A 1000 MWth boiler for chemical-looping combustion of solid fuels – Discussion of design and costs

Abstract

h i g h l i g h t sChemical-Looping Combustion (CLC) is a novel combustion technology for CO 2 capture. CLC avoids large costs and energy penalties of gas separation for CO 2 capture. A scale-up of CLC technology for solid fuels to 1000 MW th is investigated. CLC technology is similar to CFB technology. Estimated cost of CLC with capture relative to CFB without capture is 20 €/tonne CO 2 . a b s t r a c tMore than 2000 h of solid-fuel CLC operation in a number of smaller pilot units clearly indicate that the concept works. A scale-up of the technology to 1000 MW th is investigated in terms of mass and heat balances, flows, solids inventories, boiler dimensions and the major differences between a full-scale Circulating Fluidized-Bed (CFB) boiler and a Chemical-Looping Combustion CFB (CLC-CFB). Furthermore, the additional cost of CLC-CFB relative to CFB technology is analysed and found to be 20 €/tonne CO 2 . The largest cost is made up of compression of CO 2 , which is common to all capture technologies. Although the need for oxygen to manage incomplete conversion is estimated to be only a tenth of that of oxy-fuel combustion, oxygen production is nonetheless the second largest cost. Other significant costs include oxygen-carrier material, increased boiler cost and steam for fluidization of the fuel reactor.

Chemical Looping Combustion: an Emerging Carbon Capture Technology

“…The selected system of oxygen carriers shown in table 1 is designed to yield a perovskite structure, in this case with Ca and Mn as constituting elements (ABO 3-␦ , with AϭCa, BϭMn). Such perovskite structures are known to show good performance for chemical looping combustion [2]. The increase in sintering temperature and sintering time can be used to increase the mechanical strength of oxygen carrier materials.…”

“…The design for 1GW th is being considered [2]. In the heart of CL technology is the oxygen carrier, which is indispensable for transferring the oxygen to the fuel.…”

“…In the EC-7FP project SUCCESS, MWatt-scale Chemical looping with up-scaled fabrication of selected materials will be investigated. This paper reports on the influence of the different steps in the manufacturing process on the CLC performance of oxygen carriers for a selection of calcium manganate materials with perovskite crystal structure [2].…”

Emerging CO2 capture systems

“…9 and 10, may give the impression that the technology would differ significantly from the power plants using circulating fluidized-bed (CFB) technology. However, a proposed design of a 1000 MW th CLC power plant (Lyngfelt and Leckner, 2015) rather underlines the similarities, Fig. 11.…”

Microstructural Stability of Tailored CaMn0.875−xFexTi0.125O3−δ Perovskite Oxygen Carrier Materials for Chemical Looping Combustion

“…Chemical looping combustion (CLC) shows great potential as a technology with high efficiency and low cost for carbon capture . The cost of CO 2 capture is estimated to be as low as € 16–26 per metric ton with an energy penalty of 4 % for coal combustion . Unlike other precombustion and postcombustion techniques, it allows the inherent separation of CO 2 during fuel combustion.…”