I would like to know: when using gas to push water out of the pipeline from the bottom of the storage tank, it’s important that too much gas doesn’t enter the pipeline. What control solutions are available?
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I would like to know: when using gas to push water out of the pipeline from the bottom of the tank, as long as the liquid in the tank is emptied, it becomes impossible to install a level gauge in the tank. Moreover, too much gas cannot enter the pipeline. What control solutions are available? In other words, how can we determine the exact moment when the gas has emptied the storage tank and entered the pipeline? What instruments can be used for monitoring and controlling this process?
Just install a float-type on/off valve, that’s it
Is it possible for the outlet pipe to be U-shaped?
Can it detect with high sensitivity the different states in the pipe, such as being filled with water, air, or a mixture of both?
It functions similarly to a steam trap, you know?
It would be best to include a schematic diagram; the view from the second floor is correct – leaving a small amount of liquid at the bottom of the tank ensures that no gas will enter the pipes.
A orifice flow meter should be installed on the pipeline at the tank outlet; this flow signal can be utilized effectively to monitor the flow rate and to check whether gas is passing through the flow meter. An interlock system can also be added to control the shut-off valve
1. Rotameter: The flow of liquid is very smooth; once the liquid has run out, gas passing through it will cause the flow rate to reach its maximum value. 2. Pressure difference indication: There is a pressure difference between the two containers during transportation, and this pressure difference changes rapidly once the liquid has run out. When the container is large and the tube is small, it’s not noticeable. 3. The float valve mentioned above allows fluid to pass only when there is liquid present. The airtightness may not be very good, so it needs to be monitored promptly
I’m not sure if I’m thinking correctly... A chamber is pressurized from above, and then the pipe below uses that pressure to discharge fluid. If that’s the case, it would be sufficient to design two level switches: when the liquid level drops low enough, they can trigger the discharge solenoid valve to close. As for why two switches are needed, it’s because one can be set at a higher level and the other at a lower level; the one at the higher level will activate and close the valve, while the one at the lower level serves as an additional safety measure. In this way, there’s less risk of gas escaping through the pipe
Perhaps the tank has already been shaped and there is no space for a level gauge interface, so a level gauge cannot be installed. Are there any level gauges that can be installed without such an interface? The radar level gauge seems to be inaccurate
It is possible to install the outlet valve of the tank at the bottom of the tank, with the outlet pipe shaped in a U-shape so that its lowest point is below the bottom of the tank. Differential pressure switches or transmitters can be installed on both sides of the U-shaped pipe; there will definitely be a differential pressure between the gas and the liquid, and judgments can be made based on this differential pressure value