Title

A Novel Approach to Carbon Dioxide Capture and Storage

Author

Brett P. Spigarelli, Michigan Technological University

Date of Award

2013

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Chemical Engineering (PhD)

College, School or Department Name

Department of Chemical Engineering

Advisor

Komar S Kawatra

Abstract

The novel approach to carbon capture and storage (CCS) described in this dissertation is a significant departure from the conventional approach to CCS. The novel approach uses a sodium carbonate solution to first capture CO₂ from post combustion flue gas streams. The captured CO₂ is then reacted with an alkaline industrial waste material, at ambient conditions, to regenerate the carbonate solution and permanently store the CO₂ in the form of an added value carbonate mineral. Conventional CCS makes use of a hazardous amine solution for CO₂ capture, a costly thermal regeneration stage, and the underground storage of supercritical CO₂. The objective of the present dissertation was to examine each individual stage (capture and storage) of the proposed approach to CCS.

Study of the capture stage found that a 2% w/w sodium carbonate solution was optimal for CO₂ absorption in the present system. The 2% solution yielded the best tradeoff between the CO₂ absorption rate and the CO₂ absorption capacity of the solutions tested. Examination of CO₂ absorption in the presence of flue gas impurities (NO_x and SO_x) found that carbonate solutions possess a significant advantage over amine solutions, that they could be used for multi-pollutant capture. All the NO_x and SO_x fed to the carbonate solution was able to be captured. Optimization studies found that it was possible to increase the absorption rate of CO₂ into the carbonate solution by adding a surfactant to the solution to chemically alter the gas bubble size. The absorption rate of CO₂ was increased by as much as 14%.

Three coal combustion fly ash materials were chosen as the alkaline industrial waste materials to study the storage CO₂ and regeneration the absorbent. X-ray diffraction analysis on reacted fly ash samples confirmed that the captured CO₂ reacts with the fly ash materials to form a carbonate mineral, specifically calcite. Studies found that after a five day reaction time, 75% utilization of the waste material for CO₂ storage could be achieved, while regenerating the absorbent. The regenerated absorbent exhibited a nearly identical CO₂ absorption capacity and CO₂ absorption rate as a fresh Na₂CO₃ solution.

Recommended Citation

Spigarelli, Brett P., "A Novel Approach to Carbon Dioxide Capture and Storage", Dissertation, Michigan Technological University, 2013.

https://doi.org/10.37099/mtu.dc.etds/633