稀土粉尘对粉煤灰节能制品的绿色效应研究

STUDY OF GREEN EFFECT OF RARE EARTH DUST ON ENERGY SAVING PRODUCT OF FLYASH

粉煤灰节能制品是指经常压养护的多孔粉煤灰制品 ,它具有优良的胶凝性、节省资源能源、高效节能、符合可持续发展战略 ;但因其收缩大 ,影响推广应用。当掺入稀土粉尘 (XF) 7%时则产生显著的绿色效应 :不仅抗压强度提高 49%～ 88% ,而且各龄期干缩值减小 ,极限干缩率减小 18%。通过化学分析和扫描电镜形貌观察证明 :增强和减缩机理主要是由于XF的微粉作用、其化学组成与粉煤灰胶结料中的Ca(OH) 2 反应 ,生成不溶于水的C—S—H凝胶、生成强度高且微膨胀的E盐所致。

An energy saving product of the flyash is the one that is cured at normal pressure and with cellular structure.It has a fine gelatinuos property.saves natural resources,economizes energy resources and is in keeping with sustained developmental strategy.However,because of its larger shrinkage that affects its spread and application.Starting from the study of shrinkage mechanism in this paper,when 7% of rare earth dust(XF) was added,remarkable green effect was produced;not only 49%～88% of the compressive strength was increased but dry shrinkage value for every age was decreased also,and the ultimate rate of dry shrinkage decreasing by 18%.By chemical analysis and SEM observation,it is shown that the mechanism of strengthening and shrinkage decreasing is mainly due to the action of XF dust,being the result of the chemical composition of XF dust reacting with Ca(OH) 2 from flyash cementing materials to form,C-S-H gel not solvable in water and E salt with a high strength and a micro expansion