The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
Calin-cristian Cormos - One of the best experts on this subject based on the ideXlab platform.
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Mathematical modeling and simulation of gasification processes with Carbon Capture and Storage (CCS) for energy vectors poly-generation
Computer-aided chemical engineering, 2020Co-Authors: Victoria Maxim, Calin-cristian Cormos, Ana-maria Cormos, Serban AgachiAbstract:Abstract Gasification of Solid fuels is a partial oxidation process which converse the Solid Feedstock into syngas which can be used in a large number of applications e.g. power generation, manufacture of various chemicals and fuels (hydrogen, methanol, ammonia, fertilizers etc.). Not all of the gasification systems are suitable for energy vectors polygeneration with carbon capture and storage (CCS). This paper is proposing to evaluate various gasification technologies by mathematical modeling and simulation methods (especially for entrained flow types as these gasifiers are more suitable for implementing carbon capture technologies). In this paper a particular accent will be put on the selection of the most promising gasifier, as not all are appropriate for a carbon capture Integrated Gasification Combined Cycle (IGCC) applied for energy vectors poly-generation (with a particular focus on hydrogen and electricity co-production case) with Carbon Capture and Storage (CCS). For the selection of the most appropriate gasifier technologies the process were mathematical modeled and simulated with process flow modeling software (e.g. ChemCAD, Aspen). In the evaluation of various gasification technologies (e.g. Shell, Siemens, GE-Texaco, Conoco-Phillips etc.) a multi-criteria analysis was performed.
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Techno-economical and environmental evaluations of IGCC power generation process with carbon capture and storage (CCS)
Computer-aided chemical engineering, 2020Co-Authors: Calin-cristian Cormos, Ana-maria Cormos, Paul Serban AgachiAbstract:Abstract Integrated Gasification Combined Cycle (IGCC) is a power generation technology in which the Solid Feedstock (coal, lignite, biomass etc.) is partially oxidized with oxygen and steam to produce syngas. In a conventional IGCC design for power generation without carbon capture, the syngas is purified for dust and hydrogen sulphide removal and then sent to a Combined Cycle Gas Turbine (CCGT) for power production. Carbon capture and storage (CCS) technologies are expected to play a significant role in the coming decades for reducing the greenhouse gas emissions. IGCC is one of the power generation technologies having the highest potential to capture carbon dioxide with low penalties in term of plant energy efficiency, capital and operational costs. This paper investigates the most important techno-economical and environmental indicators (e.g. net and gross power output, ancillary power consumption, plant efficiency, specific capital cost investment, operational costs, specific carbon dioxide emissions etc.) for power generation with CCS applied to an IGCC scheme. The coal-based IGCC case study investigated in the paper produces around 400 MW net electricity with 90 % carbon capture rate. Similar power plant schemes without carbon capture step were used as references for comparison.
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Integrated assessment of IGCC power generation technology with carbon capture and storage (CCS)
Energy, 2012Co-Authors: Calin-cristian CormosAbstract:IGCC (Integrated Gasification Combined Cycle) is a power generation technology in which the Solid Feedstock is partially oxidized with oxygen and steam to produce syngas. In a conventional IGCC design without carbon capture, the syngas is purified for dust and hydrogen sulphide removal and then it is sent to a CCGT (Combined Cycle Gas Turbine) for power generation. CCS (Carbon capture and storage) technologies are expected to play a significant role in the coming decades for reducing the greenhouse gas emissions. IGCC is one of the power generation technologies having the highest potential to capture CO2 with low penalties in term of plant energy efficiency, capital and operational costs.
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Integrated assessment of IGCC power generation technology with carbon capture and storage (CCS)
Energy, 2012Co-Authors: Calin-cristian CormosAbstract:IGCC (Integrated Gasification Combined Cycle) is a power generation technology in which the Solid Feedstock is partially oxidized with oxygen and steam to produce syngas. In a conventional IGCC design without carbon capture, the syngas is purified for dust and hydrogen sulphide removal and then it is sent to a CCGT (Combined Cycle Gas Turbine) for power generation. CCS (Carbon capture and storage) technologies are expected to play a significant role in the coming decades for reducing the greenhouse gas emissions. IGCC is one of the power generation technologies having the highest potential to capture CO2 with low penalties in term of plant energy efficiency, capital and operational costs. This paper investigates the most important techno-economic and environmental indicators (e.g. power output, ancillary consumption, energy efficiency, CW consumption, normalised mass and energy balances and plant construction materials, capital and O&M (operational & maintenance) costs, specific CO2 emissions, cost of electricity, CO2 removal and avoidance costs etc.) for IGCC with CCS. Coal-based IGCC cases produce around 400–450 MW net electricity with 90% carbon capture rate. Similar IGCC plants without CCS were presented as references. Future IGCC developments for energy vectors poly-generation were also presented.
