Carbonation and deactivation kinetics of a mixed calcium oxide–copper oxide sorbent/oxygen carrier for post-combustion carbon dioxide capture

An engineering design for a novel 1-kW solar-driven reactor to capture carbon dioxide via the calcium oxide-based two-step carbonation–calcination cycle has been completed. The reactor consists of a downward-facing cylindrical dual cavity. The inner cavity serves as the radiation receiver, while the outer cavity is the reaction chamber that contains a packed- or fluidized-bed of reacting particles. Several aspects have been incorporated in this reactor design, including high flexibility, mechanical rigidity and simplicity, high-temperature and thermal shock resistance, accommodation of thermal expansion, low convective heat losses, uniform gas distribution inside the reaction chamber, and simple reactor assembly. The final reactor design is presented, and the reactor assembly is illustrated.

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Hydrate-Based Carbon Capture Process: Assessment of Various Packed Bed Systems for Boosted Kinetics of Hydrate Formation

Journal of Energy Resources Technology ◽

10.1115/1.4048304 ◽

2020 ◽

Vol 143 (3) ◽

Cited By ~ 1

Author(s):

Amit Arora ◽

Asheesh Kumar ◽

Gaurav Bhattacharjee ◽

Chandrajit Balomajumder ◽

Pushpendra Kumar

Keyword(s):

Carbon Dioxide ◽

Carbon Capture ◽

Carbon Dioxide Capture ◽

Fixed Bed ◽

Hydrate Formation ◽

Packed Bed ◽

Fixed Bed Reactor ◽

Capture Process ◽

Novel Technologies ◽

Kinetics Of

Abstract The case for developing novel technologies for carbon dioxide (CO2) capture is fast gaining traction owing to increasing levels of anthropogenic CO2 being emitted into the atmosphere. Here, we have studied the hydrate-based carbon dioxide capture and separation process from a fundamental viewpoint by exploring the use of various packed bed media to enhance the kinetics of hydrate formation using pure CO2 as the hydrate former. We established the fixed bed reactor (FBR) configuration as a superior option over the commonly used stirred tank reactor (STR) setups typically used for hydrate formation studies by showing enhanced hydrate formation kinetics using the former. For the various packing material studied, we have observed silica gel with 100 nm pore size to return the best kinetic performance, corresponding to a water to hydrate conversion of 28 mol% for 3 h of hydrate growth. The fundamental results obtained in the present study set up a solid foundation for follow-up works with a more applied perspective and should be of interest to researchers working in the carbon dioxide capture and storage and gas hydrate fields alike.

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Chemical-Looping Combustion of Hard Coal: Autothermal Operation of a 1 MWth Pilot Plant

Journal of Energy Resources Technology ◽

10.1115/1.4032357 ◽

2016 ◽

Vol 138 (4) ◽

Cited By ~ 42

Author(s):

Peter Ohlemüller ◽

Jan-Peter Busch ◽

Michael Reitz ◽

Jochen Ströhle ◽

Bernd Epple

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Capture ◽

Oxygen Carrier ◽

Air Separation ◽

Capture Efficiency ◽

Chemical Looping Combustion ◽

Hard Coal ◽

Chemical Looping ◽

Separation Unit ◽

Autothermal Operation

Chemical-looping combustion (CLC) is an emerging carbon capture technology that is characterized by a low energy penalty, low carbon dioxide capture costs, and low environmental impact. To prevent the contact between fuel and air, an oxygen carrier is used to transport the oxygen needed for fuel conversion. In comparison to a classic oxyfuel process, no air separation unit is required to provide the oxygen needed to burn the fuel. The solid fuel, such as coal, is gasified in the fuel reactor (FR), and the products from gasification are oxidized by the oxygen carrier. There are promising results from the electrically heated 100 kWth unit at Chalmers University of Technology (Sweden) or the 1 MWth pilot at Technische Universität Darmstadt (Germany) with partial chemical-looping conditions. The 1 MWth CLC pilot consists of two interconnected circulating fluidized bed reactors. It is possible to investigate this process without electrically heating due to refractory-lined reactors and coupling elements. This work presents the first results of autothermal operation of a metal oxide CLC unit worldwide using ilmenite as oxygen carrier and coarse hard coal as fuel. The FR was fluidized with steam. The results show that the oxygen demand of the FR required for a complete conversion of unconverted gases was in the range of 25%. At the same time, the carbon dioxide capture efficiency was low in the present configuration of the 1 MWth pilot. This means that unconverted char left the FR and burned in the air reactor (AR). The reason for this is that no carbon stripper unit was used during these investigations. A carbon stripper could significantly enhance the carbon dioxide capture efficiency.

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