Cooling system and method

A method of mixing concrete in a system in which an aggregate stream is carried by a conveyor device toward a mixing chamber in which the aggregate is mixed to form the concrete, the method comprising:

• controlling, by a computerized liquid nitrogen control system, a valve of an aggregate cooling system to control a supply flow of liquid nitrogen from a liquid nitrogen storage tank to a dispensing head via a piping system, wherein the dispensing head is positioned above the conveyor device;
• venting, from the piping system, nitrogen gas generated by evaporation of the liquid nitrogen within the piping system, wherein the venting facilitates an uninterrupted flow of the liquid nitrogen to the dispensing head, and wherein the venting comprises causing the computerized liquid nitrogen control system to open a vent valve in response to actuation of a sensor in electrical communication with the computerized liquid nitrogen control system;
• and
• dispensing the liquid nitrogen form the dispensing head onto the aggregate stream while the aggregate stream is carried by the conveyor device toward the mixing chamber;
• wherein the dispensing head, the piping system, and the conveyor device are positioned outdoors and exposed to ambient environmental temperature.