丙酮在固定化活性污泥凝胶颗粒内有效扩散系数的测定  

Determination of Effective Diffusion Coefficients of Acetone in Immobilized Activated Sludge Gel Beads

作　　者：赵康[1] 徐利行[1] 修光利[1] 张大年[1] 

机构地区：[1]华东理工大学环境工程系,上海200237

出　　处：《华东理工大学学报（自然科学版）》2008年第6期825-829,共5页Journal of East China University of Science and Technology

基　　金：上海市重点学科资助(B506);国家科技部十一五支撑计划(2006BAK20B01-5)

摘　　要：为研究不同凝胶颗粒的扩散性能和两种测定方法之间的差异，采用浸入法和浸出法，测定了丙酮在4种固定化海藻酸钙凝胶颗粒内的有效扩散系数，测定结果为1．4×10^-8～1．9×10^-8m^2／min。实验结果表明：对于丙酮，两种测定方法略有差别，浸出法测定的有效扩散系数的大小与颗粒投入蒸馏水时球体表面的丙酮多少有关系。浸入法中包埋粉末活性炭的凝胶颗粒比不包埋粉末活性炭的有效扩散系数大，而浸出法得到的结果与其相反。浸入法和浸出法均得出包埋活性污泥的凝胶颗粒比不包埋活性污泥的有效扩散系数要小的结论。Two types of diffusion experiments were performed to determine the effective diffusion coefficients （De） of acetone in four calcium alginate gel beads： blank/immobilized activated sludge beads prepared with and without adding powdered activated carbon （PAC） ; the calculated De values ranged from 1.4×10^-8-1.9× 10^-8 m^2/min. For the two PAC-added beads, the De values obtained using the inward diffusion method （Method I）, which employed clean beads/an acetone solution and produced profiles of declining acetone concentration, were higher than the equivalents of the outward diffusion method （Method II）, which employed acetone loaded beads/a clean water and produced profiles of increasing acetone concentration; for the two plain beads （no PAC）, the equivalent De values of the two methods were very close. Using Method I, PAC enhanced the inward diffusion process and thus resulted in higher D, values for the PAC-added beads relative to their equivalents of the plain beads; using Method II, PAC retarded the outward diffusion and resulted in lower De values. With and without PAC, acetone diffusion in the immobilized activated sludge beads was slower than that in the blank beads. The amount of the acetone pre-loading of the beads affected the De values of Method II. The inward diffusion method is recommended for estimating De in gel beads because it is simpler and more reliable.

关 键 词：固定化活性污泥 有效扩散系数 海藻酸钙 丙酮 

分 类 号：O636[理学—高分子化学] X511[理学—化学]