Where is the heat finally rejected in a refrigeration system with a draft cooling tower and an economizer?

In a refrigeration system that utilizes a draft cooling tower and an economizer, the heat is ultimately rejected as heat of evaporation in the cooling tower. The cooling tower plays a critical role in dissipating heat from the refrigerant circuit.

When the refrigerant absorbs heat from the space being cooled, it transitions from a liquid to a gas. The cooling tower facilitates the cooling of this gas by allowing it to expel heat into the atmosphere, primarily through the process of evaporation. As water circulates through the cooling tower, it absorbs heat from the refrigerant line and, as it evaporates, takes this heat away, effectively lowering the temperature of the water that can then be reused in the system.

This process is more efficient because it utilizes the natural heat transfer principles associated with water evaporation rather than relying solely on mechanical methods. This method of heat rejection is particularly advantageous in improving the overall efficiency of the refrigeration system. The other options do not directly point to the heat rejection mechanism used in this scenario.