Biofiltration of Mixtures of Dimethyl Sulfide and Methanol for treating Exhaust Gases in the Pulp and Paper Industry

摘要

There is considerable interest in technologies that can effectively treat total reduced sulfur (TRS) emissions from waste gases and thereby reduce odorous emissions. Biofiltration is a cost-effective and environmentally attractive technology that is widely used to treat odors and VOCs in several industries. Our interest is in applying this to the pulp and paper industry where one frequently finds dimethyl sulfide (DMS) and methanol (MeOH) together. The objective of this study is to examine the effect of methanol on the biofiltration of DMS with the goal of developing an optimal technology to remove both compounds. Both batch experiments and long term continuous experiments in biofilters packed with inorganic media were conducted to assess the effects of methanol (MeOH) on the biofiltration of dimethyl sulfide (DMS) at various conditions. The continuous experiments clearly show that MeOH has a positive effect on the biofiltration of DMS and enhance DMS removal likely by supporting biomass growth as an additional carbon source. However, after the biofiltration of DMS with a MeOH loading of 12 g m~(-3) h~(-1) reaches steady state, a suspension of MeOH addition causes a quick increase of DMS removal in a short period. This suggests a competitive effect of MeOH on DMS biodegradation, which is also supported by the results from the batch experiments. Therefore this study suggests that there exists an optimum mix of DMS and MeOH for the treatment of DMS emissions. In the biofiltration of DMS and MeOH mixtures, the removal of MeOH was very rapid and high removal efficiency of MeOH was achieved.