Temperature compensation of deepwater accumulators

Abstract

The method of providing an accumulator for the storage of pressurized liquids by the use of a pressurized gas, comprising providing for the storage of said pressurized gas, providing for the storage of said pressurized liquids which are pressurized by said pressurized gas, moving said accumulator to a location of lower environmental temperatures, and increasing the temperature of said pressurized gas to increase the pressure of said gas and therefore to increase the pressure of said pressurized liquid.

1 . The method of providing an accumulator for the storage of pressurized liquids by the use of a pressurized gas, comprising 
 providing for the storage of said pressurized gas,    providing for the storage of said pressurized liquids which are pressurized by said pressurized gas,    moving said accumulator to a location of lower environmental temperatures, and    increasing the temperature of said pressurized gas to increase the pressure of said gas and therefore to increase the pressure of said pressurized liquid.    
   
   
       2 . The invention of  claim 1 , further comprising said pressurized gas and said pressurized liquid are in separated chambers.  
   
   
       3 . The method of  claim 1 , further comprising using electricity to increase the temperature of said pressurized gas.  
   
   
       4 . The method of  claim 3 , further comprising using the umbilical power cable of a subsea blowout preventer stack to provide the electric power to increase the temperature of said gas.  
   
   
       5 . The method of  claim 1 , further comprising that said location of lower environmental temperatures is near the floor of an ocean.  
   
   
       6 . The method of  claim 1 , further comprising that said location of lower environmental temperatures is in outer space.  
   
   
       7 . The method of  claim 5 , further comprising that the temperature of said pressurized gas in the subsea or outer space location is increased to a temperature higher than the temperature of the environment.  
   
   
       8 . The method of recharging the pressure of an accumulator with a pressurized gas pressurizing a liquid comprising, 
 allowing the temperature of said gas to cool to a first temperature and liquefy and therefore be of a smaller volume,    allowing the smaller volume of said liquefied gas to increase the volume available for said liquid and therefore draw a greater volume of said liquid into said accumulator, and    increasing the temperature of said liquefied gas to a second temperature to evaporate said gas, increase its pressure, and thereby pressurize said liquid.    
   
   
       9 . The method of  claim 8  further comprising said first temperature is the temperature near the bottom of an ocean.  
   
   
       10 . The method of  claim 8 , further comprising using electricity to increase the temperature of said pressurized gas.  
   
   
       11 . The method of  claim 10 , further comprising using the umbilical power cable of a subsea blowout preventer stack to provide the electric power to increase the temperature of said gas.  
   
   
       12 . The method of compensating for the loss of gas pressure in an accumulator due to the reduction of the temperature of the gas, comprising 
 providing a first chamber for the storage of pressurized liquids,    providing a second chamber for the storage of said pressurized gas,    increasing the temperature of said pressurized gas to increase the pressure of said gas and therefore to increase the pressure of said pressurized liquid.    
   
   
       13 . The method of  claim 12 , further comprising using electricity to increase the temperature of said pressurized gas.  
   
   
       14 . The method of  claim 13 , further comprising using the umbilical power cable of a subsea blowout preventer stack to provide the electric power to increase the temperature of said gas.  
   
   
       15 . The method of  claim 12 , further comprising that the method for increasing the temperature of said pressurized gas is by using heating elements within said second chamber.  
   
   
       16 . The method of  claim 12 , further comprising that the method for increasing the temperature of said pressurized gas is by using heating elements outside of said second chamber.  
   
   
       17 . The method of providing an accumulator for the storage of pressurized liquids by the use of a pressurized gas, comprising 
 providing for the storage of said pressurized gas in a first chamber,    providing for the storage of said pressurized liquids which are pressurized by said pressurized gas,    reducing the temperature of said gas at the surface to the anticipated temperature of the deepwater environment,    setting the pressure of the gas at the surface to the desired subsea pressure,    lowering the accumulators to the subsea environment, and    allowing the accumulators to become the same temperature as the subsea environment.    
   
   
       18 . The method of  claim 17 , further comprising that the reducing of the temperature of said gas at the surface is accomplished by using cooling coils within said first chamber.  
   
   
       19 . The method of  claim 17 , further comprising that the reducing of the temperature of said gas at the surface is accomplished by using cooling coils external to said first chamber.