What is the required oxygen content for the purging of methanol and dimethyl ether storage tanks or pipelines?
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What is the required oxygen content for the purging of methanol and dimethyl ether storage tanks or pipelines? Last edited by bht11 on 2007-6-25 07:02]
Is it sufficient to avoid reaching the explosive limits of methanol and dimethyl ether?
That is the hydrogen displacement standard, right? Since the explosion limits of methanol and dimethyl ether are not as wide as those of hydrogen, our company initially set the minimum threshold for working with flammable gases at 5%, but for safety reasons, it was finally set at 2%
It is sufficient to be below the lower limit of the explosion limit. Of course, for safety reasons, factories set a larger margin to avoid accidents caused by factors such as incomplete or uneven replacement within the pipes, as well as deviations in the analysis parameters. :handshake
Agreement to have the military rule the world is generally less than 0.5%
From a safety perspective, the lower the oxygen content, the safer it is. However, considering economic costs, if our company needs to replace two 10,000-cubic-meter methanol storage tanks – which are pressure vessels at normal pressure – and the oxygen level is required to be below 0.5%, the cost of nitrogen required will exceed 100,000 yuan. So, on the premise of putting safety first, saving money is also very important: handshake
Process pipelines are to be purged with inert gases such as nitrogen, but I haven’t heard that methanol storage tanks need to be purged with inert gases. Methanol storage tanks are generally atmospheric pressure tanks; if they have a fixed roof, this roof is connected to the atmosphere through flame arresters and vent valves, which allows a certain amount of air to be present inside the tank. Dimethyl ether needs to be stored under pressure, so it must be purged, usually to below 50% of its explosive limit.
There are two purposes for replacement: one is for maintenance, and the other is for production. When preparing for maintenance, it is CO+H2
Nitrogen displacement is generally used to keep the oxygen concentration below 0.5%.
Methanol storage tanks are usually maintained at a slight positive nitrogen pressure, with gas continuously being released through the breather valve. Last edited by Seeing flowers through the mist on 2007-10-7 13:38.]