【作者】 杨国华； 周江华；

【Author】 YANG Guohua, ZHOU Jianghua, (Ningbo University, Ningbo 315211, China)

【机构】 宁波大学；

【摘要】 为了解决单层滤料床高过滤效率和高床层容尘量不能兼得的矛盾,试验研究了双层滤料颗粒床过滤器。该颗粒床以2￣5mm膨胀珍珠岩颗粒为上层滤料、0.5￣1mm海沙为下层滤料。试验表明,膨胀珍珠岩层具有体积过滤特性,用20%的床层压降承担了90%的床层容尘量,使床层容尘量达到了单层沙床的10倍。细沙层具有表面过滤特性,利用其表面形成的粉尘膜,使过滤效率达到99.99%以上。图2表3参2更多还原

【Abstract】 To overcome the contradiction of collection efficiency with dust-retaining capacity in a single-medium granular bed filter, a new dual-medium granular bed filter for hot gas clean up was invented and studied experimentally. Fine sand of 0.5mm~1mm was used as its lower layer of filtering medium and the expanded pearlite of 2mm~5mm as its upper layer of filtering medium in this study. Test results show that the filtration of the expanded pearlite layer was characterized as “volume filtration”, and the fine sand as “surface filtration” like bag house. The combination of “volume filtration” and “surface filtration” of the dual -medium granular bed filter resulted in both high collection efficiency and high bed dust-retaining capacity. The expanded pearlite layer had a contribution of about 90% to the bed dust-retaining capacity but only about 20% to the total bed pressure drop, which made the bed dust-retaining capacity be 10 times of that of the single-layer bed of the same sand. The dust membrane on the surface of the fine sand layer made the filtration efficiencies over 99.99%. Figs2, tables3 and refs2.更多还原