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Martin Olazar - One of the best experts on this subject based on the ideXlab platform.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Energy, 2022Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:Abstract The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence of temperature on the product yields has been analyzed in the 500–800 °C range. A detailed analysis of the volatile stream (condensable and non-condensable components) has been carried out by chromatographic techniques, and the char samples have been characterized by ultimate and proximate analyses, N2 adsorption-desorption, and Scanning Electron Microscopy. A high bio-oil yield was obtained at 500 °C (75.4 wt%), which is evidence of the suitable features of the conical Spouted Bed Reactor for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600 °C), and only had a little influence at 700 °C due to the low gas residence time in the conical Spouted Bed Reactor. At 800 °C, the reaction mechanism was controlled by gasification reactions. The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. Thus, phenolic compounds accounted for the major fraction at low pyrolysis temperatures, whereas hydrocarbons prevailed at 800 °C. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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conversion of hdpe into value products by fast pyrolysis using fcc spent catalysts in a fountain confined conical Spouted Bed Reactor
Chemsuschem, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Mayra Suarez, Martin OlazarAbstract:Continuous catalytic cracking of polyethylene over a spent fluid catalytic cracking (FCC) catalyst was studied in a conical Spouted Bed Reactor (CSBR) with fountain confiner and draft tube. The effect of temperature (475-600 °C) and space-time (7-45 gcat min gHDPE-1 ) on product distribution was analyzed. The CSBR allows operating with continuous plastic feed without defluidization problems and is especially suitable for catalytic pyrolysis with high catalyst efficiency. Thus, high catalyst activity was observed, with waxes yield being negligible above 550 °C. The main product fraction obtained in the catalytic cracking was made up of C5 -C11 hydrocarbons, with olefins being the main components. However, its yield decreased as temperature and residence time were increased, which was due to reactions involving cracking, hydrogen transfer, cyclization, and aromatization, leading to light hydrocarbons, paraffins, and aromatics. The proposed strategy is of great environmental relevance, as plastics are recycled using an industrial waste (spent FCC catalyst).
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pyrolysis of plastic wastes in a fountain confined conical Spouted Bed Reactor determination of stable operating conditions
Energy Conversion and Management, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Jon Alvarez, Martin OlazarAbstract:Abstract The performance of both fluidized and Spouted Bed Reactors in the pyrolysis of waste plastics is conditioned by particle agglomeration phenomena, which worsens the quality of the gas–solid contact and eventually lead to defluidization. The objective of this work is to determine the optimum conditions for stable operation (without defluidization) in a bench scale plant fitted with a fountain confined conical Spouted Bed Reactor and equipped with a nonporous draft tube, which operates in continuous mode. The insertion of these devices enhances the gas–solid contact, especially in the fountain region, and leads to a highly stable hydrodynamic regime, with these features being of especial relevance for the in situ catalytic pyrolysis of waste plastics. This paper deals with the effect different variables have on the minimum temperature for stable operation by avoiding defluidization. The variables analyzed are as follows: plastic type (HDPE, LDPE, PP, PS, PET and PMMA), plastic feed rate, mass of inert material in the Bed, spouting velocity and use of catalyst. The results show that polymers whose chains decompose at low temperatures or have high degrees of branching require low operating temperatures. Besides, as the ratio of Bed mass to plastic feed rate (WBed/Qplastic) and/or spouting velocity were increased, the temperature required to avoid defluidization was also reduced. The use of a catalyst also reduced the temperature required for stable operation, as the activation energy of cracking reactions is greatly reduced, and so reaction rate is increased.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Social Science Research Network, 2021Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence temperature in the 500-800 oC range has on the product yields has been analysed. A detailed analysis of the gaseous streamhas been carried out by chromatographic techniques, and the char samples have been characterized by several techniques.A high bio-oil yield was obtained at 500 oC (75.4 wt.%), which is evidence of the suitable features of the CSBR for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600oC), and only had a little influence at 700oC due to the low gas residence time in the CSBR. At 800 oC, the reaction mechanism was controlled by gasification reactions.The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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on the pyrolysis of different microalgae species in a conical Spouted Bed Reactor bio fuel yields and characterization
Bioresource Technology, 2020Co-Authors: Kolsoom Azizi, G. Lopez, Maider Amutio, Aitor Arregi, Mostafa Keshavarz Moraveji, Martin OlazarAbstract:Abstract The aim of this work was to study fast pyrolysis of three microalgae species in a continuous bench-scale conical Spouted Bed Reactor at 500 °C. Bio-gas, bio-oil and bio-char yields have been determined and characterized by using GC, GC/MS, elemental analyzer and SEM. Bio-oil was the main product obtained through pyrolysis of microalgae. The non-condensable gaseous stream is made up of mainly hydrogen, carbon monoxide and carbon dioxide, apart from other light hydrocarbons detected in lower concentration, as are methane, ethane, ethylene, propane and propylene. The compounds identified in the bio-oil have been categorized into hydrocarbons, nitrogen containing compounds, ketones, alcohols, acids, lactones, phenols and aldehydes. The nitrogen and carbon contents of the microalgae bio-chars are higher than those for bio-chars derived from other biomasses. Pyrolysis improved the morphology and porous structure of microalgae. Finally, the mechanism involving microalgae pyrolysis has been approached and the main reaction pathways have been proposed.
