脱镁母液制备磷酸铵镁过程中的粒度分布  

Crystal size distribution of struvite in preparation process by mother liquor from magnesium-hydroxide production

作　　者：刘刚[1] 王学魁[1] 段瑛锋[1] 沙作良[1] 袁建军[1] 

机构地区：[1]天津科技大学天津市海洋资源与化学重点实验室,天津300457

出　　处：《无机盐工业》2011年第6期24-26,共3页Inorganic Chemicals Industry

基　　金：天津市科技支撑重点项目(108ZCKFSH02400)

摘　　要：以脱镁母液和磷酸为原料,采用半间歇操作方式制备磷酸铵镁,研究了操作条件(包括搅拌转速、加料位置、加料速度、反应物浓度、晶种加入量)对磷酸铵镁晶体粒度分布的影响。结果表明:适当提高搅拌转速、降低加料速度和降低反应物浓度均可增大产品的平均粒径并减小其变异系数;在桨区加料所得产品平均粒径较大且粒度分布较好;加入适量晶种可以显著增大产品的平均粒径并使其粒度分布更加均匀。Struvite was prepared by semi-batch method with phosphoric acid and the mother liquor from magnesium-hy- droxide production as raw materials. Influences of operating conditions, such as stirring speed, feed location, feed rate, react- ant concentration, and adding amount of seed, on crystal size distribution （ CSD } of struvite were investigated. Results showed properly increasing stirring speed, decreasing feed rate, or decreasing reactant concentration all could make the aver- age crystal size increase and the coefficient of variation（ C. V. ） decrease;feeding in the propeller area could create larger crystal size and better CSD than feeding in the surface; and seeding appropriately could cause average size of products in- crease significantly and the CSD more uniform.

关 键 词：海水利用 磷酸铵镁 反应结晶 粒度分布 

分 类 号：TQ132.2[化学工程—无机化工]