Edited by Eamonn Ryan
SAIRAC organised one of its regular factory tours late last year, this time to Evapco’s premises in Isando, Johannesburg. The following presentation was delivered by MD Andre van der Merwe.
Gregory Grobelaar, SAIRAC Johannesburg Centre chairman and by Evapco MD Andre van der Merwe. All images supplied by RACA Journal.
In 1982, Evapco took its first step towards global expansion by establishing its presence in South Africa. Last year marked a significant milestone for the company as it celebrated its 40th anniversary in South Africa, highlighting its enduring success in the region. Evapco first expanded into Italy in 1979 and then South Africa. Over the years, Evapco has strategically diversified its product portfolio, evolving from a company solely focused on evaporative cooling products such as cooling towers, evaporative condensers, and fluid coolers, to offering a complete range of wet, dry and hybrid adiabatic coolers. Moreover, the company has ventured into various other product segments. Today, Evapco boasts nearly a dozen facilities across the US, four facilities in Europe, four facilities in China, and one in each of South America, Australia and South Africa.
The global firm does prolific research and development (R&D), while the South Africa operation is a full licensee of Evapco that contributes financially to that R&D. The company boasts cutting-edge facilities, including thermal laboratories equipped with advanced testing capabilities. While modern technology has introduced tools like computerised fluid dynamics (CFD) for testing and rating purposes, Evapco firmly believes that full-scale testing remains the most accurate measure of product performance for the creation of top-quality products.
Various completed units ready for shipment.
Evapco’s products not only meet high standards but also cater to specific market requirements. For instance, the US, particularly California, imposes stringent seismic testing regulations, ensuring safety and reliability during seismic events. Evapco readily complies with these demanding specifications, demonstrating its commitment to providing exceptional products. Furthermore, Evapco recognises the importance of meeting environmental standards. Green initiatives have gained significant traction across the globe, with California being a pioneer in this regard. The state’s susceptibility to earthquakes and water shortage issues has led to the implementation of strict regulations and significant rebates for green building designs. While South Africa has embraced the concept of green buildings, the lack of financial incentives has limited widespread adoption. In contrast, cities like Melbourne in Australia have seen a surge in green buildings due to attractive tax benefits and rebates.
With climate change becoming increasingly evident, Evapco acknowledges the need to address environmental concerns. As extreme weather events continue to occur worldwide, it is crucial for manufacturers to evaluate their impact and contribute towards sustainable solutions. The company urges organisations to prioritise the development of eco-friendly products and technologies to mitigate the effects of climate change.
The various types of Evapco cooling systems – known as the full Spectrum of Cooling Products – available include:
- Evaporative fluid cooler or evaporative condenser: This product range represents the standard for Evapco cooling It operates as a closed-circuit fluid cooler, ensuring optimal efficiency for your cooling needs.
- Hybrid fluid cooler or Hybrid Condenser: Evapco also offers a hybrid fluid cooler, which combines a dry coil and a wet This configuration optimises the system’s operation and provides improved performance for your cooling requirements. It offers the best combination of both water and energy savings.
- Full air cooled units: The next step in the evolution of Evapco cooling systems is the full air cooled These units operate without the need for water, making them straightforward and easy to understand.
- Air cooled units with adiabatic pads: One of the most interesting options offered by Evapco is the air cooled unit with adiabatic These units provide enhanced cooling performance by utilising adiabatic pads. Essentially this is a dry cooler with wet trim.
A group shot of the attendees at the Evapco site visit.
Understanding the principle of operation of evaporative condensers is crucial in comparing different Evapco cooling systems. The coil in these systems allows for the efficient introduction of refrigerant, resulting in 100% wet conditions throughout the year. Comparing the water consumption of various Evapco cooling systems is essential. The suggested rule of thumb for evaporative systems is that 85% of the process involves latent heat rejection, while 15% is related to sensible heat rejection.
Each Evapco cooling system requires consideration of factors such as evaporation rate, drift loss and bleed. Drift loss depends on the efficiency of drift eliminators, and Evapco systems are designed to achieve high efficiency in this regard. Additionally, working with a qualified water treatment professional can help ensure the appropriate cycles of concentration are maintained.
The hybrid cooler, featuring a combination of dry and wet modes of operation, offers significant water and energy savings as it fluctuates between different modes based on ambient conditions. This allows for a more efficient and sustainable cooling solution.
Dry coolers operate solely based on the ambient dry bulb temperature. While they offer zero water consumption, they are restricted to higher operating fluid temperatures. Their physical size and weight may also pose challenges during retrofitting and installation. To offer some needed temperature efficiency to the Dry Coolers the coolers can be supplemented with Adiabatic Pads. Evapco’s adiabatic dry cooler offers substantial water savings compared to the wet cooler, making it a desirable solution in a world facing climate change, high water costs and stricter regulations. It is a popular option for companies unable to get water quota in some municipalities.
Eco Aire series dry coolers in final assembly.
Regarding the advantages of Evapco’s adiabatic condensers compared to air-cooled ones, the adiabatic condensers have lower installed power, a smaller footprint and higher capacity. This means they can provide more efficient cooling in a compact design. The adiabatic pads are installed on the outside of the condenser unit. Additionally, Evapco offers a free cooling system with solenoid valves that activate the pads and introduce water when needed.
Eco Aire Series Dry Cooler c/w Adiabatic spray control system.
There are two approaches to water management in the cooling system: pumped pad and once through system. Previously, most designs used the pumped pad system, where water recirculates through a pump. However, this can lead to an increase in dissolved solids concentration if water quality is not closely monitored. As a more practical solution, the once through system directs water through the pad and straight to drain. With the pumped pad some manufacturers have even recommend using de-mineralised water, but this can be expensive. Evapco’s eco Air Series units utilise the once through pad system, which eliminates the need for expensive water treatment.
In conclusion, Evapco constructs coolers with a focus on coil construction, fan section options, control systems and incorporating efficient adiabatic coolers and condensers. Their goal is to provide reliable and energy-efficient cooling solutions for various applications that offer tested and certified capacity.
