Aquatic worms grown on biosolids: Biomass composition and potential applications

• Published in: Bioresource technology Vol. 101; no. 2; pp. 804 - 811
• Main Authors: Elissen, H.J.H., Mulder, W.J., Hendrickx, T.L.G., Elbersen, H.W., Beelen, B., Temmink, H., Buisman, C.J.N.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2010; [New York, NY]: Elsevier Ltd; Elsevier
• Subjects: activated sludge; amino acid composition; Animals; Applied sciences; Aquatic worms; bioaccumulation; biodiesel production; Biological and medical sciences; Biological treatment of sewage sludges and wastes; Biomass; Biomass re-use and applications; bioremediation; biosolids; Biotechnology; cadmium; carbohydrate composition; chemical composition; diet; earthworms; Electrophoresis, Polyacrylamide Gel; Environment and pollution; Environmental Pollutants - metabolism; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; heavy metals; Industrial applications and implications. Economical aspects; lipids; Lumbriculus variegatus; lumbriculus-variegatus oligochaeta; Oligochaeta - growth & development; Oligochaeta - metabolism; Pollution; protein content; sediment; Sewage; sewage-sludge; toxicity; Waste activated sludge; Wastes; wastewater treatment; Biomass re-use and applications; Aquatic worms; Waste activated sludge; Lumbriculus variegatus; Activated sludge; Biomass; Wastes; Invertebrata; Sewage sludge; Annelida; Oligochaeta
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2009.08.060

The increasing production of biological waste sludge from wastewater treatment plants is a problem, because stricter legislation inhibits the use of traditional disposal methods. The use of the aquatic worm
Lumbriculus variegatus can minimise sludge production. Because the worms can feed and grow on this waste sludge, valuable compounds that are present in the sludge can be recovered by the worms. This paper describes a systematic approach for finding possible applications of the produced biomass. The worm biomass mainly consists of protein and smaller fractions of fat, sugar and ash. It also contains low concentrations of heavy metals. The potential produced amount is relatively small, compared to other waste streams, and is produced decentrally. Therefore, the most promising applications are specific components of the biomass, for example specific amino acids or fatty acids. However, until the process is optimized and there is a stable supply of worms, the focus should be on simple applications, later on followed by specific applications, depending on the market demand. Worm biomass grown on clean sludges has a broader application potential, for example as consumption fish feed.