History of SO2 removal system at the Meramec plant of union electric.

In line with the then emerging air pollution control regulations Union Electric installed a limestone injection wet scrubber sulfur dioxide removal system on an intermediate size coal-fired utility boiler at its Meramec Power Plant on an experimental basis in September, 1968. Approximately 3 years of operation many difficulties were encountered with plugging and scaling of various system components by calcium sulphate. As a result of this experience along with related experiences by other utilities employing similar systems, the experiment was terminated in June, 1971. As a result of the experiences gained, however, second generation experiments in sulfur dioxide removal have been initiated elsewhere with the hope of improved performance. A number of experimental projects are still under tests. Costs in resources, reliability, and disposal of residual by-products are matters of great concern. The ture cost of sulfur dioxide removal systems in dollars and resources is not well known and perhaps a reevaluation of current and future SO2 removal projects is in order at this time before additional resources are committed.