What does it look like to overburden a system?
Usually it’s one of two things. Either you’re going to form scale in the system quickly, or elevate levels of corrosion. All water is corrosive to some degree as water is the universal solvent. In a cooling tower situation where you’re recirculating water, the higher levels of ions and particulate matter can eventually scale or corrode the system if not maintained properly.
So how does EVAPCO’s Water Saver technology work? How do you pre-treat the water?
If the water quality at a location has a conductivity of 500, our technology lowers it to 250. That ultimately doubles the cycles of concentration and that’s where water savings happen. Capacitors remove dissolved ions from the water, and over time the capacitors will fill up and the Water Saver will perform a flush cycle. We switch the positively and negatively charged capacitors, and when that happens, the ions come off the capacitor and get sent to drain at a lower flow, so as not to waste water.
This might sound like a silly question, but what is a capacitor?
It’s a conductive piece of metal that isn’t particularly special until the Water Saver sends it the electrical charge. And that electrical charge attracts the ions, which is the whole point of the system.
Can you provide a real-world example of this technology in practice?
At an Indiana high school we received a water sample from them and ran it through our water model, determining its maximum cycles of concentration as 2.5. They were looking to replace their cooling towers and optimize water treatment. We helped them with their chemical treatment program and they purchased our Smart Shield and Water Saver system. These modifications improved their makeup water 50%, allowing them to double the cycles of concentration to five, ultimately saving them 1.5 million gallons of water annually.
Let’s say a new client is interested in incorporating your Water Saver technology. Where do you start? How do you approach evaluating an overall system?
There are three different components to assess – the chillers, the water treatment, and the evaporative equipment, meaning the cooling towers or evaporative condensers. Each of these areas requires an independent look. Take the water treatment, for example. We look at several areas within the water treatment, including how they’re treating the water, how much that costs, and the quality of the water.
How do you approach evaluating the water treatment system and assessing water quality?
The first step is understanding the quality of the makeup water. Most of the time a water treater will have an idea of the local water quality, but it’s still important to evaluate.
Second, is taking a close look at the evaporative equipment system. When we’re out in the field, we inspect things like what type of piping is in use, ensuring there are no dead legs, and ultimately identifying what the water is contacting. It’s critical this assessment is conducted in person. There are no one-size-fits-all solutions in water treatment.
Third, is identifying the type of evaporative cooling equipment. Is it a cooling tower, an evaporative condenser, or is it a closed-circuit cooler? The type of equipment in use impacts the overall water treatment.
The fourth step is assessing the types of materials used in construction. Whatever the water will touch is important – whether it’s the tower, piping, heat exchangers involved, the chiller, or anything else. The materials of construction of everything in the system influence the overall water treatment.
It’s interesting that in steps two through four, you’re not looking at the water itself.
Correct, the most important part of the evaluation is what the water is contacting. We, of course, pull a sample of the makeup water and recirculating water, but we don’t even look at that until later. What we’re most interested in is everything that’s physically part of the system.
Are there any other steps?
The next step is evaluating the temperatures. Higher temperatures mean that scale and corrosion both happen faster. Traditional HVAC temperatures are 95 oF into the tower and 85 oF out, but industrial sites are typically higher. I have even visited sites with temperatures close to water’s boiling point. Identifying the temperature matters, whether it’s high or low, as it strongly influences the treatment plan I propose.
After you assess the system, how do you analyze the makeup and recirculating water?
We have our own in-house laboratory. This helps us not only for the original evaluation at a new site, but also existing customers. Analyzing the makeup and recirculating water helps inform our decision- making when installing or retrofitting a current system, as the composition of the water can help us decide, for example, whether to use galvanized or stainless steel.