Coking in tubular heating furnace
Thread Content
How exactly does charring occur in tubular heating furnaces, and what are the key operational points?
I’m not quite clear about the poster’s description; does the poster mean that everyone should analyze the reasons for coking in a tubular furnace during operation and the key points for dealing with it? Or does it refer to some other issue?
It’s about the process of burning and the precautions to take. Since I’ve never experienced burning before, I’d like to know the specifics of the process
I’m also very interested in knowing the process of burning out in a heating furnace: including 1) what kind of burning process is used, is it nitrogen + air? Should we still use the steam + air method? 2) What are the requirements for the temperature rise curve during the burning process? To what degree of charring? 3) Are there also preparatory work before burning and post-burning processing?
Many literature sources were found, mainly focusing on online coking in coke ovens, all of which employ a steam + air coking method. Can nitrogen + air be used? I would appreciate some advice from those who are more experienced.
The medium inside the heating furnace tubes is heavy crude materials such as crude oil and residue, which tend to coking. Heating furnaces in refineries, particularly those used in atmospheric and vacuum distillation units as well as coking plants, are prone to coking. When coking occurs, air is used primarily for burning, while steam is used to lower the temperature of the furnace tube walls, thereby preventing overheating and damage to the tubes； At present, burning is no longer recommended in China; firstly, it wastes fuel, and secondly, it causes certain damage to the furnace tubes ； Currently, domestic petrochemical refineries have begun to use mechanical coke cleaning for furnace tubes, which provides thorough cleaning with minimal damage to the furnace tubes.
What is the mechanical coking removal method? Should high-pressure water guns be used for coking removal, or should chemical additives be employed? Could you explain it in detail?
Hydraulic force is used to drive the coke-clearing balls to move inside the furnace tubes, thereby removing the coke from the inner walls of these tubes. At present, China does not possess the technology to produce such coke-clearing balls, so they have to be imported from abroad
Mechanical coking removal has been used multiple times in our company; the technology is of American origin. The company is a joint venture between Shanghai and Luoyang, and it delivers excellent results with short processing times and safe operation.
The coking inside the furnace tubes can sometimes be very hard. What is the structure of a coking removal ball, and how can it remove such hard coke?
I’m facing the same problem here; I’d like to know about the burning curve of the heating furnace, the relationship between air, steam, and temperature, and related information