高铝粉煤灰碱石灰低钙烧结熟料的浸出  

Leaching of high alumina fly ash sintered clinker with low lime dosage

作　　者：郑欢 冯晓兰[3] 赵博[3] 杨岗 杨鹏程 刘宇春 张锦飞 ZHENG Huan;FENG Xiaolan;ZHAO Bo;YANG Gang;YANG Pengcheng;LIU Yuchun;ZHANG Jinfei(Shanxi Coal Chemial Industry Technology Research Institute Co.,Ltd.,Xi′an 710055,China;Xi′an Hi-TECH Industries Development Zone Environmental Protection Bureau,Xi′an 710055,China;Xi′an University of Architecture and Technology,Xi′an 710055,China)

机构地区：[1]陕西煤业化工技术研究院有限责任公司,陕西西安710055 [2]西安高新区环境保护局,陕西西安710055 [3]西安建筑科技大学,陕西西安710055

出　　处：《洁净煤技术》2021年第3期275-280,共6页Clean Coal Technology

摘　　要：以高铝粉煤灰碱石灰低钙干法烧结法得到的熟料为原料开展浸出工艺研究,考察了浸出温度、浸出时间、液固比以及碱液浓度等对熟料中铝酸钠浸出率的影响,探索氧化铝熟料中铝酸钠的浸出试验最佳工艺参数,通过XRD、SEM对浸出前后的氧化铝熟料进行物相表征,探讨氧化铝熟料中NaAlO_(2)浸出的动力学。结果表明:在浸出温度65℃、浸出时间7 min、液固比5,碱液浓度0的条件下,铝酸钠的浸出率可以达到94%以上,相较于传统的铝土矿标准浸出中规定的温度(85±1)℃条件下浸出15 min,氧化铝熟料中铝酸钠的浸出时间短、低碱耗、氧化铝浸出率高、浸出工艺简单。利用缩核模型对氧化铝熟料铝酸钠(NaAlO_(2))的浸出过程进行动力学分析,其表观活化能为26.585 kJ/mol,反应符合混合控制,浸出反应活化能较低。为粉煤灰碱石灰悬浮态预热预分解-低钙干法烧结工业实践提供基本参数,新工艺在一定程度上减少碱的消耗,缩短浸出时间,提高铝的浸出效率,推进高铝粉煤灰提取氧化铝工业化进程。In this paper,the leaching technology of high-alumina fly ash from the clinker obtained by low-calcium dry sintering of soda lime was studied.The effects of leaching time,leaching temperature,liquid-solid ratio and alkali concentration on the leaching rate of sodium aluminate in clinker were investigated.The optimum technological parameters for leaching sodium aluminate from alumina clinker were explored.The phase of clinker was characterized by XRD and SEM before and after leaching.The kinetics of NaAlO_(2) in leached alumina clinker was discussed.The results show that the leaching rate of sodium aluminate reaches more than 94%under the conditions of leaching time 7 min,leaching temperature about 65℃,liquid-solid ratio 5,and alkali concentration 0.Compared with the traditional standard leaching of bauxite at the temperature of(85±1)℃for 15 min,the leaching process is simple,the consumption of alkali is low,the leaching time is short and the leaching efficiency of aluminum is high.The kinetic analysis of sodium aluminate(NaAlO_(2))leaching process of alumina clinker was carried out by shrinking core model,and its apparent activation energy was 26.585 kJ/mol.The reaction is under mixed control and the activation energy of leaching reaction is low.This study provides basic parameters for the industrial practice of fly ash preheating and precalciner-lime suspension precalciner-low calcium dry sintering.The new process can reduce the consumption of alkali,shorten the leaching time,improve the leaching efficiency of aluminum,and promote the industrialization process of extracting alumina from high aluminum fly ash.

关 键 词：氧化铝熟料 低钙烧结 浸取 动力学 

分 类 号：TF803.2[冶金工程—有色金属冶金]