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Biofilms Controlling in Industrial Cooling Water Systems: A Mini-Review of Strategies and Best Practices
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DOI: 10.1021/acsabm.3c00319
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Biofilms Controlling in Industrial Cooling Water Systems: A Mini- Review of Strategies and Best Practices
Hening Wang, Yuanzhe Li, * Haoyi Yang, Ken-An Lin, Tiancheng Shao, and James Hope
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Metrics & More Article RecommendationsABSTRACT: Biofilm formation and growth is a significant concern for water treatment professionals, as it can lead to the contamination of water systems and pose a threat to public health. Biofilms are complex communities of microorganisms that adhere to surfaces and are embedded in an extracellular matrix of polysaccharides and proteins. They are notoriously difficult to control, as they provide a protective environment for bacteria, viruses, and other harmful organisms to grow and proliferate. This review article highlights some of the factors that favor biofilm growth, as well as various strategies for controlling biofilm in water systems. Adopting the best available technologies, such as wellhead protection programs, proper industrial cooling water system maintenance, and filtration and disinfection, can prevent the formation and growth of biofilms in water systems. A comprehensive and multifaceted approach to biofilm control can reduce the occurrence of biofilms and ensure the delivery of high-quality water to the industrial process.
KEYWORDS: bacteria interactions, biofilm attachment, industrial cooling water system, control strategy, biofilm removal
1. INTRODUCTION
Industrial cooling water systems are commonly used in various manufacturing processes to maintain equipment and materials at an optimal temperature. However, these systems are susceptible to bacterial growth, which can lead to the formation of biofilms on the surfaces of pipes, tower packing surfaces, and areas with low water flow. Biofilms can create numerous challenges in terms of monitoring and maintaining the water quality, posing a risk to the health of workers and consumers. Therefore, the control and management of biofilms in industrial cooling water systems are of paramount importance. In this mini-review, we will discuss the nature of biofilms and their composition, the challenges they present in terms of control and removal, and the strategies and best practices used to prevent and control biofilm growth in industrial cooling water system (Figure 1).
Biofilms are complex communities of microorganisms that adhere to surfaces and form a slimy matrix of extracellular polymeric substances (EPS).1The EPS matrix is composed of various organic and inorganic substances, including poly- saccharides, proteins, lipids, and minerals.2 This matrix acts as a protective barrier against biocides, antimicrobial agents, and other disinfectants, making it difficult to remove or control biofilms. Bacterial growth in biofilms is typically slower than planktonic bacteria, and the microorganisms in biofilms are more resistant to environmental stresses, including disinfec- tants, than their free-living counterparts.3The EPS matrix also
provides a nutrient-rich environment for the microorganisms, allowing them to survive and thrive in industrial cooling water systems. To address the issue of bacterial growth in cooling water, various strategies are employed by industrial companies.
In cooling systems, various types of biofilms can form, but some of the most common include bacterial biofilms. These biofilms are typically composed of a complex community of bacteria embedded within an extracellular matrix. Some of the common bacteria found in cooling system biofilms include Pseudomonas aeruginosa, Legionella pneumophila, and sulfate- reducing bacteria.4 Controlling biofilms in industrial cooling water systems can be challenging due to the presence of numerous factors that contribute to their growth and persistence. Factors such as temperature, pH, nutrients, and dissolved solids can affect the formation and persistence of biofilms. Additionally, the presence of scale, rust, and sediment can provide a substrate for bacterial attachment and growth.5 The complexity of industrial cooling water systems, with their numerous components and pipelines, can also make it difficult to reach and remove biofilms in hard-to-reach areas. Finally,
Received: May 3, 2023 Accepted: June 26, 2023
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the presence of different types of microorganisms in biofilms can make it difficult to target and control specific bacterial species.
