Steam condensate metering issues
Steam condensate metering issues
(OP)
I am looking at the existing condensate metering system at a site where there is a wide gap between steam flow rate and condensate flow rate(condensate being about 40% lower).The condesate is pumped back to the feed tank by means of pump trap units which produces a pulsating flow.The flow rate varies from 2000kg/hour to 15000 kg/hr depending on steam demand.What will be an ideal type of flow meter(totalizing type) for this application?Will a single meter be ok or two in parallel /
Thanks in advance
Thanks in advance





RE: Steam condensate metering issues
Positive displacement meters work well in condensate line well. I don't see any reason as to why single meter will not work.
RE: Steam condensate metering issues
RE: Steam condensate metering issues
RE: Steam condensate metering issues
RE: Steam condensate metering issues
If you have those steam driven 'pump/traps' they have available a cycle counter, since each cycle is a fixed volume of fluid, you could use this to calculate flow.
RE: Steam condensate metering issues
In any case, 40% seems to be quite huge. Your turndown ratio is about 7.5 and my experience with orifice flow meters with such turndown ratios is bad. A couple of things here for you to check.
Since, your condensate temperature is 70C, there must be some flashing. If your steam pressure is 10 barg, you have approximately 21% flashing.
Check the rate of flashing corresponding to your steam pressure.
If it is superheated steam then you require both temperature as well as pressure readings for density compensation.
Check at what flow rate the difference is significant. If the difference is higher at peak flow rate and lower at lower flow rates then the DP transmitter may not suit your application. You may have to go for two transmitters instead.
Steamdog's suggestion of counting pumping trap is good. If you don't have this provision then try to do condensate receiver fill test(isolating fresh water feed).
Good luck,