Electrically enhanced MBR system for total nutrient removal in remote northern applications

2012 ◽  
Vol 65 (4) ◽  
pp. 737-742 ◽  
Author(s):  
V. Wei ◽  
M. Elektorowicz ◽  
J. A. Oleszkiewicz
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Climatic Conditions ◽  
Transmembrane Pressure ◽  
Treatment Technology ◽  
Electrically Enhanced ◽  
P Removal

Thousands of sparsely populated communities scatter in the remote areas of northern Canada. It is economically preferable to adopt the decentralized systems to treat the domestic wastewater because of the vast human inhabitant distribution and cold climatic conditions. Electro-technologies such as electrofiltration, elctrofloatation, electrocoagulation and electrokinetic separation have been applied in water and conventional wastewater treatment for decades due to the minimum requirements of chemicals as well as ease of operation. The membrane bioreactor (MBR) is gaining popularity in recent years as an alternative water/wastewater treatment technology. However, few studies have been conducted to hyphenate these two technologies. The purpose of this work is to design a novel electrically enhanced membrane bioreactor (EMBR) as an alternative decentralized wastewater treatment system with improved nutrient removal and reduced membrane fouling. Two identical submerged membranes (GE ZW-1 hollow fiber module) were used for the experiment, with one as a control. The EMBR and control MBR were operated for 4 months at room temperature (20 ± 2 °C) with synthetic feed and 2 months at 10 °C with real sewage. The following results were observed: (1) the transmembrane pressure (TMP) increased significantly more slowly in the EMBR and the interval between the cleaning cycles of the EMBR increased at least twice; (2) the dissolved chemical oxygen demand (COD) or total organic carbon (TOC) in the EMBR biomass was reduced from 30 to 51%, correspondingly, concentrations of the extracellular polymeric substances (EPS), the major suspicious membrane foulants, decreased by 26–46% in the EMBR; (3) both control and EMBR removed >99% of ammonium-N and >95% of dissolved COD, in addition, ortho-P removal in the EMBR was >90%, compared with 47–61% of ortho-P removal in the MBR; and (4) the advantage of the EMBR over the conventional MBR in terms of membrane fouling retardation and phosphorus removal was further demonstrated at an operating temperature of 10 °C when fed with real sewage. The EMBR system has the potential for highly automated control and minimal maintenance, which is particularly suitable for remote northern applications.

Pilot Scale Study on Biological Nutrient Removal and Membrane Fouling Alleviation in Combined Membrane Bioreactor for Municipal Wastewater Treatment

2011 ◽  
Vol 365 ◽  
pp. 354-360 ◽  
Author(s):  
Shuo Liu ◽  
Ji Fu Wang ◽  
Bao Zhen Wang ◽  
Bing Wang ◽  
Wei Wan
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Municipal Wastewater ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Biological Nutrient Removal ◽  
Municipal Wastewater Treatment ◽  
Nutrient Removal Rate

To solve the problem of eutrophication in receiving water, a novel Membrane Bioreactor (MBR) with combined configuration was designed for municipal wastewater treatment and reclamation. By dividing bioreactor into three zones, the combined MBR operated under anoxic, anaerobic and aerobic conditions. It provided optimum conditions for nitrification, denitrifying and phosphate accumulating bacterial growth which resulted in high biological nutrient removal rate directly. The operational performance of combined MBR pilot plant showed that it exhibited high nutrient removal rate on Chemical oxygen demand (CODcr), total nitrogen (TN) and total phosphorus (TP). The mean value of effluent CODcr, TN and TP removal rate was 90.63%, 63.05% and 60.51% respectively during 180 days of operation. In order to obtain stable membrane flux, the combined MBR packed with fibrous bio-film carrier and added diatomite. Furthermore, it could alleviate membrane fouling effectively. As a result, the combined MBR improved effluent water quality significantly and alleviated membrane fouling remarkably.

scholarly journals Mechanism of Membrane Fouling Control by HMBR: Effect of Microbial Community on EPS

