摘要
用不锈钢渣、水泥、粉煤灰、发泡剂与水制备不锈钢渣泡沫混凝土,测试了不锈钢渣及泡沫混凝土的化学成分、微观形貌、矿物组成、结构、游离CaO含量、易磨性、内辐射指数与外辐射指数、活性指数、主要性能指标(抗压强度、干密度和导热系数)和浸出液中重金属浓度,研究了不锈钢渣用于制备泡沫混凝土的可行性与环境风险。结果表明,不锈钢渣的主要矿物组成为Ca2SiO4及含Al和Ti, Cu, Pb, Ta等重金属的矿相,具有一定胶凝活性且易磨,内辐射指数与外辐射指数满足建筑材料放射性元素限量要求。不锈钢渣掺量为25wt%42wt%时,泡沫混凝土的干密度为597621 g/cm3,养护28 d后抗压强度为1.832.98MPa、导热系数为0.110.12 W/(m×K),满足泡沫混凝土要求。不锈钢渣所含重金属主要以稳定的金属固熔体存在,浸出浓度远低于危险废物限值。
Stainless steel slag foam concrete was prepared using the stainless steel slag,cement, fly ash, foaming agent and water as raw materials. Chemical composition, micro morphology, mineral composition,structural, free CaO content, grindability,internal exposure index and external exposure index, activity index of the stainless steel slag and foam concrete were tested. In addition, the main performance parameters of the prepared foam concrete,such as compressive strength, dry density and heat conduction coefficient, leaching concentration of heavy metals were also studied. The results showed that the stainless steel slag had certain cementitious activity and good grindability owing to mineral composition of Ca2SiO4. The internal exposure index and external exposure index of the foam concrete satisfied the requirements of the limits of radionuclides in building materials, although it contained Al and heavy metals of Ti, Cu, Pb, Ta, etc. The dry density was 597621 g/cm3, compressive strength was 1.832.98 MPa after curing 28 d and heat conduction coefficient was 0.110.12 W/(m×K), which satisfied the requirements of foam concrete, when 25 wt%42 wt% stainless steel slag was used in the foam concrete. The main heavy metals in the stainless steel slag mainly existed as stable solid metals. The leaching concentration of heavy metals from the foam concrete was much lower than the limit value of the identification standards for hazardous wastes. Therefore, it was safe and feasible to utilize the stainless steel slag to produce foam concrete.
作者
张浩
陈华
张磊
刘秀玉
Hao ZHANG;Hua CHEN;Lei ZHANG;Xiuyu LIU(School of Civil Engineering and Architecture,Anhui University of Technology,Ma'anshan,Anhui 243032,China;College of Materials Science and Engineering,Xi'an University of Archiecture and Technology,Xi'an,Shaanxi 710055,China;Key Laboratory of Metallurgical Emission Reduction and Resources Recycling,Anhui University of Technology,Ministry of Education,Ma'anshan,Anhui 243002,China;MCC Baosteel Technology Services Co.,Ltd,Shanghai 201999,China)
出处
《过程工程学报》
CAS
CSCD
北大核心
2020年第3期347-353,共7页
The Chinese Journal of Process Engineering
基金
中国博士后科学基金资助项目(编号:2017M612051)
高校优秀青年骨干人才国外访学研修项目(编号:gxgwfx2018021)
安徽省博士后研究人员科研活动经费资助项目(编号:2017B168)
国家级大学生创新创业训练计划项目(编号:201810360072)。
关键词
不锈钢渣
泡沫混凝土
重金属
安全性
stainless steel slag
foam concrete
heavy metal
safety