How to Reduce Fouling in a Cooling Tower

How to Reduce Fouling in a Cooling Tower 

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If you’ve ever walked outside on a hot day or exercised hard enough to feel warm, then you are familiar with the body’s natural tendency to sweat. By releasing hot water from your body in the form of sweat, your body is attempting to decrease your heightened body temperature. Basically, your body is releasing excess heat into the atmosphere to keep you cool off.  

This is the same mechanism behind industrial cooling towers.   

Cooling towers typically use water from open natural sources because of their abundance and reduced cost. But since the water from a lake or ocean contains tons of nutrients and microorganisms, sometimes these outside materials can build up and create fouling, which in turn can harm the internal structure and reduce the overall efficiency of the tower.  

In this blog post, we’ll take a closer look at the best ways to reduce fouling in cooling towers.  

Biofouling and Treatments  

A lot of the fouling that occurs can be considered “biofouling,” which refers to the buildup of living material, such as:  

  • Bacteria  
  • Algae  
  • Fungi  
  • Barnacles  
  • Mussels  

Biofouling can be reduced by periodically or continuously flushing the system with biocides. Biocides or antimicrobial chemicals are designed to kill organisms or prevent them from reproducing.  

Particulate Fouling and Treatments  

Sometimes fouling is caused not by organisms, but by particles suspended in water that enter through the water intake and settle in the system. This is controlled mainly by the water velocity (how quickly it is moving down through the tower) and the size of the particles in the system.  

Particulate matter is mainly made up of insoluble minerals, such as: 

  • Aluminum 
  • Iron 
  • Silt 
  • Clay 

This matter may enter as small molecules, but as the water is recirculated, it can coagulate (clump together) to a more troublesome size.  

There are several methods of dispersing particulate fouling, including:  

Filtration  

Filtering water before it recirculates can greatly reduce the amount of larger particulates entering the system, but may not be effective against fouling that forms and settles.  

High Water Velocity  

If your system can handle a higher velocity of water, this method can be effective against silt and clay deposits. Other foulants, such as aluminum and iron are “stickier” and may not be affected.  

Dispersants  

Dispersants work by attacking suspended particles and giving them a high electric charge, making them repulsive to each other. This method prevents the clumping of particulates and also reduces the attraction between particles and the structure.  

Surfactants  

Surfactants are basically soaps that work similarly to dispersants by reducing the electrostatic attraction between the surface of the system and the particles attached to it.  

Fouling Problems in Your Industrial Water System?  

Let Ecolink help you reduce and prevent fouling in your industrial equipment. Reach out to one of our knowledgeable experts to learn the best method and product for your needs! 

How to Reduce Fouling in a Heat Exchanger

How to Reduce Fouling in a Heat Exchanger

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Heat exchangers allow excess heat to be removed from a system by using large amounts of cool water. However, the water used is commonly taken from a natural source and thus contains a wide variety of minerals and living microorganisms—all of which can cause blockage in the system. 

This blockage and buildup is known as fouling or biofilm. Fouling can decrease the heat exchanger’s efficiency and effectiveness when left unattended and is extremely undesirable. In this blog post, we’ll take a closer look at how you can reduce fouling in a heat exchanger for good. 

Types of Fouling Common in Heat Exchangers  

There are numerous ways that buildup can accumulate, including:  

  • Corrosion  
  • Precipitate  
  • Freezing  
  • Particle  
  • Chemical Reaction  
  • Biofouling  

While these aren’t all the ways, they are the most common. Luckily, there are methods you can implement to reduce and prevent biofilm from forming in your heat exchanger or other water system. 

Ways to Reduce Fouling  

Antifouling (AF) Coatings   

AF coatings are often an effective way of preventing buildup in heat exchangers. However, in the past, AF coatings have been harmful to the surrounding environment, but now new technology has led to the development of nontoxic AF coatings.   

Biocide Treatments   

Biocide chemical additives are an effective method of controlling biofouling. However, if the water used in your heat exchanger originates and circulates through a natural source (like a lake or ocean), certain biocides may be harmful to the natural ecosystem.   

Heat Treatments  

Periodically heating the water that goes through your system to extreme temperatures may be effective against biofouling by freezing or precipitates. The hot water often kills microorganisms and may redissolve certain clogging materials.  

Pressure Treatments  

Occasionally submitting your system to increased water pressure (within safe engineering limits) will flush the system and remove some of the accumulated material.  

Ultraviolet (UV) Irradiation  

An effective disinfectant, UV exposure causes some of the nearest water molecules to split, creating unstable “hydroxyl radicals,” which can break up clumps of organic material, and kill microorganisms by changing their DNA.  

