Chemical engineering and reactor design of a fluidised bed gasifier. Water yields were similar in the range of 1116 wt%. Pyrolysis proceeds in the absence of o 2 and takes seconds only at moderate temperatures 500 c. The industrial thermochemical conversion itc group provides expertise in thermochemical conversion processes that involve multiphase particulate flows and fluidized bed systems. Experimental study of biomass pyrolysis in a fluidized bed. Pyrolysis reactor an overview sciencedirect topics. Within the common pyrolysis reactor designs, mostly fluidised beds are applied. Integration of the filter system in the fluidized bed should overcome operational problems related to the increase in. This book focuses on the design and operation of fluidized beds in many different industrial processes, emphasizing the rationale for choosing fluidized beds for each particular process. Present reactors for flash pyrolysis include fluidized bed reactors, vacuum pyrolysis reactor, rotating cone reactor, entrained flow.
The pyrolysis occurs by introducing biomass and steam to a hot fluidized bed of inert material such as coarse sand. The fluidized bed reactor danny lathouwers and josette bellan jet propulsion laboratory california institute of technology pasadena, ca 911088099 abstract a numerical study is performed in order to evaluate the performance and optimal operating condi. Thus, the benefits of using fluidized bed technology can easily outweigh the disadvantages, especially for processes. Pdf design of a fluidized bed reactor for biomass pyrolysis. Finally, the process flow diagram of a typical biomass. Thermal pyrolysis of polyethylene in fluidized beds. Ablative pyrolysis is substantially different in concept compared to the other methods of fast pyrolysis. Process schematic for a circulating fluidized bed pyrolysis design 10 figure 3. Some of these reactors are, 1 fixed bed reactor 2 free fall reactor 3 fluidized bed reactor induction heating reactor 5 fixed bed catalytic reactor out of these reactors fixed bed reactor is easy to. Gasification, pyrolysis, and combustion chapter 15. Initially, a study was conducted to understand the hydrodynamics of the fluidised bed reactor by. The design was inspired by tylers concept, but incorporated several additional features. This project presents a specified design of a smallscale fixed bed reactor for the purpose of investigating the gasification processes of biomass and municipal solid wastes.
Numerical simulation of biomass fast pyrolysis in fluidized. A study of the design of fluidized bed reactors for biomass gas ification ucl i i ajmal latifmeng. Fluidized bed reactor is taken numerical simulation by cfd software fluent. Because of the expansion of the bed materials in the reactor, a larger vessel is often required than that for a packed bed reactor.
Fast pyrolysis of biomass in a circulating fluidised bed. Circulating fluidized bed bubbling fluidized bed ablative pyrolysis rotating cone 2 the 12th international conference on fluidization new horizons in fluidization engineering, art. Schematic of the nrel vortex reactor fast pyrolysis reactor design 11 figure 4. The text contains various studies, facts, and discussions on fluidized beds. In this type of reactor, a fluid gas or liquid is passed through a solid granular material usually a catalyst possibly shaped as tiny spheres at high enough velocities to suspend the solid and cause it to behave as though it were a fluid. Catalytic fast pyrolysis of biomass in a bubbling fluidized. The influence of bed temperature on the yield of pyrolysis products a first series of tests were carried out for both polymers at a fixed fluidizing gas velocity, u. The purpose of initial fluidized bed design was coal gasification 79.
Various types of pyrolysis reactors were designed for production of biooil from different agricultural wastes. In fluidized bed reactors, the carrier gas is extremely important because it also acts to lift the solids and fluidize the biomasssand slurry. Fluidized bed fast pyrolysis of biomass is considered as having a high commercial. Bed a in figure 2 is the combustion fluidized bed, while bed b is the pyrolysis fluidized bed. Molecular beam mass spectrometer scans of pyrolysis product profile at different. Using this novel fluidised bed, gravimetric measurements and high heating rate, the thermal conversion of biomass was investigated. The product distribution and hydrocarbon selectivity are shown to be a strong function of temperature and weight hourly space velocity. Recently the petrochemical industry uses fluidized bed for catalytic processes such as residue fluidized catalytic cracking rfcc 1. The itc group fixed and fluidized bed research and.