Javier Bilbao - One of the best experts on this subject based on the ideXlab platform.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Energy, 2022Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:Abstract The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence of temperature on the product yields has been analyzed in the 500–800 °C range. A detailed analysis of the volatile stream (condensable and non-condensable components) has been carried out by chromatographic techniques, and the char samples have been characterized by ultimate and proximate analyses, N2 adsorption-desorption, and Scanning Electron Microscopy. A high bio-oil yield was obtained at 500 °C (75.4 wt%), which is evidence of the suitable features of the conical Spouted Bed Reactor for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600 °C), and only had a little influence at 700 °C due to the low gas residence time in the conical Spouted Bed Reactor. At 800 °C, the reaction mechanism was controlled by gasification reactions. The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. Thus, phenolic compounds accounted for the major fraction at low pyrolysis temperatures, whereas hydrocarbons prevailed at 800 °C. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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conversion of hdpe into value products by fast pyrolysis using fcc spent catalysts in a fountain confined conical Spouted Bed Reactor
Chemsuschem, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Mayra Suarez, Martin OlazarAbstract:Continuous catalytic cracking of polyethylene over a spent fluid catalytic cracking (FCC) catalyst was studied in a conical Spouted Bed Reactor (CSBR) with fountain confiner and draft tube. The effect of temperature (475-600 °C) and space-time (7-45 gcat min gHDPE-1 ) on product distribution was analyzed. The CSBR allows operating with continuous plastic feed without defluidization problems and is especially suitable for catalytic pyrolysis with high catalyst efficiency. Thus, high catalyst activity was observed, with waxes yield being negligible above 550 °C. The main product fraction obtained in the catalytic cracking was made up of C5 -C11 hydrocarbons, with olefins being the main components. However, its yield decreased as temperature and residence time were increased, which was due to reactions involving cracking, hydrogen transfer, cyclization, and aromatization, leading to light hydrocarbons, paraffins, and aromatics. The proposed strategy is of great environmental relevance, as plastics are recycled using an industrial waste (spent FCC catalyst).
