高铝粉煤灰高效增值利用新技术

New Technology of Efficient Value-added Utilization of High Alumina Fly Ash

针对当前高铝粉煤灰综合利用技术难题,提出了高铝粉煤灰预脱硅烧结法提取氧化铝新工艺。新工艺取消了铝酸钠溶液碳酸化分解工序,改为全种子分解工艺。通过合成技术优化,采用高苛性比合成技术,种分母液与预脱硅后的硅酸钠溶液可制备出合格的洗涤用4A沸石。生产过程中,通过补充少量水玻璃用于调节氢氧化铝和4A沸石两种产品的产出比例,可以较好地保障生产系统物料平衡。新工艺取消了石灰炉、氧化铝焙烧炉、铝酸钠溶液碳酸化分解和深度脱硅工序,工艺能耗降低,废渣排放量减少,碳排放量降低。此技术生产流程相对简单、技术可行、经济性好、竞争力较强。

A new process to extract alumina from high alumina fly ash by pre-desilication sintering process was proposed to solve the technical problem of comprehensive utilization of high alumina fly ash.The new process cancelled carbonation decomposition of sodium aluminate solution and applied whole seed decomposition process.By optimizing the synthesis technology and using high caustic ratio synthesis technology,4A zeolite for washing can be produced from spent liquor and sodium silicate solution.In production process,by supplementing a small amount of sodium silicate for adjusting output of aluminum hydroxide and 4A zeolite,material balance of production system can be better guaranteed.The new process eliminated lime furnace,alumina baking furnace,sodium aluminate solution carbonation decomposition and deep desilication process,which reduces energy consumption,waste residue emission and carbon emission.The production process of this technology is relatively simple,technical feasibility,good economy and has strong competitiveness.