Biodiesel production from rice straw and restaurant waste employing black soldier fly assisted by microbes

Biodiesel has become attractive as an alternative renewable fuel, but its large-scale production has been restricted because of the high cost of feedstock. Therefore, alternative feedstock is urgently needed to enable biodiesel production from cheap raw materials. Toward this goal, a co-conversion process using BSFL (black soldier fly larvae) and microbes (Rid-X) was established to convert rice straw and RSW (restaurant solid waste) into the larval grease of black soldier fly. In this study, about 43.8 g biodiesel was produced from 2000 BSFL grown on 1000 g mixed feed of rice straw (30%) and RSW (70%) within 10 days. About 65.5% of cellulose, 56.3% of hemicellulose, 8.8% of the lignin, 91.6% of protein and 71.6% of lipid in the feed were digested and utilized for insect biomass accumulation with the aid of Rid-X. The results showed that grease from BSFL fed on rice straw and RSW was suitable for biodiesel and most of the fuel properties were corresponding to the requirements of the standard EN 14214. The new alternative method was introduced to produce biodiesel from lignocellulose abundant materials by insect and microbes, partly bypassing the complex pretreatment of lignocellulose that needed by other biofuel technologies.