Optimization of Scale Inhibitor Yields Longer Squeeze Life at Lower Concentration San Andres Horizontals
Coastal Chemical collaborated with operators in the San Andres horizontal play in West Texas to further optimize an established calcium sulfate scale inhibition program. Through laboratory testing using formation drill cuttings, core samples, and produced water chemistry representative of field conditions, Coastal Chemical developed the SI-2320T scale inhibitor. The new formulation demonstrated longer squeeze life at lower treatment concentrations compared to the previously used chemistry, while also incorporating a proprietary tracer technology to enable accurate monitoring of inhibitor residuals. Implementation of the optimized scale control program is estimated to reduce overall treatment costs by approximately 67% while maintaining effective scale prevention and improving operational efficiency.
CHALLENGES
- West Texas – San Andres Horizontal Wells
- Severe calcium sulfate deposition in production tubing, ESP pump, and lateral.
- Optimization of an already successful and proven scale inhibitor product.
SOLUTION
- Improvement of previously successful scale inhibitor development for prolonged control of calcium sulfate scale.
- Scale inhibitor frac application and squeeze program with Coastal Chemical’s SI-2320T tagged scale inhibitor. Total annual savings estimated at USD 1.99 million.
RESULTS
- Optimization of scale inhibitor for frac and squeeze application delivers extended protection at lower concentration.
- Scale inhibitor minimum effective concentration 40% reduction.
- Scale inhibitor adsorption to formation rock improved by 20%.
- Scale inhibitor desorption enhancement of 92%.
CALCIUM SULFATE SCALE REMEDIATION
West Texas San Andres Horizontal Calcium Sulfate Scale Control Optimization
Coastal Chemical worked with operators in the San Andres horizontal play in West Texas to proactively make improvement to the already successful scale inhibition program. Coastal Chemical’s goal was to optimize the scale inhibition program through extensive testing and evaluations of scale inhibitor chemistries.
The scale inhibitor testing and evaluation process was conducted through collaboration with operators in the area. Drill cutting and core samples were provided from the San Andres formation. The cutting and core samples, coupled with the extensive knowledge of the produced water chemistry, provided the most ideal testing and evaluation conditions to replicate that of the wells.
Coastal Chemical’s SI-2320T was developed as a result of the testing and evaluation process. SI-2320T provided longer scale inhibition life at lower concentration to that of Coastal Chemical’s SI-500T, which already has a proven success history for the San Andres horizontal play.
The SI-2320T tagged scale inhibitor also has a proprietary tag built into the chemistry. The tag allows for scale inhibitor residuals to be distinguished from the frac and/or squeeze treatment to that of continuous treatments. This distinction allows for accurate proactive monitoring and resulting re-squeeze treatments to prevent costly well interventions and cleanouts.
The calcium sulfate scale control program is estimated to have an overall cost reduction of 67% with the implementation of SI-2320T. The cost reduction is credited to the longer scale inhibition life at lower concentrations.
This case history is presented for illustration purposes only as results may vary between applications.