In the present study, a five‐stage solar still is investigated in which paraffin wax was considered as the phase change material. Considering the climatic conditions of Iran and its locating in an arid area and shortage of freshwater resources, it is essential to produce freshwater from saline water resources. So, herein, a multi‐stage solar still as a commonly used water desalination apparatus with paraffin wax phase change materials was designed, fabricated, and tested. On the back of the collector absorber, the paraffin wax was applied for storing the additional solar energy. The results showed that the application of paraffin‐wax phase‐change agent leads to a 15% increase in freshwater production. The quantity of water generated was also studied in the flow rates of 0.7, 1.3, and 1.8 L/min with and without phase change materials. The results showed that the highest quantity of water produced is obtained in the 1.3 L/min flow rate. Finally, the quantity of water generated in the five stages of the desalination process was separately measured and found that the water produced in the first stage was 70% of the total water.

中文翻译：

---

使用相变材料的多级太阳能蒸馏器的实验研究

在本研究中，研究了一种五阶段的太阳蒸馏器，其中石蜡被认为是相变材料。考虑到伊朗的气候条件及其在干旱地区的位置以及淡水资源的短缺，从盐水中生产淡水至关重要。因此，在本文中，设计，制造和测试了一种多级太阳能蒸馏器，作为一种常用的带有石蜡相变材料的水脱盐设备。在集热吸收器的背面，使用了石蜡来存储额外的太阳能。结果表明，使用石蜡-蜡相变剂可使淡水产量增加15％。在有和没有相变材料的情况下，还以0.7、1.3和1.8 L / min的流速研究了产生的水量。结果表明，以1.3升/分钟的流量可获得最高量的水。最后，分别测量了脱盐过程的五个阶段中产生的水量，发现在第一阶段中产生的水占总水量的70％。