Dynamic behavior of compost biofilters during periods of starvation and fluctuating hydrogen sulfide loadings.

To understand transient-state performance of biofilters and the phenomena occurring during changes and interruptions in their operating conditions, dynamic behavior of biofilters exposed to shock loadings of contaminant (H2S) and periods of starvation has been investigated. The initial startup and the response of the biofilters to step changes in the H2S concentration and air-loading rate were also presented and discussed. Biofilters responded very effectively to H2S concentration spikes at H2S mass loading rates of 19.8-48.0 g/m3h by rapidly recovering their original removal rates within 1.2-20.2 min. The recovery time after each spike showed a positive correlation to the total amount of H2S loadings during the spike. Biofilters showed capabilities of withstanding 11-28 days of starvations and recovered their full performances after the starvations without any evident lag period.