Selection of flowmeters for the two operating conditions
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I have a question for everyone. I’m working on a project where the requirements regarding the process involve the flow meter operating under two different conditions: sometimes it handles hot water, and other times it handles steam. However, these two conditions do not occur simultaneously. Which flow meter would be suitable in this case? The process pipe has a diameter of DN100; the material is carbon steel. The hot water flow rate is 35 m3/h, the temperature is 80°C, and the pressure is 0.3 Mpa. The steam flow rate is 600 kg/h, with a density of 2.39 kg/m3 and a temperature of 147°C, under a pressure of 0.35 Mpa.
The flow range, allowable pressure loss, whether metering is required, etc., must be specified. Refer to the recommendations first: the cheapest option are orifice plates, equipped with pressure compensation. Of course, I have no objection if you buy a mass flow meter. The DCS configuration accumulates either hot water flow or steam flow based on temperature.
The mass flow meter should be fine.
One is a liquid and the other is steam; in my opinion, it’s very difficult to measure them with a single flow meter!
Two different flowmeters are installed in parallel; the one that is not in use can be disconnected. It’s difficult to solve the problem with just one flowmeter, and mass flowmeters may not work either, plus they are very expensive.:o
High precision requirements require the use of mass flow meters~
Turbine flowmeters, mass flowmeters, and Anemometer flowmeters can all be considered; the user can select based on cost-performance.
This is a mass flow meter. I’ve seen them before; it was specified that a mass flow meter should be used in the process design, not necessarily because of its measurement accuracy, but rather because it allows for zone-based measurement during configuration. However, I don’t know why it was designed this way. It seems that in systems involving heat integration, there is a bypass line that enables the use of either hot water or steam – both options are possible
For this purpose, expensive mass flow meters are used, while inexpensive integrated orifice plate flow meters are used instead
The DCS is set with two FIs: A for hot water & B for steam 1. Orifice plate + one transmitter. Given your conditions, the steam flow rate is relatively low; therefore, the hot water flow rate corresponds to the operating condition specified for the orifice plate (which determines the size of the orifice), while the steam flow rate is calculated accordingly (based on the fact that the differential pressure remains constant). As a result, the orifice plate suitable for hot water has an upper flow rate of nearly 2300 KG/H under steam conditions, which is unfavorable for steam measurement as the range for steam is too large. 2. Orifice plate + two transmitters: The flow rate of hot water is the operating condition specified for the orifice plate design; for hot water, the parameters are FI-A (0–50 M3), a differential pressure of 50 KPA, and an orifice ratio of approximately 0.515. Steam transmitter, differential pressure of 10 KPA, corresponding flow rate FI-B (0–1073 KG). It’s this approach: ask the manufacturer for an accurate calculation. As for vortex flowmeters, the configuration density has to be modified every time there is a fuel replacement (due to differences in the medium), which is also troublesome; as for mass flowmeters, it depends on their cost-performance ratio. @jiaguoyun @Big Horse with a Big Bow