Firm’s technology makes wastewater drinkable
Would you drink reclaimed sewage effluent? Bill Zebuhr thinks so.
As founder and chief executive officer of Nashua-based Ovation Products Corp., he has found a way to turn dirty water into ultra-pure drinking water through vaporization and distillation — and he does it cheaper, quicker and, more importantly, cleaner than water softeners or reverse osmosis filtration, he says.
The lack of sanitation and clean drinking water is a well-documented global issue. The World Health Organization estimates that nearly 3.5 billion people are without potable water or basic sanitation. Just to bring the problem under control, WHO says it will cost $11.3 billion by 2015.
Zebuhr says the Clean Water Appliance — the system developed by his company — can do the job for just under a half a cent a gallon per hour.
“Ours is a complex, multi-faceted technology on the order of an air conditioner,” says Zebuhr. “Basically, we’re creating steam, condensing it, running the water through a heat extractor and putting out clean drinking water.”
It sounds simple enough, and in theory it is. In theory. Large, commercial-grade distillers work on the same principles, but use much different, and much larger, technology. Zebuhr’s quest was to find an efficient and economical unit that could be used in the home or office or anywhere in the world.
“What we’re doing is developing a ‘PC’ distiller for home use as opposed to a ‘mainframe,’ like large companies use,” says Zebuhr.
Working more like an air conditioner than a tea kettle, the Clean Water Appliance is packed into a unit the size of a fire hydrant. Wastewater flows into the system and is boiled to a steam through a series of heat exchangers. The steam is then compressed to a slightly higher temperature and run to an extractor that cools the steam down into water and re-collects 98 percent of the heat. The result is extremely pure drinking water and a system that is as efficient as the water is safe, says Zebuhr.
“The heat recovery is what makes it feasible to do in the home,” said Zebuhr. “By reclaiming the heat from the output and using it to heat the incoming wastewater, we can clean a gallon of water for 0.4 cents, as opposed to 35 cents with currently available countertop distillers. Furthermore, these countertop units take six hours to distill one gallon of water. We are putting into production a unit that does 20 gallons in an hour.”
Zebuhr estimates the Clean Water Appliance’s operating costs for a typical family would be about 60 cents a day, or about $200 per year.
The ‘yuck factor’
Several failsafe mechanisms are built into the Clean Water Appliance to ensure the water is potable, Zebuhr says.
First, because the water is boiled, what byproducts are left from the process are inert. Second, the pressure on the “clean” side is higher than on the “dirty” side, so if there is a leak, clean water would flow into the gray water, not the other way around. Lastly, a conductivity meter can be attached to the output (contaminants raise the electrical charge of water), measuring for increases in conductivity, and can sound an alert or stop the system altogether in the event of a failure.
Not only does the process produce water pure enough for consumption, it virtually eliminates the need for a septic tank leach field, since it reclaims 90 percent or more of the water, depending on how clean the gray water was entering the system, leaving a minuscule 10 percent leftover waste concentrate – often much less. Anyone who has ever had to have a leach field remediated to the tune of thousands of dollars can immediately appreciate the savings.
Zebuhr foresees a home system processing wastewater from the septic tank. Water could be pumped from the septic system through a pre-filter, then into the unit for purification. The waste concentrate is sent back to the septic tank and clean water out through a washing machine, garden hose or even kitchen sink. Homeowners could add a second unit to distill incoming well water connected to a storage tank, similar to current hot water tanks.
“Your well water use would drop dramatically, something like two or three gallons a day versus 200. And the amount of waste discharged into the septic tank is also much less,” says Zebuhr.
He admits one of his greatest challenges in going to market is overcoming the “yuck factor.” Scientific data and conductivity meters notwithstanding, some homeowners might find it difficult to drink their own “reclaimed water.”
“That’s why we’d begin with treating outgoing water and eliminating the leach field. Other countries, however, where their drinking water is their wastewater, would find it much better than nothing.”
The efficiency and cost savings of the Clean Water Appliance has caught the eye of the U.S. Army. “They became interested in a unit for their mobile kitchens,” says Zebuhr. “Ordinarily, they would have to bring in water tanks and truck out the waste. Now they can treat the water.” He said the Army is testing the concept with an eight-gallon-per-hour unit and will probably be purchasing a newer-generation 20-gallon-per-hour unit.
Ovation has sold other late-generation prototypes to industrial facilities in the United Kingdom to reclaim water used to wash automotive parts during manufacturing.
“A wastewater company in Minnesota will be test marketing the appliance in Minnesota, Massachusetts and New Hampshire,” said Zebuhr.
The next step for the Clean Water Appliance is to further propel their position into the industrial sector, then on to medical and commercial laboratories and wastewater treatment facilities.
Zebuhr says it will be a while before you can see the unit on store shelves.
Currently, units cost about $10,000. “We are manufacturing units this year for industrial customers. We should have a better operating margin next year to bring the cost down for the homeowner,” says Zebuhr. When in full production, he estimates home units to cost under $2,000.
So does Zebuhr have a Clean Water Appliance in his home? “Not yet. All the units we have so far are sold, but I’m eagerly waiting in line.”