Article
Green & Sustainable Science & Technology
Giuseppe Cristian Piso, Piero Bareschino, Paola Brachi, Claudio Tregambi, Giovanna Ruoppolo, Francesco Pepe, Erasmo Mancusi
Summary: In this study, the Chemical Looping Reforming of biogas was proposed and numerically investigated to achieve the clean, efficient, and cost-effective utilization of renewable carbonaceous fuels. The effects of biogas composition and process parameters on the reaction performances were assessed and discussed, including the conversion degree, syngas yield, and syngas composition.
Review
Energy & Fuels
Chen Ge, Shiyuan Li, Linwei Wang
Summary: Oxy-fuel circulating fluidized bed combustion (Oxy-CFBC) is a promising and sustainable technology for carbon capture, utilization, and sequestration in coal-fired power plants. In the past 15 years, research on Oxy-CFBC has rapidly developed, from lab-scale to industrial-scale facilities. This paper reviews the research status of Oxy-CFBC, including models, heat transfer, combustion characteristics, pollutant formation and emission, and system optimization. It also analyzes different fuels and the differences in NOx emission and desulfurization mechanism between air combustion and oxy-combustion modes. The review highlights the importance of gas staging and oxygen staging in reducing NO emissions, and discusses new generation technologies and challenges for future research and industrial application of Oxy-CFBC.
Article
Thermodynamics
Junjie Lin, Liyan Sun, Kun Luo, Dali Kong, Jianren Fan
Summary: In this study, three-dimensional simulations were used to investigate the flow behavior and reaction characteristics of a chemical looping combustion system. The numerical models developed in this work can be utilized for system design and scale-up, and the operating temperature and solid inventory have significant effects on system performance.
Article
Chemistry, Physical
Rei-Yu Chein, Wei-Feng Tseng, Keng-Tung Wu
Summary: Chemical-looping combustion (CLC) is a promising technique for capturing carbon dioxide efficiently and economically. This study uses numerical simulation to compare the performance of conventional bubbling fluidized bed (BFB) fuel reactor and internal circulation bubbling fluidized bed reactor (ICBFB). The results show that the use of ICBFB can enhance the reduction reaction by increasing particle circulation and improving mixing and contact time between fuel and oxygen carrier.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Review
Energy & Fuels
Hengjun Gai, Peiyi Yang, Qiang Zhang, Mengqi Lin, Hongbing Song, Meng Xiao, Tingting Huang, Quanhong Zhu
Summary: Circulating fluidized bed reactors are widely used in the energy industry for gas-solid reactions. They can be classified into two categories based on fluidization regimes: dilute-dense and dual-dense. The concept of dual-dense gas-solid circulating fluidization has not been well understood, hindering its commercial application. This review provides a detailed analysis of the dual-dense system, including mechanism, structural and operating parameters, particle circulation prediction, gas-solid flow simulation, and potential applications, while identifying existing controversies and unresolved issues.
Article
Green & Sustainable Science & Technology
Edoardo De Lena, Borja Arias, Matteo C. Romano, J. Carlos Abanades
Summary: This study investigates a Calcium Looping (CaL) configuration for cement plants using two interconnected circulating fluidized bed (CFB) reactors. The proposed system combines calcination and fragmentation of limestone in a single unit, taking advantage of the limestone's tendency to attrition. The economic analysis shows that this configuration is competitive.
INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL
(2022)
Article
Energy & Fuels
Petteri Peltola, Falah Alobaid, Tero Tynjaelae, Jouni Ritvanen
Summary: This article provides a brief review of the modeling of chemical looping combustion (CLC), a next-generation CO2 capture technology, in bubbling and circulating fluidized bed reactors. The article presents a summary of published mathematical reactor models, with a focus on a macroscopic modeling approach that combines transport equations with semiempirical correlations to describe key fluidized bed phenomena. The article highlights important aspects to be considered in the modeling of CLC in a dual fluidized bed reactor system and identifies research needs. So far, semiempirical reactor models have been validated based on experimental results, but there is limited research on dynamic process simulation of CLC.
