基于硫酸盐还原菌作用的油菜秆固定床处理模拟含Cr（Ⅵ）废水

探讨了固定床除Cr工艺以油菜秆为微生物生长的缓释碳源,含SRB的混合微生物和油菜秆对Cr（Ⅵ）的还原和固定的共同作用。动态实验分2阶段开展：初始2周的驯化阶段和梯度增加Cr（Ⅵ）浓度的除Cr实验阶段。除Cr实验中,间歇对固定床出水pH、氧化还原电位、SO42-及硫化物浓度、DOC、Cr（Ⅵ）浓度进行测试,实验结束后对固定床中固体产物进行SEM、EDS和XPS等分析。结果表明,油菜秆固定床处理模拟含Cr（Ⅵ）废水效果明显。当进水Cr（Ⅵ）浓度ρ[Cr（Ⅵ）]〈19.52 mg/L时,出水Cr（Ⅵ）和Cr（Ⅲ）浓度均低于排放标准（0.05 mg/L）;Cr（Ⅵ）被还原为Cr（Ⅲ）,Cr（Ⅲ）以氢氧化物的形式沉淀附着于油菜秆和其它固体物质之上。分析认为,油菜秆在固定床处理模拟含Cr（Ⅵ）废水中所起的作用主要包括3方面（作为微生物生长的缓释碳源;吸附Cr（Ⅵ）,降低其对微生物的毒性;作为Cr（Ⅲ）矿化产物的沉淀附着界面）;Cr（Ⅵ）主要通过SRB的直接作用及H2S的作用被还原为Cr（Ⅲ）;以油菜秆为碳源的固定床处理Cr（Ⅵ）的浓度上限介于15.05～19.52mg/L之间。     

瓯江杨府山边滩围垦工程试验研究

瓯江杨府山河段边滩发育丰富，底沙运动频繁，悬沙含量高，对边滩围垦促淤极为有利。本文依据大量的水文、泥沙、地形等实测资料，在模型验证试验相似的基础上进行围垦工程试验，分别论证其工程的可行性、工程布置形式的促淤效果。对类似的边滩围涂工程具有借鉴作用。     

An experimental study of dispersion of an interactive tracer in chemically heterogeneous medium at a column scale

This paper aims at examining the increase of phenol adsorption breakthrough curves spreading caused by the chemical heterogeneity of granular activated carbon fixed beds. The local and the thermodynamic equilibrium assumption, as well as the nonlinear adsorption obeying to Langmuir isotherm, are considered. This study particularly tempts to link the reduced variance of phenol breakthrough curves to a measurable quantifying parameter of the chemical heterogeneity. The investigated artificial heterogeneous media are prepared by alternating layers of two types of granular activated carbon, active and non-active ones, that have similar physical properties. On the one hand, the chemical heterogeneity is quantified by the active layer relative thickness of the column length, l₁/L. On the other hand, it is quantified by the mean value of the probability distribution γ. The latter also represents the mean active grains mass ratio of the total medium mass, hence the medium mean capacity. The obtained results show an increase in the reduced variance and thus the effective global dispersion with the heterogeneity; the increase is as important as the medium capacity decreases. However, the dispersion increase achieves a limit value, even when the heterogeneity increases. The results are statistically modelled using a regression equation function of the capacity variation in terms of γ and the chemical heterogeneity in terms of l₁/L. The relationship combining the medium capacity and the chemical heterogeneity is obtained. The relationship implicitly takes into account the effect of the column length.     

上海洋山港区定床泥沙模型试验研究

通过定床泥沙模型试验,研究洋山港区总体规划两种方案和一期工程三种方案的工程实施后港池泥沙淤积情况,以及外航道浚深段年平均淤积强度和维护挖泥数量.