Heat exchanger apparatus for a recirculation loop and related methods and systems

A method for heat transfer and temperature control of a process liquid comprising:

• circulating a liquid from a source of liquid into a plurality of heat transfer components contained within a first housing and then out of the heat transfer components to the source such that at least a portion of the liquid that is returned to the source from the plurality of heat transfer components is delivered again to the plurality of heat transfer components;
• sensing the temperature of the circulating liquid;
• automatically controlling delivery of pressurized gas to a first gas separator that is located within the first housing based on a sensed temperature of the liquid;
• separating the pressurized gas by vortex expansion into a first gas stream at a first temperature and a second gas stream at a second temperature that is different from the first temperature, wherein separating the pressurized gas is performed within the first gas separator, and wherein the first gas separator is encircled by the plurality of heat transfer components;
• and
• delivering the first gas stream into contact with the plurality of heat transfer components and then out of the first housing while limiting contact of the second gas stream with the plurality of heat transfer components.