The Importance of Water Characterization for CCUS

The storage capacity of CO2 in water is influenced by various factors, including reservoir pressure, temperature, salinity of formation water and the structural characteristics of the trap.

Typically, during the project evaluation phase, exploration wells are drilled through the stack of water-filled reservoirs. Each layer is a potential candidate for CO2 injection and requires thorough evaluation.

Salinity and ion composition plays a significant role in determining how much CO2 can be dissolved in water. The most efficient way of assessing water properties across multiple intervals is by using Wireline Formation Testers (WFT) in the open hole. Latest generation of these tools is measuring density, resistivity and pH of water in reservoir conditions. These measurements help quantify the salinity of formation water.

This information can be used to optimize formation evaluation program in real time, including sample capturing and subsequent downhole testing.