Method for separating and purifying phosphoric acid and phosphogypsum from wet-process phosphoric acid slurry, and phosphoric acid and phosphogypsum prepared thereby

A method for separating and purifying phosphoric acid and phosphogypsum from a wet-process phosphoric acid slurry, which comprises the following steps:

• (1) adding an impurity-removal agent to the wet-process phosphoric acid slurry, mixing the same under the action of a micro-nano bubble external field to obtain a colloidal impurity-containing organic phase and an impurity-removed mineral slurry;
• (2) subjecting the impurity-removed mineral slurry obtained in step (1) to crystallization and solid-liquid separation in sequence to obtain phosphoric acid and phosphogypsum with impurities removed;
• wherein step (1) comprises:
• mixing a phosphate ore with a returning acid solution, dissolving, adding a reaction acid, and then performing an acidolysis reaction to obtain the wet-process phosphoric acid
• wherein the impurity-removal agent in step (1) is a phosphate ester substance, a ketone substance, a diluent, and an organic additive having phosphorus-hydroxyl;
• wherein in step (1), a volume ratio of the wet-process phosphoric acid slurry to the impurity-removal agent is 1:(0.2-0.9);
• and wherein in step (1), the micro-nano bubble external field is to introduce micro-nano bubbles with a size of between 10 nm to 80 μm into the wet-process phosphoric acid slurry comprising the impurity-removal agent;
• wherein a ratio of a volume flow rate of the micro-nano bubbles to a flow rate of the wet-process phosphoric acid slurry comprising the impurity-removal agent is 1:(15-50).