Assessment of thermochemical technologies for wastewater sludge-to-energy: An advance MCDM model

In the recent past the tremendous growth of populace, industrial development, and urbanization adds to the inevitable production of wastewater sludge (WWS), needing more sludge disposal and renewable energy generation technologies. The thermochemical technologies namely combustion/or incineration, pyrolysis, and gasification have a great prospect of energy recovery with the possibility to be feasible when considering costs and efficiencies. This research paper seeks an investigation on the selection of the finest or feasible thermochemical conversion technology to treat, dispose and generate gas energy in turn heat and electric power. This can be achieved through an advance multi-criteria decision making (MCDM) model using analytical hierarchy process (AHP) and the technique for order of preference by similarity to ideal solution (TOPSIS) to form a AHP-TOPSIS focused on technical and economic criteria. Results show that combustion or/incineration is the most viable technology due to its ability to lessens enormous sludge volume, recuperate energy, demolish pollutants. Gasification is favourable due to benefits such as high efficiency, continual volumetrically heating, and fast thermal reaction. With regards to pyrolysis conversion technology, this process is regarded among of the most feasible thermochemical technologies with zero-waste production, it can gas recover energy and materials such as biogas, biochar, water, tar, etc. With the aforesaid advance thermochemical technologies, the sludge treatment and energy conversion difficulties are foreseen to be limited or lessened. •The conversion of wastewater sludge or sewage sludge to energy.•Thermochemical energy conversion techniques.•Multi-Criteria Decision Making.•Analytical Hierarchy Process (AHP).•Technique for Order of Preference by Similarity to Ideal Solution (AHP).