The Experts below are selected from a list of 459 Experts worldwide ranked by ideXlab platform
Shusheng Pang - One of the best experts on this subject based on the ideXlab platform.
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co gasification of cassava rhizome and woody biomass in the 1 mw _ el prototype dual Fluidised Bed Gasifier by gussing renewable energy
IOP Conference Series: Earth and Environmental Science, 2020Co-Authors: J Hongrapipat, Shusheng Pang, V Siriwongrungson, M Messner, C Henrich, S Gunnarsson, M Koch, M Dichand, R Rauch, H HofbauerAbstract:In the current research, the effect of the mixture ratio by weight of wood chips to cassava rhizome (100%:0%, 75%:25%, and 50%:50%) was investigated on the properties of the product gas produced from the Dual Fluidised Bed Gasifier power plant. The DFB Gasifier power plant is located in Nongbua district, Nakhon Sawan province, Thailand. The results from this study show that the use of 100% wood chips as a fuel generates high quality product gas as designed. The mixture of wood chips and cassava rhizome in the weight ratio of 75%:25% and 50%:50% also gives satisfactory results: steady operation conditions of the whole power plant process, good quality and quantity of product gas, however, the tar content in the product gas was slightly higher than that of using wood chips alone. The researchers found that cassava rhizome can be used as a fuel mixture together with wood chips in the current DFB Gasifier at site to generate heat and electricity. The outcome of this research will create the use of waste cassava rhizome, enormously available around the power plant, as well as the broad application of gasification technology using various biomass feedstock types available in Thailand.
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Experimental investigation of tar formation and producer gas composition in biomass steam gasification in a 100 kW dual Fluidised Bed Gasifier
Renewable Energy, 2019Co-Authors: Ziyin Zhang, Shusheng PangAbstract:Abstract In this study, three types of biomass including corn stover, radiata pine wood and rice husk in the form of pellets were gasified with steam as gasification agent in a 100 kW dual Fluidised Bed Gasifier. Tar formation in initial devolatilization stage and its correlation to the final tar concentration in the producer gas were investigated. In addition, the yields and composition of the producer gas for each type of biomass were also examined. In the gasification experiments, operating temperature was controlled, respectively, at 700 °C and 800 °C. Silica sand was used as the Bed material with an inventory of 30 kg. For simulation of the initial devolatilization stage in the steam gasification, N2 was used as fluidization agent. From this study, it is found that there was a positive correlation between tar contents in the devolatilization product gas and those in the final producer gas from gasification. In the devolatilization stage, radiata pine biomass yielded more phenols, while corn stover generated more toluene. Based on the results of this study, tar formation mechanism was proposed which is verified by the observation that more naphthalene was present in the producer gas from gasification of radiata pine while gasification of corn stover produced more biphenyl. The experimental results also show that at gasification temperature of 700 °C, the producer gas yield was the highest for corn stover followed by rice husk and then radiata pine wood. However, for gasification at 800 °C, the trend was reversed with radiata pine having the highest yield followed by risk husk and the corn stover. At both 700 and 800 °C, the radiata pine biomass produced a producer gas with higher contents of H2 and CH4 while the producer gas from rice husk had a higher content of CO and that from corn stover had a higher content of CO2, C2H4 and C2H6. These differences are closely related to the chemical composition of the biomass which was also analysed in this study. Radiata pine had a higher content of lignin (31.96 wt%), rice husk had a higher content of hemicellulose (25.30 wt%) while corn stover was rich in cellulose (69.85 wt%).
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from aromatic tars to light hydrocarbon gas species during biomass steam gasification in a 100kw dual Fluidised Bed Gasifier
Chemeca 2018, 2018Co-Authors: Ziyin Zhang, Shusheng PangAbstract:In biomass gasification, gas cleaning to remove and convert tar compounds is one of the main challenges for the successful commercialisation of biomass gasification. In order to understand tar formation mechanism during the gasification process, and estimate the tar yield under different operating conditions, this study has investigated tar yield and composition both from initial devolatilization stage and final the subsequent gasification stage. Experiments were conducted on a 100kW dual Fluidised Bed (DFB) Gasifier over the temperature range of 700-800degreesC with a residence time of 1.9 -2.5 s. Tar components were quantified by gas chromatography with a flame ionisation detector (GC-FID) analysis. The experimental results showed that a close correlation between the aromatic tar components formed in the initial devolatilization stage and the concentration changes in light hydrocarbon gases (CH4, C2H4 and C2H6) in the producer gas. The forms of these relations vary with the gas species and are affected by operating conditions of gasification, types of Gasifier and biomass composition. These results will help understand the tar conversion and transformation process during the biomass steam gasification and optimise the gasification process for low tar concentration in the producer gas.
