• Twitter
  • Facebook
  • LinkedIn
  • Mail
  • Call Me Back
  • About
  • Knowledge
📞 Call us on 0330 223 31 31
  • 0Shopping Cart
Water Treatment Services
  • Home
  • Water
    • Applications
      • Boiler Water Treatment
      • Cooling Water Treatment
      • Closed Loop Water Treatment
      • Legionella Control
    • Services
      • Cooling Tower Cleaning
      • Cooling Tower Maintenance
      • Chlorine Dioxide Water Treatment
      • Commercial Water Softeners
      • Pre-Commission Cleaning
      • Tank Reline & Repair
      • TMV Servicing
      • Water Chlorination & Disinfection
      • Water Leak Detection
      • Water Testing
        • Drinking Water Testing
        • Metals Testing
        • Pool Water Testing
        • BSRIA Closed System Testing
        • SDI Testing & Analysis
        • Trade Effluent Testing
    • Training
      • Water Treatment Training
      • Basic Chemistry of Water
      • Industrial Treatment
      • Pre-Treatment
      • Boiler Treatment
      • Cooling Systems
      • Closed Systems
      • Wastewater Training
      • Advanced Treatments
      • Training Dates 2021
  • Wastewater
    • Metals Testing
    • Trade Effluent Testing
    • Wastewater Training
  • Air
    • Ductwork Cleaning
    • Indoor Air Quality
    • Local Exhaust Ventilation
    • Mould Testing
  • Energy
  • Legionella
    • Legionella Risk Assessment
    • Legionella Training Courses
      • Legionella Awareness Training
      • Responsible Person Training
      • Water Hygiene Awareness
      • Pseudomonas Training
      • Training Dates 2021
    • Legionella Testing
  • Contact
  • Search
  • Menu Menu
You are here: Home1 / Knowledge2 / Energy3 / Treating Cooling Towers to Control Scale, Corrosion & Microbiological...
Treating cooling towers to control scale, corrosion & fouling

Treating Cooling Towers to Control Scale, Corrosion & Microbiological Growth

In the UK the Health and Safety Executives Approved Code of Practice ACOP L8 and Guidance document HSG274 Part 1 dealing with the control of Legionella bacteria in cooling water systems describe issues which can influence the effectiveness of a water treatment programme developed to control legionella. These issues include the control of:

  • Corrosion

  • Scale formation

  • Fouling

  • Microbiological activity

Each of these elements are interrelated and failure to control any one of them may lead to all occurring simultaneously, resulting in an environment that encourages the growth of legionella.

Developing a cooling water treatment programme

When developing an effective monitoring and water treatment control programme, it should be remembered that scale formation and fouling are continuous physico-chemical processes, and inhibitors to control such processes should be added to the water system on a continual basis.

  • Learn more about the HSE’s ACOP L8 here

Treating cooling towers

All water treatment chemicals dosed to cooling tower systems should be automated to ensure precise and continuous protection is achieved. All components of the treatment programme should preferably be dosed using a high quality pump or eductor (sometimes referred to as an ejector) system, or by a suitable halogen dosing system such as a brominator. This will help to minimise the health and safety risks to operators and ensure that dosing frequencies and rates of chemical application are maintained as recommended.

The importance of dosage and control equipment in the overall control of water systems should never be underestimated.

Automating the water treatment process

Installing and using automated monitoring and control equipment in water systems is a major component in the control of legionella bacteria in water systems. The type of equipment used in water systems is varied and dependent upon the type of system to be treated.

Typically a water treatment programme for a cooling tower would require the use of a dosing system to accurately meter the chemical scale and corrosion inhibitors into the system at a rate proportional to the water make-up.

The level of concentration of salts in the cooling water is usually measured by conductivity and this measurement linked to a solenoid valve to actuate a controlled bleed-off of water from the cooling system. There may also need to be a polymeric dispersant added to the treatment programme in order to control fouling by suspended solids. Additionally, and importantly there should always be some form of automated biocide addition to the system.

Using biocides to control microbiological activity

Biocide addition and the equipment needed to treat cooling towers effectively will typically depend on the approach used, and this is usually a simple decision linked to the type of biocide recommended by your water treatment specialist.

Oxidising biocides, such as Chlorine, Bromine, Chlorine Dioxide, Peroxides or Ozone are usually dosed by specifically designed equipment. This equipment is usually controlled by measuring the reserve of chemical in the cooling water, either by direct species measurement or by the use of a REDOX measuring device to actuate or switch off the dosing equipment.

With this biocide approach it is possible to maintain conditions in the water system with biocide present at all times and to continually measure and record the reserve. This method of cooling tower water treatment has become increasingly popular over the last 20 years.

Using alternating biocides

Non-oxidising biocides are usually added to a water system using a twin dosage arrangement that is controlled by a timer. As an example, the timer would be set to add biocide X for 3 doses and an alternating biocide Y, would be added every 4th dose. Such an alternating approach helps to minimise the risk of micro-organisms developing a resistance to the chemical species used as part of the control programme.

Using water softeners to reduce scale

In addition to control equipment the use of water softeners has become more prevalent as a method of keeping heat exchange surfaces free from scale formation. This has the additional benefit of reducing areas for pathogenic microorganisms to hide-out and proliferate.

In the fight to control Legionella bacteria, dosing and control equipment is recognised as a well established and proven part of all good water treatment programmes, helping to significantly reduce the inherent risks of operating water systems.

