硝酸磷肥生产过程中氟化物的回收

Recovery of Fluoride in Production Process of Nitrophosphate

介绍了硝酸磷肥生产过程中采用添加脱氟回收剂的方法从母液中回收氟硅酸钾。采用正交实验验证了酸度、脱氟回收剂、反应时间、加料温度以及添加碳酸铵对氟化物去除的影响。实验结果表明，氟回收的理想条件是：酸不溶物用常温下酸性水逆流洗涤3次，每次用水量为100g湿酸不溶物加水100mL，洗涤后的水返回母液；母液酸度（以硝酸计）为46％-40％，每升母液添加GZ-1脱氟回收剂30—60g，加料反应温度为30-40℃。以回收80％的氟为例，消耗磷矿48万t/a可回收氟硅酸钾2万t／a。

Author has introduced the recovery of potassium fluorosilieate from the mother liquid using the method to add the de-fluor recovery agent in the production process of nitrophosphate. Using the orthogonal experiment, author has proved the influence of the acidity, de-fluor recovery agent, reaction time, feed temperature and adding the ammonium carbonate on the fluoride removal. The ideal conditions of the fluor recovery are： Washing the acidic insoluble in eountercurrent direction three times by acidic water at atmospheric temperature, in every time the water consume is 100 ml added for each 100 g wet acidic insoluble, the water after washing is to be returned to mother liquid; the acidity （as nitric acid） of the mother liquid is 46% - 40%, the adding quantity of fluor recovery agent GZ - 1 is 30 -60 g per liter of mother liquid, the feed reaction temperature is 30 -40 ℃. Taking the fluor recovery rate being 80% as the example, 20 000 t/a of potassium fluorosilieate can be recovered for a consume of phosphor ore 480 000 t/a.