The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Luis Puigjaner - One of the best experts on this subject based on the ideXlab platform.
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fluidized bed co Gasification of residual biomass poor coal blends for fuel gas production
Fuel, 2000Co-Authors: Enrique Velo, Xavier Roca, Joan J Manya, Luis PuigjanerAbstract:Abstract Experiments involving the co-Gasification of residual biomass/poor coal blends and Gasification of individual feedstocks used in the blends were performed in a bench scale, continuous fluidized-bed working at atmospheric pressure. Two types of blends were prepared, mixing pine chips (from Valcabadillo, Spain) with black coal, a low-grade coal from Escatron, Spain, and Sabero coal, a refuse coal from Sabero, Spain, in the ratio range of 0/100–100/0. Experimental tests were carried out using as a Gasification Agent mixtures of air and steam with dew points of 74–85°C at Gasification temperatures of 840–910°C and superficial fluidized gas velocities of 0.7–1.4 m/s. Feasibility studies were very positive, showing that blending effectively improved the performance of fluidized-bed co-Gasification of the low-grade coal, and the possibility of converting the refuse coal to a low-Btu fuel gas. This study indicates that a blend ratio with no less than 20% pine chips for the low-grade coal and 40% pine chips for the refuse coal are the most appropriate. The dry product gas low heating value augments with increasing blend ratio from 3700 to 4560 kJ/N m 3 for pine chips/low-grade coal, and from 4000 to 4750 kJ/N m 3 for pine chips/refuse coal. Dry product gas yield rises with the increase of the blend ratio from 1.80 to 3.20 N m 3 /kg (pine chips/low-grade coal), and from 0.75 to 1.75 N m 3 /kg (pine chips/refuse coal), respectively. About 50% co-Gasification process overall thermal efficiency can be achieved for the two types of blend.
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Fluidized-bed co-Gasification of residual biomass/poor coal blends for fuel gas production
Fuel, 2000Co-Authors: Enrique Velo, Xavier Roca, Joan J Manya, Luis PuigjanerAbstract:Abstract Experiments involving the co-Gasification of residual biomass/poor coal blends and Gasification of individual feedstocks used in the blends were performed in a bench scale, continuous fluidized-bed working at atmospheric pressure. Two types of blends were prepared, mixing pine chips (from Valcabadillo, Spain) with black coal, a low-grade coal from Escatron, Spain, and Sabero coal, a refuse coal from Sabero, Spain, in the ratio range of 0/100–100/0. Experimental tests were carried out using as a Gasification Agent mixtures of air and steam with dew points of 74–85°C at Gasification temperatures of 840–910°C and superficial fluidized gas velocities of 0.7–1.4 m/s. Feasibility studies were very positive, showing that blending effectively improved the performance of fluidized-bed co-Gasification of the low-grade coal, and the possibility of converting the refuse coal to a low-Btu fuel gas. This study indicates that a blend ratio with no less than 20% pine chips for the low-grade coal and 40% pine chips for the refuse coal are the most appropriate. The dry product gas low heating value augments with increasing blend ratio from 3700 to 4560 kJ/N m 3 for pine chips/low-grade coal, and from 4000 to 4750 kJ/N m 3 for pine chips/refuse coal. Dry product gas yield rises with the increase of the blend ratio from 1.80 to 3.20 N m 3 /kg (pine chips/low-grade coal), and from 0.75 to 1.75 N m 3 /kg (pine chips/refuse coal), respectively. About 50% co-Gasification process overall thermal efficiency can be achieved for the two types of blend.
Abel Rouboa - One of the best experts on this subject based on the ideXlab platform.
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parametric studies in the Gasification Agent and fluidization velocity during oxygen enriched Gasification of biomass in a pilot scale fluidized bed experimental and numerical assessment
Renewable Energy, 2020Co-Authors: Tamer M Ismail, Eliseu Monteiro, Abel Rouboa, Ana Ramos, Abd M ElsalamAbstract:Abstract The need to achieve renewable alternatives for energy production is pressing and new technologies have been developed. Biomass is a feasible feedstock for thermal conversion techniques like Gasification. This technique converts carbonaceous fuels into energy, producing a synthetic gas (syngas) with further commercial uses such as electricity generation, fuels or the chemical industry among others. In this work, a numerical model was developed in order to optimize the experimental parameters in the Gasification of agricultural residues. Hence, oxygen content (OC) in the gasifying Agent, equivalence ratio (ER) and fluidization velocity were varied so as to assess the effect of each parameter in syngas quality. Lower ER favored higher CO and H2 yields, enhancing also the lower heating value (LHV). Higher fluidization velocity also promoted these features, as well as Gasification conversion efficiency (GCE) and carbon conversion efficiency (CCE). Higher OC in the gasifying Agent improve syngas quality. The optimal Gasification performance was achieved for OC = 40%. The results obtained in this work are essential to describe scenarios relating to the potential use of agricultural residues as a source of energy via Gasification.
