Characteristics and performance of a deep-ocean disposal system for low-purity CO2 gas via gas lift effect

T. Saito et al., Characteristics and performance of a deep-ocean disposal system for low-purity CO2 gas via gas lift effect, ENERG FUEL, 15(2), 2001, pp. 285-292
Citations number
Categorie Soggetti
Environmental Engineering & Energy
Journal title
ISSN journal
0887-0624 → ACNP
Year of publication
285 - 292
SICI code
Ocean sequestration of CO2 is a hopeful option to solve the global warming problems. We proposed the Gas Lift Advanced Dissolution (GLAD) System for e fficient sequestration of pure CO2 at deep sea. The GLAD system is an inver se-J pipeline set in the ocean between 200 and 3000 m in depth. We have rec ently improved it to treat low-purity CO2 gas to reduce the cost for separa tion and capture of CO2 from exhausted gas. The newly developed system, nam ed the Progressive Gas Lift Advanced Dissolution (P-GLAD) System, is to dis solve low-purity CO2 bubbles into seawater at a depth of 200-300 m and at t he same time sequestrate CO2 at the deep sea of 1000-3000 m. Previous ideas of deep-sea sequestration of CO2, including storage of liquid CO2 on the d eep-sea floor and direct releasing of liquid CO2 into the deep sea, necessi tate the consumption of a huge amount of energy, because the realization of these ideas requires both high-purity capture of CO2 from exhausted gas an d liquefaction of the CO2. To realize deep-sea sequestration of CO2 with lo w energy consumption and low environmental impact, we utilize a gas-lift ef fect to simultaneously dissolve low-purity CO2 gas into shallow seawater an d transport the CO2 solution to a great depth. The present paper describes basic characteristics and performance of the P-GLAD system for low-purity C O2 gases, experimentally and numerically. It is demonstrated that the syste m has satisfactory ability to both dissolve CO2 gas and pump the CO2 soluti on. To confirm economic feasibility of the P-GLAD System, we also discuss t he overall cost estimation including an additional system for CO2 capturing as well as the construction of P-GLAD. The cost for the P-GLAD is estimate d to be half of those for previous ideas.