2020 ◽  
Vol 17 (5) ◽  
pp. 1681
Author(s):  
Qiang Liu ◽  
Ying Yao ◽  
Delan Xu
Keyword(s):  
Microbial Community ◽  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Microbial Community Composition ◽  
Domestic Wastewater ◽  
Control Group ◽  
Transmembrane Pressure ◽  
Fouling Control ◽  
Cake Layer

A hybrid membrane bioreactor (HMBR) employing activated sludge and biofilm simultaneously is proved to represent a good performance on membrane fouling control compared to conventional membrane bioreactor (CMBR) by reducing extracellular polymeric substances (EPS), especially bound EPS (B-EPS). In order to better understand the mechanism of membrane fouling control by the HMBR in regard of microbial community composition, a pilot scale HMBR operated to treat domestic wastewater for six months, and a CMBR operated at the same time as control group. Results showed that HMBR can effectively control membrane fouling. When transmembrane pressure reached 0.1 MPa, the membrane module in the HMBR operated for about 26.7% longer than that in the CMBR. In the HMBR, the quantity of EPS was significantly lower than that in the CMBR. In this paper, soluble EPS was also found to have a close relationship with cake layer resistance. The species richness and diversity in the HMBR were higher than those in the CMBR, and a certain difference between the compositions of microbial communities in the two reactors was confirmed. Therefore, the difference in microbial community compositions may be the direct reason why EPS in the HMBR was lower than that in the CMBR.

scholarly journals Nutrients Enrichment and Process Repercussions in Hybrid Microfiltration Osmotic Membrane Bioreactor: A Guideline for Forward Osmosis Development Based on Lab-Scale Experience

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1098
Author(s):  
Khum Gurung ◽  
Morten Lykkegaard Christensen ◽  
Mika Sillanpää ◽  
Mohamed Chaker Ncibi ◽  
Mads Koustrup Jørgensen
Keyword(s):  
Water Permeability ◽  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Forward Osmosis ◽  
Microbial Inactivation ◽  
Transmembrane Pressure ◽  
Pressure Step ◽  
Draw Solution ◽  
Osmotic Membrane Bioreactor

The effects of reverse salt diffusion through a forward osmosis membrane were studied in a microfiltration osmotic membrane bioreactor. The reactor was used to treat and simultaneously concentrate nutrients from wastewater. The system was operated at different draw solution concentrations, leading to varying salinity conditions. A relatively low, yet stable forward osmosis flux was observed regardless of increasing draw solution conductivities from 10 to 50 mS cm−1. A substantial increase in sludge conductivity from 5.7 to 19.8 mS cm−1 was observed during the operation. Batch transmembrane pressure-step experiments showed a decline in sludge filtration properties with increasing salinity buildup in sludge due to increasing deflocculation and associated release of protein and carbohydrate fractions of extracellular polymeric substances. Mathematical simulations showed that accumulation of total dissolved solids could mainly be attributed to reverse flux of salts from the draw solution rather than by the enrichment of incoming nutrients when forward osmosis membrane’s salt permeability was high and water permeability low. Ideally, salt permeability below 0.010 L m−2 h−1 and effective water permeability above 0.13 L m−2 h−1 bar−1 are crucial to ensure enhanced nutrient enrichment and reduce sludge osmotic pressure, microbial inactivation, sludge deflocculation and membrane fouling.

scholarly journals Characterization of the Fouling Layer on the Membrane Surface in a Membrane Bioreactor: Evolution of the Foulants’ Composition and Aggregation Ability

Membranes ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 85 ◽  
Author(s):  
Linlin Yan ◽  
Ruixue Li ◽  
Yu Song ◽  
Yanping Jia ◽  
Zheng Li ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Membrane Surface ◽  
Extracellular Dna ◽  
Transmembrane Pressure ◽  
Average Roughness ◽  
Three Stages ◽  
Fast Rise

