ポリアミド系複合逆浸透膜の膜性能にフミン酸によるファウリングが与える影響

抄録

An element of fully aromatic polyamide composite reverse osmosis membrane was taken from a desalination plant after being used for three years, and fouling behavior of the used membrane by Aldrich humic acid was investigated. It was found that the presence of Ca²⁺ significantly induced water flux decline for both virgin and used membranes. Additionally, compared to virgin membranes, more severe water flux decline was observed for used membranes which are coated with less amount of polyvinyl alcohol. Regarding the rejection of contaminants, the rejection of Cl^- and NO₃^- gradually increased when the feed solution which contains Aldrich humic acid was treated; this trend was not observed for H₃BO₃. The analysis of experimental data using the solution-diffusion model which allows for the existence of unhindered advection through nano-scale imperfections showed that the increase in the Cl^- and NO₃^- rejection was due to the clogging of nano-scale imperfections by Aldrich humic acid.