Extraction of heat and electric energy from wastewater sludge through a gasification process: DWSIM and COCO simulator approach

Due to the tremendous amount of wastewater sludge (WWS) generated by the high population, exacerbating sludge management issues related to treatment costs, stringent regulations, and ecological threats, there is a pressing need for advancements in current methods and the development of new innovative technologies to treat, dispose, and generate energy from WWS. This research seeks to assess the feasibility of extracting energy in the form of gas, heat, and electricity from WWS through a gasification process. Utilizing Daniel Wagner Simulator (DWSIM) and CAPE-OPEN (COCO) simulator software as analogous platforms has proven to be both viable and effective for facilitating the WWS gasification process. The optimal oxygen content of 13.49 wt. % (weight percentage) proves to be favorable, enhancing carbon oxidation in the sludge and leading to increased carbon dioxide production at 16.04 wt.%, thereby augmenting syngas compound generation. Temperature variations also impact syngas composition, with lower temperatures favoring hydrogen and reducing Carbon monoxide production, while higher temperatures (600–700 °C) increase syngas production. Approximately 102,887 kW of heat energy in the form of gas steam is recoverable within the system, which can be efficiently utilized for electricity generation through the use of a gas turbine. To ensure environmental preservation and resource optimization, it is imperative to incorporate gas cleaning processes such as multicyclones and wet scrubbers into the system.