2 reduction
The future viability of a coal-fired plant is shaped by the hundreds of tough decisions that need to be made due to recent rules to limit SO2 emissions. Each of these decisions is continually analyzed in FGD Decisions published by the McIlvaine Company. This new service utilizes a decision-tree format with thousands of pages of analysis supplemented by alerts and discussion.
According to Robert McIlvaine, president of McIlvaine, “millions of dollars are being wasted as each utility duplicates the effort of the others in organizing and analyzing the same alternatives. This new system eliminates this duplication.”
Flue gas desulfurization (FGD) represents an investment to the power company of 10 percent of the entire capital cost of a new plant. With some older plants, the cost of the scrubbers will be more than the original plant cost. Operating costs will be the second largest (coal purchases are the biggest cost). Decisions, which cause a change of just a few percent in these costs, have a big impact on profitability.
FGD decisions have the potential to substantially reduce or increase emissions of pollutants other than SO2. Some of the most important decisions involve options which impact emissions of these other pollutants. Several utilities have recently made poor choices. When operating the combination of newly installed NOx control and FGD systems, the deposition of acid mist in nearby areas was sufficient to curtail plant operations. Millions of dollars in lost revenue was accompanied by substantial payments for damage done to structures and property.
FGD systems can remove much of the fine particulate matter including toxic metals, and thus eliminate the capital expense of upgrading precipitators. Some scrubber types, with the same SO2 removal efficiency, are more efficient in reducing particulate than others. Thus careful analysis is needed in scrubber selection.
The tendency is to specify a limestone forced oxidation system in every circumstance regardless of the site specific differences for individual plants. Older plants with shorter life expectancy should consider less capital intensive options. Plants on seacoasts can consider using seawater as a scrubbing medium (regulations vary by county).
Plants with access to inexpensive fuel sources such as high chlorine coals, biomass, and petroleum coke need to weigh the reduction in fuel costs against increased capital costs to meet emission limits.
The potential to reduce mercury with the right FGD system is of high importance. Recent experience indicates that 90 percent mercury reduction in the scrubber can be achieved even where elemental mercury is substantial. New developments with this technology are being constantly announced. The decision maker is therefore challenged to stay abreast of the latest developments. The “Alerts” function in FGD Decisions provides the basis to determine when previous decisions need to be reviewed.
For more information on FGD Decisions, click on: http://www.mcilvainecompany.com/FGDdecbroch/Default.htm .
Bob McIlvaine
847-784-0012
rmcilvaine@mcilvainecompany.com