Accurate measurement of steam condensate
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In pipes, steam condensate is generally in a two-phase flow state of vapor and liquid. What good methods are there to measure the flow rate accurately?
Install the condensate tank. Pump the condensate, and install electromagnetic flowmeters in the pipe tray for monitoring.
It seems that there isn’t yet any very good method for measuring the flow rate of gas-liquid mixtures. What was said on the second floor makes sense; it’s possible to use devices to measure the flow rates of the gas phase and the liquid phase separately.
It’s very simple – use a mass flow meter!
If the steam condensate is in a two-phase flow state, it is practically impossible to achieve accurate measurement. It is recommended that the person in question install a steam trap before recovering the steam condensate; regular measuring devices can easily handle the measurement after the valve
The reply on the second floor is incorrect. The limitations of electromagnetic flowmeters are: 1. The temperature of the medium should not be too high; generally, it should not exceed 120 degrees. If there is a two-phase vapor-liquid mixture present, this temperature is likely to be exceeded. 2. The medium to be tested must be a conductive medium, and it should not contain too many bubbles. So an electromagnetic flowmeter definitely can’t be used.
The flow rate of a two-phase medium cannot be measured. If the intention of wrapping around is to measure the flow rate of the condensate, I think it can be done as follows: 1. The steam generated by installing a flash tank can be reused as well ； 2. The condensate transfer pump increases the transfer pressure and also prevents the condensate from vaporizing again, which could affect flow measurement ； 3. Vortex flow meters can be installed in the boundary zone; if the condensate temperature is still high, a split-type version can be used. That’s how our company uses it, and the results are excellent. This post was last edited by frankqe on 2008-2-14 13:24]
What was said upstairs was very detailed. But they’ve already installed a condenser tank – why can’t it be used? :)
Even with a condensate tank installed, an electromagnetic flowmeter cannot be used to measure the flow rate of the condensate.
I’m very grateful for everyone’s enthusiastic discussions. What troubles me is the issue of measurement accuracy; I have tried methods such as vortex flow meters and ultrasonic sensors, but the errors are quite large. Electromagnetic methods have also been considered, but they are not viable options. In condensate pipes, flash vapor is inevitable; as a result, the flow in these pipes is often not full-flow. Steam has very poor electrical conductivity, so the results obtained from measurements are predictable. Mass flow meters should be capable of performing measurements, but two factors limit their use in such systems. Firstly, mass flow meters are generally quite expensive, especially when they have a larger diameter ； Furthermore, local water hammer caused by secondary steam in the condensate pipes poses a fatal threat to mass flow meters. I have been working on steam energy conservation, and the measurement of condensate water has never been a straightforward issue. I hope to find a method that is acceptable to customers and yet provides accurate measurements. This post was last edited by fan*aoqi on 2008-2-14 20:56.]
To achieve accurate measurement, it is necessary to add a vapor-liquid separator: the liquid exits from the bottom of the separator while the vapor exits from the top. This makes it simple to measure whatever parameter is required (all that’s needed is to select the appropriate instrument based on the properties of the medium)
Steam condensate is a two-phase flow, and there is basically no accurate method for measuring the flow rate of these two-phase fluids. 1. Install a condensate tank; the condensate transfer pump is used to transport the condensate, increasing the transfer pressure to prevent the condensate from vaporizing again, which could affect flow measurement. It is recommended to install electromagnetic flowmeters on the pipe tray for monitoring. 2. Install a steam trap before the recovery of steam condensate, and a flow meter behind the valve. 3. Install vortex flow meters in the boundary zone; if the condensate temperature is too high, a split-type installation can be used. 4. If none of them are allowed, then use vortex flow meter measurement as a reference!
I couldn’t see clearly; it’s steam condensate, and its low conductivity means it cannot be used in electromagnetic flowmeters.
It should work to use an orifice plate after the pump is pressurized, right?
Well, even after reading to the end I didn’t see any recommended method that works well after trying it out. Our company also needs to install one now, but we still don’t know which type of meter to choose
:L :L :L :L :L :L :L :L :L :L
In my opinion, a storage tank should be installed at the outlet of the imported steam condenser to maintain a certain pressure. Then pump it to increase the pressure and prevent vaporization. Installing a liquid flow meter should enable accurate measurement. If that still doesn’t work, add a condenser at the pump outlet to cool the steam. It mainly depends on whether you want the steam to cool down.