Durham AWT Plant Transforms Nutrients into Fertilizer
Clean Water Services' Durham Advanced Wastewater Treatment Facility in Tigard, Ore., on June 10 officially opened its new facility that recovers phosphorus and other nutrients from wastewater and recycles them into environmentally safe premium-quality commercial fertilizer.
The water resource management utility, which serves more than 500,000 customers in urban Washington County west of Portland, owns and operates the technology in an innovative public/private partnership with Ostara Nutrient Recovery Technologies Inc. of Vancouver.
Developed by Ostara, the new technology increases plant capacity and reduces maintenance costs, while creating a revenue-generating byproduct.
The utility and the company will share revenue from the commercial sale of the fertilizer byproduct, which is being marketed throughout Oregon and the Pacific Northwest under the brand name Crystal Greenâ.
"We anticipate that the $2.5 million capital cost of incorporating this technology will be recovered within five years from a combination of Crystal Greenâ revenues and operational cost savings of up to $500,000 per year,” said Bill Gaffi, general manager at Clean Water Services.
Phillip Abrary, president and chief executive officer of Ostara, said Clean Water Services' Durham facility is the first in the world to implement a full-scale commercial operation, where 100 percent of the wastewater stream is being treated with the nutrient recovery technology. A municipal wastewater treatment plant in Edmonton, Alberta, has been operating with the Ostara technology for more than a year, however it is not a full-scale operation like the commercial facility in Oregon.
Abrary said treatment systems typically separate sewage sludge solids from liquids. Treated solids can be recycled as soil amendments, as the Durham facility does. Liquids are typically reprocessed back through the wastewater system, which adds costs to the system by clogging pipes with a concrete-like scale called struvite — the result of phosphorus and ammonia (nitrogen) combining with magnesium — and by consuming up to 25 percent of the system's capacity.
Clean Water Services’ Nutrient Recovery facility is projected to remove more than 90 percent of the phosphorus in the wastewater and produce 500 tons of Crystal Green® fertilizer annually.