Recent Papers in Biofilm Processes
Content Table
- Hybrid moving bed biofilm reactors: an effective solution for upgrading a large wastewater treatment plant
- Biofilm/membrane filtration for reclamation and reuse of rural wastewaters
- Influence of carrier type on nitrification in the moving-bed biofilm process
- Municipal wastewater treatment through an aerobic biofilm SBR integrated with a submerged filtration bed
- Detection and monitoring of biofilm formation in water treatment systems by quartz crystal microbalance sensors
- Pumped flow biofilm reactors (PFBR) for treating municipal wastewater
- Analysis of nitrifying bacterial communities in aerobic biofilm reactors with different DO conditions using molecular techniques
- Where are we with biofilms now? Where are we going?
- Wastewater treatment with submerged fixed bed biofilm reactor systems – design rules, operating experiences and ongoing developments
- Effect of temperature and salinity on the wastewater treatment performance of aerobic submerged fixed bed biofilm reactors
Hybrid moving bed biofilm reactors: an effective solution for upgrading a large wastewater treatment plant
Water Science & Technology—WST Vol 60 No 5 pp 1103–1116 © IWA Publishing 2009 doi:10.2166/wst.2009.416
Giorgio Mannina and Gaspare Viviani
Dipartimento di Ingegneria Idraulica ed Applicazioni Ambientali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy E-mail: mannina@idra.unipa.it
Abstract
Over the last few years there has been a growing attention regarding the receiving water body quality state. As a matter of a fact, the Directive 91/271 of the European Union (EU) replaced the “emission standard” concept that fixes discharge limits depending on polluting emission characteristics, with the “stream standard” concept that fixes discharge limits for each polluting substance depending on self-depurative characteristics of the RWB. In this context, several WWTPs need to be upgraded in order to meet stricter effluent limits. The need of WWTP upgrading was also emphasized by the growing urbanization that have led, in most cases, to get overloaded WWTP due to an overcoming of the maximum WWTP capacity. In order to upgrade existing WWTP basically two main possibilities can be chosen: building new tanks or modify the WWTP by introducing new technologies such as the HMBBR systems. In this paper, such latter possibility was explored and as a case study an existing Italian WWTP (Acqua dei Corsari) located in Palermo (IT) was analysed. The main goal was to test the effectiveness of HMBBR systems with respect to the WWTP upgrading. The survey was carried out by means of model simulation and an HMBBR pilot plant. This latter was employed for the evaluation of the model parameters as well as kinetic coefficients for the HMBBR. The model results are encouraging towards the WWTP upgrading by means of HMBBR. As a matter of fact, the model simulation results showed that the WWTP maximum capacity can be upgraded from 480,000 up to one million PE.
Biofilm/membrane filtration for reclamation and reuse of rural wastewaters
Water Science & Technology—WST Vol 59 No 11 pp 2145–2152 © IWA Publishing 2009 doi:10.2166/wst.2009.232
Kil-Soo Hyun and Seok-Ju Lee
Department of Urban Environmental Engineering, Kyungpook National University, 386 Gajang-dong, Sangju, Kyungsangbuk-do 742-711, South Korea E-mail: kshyun@knu.ac.kr
Abstract
To cost-effectively meet water quality and quantity requirements for rural areas, the objective of this research was to evaluate the performances of a three-stage process of anaerobic-oxic-anoxic biofilm filtration (AOBF) and membrane filtration (MF) processes and to assess the potential for reclamation and reuse of blended wastewater contained domestic wastewater, black water, and landfill leachate. The AOBF process at < LV 30 m/day showed good removal results of >90% for conventional pollutants (>75% for COD) and >70% for nutrient. Influent step-feeding with 0.8Q into filter bed 1 and 0.2Q into filter bed 2 achieved denitrification efficiency of 5–10% higher than without step feed. Efficiencies of plate membrane removal were greater than 90% for COD and more than approximate 75% for nutrients and heavy metals, respectively. The AOBF/MF system showed excellent removal results of >90–95% for soluble nutrients as well as nonsoluble fractions such as TSS, particulate COD. The effluent of AOBF/MF system met the reuse standard for industrial and agricultural water, while effluent of AOBF met the standard for the effluent quality of wastewater treatment plants. These results indicate that the AOBF/MF system was suitable for rural integrated wastewater treatment by achieving cost-effectively an effluent quality able to be used for industrial, agricultural and water bodies recharge purposes.
