深床过滤颗粒截留机理研究

对深床过滤过程中颗粒物与滤料之间的相互作用进行了理论分析,讨论了两者间的相互作用及影响因素对微絮凝深床过滤进行了中试研究,考察了1～l0μm粒径颗粒在500cm滤床中的截留情况,并连续65h监测滤柱水头损失的变化;在滤速为24m/h情况下,计算了1～10μm粒径颗粒所受的水流剪切力;利用理论分析,分别讨论了表面电位为-25mV及-125mV、粒径为1～10μm的颗粒与滤料之间的物理化学作用力.理论计算值对实验结果进行了很好的解释,说明可以通过颗粒与滤料间的作用力分析来研究均质滤料深床过滤运行规律.

Particle Entrapment Mechanism in Deep Bed Filtration

Theoretical analysis was carried out in this paper to study the interaction in the bed filtration process, and the physico-chemical forces between the filter media and suspended particles in water were presented. Pilot study of the micro-flocculation deep bed filtration was carried out in the No. 9 Potable Water Treatment Plant of Beijing, the interception of particles of 1-10 microns diameter in the 500 cm deep filter bed was analyzed, and the head loss variation during 65 h was monitored. The shear force of 1-10 microns diameter-particle under 24 m/h filtration velocity was calculated. The theoretical physico-chemical forces between the filter bed and suspended particle of 1-10 microns diameter under the condition of -25 mV and -125 mV surface potential was also presented. The theoretical results are reasonably consistent with the experimental data, from which it can be concluded that the operation principles of micro-flocculation deep bed filtration could be analyzed by the physico-chemical interaction between the particles and filter media.