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pyrolysis of plastic wastes in a fountain confined conical Spouted Bed Reactor determination of stable operating conditions
Energy Conversion and Management, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Jon Alvarez, Martin OlazarAbstract:Abstract The performance of both fluidized and Spouted Bed Reactors in the pyrolysis of waste plastics is conditioned by particle agglomeration phenomena, which worsens the quality of the gas–solid contact and eventually lead to defluidization. The objective of this work is to determine the optimum conditions for stable operation (without defluidization) in a bench scale plant fitted with a fountain confined conical Spouted Bed Reactor and equipped with a nonporous draft tube, which operates in continuous mode. The insertion of these devices enhances the gas–solid contact, especially in the fountain region, and leads to a highly stable hydrodynamic regime, with these features being of especial relevance for the in situ catalytic pyrolysis of waste plastics. This paper deals with the effect different variables have on the minimum temperature for stable operation by avoiding defluidization. The variables analyzed are as follows: plastic type (HDPE, LDPE, PP, PS, PET and PMMA), plastic feed rate, mass of inert material in the Bed, spouting velocity and use of catalyst. The results show that polymers whose chains decompose at low temperatures or have high degrees of branching require low operating temperatures. Besides, as the ratio of Bed mass to plastic feed rate (WBed/Qplastic) and/or spouting velocity were increased, the temperature required to avoid defluidization was also reduced. The use of a catalyst also reduced the temperature required for stable operation, as the activation energy of cracking reactions is greatly reduced, and so reaction rate is increased.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Social Science Research Network, 2021Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence temperature in the 500-800 oC range has on the product yields has been analysed. A detailed analysis of the gaseous streamhas been carried out by chromatographic techniques, and the char samples have been characterized by several techniques.A high bio-oil yield was obtained at 500 oC (75.4 wt.%), which is evidence of the suitable features of the CSBR for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600oC), and only had a little influence at 700oC due to the low gas residence time in the CSBR. At 800 oC, the reaction mechanism was controlled by gasification reactions.The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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evolution of biomass char features and their role in the reactivity during steam gasification in a conical Spouted Bed Reactor
Energy Conversion and Management, 2019Co-Authors: Jon Alvarez, G. Lopez, Maider Amutio, Javier Bilbao, Martin OlazarAbstract:Abstract A study was carried out on the effect the evolution of the porous structure and metal content have on the gasification rate during char gasification in a conical Spouted Bed Reactor. Partially gasified samples at different temperatures (800–900 °C range) were collected at various conversion levels and characterized by different techniques (N 2 adsorption-desorption, ultimate/proximate analysis and X-ray Fluorescence). At 900 °C there is a fast development of the porous structure, attaining the highest BET specific surface area (S BET ) (633 m 2 g −1 ) at low conversion. Char reactivity profiles revealed that the development of the porous structure influenced the reaction rate mainly at early stages, whereas the increase in the gasification rate for conversions higher than 60% (especially at 900 °C) was attributed to the catalytic effect of Ca, K and Fe (the main metals in the ashes).
G. Lopez - One of the best experts on this subject based on the ideXlab platform.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Energy, 2022Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:Abstract The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence of temperature on the product yields has been analyzed in the 500–800 °C range. A detailed analysis of the volatile stream (condensable and non-condensable components) has been carried out by chromatographic techniques, and the char samples have been characterized by ultimate and proximate analyses, N2 adsorption-desorption, and Scanning Electron Microscopy. A high bio-oil yield was obtained at 500 °C (75.4 wt%), which is evidence of the suitable features of the conical Spouted Bed Reactor for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600 °C), and only had a little influence at 700 °C due to the low gas residence time in the conical Spouted Bed Reactor. At 800 °C, the reaction mechanism was controlled by gasification reactions. The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. Thus, phenolic compounds accounted for the major fraction at low pyrolysis temperatures, whereas hydrocarbons prevailed at 800 °C. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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conversion of hdpe into value products by fast pyrolysis using fcc spent catalysts in a fountain confined conical Spouted Bed Reactor
Chemsuschem, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Mayra Suarez, Martin OlazarAbstract:Continuous catalytic cracking of polyethylene over a spent fluid catalytic cracking (FCC) catalyst was studied in a conical Spouted Bed Reactor (CSBR) with fountain confiner and draft tube. The effect of temperature (475-600 °C) and space-time (7-45 gcat min gHDPE-1 ) on product distribution was analyzed. The CSBR allows operating with continuous plastic feed without defluidization problems and is especially suitable for catalytic pyrolysis with high catalyst efficiency. Thus, high catalyst activity was observed, with waxes yield being negligible above 550 °C. The main product fraction obtained in the catalytic cracking was made up of C5 -C11 hydrocarbons, with olefins being the main components. However, its yield decreased as temperature and residence time were increased, which was due to reactions involving cracking, hydrogen transfer, cyclization, and aromatization, leading to light hydrocarbons, paraffins, and aromatics. The proposed strategy is of great environmental relevance, as plastics are recycled using an industrial waste (spent FCC catalyst).