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Evaluation of power generation schemes based on hydrogen-fuelled combined cycle with carbon capture and storage (CCS)
International Journal of Hydrogen Energy, 2011Co-Authors: Calin-cristian CormosAbstract:Abstract IGCC is a power generation technology in which the Solid Feedstock is partially oxidized to produce syngas. In a modified IGCC design for carbon capture, there are several technological options which are evaluated in this paper. The first two options involve pre-combustion arrangements in which syngas is processed, either by shift conversion or chemical looping, to maximise the hydrogen level and to concentrate the carbon species as CO 2 . After CO 2 capture by gas–liquid absorption or chemical looping, the hydrogen-rich gas is used for power generation. The third capture option is based on post-combustion arrangement using chemical absorption. Investigated coal-based IGCC case studies produce 400–500 MW net power with more than 90% carbon capture rate. Principal focus of the paper is concentrated on evaluation of key performance indicators for investigated carbon capture options, the influence of various gasifiers on carbon capture process, optimisation of energy efficiency by heat and power integration, quality specification of captured CO 2 . The capture option with minimal energy penalty is based on chemical looping, followed by pre-combustion and post-combustion.
Gaofeng Quan - One of the best experts on this subject based on the ideXlab platform.
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Effect of Y Addition on the Semi-Solid Microstructure Evolution and the Coarsening Kinetics of SIMA AZ80 Magnesium Alloy
Metals, 2017Co-Authors: Qi Tang, Mingyang Zhou, Gaofeng QuanAbstract:Semi-Solid Feedstock of AZ80 magnesium alloy modified by trace rare-earth Y element (0, 0.2, 0.4, 0.8 wt. %) was fabricated by strain-induced melting activation (SIMA) in the form of extrusion and partial remelting. The effect of Y addition on the microstructure evolution of the extruded and isothermally heat treated alloy was observed by using an optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and quantitative analysis. The results show that the Y addition can refine the microstructure and make the β-Mg17Al12 phases agglomerate. During the subsequent isothermal treatment at 570 °C, the average Solid grain size, shape factor and liquid fractions increased with the prolonged soaking time. The smaller spheroidal Solid grains and larger shape factor were obtained in the semi-Solid microstructure due to Y addition. The coalescence and Ostwald ripening mechanism operated the coarsening process of Solid grains simultaneously. The coarsening rate constants of AZ80M1 (0.2 wt. % Y addition) of 164.22 μm3 s−1 was approximately four times less than the un-modified AZ80 alloy of 689.44 μm3 s−1. In contrast, the desirable semi-Solid structure featured, with fine and well globular Solid grains, an appropriate liquid fraction, and shape factor was achieved in AZ80M1 alloy treated at 570 °C for 20–30 min.
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Effect of Y Addition on the Semi-Solid Microstructure Evolution and the Coarsening Kinetics of SIMA AZ80 Magnesium Alloy
2017Co-Authors: Qi Tang, Mingyang Zhou, Gaofeng QuanAbstract:Semi-Solid Feedstock of AZ80 magnesium alloy modified by minor rare-earth Y element (0, 0.2, 0.4, 0.8 wt.%) were fabricated by strain induces melting activated (SIMA) in the form of extrusion and partial remelting. The effect of Y addition on the microstructure evolution of extruded and isothermal treated alloy was observed by optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and quantitative analysis. The results show that the Y addition can refine the microstructure and make the β-Mg17Al12 phases agglomerating. During the subsequent isothermal treatment at 570℃, the average Solid grain size, shape factor and liquid fractions increased with prolonged soaking time. Smaller spheroidal Solid grains and the larger shape factor were obtained due to Y addition. The coalescence and Ostwald ripening of Solid grains operated the coarsening process simultaneously. The coarsening rate constants of AZ80M1 (0.2 wt.% Y addition) of 164.22 μm3s-1 was approximately four times less than the un-modified AZ80 alloy of 689.44 μm3s-1. In contrast, the desirable semi-Solid structure featured by fine, well globular Solid grains and appropriate liquid fractions and shape factor was achieved in AZ80M1 alloy treated at 570℃ for 20-30 min.
