自生生物动态膜反应器处理城市污水特性研究

【作者】 吴季勇；

【导师】 高运川；

【作者基本信息】 上海师范大学 ， 环境科学， 2004， 硕士

【摘要】 实验采用0.1mm孔径的筛网自制膜组件构成自生生物动态膜反应器对模拟城市污水进行研究。实验考察了自生生物动态膜的形成和再生，以及膜孔径、膜通量和污泥浓度对自生生物动态膜形成的影响。在HRT=4h，膜通量为20.8L m^-2h^-1，MLSS在4000mg／L时研究自生生物动态膜反应器对模拟城市污水长期稳定处理效果和机理，同时研究了水力停留时间对处理效果的影响和系统的抗冲击能力。通过实验计算了自生生物动态膜过滤阻力的分布，并研究了膜污染防治措施。通过与传统活性污泥工艺和一体式膜生物反应器进行比较，对自生生物动态膜反应器进行了技术经济评价。 实验结果表明，在HRT=4h，膜通量为20.8L m^-2h^-1，MLSS在4000m/L时，系统稳定运行了40天，出水水头压差保持在9mm左右，在稳定运行期间，出水的SS未检出，浊度均小于5NTU，氨氮的去除率保持在80％以上，COD平均去除率为87％，膜分离对有机物也有一定的去除作用，平均去除率为18％，膜分离对部分有机物的截留作用使系统具有良好的抗浓度和水力冲击能力。自生生物动态膜可在48小时左右形成，包括滤饼层和凝胶层，其中滤饼层在10min左右即可形成，而凝胶层的形成是一个相对较缓慢的过程，通过扫描电镜观察凝胶层主要由丝状菌构成。而自生生物动态膜的再生可在50min左右完成。自生生物动态膜的过滤阻力R较小仅为1.5×10¹⁰m^-1，比普通膜生物反应器小2～3个数量级，自生生物动态膜的过滤阻力主要由滤饼层贡献，其占总过滤阻力90％以上。空曝气即可有效的控制膜污染，当空曝时间为2min时，膜通量可恢复到72％。更多还原

【Abstract】 The self-forming bio-dynamic membrane reactor （SFDMR） was equipped with a l00μm nylon mesh as filter material instead of a micro-filtration membrane in membrane bioreactor. We had observed the formation and recovery processes of SFDM, effects of pore sizes, flux and MLSS on the formation of SFDM. The artificial domestic wastewater was fed to the reactor to examine the long-term effect and the mechanism of treatment when HRT = 4h, flux = 20.8L m-2h-1 and MLSS = 4000mg/L. The paper discussed the impact of HRT on the treatment and the ability of anti-shock. The distribution of filtration resistance was accounted during experiment, and harnessing measure of fouling of membrane was also studied. Through the comparison between the CAS and MBR, we made technological and economic assessment on SFDMR.The experiment showed that a very good effect of removal could be seen using the SFDMR to treat domestic wastewater. System could work steadily 40 days at a pressure as low as 9mm water head drop. During the steady running, conclusion from the results of investigation was that SS concentration could not be monitored, turbidity of effluence was less than 5NTU, and the removal rates of COD and NH3-N were above 80% and 87% respectively. The self-forming bio-dynamic membrane could form in 48h, including cake layer and gel layer, and cake layer could form in l0min. the formation of gel layer was a slower process. Gel layer was composed by filamentous by SEM. The filtration resistance of SFDM was only 1.5xl0¹0m^-1, exponentially two or three times smaller than MBR. The resistance caused by cake layer contributed above 90% to the total filtration resistance of the SFDM. Aerating was conducted to control membrane fouling. When aerating time was 2min, flux could be resumed to 72%.更多还原