Multi-element comprehensive utilization process for phosphorus-potassium associated ore

Abstract

The present invention discloses a multi-element comprehensive utilization process for phosphorus-potassium associated ore. The process comprises: firstly, a fluorine-containing compound is used as an additional aid, and a leaching reaction of the phosphorus-potassium associated ore at a low temperature under an acidic condition is implemented, so as to obtain a silica residue and a leachate. The steps of calcium removal, hydrochloric acid distillation and neutralization are then performed successively to the resulting leachate, so as to obtain a calcium sulfate residue, a heavy iron residue, a heavy aluminum residue, a heavy magnesium residue, and a filtrate. The resulting filtrate is then supplemented with phosphorus, evaporated, and concentrated, so as to obtain a high concentration of NPK compound fertilizer. According to the process provided by the present invention, the fluorine-containing compound is used as the additional aid and hydrochloric acid is used as a leaching agent to process the phosphorus-potassium associated ore. Potassium feldspar is decomposed by means of a reaction of villiaumite and an acid to generate hydrofluoric acid in situ, effectively implementing a process of complete decomposition, complete separation and complete utilization. The process has advantages of low energy consumption, a high element leaching rate, and simple subsequent treatment processes, etc. No discharge problem of three waste exists in the treatment process. In addition, the involved process is simple and the reaction conditions are mild, so that the process is easy to implement and is suitable for popularization and application.

Description

technical field

[0001] The invention relates to the field of phosphorus inorganic chemical industry, in particular to a multi-element comprehensive utilization process of phosphorus and potassium associated ore. Background technique

[0002] Phosphorus and potassium fertilizers, as the nutrient element fertilizers of crops, play an extremely important role in the life metabolism process of crops. However, in my country, the output and amount of phosphate fertilizer, potash fertilizer and their compound fertilizers are insufficient, and the ratio of nitrogen, phosphorus and potassium in the application of chemical fertilizers is seriously out of balance. The proportion of compound fertilizer with high phosphorus and potassium is too low.

[0003] The extraction of potassium mainly comes from soluble potassium salt deposits, but it is seriously lacking in our country. According to statistics, in 2012 the world's water-soluble potassium salt reserves were equivalent to K 2 O ...

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