Coil pipe inside and outside ice melting and cooling method and system

According to the method, through a three-section heat exchange method, low-temperature-section air conditioner chilled water (which can be directly supplied to building air conditioner water supply and the temperature is not higher than that of the air conditioner water supply), medium-temperature-section air conditioner chilled water (which is used as pre-cooling water of air conditioner return water) and medium-temperature-section air conditioner chilled water (which is used as pre-cooling water of the air conditioner return water) are sequentially extracted from an ice storage device; and the high-temperature section air conditioner cold water (the temperature is higher than that of the air conditioner return water, cannot be utilized to an air conditioner chilled water system and can be used as cooling water for re-cooling), so that the cooling capacity in the ice storage device is fully extracted, 'ten-thousand-year ice 'is completely eradicated, and the problems existing when an inner ice melting coolin