摘要
在研究水玻璃模数、水玻璃添加量、偏高岭土掺量对固硫灰基地聚合物抗压强度影响的基础上,进一步探讨了固硫灰基地聚合物固化含铬污泥的性能及机制。固硫灰制备地聚合物的优化实验参数为:水玻璃模数M为2.5,水玻璃掺比为33.3%,偏高岭土掺比为20%。含铬污泥最大固化量为52%,固化体28 d抗压强度达到6.5 MPa,总铬及Cr(VI)浸出量分别为0.37 mg/L和5.93×10-3 mg/L,远低于GB 5085.3-2007标准限值。XRD和SEM/EDS分析表明含铬污泥及其固化体均为无定形态,污泥中的铬可能以物理包裹的形式被固化于地聚合物凝胶相中。IR分析表明铬元素可能通过化学键的形式进入地聚合物的三维网络结构实现固化。
The effects of modulus and quantity of sodium silicate, content of metakaolinite on the compressive strength of CFBC ash-based geopolymer was explored. At the same time, the property and mechanism of geopolymer solidifying chromium in sludge was investigated. That the modulus of sodium silicate was 2.5, quantity of sodium silicate was 33.3% and content of metakaolinite was 20% were the optimum parameters to prepare CFBC ash-based geopolymer. The content of sludge in solidified body was up to 52% and the compressive strength of solidified body which had been cured under normal temperature up to 6.5 MPa eventually. At the same time the leaching amount of total chromium and hexavalent chromium were far below the national standard value(GB 5085.3-2007). XRD and SEM/EDS analysis showed that the sludge and its solidified body were amorphous. The chromium in sludge might be physical encapsulated in the amorphous geopolymer gel. Iinfrared spectrometry(IR) indicated that chromium may be cured through going into the three-dimensional network structure as chemical bonds.
出处
《非金属矿》
CAS
CSCD
北大核心
2014年第6期66-69,共4页
Non-Metallic Mines
基金
国家自然科学基金(51274262)
煤矿灾害动力学与控制国家重点实验室开放基金(12zs0104)
四川省科技创新苗子项目(13zd3132)
四川省教育厅青年基金(13ZB0183)
关键词
固硫灰
地聚合物
铬
污泥
固化
CFBC ash
geopolymer
chromium
sludge
immobilization