Research On Doping Effect And Solidification Of Heavy Metal Ion In Cement Clinker

This eassy is based on State support arranged project(2006BAF02A24)and Hubei province science and technology project,by means of burnability analysis, physics mechanics performance test,chemical analysis,XRD,SEM and high temperature micro analysis,discuss the effect mechanism of burnability,Lithofacies photo performance,grain size,mineral match- ing,clinker performance when adding heavy metal ion.So to evaluate the domino effect of heavy metal ion.Ion pauling radius is used as the research masterstroke,sum up the relation between ion pauling radius and the above guide lines,and farther to analyse relation in lithofacies photo performance,grain size and clinker performance.Besides,EDS analysis is used to construe the solidify content of Mn⁴⁺,V⁵⁺,Ni³⁺,Co³⁺,Cr³⁺in the C₃S,C₂S and intermediate phase,primariliy discuss the solidify behavior and mechanism of heavy metal ion.The research results indicate,The burnability,lithofacies photo performance, similar calcium or silicon and stabilization on the crystal lattice of various metal ion oxide(MnO₂,V₂O₅,Ni₂O₃,CO₂O₃,Cr₂O₃,CuO,SnO₂,ZnO)are correlative with ion electrovalence configuration,electronegativity,acidity and alkalescence. Combine high temperature micro analysis to know:At low temperature,the effect of lithofacies photo performance which heavy metal ion affect is more important;at high temperature,substitute calcium or silicon from mineral which make absorbing f-CaO easy or difficult.Make Ni or Co as cut-off point,when at low temperature,MnO₂,V₂O₅,Ni₂O₃ do bad for the lithofacies photo performance,and farther to affect burnability,mineral index point, and also because the solidify effect of Mn⁴⁺,Ni³⁺at high temperature is to change the reaction balance.And V₂O₅ stableβ-C₂S,also change the reaction.The radius of Co³⁺is between Si⁴⁺and Ca^2-,so either at low or high temperature,Co³⁺takes up important role at lithofacies photo performance in the clinker,the solidify domino effect is not so much obvious.Cr₂O₃,CuO,SnO₂,ZnO do better for he lithofacies photo performance,and farther to promote burnability,mineral formation,but the stability of Cr₂O₃ to reduce the grow content of C₂S,at the same time,because of the solidify effect of Cu²⁺,Sn⁴⁺in the clinker to change saturation ratio which let the burnability break,so the burn- ability weaken when CuO,SnO₂,ZnO adding, and also there is relation between lithofacies photo performance and grain size.Sparse heavy metal element do as mineralizer at solidify feedback,to change physics character of intermediate phase at high temperature,such as viscosity and surface tension ect.And also such heavy metal ion give various defect and change configuration of melt and crystal or react with OH to create deposit,restrain the hydration,so to change the crystal configuration of silicate mineral and hydration activity,especially the effect of Zn and Cu on the restraining the hydration. Use SEM-EDS analysis,we can know:when adding heavy metal ion,they can solidify some contently in the mineral.The radius of V⁵⁺,Ni³⁺,Co³⁺,Cr³⁺are 115% times as that of Fe³⁺,in theology,they can substitute Fe³⁺,especially Ni³⁺and Co³⁺ react in the C₄AF,the content of C₄AF is more when adding.The Pauling radius of Mn⁴⁺,V⁵⁺,Ni³⁺,Co³⁺and Cr³⁺is greater than that of Ca²⁺by 15%,if can not substitute,it can gap-fill in the inanition.Some data show that,Mn⁴⁺,Ni³⁺,Co³⁺can easily solidify in the C₃S,and because of this behavior,it bring about unbalance of charge or vacancy defect,these defects bring about great effect on mineral performance.And V⁵⁺and Cr³⁺can easily solidify in theβ-C₂S,and it can restrain the move at the new interface,so can control the C₂S grain size.