Which type of flow meter is more suitable for measuring gas-liquid two-phase flow media
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Hello, everyone who is into the sea! In distillation processes, the reflux liquid in the reflux line contains a significant amount of gaseous material. Which type of flow meter is suitable for measuring this flow (in the reflux line; no flow meter was installed there previously)? Thank you!
1. There are no shortcuts. 2. Phase separation measurement. 3. If you want to try something random, just draw lots. — For two-phase flow, there is no “most suitable” flow meter; only ones that are less suitable. — Inspection completed {:3_51:}
I’ve seen a method related to this for measuring two-phase flow; it’s very expensive and difficult to implement on a wide scale. Pig Brother 1111111’s phase measurement is a good method.
Measuring two-phase flow is a world-class challenge; the simplest approach is to separate the phases and measure the liquid and gas separately. Some two-phase flow measurement methods used in the oil production industry have a laboratory error of 5-10%, with errors that are likely even higher in actual operating conditions; therefore they are completely unsuitable for industrial use. For industrial applications, if it is necessary to measure two-phase flow, I recommend using the weighing method.
Thank you very much to everyone for your suggestions!
For distillation column reflux, no metering is required; it is a matter of process control. If the process conditions are stable – for example, if the gas-liquid ratio remains constant – then a simple rotameter should suffice.
Metal rotameters are not recommended for use when the medium contains gas and liquid; then, based on what medium should they be calibrated at the time of manufacture?
In the case of a clear gas-liquid two-phase flow, it is necessary during design to separate the two phases and measure them using appropriate flowmeters; this is not a difficult task in terms of pipeline and instrument layout. If the mixing of gas and liquid is good, that is, if the bubbles are distributed evenly in the liquid phase, mass flow meters that are suitable for multiphase conditions can be used for measurement. If it is in the gas phase and flows through the process pipeline in a gaseous state, there is no way to do anything without performing phase separation measurements. In the case of a two-phase liquid medium, depending on the mixing conditions, a mixer can be used along with flow velocity measurement to determine the total volume; a positive displacement flow meter can also be employed for this purpose.
From a process perspective, it is advisable to install a gas-liquid separator before the return line to the distillation tower, so as to remove the gas. What’s the purpose of allowing gas to enter the distillation tower? Since it is a fractional distillation process, that is, a distillation process, the side streams produced should all be liquids; only then will gas emerge from the top of the tower. Is the resulting fractionated product reheated again?
What’s said upstairs makes a lot of sense. I’ve learned it! ! !