The amount of potentially recoverable NGL based from a natural gas stream can be estimated from the following formula:
Potential NGL component (tons per annum) = V*y*CF
where:
V = Volume flow rate of natural gas, MMSm3/day (Std conditions are P= 1.01325 bara, T = 288.15K)
Note: MM= Million
y = mole percent of the component in natural gas
CF = Component factor (see table below)
Example: 3 MMSCMD of NG is available for processing. This gas contains 5.4% mol propane. What is the potential propane recovery from the NG?
Calculations:
Potential Propane Recovery (w/o Recovery factor and plant on-stream factor) = 3*5.4*6800 = 110160 t/a
Considering a plant recovery factor of 70% and plant on-stream factor of 335 days, the average propane recovery per annum would be:
110160*0.7*(335/365) = 70,770 tons per annum (t/a)