If it’s unfair to judge a book by its cover, it’s equally unfair to judge a promising new technology by the ho-hum building housing it. When first arriving at Xogen Technologies’ wastewater treatment pilot plant, contained within what’s best described as a big white metal cube, one could be excused for wondering, “I drove 90 minutes from Toronto to Orangeville to see this?” 

Walk inside, however, and the geek in the journalist perks up. The pilot plant, located on the grounds of Orangeville’s existing water pollution control facility, contains a unique integration of holding tanks, pipes and electrode assemblies that handle the odour-free treatment of up to 30 litres of raw wastewater per minute. Not a huge amount, but this pilot plant has demonstrated since 2010 the important role that electro-oxidation can play in the future of water treatment — from the killing of pathogens and breaking down of pharmaceutical compounds in municipal sewage to the destruction of cyanide and ammonium in gold mine tailings.

Non-descript on the outside, the interior of Xogen Technologies’ pilot wastewater treatment plant in Orangeville, Ont. is proving that electro-oxidation can be a more effective and low-cost method of removing contaminants from water. Operating since 2011, the plant is also being adapted for industries like mining. Photo credit: Xogen Technologies 

If the company can get it right, the commercial opportunity is potentially huge. BCC Research, a market research firm in Wellesley, Mass., projects that the global market for wastewater treatment — from delivery equipment and instrumentation to process equipment and treatment chemicals — will surpass US $93 billion in 2016, up from $57 billion in 2011. Xogen cites other studies pointing to a global market that could reach $115 billion over the next two to three years, driven by rising per capita water consumption and more stringent regulations requiring industry to recycle the water it uses and remove contaminants not easily captured by existing treatment technologies.

Pharmaceutical compounds and hormones that pass through the human body and are flushed down the toilet are one example of where Xogen may have an edge. “For the most part, existing wastewater treatment plants don’t remove them, so they end up being discharged into our rivers and lakes,” says Xogen CEO Angella Hughes. “In the United States, for example, they have drinking water supplies that now contain pharmaceuticals. That’s not yet regulated, but it will be coming soon.” 

At the heart of Xogen’s approach is a patented electrolytic process originally designed to turn tap water into two parts hydrogen, one part oxygen gas. During the late 1990s, its predecessor company Xogen Power of Calgary had plans to use the novel electrolysis technology as part of a hydrogen-fuelled home furnace. This was at a time when hydrogen was a buzzword for investors and enthusiasm for a coming hydrogen economy had driven up the shares of fuel cell companies like Ballard Power — an example of how hype can bring multibillion-dollar valuations to profitless ventures. 

Xogen Technologies CEO Angella Hughes. Photo credit: Xogen Technologies 

“As you have no doubt noticed, the predicted hydrogen economy has still not arrived,” says Hughes, who was hired by Xogen Power in 2000 to manage production of its planned hydrogen-burning furnace. A year after Hughes’ arrival, the company was approached with the idea of using its electrolytic process to break down contaminants in wastewater. To its delight, testing of the process worked well and fast. By stimulating oxidation of contaminants, organic nasties were removed in minutes — versus the hours it takes with most conventional, often chemical-intensive treatment methods. 

Hughes, who before joining Xogen Power had spent 13 years supporting aerospace manufacturing efforts at The Boeing Company, says the tests on wastewater encouraged the company to rethink its strategy. Splitting water for its hydrogen was, upon reflection, not the lowest hanging fruit. “In order to realize shareholder value, it was felt that there was much more potential in the development of the technology for wastewater treatment,” says Hughes. She’s now applying her experience working with manufacturers and suppliers while at Boeing to Xogen’s new pursuit. It helps that she supported fabrication of the Space Shuttle’s main engine and worked on the International Space Station. “Some of what I learned at Boeing are things I learned not to do.”

In 2004, publicly traded Xogen Power was restructured to become a private company called Xogen Technologies, now under the leadership of Hughes. The head office was moved from Calgary to Orangeville, where testing on raw sewage eventually led to construction of the company’s first pilot plant with funding assistance from Sustainable Development Technology Canada. The building — that white metal cube — sits on 149 square metres of land, and while simple from the outside it hides a complex operation that has stripped out many of the inefficiencies associated with conventional wastewater treatment processes.

Here’s how it works: Raw, pre-screened sewage entering the plant is pumped into reactor modules that contain a series of electrolytic cells. When an electric charge is applied to the cells the water decomposition that results creates hydrogen and oxygen gases, the latter functioning to kill oxygen-hating bacteria in the wastewater. The electrodes also oxidize contaminants in the wastewater directly to generate the powerful ‘secondary’ oxidants ozone, hydrogen peroxide and hydroxyl radicals. These go on to further break down organic matter into hydrogen, oxygen, carbon dioxide and nitrogen. Oxidation can also result in the formation of chlorine. “It ends up being like an on-demand chlorination and oxidation system,” says Craig Gagnon, a technical consultant working with Xogen to develop a commercial roadmap for its technology. “The system is not extremely selective, so it actually operates to provide combined treatment, rather than be particular in what it targets,” Gagnon says. 

