Composting

Composting is used for both sludge stabilization and final disposal. In During composting, organic material undergoes biological degradation, resulting within a 20 to 30 per cent reduction of volatile solids. Whole micro-organisms are also destroyed because of the rise in temperature of the compost. Composting involves the following operations:

(a)        Mixing dewatered sludge along with a bulking agent.

(b)       Aerating the compost pile through mechanical turning or the addition of air.

(c)        Recovery of the bulking agent.

(d)       Additional curing and storage.

(e)        Final disposal.

The resulting end product is stable and might be used as a soil conditioner in agricultural applications. Aerobic composting is more commonly used than anaerobic composting. The three main types of aerobic composting systems are the static aerated pile, windrow and in-vessel systems.