Contents Notes |
"Current and projected uses of coal have resulted in several proposals for coal slurry pipelines in the eastern part of the United States. While several researchers have reported on the water quality aspects of western coal slurries, less work has been done with respect to eastern coals. An experimental study was conducted at the University of Central Florida from 1982 to 1983 with slurries of 50 percent eastern Kentucky coal and 50 percent water. Experiments were conducted with and without the addition of a corrosion inhibitor. Twenty-nine water quality parameters were measured as a function of pumping time in a 12-meter (40-ft) long, 2.54 cm (1 inch) diameter pipeline constructed for this study. Also, the treatability of the 10-day slurry filtrate was assessed using both lime and alum addition. By about the fourth day in the pipeline, most parameters had reached equilibrium values. As expected for this high-ash, medium-sulfur coal, sulfates, TDS, and conductivity in the slurry filtrate started high and increased with time. Dissolved oxygen quickly dropped to near zero. Concentrations of several heavy metals were substantial, but organics were generally very low, about 5-10 mg/L. Trihalomethane formation potential was quite low, never exceeding 35 ppb. Although the samples were consistent in any one run, samples from different runs on the "same'" coal were significantly different. Addition of the corrosion inhibitor increased the concentrations of sulfates, TDS, and several other parameters. The characterization of this particular coal slurry was compared with those of several western coal slurries reported in the literature." |