A new reactor concept for sludge reduction using aquatic worms

• Published in: Water research (Oxford) Vol. 40; no. 20; pp. 3713 - 3718
• Main Authors: Elissen, Hellen J.H., Hendrickx, Tim L.G., Temmink, Hardy, Buisman, Cees J.N.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-12-2006; Elsevier Science
• Subjects: activated sludge; Activated sludge reduction; Animals; Applied sciences; aquatic organisms; Aquatic worms; biological treatment; Bioreactors; Exact sciences and technology; Feces; Lumbriculus variegatus; Oligochaeta - metabolism; oligochaete; Other industrial wastes. Sewage sludge; Pollution; pollution control; Predation reactor; Sewage; Waste Disposal, Fluid - methods; Wastes; wastewater treatment; water pollution; Water treatment and pollution; Netherlands; Europe; Aquatic worms; Activated sludge reduction; Lumbriculus variegatus; Predation reactor; Activated sludge; Water treatment; Heat treatment; Batchwise; Incineration; Waste treatment; Activated sludge reduction Predation reactor Aquatic worms Lumbriculus variegatus; Biological treatment; Waste water purification; Reactor; Waste water; Biological purification
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2006.08.029

Biological waste water treatment results in the production of waste sludge. The final treatment option in The Netherlands for this waste sludge is usually incineration. A biological approach to reduce the amount of waste sludge is through predation by aquatic worms. In this paper we test the applicability of a new reactor concept for sludge reduction by the aquatic worm
Lumbriculus variegatus. In this reactor concept the worms are immobilized in a carrier material. In sequencing batch experiments, the sludge breakdown in the predation reactor is compared to sludge breakdown in a blank reactor (i.e. without worms). Predation by the worms results in a distinct sludge reduction, which is almost three times higher than in the blank experiment. The worm faeces that are produced after sludge predation have a sludge volume index (SVI) that is approximately half that of the initial waste sludge. Due to the configuration of the predation reactor, waste sludge, worm faeces and worms are separated, which is beneficial to further processing. The obtained results show that the proposed reactor concept has a high potential for use in large-scale sludge processing.