This review paper present the MBBR and IFAS technology for urban river water purification including both conventional methods and new emerging technologies. The aim of this paper is to present the MBBR and IFAS technology as an alternative and successful method for treating different kinds of effluents under different condition. There are still current treatment technologies being researched and the outcomes maybe available in a while. The review also includes many relevant researches carried out at the laboratory and pilot scales. This review covers the important processes on MBBR and IFAS basic treatment process, affecting of carrier type and influent types. However, the research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. The research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. To this end, the most feasible technology could be the combination of advanced biological process (bioreactor systems) including MBBR and IFAS system.
The BioCellTM media are suitable for a moving bed biofilm reactor (MBBR) system to provide a self-shedding, self-regulating growth biofilm treatment process. The media can be used for MBBR treatment alone or as an integrated fixed membrane activated sludge (IFAS) process to enhance the effective capacity of existing activated sludge systems.
The BioCellTM medium used in MBBR media or IFAs is a continuous motion caused by air injection and agitator. Specific density of the media can be adjusted between 0.95-1.05 g/cm3 according to customer requirements. However, it should be considered that with the formation of biofilm on the surface of the medium, the actual density of the carrying media will increase.
The main characteristic of Moving Bed Biological Reactor (MBBR) configurations is that there is no sludge recycle from a secondary clarifier. MBBR is essentially a simple, once-through process, where all of the biological activity takes place on the biomass carriers. MBBR is usually followed by a solids separation system such as a secondary clarifier or DAF, in order to separate bio-solids produced in the process from the final effluent. The main advantage of MBBR is robust and simple reduction of soluble pollutants (soluble BOD or COD, NH4 +, etc.), with minimal process complexity, utilizing a significantly smaller footprint when compared to conventional aerobic treatment methods. MBBR is typically used for either high load industrial applications or for robust simple-to-operate municipal facilities.
The Integrated Fixed-film Activated Sludge (IFAS) process combines the advantages of conventional activated sludge with those of biofilm systems by combining the two technologies in a single reactor. Typically, an IFAS configuration will be similar to an activated sludge plant (utilizing all of the different process configurations such as MLE, UCT, Bardenpho, etc.), with biomass carriers introduced into carefully selected zones within the activated sludge process. This allows two distinct biological populations to act synergistically, with the MLSS degrading most of the organic load (BOD), and the biofilm creating a strongly nitrifying population for oxidation of the nitrogenous load (NH4+). IFAS is typically used to upgrade existing plants in order to enable extensive Nitrogen removal, or in designing new plants with significantly smaller footprints for extensive BOD and Nitrogen removal.
The diffuser is the special design for MBBR bio carrier media aeration system. The coarse-bubble design is employed to mix the suspended media evenly throughout the reactor while providing the mixing energy required to slough old biofilm from the internal surface area of the media and maintain the dissolved oxygen required to support the biological treatment process.
Mbbr sewage treatment can be applied for wastewater treatment in several plant configurations:
Industry nr. 1 produces about 18.000 m3d-1 wastewater with 2.500–3.500 mg/L COD. The wastewater treatment plant (picture 1) is made of a coarse screen, a primary settler, a fine screen, a cooling system, dosage of nutrients (nitrogen and phosphorus salts), a biological section and a final clarifloculation. The biological section has a first aerated pure biofilm MBBR filter media with 2.500 m3 volume filled with 40% NatrixTM – O carriers, an activated sludge oxidation tank with 7.500 m3 volume and sludge concentration 4-6 kgSSTm-3, and a secondary settler. The plant must remove at least 90% of COD, 99% of BOD5; maximum pollutant concentrations in final effluent are: TSS < 50 mg/L, tot-N < 4.7 mg/L, P < 0.3 mg/L.