Use of compost as biological filter to remove gaseous hydrogen sulfide

Odor pollution is very popular in developing countries. Odors can arise from many different sources, cause discomfort to expose, and also have certain effects on health. Odors can come from the anaerobic digestion of waste, from a factory's wastewater treatment system, or from manufacturing operations in industries such as seafood processing or animal feed production, tanning, and rubber processing. The composition of the odor is often diverse with many gases, mainly in low concentrations. Because it is gaseous pollution, the odor has the risk of spreading widely, the collection must be carried out in a wide range, the flow of gas to be treated is often large. In this study, one of the basic components of odors, H2S, was of interest to be treated because of its prevalence and toxic nature. Currently, although there are many technologies to handle H2S, the application in odor treatment still has many shortcomings. The current technologies such as adsorption and absorption are not suitable for the removal of H2S in odor because of the low efficiency but high cost. In this study, a cheap and available commercial compost fertilizer was used for the removal of gaseous H2S in a lab-scale biofilter. Results showed that microorganisms had an avital role in H2S removal. The factors affecting the biological removal of H2S were determined to be relative humidity (RH), operation time, presence of mixing/turning, and height of compost column. The high H2S removal efficiency of 94.2% was obtained at RH of 50% and compost height of 400 mm, which is suggested for full-scale biofilter design. Under turning condition of once per two days for compost column, the biofilter system was stable at removal efficiency of over 80% during at least 12 days of operation.