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experimental investigation of biomass devolatilization in steam gasification in a dual Fluidised Bed Gasifier
Fuel, 2017Co-Authors: Ziyin Zhang, Shusheng PangAbstract:Abstract In this study, biomass devolatilization, which is the initial stage of steam gasification, was experimentally investigated in a 100 kW dual Fluidised Bed Gasifier. In the experiments, pellets of radiata pine sawdust were used as the feedstock, and silica sand was used as the Bed material. The operating temperature in the Gasifier was varied from 700 to 800 °C and N 2 was used as the fluidisation agent. Once the devolitilization test was completed, corresponding gasification experiment was conducted at the same operation condition but N 2 was switched to steam as gasification and fluidisation agent. From the experimental results, it is found that, in the devolatilization stage, gas yield was increased, and tar yield and concentration were decreased with increase in operation temperature. In this study, significant correlation was observed for gas yield and gas composition between the devolatilization stage and the gasification stage. Correlations on tar concentrations and yield were also clear for gases produced from the devolatilization and gases from the subsequent gasification. This study provides fundamental information for understanding and optimization of the biomass steam gasification.
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Effect of steam to biomass ratio and calcite Bed material on the performance of a 100kwth dual Fluidised Bed Gasifier
2012Co-Authors: Woei Lean Saw, Janjira Hongrapipat, Shusheng PangAbstract:In this study, a series of experiments has been conducted in a 100kWth dual Fluidised Bed Gasifier to investigate the influence of steam to biomass (S/B) ratio and calcite loading in the Bed material on gas composition, H2/CO and H2/CO2 ratios, NH3, H2S and tar content of the producer gas. In the experiments, wood pellets of radiata pine sawdust were used as the feedstock. The gasification temperature was set at 710-750 degreesC while the combustion temperature was maintained at 825 degreesC. The S/B ratio of the gasification process was varied from 0.67 to 1.0 kg/kgdry at each calcite loading of 0%, 50% and 100%. The results of this study showed that the performance of the DFB steam Gasifier increased with the calcite loading. The H2/CO ratio increased from 0.7 to 3.4 by increasing the calcite loading from 0% to 100%. In addition, the 100% calcite loading also has a catalytic effect on reducing the concentrations of CH4 and light hydrocarbons (LH) by 14% and 46%, respectively, compared with 0% calcite loading. Furthermore, the total tar concentration decreased significantly from 4.7 to 0.7 g/Nm3 with the increase in calcite loading from 0 to 100%. With 100% calcite loading, the H2/CO was further increased from 3.4 to 4.3 with the increase in the S/B ratio. However, the influence of S/B ratio was insignificant on CH4, LH, NH3, H2S and Tar.
Wennan Zhang - One of the best experts on this subject based on the ideXlab platform.
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Internal tar/CH_4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH_4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH_4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH_4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H_2 content together with lower CH_4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m^3 and the CH_4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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internal tar ch4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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an experimental study on catalytic Bed materials in a biomass dual Fluidised Bed Gasifier
Renewable Energy, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Per Engstrand, Wennan ZhangAbstract:Abstract A study on in-Bed material catalytic reforming of tar/CH 4 has been performed in the 150 kW allothermal Gasifier at Mid Sweden University (MIUN). The major challenge in biomass Fluidised-Bed gasification to produce high-quality syngas, is the reforming of tars and CH 4 . The MIUN Gasifier has a unique design suitable for in-Bed tar/CH 4 catalytic reforming and continuously internal regeneration of the reactive Bed material. This paper evaluates the catalytic effects of olivine and Fe-impregnated olivine (10%wtFe/olivine Catalyst) with reference to silica sand in the MIUN dual Fluidised Bed (DFB) Gasifier. Furthermore, a comparative experimental test is carried out with the same operation condition and Bed-materials when the Gasifier is operated in the mode of single bubbling Fluidised Bed (BFB), in order to detect the internal regeneration of the catalytic Bed materials in the DFB operation. The behaviour of catalytic and non-catalytic Bed materials differs when they are used in the DFB and the BFB. Fe/olivine and olivine in the BFB mode give lower tar and CH 4 content together with higher H 2 + CO concentration, and higher H 2 /CO ratio, compared to DFB mode. It is hard to show a clear advantage of Fe/olivine over olivine regarding tar/CH 4 catalytic reforming.
