A significant nutrient load can be generated internally by publicly owned treatment works (POTWs). These nutrients can be found in the reject water, also known as side streams, of many municipal wastewater and sewage sludge treatment processes. These side streams include the reject stream from membranes, supernatant liquid from sludge digesters, and the centrate/filtrate return stream from sewa...

Sludge Treatment Reed Beds (STRBs) are widely used in Northern Europe to dewater and mineralize surplus sludge from activated sludge systems used to treat urban domestic sewage. STRBs are low-technology, energy-efficient, and do not require addition of chemicals. They dewater and stabilize the sludge and produce a final product that can be safely used as a fertilizer for agricultural crops. Lon...

Carbonization is a newly developed process that converts sewage sludge to biocoal, a type of solid biomass that can partially substitute for coal during power generation. This study presents an assessment of the environmental effects of various sewage sludge treatment processes, including carbonization, direct landfills, co-incineration with municipal solid waste, and mono-incineration in Taiwa...

The purpose of this paper is an experimental and model assisted investigation of the capabilities of a dewatering system for sewage sludge for decentralised sites. Laboratory and field tests are performed with different initial conditions and the influences of filter medium, initial height, initial total suspended solids, temperature and relative humidity are discussed. The experimental work sh...

The management of wastewater sludge, now often referred to as biosolids, accounts for a major portion of the cost of the wastewater treatment process and represents significant technical challenges. In many wastewater treatment facilities, the bottleneck of the sludge handling system is the dewatering operation. Advanced sludge treatment (AST) processes have been developed in order to improve s...

The composition of municipal wastewater and sewage sludge reflects the use and proliferation of elements and contaminants within society. In Sweden, official statistics show that concentrations of toxic metals in municipal sewage sludge have steadily decreased, by up to 90 %, since the 1970s, due to environmental programmes and statutory limits on metals in sludge and soil. Results from long-te...

The composting of thermal-hydrolyzed kitchen biogas residue, either with or without sewage sludge, was compared in this study. The addition of sewage sludge increased and prolonged the temperature to a sufficient level that met the requirements for aerobic composting. Moreover, after mixing the compost materials, oxygen, ammonia, and carbon dioxide levels reverted to those typical of aerobic co...

In order to enhance mechanical dewatering, conditioning polymers are used to flocculate sewage sludge. These polymers modify floc structure, which has an impact on dewatering efficiency. However, fundamental aspects of those processes are incompletely understood, particularly the way that flocs are structurally organized and how this may relate to their mechanical and dewatering properties. Thu...