Study of scanning electron microscopy, ultimate and proximate analysis of sewage sludge char and the use of RETScreen software

In this paper, we investigated different categories of sewage sludge (SS): dry SS after hydrothermal carbonization, before hydrothermal carbonization, plasma ash, ash after gasification with hydrothermal carbonization, and ash after gasification without hydrothermal carbonization. These five cases were studied. After proximate, ultimate, and scanning electron microscopy analysis, we found that sewage sludge before and after hydrothermal carbonization were the best of these five categories. The carbon content was higher and the sulfur content was lower in both cases than the other types of SS. A lower percentage of sulfur avoids corrosion. The percentage of ash was also low in both cases, which is more beneficial for plasma gasification as compared to the other types. The scanning electron microscopy showed that the hydro char surfaces were rougher and harder than the raw materials; moreover, it was found to be more porous than the raw material. The software program RETScreen is used for energy management. At its core, the tool is standardized and integrated clean energy project analysis software that can be employed worldwide for evaluating energy production, lifecycle costs, and reductions in greenhouse gas emissions for various energy-efficient and renewable energy technologies.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).