title: Hydrolytic anaerobic reactor and aerated constructed wetland systems for municipal wastewater treatment - HIGHWET project.
abstract: The HIGHWET project combines the hydrolytic up-flow sludge bed (HUSB) anaerobic digester and constructed wetlands (CWs) with forced aeration for decreasing the footprint and improving effluent quality. The HIGHWET plant in A Coruña (NW of Spain) treating municipal wastewater consists of a HUSB and four parallel subsurface horizontal flow (HF) CWs. HF1, HF2 and HF3 units are fitted with forced aeration, while the control HF4 is not aerated. All the HF units are provided with effluent recirculation, but different heights of gravel bed (0.8 m in HF1 and HF2, and 0.5 m in HF3 and HF4) are implemented. Besides, a tobermorite-enriched material was added in the HF2 unit in order to improve phosphorus removal. The HUSB 76-89% of total suspended solids (TSS) and about 40% of chemical oxygen demand (COD) and biological oxygen demand (BOD). Aerated HF units reached above 96% of TSS, COD and BOD at a surface loading rate of 29-47 g BOD5/m2·d. An aeration regime ranging from 5 h on/3 h off to 3 h on/5 h off was found to be adequate to optimize nitrogen removal, which ranged from 53% to 81%. Average removal rates of 3.4 ± 0.4 g total nitrogen (TN)/m2·d and 12.8 ± 3.7 g TN/m3·d were found in the aerated units, being 5.5 and 4.1 times higher than those of the non-aerated system. The tobermorite-enriched HF2 unit showed a distinct higher phosphate (60-67%) and total phosphorus (54%) removal.
authors.affiliation: a Department of Physical Chemistry and Chemical Engineering I , University of A Coruña , A Coruña , Galiza , Spain.|b AIMEN , Porriño - Pontevedra , Spain.
authors.forename: A
authors.initials: A
authors.lastname: Pascual
authors.affiliation: c Sedaqua (Spin-off from University of A Coruña) , O Porriño, Pontevedra , Spain.
authors.forename: D
authors.initials: D
authors.lastname: de la Varga
authors.affiliation: d Department of Bioscience , Aarhus University , Aarhus , Denmark.
authors.forename: C A
authors.initials: CA
authors.lastname: Arias
authors.affiliation: e Rietland bvba , Minderhout , Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Van Oirschot
authors.affiliation: f Kilian Water , Bryrup , Denmark.
authors.forename: R
authors.initials: R
authors.lastname: Kilian
authors.affiliation: b AIMEN , Porriño - Pontevedra , Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Álvarez
authors.affiliation: a Department of Physical Chemistry and Chemical Engineering I , University of A Coruña , A Coruña , Galiza , Spain.
authors.forename: M
authors.initials: M
authors.lastname: Soto
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis; D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D006868:Hydrolysis; D009566:Nitrates / Q000032:analysis; D009573:Nitrites / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D010710:Phosphates / Q000032:analysis / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis / Q000737:chemistry; D006109:Poaceae; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000032:analysis / Q000737:chemistry; D014873:Water Pollutants / Q000032:analysis / Q000737:chemistry; D053833:Wetlands
chemical_list: D064751:Ammonium Compounds; D009566:Nitrates; D009573:Nitrites; D009584:Nitrogen; D010710:Phosphates; D010758:Phosphorus; D062065:Wastewater; D014873:Water Pollutants
keywords: HUSB anaerobic digester; aerated constructed wetlands; municipal wastewater; nitrogen removal; phosphorus removal