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931.
以成熟除磷颗粒污泥为基础,基于获得的最佳混合碳源配比,通过正交试验研究了复合底物[m(C)/m(N)/m(P)]对颗粒化EBPR系统稳定过程除磷特性的影响.结果表明,R2[m(C)/m(N)/m(P)=400∶10∶5]、R3[m(C)/m(N)/m(P)=600∶10∶10]、R5[m(C)/m(N)/m(P)=400∶20∶15]系统发生了丝状菌颗粒污泥膨胀;R6[m(C)/m(N)/m(P)=600∶20∶5]系统因出现大量颗粒碎片导致沉降性能变差,待颗粒碎片排出系统后恢复正常.R3、R8[m(C)/m(N)/m(P)=400∶30∶10]、R9[m(C)/m(N)/m(P)=600∶30∶15]系统的颗粒粒径从初始的0.8 mm逐渐下降至0.3 mm,其余系统则与初始相差不多.R1[m(C)/m(N)/m(P)=200∶10∶15]、R4[m(C)/m(N)/m(P)=200∶20∶10]和R7[m(C)/m(N)/m(P)=200∶30∶5]系统在厌氧段消耗了95%的COD,释磷/吸磷速率分别在60~100 mg·(g·h)-1、60~80 mg·(g·h)-1、40~60 mg·(g·h)-1的范围内波动,且相对稳定,但其余系统的COD由主要在厌氧段消耗逐渐变为在好氧段消耗,释磷/吸磷速率亦逐渐下降,甚至有系统下降至0 mg·(g·h)-1.R1~R9系统的磷酸盐平均去除率分别是83.5%、52.8%、7.1%、96.7%、19.7%、72.2%、79.7%、28.1%和48.7%.对正交试验结果应用方差分析,获得适合颗粒化EBPR系统稳定运行的最佳复合底物条件是m(C)/m(N)/m(P)=200∶20∶15. 相似文献
932.
933.
Performances of biological aerated filter employing hollow fiber membrane segments of surface-improved poly (sulfone) as biofilm carriers 总被引:2,自引:0,他引:2
SHEN Ying-jie WU Guang-xi FAN Yao-bo ZHONG Hui WU Lin-lin ZHANG Shao-lai ZHAO Xian-hong ZHANG Wei-jun 《环境科学学报(英文版)》2007,19(7):811-817
Using the surface of poly (sulfone) hollow fiber membrane segments as grafted layer, the hydrophilic acrylamide chain was grafted on by UV-photoinduced grafting polymerization. The gained improvement of surface wettability for the modified membrane was tested by measuring the contact-angle as well as FTIR spectra. Then correlation between the hydrophilic ability of support material and the biofilm adherence ability was demonstrated by comparing the pollutant removal rates from urban wastewater via two identical lab-scale up-flow biological aerated filters, one employed the surface wettability modified poly (sulfone) hollow fiber membrane segment as biofilm carder and the other employed unmodified membrane segment as biofilm carder. The experimental results showed that under the conditions of influent flux 5 L/h, hydraulic retention time 9 h and gas to liquid ratio (G/L) 10: 1, the removal rates of chemical oxygen demand (COD) and ammonium nitrogen (NH4^+-N) for the modified packing filter and the unmodified packing filter was averaged at 83.64% and 96.25%, respectively, with the former filter being 5%-20% more than the latter. The effluent concentration of COD, NH4^+-N and turbidity for the modified packing filter was 25.25 mg/L, 2 mg/L and 8 NTU, respectively. Moreover, the ammonium nitrogen removal performance of the filter packing the modified PSF was compared with the other bioreactor packing of an efficient floating medium. The biomass test indicated that the modified membrane matrixes provided better specific adhesion (3310-5653 mg TSS/L support), which gave a mean of 1000 mg TSS/L more than the unmodified membrane did. In addition, the phenomenon of simultaneous denitrification on the inner surface of the support and nitrification on the outer surface was found in this work. 相似文献
934.
