Comparison between the environmental impacts of biotrickling filters and biofilters applied to waste bio-drying

A comparison between conventional open biofilters and biotrickling filters (BTFs) was carried out through a modeling activity to highlight their role on the air quality in the surroundings of a hypothetical municipal solid waste bio-drying plant. The AERMOD dispersion model was adopted to perform simulations of dispersion of two volatile organic compounds of interest for their impact in terms of odors and cancer risk: dimetil disulfide and benzene. Data on the input waste were retrieved from statistics of a province in the North of Italy. Using BTFs instead of conventional biofilters leads to significant improvements in the air quality around a bio-drying plant, quantifiable with a reduction of the annual mean concentrations higher than 90% in the vicinity of the plant. These improvements are achieved especially because of the higher release height of BTFs and the higher velocity of the outgoing air flow.