Types of Sludge and Their Properties

Different kinds of sludge are described in detail, ranging from unstabilized biological sludge via aerated sludge to digested sludge. Parameters for evaluation of quality of stabilization are presented with a special focus on digested sludge. Also, sludge resulting from biological phosphorous removal from wastewater and from advanced digestion processes with hydrolysis are mentioned. Industrial sludge from paper mills is briefly treated. Sludge features and ingredients are tabulated together with their effects on drying and incineration. Sticking of waste activated sludge and calorific values of different kind of sludge are tabulated.