Abstract: As a special type of furnace，the natural gas heater adopts the indirect heating by the heat-transfer medium. Apparently，the properties of the heat-transfer medium and the form of heat transfer process of the heat-transfer medium in the cylinder are the key elements that greatly affect the thermal efficiency of natural gas heater. Analysis and comparison of the temperature distribution and flow condition between the water and ethylene glycol in the cylinder were carried out by experimental investigations. Based on the investigations on medium selection and heater’s integral structure and combining with the engineering practical needs，effective measures to improve the efficiency of natural gas heaters have been brought forward in this article and the technology has got itself the China invention patents．

Key words: natural gas heater, heat-transfer medium, ethylene glycol, experimental system

摘要： 天然气加热炉是采用中间载热介质间接加热的一种特殊的炉型形式，中间载热介质的性质及其传热过程的形成是影响天然气加热炉效率的重要关键因素。本文通过天然气加热炉试验系统对大筒体内水和乙二醇两种不同中间载热介质的温度分布和热流场进行了分析比较，研究不同中间载热介质对天然气加热炉换热的影响，并结合工程实际的需要，从中间载热介质的选择和加热炉整体传热结构两方面，提出了改善天然气加热炉效率的有效途径，并获得了国家发明专利授权。

关键词: 天然气加热炉, 载热介质, 乙二醇, 试验系统