Regular monitoring of residual disinfectants such as chlorine or chloramines is crucial to ensure the efficacy of the disinfection process. Another strategy is to maintain the water quality throughout the distribution system by controlling the pH, temperature, and other physical and chemical parameters. These conditions play a vital role in promoting or inhibiting bacterial growth. Regular monitoring and control of these parameters help to ensure that the water remains free from harmful bacteria. Additionally, regular cleaning and flushing of the distribution pipelines can also help to remove any accumulated biofilms and bacteria. This is especially important in older pipelines where the accumulation of biofilms can become a significant problem. In some cases, the pipelines may need to be replaced to ensure that the water remains free from harmful bacteria.5
The aim of this mini-review is to provide an overview of the strategies and best practices for controlling biofilm in industrial cooling water systems. Specifically, this mini-review will discuss
the nature of biofilms and their composition, highlight the challenges they present in terms of control and removal, and provide an overview of the strategies and best practices used to prevent and control biofilm growth in industrial cooling water systems. The scope of this mini-review is to provide a concise summary of the most important factors to consider when managing biofilm growth in industrial cooling water systems, and to provide a useful resource for water treatment professionals looking to improve their knowledge and practices in this area. By adopting the best available technologies, such as maintaining a high level of residual disinfectant in the distribution system, controlling physical and chemical parameters, regular cleaning and flushing of distribution pipelines, and even pipeline replacement in some cases, biofilm growth in industrial cooling water systems can be minimized, and high-quality cooling water can be delivered to the industrial process sectors.
Figure 1.Circulation mapping of industrial cooling water systems.
Figure 2.Formation of biofilm in industrial cooling water system.
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2. FACTORS INFLUENCING BIOFILM GROWTH IN INDUSTRIAL COOLING WATER SYSTEM
2.1. Formation of Biofilm in Industrial Cooling Water System.The formation of biofilms in industrial cooling water systems is a complex process that involves the attachment and multiplication of microorganisms on surfaces in aquatic environments, including distribution system pipelines. Biofilms begin to form when planktonic bacteria come into contact with a surface, such as a pipe or tank wall, and attach to it (Figure 2). Once attached, the microorganisms begin to multiply and produce a matrix of extracellular polymeric substances (EPS), which is composed of various macromolecules and provides a protective layer for the microorganisms.
The attachment of microorganisms to surfaces is influenced by several factors, including the nature of the surface, the chemistry of the water, and the flow rate in the distribution system. For example, the accumulation of macromolecules at solid−liquid interfaces can promote the attachment of microorganisms to the surface, while a high flow rate in the distribution system can prevent attachment by removing planktonic microorganisms from the surface.
Once attached, the microorganisms produce EPS, which helps anchor them to the surface and may contribute to nutrient capture. The EPS matrix also provides a protective layer for the microorganisms, which can help shield them from environmental stressors such as fluctuations in temperature, pH, and nutrient availability. The EPS matrix also allows for the exchange of nutrients and metabolic byproducts between microorganisms, enabling them to form complex communities.
In addition to EPS production, the metabolic activity of the microorganisms within the biofilm can contribute to the growth and maintenance of the biofilm. For example, some microorganisms may produce enzymes that break down organic matter in the water, providing nutrients for other microorganisms within the biofilm. Other microorganisms may consume the waste products of neighboring microorganisms, allowing for a more efficient use of nutrients within the biofilm.
2.2. Microorganism Composition of Biofilms Indus- trial Cooling Water Systems.Biofilms are known to develop in areas of cooling water systems that are difficult to reach, such as dead-end pipes, tower packing surfaces, and areas with
low water flow. Cooling tower systems are particularly susceptible to biofilm contamination due to the presence of nutrients, dust, and complex piping. Biofilms are formed by the attachment of microorganisms to surfaces and subsequent multiplication to create a matrix of extracellular polymeric substances (EPS). The EPS matrix provides protection to microorganisms and helps in the exchange of nutrients and metabolic byproducts. Biofilms that form within industrial cooling water systems are composed of a diverse array of microorganisms, including bacteria, fungi, and protozoa. The predominant bacterial species found in biofilms are typically members of the Enterobacter genus, such as Enterobacter cloacae, Klebsiella, Citrobacter freundii, and Enterobacter agglomerans. These bacteria are capable of thriving in the unique microenvironments present within the pipes, where they multiply and attach to the surfaces to form a protective slime layer (Figure 3).
