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Effect of cake resistance by first-aggregation of in-line injection system  

KIM, Taeyoung (KAIST 건설 및 환경공학과)
PARK, Heekyung (KAIST 건설 및 환경공학과)
Publication Information
Journal of Korean Society of Water and Wastewater / v.22, no.3, 2008 , pp. 281-288 More about this Journal
Abstract
Cake resistance is influenced by floc size deposited on membrane surface. Enlarging floc size can reduce cake resistance. The small particles are enlarged by coagulation and flocculation process in conventional mixing tank at membrane filtration system. Fully-grown flocs for reducing the cake resistance, however, are ruptured while passing through a pump. In light of this fact, this study aims to experimentally look at the reaggregation phenomenon of mixing system. In addition, reaggregation phenomenon of mixing system is compared with first-aggregation of in-line injection system in which coagulant is injected just before a pump. These results suggest that first-aggregation of in-line injection system is better than reaggregation of mixing system for G-value above $3100sec^{-1}$. Since G-value in pipe of actual membrane filtration system are usually larger than $3100sec^{-1}$. The performance of in-line injection system is expected to be better than the conventional mixing tank system.
Keywords
In-line injection system; First-aggregation; Cake resistance; Representative particle size;
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Times Cited By KSCI : 1  (Citation Analysis)
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