Abstract
Abstract
One of the major drawbacks of using foam to reduce the gas mobility in oil fields is its stability at harsh reservoir conditions. A key factor that impacts the foam stability is the type and chemistry of the water used to prepare the treatment fluid. The objective of this work is to investigate the impact of treated produced water obtained from the Zero Liquid Discharge (ZLD) technology on foam stability and to promote environmental sustainability/water circularity in foam assisted gas injection projects.
In this study, a high-pressure high-temperature (HPHT) foam analyzer was used to investigate foam properties. High salinity brine (HSW) and treated produced water (TPW) from the ZLD technology were used to prepare the surfactant solutions. One foaming agent was used to conduct this assessment. Foam half-life, foam structure, and bubble counts were measured to assess foam stability. The results demonstrated that the TPW has a significant impact on foam stability. The foam generated using the TPW from the ZLD technology is more stable than that generated using the HSW. The foam generated using the TPW has a greater foam density (higher bubble count and smaller size) when compared to that produced using the HSW. In additions, the results showed that the foam generated using TPW has at least 24 times longer foam half-life than that produced using the HSW. Smaller bubble size, larger bubble count, and longer foam half-life are indicative of more stable and stronger foams.
This work, for the first time, evaluates the impact of TPW on foam stability. The promising results obtained suggest that the proposed method of using TPW for generating stable foams may overcome some of the challenges associated with conventional foam applications besides promoting environmental sustainability in foam assisted gas injection projects due to effective produced water recycle/reuse.