摘要
固硫灰渣是循环流化床燃煤技术的主要副产物,如何高效、清洁地利用这一类固体废弃物是一个亟待解决的问题。本文根据近年来国内外对固硫灰渣的研究成果,从化学组成、矿物组成、微观结构、典型特性等方面综述了固硫灰渣的主要特征。相较于粉煤灰等其他燃煤副产物,固硫灰渣中存在游离氧化钙、硫酸钙和无定形铝硅酸盐物质,且颗粒疏松多孔,这导致其具有明显的火山灰活性、自硬性和水化膨胀性等特性。同时本文分析了固硫灰渣作为水泥混合材使用时需要注意的几个关键问题。结果表明,固硫灰渣特殊的组成、微结构和性质导致其作为水泥混合材使用时,必须考虑使用合适的激发剂提高灰渣活性,调整养护工艺、用水量等条件提高制品的安定性,并以添加减水剂等方式控制水泥制浆中的需水量,提高水泥石强度。这为有效实现固硫灰渣的建材资源化利用提供一定指导。
Fluidized bed combustion(FBC)ash is an effective technology for burning the fuels containing sulphur with low SO 2 emissions.It is an important issue that how to utilize the FBC ashes in an efficient and clean way.In this paper,the major characteristics of FBC ashes in terms of chemical and mineral compositions,microstructures,properties were reviewed.Compared with fly ashes and other by-products from coal burning,FBC ashes with porous structure contain free CaO,CaSO 4 and amorphous aluminosilicate,which leads to the obvious pozzolanic activity,self-hardening and hydration expansion.At the same time,several key issues in the application of FBC ashes as cement admixtures base on their composition,microstructure and properties were discussed.The results show that suitable activators should be used to enhance the activity of ashes.The stability needs to be improved by adjusting the curing process,water-cement ratio and other conditions.Adding water reducing agents controls the water requirement and increases cement strength.This provides some guidances for effective utilization of the building materials with FBC ashes.
作者
刘虎林
王昭
伍媛婷
任思谦
王巍
韩桂英
LIU Hulin;WANG Zhao;WU Yuanting;REN Siqian;WANG Wei;HAN Guiying(Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials,School of Materials Science and Engineering,Shaanxi University of Science&Technology,Xi’an 710021,China;Shaanxi Zhengyuan Environmental Protection Technology Industry(Group)Co.,Ltd.,Xi’an 712085,China)
出处
《硅酸盐通报》
CAS
北大核心
2021年第6期2052-2061,2069,共11页
Bulletin of the Chinese Ceramic Society
关键词
固硫灰渣
组成
微结构
水化活性
水泥混合材
fluidized bed combustion ash
composition
microstructure
hydration activity
cement admixture
