Is it necessary to fill the roof of a methanol floating roof tank with nitrogen for sealing?
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Is it necessary to fill the roof of a methanol floating roof tank with nitrogen for sealing? At present, the small methanol storage tanks in the intermediate tank area of our facility are all ordinary tanks, equipped with breather valves and self-acting control valves for nitrogen at the top. The 10,000-ton finished methanol storage tank is of the internal floating roof type; no nitrogen is filled above the floating roof of the tank, and there are vent windows on the sides of the tank’s top, with no inerting measures such as nitrogen filling in place. I wonder, dear colleagues from HaiChuan, whether your units’ methanol floating roof storage tanks are equipped with sealed nitrogen, and if there are any relevant design specifications regarding this. Additionally, is it necessary to install a spray system on the methanol storage tank? Only high-pressure fire pumps have been installed around our tanks; do your systems also include spray systems or just fire pumps?
A nitrogen seal with a slight positive pressure is required to reduce evaporation losses of the medium. Spraying water is used for cooling at high temperatures; the choice depends on the properties of the medium. Generally, it is necessary to have this in place during safety inspections
Do floating roof tanks also need to be added? The entire tank has a diameter of 30 meters; there are ventilation holes at the top of the cylinder, but no exhaust valve. Several nitrogen supply lines are required, and a certain amount of nitrogen is needed to achieve a proper nitrogen seal. Who has a ready-made sketch to share?
This post was last edited by TH373637 on 2015-8-2 at 19:12. The internal floating roof should be chosen based on the properties of the medium being stored; it is generally installed to prevent evaporation losses. Your tanks are not very large, around 10,000 m³ in capacity, with normal storage volumes below 8,000 m³. One nitrogen supply line is sufficient for operation under slightly positive pressure, resulting in minimal losses. Proper tank farm designs include such features, especially in petrochemical systems, where they have been used for a long time
It is necessary to install a spray system; in summer, when temperatures are high, the temperature inside the tank can reach 60 degrees
There is no need to install a nitrogen seal; internal floating roof tanks are not sealed vessels, so a nitrogen seal serves no purpose.
Listen to the person above about the nitrogen sealing issue! Spray water is not necessary for methanol finished product storage tanks, unless you are near the equator
The current inquiry is whether some manufacturers have nitrogen systems in place, while others do not have such designs. Our unit was designed in 2004–2005; I wonder whether the methanol storage tanks in newly built units are equipped with nitrogen sealing, and whether the safety standards for design have improved nowadays
It has a nitrogen seal and a spray system; I heard that it’s used to cool down in case of a fire. Please let those who know more correct me if I’m wrong
Spray water for dilution and cooling – Spray water does not refer to that used for cooling in high-temperature conditions
Turning on the water while it’s on fire – not afraid it will catch fire even more