Influence of carrier type on nitrification in the moving-bed biofilm process
Water Science & Technology—WST Vol 59 No 5 pp 875–882 © IWA Publishing 2009 doi:10.2166/wst.2009.037
M. Levstek and I. Plazl
JP CCN Domzale-Kamnik d.o.o. (Domzale-Kamnik WWTP), Studljanska 91, Domzale, 1230, Slovenia E-mail: levstek@ccn-domzale.si
Department of Chemical Engineering, University of Ljubljana, Askerceva 5, Ljubljana, 1001, Slovenia E-mail: igor.plazl@fkkt.uni-lj.si
Abstract
Two different types of carriers differing fundamentally in size, shape and structure were evaluated in parallel testing for nitrification potential using the moving-bed biofilm reactor (MBBR) technology. One of the carriers used was a cylindrical high-density polyethylene ring shaped carrier (AnoxKaldnes, K1 carrier) and the other was a spherical polyvinyl alcohol (PVA) gel bead shaped carrier (Kuraray, PVA-gel carrier). For each MBBR process, using artificial wastewater under autotrophic conditions, high maximal nitrification rates at 20°C were obtained. For the K1 carrier up to 27 mgNH4-N/L.h (at 37% filling fraction) was found, corresponding to 49 mgNH4-N/L.h at the recommended maximum filling fraction of 67%. This corresponds to a nitrification area rate of 3.5 gNH4-N/m2.d for the K1 carrier at 20°C. For the PVA-gel carrier up to 32 mgNH4-N/L.h (at 9.6% filling fraction) was found, corresponding to 50.0 mg NH4-N/L.h at the recommended maximum filling fraction of 15%. At the recommended filling fractions, the two carriers therefore required about the same reactor volume to reach the maximum observed nitrification rate. This presumption allowed us to estimate the effective specific surface area for the PVA gel carrier up to 2,500 m2/m3 versus 1,000 m2/m3 when only the outer surface is considered.
Municipal wastewater treatment through an aerobic biofilm SBR integrated with a submerged filtration bed
Water Science & Technology—WST Vol 59 No 5 pp 917–926 © IWA Publishing 2009 doi:10.2166/wst.2009.041
Kai Yang, Jiajie He, Mark Dougherty, Xiaojun Yang and Lu Li
School of Civil Engineering, Wuhan University, Wuhan, 430072, China E-mail: yangkaiz@126.com; lilu19841110@163.com
Civil Engineering Department, Auburn University, Auburn, Alabama 36849, USA E-mail: shejiaji@auburn.edu
Biosystems Engineering Department, Auburn University, Auburn, Alabama 36849, USA E-mail: doughmp@auburn.edu
Abstract
A biofilm reactor and a gravitational filtration bed were integrated as a sequencing batch reactor (SBR) to aerobically treat a municipal wastewater. Polyacrylonitrile balls (50 mm diameter, 90% porosity) were filled into the upper part of the SBR as biofilm attaching materials and anthracite coal (particle size ~1.17 mm) was placed into the lower part as filter media. The SBR was aerated during filling and reaction phases, followed by a 10 min discharge phase during which the wastewater went through the filtration bed without aeration. The SBR was tested with raw wastewater from a municipal WWTP in Wuhan, China from July 2006 to January 2007, during both a warm season and a cold season. The SBR showed a capability to accept COD and turbidity fluctuations in the receiving wastewater. Seasonal influence on COD and nitrogen removal by the biofilm reactor was significant. Nitrogen and phosphorus removals were limited by COD levels in the wastewater. The filtration process removed considerable COD, nitrogen, phosphorus, and turbidity. The overall SBR effluent quality consistently satisfied the national secondary effluent discharge standard of China, except for total phosphorus. An anaerobic phase before the aerobic reaction is proposed to improve phosphorus and nitrogen removal. The filter normally required a backwash every seven days and the water needed for backwash was less than 4% of the wastewater treated by the SBR. This experiment provides information needed for further investigation to improve performance of the SBR.
Detection and monitoring of biofilm formation in water treatment systems by quartz crystal microbalance sensors
Water Science & Technology—WST Vol 59 No 3 pp 543–548 © IWA Publishing 2009 doi:10.2166/wst.2009.001
C. Sprung, D. Wählisch, R. Hüttl, J. Seidel, A. Meyer and G. Wolf
Institut f. Physikalische Chemie, TU Bergakademie Freiberg, Freiberg, D-09596, Germany E-mail: regina.huettl@chemie.tu-freiberg.de
UMEX GmbH Dresden, Dresden, D-01109, Germany E-mail: ame@umex.de
Abstract
Investigations are presented for the development and testing of a sensor for the early stage detection and monitoring of biofilm formation. The sensor is based on the well known quartz crystal microbalance technology (QCM). The QCM detectors are integrated into the water flow system and provide continuous in-situ signals. The main objectives of the research are the evaluation of optimal operation conditions and the modification of the quartz resonator surface promoting a preferred cell attachment onto the quartz sensor surface. The miniaturization degree of the mass sensitive detector modules permits the integration into industrial plants, e.g., in order to control and ensure perfect hygienic conditions. First results of the lab study using Pseudomonas putida cultures are presented and discussed.
