Carbon Dioxide Ocean Disposal
In 1990, PICHTR and the Hawaii Natural Energy Institute of the University of Hawaii engaged in research on extracting CO2 from combustion gases and sequestering it in the deep ocean. The program dealt with technical and economic analyses of CO2 separation from fossil fuel combustions. This program was expanded to include experimental and theoretical investigations of deep ocean CO2 disposal which as produced dozens of publications, as well as a unique High-Pressure CO2 Mixing Facility capable of reproducing the dynamics of the CO2 injection process in the deep ocean.
Work on oceanic sequestration included field tests addressing uncertainties related to the effectiveness of ocean disposal as a means of long-term disposal, and concerns related to impacts on the marine ecosystem. The field test phase included: (1) a pilot test releasing small amounts of CO2 into an open ocean site for about one month; (2) a long-term-at least one year – test to assess acute and chronic biological impacts of the marine ecosystem; and (3) a final pilot scale test involving the disposal of CO2 captured from a commercial power plant over a period of several years.
The site for these tests was the Natural Energy Laboratory of Hawaii Authority (NELHA) facility. This facility has near shore access to deep waters, as well as several unused submerged pipelines that could assist in discharging CO2.