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Internal tar/CH4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2014Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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internal tar ch4 reforming using a novel design in a biomass dual Fluidised Bed Gasifier
European Biomass Conference and Exhibition Proceedings, 2013Co-Authors: Kristina Goransson, Ulf Soderlind, Wennan ZhangAbstract:Reforming of tars and methane (CH4) in syngas is a significant challenge for low-temperature biomass gasification. For a dual Fluidised Bed Gasifier (DFBG), catalytic Bed materials are usually used to promote the reforming reactions. Intensive contact between gas and catalytic Bed material at high temperature enhances the internal tar/CH4 reforming. The MIUN Gasifier, built for research into synthetic fuel production, is a dual Fluidised Bed Gasifier (DFBG). The results with different Bed materials (silica sand, olivine and Fe-impregnated olivine) give roughly equivalent amounts of methane and gravimetric tar in the raw untreated syngas, and need to be reduced to an acceptably low level. The gasification research group at MIUN investigates a novel design in the MIUN Gasifier, to increase the gasification efficiency, suppress the tar generation and to upgrade the syngas quality. The first step is taken towards a novel design in the MIUN Gasifier. The application is expected to significantly enhance the syngas quality.
Kristina Goransson - One of the best experts on this subject based on the ideXlab platform.
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Internal tar/CH_4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH_4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH_4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH_4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H_2 content together with lower CH_4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m^3 and the CH_4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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internal tar ch4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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an experimental study on catalytic Bed materials in a biomass dual Fluidised Bed Gasifier
Renewable Energy, 2015Co-Authors: Kristina Goransson, Ulf Soderlind, Per Engstrand, Wennan ZhangAbstract:Abstract A study on in-Bed material catalytic reforming of tar/CH 4 has been performed in the 150 kW allothermal Gasifier at Mid Sweden University (MIUN). The major challenge in biomass Fluidised-Bed gasification to produce high-quality syngas, is the reforming of tars and CH 4 . The MIUN Gasifier has a unique design suitable for in-Bed tar/CH 4 catalytic reforming and continuously internal regeneration of the reactive Bed material. This paper evaluates the catalytic effects of olivine and Fe-impregnated olivine (10%wtFe/olivine Catalyst) with reference to silica sand in the MIUN dual Fluidised Bed (DFB) Gasifier. Furthermore, a comparative experimental test is carried out with the same operation condition and Bed-materials when the Gasifier is operated in the mode of single bubbling Fluidised Bed (BFB), in order to detect the internal regeneration of the catalytic Bed materials in the DFB operation. The behaviour of catalytic and non-catalytic Bed materials differs when they are used in the DFB and the BFB. Fe/olivine and olivine in the BFB mode give lower tar and CH 4 content together with higher H 2 + CO concentration, and higher H 2 /CO ratio, compared to DFB mode. It is hard to show a clear advantage of Fe/olivine over olivine regarding tar/CH 4 catalytic reforming.
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Internal tar/CH4 reforming in a biomass dual Fluidised Bed Gasifier
Biomass Conversion and Biorefinery, 2014Co-Authors: Kristina Goransson, Ulf Soderlind, Till Henschel, Per Engstrand, Wennan ZhangAbstract:An internal reformer is developed for in situ catalytic reforming of tar and methane (CH4) in allothermal Gasifiers. The study has been performed in the 150 kW dual Fluidised Bed (DFB) biomass Gasifier at Mid Sweden University (MIUN). The MIUN Gasifier is built for research on synthetic fuel production. Reduction of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass Fluidised-Bed gasification technology towards automotive fuel production. The MIUN Gasifier has a unique design with an internal reformer, where intensive contact of gas and catalytic solids improves the reforming reactions. This paper presents an initial study on the internal reformer operated with and without Ni-catalytic pellets, by evaluation of the syngas composition and tar/CH4 content. A novel application of Ni-catalyst in DFB Gasifiers is proposed and studied in this work. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases down to 5 g/m3 and the CH4 content down below 6 % in the syngas. The tar content can be decreased further to lower levels, with increased gas contact to the specific surface area of the catalyst and increased catalyst surface-to-volume ratio. The new design in the MIUN Gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas quality.
