EFFECT OF FLOW VELOCITY ON UASB REACTOR

Abstract

The biochemical parameters and fluid flow characteristics control the design and operatiOn of a biological wastewater treatment unit. In the present thesis the impact of fluid flow characteristics on design and operation of an upflow anaerobic sludge blanket (UASB) has been investigated. The wastewater entering UASB reactor at the bottom passes through the bed and blanket of bacterial biomass and gas solid separator. The channeling in the bed can be minimized by taking a suitable combination of bed height and liquid upflow velocity. The solid concentration in the blanket and wastewater upflow velocity. Experimental observations have shown decreasing solid concentration profile along the reactor height. To retain the sludge in to the reactor the solid concentration at the top of the blanket should commensurate with the performance and design of the GSS. Bed height determination has mathematically been approached. Design Blanket height has so far been forced arbitrarily. The objective of the work presented here is to mathematically simulate sludge distribution profile in the blanket of the reactor at different liquid upflow velocity and gas flow rates. The computed values have been shown to well represent experimental observations obtained from a range of operational conditions. The bed requirement is correlated to cOD assimilation and gas production. In another analysis the solid wash out necessary condition for sludge retention of blanket height determination has been approached. The solid washout for a laboratory reactor has been quantified.