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Numerical investigation of optimum operating conditions for syngas and hydrogen production from biomass Gasification using Aspen Plus
Renewable Energy, 2020Co-Authors: Raquel Tavares, Eliseu Monteiro, Fouzi Tabet, Abel RouboaAbstract:Abstract This study is dedicated to present a reliable numerical methodology using Aspen Plus process simulator capable of performing a sensibility analysis of the downdraft Gasification of Portuguese forest residues. Effects of critical parameters, including Gasification temperature and steam-to-biomass ratio (SBR) on composition of the produced gas are discussed. The sensibility analysis is conducted using Aspen Plus simulator incorporating Fortran subroutines. The model is validated by experimental data and found to be in good agreement. The results of the sensibility analysis performed using air as Gasification Agent indicate that higher temperatures are favourable for a produced gas with higher hydrogen content and heating value. The simulation results also demonstrate that the use of steam as Gasification Agent allows increasing the hydrogen content and heating value of the produced gas in comparison to the use of air as gasifying Agent. The knowledge of this data is decisive to the development of projects concerning the use of Portuguese forest residues as energy source.
Enrique Velo - One of the best experts on this subject based on the ideXlab platform.
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fluidized bed co Gasification of residual biomass poor coal blends for fuel gas production
Fuel, 2000Co-Authors: Enrique Velo, Xavier Roca, Joan J Manya, Luis PuigjanerAbstract:Abstract Experiments involving the co-Gasification of residual biomass/poor coal blends and Gasification of individual feedstocks used in the blends were performed in a bench scale, continuous fluidized-bed working at atmospheric pressure. Two types of blends were prepared, mixing pine chips (from Valcabadillo, Spain) with black coal, a low-grade coal from Escatron, Spain, and Sabero coal, a refuse coal from Sabero, Spain, in the ratio range of 0/100–100/0. Experimental tests were carried out using as a Gasification Agent mixtures of air and steam with dew points of 74–85°C at Gasification temperatures of 840–910°C and superficial fluidized gas velocities of 0.7–1.4 m/s. Feasibility studies were very positive, showing that blending effectively improved the performance of fluidized-bed co-Gasification of the low-grade coal, and the possibility of converting the refuse coal to a low-Btu fuel gas. This study indicates that a blend ratio with no less than 20% pine chips for the low-grade coal and 40% pine chips for the refuse coal are the most appropriate. The dry product gas low heating value augments with increasing blend ratio from 3700 to 4560 kJ/N m 3 for pine chips/low-grade coal, and from 4000 to 4750 kJ/N m 3 for pine chips/refuse coal. Dry product gas yield rises with the increase of the blend ratio from 1.80 to 3.20 N m 3 /kg (pine chips/low-grade coal), and from 0.75 to 1.75 N m 3 /kg (pine chips/refuse coal), respectively. About 50% co-Gasification process overall thermal efficiency can be achieved for the two types of blend.
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Fluidized-bed co-Gasification of residual biomass/poor coal blends for fuel gas production
Fuel, 2000Co-Authors: Enrique Velo, Xavier Roca, Joan J Manya, Luis PuigjanerAbstract:Abstract Experiments involving the co-Gasification of residual biomass/poor coal blends and Gasification of individual feedstocks used in the blends were performed in a bench scale, continuous fluidized-bed working at atmospheric pressure. Two types of blends were prepared, mixing pine chips (from Valcabadillo, Spain) with black coal, a low-grade coal from Escatron, Spain, and Sabero coal, a refuse coal from Sabero, Spain, in the ratio range of 0/100–100/0. Experimental tests were carried out using as a Gasification Agent mixtures of air and steam with dew points of 74–85°C at Gasification temperatures of 840–910°C and superficial fluidized gas velocities of 0.7–1.4 m/s. Feasibility studies were very positive, showing that blending effectively improved the performance of fluidized-bed co-Gasification of the low-grade coal, and the possibility of converting the refuse coal to a low-Btu fuel gas. This study indicates that a blend ratio with no less than 20% pine chips for the low-grade coal and 40% pine chips for the refuse coal are the most appropriate. The dry product gas low heating value augments with increasing blend ratio from 3700 to 4560 kJ/N m 3 for pine chips/low-grade coal, and from 4000 to 4750 kJ/N m 3 for pine chips/refuse coal. Dry product gas yield rises with the increase of the blend ratio from 1.80 to 3.20 N m 3 /kg (pine chips/low-grade coal), and from 0.75 to 1.75 N m 3 /kg (pine chips/refuse coal), respectively. About 50% co-Gasification process overall thermal efficiency can be achieved for the two types of blend.
