拜耳法低铁赤泥制备硅钾肥工艺及硅钾活化机理研究  

Preparation of silicon-potassium fertilizer from low-iron red mud of Bayer process and silicon-potassium activation mechanism

作　　者：罗扬 田江南 丁健 郑诗礼[4] 吴应红[5] Luo Yang;Tian Jiangnan;Ding Jian;Zheng Shili;Wu Yinghong(Department of Civil Engineering, The University of Hong Kong, Hong Kong 999077, China;Hong Kong Productivity Council(HKPC),Hong Kong 999077,China;North China Power Engineering CO., Ltd. of China Power Engineering Consulting Group, Beijing 100120, China;Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, China)

机构地区：[1]香港大学土木工程系,香港999077 [2]香港生产力促进局,香港999077 [3]中国电力工程顾问集团华北电力设计院有限公司,北京100120 [4]中国科学院过程工程研究所,北京100190 [5]香港大学机械工程系,香港999077

出　　处：《武汉科技大学学报》2021年第1期27-33,共7页Journal of Wuhan University of Science and Technology

基　　金：香港研究资助局资助项目(T21-711/16-R;City U 11205617);香港城市大学策略研究基金资助项目(7005505).

摘　　要：本研究采用KOH水热处理工艺实现了拜耳法低铁赤泥中有毒钠元素的深度脱除,且同时活化了其中硅、钾等有益元素,将赤泥固废清洁转化为无机硅钾肥产品。分析表明,在KOH水热过程中,主要是含钠物相方钠石分解转化为钾沸石,同时钠元素进入液相,而钙铝榴石不参与反应。钾沸石相的生成是有效钾含量提升的主要原因,同时水热处理过程中有部分石英相被活化,该相由稳定的不可溶解形态转化为可吸收形态是有效硅含量提升的主要原因。In this study,the KOH hydrothermal method was adopted to remove toxic sodium elements and activate beneficial elements such as silicon and potassium in low-iron Bayer red mud simultaneously,efficiently converting the red mud solid waste into an inorganic silicon-potassium fertilizer.The analysis shows that in the KOH-based hydrothermal process,the sodium-containing sodalite is decomposed and transformed into potassium zeolite,the sodium ions enter into the liquid phase,while the katoite does not participate in the reaction.The formation of potassium zeolite is the main reason for the increase of available potassium content.Meanwhile,some quartz is activated and converted from a stable insoluble form to an absorbable form,causing the increase of available silicon content.

关 键 词：拜耳法赤泥 KOH 水热法 脱钠 硅钾肥 KAlSiO4 活化机理 

分 类 号：X75[环境科学与工程—环境工程]