Scaling of reverse osmosis (RO) membrane surface is one of the main problems in desalination proc- esses. To mitigate scales, organic anti-scalants are often used. If the dosages of anti-scalants are reduced, by using...Scaling of reverse osmosis (RO) membrane surface is one of the main problems in desalination proc- esses. To mitigate scales, organic anti-scalants are often used. If the dosages of anti-scalants are reduced, by using other much cheaper scale inhibitors, RO running cost will decrease greatly. The present paper investigated the inhi- bition of CaCO3 precipitation by zinc ions in RO system. The results show that the zinc ion concentration of 2mg?L-1 was able to exert a marked suppression effect on both bulk precipitation of CaCO3 and on membrane scaling on waters of moderate hardness.展开更多
Fouling induction period of CaCO3 on heated surface was studied with the micro video technology. The rates of nucleating and nuclei growing were measured under various experimental conditions. The experimental results...Fouling induction period of CaCO3 on heated surface was studied with the micro video technology. The rates of nucleating and nuclei growing were measured under various experimental conditions. The experimental results showed that both nucleating and nuclei growing rates of CaCO3 increased obviously with surface temperature and concentration of reagents. In addition, the experiment of fouling induction period on the surface material of chemical plated nickel-phosphorus-polytetrafluoroethylene indicated that not only the nucleate rate of CaCO3 decreased but also some fouling particles with certain size were easy to peel off from the heated surface under shearing stress, which means that the property of surface material is one of the most important factors influencing fouling induction periods.展开更多
基金Supported by the National Natural Science Foundation of China (No.20306015) and the Scientific Research Foundation of theState Education Ministry for Returned Overseas Chinese Scholars (No.[2003]406).
文摘Scaling of reverse osmosis (RO) membrane surface is one of the main problems in desalination proc- esses. To mitigate scales, organic anti-scalants are often used. If the dosages of anti-scalants are reduced, by using other much cheaper scale inhibitors, RO running cost will decrease greatly. The present paper investigated the inhi- bition of CaCO3 precipitation by zinc ions in RO system. The results show that the zinc ion concentration of 2mg?L-1 was able to exert a marked suppression effect on both bulk precipitation of CaCO3 and on membrane scaling on waters of moderate hardness.
基金Supported by the National Natural Science Foundation of China.
文摘Fouling induction period of CaCO3 on heated surface was studied with the micro video technology. The rates of nucleating and nuclei growing were measured under various experimental conditions. The experimental results showed that both nucleating and nuclei growing rates of CaCO3 increased obviously with surface temperature and concentration of reagents. In addition, the experiment of fouling induction period on the surface material of chemical plated nickel-phosphorus-polytetrafluoroethylene indicated that not only the nucleate rate of CaCO3 decreased but also some fouling particles with certain size were easy to peel off from the heated surface under shearing stress, which means that the property of surface material is one of the most important factors influencing fouling induction periods.