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pyrolysis of plastic wastes in a fountain confined conical Spouted Bed Reactor determination of stable operating conditions
Energy Conversion and Management, 2021Co-Authors: Santiago Orozco, Maite Artetxe, G. Lopez, Javier Bilbao, Jon Alvarez, Martin OlazarAbstract:Abstract The performance of both fluidized and Spouted Bed Reactors in the pyrolysis of waste plastics is conditioned by particle agglomeration phenomena, which worsens the quality of the gas–solid contact and eventually lead to defluidization. The objective of this work is to determine the optimum conditions for stable operation (without defluidization) in a bench scale plant fitted with a fountain confined conical Spouted Bed Reactor and equipped with a nonporous draft tube, which operates in continuous mode. The insertion of these devices enhances the gas–solid contact, especially in the fountain region, and leads to a highly stable hydrodynamic regime, with these features being of especial relevance for the in situ catalytic pyrolysis of waste plastics. This paper deals with the effect different variables have on the minimum temperature for stable operation by avoiding defluidization. The variables analyzed are as follows: plastic type (HDPE, LDPE, PP, PS, PET and PMMA), plastic feed rate, mass of inert material in the Bed, spouting velocity and use of catalyst. The results show that polymers whose chains decompose at low temperatures or have high degrees of branching require low operating temperatures. Besides, as the ratio of Bed mass to plastic feed rate (WBed/Qplastic) and/or spouting velocity were increased, the temperature required to avoid defluidization was also reduced. The use of a catalyst also reduced the temperature required for stable operation, as the activation energy of cracking reactions is greatly reduced, and so reaction rate is increased.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Social Science Research Network, 2021Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence temperature in the 500-800 oC range has on the product yields has been analysed. A detailed analysis of the gaseous streamhas been carried out by chromatographic techniques, and the char samples have been characterized by several techniques.A high bio-oil yield was obtained at 500 oC (75.4 wt.%), which is evidence of the suitable features of the CSBR for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600oC), and only had a little influence at 700oC due to the low gas residence time in the CSBR. At 800 oC, the reaction mechanism was controlled by gasification reactions.The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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biochars produced with fast flash pyrolysis in conical Spouted Bed Reactor potential for carbon sequestration
Linnaeus Eco-Tech, 2020Co-Authors: Renato Rocha Batista, G. Lopez, Marcia Martins MarquesAbstract:With the objective of verifying the potential for environmental applications of different chars produced by fast/flash pyrolysis in a conical Spouted Bed Reactor (CSBR), data/information was taken from previous studies, including 23 pyrogenic carbonaceous materials (PCM) produced with different anatomic parts of eight lignocellulosic biomasses as feedstocks, as follows: pinewood sawdust (Pin); poplar wood (Po); eucalyptus (Euc); orange waste (Ow); acacia (Ac); gorse (Car); rice husk (Rh) and; brow species mixture (Mix). These PCMs were classified according to Van Krevelen diagram (VK) (based on their O/C and H/C molar atomic ratios) and according to Spokas’ approach (based on their O/C molar atomic ratio). Since PCMs obtained with fast/flash pyrolysis tends to have underdeveloped structures as a result of short operation residence time (SRT) (0.05-0.11 s) and high heating rate (HR) (10³-104 °C/s), their properties are not favorable, for instance, for carbon sequestration. Even though, based on the O/C and H/C atomic ratios, all 23 PCMs met the international standards established by the Initiative Biochar Certificate (IBI) (H/C ≤ 0.7) and by the European Biochar Certificate (EBC) (O/C ≤ 0.4; H/C ≤ 0.7), being entitled to be named biochars. When the focus is placed on carbon sequestration applications, according to the EBC criterium (C ≥ 50%), besides the O/C and H/C ratio limits, four biochars obtained with rice husk biomasses were not eligible since their Carbon (C) content is Car (0.06; 0.34, 500°C) > Euc: (0.13; 0.35, 500°C) > Ow: (0.13; 0.43, 600°C) > Po: (0.14; 0.56, 525°C) > Ac: (0.16; 0.35, 500°C). However, the potential for environmental applications of these six biochars must be experimentally demonstrated since applications of biochars produced through CSBR are seldom reported in literature.
