Ocean Applications for Carbon Dioxide Sequestration

Abstract

Increase in the concentration of carbon dioxide (CO 2 ) in the atmosphere is being attributed to the adverse effects such as warming of the planet; increase in the sea level; variation in the atmospheric and ocean circulation patterns; snow cover variation; and, sea ice extent. One of the common approaches followed in the mitigation efforts is the study on the reduction of the emissions of CO 2 from the major point sources such as coal fired power plants, steel plants, cement industries. Direct injection of the carbon dioxide into the deep oceans, mineral carbonation applications, in situ replacement of the gas hydrate into the carbon dioxide hydrates, micro algal sequestration and iron fertilization are some of the ocean sequestration options studied in the literature. Present chapter studies the feasibility of different ocean sequestration methods in comparison with the technological requirements for the realization of these methods.The relative merits of the methods, the technological challenges, ecological and environmental issues needing detailed studies for the application are discussed in this chapter. The experiments conducted on the mineral carbonation of industrial wastes such as steel slag using direct and indirect methods are discussed, considering the Linz-Donawitz converter slag. The carbonation efficiency for different conditions is compared and the structure of the resulting materials is analyzed. The prospective applications for coastal protective measures and artificial reef growth and the state of the art in similar applications using the concrete structure are discussed. The chapter discusses in detail the energy requirements in mineral carbonation methodology using the steel slag.