Review
Engineering, Chemical
Sama Manzoor, James Tatum, Omar B. Wani, Erin R. Bobicki
Summary: The study of comminution of carbonaceous solids during the fluidized bed combustion process is crucial for understanding combustion rate, thermal efficiency, and particle size distribution. The comminution process in a fluidized bed reactor involves a sequence of events including primary fragmentation, secondary fragmentation, percolative fragmentation, and attrition. It has been shown that comminution significantly affects carbon conversion efficiency and incomplete carbon conversion leads to reduced fuel residence time and thermal efficiency. This paper aims to provide an updated overview of recent studies on comminution of carbon-based fuels in a fluidized bed reactor, discussing different types of comminutions, their impacts on reactor efficiency, and factors affecting particle fragmentation. The findings emphasize the importance of considering comminution phenomena in order to accurately assess fuel particle size and distribution in the reactor for increasing conversion efficiency.
MINERALS ENGINEERING
(2023)
Article
Energy & Fuels
Ivan Gogolev, Toni Pikkarainen, Juho Kauppinen, Carl Linderholm, Britt-Marie Steenari, Anders Lyngfelt
Summary: Chemical looping combustion (CLC) of biomass is a promising technology for power generation with integrated carbon capture, but the alkali content of biomass may lead to bed agglomeration and oxygen carrier absorption issues. Studies have shown that gas-phase alkali emissions in CLC operation can be up to 15 times higher than in OCAC operation, mainly due to steam accelerating the decomposition of alkali compounds in the biomass.
Article
Energy & Fuels
Yan Shi, Wenqi Zhong
Summary: By conducting a comprehensive life-cycle environmental and economic assessment of oxy-coal combustion with circulating fluidized bed power plants with a pressurized combustor and a supercritical CO2 Brayton cycle, it was found that the systems have lower damage to human health and the environment, as well as relatively lower costs of electricity, CO2 capture, and CO2 avoidance. The study also discusses the impact of various parameters on economic indicators.
Article
Energy & Fuels
Mais Baqain, Can Rustu Yoruk, Dmitri Nesumajev, Oliver Jarvik, Alar Konist
Summary: The CO2-intensive oil shale power industry in Estonia produces a significant amount of ash, which is mainly disposed of in landfills. Switching to oxy-fuel technology with CO2 storage can help reduce carbon footprint. However, there are expected differences in ash formation under oxy-fuel conditions, leading to additional challenges in ash handling and environmental concerns.
Article
Energy & Fuels
Ratnakumar V. Kappagantula, Gordon D. Ingram, Hari B. Vuthaluru
Summary: Chemical Looping Combustion technologies have the ability to capture carbon dioxide and are modeled using a specialized Fluidized Bed Reactor block in Aspen Plus. Sensitivity studies showed that solid volume fraction decreases with bed height and superficial velocity, while the height to diameter ratio of the fluidized bed is an important variable in reactor design.
Article
Green & Sustainable Science & Technology
Ningbo Gao, Maciej Sliz, Cui Quan, Artur Bieniek, Aneta Magdziarz
Summary: The study found that a 2:1 ratio of N-2 to CO2 at 700 degrees Celsius resulted in a 25% reduction in CO2. The catalytic properties of CaO increased the concentration of H-2 in the produced syngas by up to 10%. However, a temperature of 800 degrees Celsius was too high for the carbonation reaction of CaO.
Article
Energy & Fuels
Joseba Moreno, Sally L. Homsy, Max Schmid, Gunter Scheffknecht
Summary: This study investigated the multicyclic behavior of limestone in a 20 kWth CaL facility and analyzed the performance of the carbonator under various process variables. The carbonator design achieved high CO2 capture efficiencies and apparent carbonation rates within the investigated operating conditions. The proposed design could potentially be integrated into existing load-following power plants for more flexible usage of CaL systems.