In addition to bacteria, fungi such as yeasts and molds can also be present in finished water and can colonize and multiply within the distribution system. These fungi are not typically pathogenic but can cause taste and odor issues for consumers.10 The presence of fungi within the industrial cooling water system can also contribute to the accumulation of organic matter and other substances that can have a significant impact on water quality.
Finally, nonpathogenic protozoa and other invertebrates may also be present in the biofilm. These microorganisms can play important roles in the functioning of the distribution system, such as participating in the cycling of nutrients and contributing to the formation of organic matter. The presence of these microorganisms, along with the other components of the biofilm, can have significant impacts on the quality and availability of cooling water, making it important to understand and manage the formation and development of biofilms in these systems.11
2.3. Factors Favor Biofilm Growth in Distribution Systems.Factors that favor biofilm growth include hydraulic effects, which can create low-flow areas that promote biofilm growth. Nutrient availability is also important, with carbon, nitrogen, and phosphorus being key nutrients for biofilm growth. Other sources of nutrients, such as organic matter and Figure 3.Composition of biofilms in industrial cooling water systems.
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metals, can also promote biofilm growth. Disinfection residual concentrations that are too low may allow biofilm growth to occur, while high levels of disinfectants can select for more resistant bacteria. Corrosion can also provide nutrients and a surface for biofilm attachment.1,12 Finally, sediment accumu- lation can create a substrate for biofilm growth and alter hydraulic conditions (Table 1).
3. DETECTION OF BIOFILM OCCURRENCE IN INDUSTRIAL COOLING WATER SYSTEMS
There are several methods for detecting the presence of biofilms, such as visual examination, microscopic examination, and biochemical assays (Table 2). Visual examination involves observing a slimy or discolored film on surfaces or in water.
Microscopic examination involves taking samples from surfaces or water and examining them under a microscope to look for the presence of biofilm structures or cells. Biochemical assays involve using enzyme assays or other tests to detect the presence of biofilm-specific markers, such as extracellular polymeric substances (EPS) or quorum-sensing molecules (Figure 4).
Another characteristic of biofilm problems is the availability of nutrients. Biofilms require nutrients, such as carbon, nitrogen, and phosphorus, to grow. The measurement of nutrient levels in the water or on pipe surfaces can provide an indication of the potential for biofilm growth. The presence of biofilms in the water can also change the chemistry of the water, which can lead to increased corrosion of pipes.
Corrosion is another characteristic of biofilm problems.
Biofilms can promote corrosion by creating localized areas of low oxygen and altering the chemistry of the water. Examining corrosion patterns can provide a clue to the presence of biofilms. Additionally, biofilms can release metabolic by- products, such as acids and enzymes that can increase the rate of corrosion.
Lastly, the hydrodynamics of the water can be a character- istic of biofilm problems. Biofilms are influenced by the flow and turbulence of the water. Measuring flow rates and monitoring for areas of low flow or stagnation can help identify potential areas for biofilm growth.17The flow of water can also impact the detachment of biofilms from surfaces and the dispersal of biofilm cells into the water.
4. BIOFILM CONTROL AND PREVENTION IN INDUSTRIAL COOLING WATER SYSTEMS
4.1. Methods and Technologies for Biofilm Control.
Biofilm formation is a persistent problem in water systems,
which can cause contamination and pose a threat to public health and industrial safety. Biofilms are complex communities of microorganisms that adhere to surfaces and form a protective environment for bacteria, viruses, and other harmful organisms to grow and proliferate. To effectively manage biofilm growth in cooling systems, a comprehensive approach is necessary. Companies should develop a detailed plan that includes regular system maintenance, water sampling, and a strategy for dealing with biofilm and bacteria. This may require the assistance of a specialist water treatment expert, such as Water Treatment Services, to develop a tailored cooling water treatment plan specific to the site’s plant and equipment. There are several methods and technologies available for controlling biofilm growth in water systems. These methods can be broadly classified into physical, chemical, and biological approaches (Table 3).
• Physical approaches involve the use of mechanical action to remove biofilms. This involves the use of physical methods such as high-pressure water jets, ultrasonic waves, and heat to disrupt and remove biofilms.
