Ensiling of Invasive Elodea sp., a Novel Aquatic Biomass Feedstock for the Sustainable Biogas Production: Effects of Wheat Straw and Silage Additives on Silage Quality and Methane Production

Abstract

This study investigates for the first time the invasive Elodea sp. as a novel aquatic biomass feedstock for the production of renewable energy in the form of methane (CH 4 ) via anaerobic digestion (AD). For a commercial AD, to overcome the issue of biomass seasonality and the fact that aquatic biomass exhibits high moistures that complicate storage and hence biomass and CH 4 conservation, we propose the ensiling of Elodea biomass as an effective preservation method that provides a consistent, reliable, and predictable supply. The effects of inclusion of wheat straw to ensiled Elodea (Elodea and mixture silages) and silage additives (added alone or in combination) on silage quality and CH 4 production were evaluated. Results revealed that the inclusion of wheat straw played a key role in the Elodea biomass and CH 4 preservation and was responsible for any apparent effects of silage additives. Specifically, increased silage quality as evidenced by higher lactic acid (LA) and lower pH correlated strongly with inclusion of wheat straw. In addition, wheat straw impacted CH 4 production through the preservation of Elodea biomass. Toward the utilization of this invasive aquatic biomass, ensiling Elodea biomass only with wheat straw suggests a significant alternative and is perhaps crucial for its efficient preservation and CH 4 production.

Medium-chain carboxylates production from plant waste: kinetic study and effect of an enriched microbiome

“…The production yields and selectivities of acetate, propionate, butyrate and caproate were significantly different (p < 0.05) after 21 days (Table 2 ), probably due to the different physico-chemical properties of the individual substrates, in particular the contents of the electron donors lactate and ethanol (Table 1 ). Also, the proportion of lignocellulose and thus the accessibility and share of fermentable components such as hemicellulose varied between the different substrates (hemicellulose contents: 4.66%TS [ 34 ], 12.6%TS [ 35 ], 10.78%TS [ 13 ], and 28.3%TS [ 34 ] in Elodea , cassava leaves, sugar beet leaves, and wheat straw, respectively).…”