Article
Energy & Fuels
Wan Zhang, Yingjie Li, Shoubing Chai, Zirui He, Chunxiao Zhang, Dong Wang
Summary: In this study, Mn-doped CaO was found to significantly improve the efficiency of CO for NO removal and CO2 capture in the calcium looping process. The presence of Mn enhanced the catalytic effect of CaO, leading to higher NO removal efficiency and CO2 capture capacity. The results suggest that Mn-doped CaO could be a promising material for achieving simultaneous NO removal and CO2 capture in the carbonation stage of the process.
Article
Engineering, Environmental
Jae-Young Kim, Je-Min Woo, Sung-Ho Jo, Hyunuk Kim, Seung-Yong Lee, Chang-Keun Yi, Jong-Ho Moon, Hyungseok Nam, Yooseob Won, Lee A. Stevens, Chenggong Sun, Hao Liu, Jingjing Liu, Colin E. Snape, Young Cheol Park
Summary: The study reported the continuous 150-hour test using silica-PEI on a fluidized bed unit, demonstrating its potential for CO2 capture and evaluating the efficiency and capacity. Results showed over 90% CO2 removal efficiency and 7.5 wt% dynamic sorption capacity achieved during continuous operation.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Multidisciplinary
Xiangchen Qian, Fengjie Li, Yong Yan, Gang Lu, Hao Liu
Summary: The combustion characteristics of individual coal particles were studied with a quantitative method using digital images to measure physical parameters. The experimental results showed that volatile and char combustion occurred successively, with volatile matter being combusted rapidly. The particles exhibited different rotations frequencies at different combustion phases, and traveled upwards due to devolatilisation and volatile combustion influences.
MEASUREMENT SCIENCE AND TECHNOLOGY
(2021)
Article
Thermodynamics
Lei Pang, Yingjuan Shao, Wenqi Zhong, Hao Liu
Summary: Experimental studies on pressurized oxy-coal combustion in fluidized bed combustors/boilers with continuous coal feeding are limited, but have shown that an increase in pressure can significantly improve combustion efficiency and combustion rate of coal particles, with a more pronounced effect on high rank coal and high O2 concentration. Under high pressure oxy-coal combustion conditions, NOx emissions decrease while N2O emissions increase, with SO2 emissions minimally impacted by pressure but direct desulfurization of limestone enhanced with pressure.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Energy & Fuels
Hetian Chi, Miguel A. Pans, Mingwen Bai, Chenggong Sun, Tanvir Hussain, Wei Sun, Yuge Yao, Junfu Lyu, Hao Liu
Summary: Stellite-6 demonstrated excellent corrosion resistance with the formation of protective Cr2O3 and CoCr2O4 layers, while NiAl coatings showed significantly reduced anti-corrosion performance due to chlorine attack, resulting in the formation of Al2O3 layer and eventual coating spallation in both systems.
Article
Energy & Fuels
Yanyi Sun, Xin Liu, Yang Ming, Xiao Liu, Daniel Mahon, Robin Wilson, Hao Liu, Philip Eames, Yupeng Wu
Summary: This research introduces a novel multi-effect smart window system that integrates a thermotropic material with a transparent insulation material to enhance energy efficiency and improve indoor luminous environment. The simulation results show that installing this window system can yield significant energy savings and increase daylight availability under different climate conditions. Future research can focus on material design and development to further enhance energy efficiency and solar and daylight control.
Article
Energy & Fuels
E. Emilia Rios-Del Toro, Hetian Chi, Victor Gonzalez-Alvarez, Hugo O. Mendez-Acosta, Jorge Arreola-Vargas, Hao Liu
Summary: The tequila industry waste presents both environmental challenges and economic opportunities. This study demonstrates the potential of integrating biochemical and thermochemical platforms for the full conversion of Agave tequilana bagasse, aiming to enhance energy recovery and product utilization.
