摘要
为解决实际生产中煤矸石浸出氧化铝耗酸量大和浸出时间长等问题,以贵州某地煤矸石为研究对象,以硫酸溶液为浸出介质,浸出率为指标,将以往的常压酸浸工艺改为加压酸浸工艺。研究在浸出过程中反应时间、反应温度、酸矸比和液固比对氧化铝浸出率的影响,获得了加压酸浸过程氧化铝的浸出动力学。结果表明:在反应时间为130 min、反应温度为150℃、酸矸比为1.3∶1、液固比为4∶1时,氧化铝浸出率达到99.32%,酸渣中SiO 2和TiO 2合计质量分数大于98%;120℃~160℃时,浸出过程符合固体产物层(残留层)内扩散控制的“未反应核减缩型”模型,反应活化能为30.62 kJ/mol。相比常压酸浸工艺,加压酸浸工艺不仅实现了煤矸石中Al 2O 3的高效浸出和酸渣中硅钛资源的高效富集,而且减少了反应时间、降低了反应温度和耗酸量,为煤矸石提取氧化铝资源综合利用开辟了新线路。
In order to solve the problems of large acid consumption and long time consumption when leaching alumina from coal gangue in actual production,the previous atmospheric acid leaching process was changed to pressurized process,Guizhou coal gangue as research object,sulfuric acid solution as leaching medium,and the leaching rate as the index.The effects of reaction time,reaction temperature,mass ratio of acid to solid,mass ratio of liquid to solid on the leaching rate of alumina were investigated,as well as the leaching dynamic of alumina during the pressurized process was obtained.The results show that the leachig rate of alumina reaches 99.32%at 150℃for 130 min,mass ratio of acid to solid 1.3∶1,and the mass ratio of liquid to solid 4∶1.The total mass fraction of SiO 2 and TiO 2 in the acid slag is>98%.At the temperature of 120℃~160℃,the leaching process is controlled by the diffusion of the solid product layer(residual layer),which activation energy is 30.62 kJ/mol.Compard with the atmospheric pressure leaching process,the pressurized process not only achieves leaching alumina from coal gangue,enriches silicon and titanium in acid slag efficiently,but also reduces the reaction time,the reaction temperature and the acid consumption of leaching process.
作者
李浩林
夏举佩
曾德恢
郑光亚
辜芳
刘成龙
LI Haolin;XIA Jupei;ZENG Dehui;ZHENG Guangya;GU Fang;LIU Chenglong(Faculty of Chemical Engineering,Kunming University of Science and Technology,650500 Kunming,China;College of Chemistry and Chemical Engineering,Ningxia Normal University,756000 Guyuan,China)
出处
《煤炭转化》
CAS
CSCD
北大核心
2020年第2期89-96,共8页
Coal Conversion
基金
宁夏回族自治区重点研发计划项目(2018BEE03021)
关键词
煤矸石
氧化铝
加压酸浸法
动力学
活化能
coal gangue
alumina
pressurized acid leaching process
dynamics
activation energy
