Relationship between Moisture Behavior and Gaseous Volatile Organic Compounds Removal in a Biofiltration System

Abstract

Studies on the relationship between moisture behavior and gaseous VOCs (Volatile Organic Compounds) removal efficiency of packed tower biofilters are limited. In this research, the nutrient holding capacity, moisture evaporation rate and gaseous toluene and MEK (Methyl Ethyl Ketone) removal efficiencies of bioreactors with porous synthetic resin as the packing material were simultaneously observed. The nutrient holding capacity in one of the reactors was higher than those of the other two because its packing layer was frequently supplied with a nutrient solution by soaking. This reactor exhibited the highest toluene removal efficiency. However, excessive biomass growth was observed in this reactor. The reactor with a less frequent supply of nutrient solution by soaking showed a slightly lower toluene removal efficiency, possibly due to lack of nutrients in the packing layer. The reactor that was fed with the nutrient solution by spraying it onto the packing layer (a common method for supplying moisture) had the lowest toluene removal efficiency, mainly because of the uneven distribution of nutrients. Moreover, the moisture evaporation rate in the packing layer during moisture supply and heat balance were determined.