Abstract: The invention relates to a group of heat exchangers for compressed gas refrigeration dryers, in which the heat exchangers (20,30) comprise a series of finned, closely spaced plates (21, 31), creating a series of passages for the countercurrent flow of fluids, and in which the gas/gas heat exchanger (20) is positioned beside the evaporator (30), so that an outlet zone (28) of a pre-cooling section (22) of the gas/gas heat exchanger (20) directs the mixture of compressed gases directly to an inlet zone (36) of a cooling section (32) of the evaporator (30).

Abstract: A control system for compressed gas refrigeration dryers comprises a gas/gas exchanger (7), suitable for cooling a mixture of compressed gas (M), using an outgoing gas (K) from an air condenser (8), and at least one refrigeration cycle (11), which includes an evaporator (6); each of said refrigeration cycles (11) comprises at least two compressors (1, 2), connected in parallel to each other and each connected in series to at least one non-return valve (3), said compressors (1, 2) being further connected, by means of at least one duct (13), so that the respective zones containing the lubricating oil are connected to each other. It also comprises at least one refrigeration capacity variation system suitable for driving the contemporary or separate functioning of said compressors (1, 2), with the possibility of controlling the motor rotation of at least one of the compressors in relation to the cooling load to be transferred to the evaporator (6).