Numerical Simulation of Multiphase Flow Behavior in Hot Metal Ladle Desulfurization with Bottom Powder Injection and Electric Field

A computation fluid-coupled discrete phase model (CFD-DPM) was used to predict the motion characteristics of gas, particle, and liquid phases in the hot metal ladle. The influence of different voltage loading modes, voltage values, and powder injection speeds on the particle motion trail was investigated, while the effects on the particle concentration maximum difference in the stagnation region were discussed. The optimal injection and voltage parameters were proposed. The results are shown as follows: the loading voltage before injection is beneficial to the diffusion of particles in the molten pool. With the increase of voltage and injection speed, the distribution of particles in the upper part of the molten iron tends to be uniform. The bottom of the ladle is the stagnation region. Optimum voltage and injection speed were determined. Under the optimum conditions, particles are evenly dispersed and the particle concentration difference in the stagnation region is small. This research work will benefit greatly to the hot metal ladle desulfurization technology.

Influence of clogging of a T-shaped desulfurization lance on the flow field in a hot metal ladle

Lance injected desulphurization become ineffective when injection ports become obstructed. In this work, the difference of the flow fields between single and double hole injection was investigated by numerical simulations. When one of the openings in a T-shaped injection lance is blocked, a dead zone occurs in the ladle over approximately 1/4th of the volume, and there is not an active flow field on the surface of clogging side. To decrease clogging, industrial experiments examining different diameter lances were carried out. The results showed that clogging can be reduced by increasing the injection pressure and optimizing the injection hole diameter to be approximately 10 times the particle size of desulphurizer.

Optimization of Co-Injection Desulfurization of Vanadium Bearing Hot Metal

The desulphurization process parameters of vanadium bearing hot metal were optimized. It is found that it has the best desulfurization effect in 100t hot metal ladle, when the lance position is 280mm, the ratio of lime to Mg is 3:1, and the Mg injection rate is 9kg/min. The Si and Ti content of hot metal can increase the activity of S. With the increase of Si and Ti content of hot metal, the final sulfur content has a reduction trend. When the content of Si and Ti is lower than 0.35%, the final sulfur content of hot metal increases, and the hit rate decreases. The effect of hot metal temperature on desulfurization end point hit rate is obvious. When the hot metal temperature is between 1300~1320°C, the hit rate of desulfurization end point is higher. When the temperature is below 1300°C or above 1320°C, the sulfur content increases. After optimization of process parameters, the Mg and lime consumption per ton of hot iron are reduced by 0.11kg and 0.54kg, respectively, with the average hit rate of desulfurization end point increased by 22.6% and 10.7%, respectively.

Finite Element Analysis Improves Design of Hot Metal Ladle Car

An electric powered Hot Metal Ladle Car was designed to safely transport a ladle filled with 160 metric tons of molten steel. The ladle geometry and space constraints within the use environment were specified. A final design was prepared and documented which met the design requirements and could be efficiently manufactured. An initial design was developed using past designs of a similar nature as a basis. By hand stress calculations were performed and the design modified to get stress values to acceptable levels. Preliminary design drawings were developed. At this stage of the design, some engineering personnel felt that the “by hand” stress analysis was sufBciently accurate to go ahead with fabrication. After much discussion it was decided to perform a Finite Element Analysis (FEA) to verify the design stresses calculated “by hand”. The FEA analysis predicted stresses that were significantly higher than indicated “by hand” in some critical change of section regions. These stress levels were much higher than the allowable stresses for this design. The difference between the FEA stresses and “by hand” stresses were evaluated. After much discussion and thought an insight to the actual load flow was developed which was consistent with the FEA results. With this insight, modifications were made to the design and incorporated into the FEA model. These changes needed to be practical from a manufacturing and end use viewpoint. After a few iterations on the design tire FEA stresses were reduced to an acceptable level. These changes were incorporated into the design. The final design of the ladle car was fabricated. The design was significantly improved due to the ability to accurately calculate stresses in transition regions of the frame where “by hand” methods were not really applicable. The combination of “by hand” methods to ballpark a design and FEA methods to reftne a design proved to be a powerful method to get a truly good design.