Gas Calculation
Gas Calculation
(OP)
Hello,
I was tasked today on how much it would cost for us to fill 19 miles of 12" schedule 80 pipe with pipeline grade methane at 150 psi.Any help in calculations I should use to figure out roughly how many Dekatherms would be greatly appreciated.
I was tasked today on how much it would cost for us to fill 19 miles of 12" schedule 80 pipe with pipeline grade methane at 150 psi.Any help in calculations I should use to figure out roughly how many Dekatherms would be greatly appreciated.





RE: Gas Calculation
19 miles long line contains 70,806 ft3
Now you start with p*V*M = z*m*R*T and since you know all the terms except mass, it is easy to calculate the quantity (kg or lb) of Methane. Compressibility factor should be around 0.985 at 150 psi(g).
Methane heating value (LHV) is 21,433 BTU/lb. Mass times LHV and there you are.
Dejan IVANOVIC
Process Engineer, MSChE
RE: Gas Calculation
ρstd=(Pstd*SG)/(Rair*Tstd*Zstd)=0.046 lbm/ft3
ρactual=(Pactual*SG)/(Rair*Tactual*Zactual)=0.479 lbm/ft3 (assuming that the gas is at 60F)
So:
qstd=Vol*ρactual/ρstd=739 MSCF
Since methane contains a LHV of 909 BTU/SCF and a dekatherm is 1 MMBTU, it is 672 dekatherms
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
RE: Gas Calculation
RE: Gas Calculation
http://www.peacesoftware.de/einigewerte/methan_e.h...
70,806 ft3 * 0.441 lb/ft3 * 21,433 (net heating value) = 669 dekatherms
RE: Gas Calculation
672 Deks / 909 * 1025 = 757 Deks
RE: Gas Calculation