Non-phosphorus corrosion and scale inhibitor for industrial cooling water system as well as preparation method and application thereof

The invention discloses a non-phosphorus corrosion and scale inhibitor for an industrial cooling water system as well as a preparation method and application thereof. The non-phosphorus corrosion and scale inhibitor is composed of an itaconic acid-diethylene glycol ether-acrylic acid terpolymer, Polyepoxysuccinic Acid (PESA), zinc citrate, Benzotriazole (BTA) and water, wherein the weight percentage of the itaconic acid-diethylene glycol ether-acrylic acid terpolyme in the non-phosphorus corrosion and scale inhibitor is 15.0%-40.0%, the weight percentage of the PESA in the non-phosphorus corrosion and scale inhibitor is 5.0%-20.0%, the weight percentage of the zinc citrate in the non-phosphorus corrosion and scale inhibitor is 5.0%-12.0%, and the weight percentage of the BTA in the non-phosphorus corrosion and scale inhibitor is 0.5%-0.8%, and the balance of water. Wastewater discharged after the use of the non-phosphorus corrosion and scale inhibitor does not cause phosphorus-induced eutrophication pollution to water, and is environment-friendly; the dosage of the non-phosphorus corrosion and scale inhibitor for treating water per ton is 3-10mg/L; the non-phosphorus corrosion and scale inhibitor is stable in performance and widely applied to different water qualities.