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Catalytic Fast Pyrolysis Of Biomass In A Bubbling Fluidized Bed Reactor With Gallium Promoted Zsm 5 Catalyst
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Book Synopsis Catalytic Fast Pyrolysis of Biomass in a Bubbling Fluidized Bed Reactor with Gallium Promoted ZSM-5 Catalyst by : Jian Shi
Download or read book Catalytic Fast Pyrolysis of Biomass in a Bubbling Fluidized Bed Reactor with Gallium Promoted ZSM-5 Catalyst written by Jian Shi and published by . This book was released on 2012 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: The huge energy demand of our society is causing fossil fuel resources to diminish rapidly. Therefore, it is critical to search for alternative energy resources. Biomass is currently both abundant and inexpensive. Biofuels (fuels produced from biomass) have the potential to replace fossil fuels if a cost effective process can be develop to convert biomass into fuels. Catalytic fast pyrolysis is a technology that can convert biomass into gasoline ranged aromatics in a single step. By heating biomass quickly to an intermediate temperature, biomass will thermally decompose into small molecules which can fit into zeolite catalyst pores. Inside the catalyst pores, these small molecules undergo a series of reactions where aromatics are formed along with olefins, CO, CO2, CH4 and water. Gallium promoted ZSM-5 catalyst has been shown to promote small alkanes aromatization, thus it has the potential to increase aromatic yield in catalytic fast pyrolysis process. The focus of the thesis is to study the behavior of catalyst fast pyrolysis of biomass over Gallium promoted catalyst, and explore various ways to utilize the gas phase olefins to increase the aromatic yield. [CG1] The effect of reaction parameters (temperature, weight hourly space velocity, and fluidized gas velocity) on catalytic fast pyrolysis of biomass with Ga/ZSM-5 were studied in a fluidized bed reactor using pine saw dust as the biomass feed. The product distribution and hydrocarbon selectivity are shown to be a strong function of temperature and weight hourly space velocity. Compared to ZSM-5 catalyst at the same reaction conditions, Ga/ZMS-5 has been shown to increase the aromatic yield by 40%. Olefins can be recycled back to the CFP fluidized bed reactor to further increase the aromatic yield. The olefin co-feeding with pine saw dust experiments indicates that co-feeding with propylene can increase the aromatic yield, however, co-feeding with ethylene will cause a decrease in aromatic yield. In both co-feeding experiments, an increase in the amount of coke formed was also observed. Besides a simple olefin recycle, another possible way to utilize these olefins, while avoiding the high cost to separate them from other gas phase products (CO, CO2 and CH4), is adding a secondary alkylation unit after the fluidized bed reactor. The alkylation unit could provide a way to produce additional ethylbenzene after the main CFP process. Three zeolite catalysts (ZSM-5, Y-zeolite and Beta zeolite) were tested in the alkylation unit, and ZSM-5 catalyst shows the highest activity and selectivity in the alkylation of benzene and ethylene.
Book Synopsis Design of Fluidized-bed Reactors for Catalytic Fast Pyrolysis by : Robert John Ng Coolman
Download or read book Design of Fluidized-bed Reactors for Catalytic Fast Pyrolysis written by Robert John Ng Coolman and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The net accumulation of atmospheric carbon resulting from the increase in global demand for fuels and chemicals from fossil sources warrants the search for alternatives that fit into existing infrastructure ("drop-in" chemicals and fuels) that come from renewable sources. The research presented in this thesis progresses this search for alternatives through the study of Catalytic Fast Pyrolysis (CFP) of renewable lignocellulosic biomass in bubbling fluidized beds of ZSM-5. For CFP of cellulose at 500°C using a 4.92-cm ID reactor, aromatic yields of up to 39.5% carbon were obtained indicating the importance of high-cellulose feeds for production of aromatics. In a larger 9.67-cm ID process development unit (PDU) with on-stream catalyst input and output, we studied CFP of pine sawdust. The PDU maintained constant product yield of aromatics (15.5% carbon) over an extended reaction period (6 hrs). A simulated recycle stream of CFP product gases consisting of CO, CO2 and olefins increased aromatic yield to 22% carbon in contrast to nitrogen which produced only 18% yield. In a third 4.92-cm ID reactor, the effect of steam for the CFP of cellulose with ZSM-5 was studied. Irreversible effects included dealumination, a loss of total acidity, an increase in the