Undesirable leakage to overlying formations with horizontal and vertical injection wells
Abstract
Deep saline aquifers are considered for underground storage of carbon dioxide. Undesirable leakage of injected CO2 to adjacent layers would disturb the storage process and can pollute shallower fresh water resources as well as atmosphere. Leaky caprocks, faults, and abandoned wells are examples of leaky pathways. In addition, the overpressure can reactivate a sealing fault or damage the caprock layer. Pressure management is applicable during the storage operation to avoid these consequences and to reduce undesirable leakage.The fluids can be injected through horizontal wells with a wider interval than vertical wells. Horizontal well injection would make less overpressure by delocalizing induced pressure especially in thin formations. In this work, numerical and analytical approaches are applied to model different leaky pathways with horizontal and vertical injection wells. we compare leakage rate and overpressure for horizontal and vertical injection wells in different leaky pathway systems. Results show that the horizontal well technology would allow high injection rates with lower leakage rate for leaky well, leaky fault, and leaky caprock cases. The overpressure would reduce considerably by horizontal well comparing to vertical well injection especially in leaky fault system. The horizontal well injection is an effective method to avoid reaching to threshold pressure of fault reactivation and prevent the consequent induced seismicity.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.H41B1440M
- Keywords:
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- 1847 Modeling;
- HYDROLOGY;
- 1849 Numerical approximations and analysis;
- HYDROLOGY;
- 5104 Fracture and flow;
- PHYSICAL PROPERTIES OF ROCKS;
- 5139 Transport properties;
- PHYSICAL PROPERTIES OF ROCKS