TECHNO-COMMERCIAL COMPARISON OF MEMBRANE BIO-REACTOR WITH ACTIVATED SLUDGE PROCESS AND MOVING BED BIO-FILM REACTOR

Abstract

The wastewater from industries varies so greatly in both flow and pollutional strength. In general, industrial wastewaters may contain suspended, colloidal and dissolved solids. In addition, they may be either excessively acid or alkaline and may contain high or low concentrations of coloured matter. These wastage may contain inert, organic or toxic materials and possibly pathogenic bacteria. These wastes may be discharged into the sewer system provided they have no adverse effect on treatment efficiency or undesirable effects on the sewer system. It may be necessary to pretreat the wastes prior to release to the municipal system or it is necessary to a fully treatment when the wastes will be discharged directly to surface or ground waters. The technologies discussed in the project are Membrane Bio-reactor (MBR), Activated Sludge Process (ASP) and Moving Bed Bio-film Reactor (MBBR). Membrane Bio-reactor (MBR) is a wastewater treatment technology that offers many advantages including excellent effluent quality, stable operation performance, a small footprint, reduction of excess sludge production, reuse of effluent, reduction of risk substances and so on. When one takes into consideration that fresh water serves as a precious resource for human brings, the ability to reuse treated water is one of the biggest advantages of using MBR technology. The activated sludge process (ASP), found in the wastewater treatment plants, consists basically of a biological reactor followed by a sedimentation tank, which has one inlet and two outlets. The purpose of the ASP is to reduce organic material and dissolved nutrients (substrate) in the incoming wastewater by means of activated sludge (microorganisms). The major part of the discharged flow thrugh the bottom outlet of the sedimentation tank is re-circulated to the reactor, so that the biomass is reused. The moving bed bio-reactor (MBBR) technology is an attached growth biological treatment process based on a continuously operating, non-clogging bio-film reactor with the low head loss, a hig specific bio-film surface area, and no requirement for backwashing. Moving bed technology presents several operational advantages, compared to other conventional biological treatments.