3 replies to this topic

[ivanwg]

hi everybody

I'm making a natural gas liquefaction in HYSYS, I have natural gas composition: 0.51 % N2, 95.96% CH4, 2.02% C2, 1.01% C3, 0.25% i-C4, 0.15% n-C4, 0.05% i-C5, 0.03% n-C5 and 0.02% C6+, I don't have molecular weight of C6+, neither its boiling point to input it into Hysys, there are many correlations but i don't know more data, how i can calculate molecular weight of C6+ just knowing natural gas composition? thanks in advance

Ivan Wilson

[PaoloPemi]

if you have no additional data (dew point, phase envelope, boiling point etc. etc.) you can only guess the composition of C6+ , typical split is C6+ to 50% n-Hexane, 50% n-Heptane see GPSA for additional information but there are alternative ways.
Be careful that in many cases these methods can produce wrong dew points, a little percentage of heavy components has great influence on dew points.
I prefer to match the list of components to some measured points but that requires additional data (see Prode documentation for additional information about this method).

[ankur2061]

Ivan,

PaoloPemi himself had posted at the link below a very good discussion on C6+ characterization. Have a look:

http://www.eng-tips.....cfm?qid=290989

Some more links provided below may help:

http://www.psig.org/...s/2000/0106.pdf

Also refer an excellent description on C6+ characterization and molecular weight of petroleum fractions in Chapter 6 - Production Engineering in the book "Standard Handbook of Petroleum and Natural Gas Engineering - Volume 2" by William C Lyons.

Hope this helps.

Regards,
Ankur.

[ivanwg]

Thank you both for your great help!