An Ontario company has created an ozone-based system for treating and recycling fertilized irrigation runoff water used in greenhouses.
The Fertigation Treatment System, created by Leamington-based Climate Control Systems Inc., is the result of extensive research on the differences between ozone and ultraviolet water treatments, said Eric Labbate, owner and president.
“We did quite a bit of research last year, and what we found is UV works, provided that all of the conditions in the water are ideal,” he said.
The problem is, conditions in a working vegetable greenhouse aren’t always ideal, Labbate said.
If water is 65% to 70% pure, UV rays can sterilize used water, he said.
However, what typically happens with fertilized water in a vegetable greenhouse is blue and green algae grows in it.
What makes algae particularly difficult to get rid of is that it’s invisible to the naked eye, Labbate said.
Though you can’t see it, that algae reduces the purity of the water from the 65% to 70% that UV requires to work properly to more like 30%, Labbate said.
“And at 30%, it’s definitely not doing its job,” he said.
In addition to the problem with algae, growers also have trouble properly filtering, via UV technology, some of the substrates they use for growing, Labbate said.
As a result, many have to dump that water when it becomes unusable — something that Canada’s environmental ministry frowns on, and that can result in a fine.
In contrast with UV rays, ozone kills all bacteria in used water, regardless of algae or substrate content, Labbate said.
“When we compared them, we found ozone was a much surer thing,” he said. “We’re convinced it’s the way to go.”
Not only is ozone better than UV, it’s also more effective than heat treatments, Labbate said.
Not to mention cheaper and more environmentally-friendly, he said.
“With heat, you have to burn fuel,” Labbate said. “It’s an ongoing cost.”
By contrast, once the initial investment is made in Climate Control Systems’s ozone treatment system, “you’re set for five to eight years,” he said.
Ozone also has the maintenance advantage on UV, since UV lamps have to be replaced typically every year, Labbate said.
Climate Control Systems’s patented Plasma Ozone Sterilization technology, as it is called, uses 94% pure oxygen, the same high grade hospitals use, he said.
That gives users the luxury of producing a lot more ozone with a smaller unit, Labbate said.
“It’s low-cost, totally automatic and has low maintenance,” he said.
The system will cut growers’ irrigation water costs by up to 30% and fertilizer costs by as much as 40%, Labbate said.