The present study investigated the applicability of direct contact membrane distillation (DCMD) in the treatment of a reverse osmosis concentrate (ROC) from petrochemical wastewater. Three commercial flat sheet membranes made of polyethylene or polytetrafluoroethylene, having different contact angles, pore sizes, porosities, and thicknesses, were supplied by Aquastill with the following membrane designation: Standard, Oleophobic and Teflon. Firstly, the different DCMD membranes were characterised in experiments with deionised water. Then, tests with ROC, with a temperature setting to 60 °C in the feed and 20 °C on the distillate side, were performed in full recirculation mode (along 250 h operating time) and in concentration mode (along 72 h operating time, achieving volumetric concentration factors around 10). The DCMD performance, in terms of flux and quality of the distillate, was evaluated during all experiments under different operating conditions. After obtaining the results, all membranes satisfactorily achieved a final water recovery ratio close to 90 %, as well as high rejection factors (above 99.5 %) for all parameters analysed. They also produced high quality water with low electrical conductivity (around 2–7 μS cm^–1). All conditions met the requirements for water reuse in the petrochemical sector. In this case, to treat wastewater with the tested characteristics, the oleophobic membrane from Aquastill presented better efficiency, with a minimum water vapour flux reduction and a water recovery ratio of 90 %.

本研究调查了直接接触膜蒸馏（DCMD）在处理石油化工废水中的反渗透浓缩液（ROC）中的适用性。Aquastill提供了三种由聚乙烯或聚四氟乙烯制成的商业平板薄膜，它们具有不同的接触角，孔径，孔隙率和厚度，膜名称如下：标准，疏油和特氟隆。首先，在去离子水实验中表征了不同的DCMD膜。然后，在完全再循环模式（沿着250小时的运行时间）和浓缩模式（沿着72小时的运行时间，在进料中将温度设置为60°C，在馏出物侧将温度设置为20°C）下进行ROC测试。达到约10的体积集中系数。DCMD性能 在所有实验中，在不同的操作条件下，对馏分的通量和质量进行了评估。获得结果后，所有膜均令人满意地实现了接近90％的最终水回收率，以及所有分析参数的高截留率（高于99.5％）。他们还生产出电导率低（约2–7μScm的高质量水）^–1）。所有条件均满足石化行业中水回用的要求。在这种情况下，为了处理具有测试特性的废水，Aquastill的疏油膜表现出更高的效率，水蒸气通量减少最少，水回收率达到90％。