在供暖、通风和空调系统中，液-气膜能量交换器（LAMES）可以作为传统热交换器的替代品。这是可能的，因为LAMES使用半透膜在空气和液体干燥剂流之间同时传递热量和水分。然而，研究表明，如果离子从干燥剂溶液中沉淀并积聚在膜中，LAME容易受到结晶污染。本文的主要目的是利用三种干燥剂溶液对LAME中的结晶污垢进行敏感性研究。 在室温条件下，使用干燥空气对三种干燥剂溶液进行脱水，即氯化锂（aq）、氯化镁（aq）和氯化钠（aq）。通过分析试验过程中通过膜的水分通量的变化，采用间接方法确定结晶污垢对LAME的影响。此外，在试验后，使用直接法（扫描电子显微镜–SEM）检查膜上是否存在沉积物。结果表明，结晶污染通过降低膜的水分通量对LAME产生负面影响，导致污染率为0。 4-29克（平方米·氢）。研究发现，与平衡相对湿度（ERH）较低的溶液（即NaCl（aq）>MgCl2（aq）>LiCl（aq））相比，平衡相对湿度（ERH）较高的干燥剂溶液会产生更高的污染率。SEM显微照片证实了使用三种干燥剂溶液测试的膜上存在结晶沉积物。此外，在使用具有最高ERH（即NaCl（aq））的干燥剂测试的膜表面上观察到由大立方晶体组成的滤饼层。本文的研究结果对于选择合适的干燥剂溶液，从而最大限度地降低LAMES结晶结垢的风险具有重要的实用价值。 引用:2019年冬季会议，佐治亚州亚特兰大，会议论文

Liquid-to-air membrane energy exchangers (LAMEEs) can serve as alternatives to conventional heat exchangers in heating, ventilating and air-conditioning systems. This is possible because LAMEEs use semi-permeable membranes to simultaneously transfer heat and moisture between air and liquid desiccant streams. However, research has shown that LAMEEs are susceptible to crystallization fouling if ions precipitate from desiccant solutions and accumulate in membranes. The main objective of this paper is to perform a sensitivity study of crystallization fouling in a LAMEE using three desiccant solutions. Experimental tests are performed by using dry air to dehydrate three desiccant solutions, namely LiCl(aq), MgCl2(aq), and NaCl(aq), at room temperature conditions. An indirect method is used to determine the impact of crystallization fouling on the LAMEE by analyzing the changes in moisture flux through the membrane during a test. In addition, a direct method (scanning electron microscopy – SEM) is used to examine the presence of deposits on membranes after a test. The results show that crystallization fouling negatively impacts the LAMEE by reducing the moisture flux through the membrane, and resulting in a fouling rate of 0.4 – 29 g/(m2·h2). A desiccant solution with a higher equilibrium relative humidity (ERH) is found to produce a higher fouling rate compared to a solution with lower ERH, i.e. NaCl(aq) > MgCl2(aq) > LiCl(aq). SEM micrographs confirm the presence of crystal deposits on the membranes tested using the three desiccant solutions. Furthermore, a cake layer which consists of large cubic crystals is observed on the surface of the membrane tested using the desiccant with the highest ERH (i.e., NaCl(aq)). The findings of the paper have significant practical value with regards to the selection of suitable desiccant solutions that can minimize the risk of crystallization fouling in LAMEEs.