zeolite-crystal size, and agglomeration of particles resulting in lower yields for aromatics and coke, and higher yields for methane and unidentified products. Steam co-feeding was also found to reversibly lower yields of aromatics, char/coke, and identifiable oxygenate species, increase yields of CO and methane, and not change the overall yields of CO2 and olefins. The effect of catalyst contact time was studied at coke loadings known not to deactivate the catalyst. CO and CH4 are favored at low catalyst contact times (1,000 s), oxygenated and unidentified species at medium catalyst contact times (1,000 s -- 10,000 s), and aromatics and CO2Ơ at high catalyst contact times (10,000 s). At increased time on stream, the catalyst lost activity due to coking. Most aromatic-producing activity was lost after a weight turnover of 2.0. Accumulated coke deactivates the catalyst by both filling the micropores and blocking the acid sites
Book Synopsis Catalytic Fast Pyrolysis of Furan Over ZSM-5 Catalysts by : Yu-Ting Cheng
Download or read book Catalytic Fast Pyrolysis of Furan Over ZSM-5 Catalysts written by Yu-Ting Cheng and published by . This book was released on 2012 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to its low cost and availability, lignocellulosic biomass is receiving significant attention worldwide as a feedstock for renewable liquid bio-fuels. We have recently shown that zeolites can be added to a pyrolysis reactor to directly make aromatics from solid biomass in one single step in a process called catalytic fast pyrolysis (CFP). The advantage of this approach is that valuable petrochemicals can be made directly from solid biomass in a single catalytic step using zeolite catalysts. However, little is known about the conversion chemistry that occurs within the zeolites during CFP. The objective of this thesis is to identify the key catalytic reactions that occur for conversion of biomass inside ZSM-5 zeolite catalysts using furan and its derivatives as model biomass compounds. The kinetic data and chemistry was obtained by using a continuous flow fixed-bed reactor, and an in-situ temperature-programmed reactor system. Furan adsorbs as oligomers at room temperature. These oligomers are converted into CO, CO2, H2O, olefins, monocyclic aromatics, and undesired polycyclic aromatics and coke at 400 - 600°C. An important route to form aromatics at 600°C is Diels-Alder reaction/dehydration where furan reacts with produced olefins and forms aromatics and water. The Diels-Alder reaction can be further utilized by co-feeding olefins with furanic compounds to tune the aromatics distribution. For example, in our experiments we were able to double toluene and triple xylenes selectivity for furan and 2-methylfuran CFP, respectively. Moreover, we synthesized a series of Ga-promoted catalysts to increase the rate of aromatics production. The aromatics selectivity obtained from furan conversion over Ga-containing ZSM-5 was 40% higher than unpromoted ZSM-5. The promotion was also observed in a bubbled fluidized-bed reactor used for pinewood CFP, where the aromatics yield was increased by 50% using a Ga-promoted ZSM-5 FCC catalyst. We finally fine-tuned ZSM-5 pores to impose more space confinement on aromatic products. These modified ZSM-5 increased p-xylene selectivity in xylenes from 32% to greater than 90% for conversion of 2-methylfuran and propylene while the overall p-xylene selectivity was increased from 5% to 15%. The Ga promotional effect was also observed on a spray-dried ZSM-5 catalyst. This study addresses the catalytic chemistry that occurs inside zeolites during CFP of biomass into aromatics using furan as a model biomass compound. Understanding this reaction chemistry can give us insight into how to design more effective zeolite catalysts and reactors for the efficient utilization of our biomass resources.
Book Synopsis Recycling of Solid Waste for Biofuels and Bio-chemicals by : Obulisamy Parthiba Karthikeyan
Download or read book Recycling of Solid Waste for Biofuels and Bio-chemicals written by Obulisamy Parthiba Karthikeyan and published by Springer. This book was released on 2016-08-10 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest advances in and current research perspectives on the field of urban/industrial solid waste recycling for bio-energy and bio-fuel recovery. It chiefly focuses on five main thematic areas, namely bioreactor landfills coupled with energy and nutrient recovery; microbial insights into anaerobic digestion; greenhouse emission assessment; pyrolysis techniques for special waste treatment; and industrial waste stabilization options. In addition, it compiles the results of case studies and solid waste management perspectives from different countries.
