... hot flame (2,976°C) with a high heat release in the primary flame (inner cone) (15,445kJ/m 3 ), less than ... propane (10,433kJm 3 ). The secondary flame (outer cone) also gives off a high heat release, similar to propane and natural gas ... scientific blend proportion and favorable flame characteristic ELK Map gas is a mixture of various hydrocarbons, principally, methylacetylene and propadiene.