title: Thermophilic sludge digestion improves energy balance and nutrient recovery potential in full-scale municipal wastewater treatment plants.
abstract: The conventional treatment of municipal wastewater by means of activated sludge is typically energy demanding. Here, the potential benefits of: (1) the optimization of mesophilic digestion; and (2) transitioning to thermophilic sludge digestion in three wastewater treatment plants (Tilburg-Noord, Land van Cuijk and Bath) in the Netherlands is evaluated, including a full-scale trial validation in Bath. In Tilburg-Noord, thermophilic sludge digestion covered the energy requirements of the plant (102%), whereas 111% of sludge operational treatment costs could be covered in Bath. Thermophilic sludge digestion also resulted in a strong increase in nutrient release. The potential for nutrient recovery was evaluated via: (1) stripping/absorption of ammonium; (2) autotrophic removal of ammonium via partial nitritation/anammox; and (3) struvite precipitation. This research shows that optimization of sludge digestion may lead to a strong increase in energy recovery, sludge treatment costs reduction, and the potential for advanced nutrient management in full-scale sewage treatment plants.
authors.affiliation: Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: De Vrieze
authors.affiliation: Colsen BV, Kreekzoom 5, 4561 GX Hulst, The Netherlands.
authors.forename: Davey
authors.initials: D
authors.lastname: Smet
authors.affiliation: Colsen BV, Kreekzoom 5, 4561 GX Hulst, The Netherlands.
authors.forename: Jacob
authors.initials: J
authors.lastname: Klok
authors.affiliation: Colsen BV, Kreekzoom 5, 4561 GX Hulst, The Netherlands.
authors.forename: Joop
authors.initials: J
authors.lastname: Colsen
authors.affiliation: Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, United States.
authors.forename: Largus T
authors.initials: LT
authors.lastname: Angenent
authors.affiliation: Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, B-9000 Gent, Belgium; Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium. Electronic address: Siegfried.Vlaeminck@uantwerpen.be.
authors.forename: Siegfried E
authors.initials: SE
authors.lastname: Vlaeminck
mesh_terms: D000693:Anaerobiosis; D052818:Autotrophic Processes; D019149:Bioreactors; D009426:Netherlands; D012722:Sewage / Q000737:chemistry*; D064091:Waste Disposal Facilities; D018505:Waste Management / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D012722:Sewage; D062065:Wastewater
keywords: Anaerobic digestion; Biogas; Energy-positive wastewater treatment; Nitrogen recovery; Phosphorus recovery; Sewage