Optimisation of dual purging location for better mixing in ladle: a water model study

Abstract

Mixing time studies were performed on a one-fifth scale aqueous model of a single tapered ladle with different bottom purging locations. Two porous plugs were used simultaneously to purge compressed air as an analogue to argon and this was referred as dual purging. KCl solution (1 N) was used as the tracer for measuring mixing time. The scaled down gas flowrate varied from 10 to 80 L m 21 . Around 400 experiments were done including all possible dual purging locations and the location which gives least mixing time was identified. The results were compared with corresponding single purging experiments and it was found that dual purging can reduce mixing time to a great extent even in the lower flowrate range and a location better than ¡R/2 has been suggested. Effect of differential flow on mixing time has also been reported.

Effect of Differentiated Injection Ratio, Gas Flow Rate, and Slag Thickness on Mixing Time and Open Eye Area in Gas-Stirred Ladle Assisted by Physical Modeling

“…Although efforts have been made to optimize the operation of the ladle, in most cases only the minimization of mixing time is considered and the optimization is not performed using formal algorithms [16][17][18][19]. Recently, Mazumdar et al [11] and Jardón-Pérez et al [20] performed optimizations of mixing time and slag eye area in physical models of a ladle using formal algorithms.…”

Effect of Separation Angle and Nozzle Radial Position on Mixing Time in Ladles with Two Nozzles

“…Most of the previous investigations involving mixing phenomena indicate that mixing time increases due to the presence of the top slag layer. (Kim and Fruehan, 1987;Joo and Guthrie, 1992;Zhu et al, 1995;Jauhiainen et al, 2001;Chiapparoli et al, 2003;Chen et al, 2007;Chattopadhyay et al, 2009;Geng, et al, 2010;Liu et al, 2011;Lou and Zhu, 2014;Patil et al, 2010;Haida et al, 1983;Ying et al, 1983;Yamashita et al, 2003;Mazumdar and Kumar, 2004). The explanation is due to energy consumed to stir the slag and formation of the spout.…”

“…The benefits of this configuration compared with the original design (90 degrees and asymmetric position at 0.67R and 0.79R) reported shorter mixing times in the water model and slightly better desulfurization rates in plant trials. Chattopadhyay et al (2009) included symmetric and asymmetric nozzle positions and three separation angles. In general, the shortest mixing time was achieved with a separation angle of 135 degrees and the two nozzles placed asymmetrically, 0.75R and 0.25R, however, at high gas flow rates the symmetric position at 0.5R and a separation angle of 180ºC reported not only a shorter mixing time but also less erosion of the refractory.…”

Physical Simulation of Molten Steel Homogenization and Slag Entrapment in Argon Blown Ladle

“…Some researchers found that eccentric bottom blowing is in favor of bath mixing in the ladle [7,10]. Some investigators also found that the position of porous plugs, gas flow rate and the size of ladle have an abundant influence on bath mixing in the ladle [4,5,[11][12][13][14][15][16][17]. It was discovered that the top slag layer could consume some part of kinetic energy of flow and enlarge the mixing time of the ladle [18][19][20][21][22].…”