催化裂化装置余热锅炉受热面积灰的处理方法及评价

Treatment measures and effect evaluation of heating surface deposition of waste heat boiler in FCC unit

采用不同方法对重油催化裂化装置余热锅炉的受热面积灰进行了清洗。借助Petro-SIM v3.3软件,对余热锅炉后取热系统进行了模拟,并对不同方法的清洗效果进行了评价。结果表明:采用不同的清洗方法,排烟温度均降低,锅炉总取热量均增加;在水保护段,采用水喷淋清洗法(方法 1)的脱灰效率低于大颗粒催化剂清洗法[包括部分烟气进入烟囱(方法 2)和全部烟气进入烟气脱硫装置(方法3)];在蒸发段,方法 2和方法 3的脱灰效率降低,尤其是方法 3;在省煤段,方法 1的总传热系数变化率为91.84%,脱灰效果最好。无论从排烟温度的下降,热负荷的提升,还是总传热系数的变化率来看,方法 1是最高效的。

The ash deposition on the heating surface of waste heat boiler in a catalytic cracking unit was cleaned by different methods. The heat recovery system of waste heat boiler was simulated by the Petro- SIM v 3. 3 software,and the cleaning effect of different methods was evaluated. The results showed that the different methods were adopted so that the exhaust gas temperature decreased and boiler heat extraction increased. In the water protection section,the ash removal efficiency of the water spray cleaning method（ method 1） was lower than that of the catalyst pellet cleaning method[including part of flue gas into the chimney（ method 2） and all of it into the flue gas desulfurization unit（ method 3） ].In the evaporation section,the ash removal efficiencies of method 2 and method 3 were lower,especially the latter. In the province coal section,the variation rate of total heat transfer coefficient of method 1 was91. 84% and the deashing effect was the best. The method 1 was the most efficient in terms of declining of exhaust gas temperature,increasing of heat load and changing rate of total heat transfer coefficient.