The Ways To Improve The Dust-catching Rate Of The BF Gas Gravity Duster

In this paper, it has been discussed that several familiar blast furnace (BF) gas dust-catching systems at home and abroad and dust-catch technology. A series of reforming projects to the present gravity duster are developed because that the dust-catching rate of the present gravity duster is lower and tested in laboratory. On the base of FLUENT software numerical simulating the flow disciplinarian of gas and grain in the dusters and combining the theory of dust-catching, the reasons that reform projects can increase dust catch rate are analyzed.The basic idea of the first reforming project is to change the position of gas entering. The BF gas enters into the gravity duster from the two pipes on the top cone, and then comes out from center pipe. Results of experiment show that dust-catch rate can be increased obviously. The reasons are: in tradition duster, grain separate with gas depend on gravity sedimentation and change direction of gas, the dust-catch rate is lower. After changing the position of entering gas, two section airflow enter from cone wall. The airflow strike center export gas pipe and form four section revolve airflow, when they barge up against the opposite airflows, form new airflows. In the end, they were piped out from center export gas pipe. Because change airflow's walk path, added the action of inertia dust-catching and whirlwind dust-catching.The basic idea of the second reforming project is: on the basis of the first project, add two revolving-flow boards at two gas entering pipes, if the angel of revolving-flow boards is reasonable, the dust-catching rate can be improved more than 90%. The reason is: the airflow keep revolving when it enter the duster, the action of whirlwind dust-catching get bigger.The basic idea of the third reforming project is: a baffle with a cone angle of 45° was added to a suitable position of the gravity duster. Experiment proves, the dust-catching rate was decreased. The reason is the baffle can depress the airflow quantity of entering the bottom of the duster, the amount of aggradation dust that was turned up decreased.