کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
643095 | 884356 | 2010 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Membrane distillation-crystallization of seawater reverse osmosis brines Membrane distillation-crystallization of seawater reverse osmosis brines](/preview/png/643095.png)
This work aims at investigating the performance, in terms of water recovery and NaCl crystallization kinetics, of a membrane distillation-crystallization (MDC) bench-scale plant operated on brines discharged from a seawater reverse osmosis (RO) unit.Experimental tests carried out on artificial RO concentrates resulted in the production of 21 kg/m3 of NaCl crystals, exhibiting substantially a ordinary cubic shape with size between 20 and 200 μm; the final water recovery factor increased up to 90%. Analogous investigations carried out on RO brines from natural seawater were affected by the presence of dissolved organic matter, showing a 20% reduction of the amount of salt crystallized, and a 8% decrease of the transmembrane flux.Growth rate of sodium chloride crystals generated from natural RO brines varied between 0.8 × 10−8 and 2.8 × 10−8 m/s; these values were 15–23% lower than those measured for NaCl crystals grown form artificial concentrates. In general, the NaCl crystal size distribution was characterized by a narrow dispersion (coefficient of variation within 35–40%).MDC operations were stable over 100 h as a result of a careful control of supersaturation, polarization phenomena, nucleation process and hydrodynamics.
Journal: Separation and Purification Technology - Volume 71, Issue 1, 29 January 2010, Pages 76–82