Impact of modification/reconstruction of steam generators on SO/sub 2/ emissions. Final report

This report discusses the terms 'modification' and 'reconstruction' as related to New Source Performance Standards (NSPS) for SO/sub 2/ emissions from coal-fired boilers greater than 250 million Btu per hour input. An analysis of current boiler technology indicates there are few physical or operational changes that would qualify as modifications or reconstruction in the sense of altering SO/sub 2/ emissions from a boiler system. This is true because SO/sub 2/ emissions are a function of the sulfur content of the fuel and are not affected by furnace and boiler design and operating parameters. Two situations which could be construed as modifications affecting SO/sub 2/ emissions would be conversion of a wood burning facility to coal or the use coal/oil slurries in a boiler originally designed for oil. Neither of these are expected to be widespread occurrences. First, there are few wood-fired boilers in the size range covered by NSPS and, secondly, it is doubtful there would be any incentive for such units to switch from a cheap waste fuel to a more expensive primary fuel. Boilers using coal/oil slurries have only recently been proposed and are still at an experimental stage. Also discussed in this report are some of themore » constraints that could inhibit an existing facility from installing flue gas desulfurization equipment.« less