Impact of Physical and Chemical Cleaning Agents on Specific Biofilm Components and the Implications for Membrane Biofouling Management

Abstract Biofouling is unwanted accumulation of microbial population on the membrane surface which limits the use of membrane bioreactor (MBR) in the market. Disruption of the biofilm formation by Quorum Quenching (QQ) by using cell entrapping beads (CEBs) is an approach with great potential to control membrane biofouling as the beads used provide not only mitigating effect on biofilm formation, by interfering Quorum Sensing, but also physical forces to detach the biofilm from the membrane surface. This research aimed to develop QQ-CEB with locally available chemicals in Pakistan and its application to evaluate the QQ effect together with physical and chemical cleaning. Various CEBs were made of different mixtures of sodium alginate and polyvinyl alcohol (PVA) and their quality was tested considering physical and biological aspects. Rhodococcus sp. BH4 and Pseudomonas putida were entrapped in the CEBs and then introduced in MBR as one of biofouling control methods along with standard backwash and chemical backwash. The CEBs made of specific concentration of PVA were proven to be more durable and helpful in mitigating biofouling as compared to that of sodium alginate. An MBR operated with PVA-alginate QQ CEBs together with chemical backwash showed the best performance without deterioration of effluent quality.

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Preferential loss of high trace element bearing inner calcite in foraminifera during physical and chemical cleaning

Geochemistry Geophysics Geosystems ◽

10.1029/2020gc009419 ◽

2020 ◽

Author(s):

Theresa Fritz‐Endres ◽

Jennifer Fehrenbacher

Keyword(s):

Trace Element ◽

Chemical Cleaning ◽

Preferential Loss ◽

Element Bearing ◽

Physical And Chemical

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Chemical Cleaning of Ultrafiltration Membrane Fouled by Humic Substances: Comparison between Hydrogen Peroxide and Sodium Hypochlorite

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16142568 ◽

2019 ◽

Vol 16 (14) ◽

pp. 2568 ◽

Cited By ~ 5

Author(s):

Kai Li ◽

Shu Li ◽

Tinglin Huang ◽

Chongzhe Dong ◽

Jiawei Li ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Humic Substances ◽

Sodium Hypochlorite ◽

Alkaline Condition ◽

Chemical Cleaning ◽

H2o2 Treatment ◽

Cleaning Agent ◽

Cleaning Agents ◽

Cleaning Efficacy ◽

By Products

Chemical cleaning is indispensable for the sustainable operation of ultrafiltration (UF) system in water and wastewater treatment. Sodium hypochlorite (NaClO) is an established cleaning agent for membranes subject to organic and microbial fouling, but concerns have been raised about the generation of toxic halogenated by-products during NaClO cleaning. Hydrogen peroxide (H2O2) is a potential “green” cleaning agent that can avoid the formation of halogenated by-products. In this work, cleaning efficacy of H2O2 and NaClO for UF membrane fouled by humic substances (HS) was evaluated under a wide pH range, and change of HS’s properties due to reaction with cleaning agents was examined. The cleaning efficacy of H2O2 was lower than that of NaClO at pH 3–9, but it increased to a level (91.4%) comparable with that of NaClO at pH 11. The extents of changes in properties and fouling potential of HS due to reacting with cleaning agents were consistent with their cleaning efficacy. H2O2 treatment at pH 11 significantly increased negative charge of HS molecules, decomposed high-MW molecules, and reduced its fouling potential. Therefore, considering treatment/disposal of cleaning waste and cleaning efficacy, H2O2 cleaning under strong alkaline condition can be a good choice for HS-fouled membrane.

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Study on Chemical Cleaning Agent in Treatment of Abandoned Oil Pipeline

E3S Web of Conferences ◽

10.1051/e3sconf/201911801031 ◽

2019 ◽

Vol 118 ◽

pp. 01031

Author(s):

Fajie Yang ◽

Chunman Li ◽

Jing Li ◽

Hongtao Wang ◽

Siyu Wu ◽

...

