High-quality salt separation system and method for fly ash washing liquid

The invention discloses a high-quality salt separation system and method for fly ash washing liquid. The high-quality salt separation system comprises a feeding treatment module, a salt separation module, a sodium salt treatment module and a potassium salt treatment module. The salt separation module comprises a forced circulation crystallizer, a sodium salt discharge port is formed in the bottom of the forced circulation crystallizer, a mother liquor overflow port is formed in the side wall of the forced circulation crystallizer, and the salt separation module is suitable for separating materials into sodium salt slurry and potassium-containing mother liquor; the sodium salt slurry and the potassium-containing mother liquor are respectively conveyed to the sodium salt treatment module and the potassium salt treatment module; the sylvite treatment module comprises a continuous regulator and a continuous crystallizer which are connected in sequence, the continuous regulator is suitable for automatically regula