Effects of the Ultrasound Treatment on Reaction Rates in the RH Processor Water Model System
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Ruhrstahl–Heraeus (RH) processor is widely applied to the refining process to produce steel with very low carbon contents. In this study, to investigate the effect of ultrasound treatment on RH decarburization process, we have developed two kinds of the water models simulated the RH process and study the removal rate of dissolved oxygen. The one is the RH water model of 1/8 size of actual RH degasser simulated the late-stage of the RH process when surface reaction and plume reaction mainly occur. Through this model, it is found that the ultrasound treatment accelerates dissolved oxygen removal reaction and this tendency is maintained even at low concentrations. Also, the results show that there is a difference in the degassing efficiency depending on the frequencies and the positions of the ultrasonic transducer. Also, to simulate the Early-stage Reaction of the process including the inner-site reaction which is difficult to investigate through the RH water model, the other water model has been developed (the RH-ER water model). This model shows that the ultrasound treatment facilitates the early-stage reaction including inner-site reaction, like the RH water model. These results show that the addition of the ultrasound treatment can accelerate decarburization reaction during RH process compared to conventional process.
KeywordsMetals RH degassing Water model experiment Ultrasonics
The authors would like to express their gratitude to the Center for Iron and Steel Research at Research Institute of Advanced Materials (RIAM) in Seoul National University for their financial support of this work.
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