However, physical treatment may not be effective in removing all types of biofilms and can also damage equipment if not done correctly.
• Chemical approaches involve the use of chemical agents to remove or prevent biofilm growth. One of the most common strategies for biofilm control is chemical treatment. Biocides, such as chlorine or bromine, are commonly used for this purpose. However, the sticky secretions produced by bacteria make it difficult for traditional biocides to penetrate the outer layers of the biofilm. Biocides may only kill certain types of bacteria and can become ineffective over time as bacteria populations change. Therefore, it is important to use the appropriate biocide and to monitor its effectiveness regularly.
• Biological approaches involve the use of biological agents to remove or prevent biofilm growth. Examples of biological approaches include the use of bacteriophages and enzymes. Biological approaches can be effective in controlling biofilm growth, but they may require specialized equipment and expertise.
Each approach to biofilm control has its advantages and limitations. Physical approaches, such as mechanical scrubbing or high-pressure water jets, can effectively remove biofilms quickly, but they may risk damaging the underlying surface.
Chemical approaches, such as the use of biocides or Table 1. Summary of Biofilm Growth Influencing Factors
factors specific details and explanations for the factors that favor biofilm growth
hydraulic effects biofilms thrive in areas with low flow or stagnant water, which can occur due to hydraulic effects such as dead zones or eddies. In these areas,
biofilms have more time to attach to surfaces and accumulate nutrients.7
nutrient
availability (a) carbon: biofilms require a source of carbon for energy and growth. Carbon can be obtained from organic matter, such as decaying plant
material or human waste.
(b) nitrogen and phosphorus: nitrogen and phosphorus are essential macronutrients for biofilm growth. They can come from sources such as
fertilizers, animal waste, or human sewage.4
(c) other sources of nutrients: biofilms can also utilize other nutrients, such as metals, inorganic salts, and sulfur.
disinfection residual concentrations
disinfectants such as chlorine are often added to cooling water to kill harmful bacteria. However, if the residual concentration is too low, biofilms may be able to survive and grow. Conversely, high levels of disinfectants can select for more resistant bacteria and encourage biofilm growth.
corrosion corrosion can create pits and rough surfaces on pipes, which provide a substrate for biofilm attachment.12The corrosion process can also release
nutrients, such as iron or manganese that can stimulate biofilm growth.
sediment
accumulation sediment accumulation can provide a substrate for biofilm growth and also alter hydraulic conditions. In addition, sediments may contain
nutrients, such as organic matter or metals that can support biofilm growth.
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Table2.SummaryofApproachestoBiofilmControl detection methodmechanismtechnologyexamplesindicators visualexami- nationbiofilmsmaybevisibleasaslimyordiscoloredfilmonsurfacesorin watertypicallyinvolvetheuseofacameraorsimplemicroscopetocapture imagesofthesurfacesorwater.•changesinsurfacetexture,color,orglossiness •presenceofvisiblegrowthsorclustersofmicroorganisms. •fluorescentdyesorotherchemicalagentsmaybeusedtoenhancethe visibilityofbiofilmsunderspecificlightingconditions microscopic examinationsamplescanbetakenfromsurfacesorwaterandexaminedundera microscopetolookforthepresenceofbiofilmstructuresorcell(a)fluorescencemicroscopy:thistechniqueusesfluorescentdyesthat bindtobiofilmstructuresorcells,makingthemvisibleundera microscope.
•presenceofextracellularpolymericsubstances(EPS),whichformthe protectivematrixofthebiofilm (b)confocallaserscanningmicroscopy:thismethodusesalasertoscan thesampleatdifferentdepths,producinga3Dimageofthebiofilm structure. (c)scanningelectronmicroscopy:thistechniqueusesahigh-energy electronbeamtocreateanimageofthebiofilmsurface,providinga detailedviewofitsstructureandcomposition.
