Physical Modelling On Migration Behavior Of Gas Bubbles In The Metallurgical Melt

As in the process of smelting electric arc furnace dust contains a lot of toxic substances,this dust can cause environmental pollution.regardless of in the process of transportation or piled up in the process of storage.In addition,a lot of positions can produce dust in the electric arc furnace smelting workshop,Numbers of people suffering respiratory disease incidence mills occupy the highest percentage.Choose dust collector and landfill treatment of electric arc furnace dust is unable to avoid or eliminate the generation of dust.In this paper,the mechanism of CO bubble rupture resulting dust generated as the theoretical basis,for the purpose of reduced dust from the sources,a bubble in the melt migration behavior and the influence factors of the splash burst was studied.Providing measures and making theoretical guidance to control dust in the electric arc furnace smelting process.The HX-7 high-speed camera(NAC Japanese company)was used to see movement path of bubbles in the still water and the behavior in slag-liquid interface and liquid slag surface.Quantitative analysis impact of bubbles droplets(dust)content and its shape and others.The research results show that,the bubble behavior on the melt surface main include this: the bubble moves on the surface,bubbles mix together,produce film drop and splash drop.Bubble size increase with the bottom-blowing pore expand,the bubble continuous overturn when it goes up and it movement become more tempestuously with the size increase.In the surface,with the viscosity become higher,the bubble moves longer and it take a long time to burst.When the viscosity become lower,the bubble is instability and easy bursting;with viscosity increase the surface bubble becomes easy to mix together;when it increase more,the bubbles mutual contaction but not mix into one bubble until burst.A proper increase viscosity may prevent splash drop and avoid dust producing.The viscosity of edible oil is low,the bubble takes short time and directly pass the interface of water-oil and take oil a long way,the height is about 41.5mm.The bubble size gets bigger with the diameter of bottom-blowing pore increases but little.the bubble is smaller,the shape is stable and almost become roundness,if the size is bigger,the shape is easier changing.Bubble velocity is direct proportion with radius square root,the average velocity increase little with the radius increase.The distance between collecting equipment and melt surface is over 12 mm,the collecting splash drop content change little with the height increase,maybe because it just absorbs small particles of film drop.It easy causes producing dust with bottom-blowing gas increase.The dust produce hardly in high-viscosity and the dust content decrease with slag get more;The viscosity is lower,the dust content decrease little by little with slag get more in the course of blow open slag surface,but when it can not blow open slag surface,the droplet content increase first and then fluctuate within a certain range.The high-viscosity slag is not easy to be blowing open and avoid steel secondary oxidation.In order to avoid dust produce,the high-viscosity and more slag should be choosed.