| dc.description.abstract | Black Soldier Fly Larva (BSFL) composting presents a sustainable approach to reclaiming nutrients from Fecal Sludge Cake (FSC) generated during Fecal Sludge (FS) treatment. This study investigated the potential of BSFL composting for resource recovery from FSC while evaluating its impact on greenhouse gas (GHG) emissions. Treatments used in the study include (T0, (100%FSC), T2 (75%FSC: 25%CM), T5 (75%FSC: 25%FVW), T3 (65%FSC: 25%CM), T6 (65%FSC: 25%FVW), T4 (55%FSC: 45%CM), T7 (55%FSC: 45%FVW), T8 (100%FVW), T9 (100%CM). The moisture content decreased in all treatments, ranging from 17.23% to 45.23% in T8 and T9, respectively. Total Volatile Solids (TVS) also decreased in the final frass compared to initial samples, with the highest reduction in T2 (11.01%) and the least in T0 (5.25%). Nitrogen content (% N) consistently increased across all samples, with the highest percentage increase in T9 (0.54%) and the lowest in T7 (0.02%). While T9 experienced a slight decrease (3.54%) in total phosphorus content, all other treatments showed an increase, with the highest in T8 (47.98%). Potassium content increased in all treatments, with the highest increase in T8 (44.5%). Organic carbon (%OC) decreased across all samples, with the greatest reduction in T2 (29.82%). The largest decrease in the C/N ratio occurred in T3 (60.99%), with the smallest in T6 (19.45%). Silicon content increased for all treatments, with the highest in T8 (53.76%). Iron (Fe) content also increased in different treatments, with the highest in T9 (32.25%). Other heavy metals exhibited a decrease in concentration across all treatments, such as molybdenum (MO) in T0, copper in T5, zinc (Zn) in T9, and lead (Pb) in T8. Larvae from various treatments showed varying levels of metal accumulation, with the highest accumulations observed in Cu in T5, MO in T8, Pb in T7, Zn in T0, and Fe in T7. In terms of larval development, T8 yielded the highest weights, ranging from 210-212 mg, while T9 and T4 had the lowest weights, ranging from 6-12.4 mg and 12-14.6 mg, respectively. Pathogen reduction was observed, with the highest reduction in T8 (3.23logCFU/g) and least reduction in T6 (0.45logCFU/g). For Staphylococcus aureus, T4 (1.29logCFU/g) was the highest reduction, with T8 (0.102logCFU/g) as the least reduction. The highest carbon dioxide (CO2) emission factor was observed in T8 registering an astonishing 15,302.16 g/kg, while T0 was the lowest emitter, with 326.21 g/kg. Treatments using Cattle Manure (CM) exhibited the lowest CO2 emissions. No traces of methane were detected in T3, while T6 showed higher methane emissions. The findings from this study provide valuable insights into the potential of BSFL composting for Fecal Sludge Cake resource recovery, emphasizing changes in nutrient profiles, heavy metals, larval development, pathogen reduction, and greenhouse gas emissions. These results underscore the importance of optimizing substrate compositions and microbial activities during BSFL composting to enhance sustainability and minimize environmental impact. | en_US |
