1、目录外文一2原文2译文8外文二12原文12译文1519外文一原文MACROSCOPIC TO MICROSCOPIC STUDIES OF FLUE GAS DESULFURIZATION BYPRODUCTS FOR ACID MINE DRAINAGE MITIGATIONINTRODUCTION The use of flue gas desulfurization (FGD) systems to reduce SO2 emissions has resulted in the generation of large quantities of byproducts. These an
2、d other byproducts are being stockpiled at the very time that alkaline materials having high neutralization potential are needed to mitigate acid mine drainage (AMD). FGD byproducts are highly alkaline materials composed primarily of unreacted sorbents (lime or limestone and sulfates and sulfites of
3、 Ca). Approximately 20 million tons of FGD material were generated by electric power utilities equipped with wet lime-limestone FGD systems according to the lastest calculation (l993). Less than 5% of this material has been put to beneficial use for agricultural soil amendments and for the productio
4、n of wallboard and cement. Four USGS projects are examining FGD byproduct use to address these concerns. These projects involve 1) calculating the volume of flue gas desulfurization (FGD) byproduct generation and their geographic locations in relation to AMD, 2) determining byproduct chemistry and m
5、ineralogy, 3) evaluating hydrology and geochemistry of atmospheric fluidized bed combustion byproduct as soil amendment in Ohio, and 4) analyzing microbial degradation of gypsum in anoxic limestone drains in West Virginia. UNITED STATES FGD DATA BASE The Industrial Minerals Branch of the Office of M
6、inerals Information (formerly the U.S. Bureau of Mines) at the USGS has developed a Geographic Information System (GIS) that can be used to provide information on the availability and proximity of FGD byproducts and potential markets, such as wallboard plants, portland cement industries, and AMD pro
7、blem areas. With this information, we are able to assess the economic potential of FGD byproduct markets on a national basis for the first time. The distribution of electric power utilities equipped with FGD units is widespread. FGD byproduct production and accumulation to the year 1998 was forecast
8、 by the Energy Information Administration. At current production rates, as much as 200 million metric tons of FGD materials will be generated and stored primarily in landfills by the year 2000. This is an enormous volume of highly alkaline material. An important objective, therefore, is to character
9、ize FGD byproduct chemistry and mineralogy to identify beneficial and deleterious components. CHARACTERIZATION OF FGD FEED LIMESTONE AND BYPRODUCTSThe USGS, the Kentucky Geological Survey, and a Kentucky utility have initiated a project to gather information on the chemistry and mineralogy of feed c
10、oal, feed limestone, fly ash, bottom ash, and FGD byproduct at a Kentucky power plant. Samples of each of these materials are being collected at monthly intervals. The wide variety of analyses on each include the concentration of as many as 50 elements; mineralogy (X-ray diffraction, optical petrogr
11、aphy); modes of occurrence (scanning electron microscopy, microprobe analysis, selective leaching); organic geochemistry; radionuclide analysis; toxic characterization of leaching procedure (TCLP); and column leaching. Results from this data base will be made available and are expected to provide in
12、sights into the influence of chemistry and mineralogy of the feed limestone and coal on the chemistry of FGD sludges. An important objective is to use the data to determine the relative reactivity of the various byproduct components in surface and ground water. SURFACE AND GROUND WATER CHARACTERIZAT
13、ION OF FGD BYPRODUCT UTILIZATION AT DEMONSTRATION SITE IN TUSCARAWAS COUNTY, OHIOFGD byproducts were applied at an abandoned surface coal mine in Tuscarawas County, Ohio to neutralize AMD, learn about changes in water chemistry, and increase soil alkalinity to aid in revegetation. This research is a
14、 joint effort between the USGS Water Resources Division (Ohio District) and The Ohio State University. Dry FGD byproduct was applied to the surface in late 1994 during reclamation of the 45-acre Fleming site. Pre-reclamation surface-water discharges from the site were acidic (pH 2.9 to 5.5) and eros
15、ion was severe owing to lack of vegetation. FGD materials were applied to six 1-acre test watersheds on bases of 4-feet-thick acidic mine spoil. Three replicates of 3 reclamation treatments were applied to each spoil surface, either as (1) standard reclamation practice of 8 in. of topsoil amended wi
16、th ag-lime; (2) 8 in. of topsoil amended with 125 tons/acre dry FGD byproduct; or (3) 8 in. of topsoil amended with a blend of dry FGD byproduct and yard-waste compost. In addition, FGD materials were applied at a rate of 125 tons/acre to reworked minespoil in a buffer zone that surrounds the test plots. Physical, mineralogical, and engineering properties of FGD materials used at the Fleming site have been extensively investigated
