Fouling of heat exchangers in energy and power plant industry, oil and gas industry, pharmaceutical and food process industry, industrial waste heat recovery is a major problem which needs to be solved urgently. In the United Arab Emirates, a majority of oil & gas processing plants are located in the desert where water accessibility is limited, thus fin-fan type of heat exchangers are used for cooling and/or heating applications. Such harsh environments cause external fouling which becomes an unavoidable problem in these heat exchangers. With increased humidity and high process temperatures, the dust particulates start to stick on the outer surface of heat exchangers which drastically reduces the thermal performance and increases power consumption. In order to identify possible methods to control and/or eliminate such kinds of external fouling, it is important to identify the composition and morphology of such foulants. This study presents the characterization of selected fouling samples collected from several fin-fan type air cooled heat exchangers taken from a gas processing plant. Scanning electron microscope (SEM) tests were carried out to determine the physical characteristics of sample foulant. Variability in sizes and shapes was found between samples due, perhaps, to different working temperature ranges of the selected heat exchangers. X-ray diffraction (XRD) analyses revealed presence of quartz, calcite, and alumina with traces of halite and hematite. Laser flash analysis (LFA) was conducted to quantify the specific heat capacity, thermal diffusivity and thermal conductivity of the fouling samples. The diversity of these fouling samples reflects complexity with respect to their potential removal and effects on heat transfer characteristics. Though, this research work is a case study for a specific petrochemical plant, however, findings in this study can be adopted by other industries involved in similar chemical processing in the Middle East as well as other countries having similar weather and geological conditions.

能源和发电厂，油气工​​业，制药和食品加工工业，工业废热回收中的热交换器结垢是一个亟待解决的重大问题。在阿拉伯联合酋长国，大部分石油和天然气加工厂都位于沙漠中，那里的水难以获取，因此，鳍片式热交换器用于制冷和/或供热应用。这种恶劣的环境导致外部结垢，这在这些热交换器中成为不可避免的问题。随着湿度增加和过程温度升高，灰尘颗粒开始粘附在热交换器的外表面上，这极大地降低了热性能并增加了功耗。为了确定控制和/或消除此类外部污垢的可能方法，确定这类污垢的组成和形态非常重要。这项研究提出了从几个加气扇式空气冷却换热器收集的选定结垢样品的特性，这些换热器取自天然气加工厂。进行扫描电子显微镜（SEM）测试以确定样品污垢的物理特性。发现样品之间的尺寸和形状存在差异，这可能是由于所选热交换器的工作温度范围不同所致。X射线衍射（XRD）分析表明存在石英，方解石和氧化铝，并带有痕量的岩盐和赤铁矿。进行了激光闪光分析（LFA）以量化结垢样品的比热容，热扩散率和热导率。这些结垢样品的多样性反映了其潜在去除和传热特性影响的复杂性。虽然，这项研究工作是针对特定石化厂的案例研究，但是，这项研究的结果可以被涉及中东类似化学加工的其他行业以及具有类似天气和地质条件的其他国家采用。