基于XRD及FTIR的固废型纳米高硫水泥的微观特性  

Microstructure Characteristics of Nano Solid Waste High Sulfur Cement Based on XRD and FTIR

作　　者：宗志芳[1,2,3] 龙红明 Yilin Gui[3] 张浩 董伟[2] 周晓慧[2] 季益龙[1] ZONG Zhi-fang;LONG Hong-ming;Yilin Gui;ZHANG Hao;DONG Wei;ZHOU Xiao-hui;JI Yi-long(Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling(Anhui University of Technology),Ma’anshan 243002,China;School of Architecture and Civil Engineering,Anhui University of Technology,Ma’anshan 243032,China;School of Civil and Environmental Engineering,Queensland University of Technology,Brisbane,QLD 4000,Australia)

机构地区：[1]冶金工程与资源综合利用安徽省重点实验室(安徽工业大学),安徽马鞍山243002 [2]安徽工业大学建筑工程学院,安徽马鞍山243032 [3]School of Civil and Environmental Engineering,Queensland University of Technology,Brisbane,QLD 4000,Australia

出　　处：《光谱学与光谱分析》2023年第6期1974-1980,共7页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(52174290);安徽省自然科学基金项目(2108085QE243);冶金工程与资源综合利用安徽省重点实验室(安徽工业大学)开放基金项目(SKF20-06);安徽省省级大学生科研训练计划项目(S202110360221)资助。

摘　　要：水泥中的硫酸盐含量过高会带来后期体积膨胀的风险。采用纳米TiO_(2)和纳米SiO_(2)对含有CaSO_(3)·0.5H_(2)O的半干法烧结烟气脱硫灰改性,以纳米改性半干法烧结烟气脱硫灰为混合材制备固废型纳米高硫水泥,解决混合材中CaSO_(3)·0.5H_(2)O含量高带来的耐久性不良问题。根据固废型纳米高硫水泥的安定性、标准稠度用水量,凝结时间以及抗压强度等性能的发展变化规律,确定了各组分的掺量配比和制备参数。采用LPSA分析了原材料的粒径分布区间,采用接触角测量仪分析了硬化浆体的浸润性能,采用XRD分析了原料及硬化浆体的矿物成分,采用FTIR分析了原料及硬化浆体的组织结构的变化规律,采用SEM分析了原料及硬化浆体的微观形貌。结果表明,半干法烧结烟气脱硫灰的粒径分布区间为0.31~127.38μm比水泥颗粒粒径分布区间更宽、粒度更细,能够优化水泥的级配范围。半干法烧结烟气脱硫灰的加入对水泥水化起到一定的缓凝作用,延长了凝结时间,掺量较大会带来同龄期硬化浆体抗压强度的降低。纳米SiO_(2)与纳米TiO_(2)的加入能够降低高硫水泥体系的标准稠度用水量,提高其抗压强度。3 Wt%的纳米TiO_(2)与2 Wt%的纳米SiO_(2)协同改性能够有效稳定半干法烧结烟气脱硫灰中的CaSO_(3)·0.5H_(2)O,进一步激发半干法烧结烟气脱硫灰的潜在活性,提高水泥硬化浆体的力学性能。改性后固废型纳米高硫水泥28 d的抗压强度为64.72 MPa比未改性的高硫水泥提高了83%,比纯水泥提高了16%。纳米改性后,润湿边角增大向疏水转变,有利于耐久性的提高;XRD分析结果显示水化产物中类AFm’含量很低,降低了膨胀的风险;FTIR分析结果显示水化产物中Ca(OH)_(2)中含有的—OH的伸缩振动峰增强,进一步提高了硬化浆体的抗化学侵蚀能力;SEM分析结果显示水化产物质地均匀,组织缺陷少。纳米TiO_(2)与纳米SiO_(2)�High sulfate content in cement carries risks of volume expansion in late hydration.Nano-TiO_(2)and nano-SiO_(2)were used to modify semi-dry flue gas desulfurization ash,which contains a high rate of CaSO_(3)·0.5H 2O,and nano-modified semi-dry flue gas desulfurization ash was used to prepare nano-solid waste high sulfur cement,to solve the problem of poor durability caused by high CaSO_(3)·0.5H_(2)O content in the matrix.The ratio of each component in nano-solid waste high sulfur cement was determined according to the stability,water requirement of normal consistency,setting time and compressive strength of nano-solid waste high sulfur cement.LPSA was used to analyze the particle size distribution of raw materials.The water contact angle measurement was used to analyze the wettability of hardened slurry,the XRD was used to analyze the mineral composition of raw material and hardened slurry,the FTIR was used to analyze the change of microstructure of raw material and hardened slurry,the SEM was used to analyze the micromorphology of raw material and hardened slurry.The results show that the particle size distribution range of semi-dry flue gas desulfurization ash is 0.31~127.38μm,which is wider and finer than that of cement particles,and so can optimize the grading range of cement.The semi-dry flue gas desulfurization ash could delay the setting of cement hydration,prolong the setting time,and reduce the compressive strength,especially with a large amount.Adding nano SiO_(2)and nano TiO_(2)can reduce the water requirement of normal consistency of cement matrix and improve its compressive strength.The synergistic modification of 3%nano TiO_(2)and 2%nano SiO_(2)can effectively stabilize CaSO_(3)·0.5H 2O in semi-dry flue gas desulfurization ash,further stimulating the potential activity of semi-dry flue gas desulfurization ash and improve the mechanical properties of cement hardened slurry.The 28-day compressive strength of modified nano-solid waste high sulfur cement is 64.72 MPa,83%higher than that of unmodified

关 键 词：半干法脱硫灰 胶凝材料 纳米改性 亚硫酸盐 微观结构 

分 类 号：TU522.1[建筑科学—建筑技术科学]