Where does the air displaced by the commissioning of the spherical tank go?
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When a spherical tank is overhauled and put back into service, it is generally purged with an inert gas to ensure that the oxygen content is within acceptable levels. I would like to ask my colleagues: when purging the air from inside the spherical tank, does that air go into the flare system or is it released directly into the atmosphere?
One must absolutely not enter the flare tower on the first attempt, as the oxygen content is usually quite high at that time, and entering the flare system poses a potential safety risk. Subsequent displacement can either be vented to the atmosphere or sent to a flare stack. However, it is important to note that venting to the atmosphere poses a risk of creating a nitrogen-rich environment; therefore, careful selection of the discharge outlet is necessary, and safety measures must be implemented at that outlet to prevent operators or unauthorized persons from entering and suffering suffocation ； When arranging the flare, attention must be paid to the emission volume; if too much nitrogen is emitted, it may cause the flare to go out.
Some materials with dew point requirements cannot be displaced using water
I think the opinion on the second floor is correct.
Entering the atmosphere is relatively safe; the vent pipeline should be placed at a higher height! Prevent operator poisoning!
Direct emission into the atmosphere. :lol
Delving deeper, assume that the oxygen content in the spherical tank before the first displacement is 20%. Typically, nitrogen is introduced until the gauge pressure reaches 4 KGF, after which the pressure is reduced to 0 gauge pressure. By the time the pressure reaches 4 KGF due to the nitrogen filling, the oxygen content in the tank has actually dropped to around 4%. Since the other gas present is nitrogen, and considering nitrogen’s significant explosion-suppressing effect, is there any problem with sending this mixture to the flare?
For the spherical tanks that were put into operation at the beginning of this year, air replacement can be done by simply venting it. Cannot enter the torch. There are various replacement methods; some of those mentioned above don’t really address the issue at hand. Is water necessarily the best option? What to do about starting operations in the north during winter?
1. Replace with water, and the gas inside the tank is directly released into the atmosphere. However, water replacement is limited by geographical factors; since temperatures are very low in the north during winter, water replacement cannot be carried out at that time. 2. Replace with nitrogen, and discharge the gas inside the tank directly into the atmosphere. (The top of the spherical tank is equipped with a square opening; the \"Code for Fire Protection Design of Petrochemical Enterprises\" requires it to be 3 meters above the platform.) Therefore, with a little attention from the staff, no danger should arise.
1. Pressurize with water. 2. Replace the discharged precipitation with nitrogen gas. 3. Nitrogen purging sampling is satisfactory. ok