Gagnon adds that the hydrogen and oxygen bubbles created by the charged electrodes serve another function called electrofloatation. In essence, as the bubbles rise to the surface of the reactor they carry suspended solids to the top, allowing for easy removal. At the same time, the electric charge in the water causes oils, metals and heavier solids to coagulate and sink to the bottom. The overall result is the speedy removal of more than 99 per cent of some of the most common sewage contaminants.

In addition to being a virtually odourless process and working much faster than conventional chemical and biological treatment systems, Xogen touts the fact its approach eliminates the need to purchase and store hazardous treatment chemicals or microorganisms. Likewise, no ultraviolet disinfection or a separate system to handle sludge floatation is required.

A plant’s physical footprint can also be up to 75 per cent smaller than conventional treatment plants and operational costs are expected to be significantly lower, says Hughes, explaining that research continues on ways to find the most cost-effective way to power the process and lower product costs. On that last point, the company has been working since 2007 with a student research group at the University of Toronto, supported in part by NSERC and the Ontario Centres of Excellence. “How much does the electrochemical cell cost and how much does the power supply cost? Those are the two big issues,” says Francis Dawson, a professor of energy systems at U of T’s Department of Electrical and Computer Engineering. Dawson and his team are focused on finding the most efficient power supply configuration for Xogen’s system. His colleague in the Department of Materials Science and Engineering, Harry Ruda, is at the same time leading a search for electrode materials that are inexpensive, easy to manufacture and resist corrosion when continually exposed to a flush of raw sewage. “That is a tough challenge. There aren’t too many materials that can satisfy all those constraints,” says Dawson. “Every wastewater stream is different. You may have to tailor the electrode materials you use to what it is you want to treat.”

All of this university-led research is necessary if Xogen is to one day have a broad impact on the wastewater treatment marketplace, but it doesn’t pay the bills that are coming in today. Cognizant of the need to constantly improve its system, Xogen, like most startups, also needs to find the quickest path to commercialization if it hopes to survive financially. For this reason, Xogen has shifted its attention away from municipal wastewater treatment to industrial treatment. “The sales cycle for municipal plants is very long,” says Hughes, explaining that third party due diligence and the required environmental assessments can take years, particularly when new technologies without track records are being considered. 

Xogen Technologies is at the forefront of electro-oxidation­ for wastewater treatment. While the electrolysis technology was originally­ designed to generate­ hydrogen from water­ for energy applications­, it works just as well to destroy pathogens­ or complex chemical contaminants in the wastewater. Photo credit: Xogen Technologies 

On the other hand, private industry can move much faster, which is why the company installed two new demonstration plants last year, one at a leading industrial environmental firm and the other at a large company’s packaging plant. The intent of the latter project, according to Xogen, is to validate the technology with an aim to commercializing the system for use at packaging facilities around the world. At the same time, bench-scale testing of the process is being done for a major Canadian waste management company. “Successful bench testing is expected to lead to the purchase of a number of Xogen systems for their wastewater treatment facilities,” the company states.

While some projects can move faster by working with private industry, Gagnon says there are no short cuts. “Water treatment is not simple. Treating 100 million litres of water is difficult. There are thousands of variables that can affect a technology and the only way to acquire knowledge about them is through experience.” 

One emerging bright spot is the mining sector, particularly gold companies. Extracting gold from rock typically involves the use of an acid leach process, which results in tailings with harmful concentrations of cyanide and/or ammonia. One of the world’s largest gold mining markets, Australia, is facing severe water scarcity. This is putting pressure on gold miners to reuse water or do a better job of cleaning up the water they discharge.

In Canada, regulations are being tightened for wastewater containing cyanide and ammonium. Both can be destroyed through Xogen’s process, either through direct oxidation or secondary oxidants like peroxide. This is why the company is currently doing bench scale testing for a Fortune 500 gold mining company. “We’re being assessed to see if we meet this new criteria and in our first test we do,” says Hughes. “We’re in the second phase now, which is also looking good.” The company hopes this will lead to construction of a demonstration plant in Ontario followed by a full-scale commercial plant. Hughes is optimistic. “They have money to solve their problems and they have tremendous regulatory pressures.” 

Gagnon agrees that mining is where the focus must be. And while electro-oxidation for use in wastewater treatment isn’t new, Xogen believes that the materials used in its electrodes, the efficient way in which its system has been integrated and its determination to adapt its process to customer needs will carry it through the gruelling journey to commercialization. And don’t forget the hydrogen that results from the process, or the fact that the system is driven by electricity. Gagnon says that the cost of the system could be offset by burning the hydrogen for energy. Will it even be possible, in the future, to utilize solar and wind for power? “Absolutely,” Gagnon says.