Kinetics of Coper Evaporation from the Fe-Cu Alloys Under Reduced Pressure

Abstract

This paper provides an analysis of the results of studies concerning the impact of pressure on the process of copper removal from liquid ferrous alloys by evaporation. The research was conducted in vacuum induction furnace. Iron alloys with 0.509 to 1.518 %wt. Cu content were used for the tests. Kinetics analysis of the examined process was performed for the obtained results and the Speed of the process partial stages was estimated.Keywords: iron alloys, evaporation, vacuum, mass transfer coefficient W prezentowanej pracy przedstawiono wyniki badań nad możliwością usuwania miedzi z ciekłego żelaza na drodze odparowania. Badania realizowano w indukcyjnym piecu próżniowym. Wykorzystano stopy żelaza zawierające od 0.509 do 1.518% mas. Cu. Dla uzyskanych wyników przeprowadzono analizę kinetyczną badanego procesu i oszacowano szybkości jego etapów cząstkowych.

Zero CO2 steelmaking in a future low carbon economy. 2. Secondary steelmaking using refined iron slab, with clean and contaminated scrap

“…A similar equation is applicable to evaporation of copper from alloys with liquid iron. As reported (Labaj 2012) for pressures 100 Pa for vacuum induction refining, the gas phase mass contributes at least 70% of the process resistance. For pressures of 10 Pa and below, liquid phase mass transfer dominates the diffusional resistance but even at 0.06 Pa, the liquid phase resistance represents about 85%of the combined diffusional resistance but is still comparable to the interfacial vaporisation resistance in batch vacuum induction refining.…”

“…A similar equation is applicable to evaporation of copper from alloys with liquid iron. As reported (Labaj 2012) for pressures 100 Pa for vacuum induction refining, the gas phase mass contributes at least 70% of the process resistance.…”

“…An example will now be given to exemplify the advantage of a shift to turbulent open channel melt circulation continuous vacuum evaporation, as in the VDZ process. A value 135.8 × 10 −6 ms −1 for the interfacial vaporisation rate coefficient for Cu evaporation from a particular Cu-Fe alloy at 1659°C has been published (Labaj 2012). Using Equation (2) (Komori et al 1982) and highlighted in Part 1, a liquid phase mass transfer coefficient of 164 × 10 −6 ms −1 is representative of Cu-Fe alloy turbulent flow for 2M tpa in a channel 1.5 m wide × 0.016 m deep.…”

Verification of Possibility of Molten Steels Decopperization with ZnAl2O4

“…In the present investigation, copper was mainly decreased due to its high evaporation rate. According to the literature related to the copper evaporation [10,[26][27][28][29], the copper evaporation process from liquid iron can be divided into three main stages: (1) copper transfer from the bulk of the liquid phase to the interface; (2) copper evaporation from the liquid metal surface; (3) transfer of the copper vapours from the interface to the core of the gaseous phase, as illustrated in Figure 8.…”

Evaporation of the tramp element antimony from molten steel under reduced pressure treatment

“…Nowadays, with the increasing content of tramp elements in steel scrap, some researchers have been drawn to how to remove them from molten steel and have proposed some removal methods, such as the melt filtering process [11,12], calcium reaction process [13][14][15][16][17], sulphide flux treatment [18][19][20][21][22][23] and vapour pressure process [24][25][26]. Nevertheless, most of the studies mainly focus on the removal of Cu and Sn because their content in steel scrap is particularly prominent.…”