高温多效蒸馏海水淡化系统阻垢技术研究

Analysis of Antiscaling in High-temperature MED Distillers

提高热法海水淡化技术市场竞争力的关键在于降低制水成本。增大最高蒸发温度可以增加多效蒸馏的运行总温差,提高蒸发器效数和造水比,从而显著降低运行成本。蒸发温度的上升将带来结垢风险的增加。采用动态模拟试验研究了主流热法阻垢剂在高温多效蒸馏海水淡化系统中的阻垢效果。相比空白试验,添加阻垢剂的试验组换热管重量增加显著降低,换热管表面更加光洁且未检测出成垢元素成分,试验后水样中钙、镁离子含量降低值也较小。结果验证了通过化学加药实现高温多效蒸馏方案的可行性。

Reducing water production cost is a key point in thermal seawater desalination system.Since the operation cost is directly related to the Gain Output Ratio(GOR)in Muli Effect Disalination(MED)system,an effective method,in order to reduce water cost,is to rise up Top Brine Temperature(TBT)to increase the temperature range.However,high evaperation temperature means high scaling risk.The main objective of this research is to investigate the properties of current antiscalants in high temperature MED systemn by dynamic simulation tests.Comparing to control test,the heat exchange tubes in experimental tests with antiscalants dosing had less weight increases and more bright and clean sufaces wherein no scaling element was detectived.The decrease of Calcium and Magnesium irons in brine were also less in experimental tests.These results reveal the feasibility of high temperature MED by dosing antiscalants currently used in traditional MED systems.