Electromagnetic Field Exposure  

Exposing your system to electromagnetic fields can increase the interaction of calcium and carbonate ions in the water, which reduces the tension forces in the water. This means that many microorganisms will have more difficulty sticking to the heat exchanger’s surfaces.  

Importance of Reducing Fouling  

Fouling can lead to many harmful decreases in productivity, both in the reduction of efficiency and the loss of time when the system must be shut down to be cleaned.  

It can also lead to the corrosion of metallic components, either through oxidation (like rust), or biological corrosion, which involves microorganisms damaging a system with the chemicals they produce.  

Often fouling (particularly biofouling) can cause heat exchangers to release much less heat. This is because the additional layer of clogging around the coils acts as a kind of insulator and prevents the surrounding water from absorbing all of the excess heat.  

Want to Reduce Fouling in Your Heat Exchanger?  

Depending on the scale and variety of heat exchangers you have, different antifouling methods may work better. At Ecolink, we are ready to help you find the best way to reduce biofouling in your system. Contact us today for a free consultation session! 

Biofouling and Biofilm Treatment Explained

Biofouling and Biofilm Treatment Explained

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Biofouling is the buildup of organic materials, typically small plants, microorganisms, or algae on submerged mechanical equipment. Biofilm, more specifically, is a thin slimy layer of bacteria that adheres to any surface but can appear in the same situations prone to biofouling.  

In industrial settings, it is important to control biofouling, as it can often decrease the efficiency of a system by clogging holes or reducing potential water flow.   

Luckily, biofouling isn’t permanent and can be removed using either physical or chemical cleaning methods—or a combination of both. If you do find yourself with a fouling problem, then read on to learn about the best biofilm treatment methods. 

Membrane Cleaning: Physical  

Physical methods of removing biofouling and biofilm include:  

Hydraulic Cleaning: A common technique where water is flushed forwards and backwards through the system under extreme pressure to loosen scum.  

Pneumatic Cleaning: Pneumatic refers to the use of air, including, air lifting, air bubbling and air scouring, all of which use pressurized air to knock off material.  

Ultrasound: Exposing the system to ultrasound can create cavities in the fouling material and disrupt the microorganisms, causing layers of the material to fall off.  

Electric Field Therapy: While also a method of preventing biomass from accumulating, exposing the system to electric fields may remove some of the gathered microorganisms.  

Membrane Cleaning: Chemical 

Utilizing a chemical method of cleaning typically involves killing the organisms that are attached to the mechanical surfaces, which will then allow them to be flushed out of the system. The following are examples of chemicals that can be used:  

Caustic chemicals –  NaOH, KOH, NHOH  

Acidic –  HCL, HNO3, H2SO4, H3PO4, citric acid, oxalic acid  

Surfactants (detergents) – alkyl sulphate, cetyl trimethyl ammonium bromide, sodium dodecyl sulphate  

Oxidants (disinfectants) –  NaOCl, H2O2, KMnO4  

Cleaning blends –  Ecolink’s Biofilm Buster  

Caustics, acids, and surfactants all work by increasing the solubility of organic chemicals found in most biofouling organisms, thus making them less “sticky” and allowing the water flowing through the system to capture and remove them.  

Other chemicals work by decreasing the electric attraction between the organic chemicals in the organisms, or by simply killing the organisms, causing them to release their hold from the system’s membranes. Surfactants, or detergents, are particularly important for biofilm treatment because they work to disrupt the attraction between the surface of the system and the organisms in the water directly next to them.   

Determining how well any of these methods work is done by measuring the difference in water flow through the impacted system. A combination of physical and chemical treatments is often needed.  

Need Industrial-Grade Chemicals for Biofouling and Biofilm Treatment? 

If you need help figuring out the best chemical approach to biofilm treatment, Ecolink is happy to connect with you. Our range of available chemicals and staff of knowledgeable experts will get your system back up and running at high capacity.  

Reach out to us today to receive a free quote and consultation session! 

What Is Biofouling Prevention?

What Is Biofouling Prevention?

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Biofouling refers to the unwanted build-up of biological materials, such as bacteria, algae, or other microorganisms on surfaces submerged in water. It occurs commonly in industrial settings, where water is pumped through a system, typically as a cooling mechanism. For cost reasons, the water used is often “open circulating,” meaning that it comes from an open body of water, and thus is host to numerous biological species.  

Biofouling can have serious implications for the efficiency and safety of an industrial system. However, there’s no need to worry. With the proper tools and prevention techniques, you can protect your system.  

How Can I Implement Biofouling Prevention?  

