Morphometric characterization of calcium sulfate dihydrate (gypsum) scale on reverse osmosis membranes
نویسندگان
چکیده
The axial development of calcium sulfate dihydrate (gypsum) scaling on selected reverse osmosis (RO) membrane surfaces was investigated experimentally in a plate-and-frame RO system. Scaling experiments with model solutions demonstrated progressive axial development of surface gypsum crystals along the membrane surface. The impact of surface crystallization was characterized via flux decline measurements and by both optical and high-resolution scanning electron microscopy (SEM) surface imaging. Surface coverage by gypsum scale (percent area covered and gypsum surface mass density) increased along the membranes (towards the membrane exit), consistent with the increase i n f r A a r t t ©
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