title: Pilot-plant study of wastewater sludge decontamination using a ferrous sulfate bioleaching process.
abstract: The objective of this research was to investigate the performance of the ferrous sulfate bioleaching (FSBL) process in a pilot plant for decontamination and stabilization of wastewater sludge. Batch and continuous experiments, conducted with two 4-m3 bioreactors using indigenous iron-oxidizing bacteria (20% v/v of inoculum) with addition of 4.0 g ferrous sulfate heptahydrate per liter of sludge initially acidified to pH 4.0, were sufficient for effective heavy metal (cadmium, copper, manganese, zinc, and lead) removal yields. The average metal removal yields during the FSBL process were as follows: cadmium (69 to 75%), copper (68 to 70%), manganese (72 to 73%), zinc (65 to 66%), and lead (16%). The FSBL process was also found to be effective in removing both fecal and total coliforms (abatement > 5 to 6 log units). The nutrients content (nitrogen, phosphorus, and magnesium) were also preserved in decontaminated sludge.
authors.affiliation: Institut national de la recherche scientifique (Centre Eau, Terre et Environnement, Université du Québec, Canada.
authors.forename: Guy
authors.initials: G
authors.lastname: Mercier
authors.forename: Patrick
authors.initials: P
authors.lastname: Drogui
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Blais
authors.forename: Myriam
authors.initials: M
authors.lastname: Chartier
mesh_terms: D042763:Acidithiobacillus / Q000378:metabolism*; D001673:Biodegradation, Environmental; D011232:Chemical Precipitation; D003666:Decontamination / Q000379:methods*; D003890:Desiccation; D005296:Ferrous Compounds / Q000378:metabolism*; D005308:Fertilizers / Q000032:analysis; D019216:Metals, Heavy / Q000302:isolation & purification; D050296:Microbial Viability; D010084:Oxidation-Reduction; D010865:Pilot Projects; D012037:Refuse Disposal / Q000379:methods; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000378:metabolism
chemical_list: D005296:Ferrous Compounds; D005308:Fertilizers; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; C020748:ferrous sulfate