•presenceofmicrobialcellsthatmakeupthebiofilmcommunity (d)opticalcoherencetomography:thismethoduseslightwavestocreate imagesofthebiofilmstructureandthickness. biochemical assaysenzymeassaysorothertestscanbeusedtodetectthepresenceof biofilm-specificmarkers,suchasextracellularpolymericsubstances (EPS)orquorum-sensingmolecules
(a)enzymeassays:indicatorsintheleftcolumncanhelpinthedetectionandquantificationof biofilmsincoolingwater,whichcanbeusefulforpreventing biofilm-relatedissueslikefoulingandcorrosion.•β-galactosidaseassay:canbeusedtomeasuretheactivityof β-galactosidase,anenzymeproducedbysomebacteriainbiofilms.2 •alkalinephosphataseassay:canbeusedtodetecttheactivityofalkaline phosphatase,whichisproducedbysomebacteriainbiofilms. (b)EPSdetection: •totalcarbohydratecontent:EPSproducedbybiofilmscontains carbohydrates,someasuringthetotalcarbohydratecontentofcooling watercanindicatethepresenceofbiofilms.3 •Congoredbindingassay:Congoredisknowntobindtoamyloidfibers inEPS,sothisassaycanbeusedtodetectthepresenceofamyloidfibers andhence,biofilms. (c)Quorum-sensingmoleculedetection: •acyl-homoserinelactone(AHL)detection:somebacteriainbiofilmsuse AHLsassignalingmolecules,sodetectingAHLsincoolingwatercan indicatethepresenceofbiofilms. •autoinducer-2(AI-2)detection:AI-2isanothertypeofsignaling moleculeusedbysomebacteriainbiofilms,anddetectingitcanindicate thepresenceofbiofilms.
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disinfectants, can be effective in preventing biofilm growth, but prolonged use may lead to the development of bacterial resistance. Biological approaches, such as the use of bacteriophages or biofilm-disrupting enzymes, can offer targeted control of biofilm growth, but they often require specialized equipment and expertise.
To achieve optimal biofilm control, a combination of several strategies can be adopted. These strategies can be broadly classified into distribution system maintenance, reservoir
maintenance, corrosion control, disinfection practices, and nutrient reduction. In distribution system maintenance, regular flushing and pigging can effectively remove biofilms from pipelines, while pipe replacement can provide a long-term solution to persistent biofilm buildup.18 The implementation of these practices on a regular basis helps prevent the accumulation of sediment and debris that serve as breeding grounds for biofilm-forming bacteria.
Figure 4.Schematic of detection methodology of biofilm occurrence in industrial cooling water systems.
Table 3. Summary of Approaches to Biofilm Control
approach definition examples risk and opportunity
physical ap- proaches
use of mechanical action to remove biofilms, which may include ultrasonic cleaning, high-pressure cleaning, abrasive cleaning, etc.
(a) ultrasonic cleaning can remove biofilms from surfaces such as stainless steel and medical equipment.
(a) physical approaches can disrupt the biofilm matrix and damage the microbial cells to remove biofilms but can also damage the underlying surface and create opportunities for new biofilm growth.
(b) high-pressure cleaning with hot water and detergents can remove biofilms from surfaces such as pipelines and heat exchangers.
(b) specialized equipment is required for physical approaches and they may not be suitable for all water systems.
(c) abrasive cleaning using pumice-based cleaners can physically scrub off biofilms from dental unit waterlines.
chemical ap- proaches
use of chemical agents to remove or prevent biofilm growth. Examples of chemical approaches include the use of oxidizing agents like chlorine and ozone, and nonoxidizing agents like quaternary ammo- nium compounds (QACs) and acid-based cleaners.
(a) chlorine is used as a disinfectant in water treatment systems to control biofilm growth, and chlorine dioxide is effective in controlling biofilm growth in dairy processing equipment.
strong oxidizing agents can effectively remove biofilms and kill microorganisms but may be corrosive and require careful handling and dosing to prevent damage to water system components and development of bacterial resistance.
