Assessment of Physical and Combustion Properties of Fecal Sludge-Derived Char Briquettes Bonded by Waste Papers, Cassava, and Banana Peels

Innovative approaches using biomass and waste for briquette production are needed to address energy deficiencies in household cooking and heating. Fecal sludge (FS) can serve as a feedstock for briquette production. However, the physical and chemical qualities of the briquettes produced using FS and different binding materials are still inadequate. This article examines the physical and combustion properties of carbonized FS bio-briquettes made using five different binders, namely, waste paper (WP), cooked banana peels (CB), non-cooked banana peels (NB), cooked cassava peels (CC), and non-cooked cassava peels (NC). Bio-briquettes were made at various binder ratios (0%, 25%, 50%, and 75%) using a locally fabricated manual pressing machine. Overall, the study discovered that all bio-briquettes fabricated can be utilized for heating and cooking; however, the type and quantity of binders employed influence their quality. The study concluded that FS bio-briquettes blended with 75% WP binder were the best, outperforming others in many tests including drying rates (6 days), physical tests (passed shattering [95%], water boiling [240 s], and tumbling tests [100%]), and burning/thermal efficiency (19.23 MJ/kg). The study suggests further research to be conducted on combining FS with other biomass feedstocks to decrease volatile matter and emissions in bio-briquettes made with FS and non-carbonized binders.