1) Increased thermal resistance, resulting in an increase in exhaust temperature of the furnace and a decrease in thermal efficiency;

2) Reduced the flow area of smoke, increased the flow velocity of smoke, and increased the resistance of smoke flow;

3) On the low-temperature heating surface at the tail, the accumulated ash on the pipe wall is more likely to adsorb the sulfuric acid vapor contained in the flue gas, exacerbating dew point corrosion.

With the continuous increase in the quantity and proportion of processing high sulfur crude oil, as well as the lack of desulfurization measures for the tower top and low pressure high sulfur gas in the device, self-produced gas will be used as the heating furnace for this device. In addition, adjustments to the production plan of the device and invisible influencing factors will cause the sulfur content of the fuel used in the heating furnace to exceed the standard, Causing severe corrosion and scaling of the heating furnace flue gas in low-temperature areas (convection furnace tubes, air preheater outlet, waste boiler outlet, and induced draft fan); In addition, some heating furnaces that use waste heat recovery operate at low loads, and their exhaust gas temperature is too low. When the sulfur content in the fuel is high, it can also cause severe dew point corrosion. At present, dew point corrosion is the main obstacle to further improving the thermal efficiency of heating furnaces, and this problem is becoming increasingly prominent with the increasing amount and proportion of processed high sulfur crude oil, endangering safety production and directly affecting furnace efficiency.