Removal of nitrates from ground water by a hybrid process of biological denitrification and microfiltration membrane

Removal of nitrates from ground water in a hybrid process of biological den itrification and microfiltration is discussed. The most favourable paramete rs for a culture of denitrifying bacteria with respect to organic carbon/ni trate nitrogen (C/N) ratio and nitrate loading have been determined. A capi llary module was selected on the basis of the amount of biomass retained du ring microfiltration. The optimum operational parameters of microfiltration on the selected membrane module were determined. The installation used for denitrification consisted of a bioreactor and a membrane module made of ca pillary fibres. This was fed continuously for several months with a fluid m edium containing organic carbon (methanol), nitrates and biogenic elements. (C) 2001 Elsevier Science Ltd. All rights reserved.