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Nutrient Recovery Co. Prevents Phosphorus From Entering Waterways, Recycles it as Fertilizer

April 2, 2012 |

Phosphorus is an important building block for all living things—but too much of the mineral can be harmful when it reaches waterways and becomes a pollutant.

Phosphorus is also one of the three core nutrients along with Nitrogen and Potassium required for plant growth. It is also irreplaceable. As the US Geological Survey notes in its 2011 Mineral Commodity Summary on Phosphorus: “There are no substitutes for phosphorus in agriculture.”

Through its Pearl® Process Technology, Vancouver, British Columbia-based Ostara Nutrient Recovery Technologies, Inc. has come up with a solution to both recycle phosphorus and prevent it from polluting waterways. The Pearl® Process (designed by University of British Columbia engineers) not only removes phosphorus and other nutrients from wastewater sludge, but it also turns the elements into a fertilizer that the company sells to growers under the name Crystal Green. In the end, the process results in the utilization of recycled phosphorus as opposed to phosphorus that must be mined from the ground.

“There’s a lot of need for these types of solutions,” said F. Phillip Abrary, President, CEO and co-founder of Ostara. “There’s some certain regions in the U.S. that are extremely nutrient sensitive like the Chesapeake Bay, for example, or the Gulf of Mexico.”

The nutrient recovery technology that Ostara uses in its Pearl® Process was first developed at the University of British Columbia by a group of engineers, who then made it available for licensing. Dr. Don Mavinic, Professor of Civil Engineering at the university and one of the four inventors of the technology, said he had turned down multiple licensee applicants before coming across the right choice. He selected Abrary and his two business partners, Joseph McHugh and Ted Jones.

Ostara, founded in 2005, now has four commercial nutrient recovery facilities in the U.S. and Canada. The company also plans on adding three new facilities, including one in Europe, Abrary said. Municipal entities are the main customers on this end of the business.

Here’s the issue: Many wastewater treatment plants have large quantities of nitrogen and phosphorus in their sludge dewatering streams, according to the company’s website. These nutrients lead to the formation of struvite, a concrete-like mineral deposit that can clog pipes, pumps and valves. Besides causing an environmental hazard, the struvite buildup can negatively impact the plant’s efficiency and add to its operating and maintenance costs, according to Ostara.

Ostara's Nutrient Recovery Facility at the City of York's Wastewater Treatment Plant in York, PA. Photo courtesy of Ostara Nutrient Recovery Technologies.

Here’s how Ostara’s solution works: Municipal bodies agree to purchase Ostara’s nutrient recovery technology or to use it on a fee-based model, Abrary said. Ostara’s website describes what the technology does: “The technology is based on controlled chemical precipitation in a fluidized bed reactor that recovers struvite in the form of highly pure crystalline pellets or ‘prills.’ Nutrient-rich feed streams are mixed with magnesium chloride and, if necessary, sodium hydroxide and then fed into the Pearl reactor where minute particles or struvite ‘seeds’ begin to form. Like a pearl, these seeds grow in diameter until they reach the desired size – 1.0 mm to 3.5 mm – which is precisely controlled by varying key parameters.”

The end result is the company’s fertilizer product, Crystal Green. Ostara cites that the process can also result in up to 90 percent of phosphorus and 40 percent of ammonia load removal from sludge dewatering liquid in a municipal wastewater treatment plant.

Mavinic said phosphorus can cause eutrophication (the increase of dissolved nutrients in bodies of waters, which stimulates the growth of aquatic plant life, resulting in the depletion of dissolved oxygen). That leads to problems such as algae blooms in waterways.

“When you put a piece of phosphorus in, it stays there forever,” Mavinic said. “So you have a lot places in the world that have too much nutrient loading.”

