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EPA Says Scrubbers Necessary for Health Protection Under Coal Conversion Plan

[EPA press release - July 14, 1977]

President Carter's Energy Plan calls for maximum conversion of this nation's electric power plants from oil to coal combustion. EPA Deputy Administrator Barbara Blum today cited a new report affirming that flue gas desulfurization systems (scrubbers) are the best means of protecting public health from this monumental shift in energy priorities.

"To help control increased sulfur dioxide air pollution from this massive coal conversion, the Energy Plan recommends that tall new power plants install best available pollution control technology," Blum said, "and as our report points out, the only process with high sulfur dioxide removal efficiency widely available now is scrubbers."

The report, titled "Flue Gas Desulfurization in Power Plants, Status Report" (April 1977), summarizes worldwide progress of scrubber technology in controlling sulfur dioxide (SO2) pollution from power plants.

EPA set national health standards in 1971 for SO2, which can irritate the upper respiratory tract and damage lung tissue, as well as yellowing plant leaves and eating away iron, steel, marble and other solid materials. The approximately 970 power plants that burn oil and coal to produce electricity in America are the major sources of this pollutant.

"The report states that in the last five years scrubbers have been substantially refined and improved," Blum said. "Scrubbers are now offered for sale by at least 13 reputable U.S. firms, and many variations of the basic process are being developed."

"Operational experience has shown that most scrubbers can remove 80 percent or more SO2 from plant emissions, and do so reliably," Blum added.

"EPA is aware of the problems some power plants face in installing scrubbers. They are expensive to install and operate, and some equipment problems have occurred in use. However, substantial progress has been made in eliminating the problems; we also believe that scrubber installation and operation costs are reasonable in the long run.

"An unfortunate by-product of scrubber use is the production of sulfur waste material or 'sludge'. Lime and limestone scrubbers--the most widely-used types--produce large quantities of sludge, but several commercial methods are now available to solidify this waste material. This solid sludge can be disposed of in landfills without significant adverse effect on the environment. Other disposal methods are being evaluated.

"Some of the new processes are 'regenerable' systems (Wellman-Lord being the most important) which produce a sulfur waste product, such as sulfuric acid, that can be sold and bring in additional revenue for the power plant.

"I firmly believe that the electric power industry is coming around to a positive acceptance of scrubbers. Fifty power companies have now installed or are building or planning 119 scrubber systems. This is a 270 percent increase over the 44 systems planned, in construction or installed by 24 companies in Fall 1973, when EPA held special hearings on actions necessary to bring power plants into compliance with SO2 air standards."

Among the subjects covered in the report are:

  1. historical background;
  2. related studies;
  3. power plant compliance with air pollution regulations;
  4. names of companies using scrubbers;
  5. Japanese scrubber experience;
  6. technological progress of the five main scrubber systems, the Lime and Limestone, Wellman-Lord, Double Alkali, Chiyoda, and Magnesium Oxide;
  7. description of systems currently in operation; and
  8. scrubber costs.