“In the world of sawmills, the Waren effect has been shown to provide up to 25 percent reduction in energy use in dryer boiler circuits. We have achieved similar savings in boiler plants, power plants and in flue-gas condensation plants,” says Anders Larsson, CEO of tech company Waren International AB. “It is important to achieve the Waren effect and keep it!”
Is the Waren effect a magic wand? “It is not about magic. Instead it is about systematically working with the correct fluid chemistry to prevent corrosion and leaks. As soon as you fill an energy or climate-related plant with water the pipes will start to corrode. This reduces energy efficiency, promotes corrosion and increases the cost of service and maintenance,” continues Larsson. “The Waren effect is thus a concept for liquid treatment that provides protection against corrosion, microorganisms, coatings, oxygen and carbon dioxide.”
Correct fluid chemistry is the key
Larsson shows three glass bottles containing water and steel wool (iron). In the first bottle, steel wool has corroded for a year and the water is brown and rusty colored. In the second bottle, steel wool has only been submerged for a day but corrosion has begun and is visible. The third bottle contains water treated with the Waren effect and despite the presence of steel wool is still clear. “You can imagine how corrosion affects the pipes and the systems that come in contact with the brown water. Simple water treatment can save large sums of money in terms of energy efficiency and reduced maintenance,” says Larsson.
“With detailed analysis of the liquids in the system, we can determine the condition of a plant. Factors to consider include the use of antifreeze agents like glycols that get broken down into acids and carbon dioxide, creating inefficiencies. Add corrosion, mildew and bacteria, and the system may be using more energy than it recovers. Corrosion forms large amounts of particles and sludge long before it pokes holes in the systems, clogging and blocking valves compromising control and regulation systems. “Our method prevents corrosion and coatings, and dissolves already formed deposits in boilers, pipes, heat exchangers and cooling systems.”
The Waren effect requires several steps:
- Mapping and analysis. All components of the energy plant are reviewed and risk assessment is based on fluid analysis. Fluid analysis is conducted by Waren’s chemists or by independent laboratories.
- Roadmap. After a status update comes design suggestions. This involves corrosion risk assessment and identifying cost-effective measures for improving energy efficiency.
- Treatment. This includes everything from cleaning heat exchangers to complete water-borne system treatments, or systems with different types of antifreeze media.
- Waren certificates. Upon achieving the Waren effect, customers can choose to certify the facility as a way to maintain long-term effects.
Better protection with proprietary glycol
In 2014, the company presented its Warengy product series. “The new series includes the Warengy ETA and the Warengy PPA products that provide a very high safety factor against corrosion, bacteria and the chemical constituents consisting mono ethylene and polypropylene glycol,” says Larsson.
“From an environmental perspective, the product Waren BioTransfer is of particular interest and is produced exclusively from renewable raw materials (bio-based propane). Its production, process, and energy consumption is about 40 percent lower compared with glycols produced from fossil raw materials. The product also has several physical and chemical advantages such as low viscosity, increased freeze protection at higher concentrations and high thermal stability. The new products have been thoroughly tested in accordance with ASTM D1384-05 industry standard in a wide range of different materials. They perform excellently in tests with metal losses far below acceptable limits,” says Larsson.
The article was published in March 2015