32
D. Li et al.
three-dimensional mathematical model of gas–liquid two-phase flow in a bottomblown molten bath by means of numerical simulation. The optimum arrangement of
oxygen lances structure was obtained by taking gas holdup, average melt velocity,
and average turbulent kinetic energy as optimization indexes. Yan et al. [5] studied
the gas–liquid two-phase flow process of a high temperature melt in a bottom-blown
molten bath by numerical simulation, discussed the arrangement of oxygen lance and
the relationship between the diameter of the oxygen lance and the melting process
of molten bath, and obtained the layout and diameter of the oxygen lance under
the optimum melting conditions. Zhang et al. [6] used the Eulerian–Eulerian model
to describe the gas–liquid two-phase flow in the bottom blowing melting bath and
explored the gas–liquid two-phase flow at different injection angles. The simulation
results of flow characteristics and gas content show that the surface splashing of
molten bath is more serious when the oxygen lance angle is 14°. Yu et al. [7] used
the VOF model to explore the relationship between four different nozzle structures
and the mixing area and found that the dispersive nozzle structure is more favorable
for mixing.
The above papers provide many application examples and model calculation methods for the application of numerical simulation in the molten bath, but there is no
in-depth discussion on the oscillation effect, and the content of gas in the molten pool
has a great influence on the chemical reaction in the molten pool, so it is necessary
to further analyze the change rule of gas content. The model of the bottom-blown
smelting furnace is established to simulate the gas–liquid two-phase mixing flow
process in a bottom-blown molten bath, which can visually reproduce the swing
phenomenon during the process of gas jet injection and can monitor and analyze
the disturbance and moment generated in the process, meet the needs of engineering
design, and provide a theoretical basis for the development of new equipment.
Physical Model
Taking a horizontal rotary bottom-blown copper smelting furnace as the research
object, the external diameter of furnace is 5.8 m, the length is 30 m, and the thickness
of furnace body is 0.5 m. The specific structural parameters of the model are shown
in Table 1. The gas inlet is located at the bottom of the furnace with 30 cross-arranged
oxygen lances. The lance pressure is 0.1 Mpa.
Oxygen is ejected from the nozzle of the lances, and multiple jets are ejected to
mix with the surrounding melt. The original static pressure head is transformed into
dynamic pressure head to overcome the resistance of pipeline, spray gun, and melt
so as to form a uniform diffusion zone of gas in the molten bath. The gas trajectory
is controlled by the structure parameters and process parameters of the oxygen lance
and furnace body, so that the diffusion zone has its standardized shape and trajectory,
which is consistent with the geometry of the furnace body. This gives a relatively
uniform diffusion zone, which has no swirl, no splash, and no dead zone.
D. Li et al.
three-dimensional mathematical model of gas–liquid two-phase flow in a bottomblown molten bath by means of numerical simulation. The optimum arrangement of
oxygen lances structure was obtained by taking gas holdup, average melt velocity,
and average turbulent kinetic energy as optimization indexes. Yan et al. [5] studied
the gas–liquid two-phase flow process of a high temperature melt in a bottom-blown
molten bath by numerical simulation, discussed the arrangement of oxygen lance and
the relationship between the diameter of the oxygen lance and the melting process
of molten bath, and obtained the layout and diameter of the oxygen lance under
the optimum melting conditions. Zhang et al. [6] used the Eulerian–Eulerian model
to describe the gas–liquid two-phase flow in the bottom blowing melting bath and
explored the gas–liquid two-phase flow at different injection angles. The simulation
results of flow characteristics and gas content show that the surface splashing of
molten bath is more serious when the oxygen lance angle is 14°. Yu et al. [7] used
the VOF model to explore the relationship between four different nozzle structures
and the mixing area and found that the dispersive nozzle structure is more favorable
for mixing.
The above papers provide many application examples and model calculation methods for the application of numerical simulation in the molten bath, but there is no
in-depth discussion on the oscillation effect, and the content of gas in the molten pool
has a great influence on the chemical reaction in the molten pool, so it is necessary
to further analyze the change rule of gas content. The model of the bottom-blown
smelting furnace is established to simulate the gas–liquid two-phase mixing flow
process in a bottom-blown molten bath, which can visually reproduce the swing
phenomenon during the process of gas jet injection and can monitor and analyze
the disturbance and moment generated in the process, meet the needs of engineering
design, and provide a theoretical basis for the development of new equipment.
Physical Model
Taking a horizontal rotary bottom-blown copper smelting furnace as the research
object, the external diameter of furnace is 5.8 m, the length is 30 m, and the thickness
of furnace body is 0.5 m. The specific structural parameters of the model are shown
in Table 1. The gas inlet is located at the bottom of the furnace with 30 cross-arranged
oxygen lances. The lance pressure is 0.1 Mpa.
Oxygen is ejected from the nozzle of the lances, and multiple jets are ejected to
mix with the surrounding melt. The original static pressure head is transformed into
dynamic pressure head to overcome the resistance of pipeline, spray gun, and melt
so as to form a uniform diffusion zone of gas in the molten bath. The gas trajectory
is controlled by the structure parameters and process parameters of the oxygen lance
and furnace body, so that the diffusion zone has its standardized shape and trajectory,
which is consistent with the geometry of the furnace body. This gives a relatively
uniform diffusion zone, which has no swirl, no splash, and no dead zone.