Hou Cuihong, Li Luyi, Hou Lishuang, Liu Bingbing, Gu Shouyu, Yao Yuan, Wang Haobin
School of Chemical Engineering, Zhengzhou University, Zhengzhou 450001, China.
Materials (Basel). 2021 Apr 20;14(8):2080. doi: 10.3390/ma14082080.
Yellow phosphorus slag (YPS) is a typical industrial solid waste, while it contains abundant silicon micronutrient required for the growth of rice. The key scientific problem to use the YPS as rice fertilizer is how to activate the slag efficiently during the phosphorite reduction smelting process. In this work, an alkaline rice fertilizer from the activated YPS was successfully prepared to use the micronutrients. Thermodynamic analyses of SiO-CaO, SiO-CaO-AlO and SiO-CaO-AlO-MgO systems were discussed to optimize the acidity for reduction smelting. Results showed that the reduction smelting followed by the water quenching process can realize the reduction of phosphorite and activation of YPS synchronously. Ternary acidity m(SiO)/(m(CaO) + m(MgO)) of 0.92 is suitable for the reduction smelting and activation of the slag. After smelting, the molten YPS can be effectively activated by water quenching, and 78.28% P, 90.03% Ca, and 77.12% Si in the YPS are activated, which can be readily absorbed by the rice roots. Finally, high-strength granular rice fertilizers with a particle size of Φ2-4 mm were successfully prepared from the powdery nitrogen-phosphorus-potassium (NPK) and activated YPS mixture.
黄磷渣（YPS）是一种典型的工业固体废弃物，然而它含有水稻生长所需的丰富硅微营养素。将黄磷渣用作水稻肥料的关键科学问题是如何在磷矿还原熔炼过程中有效活化该渣。在本研究中，成功制备了一种由活化黄磷渣制成的碱性水稻肥料以利用这些微营养素。对SiO-CaO、SiO-CaO-AlO和SiO-CaO-AlO-MgO体系进行了热力学分析，以优化还原熔炼的酸度。结果表明，还原熔炼后进行水淬处理可同步实现磷矿的还原和黄磷渣的活化。三元酸度m(SiO)/(m(CaO) + m(MgO))为0.92适合该渣的还原熔炼和活化。熔炼后，熔融的黄磷渣通过水淬可得到有效活化，黄磷渣中78.28%的P、90.03%的Ca和77.12%的Si被活化，这些元素可被水稻根系轻易吸收。最后，由粉状氮磷钾（NPK）和活化黄磷渣混合物成功制备出粒径为Φ2 - 4 mm的高强度颗粒状水稻肥料。
