Abstract
A two-component lost circulation material (LCM) system is developed to mitigate seepage to moderate type loss of circulation using materials and polymers having different physical and chemical properties. The first component or component I is a slurry containing a carrier fluid such as water, a particulate or filler material such as fly ash, a fibrous material such as polypropylene fibers, and a water absorbing acrylic polymer. The second component or component II is a solution of sodium hydroxide in water. Component II is used as activator and when in contact with component I, the sodium hydroxide triggers the polyacrylic polymers in component I to absorb water in the slurry. As a result the whole system is swollen up and a generation of thick mass of the system achieved. This approach is used to address the lost circulation scenarios while drilling through fractured and cavernous zones. A comprehensive lab testing of the two component lost circulation material system has been carried out using pore plugging test (PPT) apparatus to prove its efficiency to seal off the fractures of width up to 2 mm. The results of PPT experiments show that the two component lost circulation material system is capable of controlling loss of circulation into fractures of width up to 2 mm under high pressure (1500 psi) and high temperature (250 °F) conditions. The new two component lost circulation system will provide a reliable solution to address seepage to moderate type loss of circulation.
