一体式中空纤维帘式膜生物反应器性能的研究

【作者】 李静；

【导师】 杜启云； 戴海平；

【作者基本信息】 天津工业大学 ， 材料学， 2004， 硕士

【摘要】 本文应用一体式中空纤维帘式膜生物好氧反应器进行了模拟废水实验研究，通过帘式膜组件在模拟废水中一系列运行试验及状况分析，考察了各种影响因素，重点对运行条件和操作参数进行优化设计，实验结果表明气水比在25：1，曝气量为3.0m³/h，污泥浓度在4～5g/L，水力停留时间为6～10h，曝气池内泥水混合液的温度在30℃，DO控制在2.0～3.5mg/L，pH在6.5～8.0，在曝气管为烧结管产生的均匀小气泡的作用下处理效果最理想，出水CODcr去除率达98％，BOD₅的浓度均＜10mg/L，平均去除率达到99％，出水平均浊度为0.297NTU，不进行人为排泥是可行的，帘式膜组件表现出了高效截留的特性，同时还探索了在膜两侧放置与膜平行的隔板后，隔板间距对整个系统的处理效果的影响，实验发现污水经过一个兼氧—好氧—兼氧这样的过程，使得此探索工艺具有某些A/O法的特征，并且在隔板间距为0.10 m时达到较佳的处理效果，尤其是提高了氮磷的去除效果，氨氮的去除率由原来的89％提高到92％，总磷去除率由原来最高达81％提高到平均去除率为83％，可见MBR具有去除含氮化合物和脱磷的特性，为实现MBR在较长泥龄下除磷提供了参考依据，为促进MBR得到实际的推广和应用提供优化方法和工程参数。 本文还研究了膜通量的衰减情况，数据表明使用后膜通量降低到初始膜通量的三分之一，膜污染比较严重，进行换向操作有利于减轻膜通量的衰减，单位膜面积膜通量平均提高了4.5L/（m²·h）。对污染之后的中空纤维膜的内部做电镜分析和红外光谱分析，表明膜的污染是不断变化的，其实际污染状态与当时的运行条件和混合液性质有关，与中空纤维膜丝的轴向特征、以及中空纤维膜丝的长度和直径有关，这方面还有待于进一步研究。 本文还采用MBR法对纺PVDF中空纤维工艺中处理添加剂产生的泡丝废水做了初步的探讨。首先对此废水进行厌氧生物处理，CODcr由31160mg/L降到1082mg/L，达到一定的降解目的之后再进入MBR体系，进行好氧生物处理，CODcr的平均去除率达到了93％，出水CODcr的平均值为89mg/L，BOD₅的平均去除率达到了99.3％，出水浊度均低于1.0NTU。初步实验证明，属比较难于降解的纺丝废水经过辅助的厌氧生物处理后采用MBR法处理是一种切实可行的方法，为纺丝废水的实际处理提供工艺参考和借鉴。更多还原

【Abstract】 This paper was studied on simulated wastewater by using submerged hollow fiber hanging curtain membrane bioreactor. Various influencing factors were reviewed by a series of operational condition and parameters and analyzing status according to hanging curtain membrane module running in the simulated wastewater. Optimized design to operational condition and parameters was put forward emphatically. The results under different operating conditions showed that the effluent qualities and effect of treatments of the MBR were the best while the ratio of A/W at 25:1,the amount of aeration was 3.0m3/h,the MLSS was at 4~5g/L,HRT was at 6~10h, the temperature of mixed solution in the aeration was 30癈,the range of dissolved oxygen concentration was 2.0~3.5mg/L, pH was 6.5~8.0,the even small air bubble was came from agglomeration pipe. And the average effluent removal efficiency of CODcr and BOD5 were respectively 98% and 99%, the concentration of effluent BOD5 was evenly less than 10mg/L, the average turbidity of effluent was 0.297NTU,proved that without man-made letting sludge was accomplished on feasibility and high effective retaining feature of hanging curtain was represented.The space between clapboards that placed the sides of membrane module and paralleled has great effect on the removal effect of the whole system based on experiments, it was found that the process of fultative aerobic-aerobic- fultative aerobic was happened and has some features of A/O. The removal effect was good while the space between clapboards was 0.10m,especially it improved the removal effect of nitrogen and phosphate, the removal efficiency of NH3-N increased from 89% to 92%, the removal efficiency of total phosphate raised from the maximum of 81% to the average of 83%, thus it can been seen that MBR took on the character of nitrogen compounds and phosphate removal, provided reference for MBR to realize phosphate removal at a longer sludge retention time and optimization method and engineering parameters for MBR to obtain actual propagations and application.The attenuation of membrane flux was also studied in this dissertation. The data showed that membrane flux after using decreased the third that of initial and explained membrane was polluted very severely. Changing orientation was in favor of alleviating the attenuation of membrane flux and membrane flux of unit of membrane area of membrane module advanced4.5L/(m2 h) averagely. Scan electron microscope was employed to observe and analyze theinner of hollow fiber membrane and made know that the pollution of membrane was changed constantly, that of practical pollution state had the relation with the temporal operation condition and the character of mixed solution, the axial feature of hollow fiber membrane thread, the length and diameter of hollow fiber membrane thread, this aspect was under study.This paper also had a pilot study on wastewater of immersed thread that rooted in dealing with additive in the process of PVDF filature adopting MBR. At first the wastewater was carried through applying to anaerobic biological treatment and obtained excellent removal effect, the concentration of CODcr decreased from 31160mg/L tol082mg/L. After arriving at the aim of some certain degrading degree, then came into MBR system, aerobic biological treatment was done, the average removal efficiency of CODcr and BOD5 were respectively 93% and 99.3%, the average effluent concentration value was CODcr 89mg/L, and the turbidity was averagely less than 1 .ONTU.The primary experiment proved that wastewater from filature hard to degrade could be applied to MBR tried by secondary anaerobic biological treatment, this feasible method could be reference technics and use for factual treatment of wastewater from filature.更多还原