渣油加氢装置加热炉综合改造分析

Analysis on comprehensive transformation of heating furnace in residue hydrogenation unit

渣油加氢加热炉存在过剩氧含量高,辐射室氧含量波动大,排放烟气NO_(x)浓度高以及加热炉排烟温度高、热效率低等问题。针对以上问题对加热炉系统进行了综合性改造:增设APC(先进过程控制),加热炉负压及氧含量波动明显减小,使得加热炉运行更为稳定;更换低氮燃烧器,排放烟气NO_(x)的质量浓度由80.43 mg/m^(3)降低到24.66 mg/m^(3),远低于国家排放标准(100 mg/m^(3));将热管式空气预热器升级为钢板-铸铁板组合式空气预热器,夏季排烟温度由130℃以上降低到115℃左右,加热炉热效率上升明显。经过一系列的改造,渣油加氢装置加热炉各项运行指标均得到优化,达到了节能环保的改造目的。

The heating furnace of residue hydrogenation unit has the problems, such as high excess oxygen content, large fluctuation of oxygen content in radiation chamber, high concentration of NO_(x)in exhaust gas, high exhaust gas temperature and low thermal efficiency. To solve the above problems, a comprehensive transformation of the heating furnace system is carried out. Adding an advanced process controller, the fluctuation of negative pressure and oxygen content of the heating furnace are significantly reduced, making the operation of the heating furnace more stable. Replacing the low nitrogen burner, the mass concentration of NO_(x)in the discharged flue gas is reduced from 80.43 mg/m^(3)to 24.66 mg/m^(3), which is far lower than the national emission standard(100 mg/m^(3)). Upgrading the heat pipe air preheater to a steel plate and cast iron plate combined air preheater, the flue gas temperature in summer is reduced from more than 130 ℃ to about 115 ℃, and the thermal efficiency of the heating furnace increases significantly. After a series of transformation, the operation indexes of the heating furnace of the residue hydrogenation unit have been greatly improved, and the transformation purpose of energy conservation and environmental protection has been achieved.