Design of Hollow Cone Nozzles for Gas Oil Injection Process

In the oil refinement industry, one of the most important challenges in the development of fluid catalytic cracking process (FCC), is to increase the evaporation of the gas oil through the contact with the catalytic material. This increase has the special purpose of reducing the production of light gases and coke and increasing the conversion of this hydrocarbon to more selective products like the high-octane gasoline and the diesel oil. In order to obtain the total evaporation of the gas oil, it is required a process of atomization to produce small drops and a system that disperse it in uniform form within the reactor. The objective of the present work is the design of a nozzle that makes these two functions. Some relevant parameters in the design of sprays for systems of gas oil feeding are analyzed to FCC processes and it is presented the case of a circular type nozzle that generates a hollow cone film that has a uniform mass distribution. A model based on a column fluid was used where the fluid forms a conical film which becomes gradually thinner as the liquid film moves away from the nozzle. A theoretical method is discussed to predict the thickness of the film as well as the breakup point. Finally qualitative results of the characterization of spray obtained from experimental visualizations are presented.