摘要
采用浸没式燃烧工艺处理生活垃圾填埋场渗滤液产生的浓缩液污泥副产物具有高易溶盐含量的特征。分别采用硫铝酸盐水泥和碱激发矿粉胶凝材料固化浓缩液污泥,对固化试样进行一系列无侧限抗压强度(UCS)试验、水稳定性试验和微观观测试验,分析硫铝酸盐水泥和碱激发矿粉胶凝材料对浓缩液污泥的固化效果和固化机理。研究结果表明:40%水泥掺量的固化试样的28 d无侧限抗压强度为1.95 MPa,浸水28 d后降低至零。30%矿粉掺量的固化试样的28 d无侧限抗压强度为14.8 MPa,浸水28 d后,仍达3.6 MPa,远大于垃圾填埋场的填埋强度要求。碱激发矿粉反应生成的三维网状胶凝材料和钙矾石晶体可对浓缩液污泥颗粒实现有效的包裹和胶结,是碱激发矿粉胶凝材料固化浓缩液污泥的微观固化机制。
The concentrated solution sludge(CSS)produced by submerged combustion process on leachate has the characteristic of high soluble salt content.The sulfoaluminate cement(SAC)and alkali-activated GGBS geopolymer are used to solidify the CSS,respectively.A series of unconfined compressive strength(UCS)tests,water stability tests and microscopic observation tests are carried out on the solidified samples to investigate the curing effects and curing mechanisms of the SAC and alkali-activated GGBS geopolymer on the CSS.The results show that the UCS of the solidified sample with the SAC of 40%is 1.95 MPa at 28 d-curing age,and decreases to zero after 28 d-water immersion.The UCS of the solidified sample with the GGBS of 30%is 14.8 MPa at 28 d-curing age,and remains 3.6 MPa after 28 d-water immersion,which is much higher than the strength requirement of landfills.The three-dimensional geopolymeric gels and ettringite crystals produced by the GGBS geopolymerization are capable of effectively encapsulating and cementing the CSS particles,which is the curing mechanism of the alkali-activated GGBS-solidified CSS.
作者
冯德銮
王杰
王羽心
陈志城
梁仕华
FENG Deluan;WANG Jie;WANG Yuxin;CHEN Zhicheng;LIANG Shihua(School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou 510006,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2024年第9期1860-1869,共10页
Chinese Journal of Geotechnical Engineering
关键词
浓缩液污泥
硫铝酸盐水泥
碱激发矿粉
水稳定性
固化机理
concentrated solution sludge
sulfoaluminate cement
alkali-activated GGBS
water stability
curing mechanism
