The effect of biomass immobilization support material and bed porosity on hydrogen production in an upflow anaerobic packed-bed bioreactor

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Preliminary Floatation Tests on the Beneficiation of a Low-Grade Montana Bituminous Coal.

Coal is an aggregation of vegetal matter with varying small amounts of mineral and animal matter which have been so changed by the processes of sedimentation, decay and metamorphism that it has become a dense, dark, combustible substance. It occurs in beds varying in thickness from one foot or less to over 300 feet. The horizontal extent of a bed is sometimes continuous over an area as large as the State of Montana.

Effects of Coalbed Methane Production on Stream Flow

Coalbed methane production has the potential to reduce instream flows in Powder River Basin streams. Quantifying this effect is difficult, but important, for water users in both Wyoming and Montana. Isotope tracing of coal aquifer groundwater entering the streams can help.

DEVELOPMENT AND APPLICATION OF SHORT-TERM MUTAGENICITY AND CYTOTOXICITY BIOASSAYS FOR INTEGRATED HEALTH ASSESSMENT STUDIES OF COAL FLY ASH EMISSIONS

Two respirable coal fly ash samples ((LESSTHEQ) 3(mu)m), one from a pressurized fluidized-bed combustion miniplant and one from a conventional combustion power plant, were investigated for physical properties, chemical composition and biological activity. Electron microscopy illustrated irregularity in fluidized-bed combustion fly ash and sphericity in conventional combustion fly ash. Elemental analysis of these samples showed differences in trace elements. Both fly ash samples were toxic in rabbit alveolar macrophage and Chinese hamster ovary cell systems in vitro. The macrophages were more sensitive to toxicity of fly ash than the ovary cells. For measuring the cytotoxicity of fly ash, the most sensitive parameters were adenosine triphosphate in the alveolar macrophage system and viability index in the hamster ovary system. Intact fluidized-bed combustion fly-ash particles showed mutagenicity only in strains TA98 and TA1538 without metabolic activation in the Ames Salmonella assay. No mutagenicity was detected in bioassay of conventional combustion fly ash particles. Solvent extraction yielded more mass from fluidized-bed combustion fly ash than from conventional combustion fly ash. The extracts of fluidized-bed combustion fly ash showed higher mutagenic activity than conventional combustion fly ash. These samples contained direct-acting, frameshift mutagens.^ Fly ash samples collected from the same fluidized-bed source by cyclones, a fabric filter, and a electrostatic precipitator at various temperatures were compared for particle size, toxicity, and mutagenicity. Results demonstrated that the biological activity of coal fly ash were affected by the collection site, device, and temperature.^ Coal fly ash vapor-coated with 1-nitropyrene was developed as a model system to study the bioavailability and recovery of nitroaromatic compounds in fly ash. The effects of vapor deposition on toxicity and mutagenicity of fly ash were examined. The nitropyrene coating did not significantly alter the ash's cytotoxicity. Nitropyrene was bioavailable in the biological media, and a significant percentage was not recovered after the coated fly ash was cultured with alveolar macrophages. 1-Nitropyrene loss increased as the number of macrophages was increased, suggesting that the macrophages are capable of metabolizing or binding 1-nitropyrene present in coal fly ash. ^