螺旋对称流厌氧膜生物反应器的运行及优化 总被引:1,自引:0,他引:1
通过对螺旋对称流厌氧反应器(SSSAB)外置平板膜组件形成了螺旋对称流厌氧膜生物反应器(SSS-AnMBR).研究了SSS-AnMBR的启动阶段和有无沼气曝气时的运行性能,并建立了其设计与操作优化模型.在启动过程中,反应器内挥发性脂肪酸与碱度的比值为0.001~0.016,未发生酸化现象,后期反应器对化学需氧量(COD)的去除率稳定在90.27%~95.35%.有沼气曝气状态下SSS-An MBR的有机负荷和COD去除率分别为2.28 kg·m~(-3)·d~(-1)和98.24%,均高于无沼气曝气状态下的2.13 kg·m~(-3)·d~(-1)和97.58%,表明系统的污染物去除效能较好.有沼气曝气状态下膜组件的平均负荷、平均COD去除率和SSS-An MBR平均总COD去除率的CV值分别为21.98%、14.15%和0.78%,均低于无沼气曝气状态下的25.27%、21.98%和0.89%,表明该状态下系统稳定性较好.最后建立了厌氧反应器体积(V)、进水流量(Q)和进水COD(X)三者之间的数学模型:V/Q=HRT0/C_(inf)×η_(sss)(X-Cinf)+HRT_0,以及膜面积A与Q之间的数学模型:A=Q×C_(sss)×η_m/MLR,可指导同类型的厌氧膜生物反应器的设计和操作优化. 相似文献
935.
Removal of nitric oxide from simulated flue gas via denitrification in a hollow-fiber membrane bioreactor 总被引:1,自引:0,他引:1
Xinyu Zhang Ruofei Jin Guangfei Liu Xiyang Dong Jiti Zhou Aijie Wang 《环境科学学报(英文版)》2013,25(11):2239-2246
A hollow-fiber membrane bioreactor(HMBR) was studied for its ability to treat nitric oxide(NO) from simulated flue gas. The HMBR was operated for 9 months and showed a maximum elimination capacity of 702 mg NO/(m2·day) with a removal efciency of 86%(gas residence time of 30 sec, inlet NO concentration of 2680 mg/m3, pH 8). Varying operation parameters were tested to determine the stability and response of the HMBR. Both the inlet NO concentration and gas residence time influenced the removal of NO in the HMBR. NO elimination capacity increased with an increase in inlet NO concentration or a shortening of gas residence time. Higher removal efciency of NO was obtained at a longer gas residence time or a lower inlet NO concentration. Microbial communities of the HMBR were sensitive to the variation in pH value and alkalescence corresponding to an optimum pH value of 8. In addition, NO elimination capacity and removal efciency were inversely proportional to the inlet oxygen concentration. Sulfur dioxide had no great influence on elimination capacity and removal efciency of NO. Product analysis was performed to study N2O and N2 production and confirmed that the majority of the microorganisms were denitrifying bacteria in the HMBR. Compared to other bioreactors treating NO, this study showed that the denitrifying HMBR was a good option for the removal of NO. 相似文献
936.
Exponential relationship was developed to quantify the normalized membrane flux dynamics during the filtration period and fitted the results well. 相似文献
937.
我国餐饮废水处理方法的研究进展 总被引:3,自引:0,他引:3
综述了我国餐饮废水的处理方法,具体分析和比较了生物降解、膜生物反应技术、混凝法和电化学法的优缺点。指出组合物理、化学和生物法,将是解决我国餐饮废水污染问题的最佳途径,并对今后我国餐饮废水处理技术研究方向进行了展望。 相似文献
938.
939.
一体式膜生物反应器中膜污染影响因素的研究 总被引:2,自引:0,他引:2
膜污染是一体式膜生物反应器(SMBR)工艺中普遍存在的问题,是SMBR稳定运行和膜寿命的关键影响因素.影响膜污染的因素包括以下几个方面:膜的特性(膜材质、膜孔径的大小及表面粗糙度等);膜组件的类型与结构;SMBR的运行条件(膜通量、抽吸泵抽停时间、曝气量与曝气方式、出水方式与水力停留时间等);污泥特性(污泥浓度、微生物的溶解性产物和胞外聚合物以及污泥龄等).改善膜和污泥的特性、优化SMBR的结构及运行操作参数能够减缓膜污染. 相似文献
940.
腐殖酸溶液对超滤膜污染的原因研究 总被引:2,自引:0,他引:2
针对腐殖酸溶液对超滤膜污染的原因,对超滤膜在过滤腐殖酸溶液时受到污染的变化进行了探讨,通过测试的数据比较了待测腐殖酸溶液与膜通量的关系,同时对腐殖酸溶液和添加钙离子后,对超滤膜污染的影响状况,同时还对超滤膜在过滤过程中的UV254变化规律进行了探讨。结果表明,不同质量浓度的腐殖酸溶液,它们对膜通量的影响比较显著,在相同的过滤时间内,膜通量分别下降了不同的百分组成。在腐植酸溶液中添加钙离子后,膜通量下降更大。 相似文献