Combined oxides as oxygen-carrier material for chemical-looping with oxygen uncoupling

Rydén, Magnus; Leion, Henrik; Mattisson, Tobias; Lyngfelt, Anders

doi:10.1016/j.apenergy.2013.06.016

Cited by 236 publications

(160 citation statements)

References 41 publications

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“…This is because complete conversion of fuel is possible both for reduction of Mn 2 Manganese (III) oxide also has the ability to release oxygen directly in gaseous form in inert atmosphere at temperatures around 800 • C [3]. For manganese ores, which are not pure but also contain elements such as iron and silicon, other more favourable mechanisms for oxygen release that work at higher temperatures could also be available [10,11].…”

Section: Manganese Ore As Oxygen Carriermentioning

confidence: 99%

Oxygen Carrier Aided Combustion (OCAC) of Wood Chips in a Semi-Commercial Circulating Fluidized Bed Boiler Using Manganese Ore as Bed Material

et al. 2016

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Abstract:Oxygen Carrier Aided Combustion (OCAC) is realized by using an active oxygen-carrying bed material in fluidized bed boilers. The active material is reduced in fuel rich parts of the boiler and oxidized in air rich parts. Advantages could be achieved such as new mechanisms for oxygen transport in space and time. Here calcined manganese ore has been used as active bed material in a 12 MW th circulating fluidized bed boiler. The fuel was wood chips and the campaign lasted more than two weeks. From an operational point of view, manganese ore worked excellently. From the temperature profile of the boiler it can be concluded that fuel conversion was facilitated, especially in the dense bottom bed. The effect did not always translate to reduced emissions, which suggests that final combustion in the cyclone outlet was also influenced. Substituting 10% of the sand bed with manganese ore made it possible to reduce the air to fuel ratio without generating large amounts of CO. The use of 100% manganese ore resulted in higher emissions of CO than the sand reference, but, when combined sulphur feeding, dramatic reductions in CO emissions, up to 90% compared to sand reference, was achieved.

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Section: Manganese Ore As Oxygen Carriermentioning

confidence: 99%

Oxygen Carrier Aided Combustion (OCAC) of Wood Chips in a Semi-Commercial Circulating Fluidized Bed Boiler Using Manganese Ore as Bed Material

et al. 2016

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“…Cu-based [2][3][4] and Mn-based materials mixed with Ca, Mg, Cu, Ni, Fe or Si [5] have focused great attention. Adánez et al [6] and Mattisson [7] summarize the oxygen carrier developed for CLOU and the facilities where have been tested.…”

Section: Introductionmentioning

confidence: 99%

Kinetic analysis of a Cu-based oxygen carrier: Relevance of temperature and oxygen partial pressure on reduction and oxidation reactions rates in Chemical Looping with Oxygen Uncoupling (CLOU)

Adánez-Rubio

Gayán

Abad

et al. 2014

Chemical Engineering Journal

103

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The kinetic of reduction of CuO to Cu 2 O with N 2 +O 2 mixtures and the oxidation of Cu 2 O to CuO with O 2 of a Cu-based oxygen carrier for the CLOU process has been determined in a TGA. For kinetic determination, the O 2 concentrations were varied between 0 and 9 vol.% for reduction, and between 21 and 1.5 vol.% for oxidation reactions; temperature was varied between 1148 and 1273 K for the reduction and between 1123 and 1273 K for the oxidation. The oxygen carrier showed high reactivity 2 both in oxidation and reduction reactions. The nucleation and nuclei growth model with chemical reaction control properly described the evolution of solids conversion with time. The Langmuir-Hinshelwood model was able to describe the effect of oxygen concentration on reduction and oxidation rates. The reaction order was 0.5 for reduction and 1.2 for the oxidation. The kinetic constant activation energies were 270 kJ mol -1 for the reduction and 32 kJ mol -1 for the oxidation. The kinetic model was used to calculate the solids inventory needed in the fuel reactor for complete combustion of three different rank coals. It was possible to use a low oxygen carrier inventory in the fuel reactor (160 kg/MW th ) to supply the oxygen required to full lignite combustion.However, to reach high CO 2 capture efficiencies (³95%), oxygen carrier inventories in fuel reactor higher than 600 kg/MW th were needed with the lignite.

