The role of anaerobic digestion of domestic sewage in closing the water and nutrient cycle at community level

Decentralised sewage treatment is more and more considered to be a sustainable way of waste(water) treatment. Three different options for the on-site treatment of sewage in combination with VFY (Vegetable, Fruit and Yard waste) with anaerobic treatment as a central technique are presented. The collection system and therewith the composition and concentration of the sewage will determine the type of anaerobic technology and the process conditions to be applied. Model calculations are made for determining the HRT to be applied in a UASB system at an obliged SRT at a certain temperature.