Pumped flow biofilm reactors (PFBR) for treating municipal wastewater
Water Science & Technology—WST Vol 57 No 12 pp 1857–1865 © IWA Publishing 2008 doi:10.2166/wst.2008.327
E. O'Reilly, M. Rodgers and X.-M. Zhan
Department of Civil Engineering, National University of Ireland, Galway, Ireland E-mail: edmond.oreilly@nuigalway.ie; michael.rodgers@nuigalway.ie; xinmin.zhan@nuigalway.ie
Abstract
A novel laboratory bench-scale sequencing batch biofilm reactor (SBBR) system was developed for the treatment of synthetic domestic strength wastewater, comprising two side-by-side 18 l reactor tanks, each containing a plastic biofilm media module. Aerobic and anoxic conditions in the biofilms were effected by intermittent alternate pumping of wastewater between the two reactors. With a media surface area loading rate of 4.2 g chemical oxygen demand (COD)/m2.d, the average influent COD, total nitrogen (TN) and ammonium-nitrogen (NH4-N) concentrations of 1021 mg/l, 97 mg/l and 54 mg/l, respectively, reduced to average effluent concentrations of 72 mg COD/l, 17.8 mg TN/l, and 5.5 mg NH4-N /l. Using a similar alternating biofilm exposure arrangement, a 16 person equivalent pilot (PE) plant was constructed at a local village treatment works to remove organic carbon from highly variable settled municipal wastewater and comprised two reactors, one positioned above the other, each containing a module of cross-flow plastic media with a surface area of 100 m2. Two different pumping sequences (PS) in the aerobic phase were examined where the average influent COD concentrations were 220 and 237 mg/l for PS1 and PS2, respectively, and the final average effluent COD was consistently less than 125 mg/l – the European Urban Wastewater Treatment Directive limit – with the best performance occurring in PS1. Nitrification was evident during both PS1 and PS2 studies. A 300 PE package treatment plant was designed based on the bench-scale and pilot-scale studies, located at a local wastewater treatment works and treated municipal influent with average COD, suspended solids (SS) and TN concentrations of 295, 183 and 15 mg/l, respectively resulting in average effluent concentrations of 67 mg COD/l, 17 mg SS/l and 9 mg TN/l. The SBBR systems performed well, and were simple to construct and operate.
Analysis of nitrifying bacterial communities in aerobic biofilm reactors with different DO conditions using molecular techniques
Water Science & Technology—WST Vol 57 No 12 pp 1889–1899 © IWA Publishing 2008 doi:10.2166/wst.2008.622
J. J. Park, I. G. Byun, J. C. Yu, S. R. Park, D. J. Ju, S. H. Hur and T. J. Park
School of Civil and Environmental Engineering, Pusan National University, 609-735, Busan, Korea E-mail: taejoo@pusan.ac.kr
Abstract
In order to assess the relationship between the dissolved oxygen (DO) concentration and the characteristics of nitrifying bacterial communities in an aerobic biofilm reactor, molecular techniques including denaturing gradient gel electrophoresis (DGGE)/cloning based on PCR targeting 16S rRNA and the amoA gene and fluorescence in situ hybridisation (FISH) were conducted. The D-1, D-2, D-3 and D-4 reactors with different DO concentrations (1, 3, 5 and 7 mg/L, respectively) were set up in the thermostat and acclimated. The optimal DO concentration with stable nitrification efficiency was above 5.0 mg/L. As was shown by the results of DGGE and cloning, the community of ammonia-oxidising bacteria (AOB) and the ratio of Nitrosomonas sp. changed only slightly despite their differing nitrification efficiencies. The results of FISH indicated that higher DO concentrations resulted in an increase in AOB and nitrite-oxidising bacteria (NOB), and a reduction in heterotrophic microorganisms. The INT-dehydrogenase activity (DHA) test demonstrated that the activity of AOB decreased with reductions in the DO concentration. This means that the DO concentration does not influence the community of AOB, but rather the activity of AOB. In the relationship between the attached biomass and the nitrification efficiency, only the active biomass affected the nitrification efficiencies.
