Process and apparatus for decoking a hydrocarbon steam cracking furnace

A process for the decoking of a hydrocarbon steam cracking furnace having a firebox, radiant coils, a transfer line exchanger, and an oil quench connection wherein liquid quench oil is injected to directly cool the steam-cracked effluent. Decoking feed comprising steam and air is supplied to the furnace under conditions sufficient to at least partially combust coke accumulated on the interior of the radiant coils, the transfer line exchanger, and the quench connection. Quench steam is supplied and injected into the decoking process effluent in an amount sufficient to cool the decoking process effluent below the metallurgical temperature limit of downstream piping. Also, a pyrolysis furnace for the production of ethylene is also provided. 种用于具有燃烧室、辐射盘管、转移线交换器和油骤冷连接部分的烃蒸汽裂解炉的除焦方法，其中将液体骤冷油注入以直接冷却蒸汽裂解的流出物。在足以至少部分燃烧在辐射盘管、转移线交换器和骤冷连接部分内部上累积的焦炭的条件下将包含蒸汽和空气的除焦物料供应到炉子中。以足以将除焦工艺流出物冷却到低于下游管线冶金温度极限的九量供应骤冷蒸汽并将其注射到除焦工艺流出物中。此外，本发明还提供了种用于乙烯制备的热解炉。