Measurement of Biosolids Compost Odor Emissions from a Windrow, Static Pile, and Biofilter

摘要

A pilot study was conducted to compare odor emissions from a windrow process and an aerated static pile and to determine the odor reduction efficiency of a pilot two-phase biofilter for odor control of biosolids composting. Chemical compounds identified as responsible for odors from biosolids composting include ammonia, dimethyl disuifide, carbon disulfide, formic acid, acetic acid, and sulfur dioxide (or carbonyl sulfide). Aeration was found to reduce the concentration of ammonia, formic acid, and acetic acid by 72, 57, and 11 percent, respectively, compared with a nearby windrow, while dimethyl sulfide, carbon disulfide, and sulfur dioxide (or carbonyl sulfide) concentrations were below detection limits. Using dilulion-to-threshold olfactometry, aeration followed by biofiltration was found to reduce the odor from biosolids composting by 98 percent. Biofiltration also altered the character of odor emissions from biosolids composting, producing a less offensive odor with an earthy character. Biofiltration was found to reduce the concentration of ammonia, dimethyl disulfide, carbon disulfide, formic acid, acetic acid, and sulfur dioxide (or carbonyl sulfide) by 99, 90, 32, 100, 34, and 100 percent, respectively. The concentrations of those odorants were estimated to be 3700. 110 000,26,37,5, and 1.2 times reported human detectionlimits before the two-phase biofilter, respectively, and 42,9600,18,0,3, and 0 times human detection limits after the biofilter, respectively. Water Environ. Res., 76, 310 (2004).