Stabilisasi Sludge dari Instalasi Pengolahan Air Limbah (IPAL) Menggunakan Starter Bakteri Indigenous pada Aerobic Sludge Digester

Abstract

Sludge stabilization is degradation process for the organic components into simpler compounds, and to eliminate toxic compounds and volatile compounds that cause the unpleasant smell by activities of some microorganisms. Proteolytic and cellulolytic bacteria are predominant and indigenous microorganisms play an important role in the degradation of organic components on activated sludge. The aim of this study was to stabilize sludge that can be used for fertilizer production by using various types of indigenous bacterial isolated from industrial biological wastewater as liquid starter, as well as determine the effect of aeration time (0, 5, 10, 15, 20, 25, and 30 days) on the characteristics of sludge stabilization. The research investigated the effect of starter addition, from indigenous bacteria isolates, as (1) proteolytic bacteria, (2) cellulolytic bacteria, and (3) no starter addition as control. The process degradation by indigenous microorganisms and capable to convert nitrogen compounds such as ammonium to nitrate. The result showed that all bacteria starters have high capability to accelerate the degradation of organic compound, but not significantly in the stabilization procced periode. The addition of proteolytic bacteria increased the breakdown of protein compound into ammonium, while cellulolytic bacteria increasing the formation of total suspended solids (TSS), volatile suspended solids (VSS), total COD, and soluble COD compared to the control. The addition of cellulolytic bacteria showed the higest value of C/N ratio (9.17) compared to the others (7.12 - 8.97).