Valorization of a bottom ash and a waste from mining industry for the production of geopolymers

来源 :The 14th International Congress on the Chemistry of Cement ( | 被引量 : 0次 | 上传用户:Fishfag
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  Geopolymers are a new type of cement, obtained through a chemical reaction between an amorphous aluminosilicate precursor and an alkaline activator, resulting in the formation of hardened material.Nowadays,there is particular interest in the development of these novel cements due to its lower environmental footprint when compared to ordinary Portland cement (OPC), as well as their technical advantages, including high compressive strength, low permeability and higher chemical stability under certain conditions of exposure.This paper assesses the use of two industrial wastes generated in a large volume in Brazil, which are currently disposed in landfills, and have no commercial value.A kaolinitic sludge from the mining industry (CKS) and a bottom ash (BA) generated during coal combustion in a thermal station were used as precursors.Thermal and mechanical treatments were applied to the raw materials in order to increase their reactivity.The CKS/BA blends geopolymers were synthesized with an overall SiO2/Al2O3 molar ratio between 4 and 5, an overall Na2O/SiO2 molar ratio of 0.25.The reaction products formed during the geopolymerisation were assessed up to 90 days of curing by different characterization techniques, including isothermal calorimetry, X-ray diffractometry, Fourier transformed infrared spectroscopy, and thermogravimetric analysis.Complementary,compressive strength at different ages of curing were also determined.The results show these waste are suitable precursor for the production of alternative geopolymers-based cement, with compressive strength higher than 45 MPa after 7 days of curing The content of silicates soluble in the alkali activator (through the adjustment of the SiO2/Al2O3 molar ratio) plays an important role during the geopolymerization.Increase the silicates content lead the formation of a highly dense and crosslinked Si-enriched type gel with low Al content when compared to the geopolymers produced with lower SiO2/Al2O3 molar ratio.This elucidates that geopolymerisatios can be a viable solution for the valorization of these industrial wastes.
其他文献
  A novel clinker with low Ca/Si ratio (low CO2 emissions) and low sintering temperature (low energy consumption) was synthesized.The clinker mainly contains
会议
受国家科技部资源与配置司委托,国家科技部科技评估中心于8月13日,在广东省珠海市,对由中国地震局组织的、珠海泰德企业有限公司牵头实施的国家重大科学仪器设备开发专项中的
  This paper describes a study of the hydration of belite-yeelimite ferrite (BYF) cements, made from clinkers comprising principally belite (C2S), with yeelim
会议
1.西晋作家左思,小时候学书学琴,都学不好,谈话还有点口吃。他父亲认为他不够聪明,有一次竟当朋友的面说:“这孩子比起我小时候来,差得远呢!” 1. Zuo Si, a writer in the
随着我国总体经济的不断发展,已经实现了推进我国的全面城市化建设,因此为了确保城乡居民在生活发展的过程中能够享有政府所提供的一切基本权益,则需要保证在各个公益事业单
浦东机场外侧滩涂促淤圈围工程北起白龙港顺堤,南至浦东机场薛家泓泵闸,东至-1m~-2m线滩地,工程采取先促淤、后圈围成陆的总体实施方式。促淤面积约2.3万亩,堤线长13.9km。针
  CSA (calcium sulfoaluminate) cement has been developed mainly from three types of compounds: calcium oxide, aluminum oxide and sulfur oxide.Some typical raw
会议
我国财政部于2016年发布了《关于开展行政事业单位内部控制基础性评价工作的通知》,该通知中明确表示,我国行政事业单位需要不断优化自身发展结构,对内控建设工作的开展进行
在当前社会经济不断发展以及科学技术水平快速提高的背景下,建筑经济具有极好的发展前景.基于此,本文通过对建筑经济进行调查和掌握,重点分析在宏观经济的条件下,装配式和房
针对Φ1.3m口径同轴四反望远镜镜头,提出了一种有效的装调方法.主镜口径为1.3m,采用背部双脚架(bipod)支撑形式.使用激光跟踪仪多边测量法对支撑结构精密定位,利用Stewart机