【摘要】 为了利用柴达木地区自然蒸发条件,提出介稳状态下氯化镁与硫酸铵为原料生产硫酸镁铵复肥的设想,采用等温蒸发法测定了25℃时Mg²⁺,NH₄⁺//Cl^-,SO₄^2--H₂O体系及其三元子体系的介稳相平衡数据,并绘制了介稳相图。结果表明:（NH₄）₂SO₄-MgSO₄-H₂O体系有2个共饱点,5个结晶区;MgCl₂-MgSO₄-H₂O体系有3个共饱点,7个结晶区;Mg²⁺,NH₄⁺//Cl^-,SO₄^2--H₂O四元体系存在6个共饱点和8个结晶区,分别为:MgSO₄·（NH₄）₂SO₄·6H₂O结晶区,（NH₄）₂SO₄结晶区,NH₄Cl结晶区,MgCl₂·NH₄Cl·6H₂O结晶区,MgSO₄·7H₂O结晶区,MgSO₄·6H₂O结晶区,MgSO₄·5H₂O和MgCl₂·6H₂O结晶区。Pitzer模型对实验数据进行了回归计算,计算值与实验值相吻合。确定了通过蒸发结晶生产硫酸镁铵复肥的工艺路线。更多还原

【Abstract】 In order to utilize the natural evaporation conditions in Qaidam area, a process using magnesium chloride and ammonium sulfate as raw materials to produce magnesium ammonium sulfate compound fertilizer was proposed. The metastable solubility of the Mg²⁺, NH₄⁺//Cl^-, SO₄^2--H₂O system and its ternary systems at 25 ℃ were measured using the isothermal evaporation method, and the metastable phase diagrams were plotted. The metastable phase diagram of the ternary system（NH₄）₂SO₄-MgSO₄-H₂O has two invariant points and five crystalline zones. The metastable phase diagram of the ternary system MgCl₂-MgSO₄-H₂O has three invariant points and seven crystalline zones. In the metastable phase diagram of the quaternary system, there are six invariant points and eight crystalline zones that correspond to MgSO₄·（NH₄）₂SO₄·6H₂O,（NH₄）₂SO₄, NH₄Cl, MgCl₂·NH₄Cl·6H₂O, MgSO₄·7H₂O, MgSO₄·6H₂O, MgSO₄·5 H₂O and MgCl₂·6H₂O. Based on the Pitzer model, correlation calculation results show that the calculated value is consistent with the experimental data. A technological process for the production of magnesium ammonium sulfate compound fertilizer by evaporation and crystallization is thus proposed.更多还原