Publications

The worlds largest field on steam flood is host to many challenging workover opportunities. One in particular this paper will address is steam breakthrough in open-hole, gravel packed production wells. Steam from the injectors can inflow into the producers, sometimes very quickly via a high perm streak or ultimately as a function of a mature steam flood. This unwanted steam, if left unchecked can boost WOR, impairing production and increase well pressures making them difficult to kill thus restricting workover flexibility. Effectively isolating these zones within a gravel pack can prove to be very difficult.Successful remedial squeeze cementing requires the slurry to penetrate the narrow slots of the wirewrapped screens, gravel pack and desirably, some distance into the formation. Conventional squeeze cement slurries cannot accomplish this. The current accepted thinking, as a necessary condition for injection is that the slurry particle diameter must be 3 to 5 times smaller than the gap to be filled. In order to meet this condition, novel, improved micro-cement slurries have been developed which exhibit the required traits for isolating the steam such as: low viscosity, excellent fluid loss control, low permeability, high compressive strength and high shear bond strength.Extensive lab testing in addition to a full scale yard test with screens and 20/40 mesh gravel pack demonstrated the cement systems competence and enabled the field trial to commence. To date, over 40 wells suffering from steam breakthrough have been successfully remediated with the new micro-cement slurries establishing it as a viable workover technique.