Cooling Tower Q&A

Chris King is the Industrial Disinfection Sales Director - EMEA at Evoqua Water Technologies.  When he is not sampling wines of the world or basking on deserted beaches, he is driving innovation and leading growth in industrial water solutions across a range of market sectors.

We sat down with him to take a closer look at the types of application solutions Evoqua supplies for commercial, facilities and industrial customers.

Q. What role do cooling towers play in an industrial context?

Various industries including datacentres, commercial building and facilities maintenance utilize cooling towers to maintain heat transfer and enable process heat removal. In commercial or building applications, cooling towers are utilised to ‘comfort cool’ the people who work in them.

Q. What are the types of problems that clients come to you with?

There are really only four main water treatment issues that we deal with: biological contamination, corrosion, fouling and scaling.  They are issues mainly because they reduce energy efficiency, which means more electricity to do the same job and increased overheads as a result.

Q. Can you tell us more about what causes these issues?

Wherever cooling towers are installed are usually hot and humid places, ideal for the growth of unwanted bacteria.  These bacteria eventually form a thin film we call a biofilm inside the equipment which reduces thermal efficiency.  These bacteria can be dangerous for staff working in the facility, and are certainly not great for the efficiency of your cooling tower.

Corrosion and leaks are the other thing, especially in closed loop systems.  A cooling system that is not maintained is prone to corrosion caused by air, sodium and other chemicals that are found in our water supplies.   Once the metal starts to corrode, that’s when leaks happen.

In terms of fouling, cooling surfaces or pipes often get clogged with debris, dirt and dust. When water can’t pass through the heat exchanger, the air doesn’t cool which means the system has to work harder, using more electricity in the process.

The build-up of minerals in the water we use in the cooling towers can contribute to the excessive creation of deposits like calcium which lead to a reduction in heat transfer efficiencies and increased operating and maintenance costs.  That’s what we call scaling.

Q. What water cooling treatment solutions does Evoqua offer?

In EMEA, Evoqua offers a range of disinfection products to help solve the complex issues around cooling tower disinfection.

Our products include UV disinfection systems, chlorine dioxide generation, onsite hypochlorite generation, gas chlorination and ozone, meaning we really do have the depth of portfolio to match your treatment need to the best technology.

We also offer filtration solutions to remove suspended solids and control biological growth in the recirculating water stream. These filtration solutions, deployed either side stream or full flow, support reducing water make up required to keep the cooling system running efficiently.

By deploying our products in your system, we will allow industrial plants to run more sustainably by reducing energy and chemical consumption, saving on electricity and lowering costly overheads.

Q. What are the key benefits of an Evoqua solution?

There’s no doubt that our water-cooling treatment solutions do exactly what they should do: improve system efficiency, minimise annual cleanings, boost the effectiveness of chemical programmes, support microbiological control, and from a management perspective, significantly reduce overheads.

But what you also get when you opt for an Evoqua solution is the expert consultancy that comes as part and parcel of our sales team.  We challenge ourselves to really understand the needs of your business, and collaborate with you to get those needs met.  Our multi-technology portfolio means that we will always match the right technology to your application – and provide you with the product to solve your challenges. With a comprehensive service and aftermarket capability, we are never going to just sell you the equipment and disappear.

Q. Can you tell us what areas you specialise in?

Evoqua globally has about 100 years’ experience as the trusted advisor to 38,000 municipal, industrial and recreational customers.  So, we have a pretty broad repertoire.   The industrial markets we cover include food & beverage, healthcare, microelectronics, pharma, power generation, refining and chemicals, commercial, facilities and datacentres.

Due to the pandemic and the whole world suddenly needing to work and school and be entertained from home, growth in the latter is really strong at the moment and a core focus for our team.

Q. Could we talk briefly about individual disinfection and filtration systems & how they compare?

At Evoqua, we are lucky enough to have a depth of portfolio that allows us to make an informed decision based on needs of customer.  It’s totally dependent on the situation, environment and specific needs of the client.

1. Chlorine dioxide generators deliver all the pre-oxidation and disinfection benefits of chlorine dioxide with safety and efficiency in mind
2. In chemistry-controlled environments, disinfection process analysers and controllers provide compliance with health, safety and regulatory standards, optimise process efficiency and minimise chemical overdosing to maintain customer satisfaction and reduce operating costs
3. OSEC® On-Site Hypochlorite systems safely generate sodium hypochlorite on-demand, using only salt, water and power. With over 30 years of success, this in-situ product works well across municipal, aquatics and industrial markets
4. UV is used for disinfection and removal of organic and inorganic contaminants, including chlorine, ozone and total organic carbon. Key benefits include low maintenance and running costs without the need for large scale storage, handling or transportation of bulk chemicals
5. Chlorine gas has been the predominant chemical for the disinfection of water for over 100 years. Using a remote vacuum-operated gas feeder, a chlorine solution is prepared on-site by dosing the chlorine gas into the process water – both safe and economical
6. VAF™ Screen Filters are automatic self-cleaning screen filters for removal of suspended solids which provide cost-effective, efficient, and space-saving solutions to reduce water waste and limit maintenance
7. High-Efficiency Microsand Filters allow the unit to operate at filtration rates of up to four times greater than those of traditional media filters, while filtering 10-50 times finer - reducing water consumption, saving energy, reducing chemical costs, and requiring minimal maintenance.

For us, the goal is to ensure that cooling towers run super-efficiently to reduce energy and chemical consumption, save on electricity and lower the total cost of doing business.  The last thing that clients want is an outage that means downtime - costing money, causing headaches and damaging brand reputation.

Connect with Chris King on LinkedIn.