System and method for storing and dispensing fuel and ballast fluid

Abstract

A system for storing and dispensing fuel and a ballast fluid is disclosed. The system may be employed in a vehicle or facility having a power plant. Fuel and ballast fluid may be stored cryogenically in a liquid phase and dispensed to the vapor phase. The system may employ a thermal and volumetric compensatory arrangement wherein fuel dispensed from storage for use in a power plant is used as a heat exchange medium (refrigerant) for ballast fluid received for storage; during refueling, ballast fluid stored in the vehicle or facility may be dispensed and used as a refrigerant for fuel being stored in the vehicle in space made available by the dispensed ballast fluid. The fuel may be natural gas with a main component of methane; the ballast fluid may be a fluid obtainable from ambient environmental air, such as nitrogen or oxygen. The fuel and ballast fluid may be conditioned so that the respective boiling points are approximately equal. The system may employ a heat transfer system with a microchannel heat exchanger.

1 - 133 . (canceled) 
     
     
         134 . A method of storing and dispensing fuel and a ballast fluid comprising the steps of:
 providing fuel in storage in liquid phase;   providing ballast fluid in storage in liquid phase;   dispensing fuel from storage through a heat transfer system in which the fuel is used as a refrigerant for ballast fluid received for storage through the heat transfer system so that the fuel is converted to vapor phase for dispensing as the ballast fluid is converted to liquid phase for storage.   
     
     
         135 . The method of  claim 134  further comprising the step of dispensing ballast fluid from storage through a heat transfer system in which the ballast fluid is used as a refrigerant for fuel received for storage through the heat transfer system so that fuel is converted to liquid phase for storage as the ballast fluid is converted to vapor phase for dispensing. 
     
     
         136 . The method of  claim 134  further comprising the step of conditioning the fuel for storage. 
     
     
         137 . The method of  claim 134  further comprising the step of conditioning the ballast fluid for storage. 
     
     
         138 - 141 . (canceled) 
     
     
         142 . The method of  claim 134  wherein the fuel and the ballast fluid are stored at a cryogenic temperature. 
     
     
         143 . The method of  claim 134  wherein the fuel and the ballast fluid are stored at approximately the same temperature. 
     
     
         144 . The method of  claim 134  wherein the fuel is stored at a first pressure and the ballast fluid is stored at a second pressure and the first pressure is lower than the second pressure. 
     
     
         145 . The method of  claim 134  further comprising dispensing ballast fluid from storage through a heat exchange where the ballast fluid is used as a refrigerant for fuel received for storage. 
     
     
         146 . The method of  claim 134  further comprising the step of obtaining ballast fluid for storage by conditioning atmospheric air. 
     
     
         147 . (canceled) 
     
     
         148 . The method of  claim 134  wherein the fuel comprises methane. 
     
     
         149 . The method of  claim 134  wherein the fuel comprises natural gas. 
     
     
         150 . The method of  claim 134  wherein the ballast fluid comprises a fluid obtainable from atmospheric air. 
     
     
         151 . The method of  claim 134  wherein the ballast fluid comprises nitrogen. 
     
     
         152 . The method of  claim 134  wherein the ballast fluid comprises oxygen. 
     
     
         153 . The method of  claim 134  wherein the ballast fluid comprises nitrogen and oxygen. 
     
     
         154 . The method of  claim 134  wherein the fuel is stored at a temperature of less than approximately 95 degrees K and at a pressure of less than approximately 0.21 bar. 
     
     
         155 . The method of  claim 134  wherein the ballast fluid is stored at a temperature of less than approximately 95 degrees K and at a pressure of greater than approximately 5 bar. 
     
     
         156 . The method of  claim 134  wherein the fuel and the ballast fluid are stored at a temperature that is approximately equal. 
     
     
         157 . The method of  claim 134  wherein the fuel is stored at a first pressure and the ballast fluid is stored at a second pressure so that the boiling point of the fuel and the boiling point of the ballast fluid are approximately equal. 
     
     
         158 . The method of  claim 134  wherein the step of dispensing fuel from storage through a heat transfer system comprises the step of supplying the fuel to a microchannel heat exchanger. 
     
     
         159 . The method of  claim 134  wherein the step of dispensing fuel from storage through a heat transfer system comprises the step of supplying the fuel to a counterflow heat exchanger. 
     
     
         160 - 163 . (canceled) 
     
     
         164 . The method of  claim 134  wherein the fuel and the ballast fluid are matched so that the heat of vaporization of the fuel is approximately equal to the heat of condensation of the ballast fluid. 
     
     
         165 . The method of  claim 134  wherein fuel and the ballast fluid are matched so that the heat of vaporization of the ballast fluid is approximately equal to the heat of condensation of the fuel. 
     
     
         166 . The method of  claim 134  wherein the heat of condensation of the fuel is substantially the same as the heat of vaporization of the ballast fluid. 
     
     
         167 . The method of  claim 134  wherein the heat of condensation of the ballast fluid is substantially the same as heat of vaporization of the fuel. 
     
     
         168 . The method of  claim 134  further comprising storing the fuel and storing the ballast fluid in a common volume so that when a volume of fuel is dispensed a volume of ballast fluid is stored and wherein the volume of fuel is approximately equal to the volume of ballast fluid. 
     
     
         169 - 190 . (canceled) 
     
     
         191 . The method of  claim 134  wherein the amount of the fuel dispensed from a fuel chamber and the amount of the ballast fluid supplied to a ballast fluid chamber are matched so that energy required to evaporate the fuel from a liquid to a vapor gas is approximately the same as the energy required to condense the ballast fluid from a vapor to a liquid. 
     
     
         192 . The method of  claim 134  further comprising a reserve chamber from which liquid ballast fluid is available for use as a refrigerant for fuel. 
     
     
         193 . The method of  claim 134  wherein the ballast fluid is used as a refrigerant to maintain the fuel in the fuel chamber in liquid phase. 
     
     
         194 . The method of  claim 134  further comprising the step of maintaining a fuel chamber storing the liquid fuel at a first pressure and a ballast fluid chamber storing the liquid ballast fluid at a second pressure. 
     
     
         195 . The method of  claim 134  wherein a fuel chamber for storing the liquid fuel and a ballast fluid chamber for storing the liquid ballast fluid are adjacent so that the ballast fluid serves as a refrigerant for the fuel during storage. 
     
     
         196 - 204 . (canceled) 
     
     
         205 . The method of  claim 134  further comprising the step of conditioning the fuel and wherein conditioning the fuel comprises adjusting the pressure of a fuel storage chamber to a first pressure. 
     
     
         206 . The method of  claim 134  further comprising the step of conditioning the ballast fluid and wherein conditioning the fuel comprises adjusting the pressure of a ballast fluid storage chamber to a second pressure. 
     
     
         207 - 213 . (canceled) 
     
     
         214 . The method of  claim 134  wherein the liquid fuel is stored within a first tank and the liquid ballast fluid is stored within a second tank separate from the first tank. 
     
     
         215 . The method of  claim 134  wherein the ballast fluid is dispensed to the atmosphere. 
     
     
         216 - 245 . (canceled)