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“…More recently, the literature has highlighted the potential use of more complex materials, such as perovskite-type oxides [7,8], spinel-type oxides [9][10][11][12], and mixed-metal oxides [4,13,14]. However, these studies were limited.…”

Section: Introductionmentioning

confidence: 99%

“…Successful examples of natural oxygen carriers have been found in some natural ores, such as an iron ore from Carajas, Malmberget or LKAB in [14], and a waste iron oxide that is a residual product from the rolling of steel sheets that consist mostly of Fe 2 O 3 and Fe 3 O 4 , such as Glödskal A [14]. Several suitable low-cost Fe-based oxygen carriers have been identified [17] that exhibit higher syngas (50 % H 2 /50 % CO) conversion rates than those rates that were obtained using ilmenite.…”

Section: Introductionmentioning

confidence: 99%

Studies on the redox reaction kinetics of selected, naturally occurring oxygen carrier

Ksepko

Babiński

Evdou

et al. 2015

J Therm Anal Calorim

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This paper presents the results of a chemicallooping combustion (CLC) study. The CLC technology is believed to be one of the most promising combustion technologies. The production of a concentrated CO 2 stream that is obtained after the water condensation without any loss of energy in its separation is one of the most crucial advantages of this technology. The objective of this work was to study the kinetics of both the reduction and oxidation reactions for naturally occurring oxygen carriers that show promising reactivity in CLC reactions, and might therefore be utilized as oxygen carrier materials. Kryvbas, a Fe-based ore, was selected for this analysis because it possessed sufficient concentrations of the active metal oxides (Fe oxide above 80 % and traces of Mn oxide) and a high melting temperature that was above 1500°C. Experiments were conducted under isothermal conditions within the temperature range of 750-950°C with multiple redox cycles using a thermogravimetric analyzer (TG). For the reduction and oxidation reactions, CH 4 (at different concentrations) and air were used, respectively. The sample showed promising results where a sufficient reactivity was observed with the fuel, and these results were reproducible. Both fresh material and samples that were used in multiple redox cycles were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy combined with X-ray Microanalysis (SEM-EDS) in order to detect any structural or morphological changes as well as to determine the stability of the ore in repetitive CLC cycles. Kinetic parameters, such as the activation energy, the preexponential factor, and the reaction model, were determined for the redox reactions. Models of the redox reactions were selected by using a model fitting method. The F1 model (volumetric) was a suitable model for the modeling of the Kryvbas ore reduction reaction kinetics. The calculated E a was equal to 42.00 kJ mol -1 , while the reaction order was determined to be equal to 1.98. The best fit for the oxidation reaction was obtained for the R3 model (shrinking core model). The oxidation (regeneration) reaction activation energy was equal to 16.70 kJ mol -1 , and the reaction order was determined to be equal to approximately 0.49.

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Combined oxides as oxygen-carrier material for chemical-looping with oxygen uncoupling

Cited by 236 publications

References 41 publications

Oxygen Carrier Aided Combustion (OCAC) of Wood Chips in a Semi-Commercial Circulating Fluidized Bed Boiler Using Manganese Ore as Bed Material

Oxygen Carrier Aided Combustion (OCAC) of Wood Chips in a Semi-Commercial Circulating Fluidized Bed Boiler Using Manganese Ore as Bed Material

Kinetic analysis of a Cu-based oxygen carrier: Relevance of temperature and oxygen partial pressure on reduction and oxidation reactions rates in Chemical Looping with Oxygen Uncoupling (CLOU)

Studies on the redox reaction kinetics of selected, naturally occurring oxygen carrier

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