Patent ID: 7288690

Claim:
In a method of steam cracking hydrocarbons, which method consists in heating a mixture of hydrocarbons and steam to a desired temperature that is high enough to crack the hydrocarbons and transform them into olefins, the improvement wherein the source of energy for heating the mixture is supplied essentially by cogeneration using combustion of a fuel to produce simultaneously both heat energy and mechanical work which is transformed into electricity by an alternator or an electricity generator, wherein the mixture is initially subjected to preheating using the heat energy supplied by the cogeneration, and is subsequently heated to the desired cracking temperature by means of electrical heating using the electricity supplied by the cogeneration, and wherein the congeneration produces the heat energy in the form of hot combustion gases, with a fraction of the oxygen thereof being used as oxidizer for performing post-combustion and increasing the heat energy used for preheating the mixture to be cracked.