Why does the bulky tubular furnace keep leaking internally?
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The tubular furnace in the rough processing section of my chemical production workshop has been experiencing internal leaks frequently since its major repair; every time it is repaired, leaks occur again within a few days, on average once every 2 days. I don’t know why; Haiyou, please help
Your explanation isn’t very clear. What do you mean by internal leakage in a tubular furnace? Is the furnace tube burned through?
Leakage in the tubular furnace? This has also happened to me: after disassembling the tubular furnace, inspection revealed that the leakage was caused by severe corrosion at the first elbow at the bottom of the radiation section. Work was halted for repairs, and all the 180-degree elbows in the lower part of the radiation section were replaced. After those replacements, it was found that only the first elbow still had severe frictional corrosion resulting in leakage.
What material is the furnace tube made of? Do you use washed ammonia or steam ammonia? Process parameters must be strictly controlled; the presence of water in the oil-rich stream is strictly prohibited, based on the temperature of the radiation section and the convection section of the tubular furnace at the oil-rich temperature.
Generally, the oil content is high and the water content is high; the processes prior to crude processing, desulfurization, and ammonium sulfate production are not carried out properly
Check whether the ammonia content in the gas after passing through the saturator exceeds the limit. It is recommended to replace the furnace tube material with SUS304 or 1Cr5Mo
Agree with the above view. Check the effectiveness of the previous processing steps, improve the benzene washing process, strictly prevent water from entering the oil washing process, and replace components with corrosion-resistant materials.
Our unit uses boiler steel grade 20; leaks occur in the radiation section due to the insulation material in the chimney falling off and blocking it. The sulfides present in the gas are absorbed by the insulation material, resulting in the formation of acidic substances that corrode the furnace tubes and cause oil leakage. The oil leakage in our pipes is caused by external corrosion.
I agree with what was said on floor 5: if the oil is too rich in water, cavitation can occur in the pipes at high temperatures.
1. The desulfurization and deammonification effects are poor; the preparatory work before the benzene elution process is not carried out properly. Some plants even lack an ammonium sulfate production process, which results in ammonia from the gas entering the washing oil during benzene elution, causing severe corrosion in the high-temperature tubular furnaces and leading to leaks. 2. The temperature control in the tubular furnace is poor, fluctuating frequently, which leads to localized thermal stress corrosion ；
It is likely that the oil used for washing contains a high level of water; as it enters the benzene washing tower, it absorbs some of the acidic gases present in the gas, thereby forming acids. The high temperature inside the tubular furnace indirectly increases the intensity of corrosion, which over time leads to corrosion and leakage.