ABSTRACT
Lime stabilization has been used for centuries to reduce the odor generation and pathogen levels of biological matter. It is a simple and effective method of sludge processing that requires little specialized equipment. When lime is mixed with dewatered sludge, microorganisms involved in the decomposition of the sludge and pathogens are inhibited or destroyed. Lime is commercially available in two forms: quicklime and hydrated lime. Three lime-sludge mixing systems have been developed. Liquid sludge can be mixed with lime and land applied by tank trucks, it can be mechanically dewatered after the addition of lime, or lime can be mixed with sludge cake that has been dewatered to about 20% solids. The effectiveness of lime stabilization chemistry on sludge cake has inspired the development of some variations of the lime stabilization process, including lime pasteurization with supplemental heat and chemical fixation.
