System and Apparatus for Creating a Liquid Carbon Dioxide Fracturing Fluid
AssigneePraxair Technology, Inc.
InventorsRichard M. Kelly, Nick Joseph Degenstein, Bernard Thomas Neu
Life of this patent
Estimating the term…
Abstract
A method, system, and apparatus required for creating a mixture of dry proppant and liquid carbon dioxide (LCO2) for fracturing oil and gas formations is presented. The operation includes making a mixture of dry proppant and liquid carbon dioxide (LCO2) for use in a fracturing operation by supplying dry proppant that is pressurized to between 75 and 600 psia with a gas; further supplying a stream of sub-cooled LCO2 having a pressure substantially equal to that of the pressurized dry proppant; and adding dry, pressurized proppant to the stream of sub-cooled LCO2, thereby forming a mixed LCO2 and proppant fracturing slurry.
Claims30
A system for making a fracturing fluid comprising a mixture of dry proppant and liquid carbon dioxide (LCO2) for use in a fracturing operation, comprising:
- loading dry proppant into at least one dry proppant storage vessel with one or more conveying means;
- pressurizing said proppant storage vessel(s) to between 75 and 600 psia with a gas, thereby pressurizing said proppant storage vessel(s) and ensuring said proppant remains dry;
- supplying a stream of sub-cooled LCO2 having a pressure substantially equal to the pressurized proppant storage vessel(s);
- and
- adding dry proppant from the pressurized proppant storage vessel(s) to the stream of sub-cooled LCO2, thereby forming a mixed LCO2 and proppant fracturing fluid.
An apparatus employed in a fracturing operation, comprising:
- at least one pressurized proppant storage vessel containing proppant and a gas, said vessel connected to a metering device for adding proppant into a sub-cooled LCO2 stream and;
- a sub-cooler for ensuring that the liquid carbon dioxide (LCO2) is in a sub-cooled liquid state and/or a booster pump(s) for increasing the pressure of the LCO2 stream above its saturation point and conveying the LCO2 to a mixing point, wherein proppant is metered into the LCO2 to form a fracturing fluid.
A method for controlling a fracturing fluid composition, wherein a dry proppant is being routed and introduced into LCO2, thereby forming a liquid carbon dioxide proppant fracturing fluid.
A system for combining metered dry and warm proppant with a sub-cooled LCO2 stream resulting in a fracturing fluid comprising:
- (i) mixing of said proppant and LCO2 preventing carbon dioxide vapor from being generated by providing a pressure level of 50 psi NPSH or at least a pressure sufficiently above saturation conditions;
- and
- (ii) recondensing any gaseous carbon dioxide entrained within the proppant of said fracturing fluid.
A system for making a fracturing fluid comprising a mixture of dry proppant and liquid carbon dioxide (LCO2) for use in a fracturing operation, comprising:
- supplying dry proppant that is pressurized to between 75 and 600 psia with a gas;
- providing a stream of sub-cooled LCO2 having a pressure substantially equal to the pressurized dry proppant;
- and
- adding dry, pressurized proppant to the stream of sub-cooled LCO2, thereby forming a mixed LCO2 and proppant fracturing fluid.
Dependencies are inferred from the claim text.