Anaerobic thermophilic digestion of manure at different ammonia loads: Effect of temperature

• Published in: Water research (Oxford) Vol. 28; no. 3; pp. 727 - 731
• Main Authors: Angelidaki, I, Ahring, B.K
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1994; Elsevier Science
• Subjects: Agriculture, rearing and food industries wastes; ammonia; anaerobic; Applied sciences; biogas; Exact sciences and technology; Pollution; temperature; Wastes; temperature; ammonia; anaerobic; biogas; Ammonia; Temperature; Medium effect; Waste treatment; Biogas; Agricultural waste; Farmyard manure; Anaerobic digestion
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/0043-1354(94)90153-8

The effect of temperature in the range of 40–64°C, on thermophilic anaerobic digestion of cattle manure with two different ammonia concentrations (2.5 and 6.0 g-N/l) was investigated in continuouslyfed lab-scale reactors: the higher ammonia concentration reduced the maximum tolerable temperature. Poor process performance was observed when the combination of temperature and ammonia loading resulted in a calculated concentration of unionized ammonia (NH 3) exceeding approx. 0.7 g-N/l, at the applied retention time of 15 days. When the ammonia load was high, reduction of the temperature below 55°C resulted in an increase of the biogas yield and better process stability, indicated by a lowering of the concentration of volatile fatty acids in the effluent.