The first expected outcome of the PHOSTER project will be the first-of-a-kind definition of a manufacturing route from waste streams (SSA, mining by-products), providing high-value secondary resources to fertiliser industry that could replace conventional primary critical raw materials (phosphate rocks, magnesium salts), resulting in substantial environmental and social benefits.
Considering the implementation of an effective phosphorus recovery system from SSA allowing phosphorus dissolution by wet chemical extraction of 89- 90% and subsequent precipitation of 95-96%, the expected total phosphorus recovery from SSA should be around 76-90%.
The replacement of about 15% of phosphorus from phosphate rocks for fertilisers production could be expected from the processing of more than 13 million tons of sewage sludge produced yearly in Europe in case of complete mono-incineration and resource recovery from SSA.
PHOSTER project is expected to provide recovered products with good environmental, social and economic sustainability. It will promote the social acceptance of recovered products by quantifying the positive impact of treating a locally-produced unavoidable residual waste and of closing the material loop by a safe solution, returning the favor to local economy and environment.
Regarding the mining industry, the mining waste itself from the extraction process is used for the restoration of the extraction holes, so it does not involve significant costs, with respect to the handling of the mineral for processing.
However, many tonnes of by-products of the mining process are obtained yearly in pre-treatment and enrichment processes of mining, as well as in the calcining process of magnesite to MgO. Concretely for MgO by-products, only Magna produces at least 20,000 tons/year of mining by-products, being generated as dust from the cyclones and furnaces of processing plants. In the past, these by-products were sold directly as fertilizers, but such recycling path is no longer possible. The disposal of these by-products requires a solution, highlighting the promising opportunity represented by an innovative circular solution.
To conclude, PHOSTER project aims at the simultaneous promotion of other technological solutions for the circular economy, both related to the recovery of phosphorus and other resources. It will promote the creation of a circular supply chain, including all relevant stakeholders (waste producers and managers, mining industry, fertiliser industry, technology developers, policy makers).