We are in the process of building a new vacuum crude heater using current design considerations — a twin-cell radiant section with horizontal tubes and a conservative design heat flux rate. We expect that the heater will need to be decoked no more often than once every three years. We are considering NOT installing a steam-air decoking effluent line and relying just on pig decoking to clean the ID of the tubes (we have included removable spools to facilitate the pig decoking). We have heard that others apparently rely on pig decoking exclusively for heaters that are in both moderate AND severe coking applications. We have also heard that some others apparently alternate between pig decoking and steam-air decoking on subsequent turnarounds for these same types of heaters. We would appreciate any comments from forum members to assist us in our decision-making. Thanks for your cooperation!
Welcome to the forum.
In my opinion it is good to have the steam-air decoking capability. This way you can decoke the heater without having to call an outside contractor to pig it. Depending of the location, it can take several weeks to get the pigging contractor to site. If you have an unplanned shutdown in the plant, you have the option to steam-air decoke the heater.
The link below can be helpful:
Mr. CG, this post refers to a vacuum heater, if you are smart, you plan way in advance your decoking window, steam air is always a good option for vacuum heaters.
You must be logged in to reply to this topic.