Wastewater sludge to energy production.A review

摘要

Global economic and social development involves increasing demands for water use for various purposes:domestic,public,industrial.Wastewater treatment in these processes results in increasing volumes of sewage sludge.The elimination of this sludge is a permanent concern at global level because of the dangers to the environment,consisting of the high content of organic pollutants,toxic and heavy metals.However,a significant amount of renewable energy can be recovered from sludge from sewage treatment,with several paths being possible:anaerobic digestion,combustion and co-combustion,pyrolysis,gasification.Each of these pathways is characterized by advantages and disadvantages,benefits and technological limitations.This paper proposes a review of current conversion methods and technologies for energy recovery from sewage sludge,anaerobic digestion,incineration and co-combustion especially.Processes present in current literature and practice are described,resulting in the influence of the properties of sludge fuels and their impact on the energy recovery process when these fuels are used in combustion plants.There are also scientific researchers conducted to improve operational and environmental performance and cost competitiveness.