Bio4Energy vice programme manager Marcus Öhman will develop a new efficient method for phosphorous recovery from waste sludge, together with colleagues in Bio4Energy. Photo by courtesy of Marcus Öhman.
"We could be at the stage of industrial demonstration of the technology in five years. Then a certain amount of time would be needed for classification of the product. We know that it would be economically beneficial for some [existing] bioenergy operations which use fluid-bed technology to start co-firing dried sludge with [fuel wood]", according to Öhman, who is a professor in Energy Engineering at the Luleå University of Technology(LTU).
The research and development project, which is the fruit of collaboration between Bio4Energy researchers at LTU and Umeå University, has been several years in the making. Now it can go ahead thanks to a recently announced multiannual grant from the Swedish Research Council Formas.
Phosphorus is an essential nutrient for plant growth and thus for food production. It is extracted by mining in a handful of countries worldwide and its maximum production is expected to peak in the year 2030. After that predictions range from 50 to several hundred years before it runs out. Research is ongoing on a handful of methods for recycling the mineral from sludge, but which either perform inadequately (when it comes to removal of toxic heavy metals present in sludge or to phosphorus recovery rates) or are inhibitively expensive, to believe Öhman.