The Role of the Size Effect on the Drying of Refractory Castables—How Its Under-standing Could Narrow the Gap between Laboratory Studies and Industrial Reality  

作　　者：M.H.MOREIRA H.PENG S.Dal PONT V.C.PANDOLFELLI 

机构地区：[1]Materials Engineering Department,Federal University of São Carlos(UFSCar),São Carlos 13565-905,Brazil [2]Materials Innovation,Elkem Silicon Products Development,Kristiansand 4621,Norway [3]CNRS,Grenoble INP,3SR,UniversitéGrenoble Alpes,Grenoble 38000,France

出　　处：《China's Refractories》2024年第2期35-40,共6页中国耐火材料（英文版）

基　　金：the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001.The authors would like to thank the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP(grant number:2021/00251-0).Finally,the authors are also greatly thankful for FIRE support to carry out this work.

摘　　要：Refractories have unique capabilities such as sustaining their shape and properties at extreme conditions such as the combination of high temperatures and thermal shock,contact with molten metals and slags and in some circumstances resistance to erosion from abrasive particles.Given the large processing output of the heavy industries such as the cement and steel ones which both require high temperature processes,the refractories structures span various meters and weight of several tons.As the water removal stage of hydraulic bonded castables in industrial sites takes hours(10-60 h)due to the risk of explosive spalling,efforts to mitigate it are commonly studied.This has provided theoretical understanding of the general aspects of drying and important tools,such as the thermogravimetry analysis(TGA),for the design of refractory compositions with higher explosive spalling resistance.However,the optimization of this process is still far from the industrial reality especially because the actual linings that require the drying are orders of magnitude larger than the samples considered in the laboratory tests.Therefore,this study proposed the analysis of the sample volume effect on the water removal dynamics through TGA of high alumina castables with calcium aluminate cement.Conventionalφ5 cm×5 cm cylindrical samples were assessed in a laboratory scale equipment whereas macro TGA were carried out considering 20 cm×20 cm×20 cm and 30 cm×30 cm×30 cm cubic samples.Additionally,the effect of polymeric fibers was also considered.It was found out that the different thermal gradients within the macro TGA samples resulted in an inflection on the sample’s heating rate and that the mass loss was affected by the volume considered,especially for the composition without additives.These findings highlight the requirement of carefully taking into consideration the different dimensional sizes and thermal gradients in the samples when analyzing and interpreting the laboratory studies,and especially when trying to extrapolate su

关 键 词：DRYING refractory castables size effect thermogravimetry analysis 

分 类 号：TQ175.732[化学工程—硅酸盐工业]