Ethylene is the core of the petrochemical industry, ethylene cracking furnace is the core equipment of ethylene production plant, the main role is to process various raw materials such as natural gas, refinery gas, crude oil and naphtha into cracked gas, and supply to other ethylene plants, and finally process into ethylene, propylene and various by-products.

Ethylene cracking furnace structure

The cracking furnace is generally composed of convection section, radiation section and quench system.

The high thermal energy required for the reaction is provided in the radiation section by burning the fuel through a burner.

The purpose of the convection section is to recover the residual heat of the high-temperature flue gas for gasification of the raw material, and superheat it across the temperature and send it to the radiation section for thermal cracking; The excess heat is used to preheat the boiler feed water and superheat the high-pressure steam produced by the quench boiler system.

Each set of coils in the convection section of cracking furnace is mainly welded by the heat exchange furnace tube (plain tube or fin tube) through the return elbow group, the end tube plate and the middle tube plate support the furnace tube, and the inlet and outlet of some coils are gathered together through the collecting box. The four sides of each group of coils are then grouped against the furnace wall to form a module.

The function of the quench boiler system is to recover the energy of the high temperature cracking gas leaving the radiation section to produce saturated ultra-high pressure steam. About 42% of the combustion heat provides reaction heat and heating in the radiation section, about 51.5% is recovered in the convection section, about 1.5% is heat loss, and the rest is smoke loss.