Temperature controlled nitrogen generation system

Abstract

A nitrogen generation system includes a heat exchanger for receiving supply air and cooling air and providing temperature conditioned supply air, a flow control valve for controlling a flow of the cooling air through the heat exchanger, and an air separation module for receiving the temperature conditioned supply air and generating nitrogen-enriched air. The nitrogen generation system also includes a sensor for measuring a parameter of the nitrogen-enriched air selected from the group consisting of a temperature, a flow rate, an oxygen concentration, and combinations thereof, and a controller connected to the sensor and the flow control valve for controlling the flow of the cooling air through the heat exchanger based on the parameter of the nitrogen-enriched air measured by the sensor.

1 . A nitrogen generation system comprising:
 a mixer for receiving supply air and cooling air and providing temperature conditioned supply air;   a first flow control valve for controlling a flow of the cooling air into the mixer;   an air separation module for receiving the temperature conditioned supply air and generating nitrogen-enriched air;   a first sensor upstream of the air separation module for measuring a parameter of the temperature conditioned supply air selected from the group consisting of a temperature, a flow rate, an oxygen concentration, and combinations thereof;   a second sensor downstream of the air separation module for measuring a parameter of the nitrogen enriched air selected from the group consisting of a temperature, a flow rate, an oxygen concentration, and combinations thereof, wherein the second sensor is connected to the controller; and   a controller connected to the first sensor, the second sensor, and the first flow control valve, wherein the controller is for controlling the flow of the cooling air through the mixer based on the parameter of the temperature conditioned supply air measured by the first sensor, and for controlling the flow of the temperature conditioned supply air based on the parameter of the nitrogen enriched air measured by the second sensor.   
     
     
         2 . The nitrogen generation system of  claim 1 , wherein the supply air is bleed air and the cooling air is ram air. 
     
     
         3 . The nitrogen generation system of  claim 1 , wherein the air separation module comprises a membrane. 
     
     
         4 . The nitrogen generation system of  claim 3 , wherein the membrane is made of a polymer selected from the group consisting of poly(1-trimethylsilyl-1-propyne), Teflon, silicone rubber, poly(4-methyl-1-pentene), poly(phenylene oxide), ethyl cellulose, polyimide, polysulfone, polyaramide, tetrabromo bis polycarbonate, and combinations thereof. 
     
     
         5 . The nitrogen generation system of  claim 1 , and further comprising a jacket surrounding the air separation module and a second flow control valve connected to the controller. 
     
     
         6 . The nitrogen generation system of  claim 1 , wherein the supply air entering the mixer have a pressure between about 30 psi and about 40 psi. 
     
     
         7 . The nitrogen generation system of  claim 1 , wherein the cooling air entering the mixer have a pressure between about 30 psi and about 40 psi. 
     
     
         8 . The nitrogen generation system of  claim 1 , wherein the first flow control valve can 
     
     
         9 . The nitrogen generation system of  claim 1 , wherein the controller further controls the flow of supply air based on the parameter of the temperature conditioned supply air measured by the first sensor. 
     
     
         10 . A method of generating nitrogen-enriched air, the method comprising:
 cooling supply air with cooling air to produce temperature conditioned supply air by mixing the flow of the cooling air and the supply air;   flowing a first flow of the temperature conditioned supply air through an air separation module to generate nitrogen-enriched air;   measuring a parameter of the nitrogen-enriched air selected from the group consisting of a temperature, a flow rate, an oxygen concentration, and combinations thereof;   controlling a flow of the cooling air based on the parameter of the nitrogen-enriched air.   
     
     
         11 . The method of  claim 10 , wherein the cooling air is at a pressure between about 30 psi and about 40 psi. 
     
     
         12 . The method of  claim 10 , wherein the supply air is a pressure between about 30 psi and about 40 psi 
     
     
         13 . The method of  claim 10 , wherein the temperature of the supply air is between 148 degrees Celsius and 233 degrees Celsius. 
     
     
         14 . The method of  claim 10 , wherein the temperature of the cooling air is between −46 degrees Celsius and 43.4 degrees Celsius. 
     
     
         15 . The method of  claim 10 , wherein the temperature of the nitrogen-enriched air is between 15 degrees Celsius and 93.4 degrees Celsius. 
     
     
         16 . The method of  claim 10 , and further comprising measuring a parameter of the temperature conditioned supply air selected from the group consisting of a temperature, a flow rate, an oxygen concentration, and combinations thereof, wherein the second sensor is connected to the controller. 
     
     
         18 . The method of  claim 10 , wherein the oxygen concentration of the nitrogen-enriched air is less than 12 percent. 
     
     
         19 . The method of  claim 10 , further comprising generating oxygen enriched air simultaneously with generating nitrogen enriched air in the air separation module. 
     
     
         20 . The method of  claim 19 , further comprising sending the oxygen enriched air overboard.