Prospects in Waste Oil Shale Ash Sustainable Valorization

An innovative approach utilizing highly alkaline oil shale waste ash and carbon dioxide gas (CO2), associated with power production, as a resource for production of precipitated calcium carbonate (PCC) is introduced in this paper. The specifics and feasibility of the integrated ash valorization and CO2 sequestration process by indirect aqueous carbonation of lime-consisting ash were elaborated and the main parameters established. Detailed description of the formed precipitates was included. Complimentary carbonation experiments with commercial CaO fine powder were conducted for comparative characterization of the final products obtained on the basis of two different raw materials. Finally, the expected CO2 uptake was evaluated.

Authors:

• Olga Velts
• Mai Uibu
• Juha Kallas
• Rein Kuusik

Keywords:

• Calcium Carbonate
• Carbon Dioxide Sequestration
• Oil Shale Ash
• Waste Valorization.

References:

[1] Carbon Dioxide Information Analysis Center, Environmental Sciences
Division (US), "CO2 emissions - Estonia," March 2011,
http://data.worldbank.org/indicator/EN.ATM.CO2E.PC/countries/EE-
7E-XR
[2] L. Savitskaja, "Man-made changes of groundwater quality," in Geology
and Mineral Resources of Estonia, A. Raukas, A. Teedumäe, Eds.
Tallinn: Estonian Academy Publishers, 1997, pp. 152-156.
[3] M. Uibu, M. Uus, and R. Kuusik, "CO2 mineral sequestration in oilshale
wastes from Estonian power production," J. Environ. Manage.,
vol. 90, no. 2, pp. 1253-1260, 2009.
[4] R. Kuusik, M. Uus, M. Uibu, et al, "Method for neutralization of
alkaline waste water with carbon dioxide included in flue gas," Patent nr
EE05349B1
[5] O. Velts, M. Hautaniemi, J. Kallas, and R. Kuusik, "Modeling calcium
dissolution from oil shale ash: PART 1. Ca dissolution during ash
washing in a batch reactor," Fuel. Process. Tech., vol. 91, no. 5, pp.
486-490, 2010.
[6] O. Velts, M. Hautaniemi, J. Kallas, M. Kuosa, and R. Kuusik,
"Modeling calcium dissolution from oil shale ash: PART 2. Continuous
washing of the ash layer," Fuel. Process. Tech., vol. 91, no. 5, pp. 491-
495, 2010.
[7] O. Velts, M. Hautaniemi, M. Uibu, J. Kallas, and R. Kuusik, "Modelling
of CO2 mass transfer and hydrodynamics in a semi-batch reactor,"
Materials, Methods & Technologies, vol. 4, no. 2, pp. 68-79, 2010.
Available at: http://www.science-journals.eu/mmt/index.html
[8] Specialty Minerals Inc. (SMI), "What is PCC?" March 2011,
http://www.specialtyminerals.com/our-minerals/what-is-pcc/