Behavior Of Floating And Bursting Of Bubbles In The Metallurgical Melts

In the electric arc furnace steelmaking process,about 20 kg of dust generated per ton steel produced,which would cause potential environment hazardous by stockpile or landfill and high treatment cost.Therefore,it is very meaningful to reduce the production of EAF dust from the sources.The decarburization reaction in the EAF steelmaking process generates large amount of CO gas bubbles.The bursting process of these CO gas bubbles is the major cause of dust.In this paper,the physical modeling and numerical simulation are used to study the behavior of bubbles in the liquid iron.The behavior of single bubble and two bubbles rising in the liquid iron are simulated by VOF model in Fluent 12.0.HX-7 high speed camera is used to record the behavior of single bubble burst and droplet drop at the liquid iron surface.The effects of various factors on the output of dust are studied by physical simulation.The results show that:(1)In numerical simulation,the larger the radius and blowing volume of a single bubble,the faster the average rising speed is,and the temperature has little influence on these two systems.(2)While double bubbles are rising in the molten iron,there is a critical fusion spacing.When the initial spacing is less than the critical fusion spacing,the bubbles will merge,on the contrary,they will not merge.(3)The high-speed cameras could record several kinds of droplets: single droplets,group droplets,large droplets which can be divided to several small droplets,and droplets falling into the liquid iron again in the rising process.(4)The output of dust is positively related to the diameter of bottom hole and the blowing volume,negatively related to the height of collector plate.(5)The diameter distribution of dust particles collected on the collection plate is not uniform.The larger the diameter is,the less the amount of the dust are,on the contrary,the amount of the dust would be more.