Respirometric activity of activated sludge and biofilm in IFAS-MBBR system

Abstract

The aim of the presented study was: a) assessment of activity of microorganisms developed in form of activated sludge and biofilm, b) indirect assessment of the role of analyzed biocoenoses in removal of organic compounds in hybrid reactor with moving bed. Oxygen uptake rate tests (OUR) have been used, and obtained results were presented as volumetric activity (Vo2v, expressed in mg O2/L · h) and mass activity (Vo2m expressed as mg O2/g VTS · h). Tests were conducted for three different variants, in which, as the biomass: 1) biofilm was used, 2) activated sludge was used, 3) biofilm and activated sludge were used. The biomass was collected from aerobic reactor from a wastewater treatment plant working in IFAS-MBBR system. The highest volumetric activity was observed for variant with biofilm and activated sludge, and the lowest for variant with biofilm only. Nonetheless, the highest value of oxygen uptake rate related to total volatile solids was observed for variant with biofilm and the lowest for activated sludge. Obtained results suggest, that during this research, at the wastewater treatment plant, the main role in removal of organic pollutants played the biomass developed in form of activated sludge.