Evaluate the energy management of waste water treatment plant using WESim model

ABSTRACT At present, wastewater treatment is based on energy demanding unit operations. Treated wastewater then is discharged to water bodies by either gravity or pumping or undergoes additional processing and is reused. Many factors will affect the energy intensity of water and wastewater treatment technologies in the future. First of all, climate change will affect freshwater availability and, hence, water supply, its quality and demand, and will probably increase supply needs and boost research for new, and less energy demanding, treatment options. In addition, the increase of world’s population, different water use patterns, technology, and price will affect water demand. Finally, stricter water quality regulations on emerging micropollutants may require more energy-intensive treatment technologies. At present, rising energy costs and limits on greenhouse gas emissions will require new technological and operational solutions. These trends highlight the need for a clear and consistent methodology for evaluating the energy and greenhouse gas implications of water management decisions. The Water-Energy Simulator (WESim) is a free-software, easy-to-use, analytical tool for evaluating the energy and greenhouse gas implications of wastewater management decisions. This work describes a simple application of this model to a real wastewater treatment plant located in Northern Italy. The model showed to be a simple and effective tool to easily estimate the improvement in green-house gases emissions when implementing photovoltaic systems and anaerobic digestion of sludge in the plant.