Maider Amutio - One of the best experts on this subject based on the ideXlab platform.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Energy, 2022Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:Abstract The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence of temperature on the product yields has been analyzed in the 500–800 °C range. A detailed analysis of the volatile stream (condensable and non-condensable components) has been carried out by chromatographic techniques, and the char samples have been characterized by ultimate and proximate analyses, N2 adsorption-desorption, and Scanning Electron Microscopy. A high bio-oil yield was obtained at 500 °C (75.4 wt%), which is evidence of the suitable features of the conical Spouted Bed Reactor for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600 °C), and only had a little influence at 700 °C due to the low gas residence time in the conical Spouted Bed Reactor. At 800 °C, the reaction mechanism was controlled by gasification reactions. The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. Thus, phenolic compounds accounted for the major fraction at low pyrolysis temperatures, whereas hydrocarbons prevailed at 800 °C. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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role of temperature in the biomass steam pyrolysis in a conical Spouted Bed Reactor
Social Science Research Network, 2021Co-Authors: Enara Fernandez, Maite Artetxe, G. Lopez, Maider Amutio, Javier Bilbao, Aitor Arregi, Laura Santamaria, Martin OlazarAbstract:The steam pyrolysis of pinewood sawdust has been conducted in a bench scale plant provided with a conical Spouted Bed Reactor (CSBR). This process is of uttermost relevance for the in-line valorisation of pyrolysis volatiles, specifically for their catalytic steam reforming for hydrogen production. The influence temperature in the 500-800 oC range has on the product yields has been analysed. A detailed analysis of the gaseous streamhas been carried out by chromatographic techniques, and the char samples have been characterized by several techniques.A high bio-oil yield was obtained at 500 oC (75.4 wt.%), which is evidence of the suitable features of the CSBR for this process. As temperature was increased, higher gas and lower liquid and char yields were obtained. Steam was fully inert at low pyrolysis temperatures (500-600oC), and only had a little influence at 700oC due to the low gas residence time in the CSBR. At 800 oC, the reaction mechanism was controlled by gasification reactions.The composition of the liquid fraction was considerably influenced by pyrolysis temperature, with a less oxygenated stream as temperature was increased. The char obtained in the whole temperature range can be further used as active carbon or energy source.
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on the pyrolysis of different microalgae species in a conical Spouted Bed Reactor bio fuel yields and characterization
Bioresource Technology, 2020Co-Authors: Kolsoom Azizi, G. Lopez, Maider Amutio, Aitor Arregi, Mostafa Keshavarz Moraveji, Martin OlazarAbstract:Abstract The aim of this work was to study fast pyrolysis of three microalgae species in a continuous bench-scale conical Spouted Bed Reactor at 500 °C. Bio-gas, bio-oil and bio-char yields have been determined and characterized by using GC, GC/MS, elemental analyzer and SEM. Bio-oil was the main product obtained through pyrolysis of microalgae. The non-condensable gaseous stream is made up of mainly hydrogen, carbon monoxide and carbon dioxide, apart from other light hydrocarbons detected in lower concentration, as are methane, ethane, ethylene, propane and propylene. The compounds identified in the bio-oil have been categorized into hydrocarbons, nitrogen containing compounds, ketones, alcohols, acids, lactones, phenols and aldehydes. The nitrogen and carbon contents of the microalgae bio-chars are higher than those for bio-chars derived from other biomasses. Pyrolysis improved the morphology and porous structure of microalgae. Finally, the mechanism involving microalgae pyrolysis has been approached and the main reaction pathways have been proposed.
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cfd modeling and experimental validation of biomass fast pyrolysis in a conical Spouted Bed Reactor
Journal of Analytical and Applied Pyrolysis, 2019Co-Authors: G. Lopez, Maider Amutio, Jon Alvarez, Bahar Hooshdaran, Maria Cortazar, M Haghshenasfard, Seyyed Hossein Hosseini, Martin OlazarAbstract:Abstract Biomass fast pyrolysis in a conical Spouted Bed Reactor has been modeled by coupling a kinetic model with Reactor hydrodynamics. The kinetic model proposed considers the influence of the two main parameters affecting the pyrolysis process, which are reaction temperature and residence time. Thus, the reaction scheme contemplates three parallel reactions for the formation of the pyrolysis products (gas, bio-oil and char) and a homogeneous secondary reaction in the gas phase, whose extent depends on the residence time of the pyrolysis volatiles. The experimental results used for calculating the kinetic parameters of best fit were obtained in a bench scale conical Spouted Bed Reactor equipped with a draft tube and operated in the 450–550 °C temperature range and with a gas residence time between 0.56 and 1.69 s. The model suitably predicts product formation rates and pyrolysis product yields in a wide range of reaction conditions. Moreover, a sensitivity analysis was carried out to evaluate the influence of the hydrodynamic parameters, as well as the model robustness.