Hyun Seok Cho - One of the best experts on this subject based on the ideXlab platform.
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Particle reactors for solar thermochemical processes
Solar Energy, 2017Co-Authors: Tatsuya Kodama, Nobuyuki Gokon, Selvan Bellan, Hyun Seok ChoAbstract:Utilization of solar thermal power for high temperature fuel production has the potential to significantly reduce the fossil fuel dependence of our current economy. Over the past two decades, remarkable progress has been made in the development of solar driven thermochemical reactors for the production of hydrogen and syngas as they are promising energy carriers for transportation, domestic and industrial applications. However, there are solar peculiarities in comparison to conventional thermochemical processes – high thermal flux density and frequent thermal transients because of the fluctuating insolation-, and conventional industrial thermochemical reactors are generally not suitable for solar driven reactors. Therefore, solar-specific modifications of reactor design are necessary to realize efficient solar driven thermochemical processes. In solar thermochemical reactors, the methods for solar-heating particulate Solid Feedstock to high temperatures can be broadly classified as solar “directly” and “indirectly” absorbing reactors. On solar thermochemical processes involving reacting Solid particles at high temperatures, such as “solar two-step water splitting with metal oxides” and “solar gasification” various types of solar directly and indirectly absorbing particle reactors have been developed. In this review, recent development of solar particle reactors for the above solar thermochemical processes is described.
Jurgen Karl - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen production from Solid Feedstock by using a nickel membrane reformer
Journal of Membrane Science, 2018Co-Authors: Jonas M. Leimert, Marius Dillig, Jurgen KarlAbstract:The Heatpipe Reformer technology allows the generation of hydrogen-rich, pressurized synthesis gas from Solid Feedstock like lignite or biomass. The resulting high hydrogen partial pressure and thus driving force makes it suitable for membrane separation. This work promotes the application of hydrogen permeable membranes as hydrogen separators directly in the reformer. This should allow a high hydrogen yield due the shift of the gasification reactions to the product side when hydrogen is removed continuously. The material of choice for this task is nickel as it combines good hydrogen permeability with good mechanical properties at the operation temperature of biomass gasification of 800 °C. The experimental section presents measurements with a bundle of nickel membranes used for the demonstration of the shift of different gas mixtures to the product side by hydrogen removal. Hydrogen removal enhanced CO and CH4 conversion at an operation temperature of 800 °C. A high purity of at least 99.9% was achieved by the highly selective solution-diffusion process of the separation. The experimental data was also used for an energy balance of the membrane process to allow a proper membrane layout in terms of membrane area per hydrogen production. As a last step, the membrane bundle was applied directly in the Heatpipe Reformer, an allothermal pressurized gasifier. It produced 200 mlmin−1 of hydrogen and showed no signs of degradation or fouling. This proof of concept showed the suitability of nickel membranes for hydrogen separation under gasification conditions.
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Conversion of Syngas from Biomass in Solid Oxide Fuel Cells
Journal of Fuel Cell Science and Technology, 2009Co-Authors: Jurgen Karl, Notka Frank, Sotiriοs Karellas, M. Saule, U. HohenwarterAbstract:Conversion of biomass in syngas by means of indirect gasification offers the option to improve the economic situation of any fuel cell system due to lower costs for Feedstock and higher power revenues in many European countries. The coupling of an indirect gasification of biomass and residues with highly efficient Solid oxide fuel cell (SOFC) systems is therefore a promising technology for reaching economic feasibility of small decentralized combined heat and power production (CHP).The predicted efficiency of common high temperature fuel cell systems with integrated gasification of Solid Feedstock is usually significantly lower than the efficiency of fuel cells operated with hydrogen or methane. Additional system components like the gasifier as well as the gas cleaning reduce this efficiency. Hence common fuel cell systems with integrated gasification of biomass will hardly reach electrical efficiencies above 30
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Conversion of Syngas From Biomass in Solid Oxide Fuel Cells
