RecoPhos - Recovery of phosphor from sewage sludge and sludge ashes by means of the thermo-reductive RecoPhos process

This EU project (FP7) focuses on the development of a novel process for phosphor recovery from sewage sludge and sludge ashes. Phosphor is regarded as a key resource for the agricultural and food industry, but the natural phosphate resources are found in only very low remaining quantities.

Phosphor is an essential raw material in agriculture and other industrial sectors – while natural sources of phosphate are becoming short. The Reco-Phos project aims at the recovery of this valuable resource from sludge ashes by means of a new, sustainable process.

The RecoPhos process uses the innovative In-duCab reactor design by means of which the ashes from sewage sludge combustion plants is melted in an inductively heated solid bed reactor. The induction heating systems deliver alternating magnetic fields with high energy density and thereby assure that the required reaction conditions in which the melted ashes react with carbon are reached. The reactions that take place inside of the reactor for the production of high-quality phosphor are based on the same principle as the known Wöhler procedure.

The primary objective of the RecoPhos process is to produce phosphor and phosphoric acid. Meanwhile another aim of the process is also the use of biproducts from the process. For example, besides phosphor and phosphoric acid, an iron alloy and a low-pollutant silicon sludge arise in the process. The use of the iron alloy in the metals industry and the use of the silicon sludge in the concrete industry are at the centre of the studies.

It is possible with the RecoPhos plant which is being designed and built in the course of the project to also conduct test runs on an appropriate scale and receive useful results. The design of the plant permits variation of key process parameters within a defined range and thereby receive meaningful results regarding the process behaviour

The scientific coordination of the RecoPhos project is led by the Chair of the Thermo Process Technology Department and the project management is led by the Industrial Liaison Department of Montanuniversität Leoben.

Webpage: www.recophos.org

PROJECT DATA

Title: Recovery of Phosphor from Sewage Sludge and Sludge Ashes by Means of the Thermo-reductive RecoPhos Process

Instrument: FP7 Environment, Collaborative Project

Overall cost: € 4,526,875

EC funding: € 3,421,190

Project period: 36 months

Project start: 01/03/2012

Project coordinator: Montanuniversität Leoben (AT)

Project partners: