Raman spectroscopy for real-time concurrent detection of multiple scalants on RO membranes
Raman spectroscopy for real-time concurrent detection of multiple scalants on RO membranes
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DOI：
10.1016/j.desal.2023.116851
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发表时间：
2023-07
期刊：
影响因子：
9.9
通讯作者：
Danielle J. Park;O. Supekar;V. Bright;A. Greenberg;J. Gopinath
中科院分区：
文献类型：
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作者：
Danielle J. Park;O. Supekar;V. Bright;A. Greenberg;J. Gopinath
反渗透(RO)海水淡化系统的现场监测技术，特别是那些具有化学传感能力的技术，可以为更好地了解重要的结垢机理以及早期发现结垢提供手段。在这项工作中，利用拉曼光谱同时检测反渗透膜上的硫酸钙和碳酸钙结垢，以提供唯一的化学指纹。采用了两种不同的采样方法(手动和自动)，通过比较拉曼检测时间和并发的通量衰减值来评估它们的性能。人工采样策略的结果是，在平均渗透通量下降13%±10%和22%±53%的情况下，检测到了硫酸钙和碳酸钙。自动采样策略提供了更好的性能，检测到的硫酸钙和碳酸钙的平均通量下降分别为8%±35%和4%±53%。自动抽样战略的敏感性增加和变异性减少，为选择优化的抽样战略提供了宝贵的初步见解。能够识别不同结垢晶体的化学成分，包括它们的晶型，是更好地了解用于海水和咸水反渗透淡化的多组分进料流的结晶途径的重要一步。
In-situ monitoring techniques of reverse osmosis (RO) desalination systems, particularly those with chemical sensing capabilities, can provide the means for better understanding important scaling mechanisms as well as early scaling detection. In this work, both calcium sulfate and calcium carbonate scaling on RO membranes were detected concurrently in real time using Raman spectroscopy to provide a unique chemical fingerprint. Two different sampling methodologies (manual and automated) were employed, and their performance was evaluated by comparing the Raman detection times to concurrent values of flux decline. The manual sampling strategy resulted in the detection of calcium sulfate and calcium carbonate at mean permeate flux declines of 13 ± 10 % and 22 ± 3 %, respectively. The automated sampling strategy provided better performance, with detection of calcium sulfate and calcium carbonate at mean flux declines of 8 ± 5 % and 4 ± 3 %, respectively. The increased sensitivity and decreased variability of the automated sampling strategy provided valuable preliminary insights for the selection of optimized sampling strategies. The ability to identify the chemical composition of different scaling crystals including their polymorphs is an important step toward better understanding of the crystallization pathways of multi-component feed streams used in seawater and brackish water RO desalination.