Desalination by batch reverse osmosis (RO) of brackish groundwater containing sparingly soluble salts
Desalination by batch reverse osmosis (RO) of brackish groundwater containing sparingly soluble salts
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DOI：
10.1016/j.desal.2023.116875
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发表时间：
2023-08-12
期刊：
影响因子：
9.9
通讯作者：
Davies，Philip A.
中科院分区：
文献类型：
--
作者：
Hosseinipour，Ebrahim;Harris，Ellie;Davies，Philip A.
间歇式反渗透海水淡化是一种高回收率、高能效的海水淡化新方法。然而，到目前为止，间歇式反渗透主要是用纯氯化钠溶液进行测试。间歇式反渗透的一个重要应用是咸水地下水的淡化，除氯化钠外，咸水中还含有少量的可溶盐。在间歇式反渗透系统的实验研究中，我们使用了模拟地下水(总溶解固体含量从1180到3637 mg/L)，遵循了从埃及和印度的一个地点采集的样品的成分。地下水中的盐分含量很高，可能会导致反渗透膜表面结垢。例如，方解石在盐水中的朗格利埃饱和指数(LSI)达到2.6。尽管如此，该系统在整个100亿小时的运营中都拒绝按比例扩展。实验前后的测试表明，膜的通透性几乎保持不变。诱导时间计算表明，盐度循环不能完全解释阻垢作用。其他防垢机制--如定期冲洗、渗透反冲洗和进料流逆转--也可能起到作用。在回收率0.8时，水力比能耗(SEC)为0.5kWh/m~3，接近等渗透压下氯化钠溶液的水力比能耗。
Batch RO desalination is a new approach to high-recovery, energy-efficient desalination. So far, however, batch RO has been tested mostly with pure sodium chloride solutions. An important application of batch RO is desalination of brackish groundwater which, besides sodium chloride, contains sparingly soluble salts. In this experimental study of a batch RO system, we used simulated groundwater (with total dissolved solids ranging from 1180 to 3637 mg/L) following compositions of samples taken from a location in Egypt and a location in India. The groundwater contained high levels of salts which could be expected to cause scaling on the RO membrane surface. For example, the Langelier Saturation Index (LSI) for calcite reached 2.6 in the brine. Nonetheless, the system resisted scaling throughout >100 h of operation. Membrane permeability remained almost unchanged, as demonstrated by tests conducted before and after the experiments. Induction time calculations showed that salinity cycling did not fully explain the scaling inhibition. Other anti-scaling mechanisms – such as periodic flushing, osmotic backwash, and feed flow reversal – were also likely contributors. At recovery of 0.8, hydraulic specific energy consumption (SEC) was <0.5 kWh/m3and close to that obtained with sodium chloride solution at equivalent osmotic pressure.