介绍利用磷石膏与碳铵、氯化钾进行两步复分解反应制取农用硫酸钾的副产物——氯化铵钾母液与碳酸钙对磷酸中和脱氟，制取饲料磷酸氢钙的小试研究情况。第一步用混合脱氟剂中和控制ｐＨ≥２、ｍ （Ｐ２Ｏ５）／ｍ （Ｆ）≥３２０、磷得率≥９０％ ；第二步用碳酸钙中和到ｐＨ＝ ５．８～６．０，即可得到合格的饲料级磷酸氢钙。第一步中和过滤所得脱氟渣可用于制取三元复混肥。 Introduced the use of phosphogypsum and ammonium bicarbonate, potassium chloride for two-step metathesis reaction of agricultural potassium sulfate by-product - ammonium chloride potassium mother liquor and calcium phosphate on the phosphoric acid and defluorination, preparation of feed calcium hydrogen phosphate small test Research situation The first step with mixed defluorination agent neutralization control pH ≥ 2, m (P2O5) / m (F) ≥ 320, phosphorus yield ≥ 90%; the second step with calcium carbonate and to pH = 5.8 ~ 6 .0, you can get qualified feed grade dicalcium phosphate. The first step and filter the resulting de-fluoride residue can be used to prepare ternary compound fertilizer.