Determination of operating pressure and design pressure for tank renovation work
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We have a project to renovate a storage tank. The medium stored in this tank is refined oil; its volume is 7000 m³, and it is of the internal floating roof type. Due to the evaporation of gasoline inside the tank, it is necessary to convert it into an internal floating roof tank equipped with a nitrogen seal system, with the set pressure for the nitrogen seal valve being 500 Pa. Could everyone help me check whether the operational parameters and design parameters after the modification are correct? First, thank you all. Purpose, Medium, Tank Type, Operating Internal Positive Pressure Pag, Operating External Pressure Pag, Design Positive Pressure Pag, Design Negative Pressure Pag. Before modification: Diesel, internal floating roof, atmospheric pressure, 0, 1300, 490. After modification: Gasoline, internal floating roof with nitrogen sealing, 500, 0, 1300, 490
The operating and design parameters of the modified storage tank appear to be reasonably set. The operating internal pressure is increased to 500 Pa due to the inclusion of a nitrogen sealing system, which effectively prevents gasoline from evaporating, reduces the amount of oxygen in the space, and lowers the risk of explosion. The design positive and negative pressures remain unchanged, in line with the design standards for conventional internal floating roof storage tanks. Ensure that the nitrogen pressure setting is compatible with the tank design to prevent excessive pressure from damaging the tank structure. Overall, the renovation plan seems appropriate. .
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1. All design conditions related to computation remain unchanged； 2. The properties of the medium have remained essentially unchanged ； 3. However, since it has been modified into a storage tank with a nitrogen seal, corresponding facilities such as nitrogen valves, pipelines, and VOC collection and emission outlets should be added to the tank top as well
Thank you for your reply. The design pressure and temperature of the storage tank remain unchanged; the tank top needs to be modified to add 5 connection ports ； The specifications of the original wind-resistant ring on the tank wall need to be increased. The unanchored tank was converted into an anchored tank, with 30 anchoring bolts added to the tank bottom.
Thank you for your reply! You are absolutely right! The design conditions and media related to calculation remain unchanged; the internal floating roof tank has been replaced with an internal floating roof nitrogen-sealed storage tank, the operating pressure has increased, and corresponding modifications are required for both the tank top and the tank walls. The 10 ventilation holes on the top of the tank need to be sealed.
Thank you very much for your discussion and reply! When the internal pressure was changed from atmospheric pressure to 0.5 KPa, structural calculations were performed on the storage tank again, and it was found that the specifications of the original intermediate reinforcement ring had increased. Additionally, the tank was originally a \"non-anchored tank,\" but after the increase in internal pressure, it became an \"anchored tank.\"
Atmospheric pressure storage tanks are not within the scope of regulation, so there is no need to pay too much attention to them.