| The side-blown submerged combustion bath melting process is an enhanced bath melting process developed independently by China,which has the characteristics of high melting intensity,simple material preparation process,strong material adaptability,high lead output rate and low production cost.However,in the actual melting process,there are some problems such as insufficient penetration depth of jet gas,unsatisfactory velocity field distribution in the melt pool,and violent slag splashing.The side blowing immersion lance is the core equipment of the side blowing pool melting technology,so how to improve the parameters of the side blowing immersion lance to strengthen the side blowing process of gas-liquid momentum transfer process is very important.However,the key characterization parameters of the side-blown melting process are difficult to obtain directly through experiments at present.Thus,this investigation combines the side-blown submerged combustion process and kiln structure,and uses numerical simulation to focus on the variation of the penetration depth of the jet gas under various lance parameters in the lead side-blown bath melting process,analyzes the causes of the slag splashing phenomenon in the melting process under various working conditions and proposes optimization parameters,which provides a theoretical basis and data support for the technical optimization of the lead bath melting process.Firstly,this study coupled VOF multiphase flow model and Realizable k-εturbulence model,and the accuracy of the coupled mathematical model was verified by a self-built water model experimental platform.The results show that the bubble morphology of the coupled mathematical model basically matches with the experimentally obtained bubble morphology when describing three bubble flow states,such as bubble-like flow,slug flow and emulsion flow,which proves that the coupled mathematical model has good accuracy.Secondly,this research takes different lance injection velocity,lance declination angle,gas injection method and lance diameter as the research starting point,and a total of sixteen sets of working conditions are set up to investigate the characteristics of the penetration depth variation of the jet gas in the melt pool.The results show that the penetration depth of the jet gas is mainly affected by the velocity in the horizontal direction.Injection velocity increased from 100m/s to 160m/s,penetration depth increased from 0.485 m to 0.645 m.The penetration depth of the gas is less than the direct flow when using cyclonic flow,but the swirl allows the melt to be stirred by the gas over a larger space at the nozzle.Finally,the effect of lance injection velocity,lance immersion depth and melt pool liquid level height on the melt splash characteristics was studied.The results show that the residual kinetic energy of the bubble cluster while escaping from the melt liquid surface is the main reason for the melt splashing during the side-blow melting process.The growth of the gas injection velocity and the reduction of the melt pool height would both increase the residual kinetic energy of the bubble cluster.When the lance is installed in a non-submerged manner,the splash height is 0.96 m.The upward path of the gas is close to the wall of the melt pool and creates a continuous scouring of the melt pool wall,which consumes a small amount of kinetic energy of the bubble cluster and thus reduces the residual kinetic energy of the bubble cluster when escaping.lance immersion depth increased to 0.12 m,the melt and bubble contact area increased.The melt absorbs a large amount of kinetic energy from the bubble cluster,and the residual kinetic energy when the bubble cluster escapes is reduced,and the melt splash height is reduced to 0.85 m. |
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