Book Synopsis Fast Pyrolysis of Biomass by : Robert C Brown
Download or read book Fast Pyrolysis of Biomass written by Robert C Brown and published by Royal Society of Chemistry. This book was released on 2017-06-30 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fast pyrolysis and related catalytic pyrolysis are of increasing interest as pathways to advanced biofuels that closely mimic traditional petroleum products. Research has moved from empirical investigations to more fundamental studies of pyrolysis mechanisms. Theories on the chemical and physical pathways from plant polymers to pyrolysis products have proliferated as a result. This book brings together the latest developments in pyrolysis science and technology. It examines, reviews and challenges the unresolved and sometimes controversial questions about pyrolysis, helping advance the understanding of this important technology and stimulating discussion on the various competing theories of thermal deconstruction of plant polymers. Beginning with an introduction to the biomass-to-biofuels process via fast pyrolysis and catalytic pyrolysis, chapters address prominent questions such as whether free radicals or concerted reactions dominate deconstruction reactions. Finally, the book concludes with an economic analysis of fast pyrolysis versus catalytic pyrolysis. This book will be of interest to advanced students and researchers interested in the science behind renewable fuel technology, and particularly the thermochemical processing of biomass.
Book Synopsis Comparison Between Catalytic Fast Pyrolysis and Catalytic Fast Hydropyrolysis of Arundo Donax in a Fluidized Bed Reactor by : Devin Chandler
Download or read book Comparison Between Catalytic Fast Pyrolysis and Catalytic Fast Hydropyrolysis of Arundo Donax in a Fluidized Bed Reactor written by Devin Chandler and published by . This book was released on 2018 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, we report the use of catalytic fast pyrolysis with HZSM-5 to convert Arundo Donax into liquid transportation fuels in an inert atmosphere, varying the temperature, the weight hourly space velocity (abbreviated WHSV, and defined as the feed rate of biomass divided by the weight of catalyst), and the pressure. We also introduced hydrogen gas as a reactant and investigated its effects on the yields at 35 bar and 400°C. Additionally, we added nickel to the HZSM-5 catalyst at loadings from 0.6 to 1.5 wt.% and investigated its effects on both catalytic fast pyrolysis and catalytic fast hydropyrolysis. Finally, we used a nickel-molybdenum HZSM-5 catalyst to determine if the molybdenum prevents the hydrocarbons from cracking to permanent gases. The goal is to understand the effects of these variables on the products of pyrolysis and increase the yield of fuel-like hydrocarbons. The highest yield of hydrocarbons in an inert atmosphere at atmospheric pressure was obtained at 550°C (11.6 C%). As we increased the WHSV, the yields of all products remained the same until the highest WHSV tested, 3.3 hr−1, at which point the yield of hydrocarbons decreased to 6.9 C%. Increasing the pressure increased the char and gas yields. The addition of hydrogen decreased the yield of coke and increased the yield of hydrocarbons at 400°C from 4.3 to 6.2 C%. Nickel decreased the yield of liquid hydrocarbons to 1.5 C% in hydrogen gas while greatly increasing the yield of gaseous hydrocarbons, especially methane, and water, though it had little effect in inert gas. Finally, we used nickel-molybdenum HZSM-5 to increase the yield of liquid hydrocarbons in catalytic fast hydropyrolysis to 7.9 C% at 400°C.
Book Synopsis Production of Biofuels and Chemicals with Pyrolysis by : Zhen Fang
Download or read book Production of Biofuels and Chemicals with Pyrolysis written by Zhen Fang and published by Springer Nature. This book was released on 2020-10-27 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a collection of studies on state-of-art techniques for converting biomass to chemical products by means of pyrolysis, which are widely applicable to the valorization of biomass. In addition to discussing the fundamentals and mechanisms for producing bio-oils, chemicals, gases and biochar using pyrolysis, it outlines key reaction parameters and reactor configurations for various types of biomass. Written by leading experts and providing a broad range of perspectives on cutting-edge applications, the book is a comprehensive reference guide for academic researchers and industrial engineers in the fields of natural renewable materials, biorefinery of lignocellulose, biofuels, and environmental engineering, and a valuable resource for university students in the fields of chemical engineering, material science and environmental engineering.
