基于废槽衬的有害性,以无害化处理为目的,考察了石灰改性废槽衬对氟化物的固化效果,对改性前后废槽衬用作砂浆掺合料的可行性进行了分析.结果显示:石灰改性废槽衬经980℃的高温煅烧,可有效地固化氟离子,固化率达到90%以上;在同等掺量条件下,改性后废槽衬用作掺合料较改性前废槽衬用作掺合料制备的砂浆28 d的强度提升了30%~50%,且试件氟离子浸出安全性符合国家标准;从砂浆的整体强度上看,废槽衬掺合量以低于10%为宜.
In view of the harmfulness of spent potliner,and with the aim of pollution-free disposal,the fluorine reten-tion effect of spent potliner by lime modification is investigated,and modified spent potliner as mortar admixture is analyzed in this paper.The results show that through calcining the spent potliner by lime modification at 980 ℃,solu-ble F-is effectively transferred into stable fluorides,with the solidification ratio of 90%.At the same dosage,the 28 d strength of mortar using modified spent potliner as admixture increases by 30%~50% more than that of the mortar in spent potliner before modification,and the fluoride leaching of mortar satisfies national safety standard.The results also reveal that the content of modified spent potliner within 10% is appropriate when used as mortar admixture.