Propane, in Heidelberg, is a commercial gas used commonly as a fuel for engines, portable stoves, oxy-gas torches, barbecues, central heating, etc., obtained as a by-product of natural gas processing and petroleum refining processes. When mixed with butane, it is known as Liquefied Petroleum Gas, which is mainly used as vehicle fuel & in kitchen cylinders. Propane produces about 50 MJ/Kg heat when combusted properly. Generally it is non-toxic. But prolonged inhalation might cause mild asphyxia because of oxygen deprivation. Propane is stored under pressure at room temperature. When released, it expands & cools rapidly causing frostbites on exposure. Propane combustion, though not as clean as that of natural gas is comparatively cleaner than gasoline. It is also used for providing off-the-grid refrigeration in gas absorption refrigerators.
Other uses of propane include- semiconductor manufacturing for depositing silicon carbide, as feedstock for producing base petroleum, propyl alcohol, as a primary fuel for hot-air balloons.
Being heavier than air, a leak in the propane fuel system may cause sinking of the gas into any enclosed area and thus has a significant risk of explosion. However, compared to CNG or compressed natural gases, Propane is easier to store in relatively smaller place, in an economical way & thus provides a convenient & commercial source of fuel in Heidelberg.