Application of a dual tubing CO2 injection-water production system using a horizontal well for improving CO2 storage capacity: A case study in Pohang basin, offshore South Korea

초록

Carbon capture and storage (CCS) is an important technology for mitigating global warming and climate change through the permanent storage of CO2 in saline aquifer or depleted oil and gas reservoirs. Pressure build-up, which reduces CO2 storage capacity (CSC) in saline aquifers, is one of the most serious problems during the CO2 injection. Water production is an efficient way to relieve pressure build-up and thus improve CSC. The use of additional offshore platforms, production wells, pipelines, and pumps required for water production, however, increases the capital expenditure (CAPEX) of the project. Therefore, it is necessary to develop a CO2 injection method that can both improve CSC and reduce CAPEX. This study proposes a dual-tubing CO2 injection-water production horizontal well completion pattern for improving CSC, in which CO2 is injected at the heel while water is produced at the toe of the horizontal well. Four cases of well pattern were generated and simulated including (1) a single vertical CO2 injection well pattern, (2) a single horizontal CO2 injection well pattern, (3) a typical CO2 injection with water production pattern, and (4) a dual-tubing CO2 injection-water production horizontal well pattern. The CSC and the CAPEX of the proposed well pattern was then compared to those of the other cases in a saline aquifer in Pohang basin, offshore South Korea. Comparing the single well patterns (vertical and horizontal well), a vertical well for CO2 injection is the more effective than a horizontal well considering the CSC and CAPEX. The CCSPerformance (CSC/CAPEX) of a dual-tubing CO2 injection-water production horizontal well pattern is larger than that of a typical CO2 injection with water production pattern at the all CO2 injection/water production rates. The proposed a dual-tubing CO2 injection-water production horizontal well pattern was recommended because the CSC has been improved by 98.2% compared with a single vertical CO2 injection well pattern and the CAPEX was reduced by 37.1% compared with a typical CO2 injection with water production pattern. © 2018 GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies. All rights reserved.

키워드