GigaOm has an article on a startup that has built a plant to retrieve phosphorous from sewage and wastewater and turn it into fertiliser - 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 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.