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evolution of biomass char features and their role in the reactivity during steam gasification in a conical Spouted Bed Reactor
Energy Conversion and Management, 2019Co-Authors: Jon Alvarez, G. Lopez, Maider Amutio, Javier Bilbao, Martin OlazarAbstract:Abstract A study was carried out on the effect the evolution of the porous structure and metal content have on the gasification rate during char gasification in a conical Spouted Bed Reactor. Partially gasified samples at different temperatures (800–900 °C range) were collected at various conversion levels and characterized by different techniques (N 2 adsorption-desorption, ultimate/proximate analysis and X-ray Fluorescence). At 900 °C there is a fast development of the porous structure, attaining the highest BET specific surface area (S BET ) (633 m 2 g −1 ) at low conversion. Char reactivity profiles revealed that the development of the porous structure influenced the reaction rate mainly at early stages, whereas the increase in the gasification rate for conversions higher than 60% (especially at 900 °C) was attributed to the catalytic effect of Ca, K and Fe (the main metals in the ashes).
Gorka Elordi - One of the best experts on this subject based on the ideXlab platform.
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light olefins from hdpe cracking in a two step thermal and catalytic process
Chemical Engineering Journal, 2012Co-Authors: Maite Artetxe, Gorka Elordi, G. Lopez, Maider Amutio, Javier Bilbao, Martin OlazarAbstract:Abstract The continuous catalytic pyrolysis of high density polyethylene (HDPE) has been carried out in a two-step reaction system involving a pyrolysis conical Spouted Bed Reactor followed by a catalytic fixed Bed Reactor. The good performance of the conical Spouted Bed Reactor has allowed using a low temperature in thermal cracking (500 °C) without defluidization problems, obtaining a volatile stream with a 90 wt.% overall yield of C 12 –C 20 and waxes in the first step. The effect of the second-step operating conditions on product yields and composition has been studied using a catalyst based on a HZSM-5 (SiO 2 /Al 2 O 3 = 30) zeolite. The influence of temperature in the 350–550 °C range and space–time in the 0–8 g cat min g HDPE −1 range has been studied. An increase in temperature or space–time gives way to an increase in the yield of light olefins, reaching a value of 62.9 wt.% at 550 °C and 8 g cat min g HDPE −1 , with the individual yields of ethylene, propylene and butenes being 10.6, 35.6 and 16.7 wt.%, respectively. Although the yield of single-ring aromatics increases when both variables studied are increased, the maximum yield obtained was lower than 13 wt.%. The yield of waxes (the main product in the first step) is negligible even at low temperatures or spaces-times, which evidences the efficiency of the catalytic step.
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characterization of the waxes obtained by the pyrolysis of polyolefin plastics in a conical Spouted Bed Reactor
Journal of Analytical and Applied Pyrolysis, 2012Co-Authors: Miriam Arabiourrutia, Gorka Elordi, G. Lopez, Javier Bilbao, E Borsella, Martin OlazarAbstract:Abstract The thermal pyrolysis of three different polyolefin plastics (HDPE, LDPE and PP) has been carried out in a conical Spouted Bed Reactor. This technology is especially interesting because of the high selectivity to waxes due to the low residence times and high heating rates that reduce secondary reactions and increase the yield of primary pyrolysis products (waxes). These have been obtained operating at 450, 500 and 600 °C and a complete characterization has been carried out using different techniques, such as gel permeation chromatography (GPC), Fourier transform infrared (FTIR) spectrophotometry, simulated distillation and the measurement of heating value and melting point. Operating conditions and feed type have been observed to have a significant effect on the properties of the different waxes. The characterization has been carried out bearing in mind the potential use of waste plastic-derived waxes as a feedstock for cracking units.