Pdf design and operation of a low cost biooil fast pyrolysis from. The system is intended to generate fuel reactivity data rapidly and cheaply, under realistic experimental conditions. Design consideration of pyrolysis reactor for production of. The rotating cone reactor has many similarities except that the sand and biomass transport is effected by centrifugal forces operating in a rotating cone. Most of the heat transfer in fast pyrolysis reactors is through solidsolid conduction contact between the biomass and. Pyrolysis of softwood carbohydrates in a fluidized bed reactor. The very good heat and material transfer, and the consequent almost constant temperature inside the reactor, provides for a relatively uniform. Chemical engineering and reactor design of a fluidised bed. A system to remove in situ charash from hot pyrolysis vapors has been developed and tested at the university of twente. Dual fluidized bed biomass gasification unt digital library. The short residence times encountered in the reactor result in higher gas velocities, faster vapor and char escape and higher char content in the biooil than bubbling fluidized beds. Fluidized bed is one of the reactors using fluidization 24. Char is a cracking catalyst for biooil and must be removed from the vapour. Fast pyrolysis of biomass in a spoutfluidized bed reactor analysis of composition and combustion characteristics of.
Rahul in partial fulfillments for the requirements for the award of bachelor of technology degree in mechanical engineering at national institute of technology, rourkela deemed university is an authentic. The fluidized bed reactor is the centerpiece of industrial fluidization processes. In the present work pyrolysis of pure pine wood and softwood carbohydrates, namely cellulose and galactoglucomannan the major hemicellulose in coniferous wood, was conducted in a batch mode operated fluidized bed reactor. Pyrolysis and gasification in a benchscale highpressure. Design, fabrication and performance test of a fixed bed batch type. Biomass gasification, pyrolysis and torrefaction 2nd edition. Integrated particle and reactor scale simulation of pine pyrolysis in a fluidized bed. Circulating fluidized bed technology ii is a result of a series of sciencerelated conferences in the 1980s.
Fluidization occurs when small solid particles are suspended in an upwardflowing stream of fluid, as shown in figure r12. Biomass pyrolysis equipment designed independently consists of feeding system with twostage screw feeder, fluidized bed reactor, cyclone separator system, condensation system and control system. The use of a fluidized bed reactor was investigated for the synthesis of cnts on a continuous basis, and in bulk. Apr 21, 2009 a system to remove in situ charash from hot pyrolysis vapors has been developed and tested at the university of twente. Gas extraction ports are evenly distributed along the height of the reactor to extract product gases and accommodate thermocouples for temperature measurement. Investigation of ammonia formation during gasification in an airblown spouted bed. Oct 11, 2005 integrated particle and reactor scale simulation of pine pyrolysis in a fluidized bed. Rahul in partial fulfillments for the requirements for the award of bachelor of technology degree in. A fluidized bed reactor fbr is a type of reactor device that can be used to carry out a variety of multiphase chemical reactions. Viswanathan,department of chemical engineering,iit bombay. Fast pyrolysis of pakistani cotton stalks in fluidized bed.
Pdf on jan 12, 2019, alaba olumide bamido and others published design of a. Predictions of existing single particle models derived from a detailed description of the transport phenomena and literature data on measured intrinsic chemical kinetics are presented. Two different pyrolysis experiments were performed. The volatile content of the char products were higher for the ablative, compared to the results for the fluid bed chars which showed a continual rapid decrease. Bed agglomeration during biooil fast pyrolysis in a fluidized bed reactor. In this work, a fluidized bed reactor model for biomass fast pyrolysis was developed and applied to the bells corners complex bcc fluidized bed fast pyrolysis unit located at nrcan canmetenergy ottawa, canada for testing and validation. Syngas is produced during the pyrolysis and exits the top of the reactor with the steam. Entrained flow or fluidized bed reactors are considered the best reactors for this purpose. Analysis of wood biomass in bubbling fluidized bed reactors. Scribd is the worlds largest social reading and publishing site. Process schematic for a bubbling fluidized bed pyrolysis design 9 figure 2. The book begins by going through the rise and fall of circulating systems, specifically fluid dynamics. Consequently, a detailed design of a fluidized bed reactor that would allow flexible operation at high temperature and high pressure at several gas velocities will be conducted in order to serve for the future development of new hydrodynamic models.
Catalytic process, catalytic reactor, fixed bed reactor, reversal flow, fluidized bed reactor, biocatalytic reactors, unconventional reactors, membrane. A schematic diagram of the reactor is shown in fig. Present reactors for flash pyrolysis include fluidized bed reactors, vacuum pyrolysis reactor, rotating cone reactor, entrained flow reactor, ablative, vortex or blade, twin screw reactors. The designs of fixed bed reactors are often carried out with some simplifications, such as assumption of plug flow.
