How often does the coking need to be removed from the delayed coking cycle oil filter after it is put into use? Is there any other good solution?
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Does our unit have to clean the oil filter of carbon deposits every few days? How often does the delayed coking cycle oil filter, which is used by everyone, need to have its coke removed after each time it is put into operation? Are there any other good ways to extend it?
Why so often? When do we stop operations and when do we carry out cleaning? Sometimes it takes several months before cleaning is done. It seems that there’s a lot of coke in your distillation tower as well. To improve the situation, we need to address the issue at its source – namely, why there is so much coke powder in the distillation tower. Let’s see if there are any problems with the operation of the coke tower This won’t work; cleaning must be done using a dual-track approach. If the circulating oil pump can no longer deliver enough flow, it will be problematic, and this issue needs to be resolved as soon as possible.
Reply to 1# xuepeng: When operating, be careful to keep the linear speed of the coke tower at a moderate level, control the temperature at the bottom of the distillation tower properly, avoid exceeding the processing capacity too much, and prevent large fluctuations in system pressure. Generally, cleaning the system once a month is sufficient if operations are carried out properly； The best approach for this filter at present is to use two units in parallel and increase their capacity appropriately
Reply to 3# linweihua6: We also have two units, and sometimes we clean the coke in both of them at the same time. Is there any standard for the steam velocity in the coke tower? We haven’t measured it; could you please advise us?
Reply to 2# Dongfang Zhi Dong: Yes, are there any particular things to be careful about when operating your coke towers? We operate them in a normal manner; sometimes, adjusting the vent water pressure can result in values around 2–2.5. Coking occurs quite severely at the bottom of our distillation towers, and during maintenance, those areas are full of coke
Reply to 4# xuepeng: The gas linear velocity in the coke tower is generally 1.2–1.6 meters per second; it should not exceed 2
Without shutting down the operation currently, it is possible to adjust the operating parameters first to see if there is any improvement: increase the circulation ratio, appropriately reduce the temperatures in the coke tower and the distillation tower, and if possible, increase the pressure in the coke tower. Additionally, it might be useful to switch the feed oil to examine whether the properties of the feed oil are the issue.
Reply to 6# linweihua6: How is the linear velocity determined? Are there any relevant materials? Thank you