Compressor system for natural gas, method of compressing natural gas and plant using them

Abstract

A compressor system including a driver machine, for example a motor or a turbine, an epicyclic gearbox, and a centrifugal compressor, wherein the driver machine, the epicyclic gearbox, and the centrifugal compressor are connected in train configuration, i.e. the output rotary member of the driver machine is coupled to the input rotary member of the epicyclic gearbox and the output rotary member of the epicyclic gearbox is coupled to the input rotary member of the centrifugal compressor. The gear ratio of the epicyclic gearbox is greater than one, typically much more than one, thus increasing the rotation speed from input to output.

What is claimed is: 
     
         1 . A compressor system for natural gas, the compressor system comprising:
 a driver machine comprising a first output rotary member;   an epicyclic gearbox comprising a first input rotary member and a second output rotary member, the epicyclic gearbox having a gear ratio greater than one thus increasing the rotation speed from input to output; and   a first centrifugal compressor configured to compress natural gas, the first centrifugal compressor comprising a second input rotary member;   wherein the first output rotary member of the driver machine is coupled to the first input rotary member of the epicyclic gearbox, and   wherein the second output rotary member of the epicyclic gearbox is coupled to the second input rotary member of the centrifugal compressor.   
     
     
         2 . The compressor system of  claim 1 , wherein the epicyclic gearbox is multi-stage, and/or compound type. 
     
     
         3 . The compressor system of  claim 1 , wherein the driver machine is an electric motor or a gas turbine or a steam turbine. 
     
     
         4 . The compressor system of  claim 1 , wherein the gearbox is mounted on the driver machine, or on foot, or on the driver machine and on foot. 
     
     
         5 . The compressor system of  claim 1 , further comprising a second centrifugal compressor configured to compress natural gas, wherein the first centrifugal compressor and the second centrifugal compressor are connected in train configuration to the first output rotary member of the driver machine. 
     
     
         6 . A method of compressing natural gas through a centrifugal compressor, the method comprising:
 driving the centrifugal compressor through an epicyclic gearbox using a driver machine, wherein the epicyclic gearbox has a gear ratio greater than one.   
     
     
         7 . The method of  claim 6 , wherein the gear ratio of the epicyclic gearbox is in the range from 5 to 20. 
     
     
         8 . The method of  claim 6 , wherein the driver machine comprises an output rotary member, and wherein the output rotary member is configured to drive an at least two or more centrifugal compressors at different rotation speeds. 
     
     
         9 . The method of  claim 6 , wherein the driver machine is operated at a variable rotation speed. 
     
     
         10 . A plant comprising:
 a compressor system for gas, wherein the compressor system comprises:
 a driver machine comprising a first output rotary member; 
 an epicyclic gearbox comprising a first input rotary member and a second output rotary member, wherein the epicyclic gearbox has a gear ratio greater than one thus increasing the rotation speed from input to output; and 
 a centrifugal compressor configured to compress gas, the centrifugal compressor comprising a second input rotary member; 
 wherein the first output rotary member of the driver machine is coupled to the first input rotary member of the epicyclic gearbox, and 
 wherein the second output rotary member of the epicyclic gearbox is coupled to the second input rotary member of the centrifugal compressor. 
   
     
     
         11 . The compressor system of  claim 2 , wherein the epicyclic gearbox is two stage. 
     
     
         12 . The plant of  claim 10 , wherein the epicyclic gearbox is multi-stage, and/or compound type. 
     
     
         13 . The plant of  claim 10 , wherein the driver machine is an electric motor or a gas turbine or a steam turbine. 
     
     
         14 . The plant of  claim 10 , wherein the gearbox is mounted on the driver machine, or on foot, or on the driver machine and on foot. 
     
     
         15 . The plant of  claim 10 , further comprising a second centrifugal compressor configured to compress natural gas, wherein the first centrifugal compressor and the second centrifugal compressor are connected in train configuration to the first output rotary member of the driver machine. 
     
     
         16 . The plant of  claim 10 , wherein the epicyclic gearbox is two stage.