Scaling-up of an up-flow anaerobic sludge blanket incorporated with a bio-filter liner system for treating kitchen wastes

Abstract

A bottom biofilter liner incorporated to an Up-flow Anaerobic Sludge Blanket Reactor (UASBR) was designed, developed and evaluated for food wastes for 47 days as a semi-batch setup with intermittent up-flow circulation (very infrequent) to simulate the start-up. This study was conducted to scale-up already developed UASBR. In the mineralization process, the surface area at the bottom of the reactor is the most critical parameter. Thus, it has been found that total dissolved solids (TDS) of bottom, middle and top strata seem to follow first order rate reactions. The TDS was divided by the feeding that took place at different times to give a unit production of TDS at time t. The average unit value of the bottom strata was then divided by the lowest experimental TDS value, thus yielding a ratio equating the two areas of desired to that of the experimental value. Therefore, a diameter (or area) could be found for any loading rate. The height of the reactor was found by considering ratios of the volumes to that of the predicted maximum TDS concentration obtained from the learning curve of the first order reactions and the maximum experimental value. The total height of reactor is 3.4 m, which is optimum for kitchen wastes, would remain constant for different loading rates. A prototype would be constructed and performance would be evaluated to reconfirm the hypothesis that a biofilter liner system is effective in reducing inhibitions often encountered in UASB reactors