Sorbent Cost and Performance in CO₂ Capture Systems

Abstract

Power plants are prime candidates to apply CO2 capture for final storage as a mitigation option for climate change. Many CO2 capture concepts make use of a sorption−desorption cycle to separate CO2 from flue gas or O2 from air. These include commercial absorption processes, as well as processes using new sorbent formulations, adsorption, and high-temperature chemical looping cycles for CO2 and O2. All of these new processes must confront the large scale of carbon flows typical in a power plant. In this work, a common mass balance for all of these processes is used to define a parameter that highlights the minimum sorbent performance required to keep sorbent makeup costs at an acceptable level. A well-established reference system for which reliable commercial data exist (absorption with monoethanolamine, MEA) is used as a technoeconomic baseline to show that some of the sorbents being proposed in the open literature might need to be tested under laboratory conditions for tens of thousands of sorption−desorption cycles before they can be further considered as viable options for CO2 capture from power plants.

Modelling of the kinetics of sulphation of CaO particles under CaL reactor conditions

“…Among the technologies developed, the postcombustion calcium looping (CaL) system is one of the most promising due to the economic benefits it offers and experience acquired with similar systems already operating at industrial scale [2][3][4][5][6][7]). One of the main advantages of these emerging CaL technologies is the low cost of the sorbent since natural limestone is used as the preferred source of CaO.…”

“…In this configuration, coal is burned in air in the CFBC, generating a stream of gases that is fed to the CFB carbonator, which operates at around 650 °C. It is here that CO 2 capture takes place since the CaO reacts with CO 2 to form CaCO 3 . The carbonated solids then enter the CFB calciner, where CaO is regenerated to form a rich CO 2 atmosphere typical of oxy combustion at temperatures of around 900 °C [2].…”

The Use of a High Limestone Content Mining Waste as a Sorbent for Co2 Capture

“…Among the promising technologies to separate CO2 by post-combustion capture processes, carbonation-calcination loops use an extremely cheap and abundant regenerable sorbent (Abanades et al, 2004;López-Periago et al, 2013): calcium carbonate. This process is based on the cycles of the gas-solid reaction (carbonation) of calcium oxide with carbon dioxide, forming calcium carbonate (CaCO3) (Barker, 1973;Santos et al, 2012) and the reverse reaction (calcination) to regenerate the CaO, releasing a concentrated stream of CO2 which can be stored or used for other purposes such as dry ice, refrigeration equipment, carbonated beverages and fire extinguishing equipment (Kikkinides and Yang, 1993).…”

Estudo do aproveitamento de resíduo da mineração rico em calcário para captura de dióxido de carbono

“…Uma forma atrativa de realizar esta separação é utilizando o óxido de cálcio, através da realização de ciclos consecutivos das reações carbonatação-calcinação (Nikulshina et al, 2009), sendo a primeira a reação de formação do carbonato de cálcio a partir da reação do óxido de cálcio com o CO 2 e a segunda a reação reversa (Abanades, 2002;Al-Jeboori et al, 2012;Wang et al, 2007). A vantagem deste processo é a utilização de uma matéria-prima abundante e barata (Abanades et al, 2004), já a desvantagem é o fato da capacidade de captura diminuir aolongo dos ciclos de reações (Rhida et al, 2012;Fennell et al, 2007), devido principalmente à sinterização decorrente da etapa de calcinação. A fim de amenizar este problema, pode-se incluir uma etapa intermediária de hidratação do CaO (Phalak et al, 2012), a qual contribui para aumentar o volume dos poros.…”