Device for recovering thermal energy, independent, intended for the transfer of heat from oil to water, intended to be connected, on one hand, to the oil circuit of an oil-injected rotary compressor for the production of compressed air, in particular in parallel via a thermostatic valve, and to a water circuit requiring the supply of heat, said device for recovering thermal energy comprising: - a heat exchanger system allowing cold water at the inlet of said device to be heated using the hot oil at the inlet of said device, and hot water and cold oil to be produced at the outlet of the device, said system comprising at least one oil/water heat exchanger (51; 52, 53; 54; 55), having a primary circuit for oil and a secondary circuit (7; 71, 72) for water, and at least one circulation pump for the circulation of the water of the secondary circuit of said oil/water heat exchanger (51; 52, 53; 54; 55), - a case integrating said heat exchanger system, - at least one first connector (10; 11, 12) intended for the hot oil at the inlet of said device and at least one second connector (13; 14, 15) for the cold oil at the outlet of the device, both provided in the primary circuit of said oil/water heat exchanger (51; 52, 53; 54; 55), - a third connector intended for the cold water at the inlet of said device and a fourth connector for the hot water at the outlet of the device, and said device is intended to be connected to at least two distinct oil circuits belonging to the same number of oil-injected rotary compressors (2, 2') for the production of compressed air, and in which device said heat exchanger system comprises at least two oil/water heat exchangers (52, 53) in parallel, each of the oil/water heat exchangers (52; 53) having one said first connector (11; 12) and one said second connector (14; 15) both provided in the primary circuit of the corresponding said oil/water heat exchanger, said third connector being provided on a shared cold water inlet of the secondary circuits (71, 72) of said at least two oil/water heat exchangers (52, 53) and said fourth connector being provided on a shared hot water outlet of the secondary circuits (71, 72) of said at least two oil/water heat exchangers (52, 53), characterised in that said secondary circuits (71, 72) of said oil/water heat exchangers (52, 53) are independent of each other and are positioned in parallel, and in that said device has means for adjusting the flow rates of water in the secondary circuits (71, 72) of said oil/water heat exchangers (52, 53), comprising a flow rate adjustment valve for each secondary circuit. - a heat exchanger system allowing cold water at the inlet of said device to be heated using the hot oil at the inlet of said device, and hot water and cold oil to be produced at the outlet of the device, said system comprising at least one oil/water heat exchanger (51; 52, 53; 54; 55), having a primary circuit for oil and a secondary circuit (7; 71, 72) for water, and at least one circulation pump for the circulation of the water of the secondary circuit of said oil/water heat exchanger (51; 52, 53; 54; 55), - a case integrating said heat exchanger system, - at least one first connector (10; 11, 12) intended for the hot oil at the inlet of said device and at least one second connector (13; 14, 15) for the cold oil at the outlet of the device, both provided in the primary circuit of said oil/water heat exchanger (51; 52, 53; 54; 55), - a third connector intended for the cold water at the inlet of said device and a fourth connector for the hot water at the outlet of the device, and