Title and Authors: Application of water super absorbents in biofiltration of n-hexane from air streams

فاقد چكيده

Water super absorbents are low cross linked hydrophilic polymers which absorb water up to several hundred times of their dry weight. In this research the effect of amending theses materials to the bed of a biofilter was investigated. For this purpose two equal size biofilters with the height of 50 cm, and the inner diameter of 5 cm were used. One of the biofilters was packed with a mixture of perlite and a poly acryl amide based super absorbent. The dry weight percent of the absorbent in the mixture was 2.3%. The other biofilter was packed with perlite as a control. With the inlet n-hexane concentration of about 1g.m-3, both biofilters were able to remove up to 90% of the entering pollutant. Under frequent moistening of the biofilters, there was no significant difference between the performances of the biofilters, but when less frequent moistening was applied, the super absorbent biofilter performed considerably better than the control one. After irrigation there was a temporary decrease in super absorbent containing biofilter probably due to the swelling of the absorbent which lowered the gas residence time. There was no leachate at the bottom of the super absorbent containing biofilter in contrast to the control biofilter.