摘要
对潞安煤经循环流化床、煤粉炉和气化炉处理后得到的煤灰进行了化学组成、矿物组成、特征基团、粒径分布、比表面积及微观形貌等理化性质的对比研究,并考察了其在酸浸和碱浸过程中Al^3+,Si^4+,Fe^3+,Ca^2+,K^+和Ti^4+等离子的溶解特性。结果表明:不同炉型潞安煤灰中铝、钙、硫等元素的含量有明显的差异;矿物组成包括晶相的鳞石英、方石英、莫来石、硬石膏及非晶相的偏高岭石、假莫来石、无定型二氧化硅等;相比较而言,气化炉灰中铝硅酸盐矿物结构更加不稳定。循环流化床灰颗粒呈具有一定孔洞结构的不规则状,而煤粉炉灰和气化炉灰均为光滑球形颗粒,循环流化床灰的粒径>煤粉炉灰的粒径>气化炉灰的粒径,循环流化床灰的比表面积>气化炉灰的比表面积>煤粉炉灰的比表面积。在HCl溶液中,Al^3+,Fe^3+,Ca^2+,K^+,Ti^4+的溶出率均较高;在NaOH溶液中,仅Si^4+和K^+的溶出率较高。不同炉型潞安煤灰中各元素的溶出率具有较大差异,主要与其矿物组成、结构稳定性、粒径和比表面积等相关。
The physicochemical properties, such as chemical component, mineral composition, characteristic group, particle size distribution, specific surface area and micromorphology of Lu’an coal ash gathered from the circulating fluidized bed, pulverized-coal furnace and gasifier were compared. The dissolution characteristics of Al^3+, Si^4+, Fe^3+, Ca^2+, K^+ and Ti^4+ ions of Lu’an coal ash during the acid leaching and the alkali leaching processes were also investigated. The results show that are significant differences in the chemical components of aluminum, calcium and sulfur for the different kinds of Lu’an coal ash. They mainly consiste of crystalline minerals(tridymite, cristobalite, mullite and anhydrite) and non-crystalline minerals(metakaolin, pseudo-mullite and amorphous silica). In addition, the structure stability of the aluminosilicate mineral in the gasification ash is more unstable than that in the circulating fluidized bed ash and pulverized-coal fly ash. Circulating fluidized bed ash particles appear in the irregular shapes while the pulverized-coal fly ash and gasification ash are smooth spherical particles. The order of the particle size from large to small is circulating fluidized bed ash, pulverized-coal fly ash, gasification ash;and the order of the specific surface area from large to small is circulating fluidized bed ash, gasification ash, pulverized-coal fly ash. The dissolution of Al^3+, Fe^3+, Ca^2+, K^+ and Ti^4+ in HCl solution is high;while the dissolution of Si^4+ and K+ in NaOH solution is high. The dissolution of various elements from the different kinds of Lu’an coal ash is remarkably different, mainly related to their mineral composition, structural stability, particle size and specific surface area.
作者
张学里
燕可洲
马志斌
郭彦霞
程芳琴
ZHANG Xueli;YAN Kezhou;MA Zhibin;GUO Yanxia;CHENG Fangqin(State Environmental Protection Key Laboratory on Efficient Resource-utilization Techniques of Coal Waste,Collaborative Innovation Center of High Value-added Utilization of Coal-related Waste,Institute of Resources and Environmental Engineering,Shanxi University,030006 Taiyuan,China)
出处
《煤炭转化》
CAS
CSCD
北大核心
2020年第1期81-88,共8页
Coal Conversion
基金
国家重点研发计划项目(2017YFB0603101)
山西省面上青年基金资助项目(201801D221325)
襄垣县科技攻关项目(2018XYSDJS-02)
关键词
循环流化床灰
煤粉炉灰
气化炉灰
理化性质
离子溶出
circulating fluidized bed ash
pulverized-coal fly ash
gasification ash
physical and chemical characteristic
ion dissolution
