| Abstract |
Several challenges are encountered while geothermal well casings are cemented because of high temperature, presence of carbon dioxide, and lost circulation. To address lost circulation, one method is to pump the cement job in the reverse path down the annulus while taking returns through the casing or drill pipe. This reduces the bottom hole circulating pressure and the chance of formation breakdown, which minimizes the need for top out jobs. The presence of carbon dioxide in some of the wells can lead to corrosion, and well integrity can be comprised. To deal with this issue, a foamed latex cement blend was used for proper zonal isolation instead of the conventional Class G cement mix. The successful execution of this cementing process is based on proper cementing design, appropriate equipment for cement pumping, detailed planning of the job and flawless execution of the plan. |