Marangoni flows and corrosion of refractory walls

Abstract

Local corrosion of a refractory at slag-gas and slag-metal interfaces is caused by the active motion of slag film formed by the wettability between the refractory and slag. In the systems of SiO 2 (s)-(PbO-SiO 2 ) slag and SiO 2 (s)-Pb(l)-(PbO-SiO 2 ) slag, where components from the refractory dissolve into the slag increasing the interfacial tension of the slag or slag-metal, continuous washing of the refractory wall with thin fresh slag film supplied from the bulk slag phase by the Marangoni effect causes the local corrosion of the refractory above the slag level or below the metal level. When the dissolved component from the refractory reduces interfacial tension, for example, in the system of SiO 2 (s)-(Fe t O-SiO 2 ) slag, the local corrosion is induced by the active slag-film motion with alternative formation and disappearance in cyclic mode due to the Marangoni effect, and changes in the form of slag film due to the variation of interfacial tension and density of the slag film. Local corrosion of oxide refractories for practical use, containing trough materials, at slag-gas and slag-metal interfaces is classified into the above two types. The Maragoni flow of the slag film is also considered to play an important role in the local corrosion of oxide-graphite refractories such as Al 2 O 3 -C and MgO-C at the slag-metal interface during the stage of the oxide phase corrosion in the refractory.

Comparative study of oxide inclusion dissolution in CaO–SiO2–Al2O3slag

“…It is likely that the inclusion rotation is due to Marangoni (interfacial tension driven) flow. 31 Marangoni flow can be described by…”

Escoamento De Ferro-Gusa Em Canal De Alto-Forno E Sua Relação Com O Desgaste Do Revestimento Refratário

“…Já a tubulência mais intensa aprimora esta mistura entre as fases. É sabido que ocorrem diversas reações químicas entre o refratário, metal, o ar,e a escória (Mukai, 1998;Mukai, et al, 1989), e a presença de ar e a mistura aprimorada pelas flutuações de velocidade turbulenta, associadas a uma tensão cisalhante oscilante podem então promover a corrosão, dissolução e abrasão do refratário.…”

Dissolution behavior of zirconia-refractories during continuous casting of steel

“…If SEN cannot withstand thermal shock or corrosion attack from the liquid steel and molten flux, the quality of the steel products will be deteriorated or the casting process may fail [1][2][3][4]. While the use of stabilized ZrO 2 -graphite at the SEN provides better corrosion resistance, it is also attacked by the mold flux and liquid steel.…”