PF-MBR处理城市生活污水膜污染特性研究

摘要

In the process of using MBR for treating wastewater, the problem of membrane fouling has existed extensively. The PF-MBR that can be used for treating municipal sewage is designed and made by adding powdered magnetic ferrite to the home-made MBR. The effect of adding powdered magnetic ferrite on membrane fouling is researched, and its mechanism is analyzed. The results show that adding powdered magnetic ferrite can retard membrane fouling to a certain extent. When the MBR-B without powdered magnetic ferrite added runs for 30 d,its transmembrane pressure is 22.9 kPa. But the transmembrane pressure of MBR-A with powdered magnetic ferrite added is only 17.2 kPa. The membrane filtration resistance of MBR-A is 1.65×l012m-1 less than that of MBR-B. The determining value of critical flux also demonstrates that adding powdered magnetic ferrite to MBR can retard membrane fouling. The mechanism analysis shows that adding powdered magnetic ferrite has changed the structure and property of activated sludge floe and lowered the resistance produced by the cake layer of membrane surface and the resistance produced by membrane pore plugging and adsorption, in the running process of MBR. Thus, membrane fouling is retarded effectively. The experiments of using the home-made magnetic ferrite powder indicates that it can make the waste recycling come true.%在膜生物反应器处理污水过程中,广泛存在膜污染问题.自制膜生物反应器,向其中添加磁性铁氧体粉末,组成铁氧体粉末膜生物反应器(PF-MBR),并用其处理城市生活污水;研究了添加磁性铁氧体粉末对膜污染的影响,并进行机理分析.研究结果表明,添加磁性铁氧体粉末能一定程度上延缓膜污染.不加磁性铁氧体粉末的MBR-B运行到第30天时膜过滤压差达到22.9 kPa,而添加磁性铁氧体粉末的MBR-A膜过滤压差只有17.2 kPa;MBR-A的膜过滤阻力比MBR-B的低1.65×1012m-1.临界通量测定结果也表明,向膜生物反应器中添加磁性铁氧体粉末能减缓膜污染.机理分析表明,向膜生物反应器中加入磁性铁氧体粉末改变了活性污泥絮体的结构和性质,降低了膜生物反应器运行过程中膜表面泥饼层产生的阻力及膜孔堵塞与吸附产生的阻力,从而有效缓解了膜污染.实验采用自制的磁性铁氧体粉末,可实现废物的资源化利用.