Co-composting of Black Soldier Fly Frass (BSFF) with various organics additives for nutrient enhancement

Abstract

Black soldier fly frass is the nutrient-rich waste produced by black soldier fly larvae. This study aimed to enhance the frass by co-composting it with fish meal, bone meal, boiler ash, and sawdust. The co-composting process involved blending frass with the selected materials to achieve C:N ratio of 20, 25 and 30. After co-composting, characterization of total carbon, nitrogen, phosphorus and potassium contents and germination test were conducted. Fish meal increased nitrogen from 2.47 % to 3.10 %, bone meal improved phosphorus from 0.024 % to 0.042 %, and boiler ash raised potassium from 0.0023 % to 0.0039 %. Nevertheless, all the NPK source additives are required to balance and enhance all the nutrient level. Additionally, composts BSFF, fish meal, bone meal, and boiler ash, resulted in 100 % seed germination. The study demonstrates that co-composting frass with these materials effectively improves its nutrient content, providing a sustainable alternative for organic waste management and nutrient recycling.