No abstract

No abstract

The Utica and Marcellus Shale Plays in the Appalachian Basin are the fourth and first largest natural gas producing plays in the United States, respectively. Hydrocarbon production generates large volumes of brine (“produced water”) that must be disposed of, treated, or reused. Though Marcellus brines have been studied extensively, there are few studies from the Utica Shale Play. This study presents new brine chemical analyses from 16 Utica Shale Play wells in Ohio and Pennsylvania. Results from Na–Cl–Br systematics and stable and radiogenic isotopes suggest that the Utica Shale Play brines are likely residual pore water concentrated beyond halite saturation during the formation of the Ordovician Beekmantown evaporative sequence. The narrow range of chemistry for the Utica Shale Play produced waters (e.g., total dissolved solids = 214–283 g/L) over both time and space implies a consistent composition for disposal and reuse planning. The amount of salt produced annually from the Utica Shale Play is equivalent to 3.4% of the annual U.S. halite production. Utica Shale Play brines have radium activities 580 times the EPA maximum contaminant level and are supersaturated with respect to barite, indicating the potential for surface and aqueous radium hazards if not properly disposed of.

The 1990 amendments to the Clean Air Act have spurred the development of flue gas desulfurization (FGD) processes, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. Presently FGD by-product materials are treated as solid wastes and must be landfilled. However, landfill sites are becoming more scarce and tipping fees are constantly increasing, lt is, therefore, highly desirable to find beneficial reuses for these materials provided the environmental impacts are minimal and socially acceptable. Phase 1 results of a 4 and 1/2 year study to demonstrate large volume beneficial uses of FGD by-products are reported. The purpose of the Phase 1 portion of the project was to characterize the chemical, physical, mineralogical and engineering properties of the FGD by-product materials obtained from various FGD technologies being developed in the state of Ohio. Phase 1 also involved the collection of baseline economic data related to the beneficial reuse of these FGD materials. A total of 58 samples were collected and analyzed. Our results indicated the chemical composition of the FGD by-product materials were dominated by Ca, S, AI, and Si although the specific composition varies from one sample to another. Many of the elements regulated by the U.S. Environmental Protection Agency reside primarily in the fly ash. The presence of excess sorbent and reaction products causes a dilution of the concentrations of these elements in the FGD by-product materials as compared to the fly ash alone. Concentrations of the eight metals (Ag, As, Ba, Cd, Cr, Hg, Pb, and Se) regulated _)ythe Resource Conservation Recovery Act (RCRA)were below drinking water standards when measured by either the ASTM or TCLP leachate tests. Engineering tests revealed that samples made from the compacted FGD by-product materials were generally higher in strength and had greater stiffnessthan natural soils typically used in the construction of a highway embankment. Compacted densities were also lower than typical compacted soil densities. These data suggest that FGD by-product materials, used in construction of a highway embankment, would be lighter and require less right-of-way due to the possibility of constructing steeper slopes. Dry FGD by-products can react with with water to form ettringite, an expansive calcium sulfoaluminate hydrate mineral. This expansiion may affect how dry FGD byproduct is stockpiled and used by professional engineers and construction contractors. Based on analyses of the agricultural lime and supply demand relationships it was concluded that FGD by-product material, used as an agricultural lime substitute, would be entering a very competitive market. This substitution will be sensitive to transport distances and the FGD producer's willingness to subsidize its use in agricultural. In summary, Phase 1 results revealed that FGD by-product materials are essentially coal fly ash materials diluted with unreacted sorbent and reaction ...

No abstract