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Flow Rate Question

03/11/2017 6:10 AM

how do i the discharge convert Nm3/hr to m3/hr and Nm3/hr TO Kg/hr

FLOW MEDIUM :BF GAS

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#1

Re: FLOW RATE

03/11/2017 6:16 AM
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#3
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Re: FLOW RATE

03/12/2017 9:24 PM

GA

The OP should be very careful. Boron Trifluoride is a poisonous gas that can be very nasty.

Blast furnace and boiler flue gas with their varying concentrations of carbon monoxide gas can be just as deadly.

Eschew obfuscation.

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#2

Re: FLOW RATE

03/11/2017 2:44 PM

Multiply the volume flow rate by the density of the gas at the relevant temperature and pressure conditions.

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#4

Re: Flow Rate Question

03/13/2017 11:12 AM

what is an Nm3/hr? I do not remember that unit of measure from screwall.

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#5
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Re: Flow Rate Question

03/13/2017 11:46 AM

"N" stands for normal, as in normal pressure and temperature. 1 atmosphere and 25 degrees C. Normal temperature can vary between industries.

Source.

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#6
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Re: Flow Rate Question

03/13/2017 11:51 AM

Normal? I thought the guy's name was Norman.

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#7

Re: Flow Rate Question

03/13/2017 12:29 PM

i got an answer that by multiplying density of gas to its discharge(in Nm3/hr) we could get discharge in (kg/hr). my next doubt is how to convert (Nm3/hr to m3/hr)

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#8
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Re: Flow Rate Question

03/13/2017 1:12 PM

wouldn't you want to convert the raw number m3/hr, and convert that to Nm3/hr conditions of 1 atmosphere pressure and 298.15 K? Use the ideal gas law probably, or use a more suitable equation of state for the gas in question if the pressure and temperature are far from normalized conditions.

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#9
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Re: Flow Rate Question

03/13/2017 5:07 PM

...or use a set of tables for the particular fluid at those different conditions of temperature and pressure. GA.

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#11
In reply to #9

Re: Flow Rate Question

05/17/2017 2:09 PM

what is mean by set of table can u explain..

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#14
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Re: Flow Rate Question

05/17/2017 3:12 PM

In the case the compressibility of the gas is not a constant at the T,P required during measurement, there will be a different equation of state than the ideal gas law.

That equation can be used if the coefficients in the expansion of terms is known for that gas. Or in some engineering tables, the values for that gas are tabulated, to show corrected volume to reference given P,T, and volume of gas at P,T.

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#10
In reply to #8

Re: Flow Rate Question

05/17/2017 2:06 PM

how do i convert with help of ideal gas law (i.e pv=mRT)right..

can you explain please..

sry for the late reply...

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#12
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Re: Flow Rate Question

05/17/2017 2:47 PM

First, the equation is pv=nRT. If one solves for n and one uses the correct value for R to match your pressure, volume and temperature units you are using then this will tell you the number of moles of molecules that are in the volume of gas moved in an hour. If this was my facetious suggested gas of purely Boron Trifluoride then a simple lookup using the periodic table for the molecular weight will allow for a simple conversion of moles to mass being moved. However, if this actually is boiler flue gas then questions on how complete were the combustion and how much soot and condensate gets formed can make estimating the molecular weight difficult.

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#13
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Re: Flow Rate Question

05/17/2017 3:09 PM

It all depends on the pressure, temperature, and any non-linear compressibility of the gas. In some instances, the ideal gas law (PV=nRT) is sufficient, and one would correct the volume flow Q as follows:

Qstp = Qmeas x P(atm)/1 x 273.15/T, since 1 atm and 273.15 °K are standard temperature and pressure, except in the oil patch, and natural gas is referred to standard flow at atmosphere, and 294.2 °K.

The definition of one standard cubic foot of gas is stated below:

"A standard cubic foot of gas is defined as a cubic foot at a temperature of 21 °C (70 °F) and a pressure of 101.35 kilopascals (14.696 psia)". ... Common units of gas volumes include ccf (hundred standard cubic feet), Mcf (thousand standard cubic feet), MMcf (million standard cubic feet),.

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