Hermann Hofbauer - One of the best experts on this subject based on the ideXlab platform.
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Tar content and composition during a low-temperature steam Gasification of rice husks
Chemical Papers, 2019Co-Authors: Van Minh Duong, Monika Seiber, Hermann HofbauerAbstract:The research work extends our recent empirical knowledge on the rice husks, a carbonaceous solid material. This solid biofuel option was characterized with a potential net heating value of 16–17 MJ/kg, significant high ash deformation temperature recorded above 1450 °C, capable and considerable for thermochemical conversion systems. An experimental performance on a dual fluidized bed steam gasifier using rice husks pellets was carried out at a low temperature between 600 and 650 °C and fuel power of 100 kW_th. Pure steam was used as a Gasification Agent in fluidization at a steam to fuel ratio of 1.2 kg/kg on dry basis. Calcite with mainly CaCO_3 in composition was used as bed material for the reactor. Tar content and composition in the product gas stream were analyzed with a gas chromatograph coupled with mass spectrometer (GC–MS). Significant high amounts of total GC–MS tar components (without benzene, ethylbenzene, and xylene) and gravimetric tar (higher molecular tar) were detected at 29.44 and 17.82 g/m^3 on dry basis. Benzene content was, respectively, presented on a value of 9 g/m^3 on dry basis. Obtained products consisted of relevant amount of phenol and heterocyclic aromatic tars (class 2). The specific composition of common and additional analytes presented in GS–MS tar was summarized for better understanding of tar formation and reduction phenomena of rice husk Gasification.
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CO2 Gasification in a dual fluidized bed reactor system: Impact on the product gas composition
Fuel, 2019Co-Authors: Anna Magdalena Mauerhofer, Josef Fuchs, Stefan Müller, Florian Benedikt, J.c. Schmid, Hermann HofbauerAbstract:Abstract The use of CO 2 as Gasification Agent in the 100 kW th dual fluidized bed Gasification pilot plant was investigated at TU Wien. For this purpose, steam was replaced stepwise by CO 2 as Gasification Agent. Softwood was used as fuel and olivine as bed material. Starting from 100 vol.-% steam as Gasification Agent, substituting it by 32, 45 and finally 68 vol.-% CO 2 . All loop seals were fluidized further with steam, which resulted in these volume percentages. Additionally, a CO 2 Gasification test campaign converting softwood with a mixture (90/10 wt.-%) of olivine and limestone was investigated. For this case, the Gasification Agent was composed of 65 vol.-% CO 2 and 35 vol.-% steam. The use of CO 2 as Gasification Agent led to changes of the product gas. Instead of a H 2 -enriched product gas, which was produced during steam Gasification, CO and CO 2 occupied the major share of the product gas. Consequently, the H 2 /CO ratios as well as the lower heating values decreased when substituting steam by CO 2 . Tar contents were lower for CO 2 /steam Gasification compared to pure steam Gasification.
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CO_2 Gasification of biogenic fuels in a dual fluidized bed reactor system
Biomass Conversion and Biorefinery, 2019Co-Authors: Anna Magdalena Mauerhofer, Josef Fuchs, Stefan Müller, Florian Benedikt, Alexander Bartik, Hermann HofbauerAbstract:A 100 kW_th dual fluidized bed steam Gasification pilot plant has been developed at TU Wien to convert different types of biogenic fuels into a valuable product gas. In this paper, the conversion of different biogenic fuels in combination with the utilization of CO_2 as alternative Gasification Agent was investigated in the mentioned pilot plant. For this purpose, five experimental campaigns were carried out aiming at the investigation of softwood as reference fuel, and rapeseed cake, bark and lignin as alternative fuels. Pure olivine as well as a mixture (90/10 wt%) of olivine and limestone were used as bed materials. The product gas compositions of the different biogenic fuels changed depending on the elemental composition of the biogenic fuels. Thus, a high amount of carbon in the fuel enhanced CO formation, whereas an increased content of oxygen led to higher CO_2 contents. Additionally, the presence of alkali metals in the biomass ash favoured the production of CO. The addition of limestone enhanced the H_2 and CO contents via the water gas shift reaction as well as steam and dry reforming reactions, but had no significant effect on tar contents. Overall, this paper presents the feasibility of the dual-fluidized bed Gasification process of different biogenic fuels with CO_2 as Gasification Agent.
