| 摘要 |
<p>Sodium ammonium phosphate and ammonium chloride are prepared from an ammonium phosphate (e.g., diammonium phosphate) and sodium chloride in water. The crystallization of sodium ammonium phosphate may take place between -10 °C to 40 °C. Using the present invention, technical grade sodium ammonium phosphate and ammonium chloride can be produced from fertilizer grade diammonium phosphate. Water (2) and diammonium phosphate (1) are metered in suitable proportions into a dissolver (3). The slurry (4) is then sent to a vacuum filter or clarifiers (5) to get rid of insoluble materials. The clear diammonium phosphate solution (7) is then sent to a reactor (8) where technical grade sodium chloride, or salt, is metered in and reacted. The resulting slurry (10) may then be sent to a cooling crystallizer (11) and cooled to a low temperature. For example, -5 °C, and the cooled slurry (12) may be centrifuged in centrifuge (13). The sodium ammonium phosphate crystals (15) from centrifuge (13) may be dried at dryer (16).</p> |
