how do I calculate BTU of gas
how do I calculate BTU of gas
(OP)
how do I calculate BTU of gas, with composition of CH4, C2H6, CO2, N2, etc.
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how do I calculate BTU of gas

how do I calculate BTU of gashow do I calculate BTU of gas(OP)
how do I calculate BTU of gas, with composition of CH4, C2H6, CO2, N2, etc.
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RE: how do I calculate BTU of gas
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RE: how do I calculate BTU of gas
in a simple formula, if I have 99.5% CH4, 0.5% CO, what would the btu level be?
RE: how do I calculate BTU of gas
HV of gas = Sum [ (x_{1}) (HV_{1}) + (x_{2}) (HV_{2}) + (x_{3}) (HV_{3}) + ... ]
If your percentages are volume percents or mole percents (which are completely equivalent), then:
HV_{n} = heating value of gas component n, in kJ/m^{3}
x = (percentage/100) of gas component n
If your percentages are weight perecents, then:
HV_{n} = heating value of gas component n, in kJ/kg
x = (percentage/100) of gas component n
If you would rather use USA units than metric units, then:
Use Btu/ft^{3} and Btu/lb instead of kJ/m^{3} and kJ/kg
Also, be consistent. If you want the higher (or gross) heating value of the gas, then use the higher (or gross) heating value of each gas component. If you want the lower (or net) heating value of the gas, then use the lower (or net) heating value of each gas component.
Milton Beychok
(Visit me at www.airdispersion.com)
.
RE: how do I calculate BTU of gas
I was under a misimpression that some inerts (like CO2) had a negative impact to the Btu (i.e. if CO2=10%, CH4=90%) and drive the BTU to much less than the calculated 910Btu/Lb.
RE: how do I calculate BTU of gas
Inerts such as carbon dioxide or nitrogen simply have a heating value of zero. They should be included in the formula I gave you. Hence, they dilute the combustibles and do lower the heating value of the overall gas.
In other words, a gas containing 10% carbon dioxide and 90% methane will indeed have a lower overall heating value than a gas which is 100% methane. I guess you might consider that to be "negative impact", but that terminology really has no objective meaning.
Milton Beychok
(Visit me at www.airdispersion.com)
.
RE: how do I calculate BTU of gas
Sspence, don't confuse heating values with flame cooling effects which inert diluents may cause.