Journal of Fuel Cell Science and Technology, 2009Co-Authors: Jurgen Karl, Notka Frank, Sotiriοs Karellas, M. Saule, JOERN KARL, U. HohenwarterAbstract:Conversion of biomass in syngas by means of indirect gasification offers the option to improve the economic situation of any fuel cell system due to lower costs for Feedstock and higher power revenues in many European countries. The coupling of an indirect gasification of biomass and residues with highly efficient Solid oxide fuel cell (SOFC) systems is therefore a promising technology for reaching economic feasibility of small decentralized combined heat and power production (CHP).The predicted efficiency of common high temperature fuel cell systems with integrated gasification of Solid Feedstock is usually significantly lower than the efficiency of fuel cells operated with hydrogen or methane. Additional system components like the gasifier as well as the gas cleaning reduce this efficiency. Hence common fuel cell systems with integrated gasification of biomass will hardly reach electrical efficiencies above 30%. An extraordinary efficient combination is achieved in case that the fuel cells waste heat is used in an indirect gasification system. A simple combination of a SOFC and an allothermal gasifier enables then electrical efficiencies above 50%. However, this system requires an innovative cooling concept for the fuel cell stack. Another significant question is the influence of impurities on the fuel cell degradation. The European Research Project "BioCellus" focuses on both questions-the influence of the biogenous syngas on the fuel cells and an innovative cooling concept based on liquid metal heat pipes. First experiments showed that, in particular, higher hydrocarbons-the so-called tars-do not have any significant influence on the performance of SOFC membranes. The innovative concept of the TopCycle comprises to heat an indirect gasifier with the exhaust heat of the fuel cell by means of liquid metal heat-pipes. Internal cooling of the stack and the recirculation of waste heat increases the system efficiency significantly. This concept promises electrical efficiencies of above 50% even for small-scale systems without any combined processes.
Qi Tang - One of the best experts on this subject based on the ideXlab platform.
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Effect of Y Addition on the Semi-Solid Microstructure Evolution and the Coarsening Kinetics of SIMA AZ80 Magnesium Alloy
Metals, 2017Co-Authors: Qi Tang, Mingyang Zhou, Gaofeng QuanAbstract:Semi-Solid Feedstock of AZ80 magnesium alloy modified by trace rare-earth Y element (0, 0.2, 0.4, 0.8 wt. %) was fabricated by strain-induced melting activation (SIMA) in the form of extrusion and partial remelting. The effect of Y addition on the microstructure evolution of the extruded and isothermally heat treated alloy was observed by using an optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and quantitative analysis. The results show that the Y addition can refine the microstructure and make the β-Mg17Al12 phases agglomerate. During the subsequent isothermal treatment at 570 °C, the average Solid grain size, shape factor and liquid fractions increased with the prolonged soaking time. The smaller spheroidal Solid grains and larger shape factor were obtained in the semi-Solid microstructure due to Y addition. The coalescence and Ostwald ripening mechanism operated the coarsening process of Solid grains simultaneously. The coarsening rate constants of AZ80M1 (0.2 wt. % Y addition) of 164.22 μm3 s−1 was approximately four times less than the un-modified AZ80 alloy of 689.44 μm3 s−1. In contrast, the desirable semi-Solid structure featured, with fine and well globular Solid grains, an appropriate liquid fraction, and shape factor was achieved in AZ80M1 alloy treated at 570 °C for 20–30 min.
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Effect of Y Addition on the Semi-Solid Microstructure Evolution and the Coarsening Kinetics of SIMA AZ80 Magnesium Alloy
2017Co-Authors: Qi Tang, Mingyang Zhou, Gaofeng QuanAbstract:Semi-Solid Feedstock of AZ80 magnesium alloy modified by minor rare-earth Y element (0, 0.2, 0.4, 0.8 wt.%) were fabricated by strain induces melting activated (SIMA) in the form of extrusion and partial remelting. The effect of Y addition on the microstructure evolution of extruded and isothermal treated alloy was observed by optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and quantitative analysis. The results show that the Y addition can refine the microstructure and make the β-Mg17Al12 phases agglomerating. During the subsequent isothermal treatment at 570℃, the average Solid grain size, shape factor and liquid fractions increased with prolonged soaking time. Smaller spheroidal Solid grains and the larger shape factor were obtained due to Y addition. The coalescence and Ostwald ripening of Solid grains operated the coarsening process simultaneously. The coarsening rate constants of AZ80M1 (0.2 wt.% Y addition) of 164.22 μm3s-1 was approximately four times less than the un-modified AZ80 alloy of 689.44 μm3s-1. In contrast, the desirable semi-Solid structure featured by fine, well globular Solid grains and appropriate liquid fractions and shape factor was achieved in AZ80M1 alloy treated at 570℃ for 20-30 min.