Agricultural and non-agricultural directions of bio-based sewage sludge valorization by chemical conditioning.

This literature review outlines the most important-agricultural and non-agricultural-types of sewage sludge management. The potential of waste sludge protein hydrolysates obtained by chemical sludge conditioning was reported. The discussed areas include acidic and alkaline hydrolysis, lime conditioning, polyelectrolyte dewatering and other supporting techniques such as ultrasounds, microwave or thermal methods.