System and method for cryogenic gasification using ambient air gasifier

The invention provides a gasification system and a control method. Liquid refrigerant is provided to a first ambient air vaporizer (AAV) unit. A liquid refrigerant is provided to the second AAV unit when the output superheated vapor temperature is less than a threshold. When greater than or equal to a threshold, it is determined whether the second AAV unit has been defrosted. When the defrosting has been performed, a liquid refrigerant is provided to the second AAV unit. When the defrosting is not performed, whether the first AAV unit is frozen or not is determined. When no ice is formed, it is re-determined whether the superheated vapor temperature is less than a threshold. When icing, it is determined whether the current environmental condition facilitates defrosting of the second AAV unit. A liquid refrigerant is provided to the second set of AAV units when defrost of the second AAV unit is not facilitated. When defrost of the second AAV unit is facilitated, it is re-determined whether the superheated vapo