People frequently wonder how to convert a volume of natural gas (e.g., standard cubic feet) to pounds (mass) and pounds of natural gas to volume. Here are some equations to employ, along with a more in-depth explanation later in this blog post.
Natural gas conversion The volume of gas in standard cubic feet and the molecular weight of natural gas are needed to convert volume to weight (mass). A sample computation with formulae to utilize can be seen below.
The ideal gas law conversion factor is based on the connection that 1 lb-mole of an ideal gas occupies approximately 379.3 SCF at 60F and 14.7psia (see Reference 1). Compressibility factors (Z-factors) are typically not employed in air quality regulatory calculations for natural gas and its components since a perfect gas is assumed.
Because the volume produced will be reported as standard cubic feet (SCF) at 60 degrees Fahrenheit and 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch at 14.7 pounds per square inch (see Reference 1 below). The mass amount (e.g. pounds or tons) of the gas discharged to the environment is typically expressed in air quality rules.
If you want to interact effectively with field operations, you’ll need to be able to convert between pounds (lbs) of gas (weight) and SCF (volume), as well as vice versa.
- psia = absolute pounds per square inch
- psig stands for pounds per square inch gauge, with 0 psig equaling 14.7 psia (most common units for gas pressure in oilfield). If the gas units are in psig, multiply the gauge pressure by 14.7 to get the absolute pressure (psia).
Natural gas at standard circumstances is a term used in oilfield operations to describe gas levels measured at:
60 degrees Fahrenheit and 14.7 pounds per square inch of pressure
Even if the actual temperature and pressure of the gas produced were higher, if you have 1000 SCF of natural gas, it is based on the natural gas at standard conditions of 60F and 14.7 psia. If you have actual pressure and temperature, you’ll need to convert the gas volume to standard circumstances by converting the temperature and pressure of the gas.
Because most production reports and gas analysis will already be in SCF, there should be no requirement for conversion.
The conversion of actual conditions of 1000 cubic feet of natural gas at 100 degrees Fahrenheit and 100 pounds per square inch to standard conditions is shown below.
- 1000 cubic foot = V2 (actual)
- P2 is equal to 100 psig (actual)
- T2 = 100 degrees F (actual)
The link between Boyle’s and Charles’ laws is used in the formula to convert from actual to standard conditions:
To utilize Equation 4, first convert the actual pressure (P2) to psia (by multiplying the psig value by 14.7), then convert the actual temperature (T2) to degrees Rankine, R. (by adding 459.67 to the actual temperature in F).
Equation 5 is used to solve for V1 (standard circumstances volume):
- August 2009, Compendium of GHG Emissions Estimation Methodologies for the Oil and Gas Industry
- Engineering Data Book of the GPSA
- Combustor unit for glycol dehydrators made by BTEX
- Glycol reclamation system on wheels
- Vapor Recovery Units (VRUs) are a type of vapor recovery (VRU)
- Towers for Vapor Recovery (VRT)
- Combustion Devices with Enclosures (ECD)
- Services for Leak Detection and Repair (LDAR)
- Services for vent gas measurement
What is the weight of a pound of gas in an inch?
If your pressure gauge reads 2 pounds, for example, enter 2. This is your conversion factor: 1 pound per square inch of pressure equals 27.78 inches in a water column.
In a pound of natural gas, how many cubic feet are there?
Convert energy between foot pound force (ft lbf) and cubic feet of natural gas (cu ft N.G.) units in the reverse direction (cu ft N.G. to feet pounds force).
2 psi natural gas equals how many inches of water column?
When using 2 PSIG pressure, 1/2- or 3/4-inch pipe is often utilized for this run, as opposed to the 1 or 1-1/4-inch pipe commonly used in low-pressure systems. A line regulator reduces the natural gas pressure to the usual 8-inch WC once inside the dwelling unit.
What is the standard unit of measurement for natural gas?
At the resource well, natural gas (methane) is measured in volume (cubic meters or cubic feet). At standard temperature and pressure, one cubic foot of natural gas equals the volume of gas contained in one cubic foot.
Which is heavier, natural gas or air?
Natural gas is lighter than air, therefore when it is discharged, it quickly dissipates into the atmosphere. When natural gas is burned, it produces a high-temperature blue flame and complete combustion, which results in just water vapor and carbon dioxide. Its heating value per cubic foot is around 1000 BTUs.
What is the definition of a mole of natural gas?
A mole is the amount of a substance that includes the same number of units as the number of atoms in 12 grams of Carbon12, which is 6.022 x 10-23, or Avogadros number.
What is the formula for converting pounds of gas to cubic feet?
1. Subtract 359 from the gas’s molecular weight. 2. To convert to cubic feet, multiply the result by the quantity in pounds.
How can you figure out how much natural gas there is?
Divide the appliance input by the average Btu (kW. h) heating value per cubic foot of gas to get the cubic feet per hour of gas required. The Btu per cubic foot average is 1,100.
What is the volume of natural gas in a normal cubic foot?
Because natural gas is an inaccurate mixture of numerous molecular species, primarily methane but with varying quantities of other gases, a standard cubic foot of natural gas is a molecular quantity, expressed in moles, rather than an exact unit of mass.
The standard cubic foot (scf) is defined as one cubic foot of gas at 60 degrees Fahrenheit (288.7 degrees Celsius; 15.56 degrees Celsius) and normal sea level air pressure. The definition of pressure varies depending on the source, however it is all close to average sea level air pressure.
- 14.696 pound-per-square-inch pressure (1.00000 atm; 101.325 kPa). This is the same pressure as the standard pressure in the SI system. The result is 1.1953 moles per scf.
- A pressure of 101.35 kilopascals was recorded (1.0002 atm; 14.700 psi). The result is 1.1956 moles per scf.
- A 14.73 pound-per-square-inch pressure (1.0023 atm; 101.56 kPa). This figure is pretty near to the mercury level of 30 inches. 0.002641 pound moles per scf or 1.1981 moles per scf
Within the SI system, the standard cubic meter of gas (scm) is used. It is also described as the amount of gas contained in a cubic meter at a temperature of 15 degrees Celsius (288.150 degrees Fahrenheit; 59.000 degrees Fahrenheit) and a pressure of 101.325 kilopascals (1.0000 atm; 14.696 psi).
The difference in base temperature and pressure utilized when converting volume units between the standard cubic foot and the standard cubic meter is not accurate, but it may be ignored in most practical applications. When the same volume is compared between the 15 C (288.15 K) and 101.325 kPa standard cubic meter and the 60 F (288.71 K) and 14.73 psi (101.56 kPa) standard cubic foot, there is a 0.04 percent difference. In the US Customary System, a standard cubic foot is roughly comparable to 0.02833 standard cubic meters in the SI system.
Large multiples of standard cubic feet are often not stated with metric prefixes in the natural gas business, although amounts are often written in standard cubic feet, but rather using prefixes based on roman numerals, where the s for “standard” is often removed. Gas quantities are commonly measured in ccf (hundred standard cubic feet), Mcf (thousand standard cubic feet), and MMcf (million standard cubic feet) (million standard cubic feet). The M stands for thousand in Roman numerals, while two Ms stand for one million. There are also terms like Bcf (billion standard cubic feet), Tcf (trillion standard cubic feet), Qcf (quadrillion standard cubic feet), and so on.