How to Convert Cubic Meters of Liquid Natural Gas to Metric Tons

To change cubic meters into metric tons, the density of the gas first has to be determined. The density of liquid natural gas (LNG) is dependent on composition and temperature. LNG is typically over 90% methane, with ethane, propane and some longer hydrocarbons. The density of LNG is typically between 0.4 and 0.42 kilograms per cubic liter, making it lighter than water.

Things You'll Need

• Volume of LNG
• Calculator

Instructions

1. Determine the volume of LNG in cubic meters. This can be done by determining the volume of the storage tank and the level of LNG inside. There are 35.3147 cubic feet in a cubic meter. There are 1.30795 cubic yards in a cubic meter. Convert your volume of LNG to cubic meters.

2. Find the weight. Multiply the density (kg/liter) by the volume. First change kg/liter to kg/cubic meter. There are 1,000 liters in a cubic meter, so take the average density of LNG and multiply by 1,000:

   0.41kg/liter x 1,000 liters = 410 kilograms

   That is the weight of one cubic meter of LNG. Note that the actual density depends on the temperature of the LNG and the composition.

3. Multiply the total number of cubic meters by 410 kg/cubic meter. For instance, if you have 250 cubic meters of LNG:

   250 cubic meters x 410kg/cubic meter = 102,500kg.

4. Convert kilograms to metric tons. There are 1,000 kilograms in a metric ton, so divide your kilograms by 1,000:

   102,500kg / 1,000 = 102.5 metric tons

   Note that because the density value used in Step 2 has only two significant figures, the precision of the result should be properly stated as 1.0 x 10^2 metric tons. To obtain a more precise figure, the exact density of the gas should be calculated.

References

• CNG: Liquefied Natural Gas
• OnePetro: Density of Liquefied Natural Gas