The effect of CaO sintering on cyclic CO₂ capture in energy systems

Abstract

in Wiley InterScience (www.interscience.wiley.com).The importance of calcium-based sorbents, especially natural limestones, for CO 2 removal necessitates an investigation into the sorbent decay mechanism. This study starts from pore size distributions for samples from tests under various calcination/carbonation cycling conditions. A sintering model is formulated to describe the cyclic behavior of sorbents during cyclic calcination and carbonation. It explains the similar reversibility shown by sorbents under different test conditions. A balance between shorter cumulative sintering time and higher calcination rates appears to be responsible for the similar degrees of sintering and sorbent reversibility. 2007 American Institute of Chemical Engineers AIChE J,

Degradation study of a novel polymorphic sorbent under realistic post-combustion conditions

“…× 100% (6) Here C is the carrying capacity, also referred to as CaO conversion, mol CO2 / mol CaCO3, nCO 2 is the total number of moles of CO2 released during the calcination reaction, calculated from the mass change and the relative molecular mass (RMM), RMMCaCO 3 is the relative molecular mass of CaCO3, Three repeats of all experiments were carried out and the standard deviation at each cycle was calculated to provide an estimation of error, this error can be seen as error bars in figure 2.…”

“…However, the carrying capacity of limestone derived sorbents degrades over multiple reaction cycles, eventually leading to a carrying capacity of approximately 0.1 -0.2 gCO2/gCaO (this value can be reached in as few as 20 cycles) [5] [6]. The cause of this loss of carrying capacity is primarily due to sintering, which has been shown to occur by reactive and thermal sintering, thermal softening and the coalescence of smaller grains into larger grains, this results in the loss of a fine pore structure and a shift from smaller micro-and meso-pores to larger macro-pores which are less useful for the capture of CO2 [7] [8].…”

Reaction-driven casing expansion: potential for wellbore leakage mitigation

“…Second, in the present study we prepared our CaO by calcining Carrara marble at 1100°C for 16 h. There exists a substantial body of literature dealing with the effects of calcination temperature, starting carbonate material and grain size, and various other processes (e.g. sintering) on the nature of the final CaO product [13,14,41,46,112]. For example, the rate of hydration is slower for dead-burnt lime (calcined at [1600°C) than for ''normal'' CaO, prepared at\1200°C [43].…”

Captura De Dióxido De Carbono Utilizando Óxidos a Base De Cálcio

“…No entanto, a grande desvantagem do CaO é a perda da área superficial pela exposição do sólido aos ciclos de carbonatação e decomposição, os quais são realizados em altas temperaturas. A perda da área superficial deve-se ao fenômeno de sinterização do material (Lu et al, 2014;Sun et al, 2007).…”