Cooling tower and legionella control specialists

Water Treatment Services offer a comprehensive range of legionella control and environmental solutions for the control of Legionella bacteria including water treatment solutions, water analysis and legionella risk assessments.

With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained engineers, in-field water treatment service specialists and technicians we can offer cost effective legionella risk management, ACOP L8 compliance and engineering support services throughout the UK and Ireland.

Contact Us Today

Further reading…

More information about the treatment of cooling water systems … learn more here →

Tags: ACOP L8, Controlling Legionella, HSG274, legionella, legionnaires disease
You might also like
Expert Courses for Legionella Awareness, Responsible Person & Duty Holders Expert Courses for Legionella Awareness, Responsible Person & Duty Holders
Hot Tub Legionnaires’ disease Deaths at UK DIY Store Lead to Manslaughter Charges
Sampling Potable Water for Legionella Bacteria: Legionnaires Disease Outbreaks Sampling Potable Water for Legionella Bacteria – Legionnaires Disease Outbreaks
Legionella Testing and Water Sampling: Legionnaires Outbreak Investigations Legionella Testing and Sampling During Legionnaires’ Outbreak Investigations
Expansion vessels and legionella risks Guide to Expansion Vessels & Legionella Risks
Legionella bacteria What is Legionella Bacteria?
Adiabatic cooling systems and open evaporative cooling towers compared Adiabatic Cooling Systems & Open Evaporative Cooling Towers Compared
Using Chlorine Dioxide to Treat Water, Wastewater & Effluent Using Chlorine Dioxide to Treat Water, Wastewater & Industrial Effluents

Search…

What’s New

  • Health Effects of Drinking Softened Water

    Health Effects of Drinking Softened Water

    This article looks at the potential health effects of …
  • How to Stop Pipes Freezing

    How to Stop Pipes Freezing

    Whether plumbing systems are used at home or at …
  • What is Trade Effluent?

    What is Trade Effluent?

    Trade effluent is defined as any liquid waste which …
  • Troubleshooting Problematic Closed Water Systems

    Troubleshooting Problematic Closed Water Systems

    This technical troubleshooting guide looks at closed water systems, …
  • District Heating – Heat Distribution Networks Explained

    District Heating – Heat Distribution Networks Explained

    This technical guide explains the concept of district heating …
  • Legionella Guidance for Landlords

    Legionella Guidance for Landlords

    In the UK landlords have a legal responsibility to …

REVIEWS

4.8
Rated 4.8 out of 5
Water Treatment Services is rated 4.8 out of 5 stars (based on 94 reviews)
Read our reviews

Free Newsletter

Receive exciting features, news, latest research and special offers! Just add your email address and we'll do the rest.

Contact us

Water Treatment Services

[email protected]

Tel: 0330 223 31 31

© Copyright 2021 - EDG Ltd. Operating as Water Treatment Services
  • Twitter
  • Facebook
  • LinkedIn
  • Mail
  • Home
  • About
  • Careers
  • Privacy
  • Environment
  • Reviews
  • Sitemap
Controlling Legionella in Hot & Cold Water Systems Controlling legionella in hot and cold water systems E.coli water testing for hot tubs and swimming pools What is E.Coli & Why Testing Hot Tubs & Swimming Pools is a Good ...
Scroll to top

WTS response to Covid-19. As a responsible organisation we have robust Business Continuity Plans in place to ensure business as usual whatever the circumstance. In response to Covid-19, our aim is to ensure continued operations whilst protecting both our people and our clients. To this end we have initiated a number of practical measures that will allow us to continue to support our clients in the most appropriate way. Rest assured that we are making every effort to prevent or minimise any impact on our services during this public health challenge.

OK

Cookie and Privacy Settings



How we use cookies

We may request cookies to be set on your device. We use cookies to let us know when you visit our websites, how you interact with us, to enrich your user experience, and to customize your relationship with our website.

Click on the different category headings to find out more. You can also change some of your preferences. Note that blocking some types of cookies may impact your experience on our websites and the services we are able to offer.

Essential Website Cookies

These cookies are strictly necessary to provide you with services available through our website and to use some of its features.

Because these cookies are strictly necessary to deliver the website, refuseing them will have impact how our site functions. You always can block or delete cookies by changing your browser settings and force blocking all cookies on this website. But this will always prompt you to accept/refuse cookies when revisiting our site.

We fully respect if you want to refuse cookies but to avoid asking you again and again kindly allow us to store a cookie for that. You are free to opt out any time or opt in for other cookies to get a better experience. If you refuse cookies we will remove all set cookies in our domain.

We provide you with a list of stored cookies on your computer in our domain so you can check what we stored. Due to security reasons we are not able to show or modify cookies from other domains. You can check these in your browser security settings.

Google Analytics Cookies

These cookies collect information that is used either in aggregate form to help us understand how our website is being used or how effective our marketing campaigns are, or to help us customize our website and application for you in order to enhance your experience.

If you do not want that we track your visit to our site you can disable tracking in your browser here:

Other external services

We also use different external services like Google Webfonts, Google Maps, and external Video providers. Since these providers may collect personal data like your IP address we allow you to block them here. Please be aware that this might heavily reduce the functionality and appearance of our site. Changes will take effect once you reload the page.

Google Webfont Settings:

Google Map Settings:

Google reCaptcha Settings:

Vimeo and Youtube video embeds:

Other cookies

The following cookies are also needed - You can choose if you want to allow them:

Privacy Policy

You can read about our cookies and privacy settings in detail on our Privacy Policy Page.

Privacy
Accept settingsHide notification only