An effective, environmentally secure solution to biofouling, helping to save millions for the industry through better heat transfer efficiency and reduced maintenance costs.
Cooling towers, seawater intakes, condensers and distribution pipework are all susceptible to the build-up of biological fouling on their surfaces that lead to increased energy, maintenance and compliance costs. This fouling cannot be removed easily by traditional biocide treatments such as chlorination.
Scotmas ClO2 systems combine the disinfecting power of chlorine dioxide with state of the art control and monitoring systems to minimise chemical consumption, environmental impact and corrosion risk. Our systems are installed on systems ranging from small pack cooling towers through to power station seawater intakes, and paper mill water handling applications.
Scotmas can work with your on-site water specialists to deliver a system that enhances your site performance, bottom line, and environmental compliance.
Recirculating Cooling Towers
Chlorine Dioxide solutions from Scotmas offer operators a unique opportunity to achieve cost savings while protecting the environment

- Cooling tower operators must ensure safety from bacterial infections such as Legionella, whilst also being under pressure to reduce operating costs.
- Biofilm build up on condenser plates and cooling tower packs acts as an insulating layer, slowing down heat transfer, reducing water flow and increasing pumping costs, as well as being a harbour for dangerous legionella bacteria which live alongside scale, pseudomonas and other bacteria in a slimy layer found on plate surfaces and pipework.
- Biofilm also poses a threat to asset integrity. Bacteria at the base layer of the film can create an anaerobic, corrosive environment and can feed from plastic and metal structures, passing on nutrients to other nearby bacteria. This phenomena, called biocorrosion regularly leads to pack collapses and poor water flow throughout the tower, requiring expensive and disruptive pack changes and increased energy costs to pump water around the tower.
- Scotmas Chlorine Dioxide solutions for cooling towers are designed to minimise these risks. Our online, fully automatic dosing systems add a controlled amount of chlorine dioxide sufficient to remove biofilm leading, keeping heat transfer surfaces clean and free of biofilm. Frictional losses and pumping costs are reduced and there are significant improvements in ∆T.
- Applied by your water treatment professional as part of a program of cooling tower hygiene, Scotmas Chlorine Dioxide solutions can be used in the smallest forced draft towers and wet chillers, typically used in the injection moulding and plastics extrusion industry, through to the largest industrial cooling networks such as found in power stations and petrochemical refineries.
Seawater Cooling
Molluscs, barnacles and filamentous algae can cause significant energy losses when allowed to grow unchecked. Maintain process efficiency with ClO2

- Chlorine, whether from gas cylinders, hypochlorite or electrochlorination, is a widely used disinfectant for controlling the growth of marine organisms in industrial cooling systems. Surprisingly, chlorine is relatively ineffective at high pH’s, and much of the actual disinfection is carried out instead by displaced bromine which is also present in the seawater. Chlorine Dioxide is effective at high pH levels and can successfully tackle zebra mollusc problems in pipework.
- Chlorine Dioxide applications for seawater can improve energy efficiency in cooling water systems and reduce the environmental impact from chlorinated by-products, associated with chlorine disinfectants.
- As chlorine gas and hypochlorite treatments are decommissioned, electrochlorination is often promoted as a potential alternative treatment. However, the power costs and depreciation / maintenance costs of seawater electrochlorination systems is considerably higher than the equivalent Chlorine Dioxide approach, which offers a more effective biocidal treatment with minimal environmental impact.
- Scotmas build and install skid mounted, containerised and mobile Chlorine Dioxide generation systems suitable for the largest seawater cooling systems, installed in power stations, chemical works and refineries / terminals. Our technical and engineering teams are experienced in dealing with the most complex installations, including those in hazardous (ATEX) environments and geographies. Scotmas also offer the best possible regulatory support based on our unparalleled worldwide experience.
Industrial Wastewater
As well as being a powerful disinfectant, ClO2 can also be used to oxidise challenging wastewater pollutants such as cyanide, phenols, sulphides, iron and manganese from industrial wastewater streams

- Where low levels of persistent industrial residuals are found in wastewater, Chlorine Dioxide can often strike the ideal balance between a low cost, environmentally friendly treatment for these waste streams, when compared with chemical and capital intensive programs based on peroxide and/or UV.
- Used as a complement to advanced biological wastewater treatment systems that are designed to treat the bulk of the waste stream, chlorine dioxide can be used as a polishing agent for the final stream. Unlike chlorine based treatments, ClO2 does not form complex chlorinated by-products, and can often be discharged to watercourses without dechlorination, eventually degrading to salt. Unlike peroxide based systems, no catalysts or pH adjustments are required, with most ClO2 action taking place within the normal pH range.
- Scotmas have developed advanced wastewater treatment systems for chemical processing plants, mining and refinery operations, and have the in house chemistry, microbiology and engineering talents to deliver a system suitable for your individual requirements, and with the data logging and environmental monitoring systems demanded by your regulators.
Odour Control & Wastewater Treatment
Chlorine Dioxide is effective across a broad pH range, and unlike chlorine will oxidise a number of odour causing compounds without forming toxic chlorinated by-products

- Effectively controlling industrial odour emissions requires a deep understanding of the upstream process, and any variability that might occur. Often, a combination of alkaline and basic scrubbing systems, and/or barrier misting systems are required to achieve complete control.
- Chlorine Dioxide can form an important part of this control system. Scotmas work with leading manufacturers of scrubber and barrier mists systems to integrate effective chlorine dioxide treatments into the treatment chain.
- Chlorine Dioxide is particularly effective against sulphides, mercaptans, secondary and tertiary amines where its powerful, non-chlorinating oxidative action oxidises the compound to non-odour producing components, without producing chlorinated organic compounds that are so hazardous in wastewater discharges.
- Chlorine Dioxide can be added to once through and recirculating scrubber systems easily and cheaply using our Alpha dosing systems, or even directly without a generation system to recirculating acidic systems.
- In temporary barrier misting systems, Chlorine Dioxide can again be applied as a simple tablet to the feed bowser, or via a simple continuous dosing system. Scotmas provide simple colour change dip test kits to help you ensure that Chlorine Dioxide is being delivered efficiently and safely to your system.