Regarding the vacuum level after accidental emission of high-temperature gases from the torch
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Regarding the situation after an accidental release of high-temperature gas from the torch, as the system pipes cool down, part of the fluid within those pipes condenses, resulting in a vacuum in the system. What is the maximum possible level of vacuum that can occur? I seek the advice of experts in torch design; please share your knowledge generously. :handshake :handshake
Nitrogen is taken into account in the design; when the temperature drops at the end of discharge and the pressure is low, a valve opens automatically to introduce a combustible gas or nitrogen, maintaining a slight positive pressure.
Thank you so much! It’s a pretty good measure. Another possibility is that, under accident conditions, neither the fuel gas nor nitrogen can be supplied in a timely manner. The current design of the torch water seal allows for a maximum vacuum level of 3 meters of water column, but I am concerned about whether a complete vacuum condition might occur.
In the event of extensive venting during an accident, all the water in the water seal tank is carried away by the gas, leaving no water in the seal. In the current design, there are automatic inflation systems at both the front and back of the water seal tank, so it is not possible for there to be no nitrogen nor high-pressure fuel gas present; a slight positive pressure is always maintained. It should be ensured that the automatic valves are set to open in the event of an accident
After high-temperature gas is released in an accident scenario, if the negative pressure resulting from the drop in temperature cannot be compensated for in a timely manner, even a 3-meter-high water column will not be sufficient to prevent the water in the water seal tank from flowing back into the separation tank at the front end. Through design improvements, an annular structure can be added to the middle section of the 3-meter-high vertical pipe of the water seal tank. Increase the water storage capacity by a 3-meter water column. It can effectively prevent water from flowing back into the liquid separation tank due to negative pressure.
Improve safety through the structural design of the equipment itself, striving to achieve intrinsic safety of the equipment. Interlocked replenishment of nitrogen and fuel gas in the event of a vacuum serves as an alternative option.
I work in project management and production operations, and I would like to offer a suggestion: There is a delay in introducing nitrogen supplementation through the air release water seal tanks or main pipelines. Could the nitrogen supply points be located at the flare tip, with a nitrogen regulation valve installed there? The diameter of this valve should be 80–100. Nitrogen supplementation should start when the pressure is around 0.5 KPa; the lower the pressure, the greater the amount of nitrogen supplied. Could this approach be beneficial in preventing flashback accidents?