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effect of the acidity of the hzsm 5 zeolite catalyst on the cracking of high density polyethylene in a conical Spouted Bed Reactor
Applied Catalysis A-general, 2012Co-Authors: Gorka Elordi, Maite Artetxe, Martin Olazar, Pedro Castano, Javier BilbaoAbstract:Abstract The catalytic cracking of high density polyethylene (HDPE) has been carried out at 500 °C in a conical Spouted Bed Reactor with two catalysts prepared with HZSM-5 zeolites with SiO2/Al2O3 ratios of 30 and 80. The polyethylene has been fed continuously (1 g min−1) over 10 h to a 30 g catalyst Bed. The results show the good performance of the conical Spouted Bed Reactor in minimising the limitations of the physical steps of the process. The deactivation of the catalysts is very low and it is demonstrated that the moderation of the acidity is useful in modifying the product distribution. The SiO2/Al2O3 ratio increment involves a decrease in the total acidity and in the acid strength, resulting in a higher yield of C2–C4 olefins and that of the non-aromatic C5–C11 fraction, and a decrease in the yields of aromatic components and C1–C4 paraffins. The yield of the C2–C4 olefins obtained with the HZSM-5 zeolite catalyst with a ratio of Si/Al2O3 = 80 is 59.8 wt% (that of propylene is 29.6 wt%) and the yield of the gasoline fraction (C5–C11) accounts for 32.1 wt%. The coke deposited on the catalyst has a heterogeneous nature and is constituted by two types of coke, which are deposited on the exterior and the interior of the crystalline channels of the HZSM-5 zeolite. The evolution of the coke is attenuated as the SiO2/Al2O3 ratio of the zeolite is increased.
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influence of temperature on biomass pyrolysis in a conical Spouted Bed Reactor
Resources Conservation and Recycling, 2012Co-Authors: Maider Amutio, Maite Artetxe, Gorka Elordi, G. Lopez, Martin Olazar, Javier BilbaoAbstract:Abstract Pinewood sawdust flash pyrolysis has been performed in continuous mode in a pilot plant provided with a conical Spouted Bed Reactor, in the 400–600 °C range. The influence of temperature on the pyrolysis yields and product properties has been studied. Product analysis has been carried out on-line by means of chromatographic methods. High liquid yields have been achieved, with the maximum bio-oil yield (75 wt%) at 500 °C. Gas yield is very low at low temperatures and this fraction is mainly composed of carbon dioxide, carbon monoxide and small amounts of methane, hydrogen and C2–C4 hydrocarbons. Bio-oil has been characterized and its major compounds are phenols, specifically guaiacols at low temperatures and catechols at high temperatures. At 600 °C, there is an increase in light compounds due to the cracking reactions, but no aromatic compounds have been detected due to the low residence time of the volatiles in the Reactor. The fuel properties of the bio-oil have been measured and the results indicate that it can be a potential substitute to conventional fuels, although its heating value should be improved by subjecting to further treatments. Char can be used as energy source or as active carbon. The char obtained at 600 °C has a high surface area and is suitable for active carbon production.
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product yields and compositions in the continuous pyrolysis of high density polyethylene in a conical Spouted Bed Reactor
Industrial & Engineering Chemistry Research, 2011Co-Authors: Gorka Elordi, Maite Artetxe, G. Lopez, Martin Olazar, Javier BilbaoAbstract:The pyrolysis of high-density polyethylene (HDPE) has been carried out in the range between 500 and 700 °C in continuous mode in a pilot-plant unit equipped with a conical Spouted Bed Reactor. The products have been grouped into the lumps of gas (C4–), gasoline (C5–C11), diesel (C12–C20), and waxes (C21+). The product yields and compositions of these fractions were compared both to those previously obtained in the pyrolysis performed in discontinuous mode and to those obtained by other authors in fluidized Bed Reactors. The results confirm the optimal performance of the conical Spouted Bed Reactor (CSBR) in obtaining high yields of waxes and fuels with low aromatic content, which is explained by the appropriate conditions of the CSBR needed to enhance heat and mass transfer between phases (capacity for coating the sand with plastic) and minimize secondary reactions (short residence time of the volatiles).