Effects of the Ultrasound Treatment on Reaction Rates in the RH Processor Water Model System

다국어 초록 (Multilingual Abstract)

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 ofthe water models simulated the RH process and study the removal rate of dissolved oxygen. The one is the RH water modelof 1/8 size of actual RH degasser simulated the late-stage of the RH process when surface reaction and plume reaction mainlyoccur. Through this model, it is found that the ultrasound treatment accelerates dissolved oxygen removal reaction and thistendency is maintained even at low concentrations. Also, the results show that there is a difference in the degassing efficiencydepending on the frequencies and the positions of the ultrasonic transducer. Also, to simulate the Early-stage Reaction ofthe process including the inner-site reaction which is difficult to investigate through the RH water model, the other watermodel has been developed (the RH-ER water model). This model shows that the ultrasound treatment facilitates the earlystagereaction including inner-site reaction, like the RH water model. These results show that the addition of the ultrasoundtreatment can accelerate decarburization reaction during RH process compared to conventional process.

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