Arrangement for controlling the flow of a coolant fluid in a compressor

Arrangement for controlling the flow of a coolant fluid in a compressor comprising:

• a coolant-fluid inlet for coolant fluid discharged from the compressor and a coolant-fluid outlet for returning the coolant fluid to the compressor;
• a fluid cooler through which a proportion of the coolant fluid can be diverted to be cooled;
• a system-control actuator which controls the proportion of coolant fluid that is injected into the compressor on the basis of system parameters including the temperature of the coolant fluid, by fluid-control means;
• a fluid control device;
• and
• a summer-/winter-operation actuator, which in a summer position takes priority over the system-control actuator to limit the action of the system-control actuator in one direction such that when the summer-/winter-operation actuator is activated, the proportion of coolant fluid that is injected into the compressor is increased or is diminished by the fluid-control device.

A method of controlling flow of a coolant fluid through a compressor for adjusting a temperature of a process fluid, comprising the steps of directing the coolant fluid discharged from the compressor, when necessary for cooling, through a fluid cooler for cooling the coolant fluid;

• and controlling at least one of an amount of coolant fluid injected into the compressor and a proportion of the coolant fluid directed through the fluid cooler on basis of system parameters including a temperature of the coolant fluid,
• wherein a reduction of the temperature of the process fluid is effected by at least one of increasing an amount of coolant fluid injected into the compressor and increasing of a proportion of the coolant fluid directed through the fluid cooler,
• wherein an increase of the temperature of the process fluid is effected by at least one of reducing an amount of coolant fluid injected into the compressor and reducing of a proportion of the coolant fluid directed through fluid cooler,
• wherein a winter operation is conducted at low atmospheric temperatures, and a summer operation is conducted at high atmospheric temperatures,
• wherein in order to prevent a maximal temperature of the process fluid in a consuming apparatus from exceeding a predetermined threshold at the high atmospheric temperatures and to prevent condensation or ice formation in the consuming apparatus and conduits connecting the consuming apparatus with the compressor at the low atmospheric temperatures, during the summer operation, lower temperatures of process fluid are controlled as during the winter operation;
• and
• wherein a change-over between the winter and summer operations is effected one of manually and automatically by a summer/winter operation actuator that functions dependent on an atmospheric temperature.