自养型生物过滤器硝化氧化一氧化氮

采用一种新的工程材料多孔碳作为填料,在3个φ50.8mm填充着不同孔径多孔碳和驯化培养好的自养型亚硝酸盐硝化菌的生物过滤器中,进行了净化气体中NO的探索性研究.实验采用亚硝酸盐为唯一氮源,在多孔碳的表面培养生物膜,采用超声波气溶胶发生器来维持过滤器内的湿度并保持多孔碳表面液膜的厚度较小.液相硝化试验用来比较3种不同孔径的多孔碳之间硝化性能的潜力和差异结果表明,在亚氮(NO₂^--N)进口负荷约200～800g/(L·min)的范围内.24孔/cm(Pores Per Centimeter,PPC)多孔碳过滤器的硝化速率最大,达到94%～98%;8PPC和18PPC多孔碳过滤器的硝化速率分别达到15%～21%和30%～40%.气相试验表明,在NO空床停留时间3.5min、进口浓度66.97～267.86mg/m³的范围内,24PPC多孔碳过滤器对NO的去除效率为41%～52%左右,表明了该自养硝化系统在NO废气治理中的应用潜力.

Autotrophic Biofilters for Oxidation of Nitric Oxide

Carbon foam, a kind of new engineering material as packing material was adopted in three fi 50.8 mm biofilters with different pore dimension and a domesticated autotrophic nitrite nitrobacteria to investigate the purification of nitrie oxide(NO) in air stream. The biofilm was developed on the surface of carbon foams using nitrite as its only nitric source. The moisture in the filter was maintained by ultrasonic aerosol equipment, which can also minimize the thickness of the liquid film. The liquid phase nitrification test was conducted to determine the variability and the potential of performance among the three carbon foam-based biofilters. The investigation showed that during the NO influent concentration of 200 to 800 g/(L.min), the 24PPC (Pores Per Centimeter) carbon foam-based biofilters had the greatest potential, achieving removal efficiencies of 94% to 98%. The 8PPC and 18PPC carbon foam-based biofilters achieved removals efficiencies of 15% to 21% and of 30% to 40%, respectively. Further research showed the potential for this system to remove NO from an air stream on the base of a steady removal efficiency of 41% to 52% was attained for the 24PPC carbon foam-based biofilter at specified NO influent concentrations of 66.97 to 267.86 mg/m3 and an empty-bed residence time of 3.5 minutes.