Removal of odor emitted from composting facilities using a porous ceramic biofilter Available to Purchase

A field experiment was conducted using a full-scale ceramic biofilter (approximately 150 m³/min) in order to determine the potential for biofiltration to remove malodorous gases from composting facilities. The main compounds found in malodorous gases were NH₃ and H₂S. These compounds were analyzed by a UV-spectrophotometer and gas chromatograph. The microbial carrier was a porous ceramic consisting of diatomite and fly ash. About 12 m³ of ceramic media inoculated with waste activated sludge were filled in the biofilter. The experimental conditions were space velocity of 500 hr-1, empty bed residence time of 7.2 s, and linear velocity of 0.2 m/s. About 90 L/d of water were sprayed for the operation. The NH₃ concentration in inlet gases ranged from 8 to 90 ppmv. The concentration of H₂S ranged from 3.2-5.5 ppmv. The acclimation of the biofilter was slow, but more than 95% of removal efficiency was achieved after one month of operation. No nutrients were supplied to the biofilter. The pressure drop in the biofilter varied from 20-40 mmAq during the operation. The energy consumption of this biofilter was about 200 kW/d. It was estimated that the deodorization using this ceramic biofilter was successfully carried out to remove the odor emitted from composting facilities.