Optimizing the agricultural value of brushite upcycled from urban wastewater: a slow-release P fertilizer and high-grade phosphate ore.

Phosphorus which is a limited resource and an essential plant nutrient is commonly applied to agricultural land to promote plant growth. NRU is commercializing a technology to recover phosphorus from municipal wastewater in the form of an agriculturally valuable mineral called brushite. This technology addresses the need to recycle phosphorus from the waste stream in order to prevent technical problems at wastewater treatment plants and water pollution. The ultimate goal of our process is to produce a high-grade source of phosphorus that has been "upcycled" (i.e., has higher value at the end of the process than at the beginning), and brought to a point where it can be used in either agriculture or industry. At present, brushite is not a recognized phosphorus fertilizer, neither in the US nor globally, although it contains 18% phosphorus. Relatively little scientific literature is currently available to make a clear assessment of its value as a phosphorus source for plants. Despite the dominance of DAP, MAP, TSP and APP fertilizers in the market, we believe that brushite is a phosphorus mineral with high potential as a fertilizer.