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internal tar ch4 reforming using a novel design in a biomass dual Fluidised Bed Gasifier
European Biomass Conference and Exhibition Proceedings, 2013Co-Authors: Kristina Goransson, Ulf Soderlind, Wennan ZhangAbstract:Reforming of tars and methane (CH4) in syngas is a significant challenge for low-temperature biomass gasification. For a dual Fluidised Bed Gasifier (DFBG), catalytic Bed materials are usually used to promote the reforming reactions. Intensive contact between gas and catalytic Bed material at high temperature enhances the internal tar/CH4 reforming. The MIUN Gasifier, built for research into synthetic fuel production, is a dual Fluidised Bed Gasifier (DFBG). The results with different Bed materials (silica sand, olivine and Fe-impregnated olivine) give roughly equivalent amounts of methane and gravimetric tar in the raw untreated syngas, and need to be reduced to an acceptably low level. The gasification research group at MIUN investigates a novel design in the MIUN Gasifier, to increase the gasification efficiency, suppress the tar generation and to upgrade the syngas quality. The first step is taken towards a novel design in the MIUN Gasifier. The application is expected to significantly enhance the syngas quality.
Dongke Zhang - One of the best experts on this subject based on the ideXlab platform.
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Bubble dynamics and its effect on the performance of a jet Fluidised Bed Gasifier simulated using CFD
Fuel, 2006Co-Authors: Kun Gao, Yang Wang, Dongke ZhangAbstract:Abstract A computational fluid dynamic modelling study of a jet Fluidised Bed Gasifier has been carried out. The modelling was based on the Eulerian–Eulerian models for gas and solid flows, which take into account the hydrodynamics, mass and heat transfer, and heterogeneous and homogeneous reactions. The bubble dynamics was simulated in detail, enabling its effect on temperature distributions, gasification reactions and gas compositions in the Bed to be examined. The results revealed that jet growth, bubble rise, and the associated convective flow play a significant role in the heat exchange and mass transfer, and in turn, affect the gasification reactions.
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Modelling of a laboratory-scale bubbling Fluidised-Bed Gasifier with feeds of both char and propane
Fuel, 2004Co-Authors: Davide Ross, Hongming Yan, Dongke ZhangAbstract:Abstract A previous mathematical model developed for a bubbling Fluidised-Bed coal Gasifier was modified for simulating the performance of a laboratory-scale Gasifier with feeds of both Yallourn char and propane by incorporating propane decomposition and combustion reactions and reaction kinetics. Model predictions of the in-Bed axial gas concentration profiles for O2, CO, CO2, CH4, and C3H8 compared well, except for the minor gas species of both C2H4 and C3H6, to the experimental data at operating Bed temperatures of 850 and 950 °C, respectively. In contrast, the predicted gas species show a poor agreement with the experimental data, particularly for the carbon oxide species at 750 °C. Most importantly, the addition of propane to simulate the volatile matter released from coal devolatilisation process results in an increase in the proportion of oxygen consumed by homogeneous combustion. This leads to an increase in an availability of char for char gasification reactions, subsequently showing an increase in carbon conversion due to gasification over the sole gasification of char. The specific energy of the syngas gas has been shown to increase due to the enhancement of the char gasification reactions in the presence of volatiles. This further demonstrates the importance of incorporating homogenous combustion into the model for correctly predicting the Gasifier performance, particularly for the in-Bed feeding of coal with high volatile content.
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mathematical modelling of a bubbling Fluidised Bed coal Gasifier and the significance of net flow
Fuel, 1998Co-Authors: Dongke Zhang, Hongming Yan, Craig HeidenreichAbstract:Abstract An isothermal model, incorporating the two-phase theory, has been developed to evaluate the performance of a bubbling Fluidised-Bed coal Gasifier. A distinctive feature of this model is the consideration of a net flow term from the emulsion phase to the bubble phase in the conservation equations. Simulations with consideration of the net flow term indicate that the overall results compare favourably with available experimental data from an industrial Fluidised-Bed Gasifier reported in the literature. The net flow is significant, in the range 71–87% relative to the feed gas rate, strongly depending on the coal rank, heterogeneous reaction rates and volatile matter released in the Bed. The higher the coal rank, the lower the net flow and total excess gas flow. The large volume of net flow generated can significantly change the fluidisation conditions in the Bed and thus alter the reaction rates and mass transfer properties. Simulations without the net flow deviate significantly from the experimental results.
