Mary Ann Bruns, Jerzy Dec, Ephraim Govere, Pat Topper, and Eileen Wheeler
The Pennsylvania State University
Animal waste odors arising from products of anaerobic microbes create community relations problems in agriculture. Ferric chloride, a common flocculating agent used in wastewater treatment, provided the best source of bioavailable Fe(III) to promote anaerobic respiration by bacteria for more complete oxidation of odorous compounds to CO2. Fe(III) from FeCl3 but not from pre-synthesized ferrihydrite (FeOOH) or magnetite, was available for reduction by iron-respiring bacteria, and odor reduction was enhanced in the presence of limestone gravel. After six days, higher Fe(II) concentrations were accompanied by significant decreases in volatile fatty acids and phenols.