energies Review Co-Management of Sewage Sludge and Other Organic Wastes: A Scandinavian Case Study Clara Fernando-Foncillas 1, Maria M. Estevez 2, Hinrich Uellendahl 3 and Cristiano Varrone 1,* 1 Section for Sustainable Biotechnology, Aalborg University Copenhagen, A.C. Meyers Vænge 15, 2450 Copenhagen, Denmark;
[email protected] 2 Aquateam COWI, Karvesvingen 2, 0579 Oslo, Norway;
[email protected] 3 Faculty of Mechanical and Process Engineering and Maritime Technologies, Flensburg University of Applied Sciences, Kanzleistr. 91–93, 24943 Flensburg, Germany; hinrich.uellendahl@hs-flensburg.de * Correspondence:
[email protected] Abstract: Wastewater and sewage sludge contain organic matter that can be valorized through conversion into energy and/or green chemicals. Moreover, resource recovery from these wastes has become the new focus of wastewater management, to develop more sustainable processes in a circular economy approach. The aim of this review was to analyze current sewage sludge management systems in Scandinavia with respect to resource recovery, in combination with other organic wastes. As anaerobic digestion (AD) was found to be the common sludge treatment approach in Scandinavia, different available organic municipal and industrial wastes were identified and compared, to evaluate the potential for expanding the resource recovery by anaerobic co-digestion. Additionally, a full-scale case study of co-digestion, as strategy for optimization of the anaerobic digestion treatment, was presented for each country, together with advanced biorefinery approaches to wastewater treatment and resource recovery. Citation: Fernando-Foncillas, C.; Estevez, M.M.; Uellendahl, H.; Varrone, C. Co-Management of Keywords: waste management; wastewater; sewage sludge; organic waste; anaerobic digestion; Sewage Sludge and Other Organic co-digestion; biorefinery; resource recovery Wastes: A Scandinavian Case Study.