Study On Blast Circumferential Uniformity Of Large Blast Furnace

In a long time,oxygen enriched blast furnace has been applied as a practical operation in Chinese iron and steel enterprises,and has effectively improved the smelting strength and production efficiency of blast furnace.In the blast process,the hot air flows into the coaming pipe and into the branch pipe for redistribution,so as to ensure the uniform distribution of oxygen-rich air is an important work in the smelting process,which not only affects the forward flow of the blast furnace,but also affects the size and shape of the blast furnace tuyere roundabout area,and then affects the fluid movement in the furnace cylinder and the structure of the charge.Due to the large structure of the confining pipe and the complex process of gas flow in the confining pipe,the morphologic characteristics,dynamics and thermodynamic behaviors of the blast furnace roundabout zone have been the focus of research at home and abroad.In this thesis,the model is constructed according to the real data of the 4038 m~3 blast furnace of A steel mill,and the air volume of the single pipe and the whole air supply pipe are simulated respectively.Then,the ANSYS Fluent software is used to simulate the parameters such as wind pressure and wind speed,so as to explore the law of air volume distribution.In this thesis,based on the actual drawings of 4038m~3 large blast furnace of A steel mill,as the standard,Solid Works software is used to model the blast furnace body air supply system,and the theoretical calculation results are compared,and the theoretical calculation of energy loss in the process of air supply is proposed.Then Fluent software was used to conduct numerical simulation of unadjusted parameters,blockage of some tuyere in different positions and reduction of some tuyere,to explore the influence of adjusting some parameters on the overall blast situation.The conclusion show that the air volume of tuyere is positively correlated with the air pressure at the junction of supply pipe and branch pipe.When part of the tuyere is blocked,the air volume of the remaining tuyere is increased as a whole,with an increase of about 9.09%.However,when the tuyere is blocked,the variance of the unblocked tuyere is 1%～2%,with a small range.Therefore,the blocked tuyere has little influence on the blast structure and the symmetry of air volume distribution.When part of the tuyere is reduced,the air volume of the tuyere is reduced by about20%～25%,and the distribution uniformity of the overall air volume is decreased.For the tuyere that is not blocked,the average air volume is increased by about 2.08%.When the air volume is increased,the uniformity of the air blast is also improved according to the different positions of the adjusted tuyere.