石英砂均质滤料气水反冲洗试验研究

本文根据西安市曲江池水厂的净水工艺,对石英砂均质滤料层气水反冲洗作了试验研究.根据滤柱试验结果,提出了有效的气水反冲洗参数,即单独气冲强度为15～18L/(m^2·s),历时3min;气水混冲时,空气强度为15～18L/(m^2·s),水的强度为4L/(m^2·s),历时4min;清水漂洗强度为4L/(m^2·s),历时4min.

Analytical solution for concentration distribution in an open channel flow with phase exchange kinetics

This study is about an analytical attempt that explores the two-dimensional concentration distribution of a solute in an open channel flow.The solute undergoes reversible sorption at the channel bed.The method of multiple scales is used to find the two-dimensional concentration distribution,which is important for modem day application in industry,environmental risk assessment,etc.Study deduces an analytic expression of two-dimensional concentration distribution for an open channel flow with sorptive channel bed.Effects of retention parameter,Darnkohler number on the solute dispersion are also discussed in this paper.Results reveal that slow or strong kinetics(small value of Darnkohler number)increases solute dispersion.It is also observed.that for slow phase exchange kinetics between bulk flow and small retentive channel bed,solute concentration distribution will uniform faster than their inert counterpart.