BEHAVIOR AND PERFORMANCE OF THE MOVING BED BIOFILM REACTOR (MBBR) PROCESS FOR ORGANIC MATTER AND NITROGEN REMOVAL

Abstract

The MBBR process is a recent development technology that incorporates the best characteristic of processes with growth of biomass in suspension and attached biomass (biofilm). The technology was initially developed in Norway, to improve the performance the acting and/or to increase the capacity of plants of already existing wastewater treatment plants, mainly composed by activated sludge, with the minimum of physical expansion of the biological reactor and, consequently, accomplishment of engineering civil works. Inside the biological reactor of the MBBR process, carries with high Specific Superficial Area are kept in suspension. The mixing promoted by the aeration system exposes the carries to the liquid mass in suspension and, consequently, the microorganisms are kept attached and also in suspension. Therefore, in a same volume of the biological reactor volume it is possible to maintain a larger amount of biomass, thereby adding a larger amount of substratum to biodegradation. The control parameters are the same applied to the activated sludge process. This technology is under investigation at the Experimental Center of Environmental Sanitation of the Federal University of Rio de Janeiro (CESA-UFRJ) in an experimental unit, with a population equivalent to 500 inhabitants. Thus, this paper... presents and discusses some concepts related to technology and also exposes the results achieved after investigate the MBBR under variations in its operating conditions. The carries used, containing 600 m²/ m³ Specific Surface Area, were introduced into the biological reactor in 20% of volume.

Key words: Attached Biomass, Domestic Wastewater Treatment, Moving Bed Biofilm Reactor, Organic Matter and Nitrogen Removal.