Systems and methods for washing a gas turbine compressor

Abstract

A method is provided for washing a compressor in a gas turbine. The method includes establishing a compressor fouling set point and sensing a fouling level in the compressor with a sensor. The fouling level is communicated to a control subsystem that determines a wash initiation instruction based on the fouling level and the compressor fouling set point. The wash initiation instruction is executed by initiating a wash with a fluid. A system is also disclosed including a compressor, an on-line wash system coupled to the compressor, and a compressor fouling sensor that senses a compressor fouling level. A source of washing fluid is provided, and a control subsystem that initiates a wash with washing fluid from the source of washing fluid based on a compressor fouling level.

What is claimed: 
     
         1 . A method for washing a compressor in a gas turbine, the method comprising:
 establishing a compressor fouling set point;   sensing a fouling level in the compressor with a sensor;   communicating the fouling level to a control subsystem;   determining a wash initiation instruction based on the fouling level and the compressor fouling set point; and   initiating a wash with a fluid.   
     
     
         2 . The method of  claim 1 , wherein sensing a fouling level comprises sensing a fouling level with a conductivity resistance sensor. 
     
     
         3 . The method of  claim 1 , further comprising:
 determining a time elapsed since a last wash; and   determining a duration of the last wash; and   wherein determining a wash initiation instruction comprises determining a wash initiation instruction based on the fouling level, the compressor fouling set point, the time elapsed since the last wash and the duration of the last wash.   
     
     
         4 . The method of  claim 1 , wherein initiating a wash comprises initiating a wash with a blend of water and a solvent at a predetermined blend ratio. 
     
     
         5 . The method of  claim 4 , further comprising calculating a wash duration and a wash blend ratio based on a duration of a last wash and the predetermined blend ratio of the last wash. 
     
     
         6 . The method of  claim 4 , wherein the solvent is an alcohol. 
     
     
         7 . The method of  claim 6 , further comprising interrupting the wash if the predetermined blend ratio is above a lower explosive level. 
     
     
         8 . The method of  claim 1 , further comprising interrupting the wash if a compressor temperature discharge is below a predetermined threshold. 
     
     
         9 . A system comprising:
 a compressor;   an on-line wash system coupled to the compressor;   a compressor fouling sensor that senses a compressor fouling level;   a source of washing fluid; and   a control subsystem that initiates a wash with washing fluid from the source of washing fluid based on a compressor fouling level.   
     
     
         10 . The system of  claim 9 , wherein the source of washing fluid comprises:
 a source of water;   a source of solvent; and   a mixing subsystem adapted to mix water from the source of water with solvent from the source of solvent.   
     
     
         11 . The system of  claim 10 , wherein the mixing subsystem is adapted to mix the water and solvent in a proportion based on the compressor fouling level. 
     
     
         12 . The system of  claim 10  wherein the mixing subsystem is adapted to mix the water and solvent in a proportion based on a duration of a last wash. 
     
     
         13 . The system of  claim 10 , wherein the mixing subsystem is adapted to mix the water and solvent in a proportion based on a time elapsed since a last wash. 
     
     
         14 . The system of  claim 10 , wherein the mixing subsystem comprises:
 a pump for the solvent;   a modulating valve; and   a flow sensor.   
     
     
         15 . The system of  claim 9 , further comprising a combustion system and a turbine. 
     
     
         16 . The system of  claim 15 , further comprising a load coupled to the turbine; an air inlet system coupled to the compressor; and a distributed control system. 
     
     
         17 . A method for servicing a gas turbine having a compressor; the method comprising:
 establishing a fouling level set point;   sensing a fouling level in the compressor with a fouling sensor; and   washing the compressor if the fouling level exceeds the fouling level set point.   
     
     
         18 . The method of  claim 17 , further comprising:
 determining a time elapsed since a last wash;   determining a duration of the last wash; and   determining a duration of a wash based on the time elapsed since the last wash and the duration of the last wash.   
     
     
         19 . The method of  claim 17 , wherein washing the compressor comprises washing the compressor with a blend of water and solvent. 
     
     
         20 . The method of  claim 19 , further comprising:
 determining a blend ratio of water and solvent used for a last wash; and   wherein washing the compressor with a blend of water and solvent comprises washing the compressor with a blend of water and solvent at a blend ratio of water and solvent based on the blend ratio of water and solvent used for the last wash.