title: Technical and economic analysis of real anaerobic digester centrate by means of partial nitrification and sustainable heterotrophic denitrification.
abstract: The reliability of partial nitrification coupled with heterotrophic denitrification for the treatment of real anaerobic digester centrate produced in a wastewater treatment plant was technically and economically assessed in two sequencing batch reactors. Removal efficiencies above 90% were consistently achieved at N-ammonium loads above 1.2 g N L⁻¹ d⁻¹. Ethanol, affluent from a waste water treatment plant (biological treatment inlet) and a zero-cost liquid residue from a chemical industry containing polyethylene glycol and sorbitol were employed as carbon source for denitrification. In this last case, a total organic carbon (TOC) requirement of 4.5 g TOC g⁻¹ NO₂⁻-N was calculated. The denitrification rate was 0.26 g NO₂⁻-N g VSS⁻¹ d⁻¹ (VSS: volatile suspended solids). These results show that a carbon-rich waste can serve as a no-cost feed for denitrifying bioreactors. An in-depth economic analysis considering the main investment and operating costs of the process was developed, showing that it can suppose yearly savings above 50% with respect to the most widely used alternative of returning anaerobic digester centrate untreated to the head of the facility.
authors.affiliation: Aeris Environmental Technologies S.L. Edifici Eureka, Campus U.A.B., 08193 Bellaterra, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Bartrolí
authors.forename: C
authors.initials: C
authors.lastname: Garcia-Belinchón
authors.forename: J M
authors.initials: JM
authors.lastname: Hidalgo
authors.forename: P
authors.initials: P
authors.lastname: Rougé
authors.forename: C
authors.initials: C
authors.lastname: Fàbregas
authors.forename: M
authors.initials: M
authors.lastname: Fortuny
authors.forename: J
authors.initials: J
authors.lastname: Lafuente
authors.forename: Ó J
authors.initials: ÓJ
authors.lastname: Prado
mesh_terms: D000693:Anaerobiosis; D019149:Bioreactors; D002244:Carbon; D003198:Computer Simulation; D058440:Denitrification; D058465:Nitrification; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical
chemical_list: D014874:Water Pollutants, Chemical; D002244:Carbon