Optimizing Cementing Design for Extreme Conditions: High-Permeability, Depleted Steam Flood Reservoirs with Economic Constraints

Abstract A new cementing guideline in depleted steam formation is proposed in this paper. It covers cementing placement technique and cement composition adjustment for both improve bonding and squeeze interval. The design is based on the current condition of reservoir behaviour as the steam phase changes. The results are compared to the previous guideline used in the same field X regarding to bonding quality proven by CBL result and times of cementing conducted in a same well. This method focuses on slurry placement by positioning the slurry a few feet above the shale break or casing shoe. To enhance its effectiveness, the slurry rheology is modified by reducing fluid loss control, thereby minimizing slurry losses into the formation. Furthermore, the slurry pumping technique is redesigned through a combination of the bullheading and equalization methods, marking a difference from previous approaches that relied solely on bullheading. Nowadays, this technique has been applied in several wells in field X to improve cement bonding. The results were encouraging with successful ratio is up to 83% where the wells are completed with one-time cementing job and show improve quality of cement bonding. Additionally, this technique was also given positive result for squeeze formation. It is quite interesting, where 80% of trial were successfully completed with one-time cementing job with good cement quality as indicated by the hold pressure test. Nevertheless, the previous method of cementing for improve bonding and squeeze zone operations required 2–4 repetitions, consuming a total of 600–900 sacks of cement. This approach led to high material usage and extended operation time. A new cementing method was implemented, allowing the operation to be successfully completed in a single attempt with only 200–300 sacks of cement. This new approach not only significantly reduced cement consumption but also shortened rig operation time by 12–36 hours, resulting in a substantial reduction in overall operational costs of approximately 15,000 USD/cementing job. The novelty of this paper is a proven technique of adjustment in slurry composition and new placement technique in a depleted steam formation.