AN INVESTIGATION OF THE DIXIE VALLEY GEOTHERMAL FIELD, NEVADA, USING TEMPORAL MOMENT ANALYSIS OF TRACER TESTS
The method of analysis of the first temporal moment (mean residence time) of tracer return data was utilized to investigate the swept volume and fluid velocity between pairs of injection and production wells in the Dixie Valley geothermal field. Calculations were made using a spreadsheet program available from the Idaho National Laboratory. Jointly sponsored industry–government research at the Dixie Valley field provided several tracer tests over many years, and a test of six, chemically similar tracers, injected between 1998 and 2001, provided the tracer concentration data used in this study. The calculated parameters of mean residence time, fracture volume in contact with the tracer, fluid velocity, and heterogeneity of the reservoir were compared to published descriptions of the reservoir to evaluate their usefulness in refining the conceptual model of the Dixie Valley geothermal reservoir. Temporal moment analysis provided more information about the fractured fluid path between wells and the volume of the reservoir contacted by the tracers. Tracer injection in the center of the Dixie Valley field and production of that tracer in the northeastern and southwestern production wells clearly demonstrated that no barrier to flow exists between the two areas of producing wells.
Predicting thermal breakthrough in heterogeneous media from tracer tests
Analysis of the conservation equations demonstrates that the ratio of fluid-to-temperature velocities is a constant, even in heterogeneous media. Because tracers move at the bulk fluid velocity, tracer test analysis can be used to predict temperature declines at production wells that result from injection. Tracer histories are transformed into predicted temperature histories through a simple variable transformation. Examples demonstrate that the method works well for single-phase flow in heterogeneous (but porous) media. In the presence of strong permeability correlation (layering), the method's accuracy degrades somewhat; the onset of cooling, however, is still predicted reasonably accurately.
Production of new antituberculosis drug and other medical preparations by electron beam treatment
Abstract Possibility of electron beam usage for immobilization of hydrazidum of an isonicotinic acid (HIA) on dextrane was studied to produce a drug for treatment of a tuberculosis. As a result of irradiation of dextrane the processes of oxidation and formation of polysaccharide occur due to carbonyl groups which are to link isoniasidum. The HIA immobilized on dextrane may be used as an effective medical preparation having prolonged action for action on endo and extracellular population of Micobacterium tuberculosis .