Natural gas (mainly methane CH4) is generally cooled to about -163 °C and converted to liquid form. Liquefied natural gas (LNG) is only 1/600 of the volume of gaseous natural gas at atmospheric pressure.

Reducing the volume of natural gas makes it more useful to transport it over long distances and via specially designed cryogenic sea vessels (LNG ships) to places where there are no pipelines. Imported LNG is normally converted into gaseous natural gas after being heated from the ground through an offshore DE novo gasification terminal.

The composition of liquefied natural gas produced around the world varies, depending on the nature of the reservoir liquid, whether it is related to oil production and the weight of the LPG extracted during the liquefaction process. To make matters worse, countries have different gas targets for historical reasons. For economic reasons, LNG exporting countries have restrictions on the amount of nitrogen in their products. Because nitrogen is difficult to liquefy, there is not much commercial value for these countries unless the product can be sold to a high calorific value (HHV) or Wobbe index (WI) market with lower constraints.

To ensure that DE novo gasified LNG can be safely and usefully incinerated, new LNG must be interchangeable with the gases used by users. It is measured by the Wobbe index (WI), which can be used to measure the similarity between the incineration function of one gas and that of another. Nitrogen ballast will greatly affect WI targets. Since nitrogen is an inert gas, adding nitrogen to LNG will reduce the high calorific value of DE novo LNG. At the same time, nitrogen will be added to the LNG in the future to add the relative density of the mixture. The relative density of nitrogen (0.969) is much higher than that of methane (0.556).

Nitrogen injection is a proven safety skill that can be used to adjust the quality of LNG when its concentration exceeds the local network's skill targets.