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This paper presents the modeling and simulation of an industrial-scale chemical looping combustion (CLC) power plant, including all process units (reactors, flue gas treatment units, heat integration, steam cycle, and CO2 compression train). A model of a 525 MWth CLC power plant was built using a rigorous representation of the solid fuel and oxygen carrier. Petcoke was considered the main fuel of interest in this study, and it is compared with other solid fuels. The flue gas compositions obtained with the model show that cleanup units are mandatory to comply with CO2 quality requirements. High levels of flue gas treatment, including 97.1% deNOx and 99.4% deSOx, are needed to achieve typical specifications for captured CO2. This is mainly due to the high level of contaminants in the fuel, but also to the absence of nitrogen in the CLC flue gas, thus resulting in higher concentrations for all substances. The high level of flue gas treatment is thus one of the important challenges for solid fuel combustion in CLC. The overall CO2 capture efficiency of the plant is estimated to be as high as 94%. Regarding the energy balance, a process net efficiency of 38% is obtained. Comparing the results with other available technologies shows that CLC exhibits one of the highest net plant efficiencies and carbon capture rates. CLC is thus a promising technology to produce clean energy from solid fuels. Finally, based on a sensitivity analysis, it is shown that process efficiency is mainly affected by the design and performance of the CLC furnace, the steam injection rate in the fuel reactor, the char separation efficiency, and the excess oxygen in the air reactor. [ABSTRACT FROM AUTHOR]

• The world's largest Chemical Looping Combustion (CLC) demonstration unit is ready for start-up. • CLC seems to be the most cost-effective technology for power production based on solid fuels with carbon capture. • Building large units as a collaborative effort across continents is complicated, but may be both beneficial and very rewarding when all partners work closely together. The world's largest Chemical Looping Combustion (CLC) demonstration unit is being built close to the city of Chengdu in China. The design and construction of the unit, as well as the coming testing, is done within the CHEERS project, which is a collaborative project between Europe and China. The funding (∼25M€) comes from several of the project partners, in addition to EU's Horizon2020 and China's Ministry of Science and Technology (MOST). TotalEnergies has been responsible for the Front-End Engineering Design (FEED) study. The investment decision from December 2021 marks the transition from the R&D studies and design phases to Engineering, Procurement, Construction (EPC) and testing phase. The EPC phase has been led by Dongfang Boiler Co.,Ltd, and the demonstration unit is located at their technology development site in Deyang City, outside Chengdu in China. It is designed for a thermal input of 2–4 MW and includes two different reactor configurations. The first configuration is optimized for conversion of pet-coke, while the second one is tuned towards conversion of lignite. The oxygen carrier (OC) that will be used for the demonstration unit (ilmenite) will be presented, together with an overview of the various OC materials that were tested at various scales (up to 150 kWth) during the first part of the project. In addition, results from testing of a cold mock-up of the unit is presented. Finally, an overview of plans for the rest of the project is given, together with some thoughts related to intercontinental collaboration in highly collaborative projects, such as CHEERS. [ABSTRACT FROM AUTHOR]

Chemical Looping Combustion (CLC) is conventionally carried out in circulating fluidized bed systems involving various kinds of fluidized beds and solid handling devices. Scale-up of these systems is a research and development challenge associated with various risks and uncertainties. Gas bypassing, poor gas–solid contact and poor performance of solid circulation control devices are among the major considerations in this regard. This paper presents impacts of temperature on the fluidization properties in CLC application. Impacts of temperature on the minimum fluidization velocity and the onset of turbulent regime are studied in various temperatures up to 900 °C. Increase of temperature decreases the minimum fluidization velocity and increases the onset of transition to turbulent regime. Impact of size and temperature on the performance of pneumatic valves (L-valve and loop-seal) are investigated using valves in a range of 2–24 cm in a temperature range of 25–750 °C. Geldart group B particles of 100–300 μm and density of 2600–4750 kg/m 3 are used in these experimental tests. [ABSTRACT FROM AUTHOR]

Cyclones are commonly used in the process industry to separate entrained particles from gas streams. Particles entering a cyclone are subjected to a centrifugal force field, driving them to the cyclone walls, where they experience collisional and rapid shearing stresses. Consequently, particle attrition and erosion of the cyclone walls occur, depending on the mechanical properties of the particles and cyclone walls. In this work, the attrition of manganese oxide particles, intended for use in the Chemical Looping Combustion (CLC) process, flowing through a standard design cyclone (Stairmand design) is analysed as an example by considering surface damage processes of chipping and wear. A new methodology is developed, whereby Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) simulations are used to analyse the particle motion and interactions with the cyclone walls. The approach is then coupled with breakage models of chipping and wear to predict the extent of attrition. The impact breakage due to chipping is evaluated experimentally first as a function of particle size and impact angle and velocity. The data are fitted to the chipping model of Ghadiri and Zhang. The model is then coupled with the frequency of collisions and impact velocity, obtained from the CFD-DEM simulation, to work out the particle attrition by chipping. For surface wear the model of Archard is used to account for particle wear by shearing against the walls. The outcome of the work provides a methodology for describing the extent of attrition in different regions of the cyclone. Unlabelled Image • Particle attrition in a cyclone is analysed by CFD-DEM. • Particle breakage by chipping and surface abrasion is considered. • Crushed manganese oxide is used as a model material. • Single particle impact attrition is first evaluated experimentally. • The overall attrition rate is predicted by coupling breakage data with DEM. [ABSTRACT FROM AUTHOR]

A promising copper based oxygen carrier produced using industrially-relevant manufacturing equipment has been aged in IFPEN’s 10 kW th Chemical Looping Combustion pilot plant. Methane combustion was performed at 900 °C for 160 h with an OC/fuel ratio of 1.2. While full methane conversion to CO 2 and water was achieved in the early stage of the experiment, fast deactivation was observed. The oxygen carrying particles were thoroughly characterized at various stages of the ageing experiment, from which a pathway leading to deactivation is proposed. [ABSTRACT FROM AUTHOR]