Sustainable and efficient recycling of phosphorus from sewage sludge through FBC

Published: 21 January 2019

• Recent research has shown that during fluidized bed combustion of sewage sludge it is possible to produce large bed ash particles, ash granules, with high contents of plant-available P.
• The technology has not yet been demonstrated on an industrial scale, but a consortium consisting of Sandviken Energi, Andritz, LTU and UmU has performed a feasibility study where technical detail solutions for the production of 100% sludge granules were studied in pilot scale and how a reconstruction of a 20 MW plant could be carried out.
• The results from the previous study show that it is possible to produce sufficiently durable sludge granules, but the strength of the combusted sludge granules (the ash granules) is critical for enabling efficient recovery of the sludge P content.
• The purpose of this project is, therefore, to evaluate opportunities for the production of hard ash granules through co-pelletization of sewage sludge with different biomass/fuel additives
• Funding: Swedish Water Association + LTU (0.9 MSEK in total)
• Partners: Andritz, LTU, UmU , Sandviken Energi AB
• Duration: 2018-2019
• Contact persons: Marcus Öhman (LTU), Gustav Häggström (LTU)