Biological Treatment of Condensate from Aerobic Digestion of Biodegradable Waste:A German Example

摘要

Separation of household waste into recyclable,biodegradable,and nonbiodegradable components is required in Germany.Aerobic digestion of the biodegradable component can further minimize the waste volume.During aerobic digestion a hot humid exhaust stream,containing volatile organic and other low molecular weight compounds,is produced.Cooling this stream produces up to 350 L of condensate per ton of biodegradable feed material.Efficient treatment of this condensate is essential for a practical aerobic digestion process.Reuse of the condensate could lead to improved process economics.In this paper,condensate treatment by biological degradation using intermittent sparging has been investigated.An inorganic ultrafil-tration membrane was used to separate the biomass from the treated water.It is shown that this one-step intermittent nitrification/'denitrification process may be used to reduce COD,total nitrogen,and ammonia nitrogen concentrations to acceptable values for direct discharge of the treated water into rivers.