Study On The Treatment Of Carbon Dioxide By Biotricking Filter Filled With Iron-Oxide Ceramics And Polyurethane Foam

CS2 as a typical volatile sulfur compond and industrial volatile organic compound, also as a toxic substance with low boiling point can lead the change in the whole body. It not only has toxic effects on the human body, will stay long in the atmosphere, and it can be oxidized to COS and other sulfate substances which will cause acid rain and lead to more toxic effects on lower atmosphere. Therefore, developing CS2 purification technology research and control measures are need urgently. In present study, CS2 was removal by using two biological trickling filter filled with attapulgite iron oxide porous ceramic (BFC) and new polyurethane foam (BFP) material respectively, to investigate the treatment performance of two trickling filter, the running time in start-up period, the effects of different operating parameters, the optimum operating conditions, the dominant microbial strains and the difference between the two trickling filter.The results showed that:(1) CS2 removal efficiency was stable in BFC and in BFP after 15th day and 13th day respectively, two trickling filter both substantially finished the start-up for biofilm formation within 30 days, CS2 processing performance of BFC was better than CS2 processing performance of BFP in the start-up period and the continuous running period. (2) In BFC, when the inlet concentration of CS2<400 mg/m3, inlet air flow rate of 80 L/h (EBRT= 211.9 s), circulating nutrient solution spray density of 34.38 mL/min, CS2 removal efficiency remained at 85% above, and 25.76 g/(m3·h) of maximum biochemical CS2 elimination capacity could be achieved. Similarly in BFP, when the inlet concentration of CS2<400mg/m3, inlet air flow rate of 80 L/h (EBRT= 211.9 s), circulating nutrient solution spray density of 26.56 mL/min, CS2 removal efficiency remained at around 80%, and 20.42 g/(m3·h) of maximum biochemical CS2 elimination capacity could be achieved. (3) The actual conversion rate of SO42-growth substantially linear proportionally in BFC and BFP with the relationship of increasing CS2 inlet load, and there was a certain difference between the theoretical conversion rate of SO42- and the actual conversion rate of SO42 which demonstrated CS2 was not only converted into SO42- in microorganisms biodegradation process, it could also be further converted to other substances such as sulfur elemental, sulphate and sulphite. (4) The degradation process of CS2 by biotrickling filter could better meet the Adsorption-Biofilm degradation model, wherein the correlation coefficient R2 in both biotrickling filter of CS2 inlet concentration, removal efficiency and biological elimination capacity were 0.963,0.956,0.996 and 0.961,0.919,0.989 respectively. (5)Gammaproteobacteria, Betaproteobacteria, Sphingobacteriia and Alphaproteobacteria strains played dominant role in BFC and BFP by the result of High-throughput sequencing. And Gammaproteobacteria was a predominant flora under the experimental conditions in BFC and BFP, the flora distribution of both two biotrickling filter was similar, but there were also some differences.