HHV of natural gas components
HHV of natural gas components
(OP)
I am looking for HHV of natural gas components calculated at 15 C and 101.325 kPa. Is there a table on the web somewhere?
I found the values at 60 F and 14.69 psi in a couple of my text books but can't find them at the SI standard.
I found the values at 60 F and 14.69 psi in a couple of my text books but can't find them at the SI standard.





RE: HHV of natural gas components
The thing to keep in mind is that STP is in no way "standard". It is a contractual item for gas sales and the contract is a likely to say 0 C as 15 C and the 101.325 kPa often becomes 100 kPa or 1 bar(a), or some other number that the contract negotiators pull from the air. The RefProp program will handle any of these, the GPSA book uses a single value (I don't use the SI version so I don't know what their "Standard" is).
David Simpson, PE
MuleShoe Engineering
www.muleshoe-eng.com
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
Remember, being ignorant isn't your fault; staying ignorant is.
RE: HHV of natural gas components
Value * (101.325 KPA) / (14.68 PSI * 6.894) * ((60°F - 32) / (1.8) + 273.15) / (15 C + 273.15)
hoping there are no errors, in the first part you convert from PSI to KPA, in the second part from F to K (you need to use the absolute temperature), taking in account that the mass (quantity of substance) contained in the "normal" volume is directly proportional to the reference pressure and indirectly proportional to the reference temperature
as already mentioned there are many software utilities which do these calc's, if you do a search with Google you'll find lots of free programs, I use Prode Properties but I suppose that any other tool can do the work.
RE: HHV of natural gas components
http://www.gpaglobal.org/
you are looking for GPA 2145-09, just released about 3 months ago. If you need EXACT content for real gases, then you need to use GPA 2172. REFPROP does not perform the detailed calculations that would be required for custody transfer.