Juan Manuel De Andrés - One of the best experts on this subject based on the ideXlab platform.
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Modeling and model performance evaluation of sewage sludge gasification in fluidized-Bed Gasifiers using Aspen Plus.
Journal of the Air & Waste Management Association (1995), 2018Co-Authors: Juan Manuel De Andrés, Michel Vedrenne, Matteo Brambilla, Encarnación RodríguezAbstract:A model was developed to simulate the sewage sludge gasification in an atmospheric Fluidised Bed Gasifier using Aspen Plus. The model here presented was based on the Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it against previously published experimental data obtained in a lab-scale gasification plant. A sensitivity analysis of the model was carried out by modifying parameters such as the temperature, equivalence ratio (ER) and the steam-to-biomass ratio. The modeled results were in good agreement with the experimental data (especially when air was used as gasifying agent) and reproduced satisfactorily the experimental trends found for the gas composition, the carbon conversion (Xc) and the cold gas efficiency (CGE) under different gasification conditions. Operating at higher temperatures increased the production of H2 and CO, as well as the Xc and the CGE. The increase in ER produced higher Xc, yet the CGE experienced slight changes due to a decrease in the lower heating value of the resulting syngas, as well as the oxidation of combustible gases. The use of air+steam as gasifying agent increased the H2 content of the produced gases but decreased the accuracy of the model.
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Modeling and model performance evaluation of sewage sludge gasification in fluidized-Bed Gasifiers using Aspen Plus
2018Co-Authors: Juan Manuel De Andrés, Michel Vedrenne, Matteo Brambilla, Encarnación RodríguezAbstract:A model was developed to simulate the sewage sludge gasification in an atmospheric Fluidised Bed Gasifier using Aspen Plus. The model here presented was based on the Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it against previously published experimental data obtained in a lab-scale gasification plant. A sensitivity analysis of the model was carried out by modifying parameters such as the temperature, equivalence ratio (ER) and the steam-to-biomass ratio. The modeled results were in good agreement with the experimental data (especially when air was used as gasifying agent) and reproduced satisfactorily the experimental trends found for the gas composition, the carbon conversion (Xc) and the cold gas efficiency (CGE) under different gasification conditions. Operating at higher temperatures increased the production of H2 and CO, as well as the Xc and the CGE. The increase in ER produced higher Xc, yet the CGE experienced slight changes due to a decrease in the lower heating value of the resulting syngas, as well as the oxidation of combustible gases. The use of air+steam as gasifying agent increased the H2 content of the produced gases but decreased the accuracy of the model. Implications: Gasification is an available alternative to produce energy as well as several raw materials from sewage sludge. The syngas obtained from this technology totally depends on the type of Gasifier and the operation conditions, which can be optimized with the help of models. In this work, a relatively simple model was built using ASPEN PLUS. Despite its simplicity, the outputs of the model are in good agreement with experimental results what makes its use interesting for assessing scaling-up possibilities from lab-scale to pilot-scale gasification processes.
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Air-steam gasification of sewage sludge in a bubbling Bed reactor: Effect of alumina as a primary catalyst
Fuel Processing Technology, 2011Co-Authors: Juan Manuel De Andrés, Adolfo Narros, María Encarnación RodríguezAbstract:Abstract Numerous references can be found in scientific literature regarding biomass gasification. However, there are few works related to sludge gasification. A study of sewage sludge gasification process in a bubbling Fluidised Bed Gasifier on a laboratory scale is here reported. The aim was to find the optimum conditions for reducing the production of tars and gain more information on the influx of different operating variables in the products resulting from the gasification of this waste. The variables studied were the equivalence ratio (ER), the steam-biomass ratio (SB) and temperature. Specifically, the ER was varied from 0.2 to 0.4, the SB from 0 to 1 and the temperature from 750 °C (1023 K) to 850 °C (1123 K). Although it was observed that tar production could be considerably reduced (up to 72%) by optimising the gasification conditions, the effect of using alumina (aluminium oxide, of proven efficacy in destroying the tar produced in biomass gasification) as primary catalyst in air and air-steam mixture tests was also verified. The results show that by adding small quantities of alumina to the Bed (10% by weight of fed sludge) considerable reductions in tar production can be obtained (up to 42%) improving, at the same time, the lower heating value (LHV) of the gas and carbon conversion.