Book Synopsis Catalytic Pyrolysis of Biomass in a Fluidized Bed Reactor by : Ali Reza Shariat
Download or read book Catalytic Pyrolysis of Biomass in a Fluidized Bed Reactor written by Ali Reza Shariat and published by . This book was released on 1984 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Conceptual Process Design and Techno-economic Assessment of Ex Situ Catalytic Fast Pyrolysis of Biomass by :
Download or read book Conceptual Process Design and Techno-economic Assessment of Ex Situ Catalytic Fast Pyrolysis of Biomass written by and published by . This book was released on 2015 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ex situ catalytic fast pyrolysis of biomass is a promising route for the production of fungible liquid biofuels. There is significant ongoing research on the design and development of catalysts for this process. However, there are a limited number of studies investigating process configurations and their effects on biorefinery economics. Herein we present a conceptual process design with techno-economic assessment; it includes the production of upgraded bio-oil via fixed bed ex situ catalytic fast pyrolysis followed by final hydroprocessing to hydrocarbon fuel blendstocks. This study builds upon previous work using fluidized bed systems, as detailed in a recent design report led by the National Renewable Energy Laboratory (NREL/TP-5100-62455); overall yields are assumed to be similar, and are based on enabling future feasibility. Assuming similar yields provides a basis for easy comparison and for studying the impacts of areas of focus in this study, namely, fixed bed reactor configurations and their catalyst development requirements, and the impacts of an inline hot gas filter. A comparison with the fluidized bed system shows that there is potential for higher capital costs and lower catalyst costs in the fixed bed system, leading to comparable overall costs. The key catalyst requirement is to enable the effective transformation of highly oxygenated biomass into hydrocarbons products with properties suitable for blending into current fuels. Potential catalyst materials are discussed, along with their suitability for deoxygenation, hydrogenation and C-C coupling chemistry. This chemistry is necessary during pyrolysis vapor upgrading for improved bio-oil quality, which enables efficient downstream hydroprocessing; C-C coupling helps increase the proportion of diesel/jet fuel range product. One potential benefit of fixed bed upgrading over fluidized bed upgrading is catalyst flexibility, providing greater control over chemistry and product composition. Since this study is based on future projections, the impacts of uncertainties in the underlying assumptions are quantified via sensitivity analysis. As a result, this analysis indicates that catalyst researchers should prioritize by: carbon efficiency> catalyst cost> catalyst lifetime, after initially testing for basic operational feasibility.
Book Synopsis Computational Study on Biomass Fast Pyrolysis by : Emilio Ramirez (Chemical engineer)
Download or read book Computational Study on Biomass Fast Pyrolysis written by Emilio Ramirez (Chemical engineer) and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluidized bed reactors are utilized in a wide range of chemical industries, including petroleum refining, pharmaceutical and commodity chemicals production, and biomass conversion to fuels and higher-value chemicals. Such reactors are useful where multiple fluids (gases or liquids) and particulate solids are brought together in intimate contact to promote heat and mass transfer and chemical reactions. Recently fluidized-bed research includes computational simulations that provide new insights into the dominant physics and chemistry processes that control reactor performance. Computational simulations were utilized to understand how bubbling-bed hydrodynamics and fast-pyrolysis chemistry interact to control biomass pyrolysis reactor performance. The scope of this work is limited to bubbling bed conditions, designed and operated for lab scale studies of biomass fast pyrolysis, in a bed of inert Geldart Group B sand. Biomass particulates are injected near the bottom of the reactor and rapidly heated to release volatile compounds. The devolatilized biomass particles (char) and released volatile gases transit through the bed (at time scales depending on the hydrodynamic mixing state) and elutriate from the top of the reactor. The bubbling-bed hydrodynamics were simulated with MFiX, an open- source software package based on the two-fluid (continuum) approach for representing the bubbling bed multiphase flows. Processes of interest included the transport of biomass char and released volatile gases, and how these change with fluidizing gas flow, low-intensity bubbling, to slugging, to high- intensity turbulence. A key observation is that fast-pyrolysis tar yield can be increased by reducing the residence time in the freeboard by shortening the freeboard length or by adding secondary air. Also, of interest was how these transport processes are expected to affect the selectivity of product species exiting the top of the reactor. One promising concept for monitoring hydrodynamics in bubbling bed reactors are high- speed pressure measurements to quantify key mixing and transport properties. Computational simulations were utilized to identify quantitative statistical features in high-speed pressure measurements in the upper section of the bed, below the static bed height, to use as process monitoring tools. Other promising directions were identified for future experimental and computational studies.
