What are the attributes of CNG?
When refueling a CNG vehicle for the first time, one will quickly realize that the refueling process of a CNG vehicle is slightly different from refueling a petrol vehicle. The reason for that is very simple: CNG is in a gas state, not a liquid state, like petrol. A gas has different physical attributes compared to a liquid. If the cylinder is depleted and refilled with CNG, the cylinder will get warm (not hot). This is absolutely normal and there is nothing to be concerned about. If a gas is put under pressure, the density of the molecules will increase, and therefore the temperature will rise. It will take some time, until the cylinder has adopted the temperature of its environment again. The table below indicates some of the attributes of different fuel types. CNG has a very high Research Octane Number (RON). Cars with fine tuned engines can optimally profit from this. The greater the octane number the greater the fuel compression ratio. Thus, there will be a higher combustion tempe
