Study On The Combustion Of Ethylene Cracking Furnace

The thermal cracking process of ethylene is an important process in the ethylene industry, in which the cracking furnace of ethylene with high-tech is the key unit in the set of ethylene equipments, which is usually of tube frame. Only some foreign corporations hold the whole technique of ethylene production at present. Lacking for the knowledge of hydro-flow, mass transfer and heat transfer in the furnace, it is difficult to get the operation analysis and the furnace design optimization. Thus,it is very significant for us to study details of the combustion reaction and transfer process in the cracking furnace.Computational Fluid Dynamics (CFD) is a new available research method in the chemical reaction engineering field, which takes more important role in the cracking furnace design recently. Now the radiant process in the furnace has been fully stimulated, while the influence of fuel combustion, smoke flow and heat transfer is rarely studied in the simulation. Thus, it is important and necessary to improve the computing model of the furnace combustion.Considering the interaction of the fluid flow, mass transfer and heat transfer, this research chooses non-premixed PDF model, discrete ordinates model, and turbulence k -εcmodel to set up a new model, which is used to simulate the furnace tion process. The simulation results show the distribution of component concentration and temperature and express the interaction of the complicated processes in the furnace. The results are in accordance with the industrial data, which demonstrates the rationality and availability of the furnace combustion model.This research stimulates the velocity field, the concentration field and the temperature field of combustion process with the established model in the SRT-GK-VI thermal cracking furnace of ethylene. The detailed distribution of the velocity, concentration and temperature has been found and the interaction of the flow, mass and heat transfer processes has been acquired, which help us further seize the internal rule of the interaction. The varied operations with different excess air coefficient and different combustion equipment have been stimulated and compared. The comparison describes the influence of the varied operations, which can assist the operation optimization and the design of the cracking furnace.