Use of refrigeration loops to chill inlet air to gas turbine

Abstract

As described herein, a method and system for operating a refrigeration system are provided. In the present methods and systems, a portion of the refrigerant from the refrigeration system is used for reducing the temperature of inlet air entering the gas turbine. The refrigeration system disclosed herein can be used for LNG production, air separation, food storage, or ice-making.

1 . An integrated system for refrigeration comprising:
 (a) a refrigeration system comprising a refrigeration loop for air-chilling;   (b) a gas turbine for driving a compressor for the refrigeration system;   (c) a heat exchanger for consuming a portion of refrigerant from the refrigeration system and cooling a heat transfer fluid; and   (d) a second heat exchanger for reducing the temperature of inlet air entering the gas turbine with the heat transfer fluid.   
     
     
         2 . The integrated system of  claim 1 , wherein the refrigeration is for LNG production, air separation, food storage, or ice-making. 
     
     
         3 . The integrated system of  claim 1 , wherein the refrigerant comprises methane, ethane, propane, ammonia, a hydrofluorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a bromofluorocarbon, a bromochlorofluorocarbon, or any combination thereof. 
     
     
         4 . The integrated system of  claim 1 , wherein a gain in energy efficiency by reducing the temperature of the inlet air entering the gas turbine compensates for an amount of energy required for chilling and consuming the portion of refrigerant in step (c). 
     
     
         5 . The integrated system of  claim 1 , wherein the heat transfer fluid comprises methanol, ethanol, a glycol and water mixture, or any combination thereof. 
     
     
         6 . The integrated system of  claim 1 , comprising a single stage, two stage or three stage refrigeration loop. 
     
     
         7 . The integrated system of  claim 1 , wherein the portion of the refrigerant consumed is in a range from 5% to 25% by weight. 
     
     
         8 . The integrated system of  claim 1 , wherein the portion of the refrigerant consumed is in a range from 10% to 20% by weight. 
     
     
         9 . The integrated system of  claim 1 , wherein the second heat exchanger comprises a cooling coil at an inlet of the gas turbine. 
     
     
         10 . The integrated system of  claim 1 , wherein the temperature of the inlet air entering the gas turbine is reduced by 10 to 40° F. from ambient temperature. 
     
     
         11 . The integrated system of  claim 1 , wherein the temperature of the inlet air entering the gas turbine is reduced from an ambient temperature in a range from about 60 to about 120° F. to a temperature in a range from about 45 to about 55° F. 
     
     
         12 . The integrated system of  claim 1 , wherein the temperature of the inlet air entering the gas turbine is reduced to a temperature in a range from about 45 to about 55° F. 
     
     
         13 . The integrated system of  claim 1 , wherein an efficiency of the gas turbine is increased by at least 3% by reducing the temperature of the inlet air from 90 to 50° F. 
     
     
         14 . The integrated system of  claim 1 , wherein the refrigerant prior to reducing the temperature of the inlet air is at a temperature of from about −45 to about 45° F. 
     
     
         15 . The integrated system of  claim 1 , wherein the heat transfer fluid prior to reducing the temperature of the inlet air is at a temperature of from about −45 to about 30° F. 
     
     
         16 . The integrated system of  claim 1 , wherein the refrigerant comprises propane and the heat transfer fluid comprises methanol. 
     
     
         17 . An integrated method of maximizing gas turbine output for a refrigeration loop comprising:
 (a) operating a refrigeration loop for chilling processes;   (b) operating a gas turbine to drive a compressor for a the refrigeration loop;   (c) gasifying a portion of refrigerant from the refrigeration system; and   (d) reducing the temperature of inlet air entering the gas turbines by exchanging heat with the gasified portion of refrigerant either directly or indirectly.   
     
     
         18 . The integrated method of  claim 17 , wherein the refrigeration is for LNG production, air separation, food storage, or ice-making. 
     
     
         19 . The integrated method of  claim 17 , comprising a single stage, two stage, or three stage refrigeration loop. 
     
     
         20 . The integrated method of  claim 17 , wherein the refrigerant comprises methane, ethane, propane, ammonia, a hydrofluorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a bromofluorocarbon, a bromochlorofluorocarbon, or any combination thereof. 
     
     
         21 . The integrated method of  claim 17 , wherein a gain in energy efficiency by reducing the temperature of the inlet air entering the gas turbine compensates for an amount of energy required for chilling and consuming the portion of refrigerant in step (c). 
     
     
         22 . The integrated method of  claim 17 , wherein the temperature of inlet air is reduced by exchanging heat indirectly with the regasified portion of refrigerant using an intermediate heat transfer fluid. 
     
     
         23 . The integrated method of  claim 22 , wherein the heat transfer fluid comprises methanol, ethanol, a glycol and water mixture, or any combination thereof. 
     
     
         24 . The integrated method of  claim 17 , wherein the temperature of the inlet air entering the gas turbine is reduced by 10 to 40° F. from ambient temperature. 
     
     
         25 . The integrated method of  claim 17 , wherein the temperature of the inlet air entering the gas turbine is reduced from an ambient temperature in a range from about 60 to about 120° F. to a temperature in a range from about 45 to about 55° F. 
     
     
         26 . The integrated method of  claim 17 , wherein an efficiency of the gas turbine is increased by at least 3% by reducing the temperature of the inlet air from 90 to 50° F. 
     
     
         27 . The integrated method of  claim 17 , further comprising recycling at least a portion of the consumed refrigerant to the refrigeration loop. 
     
     
         28 . The method of  claim 17 , further comprising a step of collecting water condensed from reducing the temperature of the inlet air. 
     
     
         29 . An integrated method for operating a liquefied natural gas (LNG) plant, the method comprising:
 (i) cooling and condensing a natural gas stream in a refrigeration system to produce liquefied natural gas (LNG);   (ii) operating a gas turbine to drive a compressor for the refrigeration system;   (iii) regasifying a portion of the LNG;   (iv) consuming a portion of the refrigerant from the refrigeration system; and   (iv) reducing the temperature of inlet air entering the gas turbine by exchanging heat with the regasified portion of the LNG and with the consumed portion of the refrigerant directly or indirectly.   
     
     
         30 . The integrated method of  claim 29  further comprising supplying at least a portion of the regasified portion of the LNG to an outlet pipeline.