title: Enhancing recovery of ammonia from swine manure anaerobic digester effluent using gas-permeable membrane technology.
abstract: Gas-permeable membrane technology is useful to recover ammonia from manure. In this study, the technology was enhanced using aeration instead of alkali chemicals to increase pH and the ammonium (NH4(+)) recovery rate. Digested effluents from covered anaerobic swine lagoons containing 1465-2097 mg NH4(+)-N L(-1) were treated using submerged membranes (0.13 cm(2) cm(-3)), low-rate aeration (120 mL air L-manure(-1) min(-1)) and nitrification inhibitor (22 mg L(-1)) to prevent nitrification. The experiment included a control without aeration. The pH of the manure with aeration rose from 8.6 to 9.2 while the manure without aeration decreased from 8.6 to 8.1. With aeration, 97-99% of the NH4(+) was removed in about 5 days of operation with 96-98% recovery efficiency. In contrast, without aeration it took 25 days to treat the NH4(+). Therefore, the recovery of NH4(+) was five times faster with the low-rate aeration treatment. This enhancement could reduce costs by 70%.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Coastal Plains Soil, Water and Plant Research Center, 2611 W. Lucas St, Florence, SC 29501, USA. Electronic address: Patrick.dube@ars.usda.gov.
authors.forename: P J
authors.initials: PJ
authors.lastname: Dube
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Coastal Plains Soil, Water and Plant Research Center, 2611 W. Lucas St, Florence, SC 29501, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Vanotti
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Coastal Plains Soil, Water and Plant Research Center, 2611 W. Lucas St, Florence, SC 29501, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Szogi
authors.affiliation: Agriculture Technological Institute of Castilla and Leon (ITACyL), Valladolid, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: García-González
mesh_terms: D000641:Ammonia / Q000032:analysis; D064751:Ammonium Compounds / Q000032:analysis*; D000693:Anaerobiosis; D000822:Animal Husbandry; D000818:Animals; D019149:Bioreactors; D006863:Hydrogen-Ion Concentration; D008372:Manure / Q000032:analysis; D008567:Membranes, Artificial; D058465:Nitrification; D009657:North Carolina; D013552:Swine; D018505:Waste Management / Q000295:instrumentation / Q000379:methods*
chemical_list: D064751:Ammonium Compounds; D008372:Manure; D008567:Membranes, Artificial; D000641:Ammonia
keywords: Ammonia recovery; Anaerobic digestion; Gas-permeable membranes; Nutrient recovery; Swine manure; Waste management