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How to convert Kg/hr to Nm3/hr
- Thread starter purdster
- Start date
Nm3/h is commonly used as a unit of measure for flow of compressible fluid (e.g. vapour) because the volume varies with pressure.
If your flow is LIQUID ammonia then you can pretty safely assume that this is incompressible and thus volume does not vary with pressure (density is constant with pressure).
Simply divide the kg/h by density (kg/m3) to get m3/h (actual m3 of ammonia flowing per hour).
If your flow is LIQUID ammonia then you can pretty safely assume that this is incompressible and thus volume does not vary with pressure (density is constant with pressure).
Simply divide the kg/h by density (kg/m3) to get m3/h (actual m3 of ammonia flowing per hour).
Another way of saying that is that Nm3/h or SCFM do not have any meaning for liquid flows because the difference in density between 0C and 0 barg and 15C and 17.5 barg is very small. I suppose you could come up with your own (maybe convert actual cubic meters per hour to a water equivilent, but why?).
David
David
- Thread starter
- #4
Unless I am sadly wrong, there are two commonly used volumes;
1) the volume at actual conditions which you obtain by dividing by the density at the process temperature
or
2) the standard volume where you divide by the density at 15degC (or, 60degF dependent as appropriate).
These calculations are quite familiar (the other way round) in hydrocarbon metering where volumetric flow measurements are often made but where the mass is required, and often the volume amounts are recorded as at standard conditions rather than the sometimes variable process conditions.
JMW
1) the volume at actual conditions which you obtain by dividing by the density at the process temperature
or
2) the standard volume where you divide by the density at 15degC (or, 60degF dependent as appropriate).
These calculations are quite familiar (the other way round) in hydrocarbon metering where volumetric flow measurements are often made but where the mass is required, and often the volume amounts are recorded as at standard conditions rather than the sometimes variable process conditions.
JMW
FYI,
"We don't believe things because they are true, things are true because we believe them."
"We don't believe things because they are true, things are true because we believe them."
David,
Flareman stated: "Nm^3 are Normal Temperature = 0 degC (273.15 degK) Pressure = 760 mm Hg"
The link namely shows that many different definitions of standard references conditions are currently being used by organizations all over the world...
"We don't believe things because they are true, things are true because we believe them."
Flareman stated: "Nm^3 are Normal Temperature = 0 degC (273.15 degK) Pressure = 760 mm Hg"
The link namely shows that many different definitions of standard references conditions are currently being used by organizations all over the world...
"We don't believe things because they are true, things are true because we believe them."
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