摘要
粉煤灰是从煤燃烧后的烟气中收捕的细灰,是燃煤电厂排出的主要固体废物,危害环境和人类健康。利用粉煤灰制备陶粒是粉煤灰资源化的重要途径之一。粉煤灰陶粒因密度小、质轻、保温、隔热、耐火性好、抗震性能好、吸水率低、抗冻性能和耐久性能好等优异性能,在废水处理、废气处理、噪声控制和建筑材料等领域具有广阔的应用前景。综述了近年来粉煤灰陶粒的最新发展动态,分别对焙烧法和免烧法制备粉煤灰陶粒进行了可行性分析,介绍了粉煤灰陶粒的相关研究成果,着重介绍了生产粉煤灰焙烧陶粒和粉煤灰免烧陶粒的机理、所用原料、工艺条件及产品性能。同时提出了我国在粉煤灰综合利用过程中面临的主要问题及解决措施,并对今后的发展趋势进行展望,为粉煤灰制备陶粒的机理研究和工艺研究提供参考。粉煤灰焙烧陶粒的制备过程主要包括配料、混合、造粒、干燥、预烧、焙烧、冷却和筛分等过程;影响其性能的主要因素有原料配比、预热时间、预热温度、升温速率、煅烧时间、煅烧温度等。粉煤灰免烧陶粒的制备过程主要包括配料、混合、造粒、陈化、干燥、养护和冷却等过程;影响其性能的主要因素有原料性质、激发剂掺量、黏结剂用量、发泡剂种类及用量、养护方式、蒸养温度和养护时间等,可通过改变工艺条件,制备出不同性能和用途的产品。目前,我国的粉煤灰陶粒以焙烧型为主。焙烧陶粒具有技术成熟、产品强度高等优势,但存在能耗高、投资大、工艺复杂等缺点。因此,开发粉煤灰免烧陶粒就成为发展的新趋向。我国的免烧陶粒尚处于研制阶段,虽然产品强度低、比表面积小,但克服了焙烧法制备陶粒成本高、污染大等缺点,可将其应用于对筒压强度要求偏低、堆积密度要求偏高的场合。为提高陶粒的性能、降低成�
Fly ash is the fine ash collected from the flue gas after coal combustion,which is the main solid waste discharged from coal-fired power plants,and has great harm to the environment and human health.The preparation of ceramsite by using fly ash is one of the important ways to recycle fly ash.Because of its excellent properties such as small density,light weight,heat preservation,heat insulation,good fire resistance,good anti-seismic performance,low water absorption,good anti-freezing performance and good durability,the fly ash ceramsite has wide application prospects in the fields of waste water treatment,waste gas treatment,noise control and building materials,etc.In this review,the latest development of fly ash ceramisite in recent years was reviewed and the feasibility of preparing fly ash ceramsite by roasting process and unburned process was analyzed.The related research results of fly ash ceramisite were introduced.The mechanism,raw materials,technological conditions and product properties of producing roasting ceramsite and unburned ceramsite by using fly ash were emphatically introduced.At the same time,the main problems and solutions in the comprehensive utilization of fly ash in China were put forward and the future development trend was forecasted,so as to provide reference for the research on the mechanism and technology of preparing ceramsite with fly ash.The results show that the preparation process of fly ash roasted ceramsite mainly includes batching,mixing,granulation,drying,pre-firing,roasting,cooling and screening.The main factors that affect the properties of the roasted ceramsite are raw material ratio,preheating time,preheating temperature,heating rate,calcination time,calcination temperature,etc.The preparation process of fly ash unburned ceramsite mainly includes batching,mixing,granulation,aging,drying,curing and cooling.The main factors that affect the properties of the unburned ceramsite are the properties of raw materials,the amount of activator,the amount of binder,the type and amount
作者
柴春镜
宋慧平
冯政君
张金才
程芳琴
CHAI Chunjing;SONG Huiping;FENG Zhengjun;ZHANG Jincai;CHENG Fangqin(State Environmental Protection Key Laboratory of Efficient Resource Utilization Techniques of Coal Waste,Institute of Resources and Environmental Engineering,Shanxi University,Taiyuan 030006,China)
出处
《洁净煤技术》
CAS
2020年第6期11-22,共12页
Clean Coal Technology
基金
山西省揭榜招标项目(20191101007)
山西省重点研发计划资助项目(201903D421002)
襄垣县固废综合利用科技攻关项目(2018XYSDYY-11)。
关键词
粉煤灰
焙烧陶粒
免烧陶粒
fly ash
roasted ceramsite
unburned ceramsite