|
Title:
|
|
Cost evaluation of CO2 sequestration by aqueous mineral carbonation
|
|
|
|
Author(s):
|
|
|
|
|
|
Published by:
|
Publication date:
|
|
ECN
Biomass, Coal and Environmental Research
|
7-5-2007
|
|
|
|
ECN report number:
|
Document type:
|
|
ECN-W--07-014
|
Article (scientific)
|
|
|
|
Number of pages:
|
|
|
13
|
|
Published in: Energy Conversion and Management (Elsevier), , 2007, Vol.48, p.1923-1935.
Abstract:
A cost evaluation of CO2 sequestration by aqueous mineral carbonation has been made using either wollastonite (CaSiO3) or steel
slag as feedstock. First, the process was simulated to determine the properties of the streams as well as the power and heat consumption
of the process equipment. Second, a basic design was made for the major process equipment, and total investment costs were estimated
with the help of the publicly available literature and a factorial cost estimation method. Finally, the sequestration costs were determined
on the basis of the depreciation of investments and variable and fixed operating costs. Estimated costs are 102 and 77 €/ton CO2 net
avoided for wollastonite and steel slag, respectively. For wollastonite, the major costs are associated with the feedstock and the electricity
consumption for grinding and compression (54 and 26 €/ton CO2 avoided, respectively). A sensitivity analysis showed that additional
influential parameters in the sequestration costs include the liquid-to-solid ratio in the carbonation reactor and the possible value of
the carbonated product. The sequestration costs for steel slag are significantly lower due to the absence of costs for the feedstock.
Although various options for potential cost reduction have been identified, CO2 sequestration by current aqueous carbonation processes
seems expensive relative to other CO2 storage technologies. The permanent and inherently safe sequestration of CO2 by mineral carbonation
may justify higher costs, but further cost reductions are required, particularly in view of (current) prices of CO2 emission rights.
Niche applications of mineral carbonation with a solid residue such as steel slag as feedstock and/or a useful carbonated product hold the
best prospects for an economically feasible CO2 sequestration process.
Back to List