Is the dewatering of Palm Oil Mill Effluent (POME) feasible? Effect of temperature on POME's rheological properties and compressive behavior

The current treatment process of Palm Oil Mill Effluent (POME) has been a cause of concern over recent years as POME is known to cause greenhouse gas emission as well as water pollution. An alternative for POME treatment process optimization is to eliminate the conventional cooling ponds and introduce a dewatering device such as a thickener. The thickener will assist in the solid-liquid separation, removal of microbes and other impurities from the wastewater. The latter will contribute to making the anaerobic digesters used to treat POME more efficient by allowing a means of control on the digesters’ load. However, to be able to design and predict the performance of the thickener unit; essential rheological properties of the suspension have to be determined. The rheological characteristics and the compressive behavior of POME have not been studied previously nor has the implementation of such a dewatering device in the POME treatment process. This paper attempts to bridge the gap on the rheological characteristics, the compressive behavior and the effect of temperature on the rheological properties of POME through batch settling and batch filtration experiments. Data such as the compressive yield stress, the hindered settling function, and the diffusivity function for POME have been extracted and evaluated.