Efficacy of a novel biofilter in hatchery sanitation: II. Removal of odorogenous pollutants

The present research assessed the treatment effi ciency of odorogenous pollutants in air from a hatchery hall vented on organic and organic-mineral beds of an enclosed-container biofi lter. In this study, the following media were used: organic medium containing compost and peat (OM); organic-mineral medium containing bentonite, compost and peat (BM); organic-mineral medium containing halloysite, compost and peat (HM). The concentration of odorogenous gaseous pollutants (sulfur compounds and amines) in the hatching room air and in the air after biotreatment were determined by gas chromatography. In the hatchery hall among the typical odorogenous pollutants, there were determined 2 amines: 2-butanamine and 2-pentanamine, hydrogen sulfi de, sulfur dioxide, carbon disulfi de, sulfi des and mercaptans. Ethyl mercaptan showed the highest levels as its mean concentration in the hatchery hall air exceeded 60 μg/m3 and in single samples even 800 μg/m3. A mean concentration of 2-butanamine and sulfur dioxide in the examined air also appeared to be relatively high – 21.405 μg/m3 and 15.279 μg/m3, respectively. In each fi lter material, the air treatment process ran in a different mode. As the comparison reveals, the mean reduction of odorogenous contaminants recorded in the hall and subjected to biotreatment was satisfying as it surpassed 60% for most established pollutants. These high removal values were confi rmed statistically only for single compounds. However, a low removal level was reported for hydrogen sulfi de and sulfur dioxide. No reduction was recorded in the bentonite supplemented medium (BM) for sulfur dioxide and methyl mercaptan. In the organic medium (OM) no concentration fall was noted for dipropyl sulfi de either. In all the media investigated, the highest removal rate (100%), not confi rmed statistically, was observed for carbon disulfi de. Very good results were obtained in the medium with a bentonite additive (BM) for both identifi ed amines, whose mean elimination rate exceeded 60% (p≤0.05). The present research proved that diethyl sulfi de is most susceptible to biofi ltration (over 80%) in the bed supplemented with halloysite (HM) and bentonite (BM) (p≤0.05).