Treatments to prevent biological fouling can take many forms, including:  

Biocide Treatments: chemical additives that kill microorganisms  

UV Irradiation: exposing water to UV light will prevent organisms from reproducing  

Bacteria Inhibitors: certain chemicals will prevent bacteria from communicating, thus dissuading bacteria accumulation 

Structural Changes: replacing the materials of a structure with certain polymer blends, or coating them in hydrophobic paint will reduce the risk of fouling  

Why Should I Prevent Biofouling?  

Biofouling can have an extreme impact on the efficiency of an industrial system. If the structure affected is used to direct water flow, the added biomass can clog pathways, making the system less efficient.  

For cooling systems where the surrounding water is intended to draw heat out of the structure, accumulated biomass will act as a sort of insulator, and make heat transfer less viable. This could be very harmful in situations like nuclear power plants, where enormous coils direct the heat generated in nuclear fusion to a large source of water, allowing the system to remain at a stable temperature. In fact, nearly 4% of power station failures in the United States are caused by fouling.  

Biofouling can also cause damage to submerged equipment through bio-corrosion. Bio-corrosion occurs when organic chemicals created by the biomass on a certain structure will eat away at the material it is attached to, similar to how battery acid can corrode small electronics.  

Need Biofouling Prevention Help?  

At Ecolink, we are proud providers of industrial-grade chemicals that assist companies in their daily operations and with any issues they may have. 

 If you are interested in biofilm and biofouling prevention for your industrial water system, don’t hesitate to reach out! One of our knowledgeable experts will be happy to help you find the best solution for your needs! 

Biofouling Prevention Treatment

Biofouling Prevention Treatment

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If you’ve ever swam in a natural body of water, you may be familiar with the slimy greenish-brown scum that accumulates on most submerged objects. Water is full of bacteria, viruses, algae, and other microorganisms.  

Just like pond scum, the inside of industrial systems containing water is susceptible to organic growth. This undesirable growth, known as biofouling, can clog water flow and decrease efficiency. For this reason, biofouling prevention treatment is critical.  

Biocide Treatment  

Traditionally, a common practice for preventing biofouling has been to add biocides or antimicrobial chemicals to the water that is being flushed through the system. Antimicrobial chemicals are substances that excel at slowing the spread of or killing fungi, bacteria, and viruses, and are used in treatments for: 

  • Cooling water systems 
  • Industrial water tanks 
  • Heat exchangers 
  • & more 

However, different microorganisms respond differently to certain biocides/antimicrobials, so it is important to understand our enemy. Listed below are three factors that’ll determine which chemical you should use for preventing biofouling in your industrial water system: 

  1. The level of bioactivity 
  2. The pH 
  3. The temperature of the water 

While your answers to the above factors will determine the type of biocide you use, they’ll also determine the frequency with which you apply the biocide. 

Here are a few examples of common chemicals used as a biocide:  

  • Chlorine   
  • Chlorine Dioxide  
  • Chloramines  
  • Potassium Ferrate  
  • Ozone  
  • Iodine  
  • Hydrogen Peroxide  
  • Peracetic Acid  
  • Sodium Bisulphite  
  • Formaldehyde  
  • Glutaraldehyde  
  • Quaternary Ammonium  

Not all the chemicals listed above will work in every setting. Sometimes certain chemicals can create harmful byproducts, are unstable unless produced on-site, or may be destructive to certain industrial materials. For example, certain chloramines cannot be used for wastewater treatment because they may create carcinogens and are destructive to certain filtering membranes.   

Alternative Biofouling Prevention Treatments  

Luckily, there are alternative biofouling treatments that don’t involve high risks to human and environmental health. Here is a list of safer and greener treatments used to prevent biofouling in industrial settings:  

UV Radiation 

Though not a chemical additive, UV irradiation has also been used as a disinfectant in water treatment. UV exposure works by splitting some of the water molecules to create hydroxyl radicals (unstable “half-molecules”), which can split up bigger organic molecules and inhibit microbial growth by damaging their DNA.  

However, the efficiency of UV irradiation depends on the density of biomass and the ability to expose all the water, making it an expensive solution  

Nutrient Limitation  

Certain microorganisms feed on chemicals such as phosphorus and phosphate. Removing those chemicals from the water, using absorbents or electrochemical coagulation, may reduce the potential for fouling.  

Interruption of QS Signals  

Microorganisms use quorum sensing (QS) to communicate with each other. Several chemicals, including vanillin, furanone, and acylase can interrupt these signals, and deter microbial growth.  

Membrane Surface Modifications   

Sometimes the best method of controlling biofouling is to make changes to the surfaces which accumulate the most debris. This could mean making the membranes out of a blended polymer, coating the surface in a hydrophobic sealant, or including antimicrobial additives in the material.  

Looking for an Industrial-Grade Biofouling Prevention Treatment?  

Ecolink is ready to help you solve your biofouling problem before it even starts! Contact us today to learn what treatments may work best for you!