Pre-injection Brine Production for Managing Pressure in Compartmentalized CO2 Storage Reservoirs

Abstract

We present a reservoir management approach for geologic CO 2 storage that combines CO 2 injection with brine extraction. In our approach, dual-mode wells are initially used to extract formation brine and subsequently used to inject CO 2 . These wells can also be used to monitor the subsurface during pre-injection brine extraction so that key data is acquired and analyzed prior to CO 2 injection. The relationship between pressure drawdown during pre-injection brine extraction and pressure buildup during CO 2 injection directly informs reservoir managers about CO 2 storage capacity. These data facilitate proactive reservoir management, and thus reduce costs and risks. The brine may be used directly as make-up brine for nearby reservoir operations; it can also be desalinated and/or treated for a variety of beneficial uses.

Optimal well placement and brine extraction for pressure management during CO2 sequestration

“…If this is the case, extraction well placement may have to be done at the beginning of the project based on the available data. Without drilling an additional well, pre-injection brine extraction may be conducted from the same injection well or another existing well, as recently suggested by Buscheck et al (2014). If an existing well is used, the optimization problem simplifies to only estimation of well operation parameters, not well location.…”

Review of CO2 storage efficiency in deep saline aquifers

“…Optimization of well placement and brine extraction, and use of multiple 5-spot well patterns for CO 2 injection and water production are discussed by Cihan et al (2014) and WesselBerg et al (2014), respectively. While the references quoted so far present cases of water production simultaneous with CO 2 injection, Buscheck et al (2014) present a storage management approach in which dual-mode wells are used first for water extraction and subsequently for CO 2 injection. Generally, as pointed out by Gorecki et al (2015), water extraction is the biggest single factor that increases storage capacity, hence storage efficiency, particularly for closed systems, while maintaining pressure below allowed limits.…”

Numerical simulation and optimization of CO2-enhanced water recovery by employing a genetic algorithm

“…Li et al (2014) established a three-dimensional injectioneextraction model to analyze the sensitivity of various parameters and considered the optimization of CO 2 storage capacity and saline water production under withdrawal conditions. Buscheck et al (2014) presented a dual-mode wells model where the wells are initially used to extract formation brine and are subsequently used to inject CO 2 to optimize the efficiency and economy of CO 2 -EWR. However, to date little attention has been paid to the water production efficiency of CO 2 -EWR and it has not been addressed how to optimize the CO 2 injection in order to achieve the maximum efficiency of water production as well as maximum possible CO 2 storage capacity while ensuring the reservoir safety.…”