Thermophilic anaerobic digestion and pasteurisation. Practical experience from Danish wastewater treatment plants

摘要: Increasing sludge disposal costs have highly intensified the interest in reducing quantities from Danish wastewater treatment plants. By upgrading existing mesophilic digesters to thermophilic temperature range, retention time can be halved and many designed only for primary will sufficient capacity treat also biological excess sludge. At moment, eight full-scale are operation Denmark five under construction. This paper describes experience gained digestion of as well a mixture Thermophilic has proven good stable process solids reduction pathogen removal. The digested dewatered high content thereby quantity reduced by 30-40% depending on type plant. A drawback is that polymer dewatering may increased type.