environmental facts WHAT'S A SCRUBBER? Energy and economy are very common words in today's conversations. There is a new word--"scrubber"--which is becoming increasingly more common and, at the same time controversial. The issue centers around the means of controlling sulfur oxide emissions from plants burning high-sulfur fuels, particularly coal-fired electric generating units. The U.S. Environmental Protection Agency, after extensive public hearings, determined that scrubbers were a practical solution to this problem. A number of utilities have installed scrubber units and have worked diligently to improve their effectiveness. The American Electric Power System, on the other hand, is conducting an advertising campaign attacking scrubbers as expensive, unreliable and unnecessary. Understandably, the public is perplexed by these charges. To help clear the air, we have prepared this fact sheet which answers the most common questions asked about scrubbers. Ann L. Dore, Director Office of Public Affairs (A-107) What's a scrubber? It's a chemical-mechanical system that washes ("scrubs") sulfur oxides and particulates out of the stack gases going up the. stacks of plants burning high-sulfur coal or oil. Technically, these are flue gas desulfurization systems, or FGD's for short, but "scrubber" is a handier tag to use. Does EPA require the use of scrubbers? No. EPA requires only that the national air quality standards be met and that means controlling the emissions coming out of smokestacks. Clean fuels and stack gas treat- ment are equally acceptable. How serious is the sulfur oxide problem? A Federal Power Commission advisory committee recently reported that failure to meet the air quality standards for UNITED STATES ENVIRONMENTAL PROTECTION AGENCY • WASHINGTON, D.C. 20460 ------- -2- sulfur oxides could result each year in 6,000 premature deaths, 20 to 30 million needless days of aggravation for persons suffering from heart and lung disorders, and 6 to 10 million avoidable asthma attacks. Are scrubbers the best way to handle the problem? Considering the options, yes. The easiest solution, of course, is to burn fuels with little or no sulfur but these are precisely the fuels in shortest supply. Both natural gas, our cleanest fuel, and low-sulfur oil are best reserved for home and commercial heating since it is much easier to control a relatively few large industrial pollution sources than thousands of small sources. There is a lot of low-sulfur coal available but most of it would have to come from strip mines, which have severe environmental drawbacks. America's greatest energy resource is deep-mined coal and most of it has a high sulfur content. In order to make the most of this energy resource without damaging human health, we need scrubbers Can't the sulfur be removed before the coal is burned? Yes, but present techniques are neither efficient nor economi cal. What about tall stacks? Wouldn't they disperse pollutants over such a wide area that the impact on health would be negligible? EPA will not accept the permanent use of intermittent control systems, such as tall stacks, which merely disperse pollutants over a larger area or release them at varying times rather than reducing or eliminating them. There isn't enough information on pollution dispersion patterns to enable us to know where these pollutants would go. Recent evidence suggests that loading the atmosphere with sulfur oxides causes a build-up of sulfates--a pollutant believed to endanger human health even at low levels. In any event, if thousands of plants were to resort to this tactic, their overlapping pollution patterns would cancel out any benefits which might be gained by dispersion. And if the method can be used only by a few plants, who decides which ones get a free ride on the environment and which ones must pay for pollution control? Who needs scrubbers? Most of the sulfur pollutants get into the air from electric generating plants. Out of about 1,000 existing power plants, some 110 coal-fired plants require additional controls to meet the health-protective standards for sulfur oxi des . ------- -3- But do scrubbers work? Yes. This is a relatively new technology and there have been, and still are, bugs to be worked out. However, over the past year we have had greatly improved performance by many different operating units. Today a utility can decide to install scrubber facilities with full confidence that they can be made to operate effectively and reliably. How effective are today's scrubbers? We can reasonably expect 90 percent removal of sulfur oxides. Anything better than that might cost more than it's worth. And reliability? In 1974 units equipped with scrubbers were available for utility service about 90 percent of the time. When you consider that all generating units are shut down periodically for routine maintenance and reductions in consumer demand, 90 percent availability is excellent. Is it true that scrubbers will produce mountains of sludge? No. Lime and limestone scrubbing systems do produce large quantities of semi-solid sludge and this sludge must be disposed of carefully so that there isn't any adverse impact on the environment. But sludge disposal is not an insur- mountable problem. Wet sludge can be hardened through chemical reactions to form a dry, solid, largely inert material which has several uses, the most important of which is landfill. Numerous landfill sites are available in the United States, especially in areas where there has been strip mining. Where geographic location, space availability, or other considerations make sludge disposal impractical, alternative scrubber systems can be used. Regenerable systems, such as magnesiumoxide and catalytic oxidation, do not produce sludge. Instead, these systems regenerate the scrubbing agent and produce such valuable materials as elemental sulfur and sulfuric acid. How many scrubbers do we have now? By the end of 1974 twenty-two units will be in service. Companies plan to start 10 more units in 1975, 12 units in 1976, and 19 units in 1977. Another 30 units will begin operation in 1978 or 1979, or on dates not known today. Forty-seven of these projected units are to be installed in new plants and their start-up dates are tied to plant construction. ------- -4- How much do scrubbers cost? Cost varies depending on the type and size of the unit but they are expensive. For example, Philadelphia Electric Company will pay about $68 million to install scrubbers on three of its generating units. Can we afford such an expense at this time? Unless we close the facility producing the pollution, there is no way we can avoid paying substantial costs one way or another. Even after taking pollution control costs in account, using high sulfur coal can be far less expensive than relying on imported low-sulfur oil. If high-sulfur fuels are burned, our choice is between paying for pollution control or for the consequences of breathing bad aii—illness and shortened lives, higher medical bills, lost wages and property damage. EPA research indicates that sulfur oxides and particulates cause $11.2 billion a year in measurable "damage, compared with annual costs of less than half that amount to control it. EPA believes that it is better and cheaper to pay for the ounce of prevention than the pound of cure. 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