What about level detection in two-phase substances?
Thread Content
I work in the process field, and when filling out the forms I came across a statement that says: \"When there are two-phase substances during level detection, it is necessary to enter the specific gravity of each phase separately.\" The device whose level needs to be monitored is a desorption tower; it has a certain amount of liquid at its bottom, with carbon dioxide gas generated through desorption above that liquid. Should I provide the severity of carbon dioxide? What impact does the concentration of this carbon dioxide have on the level gauge? I would appreciate the guidance from all the teachers.
I don’t think it has any impact on the sealed container.
When measuring the interface, it is necessary to know the densities of the two media. However, the gas-phase medium is gaseous CO2, so it should not be needed. If a double-flange level gauge is used, the pressure of CO2 is equal in the positive and negative chambers, thus balanced out, which does not affect the measurement results.
This rule requires that their severity level be specified, as it has an impact on the changes in stress testing. It’s useless if pressure is not used to measure the liquid level!
The density of carbon dioxide has an impact on the measurement results, especially in high-pressure conditions. When the gas pressure exceeds 30 KG, carbon dioxide undergoes significant changes in density, which directly affects the measurement results. On the third floor, it was said that \"if a double-flange level gauge is used, the pressure of CO2 is equal in the positive and negative chambers, thus balanced out, and this does not affect the measurement results.\" ”The result is based on the assumption that the effect of carbon dioxide can be ignored; if the gas phase pressure is high, the pressure difference caused by CO2 cannot be balanced.
The maximum pressure in this process tower is 0.5 MPa, so it may not be necessary to introduce a gas phase.
Many of our towers contain a vapor-liquid two-phase mixture, and for most of them magnetostrictive level gauges are used, which do not require information regarding the vapor density. In the case of an interface between two liquids, it is necessary to know the specific gravities of both liquids, as the difference in their specific gravities is used to select the appropriate float, that is, to determine the volume and weight of the float.
In level measurement, the density of the gas phase is not required; only the density of the liquid phase is needed.