Methane production from insect, worm and mushroom waste streams and combinations

Abstract

In literature, the synergistic effect of several substrates on feedstocks for anaerobic digestion/methane production is described for several substrates. Champost from mushroom production, vermicompost from worm composting/vermiculture and BSF (black soldier fly) larvae frass from insect production were therefore tested for this report for their synergistic effect. It was found that insect frass had a very high biogas/methane production as a single substrate. Addition of the frass led to a concentration dependent biogas production in mixtures with 'old' digestate higher than was expected based on the results of the single substrates. Champost resulted in some biogas production but from vermicompost hardly any biogas could be produced. Also, no synergistic or concentration effects could be noted from the latter two.

Combined digestion of insect frass and cow manure for biogas production

“…Table 4 shows biogas productions from several reference substrates. The biogas production values differ between the measurements of this report and Elissen et al (2019). The dry matter percentage of the insect frass varies between 63 and 83 %, where the non-hygienised is the highest.…”

“…According to Bulak et al (2020) 379.0 nm³/ton DM for mealworm frass, 389.5 nm³/ton DM for cricket frass and 351.4 nm³/ton DM frass for Hermetia illucens larvea frass (black soldier fly). In previous research a possible synergistic effect on the biogas production was found using a combination of digestate and insect frass from Hermetia illucens larvae (Elissen et al, 2019). Xie et al(2017a) also found a synergistic effect on specific methane yield when mixing primary sludge with food waste.…”

“…In an experiment described by Elissen et al (2019) on anaerobic digestion of black soldier fly (BSF, Hermetia illucens) larvae frass, the frass had been previously hygienised due to Dutch law. However, when the frass would stay on the same premises this hygienisation step may not be necessary.…”

“…The question is whether adding Hermetia illucens larvae frass leads to an improvement in methane yield. In the experiment described by Elissen et al (2019) the insect frass was previously hygienised due to Dutch law (at least an hour at 70°C), but when the frass stays on the same premises this does not seem necessary. Within this research the effect of adding hygienised and non-hygienised insect frass to cattle slurry is investigated.…”

Growth of fungi on alternative substrates and fungal pre-treatment for biogas production

“…In general, (average) biogas productions from the different substrates with or without fungal pretreatment did not differ to a large extent and were relatively low (35-73 nm3 biogas per ton product) except for that from insect frass (274 nm 3 biogas per ton product): It was high and similar to that found in a previous experiment(Elissen et al, 2019). When comparing the numbers to other data, | Report WPR-832…”