Crystal Green, and Sparkling Clean?

The Inspiring Innisfil 2020 strategic plan calls for greater protection of Lake Simcoe, improved water quality and more local employment opportunities. With that in mind, a new Canadian environmental technology recently caught my attention.

In May, Tyler Hamilton wrote about a Vancouver-based company, Ostara Nutrient Recovery Technologies, that found a way to “economically extract phosphorus, ammonia and magnesium from the sludgy liquids in municipal waste water. It then turns these nutrients into a pure, slow-release compound that can be used as and blended with commercial fertilizer products. It calls the pelletized compound Crystal Green.”

This is important because phosphorous is an essential plant nutrient that encourages rooting, blooming and fruit production.

[Phosphorus] “was a limiting nutrient in most ecosystems prior to human settlement and agricultural development. Moreover, because [nitrogen] and [phosphorus] were in high demand, these nutrients were stored and recycled in close proximity to the locale from which they were scavenged. This pattern was true for plants and animals, including humans because, prior to urbanization, feces from livestock and humans along with other composted waste was returned to the soil, thereby closing nutrient recycling loops and maintaining the fertility of the soil.” (source: Environment Canada)

With urbanization and mechanized agriculture, phosphorus becomes depleted from the soil over time and gets replaced through the use of commercial fertilizer (phosphorous content is the middle number displayed on a bag of fertilizer).  The strange paradox is that while mined phosphorus is reportedly reaching depletion (158 million tonnes of phosphate-bearing rock is mined annually), urban sewage is a primary source of phosphorous contamination of bodies of water.

According to Environment Canada, “nutrients in the form of foodstuffs flow from the farm to the cities, where most ultimately end up in landfill (sewage sludge, incinerator ash), or in surface or ground watersHousehold sewage is the largest point source of N [nitrogen] and P [phosphorous] to the Canadian environment and will likely continue to be so. In 1996, an estimated 5.6 thousand tonnes of total P …  were released to lakes, rivers and coastal waters from municipal wastewater treatment plants in Canada… This load occurred despite the fact that, in 1996, 73% of Canadians were served by municipal sewer systems and at least 94% of the wastewater collected by sewers received primary or higher treatment.”  (online: Threats to Sources of Drinking Water and Aquatic Ecosystem Health in Canada – Environment Canada)

A technology that claims to economically capture up to 85 per cent of phosphorus from municipal waste is attracting attention.  Ostara has four commercial demonstration plants, including its first systems in Edmonton. The company now has its eye on the European market and “There are a couple of fairly significant Canadian cities in the design phase right now.”

See: The case for recycling the stuff in your toilet, Tyler Hamilton, May 2011

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