余热锅炉省煤器防泄漏研究

发布时间：2018-05-19 08:07

  本文选题：省煤器 + 泄漏　； 参考：《西安石油大学》2016年硕士论文

【摘要】：余热锅炉为催化裂化配套装置,是炼油厂重要的节能设备,省煤器是利用余热锅炉尾部的热烟气来加热给水的热交换器。如果省煤器发生泄漏,将降低回收烟气余热的能力,同时由于频繁修理更换,造成了人力物力的大量浪费,大大降低了余热锅炉运行效率,甚至威胁到装置的正常运行。本文针对某石化企业省煤器的泄漏问题开展研究工作,并针对这些泄漏的原因采取必要的设备和技术改造,最终取得显著的效果。研究结果表明:由于省煤器入口水温低于烟气露点,造成烟气中的酸酐与水蒸气凝结在管道外壁,对外壁形成低温硫腐蚀。这是该余热锅炉省煤器泄漏的主要原因。除氧器的异常工作造成余热锅炉给水氧含量超标,从而引起省煤器管道内壁氧腐蚀减薄。这对于该余热锅炉省煤器的泄漏起辅助性促进作用。更换尾部受热面、增加换热器模块等改造措施,可以将烟气经高温省煤器出入口温差增加9.04℃;将经低温省煤器前后温差增大29.59℃;将余热炉排烟温度降低87.46℃。给水预热器的使用,将除氧水经省煤器后温度提高39.62℃,达到144℃,高于余热锅炉的低温露点腐蚀温度。用ND钢取代原来的20G钢,提高了余热锅炉省煤器的抗腐蚀性能。余热锅炉实施改造后,近一年来运行良好,再没有出现泄漏的情况,改造效果显著。这为以后解决类似问题提供思路和参考价值。
[Abstract]:The waste heat boiler is an important equipment for energy saving in the refinery, and the waste heat boiler is a heat exchanger which uses the hot flue gas from the tail of the waste heat boiler to heat the feed water. If the economizer leaks, it will reduce the capacity of recovering the waste heat of flue gas, at the same time, because of frequent repair and replacement, it will cause a large amount of waste of manpower and material resources, greatly reduce the operation efficiency of the waste heat boiler, and even threaten the normal operation of the device. In this paper, the leakage problem of economizer in a petrochemical enterprise is studied, and the necessary equipment and technical renovation are adopted for the reasons of these leakage, and finally remarkable results are obtained. The results show that because the inlet water temperature of economizer is lower than the dew point of flue gas, the anhydride and water vapor in the flue gas condenses on the outer wall of the pipeline and the external wall forms low temperature sulfur corrosion. This is the main reason for the leakage of the economizer of the waste heat boiler. Abnormal operation of deaerator results in excess oxygen content in feedwater of waste heat boiler, which causes oxygen corrosion thinning in the inner wall of economizer pipeline. This helps to promote the leakage of the economizer of the waste heat boiler. By replacing the rear heating surface and increasing the heat exchanger module, the flue gas temperature difference can be increased by 9.04 鈩，

本文编号：1909349