Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xi, 106 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 96-98).

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xxiii, 271 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 268-271).

This study investigates peculiarities of the filtration combustion (FC) of the gaseous fuel-air mixtures in a porous inertia media (PIM). Combustion wave velocities and temperatures were measured for hydrogen-air, propane-air and methane-air mixtures in the PIM at different mixture filtration velocities. It is shown that the dependences of the combustion wave velocities on the equivalence ratio are V-shaped, It was further confirmed that the FC in the PIM has more contrasts than similarities with the normal homogeneous combustion. One of the interesting observations in the present study, which is not common in normal homogenous combustion, is the shifting of the fuel-air equivalent ratio at the minimum combustion wave velocity from the stoichiometric condition (¢ = 1). For a hydrogen-air mixture, the fuel-air equivalence ratio at the minimum combustion velocity shifts from the stoichiometric condition to the rich region, while for the propane-air and methane-air mixtures the fuel-air equivalence ratio at the minimum combustion velocity shifts toward fuel-leaner conditions. The measured maximum porous media temperatures in the combustion waves are found to be weakly dependent on the mixture filtration velocities. In general, the effects of the mixture filtration velocities on the measured maximum porous media temperatures are not significant.

Abstract This study was aimed at introducing multistage filtration (MSF) (a combination of slow-sand filtration (SSF) and pretreatment system - horizontal flow roughing filter (HRF)) as an alternative water treatment technology to the conventional one. A pilot- plant study was undertaken to achieve this goal. Evaluating the MSF performance vs. the existing conventional system in removing selected physical and chemical drinking water quality parameters together with the biological water quality improvement by the MSF without chemical use was done. Evaluation of the effectiveness of the MSF system utilizing locally available material, i.e. gravel, improved agricultural waste (charcoal maize cobs) and broken burnt bricks as pretreatment filter material was also done The benchmark was the Kenya Bureau of Standards (KEBS) values for the selected parameters. Results showed that with proper design specifications, MSF systems perform better than conventional systems under similar conditions of raw water quality and environmental conditions. The tested locally available materials can also be effectively used as pretreatment media with each allowing a filter run greater than 82 d and therefore could serve as alternatives where natural gravel is not readily available. With special reference to the bacteriological quality improvement, the MSF greatly improved the bacteriological quality of the water recording removal efficiencies of over 99% and 98% respectively for E. coli and total coliforms. Despite the observed performance, MSF should be complemented with chlorination as a final buffer against water-borne diseases. However, in this case, the dosing will be greatly reduced when compared to the conventional system.

No description available.

No description available.

No description available.

In axial electrofiltration, a DC electric field is imposed between a rotating inner cylinder and a stationary outer cylinder giving rise to four mechanisms which act to minimize solute accumulation at the filter surface: turbulence, centrifugal force, electrophoresis and shear stress which removes solute aggregates. / Four dynamic membranes, Zr(IV) oxide, calcium oleate, poly-2-vinylpyridine and cadmium sulfide, were used to filter bovine serum albumin (BSA) in a disodium phosphate solution at pH = 8 and Prussian blue in distilled water. Prussian blue is a particle of 0.01(mu)m diameter with a zeta potential of -41mV while BSA is a macromolecule of 69,000 molecular weight, a Stokes-Einstein radius of 0.0038(mu)m and a zeta potential of -23.3mV at pH = 8. For BSA, the flux declined with time while the rejection increased. Filtrate fluxes increased with rotation rate and electric field and declined with concentration for both feeds. The flux declined beyond N = 2000rpm and was constant above C(,0) = 5.0wt%. For Prussian blue, the rejection was greater than 90% at all levels of E, N and C(,0). For BSA, the rejection increased with rotation rate and declined with concentration. The BSA rejection declined above N = 2000rpm and was constant beyond C(,0) = 0.5wt%. / A mathematical model was derived to predict the time variation of filtrate flux and a rejection model was used to predict the effect of surface concentration on BSA rejection.

No description available.

No description available.