SciTech Connect

Title: Management of water extracted from carbon sequestration projects

Management of water extracted from carbon sequestration projects Throughout the past decade, frequent discussions and debates have centered on the geological sequestration of carbon dioxide (CO{sub 2}). For sequestration to have a reasonably positive impact on atmospheric carbon levels, the anticipated volume of CO{sub 2} that would need to be injected is very large (many millions of tons per year). Many stakeholders have expressed concern about elevated formation pressure following the extended injection of CO{sub 2}. The injected CO{sub 2} plume could potentially extend for many kilometers from the injection well. If not properly managed and monitored, the increased formation pressure could stimulate new fractures or enlarge existing natural cracks or faults, so the CO{sub 2} or the brine pushed ahead of the plume could migrate vertically. One possible tool for management of formation pressure would be to extract water already residing in the formation where CO{sub 2} is being stored. The concept is that by removing water from the receiving formations (referred to as 'extracted water' to distinguish it from 'oil and gas produced water'), the pressure gradients caused by injection could be reduced, and additional pore space could be freed up to sequester CO{sub 2}. Such water extraction would occur away from the CO{sub 2} plume more » to avoid extracting a portion of the sequestered CO{sub 2} along with the formation water. While water extraction would not be a mandatory component of large-scale carbon storage programs, it could provide many benefits, such as reduction of pressure, increased space for CO{sub 2} storage, and potentially, 'plume steering.' Argonne National Laboratory is developing information for the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) to evaluate management of extracted water. If water is extracted from geological formations designated to receive injected CO{sub 2} for sequestration, the project operator will need to identify methods for managing very large volumes of water most of which will contain large quantities of salt and other dissolved minerals. Produced water from oil and gas production also typically contains large quantities of dissolved solids. Therefore, many of the same practices that are established and used for managing produced water also may be applicable for extracted water. This report describes the probable composition of the extracted water that is removed from the formations, options for managing the extracted water, the pros and cons of those options, and some opportunities for beneficial use of the water. Following the introductory material in Chapter 1, the report is divided into chapters covering the following topics: (Chapter 2) examines the formations that are likely candidates for CO{sub 2} sequestration and provides a general evaluation of the geochemical characteristics of the formations; (Chapter 3) makes some preliminary estimates of the volume of water that could be extracted; (Chapter 4) provides a qualitative review of many potential technologies and practices for managing extracted water and for each technology or management practice, pros and cons are provided; (Chapter 5) explores the potential costs of water management; and (Chapter 6) presents the conclusions. « less
Authors: ;
Publication Date:
OSTI Identifier:1009368
Report Number(s):ANL/EVS/R-11/1
TRN: US201107%%652
DOE Contract Number:DE-AC02-06CH11357
Resource Type:Technical Report
Research Org:Argonne National Laboratory (ANL)
Sponsoring Org:FE
Country of Publication:United States