Carbon capture and storage (CCS) is broadly recognised as having the potential to play a key role in meeting climate change targets, delivering low carbon heat and power, decarbonising industry and, more recently, its ability to facilitate the net removal of CO2 from the atmosphere. However, despite this broad consensus and its technical maturity, CCS has not yet been deployed on a scale commensurate with the ambitions articulated a decade ago. Thus, in this paper we review the current state-of-the-art of CO2 capture, transport, utilisation and storage from a multi-scale perspective, moving from the global to molecular scales. In light of the COP21 commitments to limit warming to less than 2 °C, we extend the remit of this study to include the key negative emissions technologies (NETs) of bioenergy with CCS (BECCS), and direct air capture (DAC). Cognisant of the non-technical barriers to deploying CCS, we reflect on recent experience from the UK's CCS commercialisation programme and consider the commercial and political barriers to the large-scale deployment of CCS. In all areas, we focus on identifying and clearly articulating the key research challenges that could usefully be addressed in the coming decade.

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Carbon capture and storage (CCS): the way forward

http://digital.csic.es/bitstream/10261/78793/1/Progress%20in%20chemical-looping%20combustion%20and%20ref....2012.pdf

Progress in chemical-looping combustion and reforming technologies

In recent years, Carbon Capture and Storage (Sequestration) (CCS) has been proposed as a potential method to allow the continued use of fossil-fuelled power stations whilst preventing emissions of CO2 from reaching the atmosphere. Gas, coal (and biomass)-fired power stations can respond to changes in demand more readily than many other sources of electricity production, hence the importance of retaining them as an option in the energy mix. Here, we review the leading CO2 capture technologies, available in the short and long term, and their technological maturity, before discussing CO2 transport and storage. Current pilot plants and demonstrations are highlighted, as is the importance of optimising the CCS system as a whole. Other topics briefly discussed include the viability of both the capture of CO2 from the air and CO2 reutilisation as climate change mitigation strategies. Finally, we discuss the economic and legal aspects of CCS.

Carbon capture and storage update

Rock, snow and ice masses are often dislodged on steep slopes of mountainous regions. The masses, which typically are in the form of innumerable discrete blocks or granules, initially accelerate down the slope until the angle of inclination of the bed approaches the horizontal and bed friction eventually brings them to rest. The present paper describes an initial investigation which considers the idealized problem of a finite mass of material released from rest on a rough inclined plane. The granular mass is treated as a frictional Coulomb-like continuum with a Coulomb-like basal friction law. Depth-averaged equations of motion are derived; they bear a superficial resemblance to the nonlinear shallow-water wave equations. Two similarity solutions are found for the motion. They both are of surprisingly simple analytical form and show a rather unanticipated behaviour. One has the form of a pile of granular material in the shape of a parabolic cap and the other has the form of an M-wave with vertical faces at the leading and trailing edges. The linear stability of the similarity solutions is studied. A restricted stability analysis, in which the spread is left unperturbed shows them to be stable, suggesting that mathematically both are possible asymptotic wave forms. Two numerical finite-difference schemes, one of Lagrangian, the other of Eulerian type, are presented. While the Eulerian technique is able to reproduce the M-wave similarity solution, it appears to give spurious results for more general initial conditions and the Lagrangian technique is best suited for the present problem. The numerical predictions are compared with laboratory experiments of Huber (1980) involving the motion of gravel released from rest on a rough inclined plane. Although in these experiments the continuum approximation breaks down at large times when the gravel layer is only a few particle diameters thick, the general features of the development of the gravel mass are well predicted by the numerical solutions.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112089000340

The motion of a finite mass of granular material down a rough incline

Entropy generation minimization (finite time thermodynamics, or thermodynamic optimization) is the method that combines into simple models the most basic concepts of heat transfer, fluid mechanics, and thermodynamics. These simple models are used in the optimization of real (irreversible) devices and processes, subject to finite‐size and finite‐time constraints. The review traces the development and adoption of the method in several sectors of mainstream thermal engineering and science: cryogenics, heat transfer, education, storage systems, solar power plants, nuclear and fossil power plants, and refrigerators. Emphasis is placed on the fundamental and technological importance of the optimization method and its results, the pedagogical merits of the method, and the chronological development of the field.

Entropy generation minimization: The new thermodynamics of finite-size devices and finite-time processes

Evaluation of a chemical-looping-combustion power-generation system by graphic exergy analysis

A new advanced power-generation system using chemical-looping combustion

A novel combustor without flame is proposed by employing chemical-looping reactions. Here we report the promising results on the novel combustor by kinetic and crystallographic study. We found that the NiO particles mixed with YSZ (yttria-stabilized zirconia) have very good properties for the oxygen carrier in the loop with respect to the reaction rate, conversion, and physical strength; especially the rate of oxidation of Ni is increased significantly. Furthermore, we observed that NOx was not generated in this combustor. Another significant feature, concerning the greenhouse impact, is that CO2 can easily be recovered.

A Novel Chemical-Looping Combustor without NOx Formation

A new kind of solid looping material, NiO/NiAl2O4, was synthesized based on integration of NiO, as solid reactant, with a composite metal oxide of NiAl2O4, as a binder, for applying it to chemical-looping combustion. The chemical looping combustion including reduction (fuel with metal) and oxidation (air with the reduced metal oxide) could make a breakthrough in simultaneous contribution to both energy and environmental issues. The reactivity of the reduction and oxidation was investigated by TGA (thermogravimetrical analysis). The results obtained here indicated that the new looping material, NiO/NiAl2O4, might significantly improve reaction rate, conversion, and regenerability in cyclic reaction, compared with the other materials. In addition, the carbon deposition can be completely avoided by addition of water vapor at a ratio of H2O/CH4 = 2.0. These results suggest that this new looping material of NiO/NiAl2O4 may play a vital role in developing chemical-looping combustion.

Development of a Novel Chemical-Looping Combustion: Synthesis of a Solid Looping Material of NiO/NiAl2O4

A novel combustor based on controlled chemical-looping reactions without flame differs from the traditional combustor, in which the fuel is in direct contact with air. It allows CO2 to be easily recovered and promises advanced-level thermal efficiency for power generation. Promising results of laboratory experiments with the novel combustor are presented here. We found that NiO particles mixed with YSZ (yttria-stabilized zirconia) have very good properties with respect to oxidation rate, conversion, and physical strength. Especially, the rate of oxidation of Ni particles is increased significantly. The effects of YSZ content in the particle, the reaction temperature, the particle size, and the water vapor concentration were examined by studying the kinetic behavior of reactions. These promising results revealed high potential for applying chemical-looping combustion in a power-generation plant.

Masaru Ishida

Papers

Evaluation of a chemical-looping-combustion power-generation system by graphic exergy analysis

A new advanced power-generation system using chemical-looping combustion

A Novel Chemical-Looping Combustor without NOx Formation

Development of a Novel Chemical-Looping Combustion: Synthesis of a Solid Looping Material of NiO/NiAl2O4

A Novel Combustor Based on Chemical-Looping Reactions and Its Reaction Kinetics