| Popis: |
This paper presents a new high temperature retarder that can effectively delay the setting time of an oil and gas cement up to 450 °F via a single polymer only instead of the usual combination of synthetic copolymer of 2-acrylamido-2-methylpropane sulfonic acid and acrylic acid (AMPS®/AA)-based or natural lignosulfonate-based polymer retarder along with an intensifier small organic molecules like tartaric, citric, or gluconic acids that are relatively costly and sometimes degrade the performance of cement fluid loss control polymer. More interestingly, this new differentiated polymer cement retarder provides unique synergistic property in presence of an AMPS®-based cement fluid loss control polymer that is giving additional suspension capability useful for water-extended lightweight density cement slurry; thereby, eliminating the need for an extra viscosifying agent and/or high temperature suspending aid. With the use of this new polymer retarder, complicated cement design is actually simplified having less additive in the mixture, giving the advantage of better logistics, easier operations, and cheaper economics. |
