海水淡化中的pH在线检测技术综述

Review of on-line pH measuring technology in seawater desalination

pH是保障海水淡化系统正常运行和水质是否合格的重要指标,pH在线检测技术主要有电化学法和分光光度法。在海水淡化中主要应用基于pH玻璃电极的电化学法,但存在电极污染、干扰、腐蚀、维护等问题。为解决上述问题,总结了电极自清洗、抗干扰、防腐蚀、在线维护等措施,提高了pH测量的稳定性和可靠性。讨论了海水淡化中pH在线检测新技术:基于pH-ISFET的电化学法和基于光纤pH传感器的分光光度法。并展望了海水淡化中pH在线检测技术的发展趋势。

pH value is an important parameter in seawater desalination. It ensures operation stability and water quality in the desalination system. Electrochemical method and spectrophotometry are the two main methods of on-line pH measurement. The normal method of the on-line pH measurement is electrochemical method based on pH glass electrode. The problems of pH glass electrode in the industry application, such as fouling, interference, corrosion and maintenance were analyzed. The solutions such as auto-cleaning, anti-interference, anti-corrosion and on-line maintenance were summarized. The stability and reliability of pH measurement were improved by these solutions. The two new on-line pH measuring technology was put forward, one was pH-ISFET based on electrochemical method, the other was optical fiber pH sensor based on spectrophotometry. The development trend of on-line pH measurement in seawater desalination was prospected.