【作者】 卓琳云；

【导师】 陈季华；

【作者基本信息】 东华大学 ， 环境工程， 2005， 硕士

【摘要】 本文以平均表面孔径约2μm的陶瓷膜为基质,对动态膜进行了一系列研究,初步确定动态膜的运行条件,并将其应用于处理高浓度含氮废水的分体式膜—生物反应器中。主要考察了动态膜的涂膜材料、涂膜条件、处理污泥后被污染的动态陶瓷膜的清洗过程和清洗条件、动态膜处理二级出水和污泥时的运行参数以及动态膜在分体式膜—生物反应器中的运行结果。整个过程中,需要测定的参数有:出水通量、出水效果(COD、SS、浊度、氨氮、硝态氮)以及分体式膜—生物反应器运行过程中的污泥浓度、好氧呼吸速率等。 首先选择实验用的动态膜涂膜材料,发现经高岭土涂膜后的膜管出水通量和恢复效果以及对二级出水的处理都较好,所以选择高岭土进行后续研究。实验选择粒径较小的6000目高岭土作为涂膜材料;涂膜条件为错流速度0.5m/s,跨膜压力0.2MPa和涂膜液浓度0.3g/L;涂膜10～20min后基本上达到平衡,即可制得较为稳定的动态膜。 在对膜管的污染机理研究中,通过分析膜的阻力结构,得出可逆阻力是膜管总阻力的主要组成部分;对膜污染成分进行了较详细的分析,得出膜污染成分中主要存在的是钙镁盐;选择动态膜污染后的清洗过程和条件:高速冲洗—自来水反冲—碱洗(0.2mol/LNaOH)1小时—酸洗(0.1mol/LHCl)1小时;经过反复清洗,膜管通量恢复都在更多还原

【Abstract】 The experiments on the 2 μ m ceramic membrane are carried out to confirm the running condition of dynamic membrane and then treat nitrogenous wastewater in a heavy concentration in such a RMBR. This paper studies the appropriate material of dynamic membrane, the optimistic formation conditions of dynamic membrane, the cleaning-up process of polluted dynamic inorganic membrane, the running condition in treating secondary effluent and sludge and the running efficiency of RMBR as well. The permeating flux COD_Cr SS, turbidity value, NH₄⁺-N, NO₃^--N, NO₂^--N, MLSS, MLVSS and OUR （Oxygen Uptake Rate） are measured during experiments.Kaolin was first chosen as the membraning material, because experiments showed that the kaolin dynamic membrane had higher permeating flux than diatomite, wollastonite and heavy calcium carbonate, and kaolin dynamic membrane was more easily renewed after cleaning. With kaolin Particle size increasing the permeating flux went up correspondingly; considering the rejection of little-size molecule, 6000 mesh kaolin was better. The dynamic membrane was formed by circulating0.3g/L of kaolin in 10 minutes under the transmembrane pressure of 0.2MPa and at a crossflow velocity of 0.5m/s.The polluted ceramic membrane was cleaned by high speed flushing - back flushing-flushing with alkali （0.2mol/L NaOH） 1 h-flushing with acid （0.lmol/L HC1） 1 h. As a result the membrane flux would be restored up to 90%. It was proved that the dynamic membrane had a better restoration than the bare tube after the same cleaning process.Secondary effluent and sludge were treated under the transmembrane pressure of 0.2MPa and at a crossflow velocity of lm/s. Considering the permeating flux and the pollutant rejection the kaolin dynamic membrane are much better than bare tubes.We used the kaolin dynamic membrane to treat a kind of heavy-concentration nitrogenous wastewater in a RMBR that was steadily run in 2 mouths. As a result, the average COD_Cr and NH/-N concentration of system effluent were less than 20mg/L and 5mg/L, respectively. The removal rate of COD_Cr was 98.85%. In this RMBR, the NO₂^--N concentration was lower than NO₃^--N. The amount of sludge increased slowly and finally the sludge concentration maintained 6500mg/L. In addition, the OUR fluctuated frequently but generally rose with the sludge concentration increasing. In brief, the permeating flux in RMBR was higher than in normal MBR system and the performance of ceramic membrane would be renewed well after flushing. However, the systemneeds periodic high-speed flushing and back flushing when the permeating flux decreased to lower than 10 L/（m² · h）.更多还原