Ex-situ and in-situ mineral carbonation as a means to sequester carbon dioxide

Conference · Thu Jan 01 04:00:00 EST 2004

OSTI ID:895240

Gerdemann, Stephen J; Dahlin, David C; O'Connor, William K; Penner, Larry R; Rush, G E

The U. S. Department of Energy's Albany Research Center is investigating mineral carbonation as a method of sequestering CO2 from coal-fired-power plants. Magnesium-silicate minerals such as serpentine [Mg3Si2O5(OH)4] and olivine (Mg2SiO4) react with CO2 to produce magnesite (MgCO3), and the calcium-silicate mineral, wollastonite (CaSiO3), reacts to form calcite (CaCO3). It is possible to carry out these reactions either ex situ (above ground in a traditional chemical processing plant) or in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals). For ex situ mineral carbonation to be economically attractive, the reaction must proceed quickly to near completion. The reaction rate is accelerated by raising the activity of CO2 in solution, heat (but not too much), reducing the particle size, high-intensity grinding to disrupt the crystal structure, and, in the case of serpentine, heat-treatment to remove the chemically bound water. All of these carry energy/economic penalties. An economic study illustrates the impact of mineral availability and process parameters on the cost of ex situ carbon sequestration. In situ carbonation offers economic advantages over ex situ processes, because no chemical plant is required. Knowledge gained from the ex situ work was applied to long-term experiments designed to simulate in situ CO2 storage conditions. The Columbia River Basalt Group (CRBG), a multi-layered basaltic lava formation, has potentially favorable mineralogy (up to 25% combined concentration of Ca, Fe2+, and Mg cations) for storage of CO2. However, more information about the interaction of CO2 with aquifers and the host rock is needed. Core samples from the CRBG, as well as samples of olivine, serpentine, and sandstone, were reacted in an autoclave for up to 2000 hours at elevated temperatures and pressures. Changes in core porosity, secondary mineralizations, and both solution and solid chemistry were measured.

• Research Organization: Albany Research Center (ARC), Albany, OR
• Sponsoring Organization: USDOE - Office of Fossil Energy (FE)
• OSTI ID: 895240
• Report Number(s): DOE/ARC-2004-031
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
20 FOSSIL-FUELED POWER PLANTS
36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
CARBON DIOXIDE
CARBON SEQUESTRATION
CHEMICAL PLANTS
CO2
COAL
COLUMBIA RIVER
CRYSTAL STRUCTURE
ECONOMICS
GRINDING
LAVA
MINERALOGY
OLIVINE
PARTICLE SIZE
PITTSBURGH
REACTION KINETICS
SERPENTINE
carbon dioxide
carbon sequestration
mineal carbonation