Removal of NH and HS from odor causing tannery emissions using biological filters: Impact of operational strategy on the performance of a pilot-scale bio-filter.

Deodorization of gases emitted from Tanneries using eco-friendly and cost-effective approaches is necessary for the safe disposal of industrial emissions. There is limited research available on the treatment of odorous gases emitted from tanneries using bio-filter. In this endeavor, pilot-scale studies were performed in a 2.7 m bio-filter with synthetic gas mixture containing hydrogen sulfide (HS) and ammonia (NH) as input gas to study the impact of bedding material for the removal of HS and NH using bio-filter and identification of various design parameters for scale-up. The pilot-scale studies showed that the removal efficacy of both NH and HS was about 90-99% at an empty bed residence time of 55 seconds at an inlet concentration (NH and HS) of 200 to 210 ppmV and microbial count enhanced from 3.5 × 10 to 8.9 × 10 in 210 days. The microbial biodiversity analysis revealed the dominance of as as well as and . A full-scale bio-filter (13.75 m) was designed, installed, and commissioned in a tannery and observed that the removal efficiency of >99% since last three years.