(b) quaternary ammonium compounds (QACs) are used as sanitizers in the food industry to control biofilm growth and are effective in controlling biofilm growth in a cheese process- ing plant.6
(c) acid-based cleaners are commonly used to remove mineral deposits and biofilms from surfaces such as pipelines and heat exchangers, and are effective in removing biofilms from dairy processing equipment.
biological approaches
use of biological agents to remove or prevent biofilm growth. Examples of biological approaches include the use of bacteriophages and enzymes.2
(a) bacteriophages are viruses that infect and kill specific bacteria and can be used to control biofilm growth by targeting the bacteria that form the biofilm. They are effective in controlling biofilm growth in a wastewater treatment plant.
(a) biological approaches can effectively control biofilm growth, but may require specialized equipment and expertise, careful selection, and monitoring to avoid unintended effects on the wider microbial community in the water system.9
(b) enzymes can be used to break down the extracellular matrix that holds the biofilm together.
(b) biofilm control is vital for maintaining water quality and requires a comprehensive approach to prevent biofilm formation and growth in water systems.13−16
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Preventive measures play a crucial role in controlling biofilm growth. Regular cleaning and maintenance of cooling systems, ensuring proper water flow and velocity, and avoiding the accumulation of sediment and debris are key preventive measures.19The use of materials that resist biofilm formation, such as certain types of plastics or coatings, can also be advantageous in preventing biofilm growth. In addition to the approaches mentioned, it is important to incorporate emerging strategies into the discussion. For instance, nanotechnology- based approaches, such as nanoenzymes, have shown promise in eradicating bacterial biofilms and should be considered as potential tools for biofilm control. In Lin et al. research, the group discusses the potential of catalytically active nanoma- terials as artificial enzymes for various applications, including biofilm removal. These nanomaterials possess enzyme-like activities and can exhibit enhanced catalytic properties compared to natural enzymes. They can act as catalysts in various reactions, including oxidation and reduction processes, which are crucial for biofilm removal. The findings also highlight the advantages of using catalytically active nanoma- terials, such as their stability, scalability, and tunable catalytic properties. They discuss the different types of nanomaterials, such as metal nanoparticles and metal-organic frameworks, and their potential applications in biofilm removal.20 In recent research by Wu et al., a novel method for eliminating drug- resistant bacteria using a single-copper-atom photocatalyst.
The photocatalyst is capable of generating reactive oxygen species (ROS) upon exposure to light. These ROS have strong oxidizing properties that can effectively kill bacteria, including those in biofilms. The authors describe the integrated catalytic cascade facilitated by the single-copper-atom photocatalyst, which involves the generation of ROS and subsequent oxidative damage to the bacterial cells. They demonstrate the efficacy of this approach in eliminating drug-resistant bacteria, highlighting its potential for biofilm removal and control. The study provides insights into the development of innovative strategies for combating antibiotic-resistant bacteria using photocatalytic materials.21
By adopting a comprehensive and multifaceted approach that combines different strategies and considers the advance- ments in the field, effective control of biofilms in industrial cooling water systems can be achieved.22
4.2. Management Strategies and Best Practices of Biofilm Control. Reservoir maintenance is another crucial component of biofilm control. Prior to use, reservoirs should be thoroughly rinsed, and the retention time of water in the reservoir should be limited. Adequate residuals should be maintained in the reservoirs, and they should be kept covered to prevent contamination. By adopting these practices, the occurrence of biofilm growth in water storage facilities can be reduced. Corrosion control strategies, such as the use of chemical inhibitors and adjusting pH levels, can prevent the development of localized areas of low oxygen and reduce the rate of biofilm growth.2 For instance, the use of orthophos- phate can be effective in reducing corrosion and biofilm formation. The use of orthophosphate has been shown to create a thin protective layer on the inside of the pipes, which reduces the accumulation of biofilms.
Appropriate disinfection practices are also critical for controlling biofilm growth. The use of alternate disinfectants or increasing the free chlorine residual can help control the growth of biofilms. For example, chlorine dioxide has been shown to be an effective disinfectant that can penetrate
biofilms and control the growth of bacteria. Reducing nutrient levels is another effective strategy for controlling biofilms.8By using activated carbon filters, mixed carbon/sand filters, or biologically activated filters, the nutrient levels in the water can be significantly reduced, thereby limiting the growth of biofilms. The use of these filters can remove organic matter and provide a physical barrier to prevent the colonization of bacteria.
