摘要
针对大宗工业固废回收利用难的问题,实现多种固废减量化、无害化、资源化的目标,通过利用取自中国西南地区企业的石膏类、碱性及硅铝质三类典型大宗固废中的电解锰渣、赤泥、粉煤灰协同处理的无害化渣制备环保型透水混凝土路面砖(permeable concrete paving bricks,PCB),研究了水洗、掺渣量对所制备PCB的力学性能与浸出毒性的影响,并通过X射线衍射(XRD)和扫描电子显微镜(SEM)对最佳性能PCB的物相组成与微观形貌结构进行分析.结果表明:①随着无害化渣与水洗无害化渣掺入量的提升,路面砖的劈裂抗拉强度、线性破坏荷载发生明显变化,总体呈下降趋势.当无害化渣掺入量为6%、水洗无害化渣掺入量为14%时,经28 d养护,所制备砖体的劈裂抗拉强度分别为4.09和3.46 MPa,达到了《透水路面砖和透水路面板》(GB/T 25993-2010)中规定的f_(ts)4.0与f_(ts)3.0等级.②路面砖的重金属与NH_(4)^(+)-N的浸出毒性均低于《水泥窑协同处置固体废物技术规范》(GB 30760-2014)的要求.路面砖的主要物相中方解石、石英与钙矾石是主要支撑性物质.研究显示,电解锰渣、赤泥、粉煤灰协同处理的无害化渣可替代部分原材料制备透水混凝土路面砖,满足力学性能与浸出毒性相关标准,能有效促进固体废弃物的减量化与资源化,建议进一步开展砖体在实际应用场景中的环境风险试验,以期为电解锰渣、赤泥、粉煤灰的综合利用技术发展提供更明确的支撑.
In response to the problem of difficult in recycling and using bulk industrial solid waste,various goals of solid waste reduction,harmless treatment,and resource utilization have been achieved.An environmentally friendly permeable concrete paving bricks(PCB)were prepared using the harmless treatment slag of electrolytic manganese residue,red mud,and coal fly ash from three typical types of bulk solid wastes of gypsum,alkaline,and silicoalumina from enterprises in southwestern China.The effects of water washing and slag content on the mechanical properties and leaching toxicity of the prepared PCB was studied,and the phase composition and microstructure of the optimal performance PCB were analyzed by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results show that:(1)As the amount of harmless slag and water washed harmless slag increases,the splitting tensile strength and linear failure load of road bricks change significantly,showing an overall decreasing trend.When the amount of harmless slag added is 6%and water washed harmless slag added is 14%,after 28 days of curing,the splitting tensile strength of the prepared bricks is 4.09 MPa and 3.46 MPa,respectively,reaching the f_(ts)4.0 and f_(ts)3.0 levels specified in Permeable Paving Bricks&Permeable Paving Flags(GB/T 25993-2010).(2)The leaching toxicity of heavy metals and NH_(4)^(+)-N in road bricks is lower than the relevant requirements in the Technical Specification for Coprocessing of Solid Waste in Cement Kiln(GB 30760-2014).The main supporting substances of pavement bricks are calcite,quartz,and ettringite.The research shows that the harmless slag obtained by the collaborative treatment of electrolytic manganese residue,red mud,and coal fly ash can replace some raw materials to prepare permeable concrete paving bricks,meet the relevant standards of mechanical properties and leaching toxicity,and effectively promote the reduction and resource utilization of solid waste.It is recommended to further conduct environmental risk tests on the bricks in actual application scenarios to provide clearer support for the comprehensive utilization technology development of electrolytic manganese slag,red mud,and coal fly ash.
作者
白月娇
林晔
孟棒棒
岳波
梁宇廷
BAI Yuejiao;LIN Ye;MENG Bangbang;YUE Bo;LIANG Yuting(School of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang 110168,China;Research Institute of Solid Waste Management,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2024年第2期388-396,共9页
Research of Environmental Sciences
基金
贵州省科技计划项目(No.黔科合重大专项[2022]002)
贵州省交通运输厅科技项目(No.2021-122-005)。
关键词
电解锰渣
赤泥
粉煤灰
透水混凝土路面砖
资源化利用
electrolytic manganese residue
red mud
coal fly ash
permeable concrete paving bricks
resource utilization
