Compressor system, subsea production system provided therewith, and compressor cleaning method

Abstract

A compressor system includes a compressor ( 50 ) configured to compress a gas, a compressed gas circulation unit ( 52 ) in which a gas compressed by the compressor ( 50 ) circulates, a hydrate anti freezing agent supply unit ( 53 ) configured to supply a hydrate anti freezing agent for preventing hydration of the gas to the compressed gas circulation unit ( 52 ), a compressor hydrate anti freezing agent supply unit ( 54 ) configured to supply part of the hydrate anti freezing agent supplied from the hydrate anti freezing agent supply unit ( 53 ) to the compressor ( 50 ), and a pressure changing unit ( 59 ) configured to change a pressure of the hydrate anti freezing agent inside the compressor ( 50 ).

1 . A compressor system comprising:
 a compressor configured to compress a gas;   a compressed gas circulation unit in which a gas compressed by the compressor circulates;   a hydrate anti freezing agent supply unit configured to supply a hydrate anti freezing agent for preventing hydration of the gas to the compressed gas circulation unit;   a compressor hydrate anti freezing agent supply unit configured to supply part of the hydrate anti freezing agent supplied from the hydrate anti freezing agent supply unit to the compressor; and   a pressure changing unit configured to change a pressure of the hydrate anti freezing agent inside the compressor.   
     
     
         2 . The compressor system according to  claim 1 , comprising
 a gas discharge unit configured to discharge the gas inside the compressor,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent to the compressor from which the gas is discharged by the gas discharge unit.   
     
     
         3 . The compressor system according to  claim 1 , comprising
 a storage unit configured to store the hydrate anti freezing agent in the compressor,   wherein the pressure changing unit changes a pressure of the hydrate anti freezing agent that is stored by the storage unit.   
     
     
         4 . The compressor system according to  claim 1 , comprising
 a control unit configured to perform supply control such that, when predetermined conditions are satisfied, the compressor hydrate anti freezing agent supply unit starts supply of the hydrate anti freezing agent to the compressor.   
     
     
         5 . The compressor system according to  claim 4 ,
 wherein the control unit includes   a first reference determination unit configured to determine whether a difference between characteristic values of the gas on an inlet side of the compressor and an outlet side of the compressor satisfies a predetermined first reference, and   a supply start instruction unit configured to send an instruction to the compressor hydrate anti freezing agent supply unit to start supply of the hydrate anti freezing agent to the compressor when the first reference determination unit determines that the first reference is satisfied.   
     
     
         6 . The compressor system according to  claim 1 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent heated by the heating unit to the compressor.   
     
     
         7 . The compressor system according to  claim 5 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the control unit includes   a second reference determination unit configured to determine whether a difference between characteristic values of the gas on the inlet side of the compressor and the outlet side of the compressor satisfies a predetermined second reference after supply of the hydrate anti freezing agent to the compressor starts, and   a heat supply instruction unit configured to send an instruction to the compressor hydrate anti freezing agent supply unit to supply the hydrate anti freezing agent heated by the heating unit to the compressor when the second reference determination unit determines that the second reference is satisfied.   
     
     
         8 . A subsea production system comprising:
 the compressor system according to  claim 1 ; and   a separator configured to separate a production fluid drawn from a production well into the gas and a liquid and supply the result to the compressor.   
     
     
         9 . A compressor cleaning method in which a compressor configured to compress a gas is cleaned, comprising:
 a gas discharging process in which the gas inside the compressor is discharged;   a compressor hydrate anti freezing agent supply process in which part of a hydrate anti freezing agent for preventing hydration of the gas supplied to a compressed gas circulation unit in which a gas compressed by the compressor circulates is supplied to the compressor from which the gas is discharged in the gas discharging process; and   a pressure changing process in which a pressure of the hydrate anti freezing agent in the compressor is changed.   
     
     
         10 . The compressor cleaning method according to  claim 9 , comprising
 a storing process in which the hydrate anti freezing agent is stored in the compressor,   wherein, in the pressure changing process, a pressure of the hydrate anti freezing agent stored in the storing process is changed.   
     
     
         11 . The compressor cleaning method according to  claim 9 , comprising
 a first reference determining process in which it is determined whether a difference between characteristic values of the gas on an inlet side of the compressor and an outlet side of the compressor satisfies a predetermined first reference, and   a supply start process in which, when it is determined in the first reference determining process that the first reference is satisfied, supply of the hydrate anti freezing agent to the compressor starts.   
     
     
         12 . The compressor cleaning method according to  claim 11 , comprising
 a second reference determining process in which, after supply of the hydrate anti freezing agent to the compressor starts, it is determined whether a difference between characteristic values of the gas on the inlet side of the compressor and the outlet side of the compressor satisfies a predetermined second reference, and   a heat supply process in which, when it is determined in the second reference determining process that the second reference is satisfied, the heated hydrate anti freezing agent is supplied to the compressor.   
     
     
         13 . The compressor system according to  claim 2 , comprising
 a storage unit configured to store the hydrate anti freezing agent in the compressor,   wherein the pressure changing unit changes a pressure of the hydrate anti freezing agent that is stored by the storage unit.   
     
     
         14 . The compressor system according to  claim 2 , comprising
 a control unit configured to perform supply control such that, when predetermined conditions are satisfied, the compressor hydrate anti freezing agent supply unit starts supply of the hydrate anti freezing agent to the compressor.   
     
     
         15 . The compressor system according to  claim 3 , comprising
 a control unit configured to perform supply control such that, when predetermined conditions are satisfied, the compressor hydrate anti freezing agent supply unit starts supply of the hydrate anti freezing agent to the compressor.   
     
     
         16 . The compressor system according to  claim 2 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent heated by the heating unit to the compressor.   
     
     
         17 . The compressor system according to  claim 3 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent heated by the heating unit to the compressor.   
     
     
         18 . The compressor system according to  claim 4 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent heated by the heating unit to the compressor.   
     
     
         19 . The compressor system according to  claim 5 , comprising
 a heating unit configured to heat the hydrate anti freezing agent,   wherein the compressor hydrate anti freezing agent supply unit supplies the hydrate anti freezing agent heated by the heating unit to the compressor.   
     
     
         20 . A subsea production system comprising:
 the compressor system according to  claim 2 ; and   a separator configured to separate a production fluid drawn from a production well into the gas and a liquid and supply the result to the compressor.