MMSCF (Million Standard Cubic Feet) is a imperial unit that generally refers to the volume of natural gas when the temperature and pressure are 60 ℉ (15.56 ℃) and 14.696 psi (101.325 kPa), respectively.
Therefore, when want to find the mass of natural gas, you can find the mass of natural gas by multiplying the volume under these conditions by the standard density.
Calculation example) First, if the volume is converted to normal conditions (0 ℃, 101.325 kPa) based on Korea Gas Corporation,
1 SCF = 1 ft3 (60℉, 14.696 psia) = 0.02832 m3 (0℉, 14.696 psia)
= 0.02679 m3 (0℃, 101.325 kPa) = 0.02679 Nm3
= 0.02679 m3 (0℃, 101.325 kPa) = 0.02679 Nm3
Therefore, 1 MMSCFH = 0.02679 * 10^6 Nm3 = 26,790 Nm3/hr