Book Synopsis Production of Hydrocarbons from Biomass Using the Waterloo Fast Pyrolysis Process by : University of Waterloo. Department of Chemical Engineering
Download or read book Production of Hydrocarbons from Biomass Using the Waterloo Fast Pyrolysis Process written by University of Waterloo. Department of Chemical Engineering and published by . This book was released on 1992 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earlier work in the laboratory had shown that it was possible to hydrogasify wood directly at atmospheric pressure in a fluidized bed of nickel catalyst at operating conditions corresponding to those that were optimal for maximum liquid yields in the Waterloo fast pyrolysis process. It was thought that it might be possible to produce higher hydrocarbons by the same method with suitably modified catalysts. This project investigated the possibility of direct single step production of light hydrocarbons (C2+) from wood or cellulose by a process called catalytic hydropyrolysis. A wide range of catalytic metals, singly or in combination, were investigated, as well as three supports. Metals investigated include iron, nickel, cobalt, zinc, zirconium, chromium, molybdenum, tungsten, silicon, aluminum, titanium, and magnesium.
Book Synopsis Computational Modelling of the Fast Pyrolysis of Biomass in Bubbling Fluidised Bed Reactors by : Konstantinos Papadikis
Download or read book Computational Modelling of the Fast Pyrolysis of Biomass in Bubbling Fluidised Bed Reactors written by Konstantinos Papadikis and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis New and Future Developments in Catalysis by : Li Li
Download or read book New and Future Developments in Catalysis written by Li Li and published by Elsevier Inc. Chapters. This book was released on 2013-07-17 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Psalmer og aandelige Sange ved Barnedaab, Bryllup og Begravelse by :
Download or read book Psalmer og aandelige Sange ved Barnedaab, Bryllup og Begravelse written by and published by . This book was released on 1861 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Renewable Fuels Produced from Biomass Pyrolysis Vapors: Catalysis and Reaction Engineering by : David Pierce Gamliel
Download or read book Renewable Fuels Produced from Biomass Pyrolysis Vapors: Catalysis and Reaction Engineering written by David Pierce Gamliel and published by . This book was released on 2018 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: At present, lignocellulosic biomass is the only renewable and available resource capable of supplanting fossil fuel resources. Fast pyrolysis is the conversion of biomass at elevated temperature, high heating rate and under inert atmosphere to produce bio-oil. This bio-oil is a blend of oxygenated hydrocarbons, which must be upgraded prior to use as a transportation fuel. The focus of this thesis is the investigation of bio-oil upgrading reaction pathways and catalysts for the production of biofuels. There are two primary pathways for pyrolysis vapor upgrading: catalytic cracking and hydrodeoxygenation (HDO). During catalytic cracking, pyrolysis vapors react over the acid sites of ZSM-5 zeolite, which crack C-C bonds to release oxygen in the form of COx. Biofuel compound yield is greater when cracking occurs in-situ the pyrolysis reactor, but selectivity is greater when cracking occurs ex-situ. Because of its microporous structure, the ZSM-5 catalyst may exclude some of the bulky oxygenates formed during pyrolysis. This accessibility limitation can be alleviated through the introduction of mesoporosity in the ZSM-5 zeolite. Zeolite mesoporosity is beneficial for increasing aromatic yield and reducing coke on catalyst. While catalytic cracking is effective for removing oxygen from the pyrolysis vapors, this oxygen is removed as COx, reducing carbon return in the bio-oil. Moreover, the upgraded bio-oil is aromatic in nature, and aromatics in gasoline are limited. Incorporation of hydrogen into the pyrolysis reactor in the presence of Ni-ZSM-5 catalyst reduces char formation and substantially increases CH4 yield, but the bio-oil does not contain many alkanes. The high reaction temperature demanded by biomass volatilization thermodynamically limits hydrogenation reactions. Catalytic hydropyrolysis followed by secondary hydroprocessing produces a biofuel with heating value and aromaticity similar to gasoline. Liquid phase HDO is another pathway for removal of bio-oil oxygen. Catalytic HDO of anisole, 4-ethylphenol and benzofuran was performed with Ni, Ru and Pd supported on USY zeolite. Kinetic rate measurements show Pd is more effective than Ni and Ru in terms of reaction rate, deoxygenation activity and C-C coupling. Finally, controlled mesoporosity of the USY support is beneficial for enhancing access of oxygenates to the impregnated metal species for efficient hydrogenation.