Keyword(s):

Developed Countries ◽

Environment Protection ◽

Chemical Cleaning ◽

The Public ◽

Oil Pipeline ◽

Cleaning Agent ◽

Cleaning Agents ◽

Standards And Guidelines ◽

Safety And Environment ◽

Very High

After pipeline construction burst china energy pipeline industry commonly faced with aging and abandonment problem. The study on pipeline abandonment was still in preliminary state, because there is nearly no pipeline abandonment standards and guidelines. Pipeline cleaning is the first step to dispose the abandoned pipeline to eliminate the risk of environment and safety. In foreign developed countries there are many chemical cleaning agents. But this chemical cleaning agent is not suitable for residual of chines pipeline because of oil difference between china and foreign country. The most of residual in china have a very high paraffin and resin-asphaltenes content. So preparation of chemical cleaning suitable for china residual is a challenge on the technology of abandonment pipeline. In this paper two kinds of chemical cleaning agent were prepared to clean the different type of residual. They are hydrophilic chemical cleaning agent and oil soluble chemical cleaning agent. The result of cleaning project shows that the both kind of chemical cleaning have good performance for the abandoned pipeline. The chemical cleaning agents will assist pipeline company to totally clean the abandoned pipeline to ensure the public safety and environment protection.

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Antibiofilm activity of biomolecules: gene expression study of bacterial isolates from brackish and fresh water biofouled membranes

Biologia ◽

10.1515/biolog-2016-0045 ◽

2016 ◽

Vol 71 (3) ◽

Cited By ~ 5

Author(s):

Smita Pal ◽

Asifa Qureshi ◽

Hemant J. Purohit

Keyword(s):

Salicylic Acid ◽

Fresh Water ◽

Industrial Process ◽

Life Time ◽

Antibiofilm Activity ◽

Expression Study ◽

Chemical Cleaning ◽

Natural Agents ◽

Membrane Biofouling ◽

Exopolysaccharides Production

AbstractMembrane biofouling is a common and emerging problem, where cells get cemented and create problems in industrial process. Frequent chemical cleaning used for the treatment of biofouled membrane shortens the membrane life time and creates ‘stress’ to existing microflora to trigger more exopolysaccharides production, which becomes the principle cause of biofouling. To understand safe and environmentally feasible antifouling strategies, key biofilm forming representative bacteria isolated from brackish and fresh water biofouled membranes were subjected to natural agents, such as vanillin (0.05–0.4 mg/mL) and salicylic acid (0.1–0.7 mg/mL). Salicylic acid (0.7 mg/mL) was found to be effective against only

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Stimulatory effects on bacteria induced by chemical cleaning cause severe biofouling of membranes

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2020.062 ◽

2020 ◽

Vol 10 (1) ◽

pp. 82-94

Author(s):

Xueye Wang ◽

Jinxing Ma ◽

Zhichao Wu ◽

Zhiwei Wang

Keyword(s):

Membrane Surface ◽

Oxygen Species ◽

Cleaning Efficiency ◽

Chemical Cleaning ◽

Physiological Mechanisms ◽

Homoserine Lactones ◽

Membrane Surfaces ◽

Enhanced Production ◽

Membrane Biofouling ◽

Microbial Regrowth

Abstract Chemical cleaning with hypochlorite is routinely used in membrane-based processes. However, a high-transient cleaning efficiency does not guarantee a low biofouling rate when filtration is restarted, with the physiological mechanisms largely remaining unknown. Herein, we investigated the microbial regrowth and surface colonization on membrane surfaces after NaOCl cleaning had been completed. Results of this study showed that the regrowth of model bacteria, Pseudomonas aeruginosa, was initially subject to inhibition due to the damage of key enzymes' activity and the accumulation of intracellular reactive oxygen species although the oxidative stress induced by NaOCl had been removed. However, with the resuscitation ongoing, the stimulatory effects became obvious, which was associated with the enhanced production of N-acyl homoserine lactones and the secretion of eDNA that ultimately led to more severe biofouling on the membrane surface. This study elucidates the inhibition–stimulation mechanisms involved in biofilm reformation (membrane biofouling) after membrane chemical cleaning, which is of particular significance to the improvement of cleaning efficiency and application of membrane technologies.

