Method of attenuating annular pressure buildup using compressible particles

A method of placing compressible particles within a wellbore, comprising:

• running a first string of casing into a wellbore, the first string of casing extending into a subsurface to a first depth;
• running a second string of casing into the wellbore, the second string of casing extending into the subsurface to a depth that is greater than the first depth, and wherein the first string of casing surrounds an upper portion of the second string of casing forming an annular region;
• pumping a fluid mixture into the annular region, forming a fluid column, wherein the fluid mixture comprises:
• a carrier fluid;
• and
• a plurality of compressible particles dispersed in the carrier fluid;
• at least partially sealing the annular region along at least one depth above the first depth, wherein at least partially sealing the annular region along at least one depth comprises securing at least one sealing joint in series along the second string of casing, wherein each of the at least one sealing joint comprises cups that are concave;
• placing a column of cement around the second string of casing below the first depth;
• and
• placing a wellhead over the wellbore, thereby forming a trapped annulus in the wellbore over the annular region, wherein at least some of the compressible particles have a density that is less than a density of the carrier fluid such that the compressible particles are biased to rise in the trapped annulus;
• and wherein:
• the compressible particles comprises a plurality of carbonaceous particles, and
• the carbonaceous particles are designed to absorb pressure in response to thermal expansion of wellbore fluids within the annular region during a production of hydrocarbon fluids from the wellbore.

A wellbore having a trapped annulus, comprising:

• a first string of casing extending into a subsurface to a first depth;
• a second string of casing extending into the subsurface to a depth that is greater than the first depth, and wherein the first string of casing surrounds an upper portion of the second string of casing forming an annular region;
• a column of cement residing around the second string of casing below the first depth;
• a wellhead placed over the wellbore, forming a trapped annulus in the wellbore over the annular region;
• at least one barrier mechanism placed in series along the second string of casing to at least partially seal the annular region along the column of cement, wherein the at least one barrier mechanism comprises a plurality of cups spaced apart along the second string of casing, wherein the cups are concave;
• a fluid mixture residing within the trapped annulus comprising:
• a carrier fluid;
• and
• a plurality of compressible, carbonaceous particles dispersed in the carrier fluid, wherein the carbonaceous particles are designed to absorb pressure in response to thermal expansion of wellbore fluids within the annular region during a production of hydrocarbon fluids from the wellbore, wherein at least some of the compressible particles have a density that is less than a density of the carrier fluid such that the compressible particles are biased to rise in the trapped annulus.