Book Synopsis Optimization of Mixing in a Simulated Biomass Bed Reactor with a Center Feeding Tube by : Michael T. Blatnik
Download or read book Optimization of Mixing in a Simulated Biomass Bed Reactor with a Center Feeding Tube written by Michael T. Blatnik and published by . This book was released on 2013 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Producing gasoline-type fuels from lignocellulosic biomass has two advantages over producing alcohol-type fuels from plant sugars: gasoline has superior fuel characteristics and plant lignin/cellulose does not compete with human food supplies. A promising technology for converting lignocellulose to fuel is catalytic fast pyrolysis (CFP). The process involves injecting finely ground biomass into a fluidized bed reactor (FBR) at high temperatures, which reduce the biomass to gases that react inside the catalyst particles. This entails complex hydrodynamics to efficiently mix a stream of biomass into a catalyst bed that is fluidized by a separate stream of inert gas. Understanding the hydrodynamics is complicated by the fact that the entire process occurs inside a heavily insulated, opaque, reactor vessel. Numerical simulations offer a promising approach to understanding, predicting, and optimizing hydrodynamic mixing in a CFP biomass reactor. The purpose of this research is to understand the simulation techniques and statistical measures appropriate for quantifying mixing in a CFP biomass reactor. The methodology is validated against the canonical configuration of a non-reacting, single-inlet fluidized bed. A new finding is that the minimum bubbling velocity may be predicted by a significant increase in temporal variance of the pressure drop. The methodology is then applied to a non-canonical FBR in which biomass is injected into the catalyst bed via a vertical center tube. Since no hydrodynamic mixing data exist from laboratory experiments, mixing is inferred from the aromatics yield from the laboratory reactor. Flow configurations with which simulations demonstrate the best mixing have the highest aromatic yields in the experiments. The simulations indicate that when the bed is in the bubbling regime, the gasified biomass from the center tube is efficiently mixed radially throughout the catalyst bed. If the flow rate of inert gas is insufficient to bubble the bed, then the gasified biomass exits the center tube, reverses direction, and flows upward along the tube's outside wall. Provided the bed is bubbling due to the inert gas stream, the upper limit on the flow through the center tube, and thus the aromatic yield potential, has yet to be determined.
Book Synopsis Comparison of the Effect of Pre-treatment and Catalysts on Liquid Quality from Fast Pyrolysis of Biomass by : Antzela Fivga
Download or read book Comparison of the Effect of Pre-treatment and Catalysts on Liquid Quality from Fast Pyrolysis of Biomass written by Antzela Fivga and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall objective of this work was to compare the effect of pre-treatment and catalysts on the quality of liquid products from fast pyrolysis of biomass. This study investigated the upgrading of bio-oil in terms of its quality as a bio-fuel and/or source of chemicals. Bio-oil used directly as a biofuel for heat or power needs to be improved particularly in terms of temperature sensitivity, oxygen content, chemical instability, solid content, and heating values. Chemicals produced from bio-oil need to be able to meet product specifications for market acceptability. There were two main objectives in this research. The first was to examine the influence of pre-treatment of biomass on the fast pyrolysis process and liquid quality. The relationship between the method of pre-treatment of biomass feedstock to fast pyrolysis oil quality was studied. The thermal decomposition behaviour of untreated and pretreated feedstocks was studied by using a TGA (thermogravimetric analysis) and a Py-GC/MS (pyroprobe-gas chromatography/mass spectrometry). Laboratory scale reactors (100g/h, 300g/h, 1kg/h) were used to process untreated and pretreated feedstocks by fast pyrolysis. The second objective was to study the influence of numerous catalysts on fast pyrolysis liquids from wheat straw. The first step applied analytical pyrolysis (Py- GC/MS) to determine which catalysts had an effect on fast pyrolysis liquid, in order to select catalysts for further laboratory fast pyrolysis. The effect of activation, temperature, and biomass pre-treatment on catalysts were also investigated. Laboratory experiments were also conducted using the existing 300g/h fluidised bed reactor system with a secondary catalytic fixed bed reactor. The screening of catalysts showed that CoMo was a highly active catalyst, which particularly reduced the higher molecular weight products of fast pyrolysis. From these screening tests, CoMo catalyst was selected for larger scale laboratory experiments. With reference to the effect of pre-treatment work on fast pyrolysis process, a significant effect occurred on the thermal decomposition of biomass, as well as the pyrolysis products composition, and the proportion of key components in bio-oil. Torrefaction proved to have a mild influence on pyrolysis products, when compared to aquathermolysis and steam pre-treatment.