Article
Construction & Building Technology
Yanyi Sun, Robin Wilson, Hao Liu, Yupeng Wu
Summary: Smart window designs incorporating thermotropic and Transparent Insulation Material (TIM) can improve building energy efficiency and achieve homogeneous daylight distribution. The geometric configurations and thermotropic features play a significant role in energy and daylight performance.
BUILDING AND ENVIRONMENT
(2021)
Article
Thermodynamics
Eduardo Garcia, Hao Liu
Summary: The study found that using ilmenite as the bed material can reduce CO emissions, decrease efficiency loss, but increase NOx emissions. Ilmenite can also reduce the size of agglomerates and decrease the tendency towards defluidisation.
Article
Green & Sustainable Science & Technology
Hetian Chi, Miguel A. Pans, Chenggong Sun, Hao Liu
Summary: In this study, the use of molochite and dolomite as bed additives in a fluidised bed combustor was investigated to counter agglomeration during the combustion of wheat straw and miscanthus pellets. The results showed that dolomite was superior to molochite in prolonging defluidisation time when firing wheat straw. Lime addition to fuel had the most significant improvement on combustion performance for both fuels. The oxy-fuel combustion atmosphere had a great impact on the effectiveness of dolomite but little influence on the effectiveness of molochite.
Article
Energy & Fuels
Eduardo Garcia, Manuel F. Mejia, Hao Liu
Summary: The co-combustion of coal and waste coffee grounds is a sustainable and environmentally friendly option for waste disposal and energy production. This study investigated the combustion characteristics of coal blended with coffee grounds and found that coffee grounds can reduce the efficiency loss of coal combustion and minimize agglomeration tendency.
Article
Thermodynamics
Eduardo Garcia, Ikechukwu F. Ejim, Hao Liu
Summary: This study investigates the combustion characteristics of blends of bituminous coal with by-products of the coffee industry. The results show that blending spent coffee ground and coffee husk with bituminous coal can enhance the ignition and combustion indices, with clear synergistic effects observed in the combustion of bituminous coal-spent coffee ground blends.
THERMOCHIMICA ACTA
(2022)
Article
Thermodynamics
Zhaozhi Li, Yingjuan Shao, Wenqi Zhong, Hao Liu
Summary: This study focuses on the optimal design of the supercritical CO2 Brayton cycle for oxy-coal power plants, which has not received much attention in research. A novel triple recompression sCO2 cycle and a new sCO2 oxy-coal CFB boiler configuration were proposed and evaluated. The results showed that the novel configuration and triple recompression cycle could increase system efficiency by about 1.4% points compared to the basic system.
Article
Construction & Building Technology
Murtaza Mohammadi, John Kaiser Calautit, John S. Owen, Christof Gromke, Yupeng Wu, Hao Liu
Summary: This study investigates the wind-driven transmission of pollutants between indoor rooms adjacent to a street canyon. It found that the ventilation efficiency and room location have an impact on the transmission. Increasing ventilation rate can reduce cross transmission between rooms, while rooms at the center of the canyon are more susceptible to contamination.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Environmental
Mengbin Li, Xin Liu, Chenggong Sun, Lee Stevens, Hao Liu
Summary: This study successfully prepared a series of advanced bio-carbon materials using the underutilized industrial by-product Kraft lignin as a precursor through a facile chemical activation process. The properties of these bio-carbons were highly tailorable by adjusting the activation conditions, and they exhibited outstanding CO2 adsorption performance and high CO2/N2 selectivity at low CO2 partial pressures. The results indicate that the unique three-dimensional aromatic structures of lignin contributed to the development of high-level ultra-microporosity.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Energy & Fuels
Ligang Xu, Yaji Huang, Junfeng Yue, Lu Dong, Lingqin Liu, Jianrui Zha, Bo Chen, Zhicheng Zhu, Hao Liu
Summary: The research proposed a dynamic slagging monitoring model based on neural networks and genetic algorithms, and formulated a corresponding optimization strategy for soot-blowing, achieving effective monitoring of slagging on the waterwall and optimization of soot-blowing operations.
JOURNAL OF THE ENERGY INSTITUTE
(2021)
