Complete NO_x and SO2 Treatment in a Biotrickling Filter - Bioreactor System

摘要

Complete treatment of sulfur dioxide (SO2) from flue gases in a two-stage process consisting of a biotrickling filter followed by biological post-treatment unit was investigated. The biotrickling filter could remove 100% of influent SO2 from simulated flue gas at an empty bed residence time of 6 s for a concentration range of 300-1000 ppm_v. All the absorbed SO2 was recovered in the biotrickling filter liquid effluent as sulfite (a product of chemical reaction of SO2) and sulfate (product of biological oxidation of sulfite). The biotrickling filter liquid effluent was further processed biologically in a post-treatment unit consisting of a combined anaerobic and microaerophilic reactor fed with glucose as a carbon source for sulfate and sulfite reduction. The post-treatment unit could effectively treat the trickling water to produce elemental sulfur. The sulfur production efficiency of the reactor reached about 80% of the SO2 treated. The biological treatment system seems to be a promising alternative for flue gas desulfurization.