Effects of extra-cellular polymeric substances towards physical properties of biomass under magnetic field exposure

Abstract

Extra-cellular polymeric substances are responsible towards bioflocculation and settleability of sludge. This substances act as glue that holds the bioflocs to form larger aggregates by intervening both cells cohesion and adhesion. Different composition of this substances lead to different circumstances of sludge problem including bulking. Numerous studies have been conducted in optimizing the content of extra-cellular polymeric substances using various approaches. However, none of the approaches investigated on the use of magnetic field. Therefore, this study is aimed to investigate the effect of magnetic field on extra-cellular polymeric substances specifically its soluble-bound composition and its chemical constituents. Magnetic field of 88 mT was used in Reactor A, while Reactor B acted as control system. Results showed that Reactor A obtained mostly higher tightly bound extra-cellular polymeric substances compared to Reactor B in order of predominance: protein > polysaccharides > carbohydrates. These observations implied that magnetic field influenced the production of polymeric substances mainly its tightly bound constituent as well as protein and polysaccharides content. These productions were significant in improving bioflocculation and sludge settleability, thus minimizing potential occurrence of bulking.