53 / 2021-06-30 09:02:34

Utilization of food waste digestate for black soldier fly larvae cultivation: a promising choice for digestate disposal

Food waste; black soldier fly larvae; anaerobic digestate; biogas; insect biomass.

Anaerobic digestion (AD) is widely used in food waste (FW) disposal, which generates a large amount of high salinity digestate. This paper studied the utilization of AD digestates to grow black soldier fly larvae (BSFL) as a digestate treatment method. Results showed that both digestates from hydrogen and methane fermentations were rich in protein and lipid contents, which benefited the BSFL cultivation. The BSFL reared on digestates of hydrogen fermentation and methane fermentation performed better in pre-pupal weight (19.09% and 41.09% higher, respectively), body length (3.49% and 18.34% higher, respectively) and crude protein contents (7.85% and 39.05% higher, respectively) than those of raw food waste. Organic matter reduction of digestates between 40.97 and 46.07% were achieved during BSFL cultivation. Using BSFL to treat AD digestate not only provides a digestate disposal approach, but also produces insect biomass and organic fertilizer as value-added byproducts.