Method for cooling of the compressed gas of a compressor installation and compressor installation in which this method is applied

A method for cooling a compressed gas of a compressor installation that is provided with one or more compressor elements, whereby for a cooling of the compressed gas the method comprises the step of making use of a heat recovery circuit in the form of a closed Rankine circuit with a working medium therein that is circulated during the operation of the Rankine circuit by means of a pump in the circuit;

• one or more evaporators that act as a cooler for cooling the compressed gas;
• an expander for converting thermal energy into mechanical energy;
• a condenser that is cooled by means of a cooling circuit with a coolant that is guided through it for cooling the working medium in the condenser, wherein the method further comprises providing an additional cooler placed in series for cooling the compressed gas for at least one aforementioned evaporator that acts as a cooler for the compressed gas, whereby this additional cooler is cooled by means of a separate cooling circuit with a different coolant to the working medium of the Rankine circuit, whereby this additional cooler is configured to be able to guarantee sufficient cooling of the compressed gas by itself, for a given cooling capacity of the cooling circuit concerned of the additional cooler, when the Rankine circuit is switched off.

A compressor installation that is provided with one or more compressor elements and with a cooling to cool the gas compressed by the compressor elements, whereby this cooling is formed by a heat recovery circuit that is realised as a closed ‘Rankine circuit’ with a pump, a working medium that circulates in the Rankine circuit during operation of the Rankine circuit by means of the pump;

• one or more evaporators through which the compressed gas to be cooled is guided for cooling the compressed gas;
• an expander for converting thermal energy into mechanical energy;
• and a condenser that is connected to a cooling circuit with a coolant that is guided through it to cool the working medium in the condenser, wherein the compressor installation comprises at least one additional cooler that is incorporated in series with an aforementioned evaporator in the gas flow of the compressed gas to be cooled, whereby this at least one additional cooler is connected to a cooling circuit with a different coolant to the working medium of the Rankine circuit, and whereby this additional cooler is configured to be able to guarantee sufficient cooling of the compressed gas by itself, for a given cooling capacity of the cooling circuit, when the Rankine circuit is switched off.