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Strategies for chemical cleaning in large scale membrane bioreactors

Water Science & Technology ◽

10.2166/wst.2008.112 ◽

2008 ◽

Vol 57 (3) ◽

pp. 457-463 ◽

Cited By ~ 38

Author(s):

C. Brepols ◽

K. Drensla ◽

A. Janot ◽

M. Trimborn ◽

N. Engelhardt

Keyword(s):

Large Scale ◽

Membrane Bioreactor ◽

Effective Means ◽

Membrane Bioreactors ◽

Ex Situ ◽

Chemical Cleaning ◽

Membrane Cleaning ◽

Cleaning Agents ◽

Cleaning Procedures ◽

Alkaline Cleaning

Systematically testing alternative cleaning agents and cleaning procedures on a large scale municipal membrane bioreactor, the Erftverband optimized the cleaning strategies and refined the original cleaning procedures for the hollow fiber membranes in use. A time-consuming, intensive ex-situ membrane cleaning twice a year was initially the regular routine. By introducing the effective means of cleaning in place in use today, which employs several acidic and oxidative/alkaline cleaning steps, intensive membrane cleaning could be delayed for years. An overview and an assessment of various cleaning strategies for large scale plants are given.

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UV and bacteriophages as a chemical-free approach for cleaning membranes from anaerobic bioreactors

10.1101/2020.08.03.234450 ◽

2020 ◽

Author(s):

Giantommaso Scarascia ◽

Luca Fortunato ◽

Yevhen Myshkevych ◽

Hong Cheng ◽

TorOve Leiknes ◽

...

Keyword(s):

Wastewater Treatment ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Bioreactor ◽

Combined Treatment ◽

Chemical Cleaning ◽

High Quality ◽

Anaerobic Membrane Bioreactor ◽

Membrane Biofouling ◽

Uv C

ABSTRACTAnaerobic membrane bioreactor (AnMBR) for wastewater treatment has attracted much interest due to its efficacy in providing high quality effluent with minimal energy costs. However, membrane biofouling represents the main bottleneck for AnMBR because it diminishes flux and necessitates frequent replacement of membranes. In this study, we assessed the feasibility of combining bacteriophages and UV-C irradiation to provide a chemical-free approach to remove biofoulants on the membrane. The combination of bacteriophage and UV-C resulted in better log cells removal and twice higher extracellular polymeric substance (EPS) concentration reduction in mature biofoulants compared to UV-C. A reduction in the relative abundance of Acinetobacter spp. and selected gram-positive bacteria associated with the membrane biofilm was also achieved by the new cleaning approach. Microscopic analysis further revealed the formation of cavities in the biofilm due to bacteriophages and UV-C irradiation, which would be beneficial to maintain water flux through the membrane. When the combined treatment was further compared with the common chemical cleaning procedure, a similar reduction on the cell numbers was observed (1.4 log). However, combined treatment was less effective in removing EPS compared with chemical cleaning. These results suggest that the combination of UV-C and bacteriophage have an additive effect in biofouling reduction, representing a potential chemical-free method to remove reversible biofoulants on membrane fitted in an anaerobic membrane bioreactor.SIGNIFICANCEAnaerobic membrane bioreactors can achieve high quality effluent with a reduced energy consumption. However, biofouling represents the main bottleneck for membrane filtration efficiency. Biofouling is commonly reduced through chemical treatment. These agents are often detrimental for the environment and health safety due to the formation of toxic byproducts. Therefore, we present a new approach, based on the additive antifouling action of bacteriophages infection and UV-C irradiation, to reduce anaerobic membrane biofouling. This new strategy could potentially delay the occurrence of membrane fouling by removing the reversible fouling layers on membranes, in turn reducing the frequencies and amount of chemicals needed throughout the course of wastewater treatment.

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