What is the main purpose of a biofilter used for odor control at a landfill?

The main purpose of a biofilter used for odor control at a landfill is to remove odorous compounds from landfill gas or air emissions by biologically degrading them using microorganisms. A biofilter consists of a bed of porous material, such as compost, wood chips, or soil, that is inoculated with microorganisms. Odorous air is passed through the biofilter bed, and the microorganisms consume the odorous compounds as a food source, converting them into less offensive substances such as carbon dioxide, water, and biomass. Biofilters are effective at removing a wide range of odorous compounds, including hydrogen sulfide (H2S), volatile organic compounds (VOCs), and ammonia. The effectiveness of a biofilter depends on factors such as the type of filter media, moisture content, temperature, pH, and the concentration of odorous compounds. Biofilters offer an environmentally friendly and cost-effective alternative to other odor control technologies, such as activated carbon adsorption or chemical scrubbing. They are particularly well-suited for treating large volumes of air with relatively low concentrations of odorous compounds. Regular monitoring of the biofilter's performance is essential to ensure its continued effectiveness.