Acid dew-point (ADP) is the temperature at which the acid vapor, normally means sulfuric acid (H₂SO₄), in flue gas begins to condense. Acid condensation can result in low-temperature corrosion (LTC), which can threaten the safety of boilers. An exhaust temperature higher than ADP can relieve LTC, however, result in a low thermal efficiency. Therefore, ADP is regarded as a key parameter to guide safety and efficiency of boilers. Previous investigations on ADP are abundant, but a comprehensive review is absent. This work tried to fill this gap. First, the existing methods for ADP determination, including empirical models, semi-empirical models, and measurement methods, were explained. The empirical models were specially classified according to the transformation path of SO₃/H₂SO₄ in flue gas. Then, these methods were compared and evaluated, and the difficulty in identifying the beginning of the acid condensation was considered to result in the different results among varied methods. A new method which can reveal the acid condensing process was recommended for evaluating and discussing the issue of ADP. Moreover, this paper also involved the topic on preventing LTC below ADP focused by the currently popular deep waste heat recovery field. Finally, future research directions were suggested.

酸露点（ADP）是烟气中的酸蒸汽（通常表示硫酸（H ₂ SO ₄））开始冷凝的温度。酸冷凝会导致低温腐蚀（LTC），从而威胁锅炉的安全。排气温度高于ADP可以减轻LTC的负担，但是会导致热效率低。因此，ADP被视为指导锅炉安全性和效率的关键参数。先前对ADP的调查非常丰富，但缺乏全面的审查。这项工作试图填补这一空白。首先，解释了用于确定ADP的现有方法，包括经验模型，半经验模型和测量方法。根据SO ₃的转化路径对经验模型进行了特殊分类。/ H ₂ SO ₄在烟气中。然后，对这些方法进行了比较和评估，认为在识别酸缩合反应的起点方面的困难导致了各种方法之间结果的差异。建议使用一种可以揭示酸冷凝过程的新方法来评估和讨论ADP问题。此外，本文还涉及了以当前流行的深度余热回收领域为重点的防止LTC低于ADP的主题。最后，提出了今后的研究方向。