From the sewer to the farm, via startup Ostara
Agriculture — done efficiently — can begin and end at a local sewage treatment plant. Canadian startup Ostara Nutrient Recovery Technologies has just finished building a new phosphorous-harvesting plant in the United Kingdom, its first in Europe, at one of water utility Thames Water’s waste water treatment plants in Slough, Berkshire.
Why should you care about phosphorous? The element is a key ingredient in fertilizers because it helps to keep crops healthy and productive. Creating an abundant supply of phosphorous is important for increasing food production to feed the world’s growing population.
Ostara is banking on worries — and debatable theory — that phosphorous reserves in mines are depleting, causing prices for this essential fertilizer ingredient to yo-yo dramatically in recent years. Major phosphorous producing countries include the U.S., China and Morocco.
Ostara’s Hampton projectOstara’s process harvests the phosphorous and ammonia from the waste water stream, which is diverted to its equipment, and then adds magnesium to cement a strong bond with the two minerals to form tiny crystals.
The crystals stay inside a reactor that grows the crystals until they reach about 1 millimeters to 2.5 millimeters in diameter. From there, a drying process gets rid of excess water in the crystals and also turns the crystals into a pure form that no longer contains human wastes and doesn’t smell bad.
Ostara then bags the crystals and sells them to fertilizer blenders who add other materials, such as potassium or nitrogen, to create fertilizers for sale. The startup’s technology could typically recover 25 percent to 30 percent of phosphorous in the sewage. The rest remains with the human wastes that needs treatment and disposal.
While processing phosphorous from sewage isn’t a new idea, what sets Ostara’s technology apart is its ability to grow the crystals to a large size and eliminate traces of organic materials, said Phillip Abrary, CEO of the Vancouver company.
Read the full article online at: gigaom.com