Designing a Multi-Fuel Station: Positioning of CNG Nozzle
When designing a fuel station that dispenses gasoline, diesel, and compressed natural gas (CNG), one important consideration is the placement of nozzles. Typically, the CNG nozzle is positioned to the left of the diesel nozzle. This arrangement is not merely for aesthetic reasons but is rooted in practical considerations related to the hand preference of the equipment used to fill vehicles. CNG is dispensed from left-handed nozzles while diesel is dispensed from right-handed nozzles.
Why is the Relative Position Important?
One might ask: why should the relative position of the nozzles matter, so long as they are clearly differentiated and well-advertised? The answer lies in the human factor. Despite clear signage and promotional efforts, human error can still occur. Different informational pictograms and colored hoses can help in distinguishing between the nozzles, but there is no substitute for a design that minimizes the chance of mistaking one for the other.
Proper Fuel Station Design
A properly designed fuel station should prioritize safety and convenience. One key aspect is the separation of CNG/LNG/LPG/H2 dispensers from the others, especially for the nozzles. These should be placed at the perimeters of the compound, ensuring that people using these nozzles are not standing next to each other, reducing the risk of accidents.
Dispensing Gaseous vs. Liquid Fuels
Generally, gaseous fuels will not be dispensed from the same equipment as liquid fuels due to differences in equipment design and pressure requirements. The pumps, meters, plumbing, and hoses used for gaseous fuels are dissimilar to those used for liquids. This is because gases need to be greatly compressed to provide practical use, resulting in higher pressures that are necessary for handling gaseous fuels. Unlike liquids, which are dispensed at atmospheric pressure, gaseous fuel cannot flow into a tank by gravity.
For fuel stations that sell CNG along with gasoline and diesel, a separate dispenser will be provided. This dispenser is often positioned on its own island, ensuring separation from other fueling stations. In Australia, for instance, almost all fuel stations also have Auto LPG available, where the filler pump for CNG must be separate and uses a pressure nozzle.
Additional Design Considerations in Australia
In the context of Australia, where diesel filler handles are typically black, the LPG pump is a completely separate unit. This separation ensures that vehicles needing LPG have a dedicated and well-marked station, reducing the risk of user error.