New insights into comparison between synthetic and practical municipal wastewater in cake layer characteristic analysis of membrane bioreactor

The paper outlines a model of the filtration performance of submerged capillary microfiltration modules in membrane bioreactor applications for wastewater treatment. The model was implemented for process simulation and calibrated by using operating data of the full-scale municipal wastewater treatment plant Rödingen, Germany, operated by Erft River Association (Erftverband), which is equipped with activated sludge treatment and microfiltration units for biomass retention. Mathematically recordable foundations of filtration resistances, such as cake layer forming and fouling, are presented along with a mass transfer model, describing the concentration polarisation on the feed-side and its dependence on a multiphase flow regime. The model simulates the long-term decrease in permeability of the membranes and outlines the influence of main operating parameters on flux performance. After parameter fitting for one filtration unit, the permeability evolution for a second unit could be also calculated.

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Permeability decline in nanofiltration/reverse osmosis membranes fed with municipal wastewater treated by a membrane bioreactor

Water Science & Technology ◽

10.2166/wst.2013.080 ◽

2013 ◽

Vol 67 (9) ◽

pp. 1994-1999 ◽

Cited By ~ 4

Author(s):

Katsuki Kimura ◽

Naoko Ogawa ◽

Yoshimasa Watanabe

Keyword(s):

Organic Matter ◽

Reverse Osmosis ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Membrane Surface ◽

Chemical Cleaning ◽

Filtration Resistance ◽

Cake Layer ◽

Total Filtration ◽

Ro Membrane

Decline in the permeability in nanofiltration (NF)/reverse osmosis (RO) membranes that filtered effluents from a membrane bioreactor (MBR) treating municipal wastewater was investigated in this study. Four different 2-inch spiral-wound NF/RO membrane elements were continuously operated for 40 days. The results showed that the amount of deposits on the membrane surface did not affect the degree of permeability decline. Laboratory-scale filtration tests with coupons obtained from the fouled membranes also revealed that the contribution of the gel/cake layer to total filtration resistance was minor. Rather, constituents that were strongly bound to the membranes were mainly responsible for permeability decline. Chemical cleaning of the fouled membranes carried out after removal of the cake showed that silica played an important role in the decline in permeability. A considerable amount of organic matter which was mainly composed of carbohydrates and proteins was also desorbed from the fouled membranes.

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Microbial communities in an anaerobic dynamic membrane bioreactor (AnDMBR) for municipal wastewater treatment: Comparison of bulk sludge and cake layer

Process Biochemistry ◽

10.1016/j.procbio.2013.02.003 ◽

2013 ◽

Vol 48 (3) ◽

pp. 510-516 ◽

Cited By ~ 57

Author(s):

Jinxing Ma ◽

Zhiwei Wang ◽

Xinxia Zou ◽

Jiajun Feng ◽

Zhichao Wu

Keyword(s):

Wastewater Treatment ◽

Microbial Communities ◽

Membrane Bioreactor ◽

Municipal Wastewater ◽

Municipal Wastewater Treatment ◽

Dynamic Membrane ◽

Treatment Comparison ◽

Cake Layer ◽

Dynamic Membrane Bioreactor

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Nitrogen Removal in a Real-Time Controlled Sequencing Batch Membrane Bioreactor

Water Practice & Technology ◽

10.2166/wpt.2010.065 ◽

2010 ◽

Vol 5 (3) ◽

Author(s):

Cheng-Nan Chang ◽

Li-Ling Lee ◽

Han-Hsien Huang ◽

Ying-Chih Chiu

Keyword(s):

Real Time ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Synthetic Wastewater ◽

Real Time Control ◽

Time Control ◽

Cake Layer ◽

On Line ◽

Solid Liquid ◽

Solid Liquid Separation

The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-time control of the biological process. Under appropriate ammonia loading rates, applicable ammonia valley and nitrate knee are detected. The real-time control of the SBMBR can be performed based on on-line ORP and pH measurements.

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Gravity-Driven Membrane Reactor for Decentralized Wastewater Treatment: Effect of Reactor Configuration and Cleaning Protocol

Membranes ◽

10.3390/membranes11060388 ◽

2021 ◽

Vol 11 (6) ◽

pp. 388

Author(s):

Ihtisham Ul Haq Shami ◽

Bing Wu

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Economic Feasibility ◽

Reactor Configuration ◽

Membrane Performance ◽

Decentralized Wastewater Treatment ◽

Water Head ◽

Cake Layer ◽

Gravity Driven ◽

Cleaning Protocol

In this study, three gravity-driven membrane (GDM) reactors with flat sheet membrane modules and various biocarriers (synthetic fibers, lava stones, and sands) were operated for municipal wastewater treatment. The effects of water head, periodically cleaning protocol, and operation temperature on the GDM reactor performance were illustrated in terms of membrane performance and water quality. The results indicated that: (1) the cake layer fouling was predominant (>~85%), regardless of reactor configuration and operation conditions; (2) under lower water head, variable water head benefited in achieving higher permeate fluxes due to effective relaxation of the compacted cake layers; (3) the short-term chemical cleaning (30–60 min per 3–4 days) improved membrane performance, especially when additional physical shear force was implemented; (4) the lower temperature had negligible effect on the GDM reactors packed with Icelandic lava stones and sands. Furthermore, the wastewater treatment costs of the three GDM reactors were estimated, ranging between 0.31 and 0.37 EUR/m3, which was greatly lower than that of conventional membrane bioreactors under lower population scenarios. This sheds light on the technical and economic feasibility of biocarrier-facilitated GDM systems for decentralized wastewater treatment in Iceland.

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