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Biomass Gasification for Synthesis Gas Production and Applications of the Syngas
Advances in Bioenergy: The Sustainability Challenge, 2015Co-Authors: R. Rauch, Jitka Hrbek, Hermann HofbauerAbstract:Synthesis gas from biomass can be produced and utilized in different ways. Conversion of biomass to synthesis gas can be done either in fluidized bed or entrained flow reactors. As Gasification Agent oxygen, steam, or mixtures are used. The most common use of biomass Gasification in the last decades has been for heat and/or power production. Nowadays, the importance of transportation fuels from renewables is increased due to environmental aspects and growing fossil fuels prices. That is why the production of Fischer-Tropsch (FT) liquids, methanol, mixed alcohols, substitute natural gas (SNG), and hydrogen from biomass is now in focus of view. The most innovative and interesting ways of synthesis gas utilization and projects, BioTfueL or GoBiGas, BioLiq, Choren, etc. are discussed here. Further the microchannel technology by Oxford Catalysts and distributed production of SNG in decentral small scale are presented. The synthesis platform in Guessing, Austria is also presented. The FT liquids, hydrogen production, mixed alcohols, and BioSNG, these are the projects associated with the FICFB Gasification plant in Guessing. Also the principle and examples of sorption-enhanced reforming to adjust H2/CO ratio in product gas during the Gasification is described. Finally, in the conclusion also an outlook for the thermochemical pathway to transportation fuels is given. WIREs Energy Environ 2014, 3:343-362. doi: 10.1002/wene.97 For further resources related to this article, please visit the WIREs website.
Sebastian Werle - One of the best experts on this subject based on the ideXlab platform.
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Sewage sludge Gasification process for clean and sustainable environment
Renewable Energy and Environmental Sustainability, 2020Co-Authors: Sebastian WerleAbstract:This work presents a multicriterial investigation of the sewage sludge Gasification in the fixed bed gasifier. The operating parameters of Gasification were varied over a wide range. Parameters such as air ratio λ = 0.12–0.27, Gasification Agent preheating t = 50–250 °C and Gasification Agent composition (z O2 = 0.21 and z O2 > 0.21) were found to influence syngas lower heating value and syngas composition.
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Gasification of a Dried Sewage Sludge in a Laboratory Scale Fixed Bed Reactor
Energy Procedia, 2020Co-Authors: Sebastian WerleAbstract:The paper present study on the air Gasification process of dried sewage sludge. Parameters such as air ratio λ=0.12÷0.27, air temperature t=50oC÷250oC and molar fraction of O2 in Gasification Agent zO2=0.21 and zO2>0.2) were found to influence on the syngas parameters: Lower Heating Value (LHV) and composition. The results indicate that the syngas LHV was found to decrease with increase air ratio for all analyzed cases. Increasing O2 concentration in Gasification Agent increased the temperature, which tended to favour the formation of smaller molecular components in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional Gasification, a process with a preheated Gasification Agent causes that the flux of heat necessary to support endothermic Gasification reactions is producing more effective. As a result, H2 and CO production is promoted.
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Gasification of a Dried Sewage Sludge in a Laboratory Scale Fixed Bed Reactor
Energies, 2015Co-Authors: Sebastian WerleAbstract:This paper presents an investigation of sewage sludge Gasification in a fixed bed gasifier. Experiments were conducted on a laboratory scale fixed bed gasifier. In the experiments, two types of dried sewage sludge were tested and their properties were analysed. Parameters such as air ratio λ = 0.12 to 0.27, Gasification Agent temperature t = 50 to 250 °C and Gasification Agent composition ( = 0.21 and > 0.21) were found to influence on temperature distribution, syngas Lower Heating Value (LHV) and syngas composition. The results indicate that the syngas LHV was found to decrease with increased air ratio for all analyzed cases: cold and preheated air and cold enriched air. The increase in the percentage of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Increasing oxygen concentration increased the temperature, which tended to favor the formation of smaller molecules in the gas mixture. Thus, the enriched air medium produced a gas with a higher LHV. In contrast to conventional Gasification, Gasification process with Gasification Agent preheating causes that the flux of heat necessary to support endothermic Gasification reactions is producing more effective. Air preheating causes increases hydrogen and carbon monoxide production.