In this study, the characteristics of membrane foulants were analyzed with regard to morphology, composition, and aggregation ability during the three stages of transmembrane pressure (TMP) development (fast–slow–fast rise in TMP) in a steady operational membrane bioreactor (MBR). The results obtained show that the fouling layer at the slow TMP-increase stage possessed a higher average roughness (71.27 nm) and increased fractal dimension (2.33), which resulted in a low membrane fouling rate (0.87 kPa/d). A higher extracellular DNA (eDNA) proportion (26.12%) in the extracellular polymeric substances (EPS) resulted in both higher zeta potential (-23.3 mV) and higher hydrophobicity (82.3%) for initial foulants, which induced and increased the protein proportion in the subsequent fouling layer (74.11%). Furthermore, the main composition of the EPS shifted from protein toward polysaccharide dominance in the final fouling layer. The aggregation test confirmed that eDNA was essential for foulant aggregation in the initial fouling layer, whereas ion interaction significantly affected foulant aggregation in the final fouling layer.

scholarly journals Membrane fouling reduction in a cost-effective integrated system of microbial fuel cell and membrane bioreactor

2017 ◽  
Vol 76 (3) ◽  
pp. 653-661 ◽  
Author(s):  
Benai Cheng ◽  
Jie Wang ◽  
Wenbin Liu ◽  
Zhao Cui ◽  
Fanghua Bi ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Membrane Fouling ◽  
Microbial Fuel Cells ◽  
Extracellular Polymeric Substances ◽  
Oxygen Demand ◽  
Operation Time ◽  
Cost Effective ◽  
Integrated System ◽  
Treatment Technology ◽  
Fouling Reduction

Microbial fuel cells (MFC) and membrane bioreactors (MBR) are promising technologies for wastewater treatment. However, both of them have some drawbacks and application limitations. A cost-effective hybrid system (EMBR) integrating MFC with MBR was evaluated in terms of treatment performance and membrane fouling. In this paper, two electric field directions with a membrane module in the middle were applied to explore the mechanism of membrane fouling mitigation in EMBRs. In both configurations of EMBRs, microbial activity and degradation ability of activated sludge for chemical oxygen demand and NH4+−N removals could be enhanced compared with those for the controlled MBR. In addition, the irreversible resistance significantly decreased, especially in the EMBR(−) with a longer operation time. Furthermore, two critical factors, namely enhanced bioflocculation and electrophoresis forces, were compared based on key parameters (zeta potential, particle size distribution and extracellular polymeric substances). The electrophoresis forces made a greater contribution to fouling alleviation than that conducted by the enhanced bioflocculation. The results suggested that EMBR, as a promising wastewater treatment technology, improved effluent quality and reduced energy consumption.

scholarly journals Influence of Material on Membrane Fouling and Cleaning Results of Mustard Tuber Wastewater Treatment by Membrane Bioreactor

2014 ◽  
Vol 26 (11) ◽  
pp. 3246-3248
Author(s):  
Hongxiang Chai ◽  
Luwei Guo ◽  
Yinghua Wei ◽  
Jun Du ◽  
Jian Zhou ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Membrane Fouling ◽  
Membrane Bioreactor

Investigation of long-term operation and biomass activity in a membrane bioreactor system

2011 ◽  
Vol 63 (9) ◽  
pp. 1906-1912 ◽  
Author(s):  
Simos Malamis ◽  
Andreas Andreadakis ◽  
Daniel Mamais ◽  
Constantinos Noutsopoulos
Keyword(s):  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Operating Conditions ◽  
Term Operation ◽  
Solids Retention ◽  
Biomass Activity ◽  
Long Term Performance ◽  
Term Performance

The aim of this work was to evaluate the long-term performance of a Membrane Bioreactor (MBR) that operated continuously for 2.5 years and to assess membrane fouling and biomass activity under various operating conditions. Furthermore, a method for the characterisation of influent wastewater was developed based on its separation into various fractions. The MBR system operated at the solids retention times (SRT) of 10, 15, 20 and 33 days. The increase of SRT resulted in a decrease of the fouling rate associated with the reduction of extracellular polymeric substances. Moreover, the SRT increase resulted in a significant reduction of the Oxygen Uptake Rate (OUR) due to the lower availability of substrate and in a notable decrease of the maximum OUR since high SRT allowed the development of slower growing microorganisms. Biomass consisted of small flocs due to extensive deflocculation caused by intense aeration. Finally, the method developed for wastewater characterisation is straightforward and less time consuming than the usual method that is employed.

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