Ostara got its start at a demonstration facility in Edmonton, Canada. Its commercial facilities operating today include Hampton Roads Sanitation District’s Wastewater Treatment Plant (WWTP) in Suffolk, Va.; the City of York’s WWTP in York, Pa.; Clean Water Services’ Advanced Waste Water Treatment Plant (WWTP) in Portland, Ore.; and another Clean Water Services WWTP in Rock Creek, Ore. that is still in launch mode. Three new facilities will be located in the City of Saskatoon in Canada; in London, UK; and in Madison, Wisc. The Saskatoon and London facilities are expected to be fully operating late this summer, while the Madison facility won’t be fully operating until the spring or 2014, Abrary said.

Transforming Recycled Phosphorus into Fertilizer

Ostara’s Crystal Green product is a “slow-release” phosphorus fertilizer, meaning it takes longer for the phosphorus to be released to the plant, which is more beneficial to both the plant and the environment, Abrary said. The fertilizer is made up of phosphorus, nitrogen and magnesium.

“Most phosphorus fertilizers, the vast majority of what’s available in the market today, are highly soluble compounds,” he said. “You put them in, you water them, and they dissolve rather quickly, so the normal plant has less than 30 days to take up those nutrients—the phosphorus—and normally it can’t. It can only take up so much.”

When that happens, Abrary said it’s more likely that the remaining material will either get washed away or trapped in the soil without another element to react with, which makes it much less available to the plant.

“Having a slow release material that kind of releases very slowly over time allows you to be a lot more nutrient efficient,” he added. “You can put the same pounds of nutrients down and essentially feed three or four times as many plants with it.”

Crystal Green is then sold to a number of large fertilizer blend product distributors, who sell directly to growers. In these fertilizer blends, Crystal Green is combined with other nutrients to create finished products for specific markets, Abrary said.

“Primarily right now, we’re targeting turf and horticulture-nursery type operations,” Abrary said.

Ostara is still in the single thousands of tons of production for Crystal Green today, which Abrary said is a very small representation of the overall market. He estimates that about 5 million tons of phosphorus a year is consumed in North America. Abrary noted that phosphorus obtained through Ostara’s Pearl process is much more environmentally sustainable than using phosphorus obtained through mining, a process in which the supply cannot be replenished.

Business Model

The combination the nutrient removal process and the Crystal Green production make for a solid business plan, according to Abrary. Municipalities are able to afford the Pearl technology because of the fact that they are able to produce the Crystal Green fertilizer and sell it to Ostara, he said. The income from the fertilizer offsets operational costs, and municipalities that purchase the technology usually have a payback period of about five years, Abrary said.

Nate Cullen, engineering division manager for water resources management utility Clean Water Services in Oregon, said the process has been a success for its Portland, Ore. advanced wastewater treatment plant, one of Ostara’s facilities. Using the Ostara Pearl system has allowed the plant to slash its chemical use by 40 percent and its production of bio-solids by 20 percent, Cullen said.

“It helped stabilize our process, making us be able to run the treatment plant more cost-effectively and more reliably to be able to meet our permit,” he said. “We’re cleaning up the wastewater and putting it back into the watershed, and we’ve put it in cleaner than the river is, so we’re actually improving the quality of the Tualatin River that we discharge into.”

Abrary said the main challenge Ostara has is dealing with municipal customers. That’s because they are usually extremely conservative and decision making can be a lengthy process, he said. However, he notes that the benefit is that they generally become long-term customers.

Another challenge for the company was making sure it could become large enough to penetrate the fertilizer market. Abrary said bringing the technology to a commercial level required a scale-up by a factor of 100. Ostara is backed by venture capital companies VantagePoint Capital Partners in the U.S. and Frog Capital in the UK, as well as by individual investors.

There are plans for Ostara to expand its nutrient recovery side of the business into the industrial sector. As for geographic expansion, Abrary said the company is in contact with literally hundreds of cities, and there are tens of cities with which it is having advanced discussions. The goal is to continue growing in North America, then to further expand into Europe over the next couple of years, and to later on explore options in Asian markets.

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