Investigation of Sludge in Anaerobic Sludge Bed Bioreactor

Abstract

The variation in granular sludge properties from various up-flow anaerobic sludge bed (UASB) reactors and the application of coffee grit as a physical model to characterize granular sludge were investigated in this study. The methods applied forevaluation were density measurements, settling profile and velocity, diameter measurements, total solids and volatile solids, total suspended solidsand volatile suspended solids and settleability of granular sludge. Experiments showed that coffee grits can be used as a physical model of granular sludge since it had similar characteristics especially in terms of settling and particle size while less so in terms of density but in a similar range. It was found that a weak correlation (R2 = 0.15) between density and settling velocity for coffee grits which might due to the non-uniformity in shape and particle size variation of coffee grits. For the granular sludge, higher density leads to a faster settling velocity and vice versa (R2 = 0.73). Moreover, it was found that Saugbrugs (new and old) properties were a slight changed with time, changes that may be good for process performance. Sample J (E-Convert old) had the highest size of granules (0.44 - 3.91 mm) and sample E (UASB – Econvert) had the lowest organic content which can be seen from its volatile to total solid ratio (0.55).