Where are we with biofilms now? Where are we going?
Water Science & Technology Vol 55 No 8-9 pp 1–7 © IWA Publishing 2007 doi:10.2166/wst.2007.235
B.E. Rittmann
Arizona State University, Center for Environmental Biotechnology, 1001 SPO. Box 875701, Tempe, AZ 85287-5701, USA (E-mail: rittmann@asu.edu)
Abstract
The IWA's BiofilmVI conference presented a wide range of research on biofilm systems. Particularly popular themes were nitrogen removal, mathematical modelling and microbial ecology. Emerging themes included biofilms with membranes, pathogens in biofilms, biofouling and detachment. Within microbial ecology and mathematical modelling, emphasis was given to N-removal systems, particularly involving nitrifiers and Anammox bacteria. Both themes also recognised the importance of biofilm detachment. Although biofilms on membranes gained attention, little interest was exhibited towards linking biofilms with other advanced materials, such as ceramics, conductors, semi-conductors or nano-materials. Research presented at BiofilmVI marked major advances in improving water sustainability towards removing BOD and N, but did not address many emerging contaminants, such as oxidised contaminants and endocrine disruptors. Attention to energy sustainability, such as with bio-hydrogen or microbial fuel cells, was minimal. Thus, research reported at BiofilmVI was strong towards “improving the expected” with regard to BOD and N removal, but not yet focused on “exploiting the unexpected” to deal with emerging pollutants and bio-energy.
Wastewater treatment with submerged fixed bed biofilm reactor systems – design rules, operating experiences and ongoing developments
Water Science & Technology Vol 55 No 8-9 pp 83–89 © IWA Publishing 2007 doi:10.2166/wst.2007.245
S. Schlegel and H. Koeser
Martin-Luther-University Halle-Wittenberg, Department of Engineering Science, Institute of Environmental Engineering D-06099 , Halle, Germany (E-mail: ust-mail@iw.uni-halle.de)
Abstract
Wastewater treatment systems using bio-films that grow attached to a support media are an alternative to the widely used suspended growth activated sludge process. Different fixed growth biofilm reactors are commercially used for the treatment of municipal as well as industrial wastewater.
In this paper a fairly new fixed growth biofilm system, the submerged fixed bed biofilm reactor (SFBBR), is discussed. SFBBRs are based on aerated submerged fixed open structured plastic media for the support of the biofilm. They are generally operated without sludge recirculation in order to avoid clogging of the support media and problems with the control of the biofilm. Reactor and process design considerations for these reactors are reviewed. Measures to ensure the development and maintenance of an active biofilm are examined. SFBBRs have been applied successfully to small wastewater treatment plants where complete nitrification but no high degree of denitrification is necessary. For the pre-treatment of industrial wastewater the use of SFBBRs is advantageous, especially in cases of wastewater with high organic loading or high content of compounds with low biodegradability. Performance data from exemplary commercial plants are given. Ongoing research and development efforts aim at achieving a high simultaneous total nitrogen (TN) removal of aerated SFBBRs and at improving the efficiency of TN removal in anoxic SFBBRs
Effect of temperature and salinity on the wastewater treatment performance of aerobic submerged fixed bed biofilm reactors
Water Science & Technology Vol 55 No 8-9 pp 159–164 © IWA Publishing 2007 doi:10.2166/wst.2007.254
G. Chapanova, M. Jank, S. Schlegel and H. Koeser
Martin-Luther-University Halle-Wittenberg, Institute of Environmental Engineering D-06099 , Halle, Germany (E-mail: ust-mail@iw.uni-halle.de)
Abstract
The influence of temperature (5–35 °C) and salinity (up to 20 g/l NaCl) on the wastewater purification process in completely mixed and aerated submerged fixed bed biofilm reactors (SFBBRs) was studied. C- and N-conversion in SFBBRs designed according to the DWA (German Association for Water, Wastewater and Waste) rules for carbon removal was investigated for several months on synthetic wastewater.
The DOC degradation rate was even at, according to the DWA, high DOC/BOD loading rates not much affected by temperatures between 5–35 °C and salt contents up to 20 g/L NaCl. At these high DOC loadings an appreciable ammonium conversion could also be observed. The ammonium conversion proved to be sensitive to temperature and salinity. At 5 °C the ammonium removal rate decreased by a factor of five compared to 25–35 °C. Under many operation conditions investigated more than 50% of the converted ammonium was transformed into gaseous nitrogen. The addition of 20 g/L NaCl caused a strong inhibition of the ammonium removal rate over the whole temperature range investigated.
