Method and device for driving liquid from a liquid separator

The method of separating the liquid phase from the mixture of compressed gas and liquid and returning the separated liquid phase to the compressor in a liquid injected system, said method comprising:

• a. passing a stream of the compressed gas and liquid mixture from the compressor into a closed container;
• b. subjecting said mixture to a primary separation step in said container, whereby a major portion of the liquid phase is separated off and collected at the bottom of the container and maintained under the pressure prevailing thereon, passing a stream of the thus separated liquid as primary injection liquid from said container through a primary passage to the compressor by the pressure prevailing in the container;
• c. subjecting the partly separated mixture to a secondary separating zone within said container, from which the liquid-freed compressed gas is discharged while the separated-off liquid is collected under the prevailing pressure in said secondary separating zone at a location spaced from the liquid level in said container;
• d. passing the stream of the liquid collected in said secondary separating step by the pressure prevailing in said secondary separating zone in a passage merging with said primary passage and injecting the merged liquid streams under controlled force into the compressor through a common passage.