Lastly, the implementation of the best available technologies, such as a wellhead protection program, proper distribution system maintenance, and filtration and disinfection, can help prevent the formation and growth of biofilms in water systems.10 By adopting a comprehensive and multifaceted approach to biofilm control, water treatment professionals can ensure the delivery of safe and clean water to consumers. In conclusion, the control of biofilm requires a combination of strategies, which should be tailored to specific water systems.
By adopting these strategies, water treatment professionals can reduce the occurrence of biofilms and ensure the delivery of high-quality water to consumers.
5. CONCLUSIONS
Effective control of biofilms in industrial cooling water systems necessitates a comprehensive and tailored approach that considers the specific characteristics of each water system.
Water treatment professionals need to carefully analyze and address factors that contribute to biofilm growth, employing suitable strategies to control and prevent their formation. By implementing these strategies, the delivery of safe and clean water to consumers can be ensured. However, further research is crucial to advance our understanding and refine the strategies for biofilm control in water systems.
To further enhance biofilm control, future research should focus on several key areas. First, exploring novel nano- technology-based approaches, such as the utilization of catalytically active nanomaterials or single-atom photocatalysts, holds promise for more effective and targeted biofilm removal.
Additionally, investigating the potential of emerging techni- ques, including the use of nanoenzymes or other advanced methods, could provide valuable insights into eradicating bacterial biofilms. Moreover, comprehensive studies on the long-term effectiveness and durability of different biofilm control strategies are essential to assess their sustainability and optimize their implementation.
Furthermore, investigating the interactions between biofilms and different materials used in industrial cooling water systems, such as specific types of plastics or coatings, can contribute to the development of materials that are inherently resistant to biofilm formation. Understanding the underlying mechanisms and biofilm dynamics will facilitate the design of more efficient prevention and control strategies.
In conclusion, ongoing research efforts should strive to advance our knowledge of biofilm control in industrial cooling water systems, exploring innovative approaches, assessing long- term effectiveness, and optimizing strategies tailored to specific water systems. By continuously improving our understanding and implementation of biofilm control measures, we can enhance water quality, mitigate health risks, and optimize the performance of industrial cooling processes.
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ASSOCIATED CONTENT Data Availability StatementThe data that support the findings of this study are available from the corresponding author upon reasonable request.
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AUTHOR INFORMATION Corresponding AuthorYuanzhe Li −Carbon Neutrality Research Lab, China Academy of Art, Hangzhou 310002, China; School of Materials Science&Engineering, Nanyang Technological University, Singapore 639798, Singapore; orcid.org/
0000-0001-7530-8286; Email:[email protected] Authors
Hening Wang−Faculty of Arts and Social Sciences, The University of Sydney, Sydney 2006, Australia
Haoyi Yang−NUS College of Design and Engineering, National University of Singapore, Singapore 118429, Singapore
Ken-An Lin−Corporate Social Innovation Program, Royal Roads University, Victoria, British Columbia V9B 5Y2, Canada
Tiancheng Shao−Carbon Neutrality Research Lab, China Academy of Art, Hangzhou 310002, China; Facultéde l’aménagement, Universitéde Montréal, Montréal, Québec H3T 1B9, Canada
James Hope −Carbon Neutrality Research Lab, China Academy of Art, Hangzhou 310002, China
Complete contact information is available at:
https://pubs.acs.org/10.1021/acsabm.3c00319 Author Contributions
Y.L. designed the guideline of the articles; H.W. and H.Y.
contributed to the drafting of material and experimental testing for individual section; H.Y. and H.W. provided the guideline for and participated in the review work for the draft; T.S.
compiled the writing and conducted the analysis; K.-A.L. and J.H. aligned the paper; and H.W. and H.Y. reviewed and provided corrections on the original draft.
Funding
This research was funded by Enerstay Sustainability Pte Ltd (Singapore) Grant Call (Call 1/2022) _SUST (Project ID CAA-2003), Singapore.
Notes
The authors declare no competing financial interest.
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ACS Applied Bio Materials www.acsabm.org Article
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