煤气化细灰熔渣制备泡沫微晶玻璃  

Preparation of porous glass-ceramics from coal gasification fine ash slag

作　　者：周丽 任强强[1,2] 崔瑞芳 李林宣 李伟 ZHOU Li;REN Qiangqiang;CUI Ruifang;LI Linxuan;LI Wei(State Key Laboratory of Coal Conversion,Institute of Engineering Thermalphysics,Chinese Academy of Sciences,Beijing100190,China;University of Chinese Academy of Sciences,Beijing100049,China)

机构地区：[1]中国科学院工程热物理研究所煤炭高效低碳利用全国重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《洁净煤技术》2024年第7期69-77,共9页Clean Coal Technology

基　　金：中国科学院A类战略性先导科技专项资助项目(XDA29020300);中国科学院稳定支撑基础研究青年团队计划资助项目(YSBR-028)。

摘　　要：由于缺乏成熟的大规模工业化处置技术,大量堆存的煤气化细灰造成严重的环境污染和资源浪费。流化熔融处置煤气化细灰可实现碳灰分离和灰分的改性提质,使灰分转变为富硅铝元素的玻璃相熔渣;泡沫微晶玻璃由于其特殊的玻晶交织结构使其具有良好的机械性能和保温隔热性能,确立了熔渣制备泡沫微晶玻璃的高值化利用思路。以煤气化细灰熔渣为原料,采用无机凝胶铸造工艺制备泡沫微晶玻璃,研究了主要工艺参数预固化时间和烧结温度对泡沫微晶玻璃析晶特性、孔结构和抗压强度的影响。结果表明:泡沫微晶玻璃析晶特性和孔结构与烧结温度、预固化时间均呈现相关性。较高的烧结温度可促进烧结过程中晶相析出进而强化泡沫微晶玻璃的抗压强度。预固化时间影响泡沫玻璃胚体的网络结构,导致晶相析出时克服的阻力不同,从而影响晶相种类。预固化时间30 min时,泡沫玻璃胚体在烧结析晶过程中易发生大孔径孔隙坍塌。抗压强度随孔隙率的增大而减小,随孔径增加呈非线性减小。预固化时间为90 min时,可获得良好的孔隙结构。抗压强度受到析晶特性和孔隙结构特性的共同作用。烧结温度900℃时可强化抗压强度,尤其是预固化时间90 min时,泡沫微晶玻璃的抗压强度为3.77 MPa;而700和800℃时,抗压强度是否增大与预固化时间相关。预固化时间60 min、烧结温度900℃时,析出大量晶体,孔隙率为66.20%且孔径均匀分布,抗压强度为1.40 MPa。Due to the lack of mature large-scale industrial disposal technology,a large amount of coal gasification fine ash has caused seri-ous environmental pollution and resource waste.The treatment of coal gasification fine ash by fluidization melting can realize the separation of carbon and ash,and the modification and improvement of ash,so that ash can be transformed into glass phase slag rich in silicon and aluminum elements.Because of its special glassy interwoven structure,porous glass-ceramics have good mechanical properties and thermal insulation properties,so the idea of high value utilization of molten slag to prepare porous glass-ceramics was established.The effects of pre-curing time and sintering temperature on crystallization characteristics,pore structure and compressive strength of porous glass-ce-ramics were studied.The results show that the crystallization characteristics and pore structure of porous glass-ceramics are related to sin-tering temperature and pre-curing time.The higher sintering temperature can promote the crystal phase precipitation in the sintering process and strengthen the compressive strength of the porous glass-ceramics.The pre-curing time affects the network structure of the por-ous-glass embryo,resulting in different resistance to be overcome during crystal precipitation,which affects the type of crystal phase.When the pre-curing time is 30 min,the large pore size of the porous-glass embryo is easy to collapse during the process of sintering and crystallization.The compressive strength decreases with the increase of porosity and decreases nonlinearly with the increase of pore size.When the pre-curing time is 90 min,a good pore structure can be obtained.The compressive strength is influenced by the crystalli-zation characteristics and the pore structure characteristics.When the sintering temperature is 900℃,the compressive strength can be strengthened,especially when the pre-curing time is 90 min,the compressive strength of the porous glass-ceramics is 3.77 MPa.At 700℃and 800℃

关 键 词：熔渣 泡沫微晶玻璃 预固化时间 烧结温度 孔隙结构 抗压强度 

分 类 号：TB321[一般工业技术—材料科学与工程]