After condensation, a brown, low viscosity liquid is obtained. Development of a circulating fluidized bed reactor model for the. Design consideration of pyrolysis reactor for production. Important design issues are kinetics, modelling and reactor hydrodynamics 3,4. A fluidized bed reactor based experimental setup was designed and fabricated for this study which had an overall goal of investigating different techniques to improve the physical and chemical properties of biooil obtained from fast pyrolysis of biomass. Agricultural residues can be converted in the biofuels to fulfil the world energy demands and achieve the targets set by different countries to replace fossil fuels with renewable resources. With a dedicated focus on the design, analysis, and operational aspects of biomass gasification, pyrolysis, and torrefaction, biomass gasification, pyrolysis and torrefaction, second edition offers comprehensive coverage of biomass in its gas, liquid, and solid states in a single easytoaccess source. The air gasification of sawdust with a fluidized bed reactor. As in any design, the fluidized bed reactor does have it drawbacks, which any reactor designer must take into consideration. They require high gas flows in lower liquid yields. The fluidized bed was mounted on a vertically mobile supportplate, enabling the residence times of evolved volatiles in the reactor freeboard to be changed without altering. An investigation of msw gasification in a spout fluid bed reactor. Mixed plastic wastes pyrolysis in a fluidized bed reactor for. Catalytic pyrolysis of biomass in a fluidized bed reactor on.
Using a thermogravimetric analyser tga as a fixed bed and the tgfbr as a fluidized bed, the pyrolysis kinetics of olive kernels was studied. For practical design the predicted velocity is preferably. Temperature ramping 5 cmin was applied to the heating until a reactor temperature of 460 c was reached. Fluidised beds are used for several purposes, such as fluidized bed reactors types of chemical reactors, solids separation, fluid catalytic cracking, fluidized bed combustion, heat or mass transfer or interface modification, such as applying a coating onto solid items. Design of a fluidized bed reactor for biomass pyrolysis. Especially for reactor design it is necessary to clarify to what extent experimental kinetic data gained at low heating rates can be applied to heating conditions like in a fluidized bed or in an. The bubbling fluidized bed reactor was used in the simulation, in which the advantages of a good mixture is presented, one which provides high rates of mass and heat transfer. Biooil production from biomass by flash pyrolysis in a. Design, modelling and construction of a scalable dual. Numerical simulation of biomass fast pyrolysis in fluidized bed and auger reactors soroush aramideh iowa state university follow this and additional works at.
Many industrial plants prefer this method which has high efficiency. O to arrive at our fluidized bed design equation for a first order reaction, we simply express both the concentration of a in the emulsion. Fast pyrolysis of cotton stalk, obtained from agriculture. Fluidizedbed reactors appear to be popular for fast pyrolysis as they. Bubbling fluidized bed reactor chemical engineering world. The present work concerns with cfd modelling of biomass fast pyrolysis in a fluidised bed reactor. Design, modelling and construction of a scalable dual fluidised bed reactor for the pyrolysis of biomass. Bringing together industrial and academic expertise in fluidized and fixed bed systems. Char yields increased for the fluid bed reactor above 515c, and also in the ablative pyrolysis reactor. In the small fluid bed used for this work, with a char holdup of up to 5 vol % or 0. The pyrolysis of biomass is a thermochemical process in which woody biomass is converted to several highvalue products such as biooil, biochar and syngas. Design and operation of a low cost biooil fast pyrolysis from sugarcane bagasse on circulating fluidized bed reactor in a pilot plant.
Kulkarni chemical engineering and process development division, national chemical laboratory, india keywords. Both bfb and cfb can meet most of the required operating conditions for fast pyrolysis high heat transfer, small biomass particles, although the operation of the cfb in plug flow mode is favoured since it can satisfy the extra condition of short and strictly. Modeling of pyrolysis and gasification of biomass in. Dual fluidizedbed design for the fast pyrolysis of biomass. The system consists of a continuous fluidized bed reactor 0. Pyrolysis reactors are mostly modelled in laboratory equipment or in pilot plant for the time being in order to aid understanding of the principal factors controlling the processes and for finding the optimal parameters to obtain recycled products of required quality and quantity at the same time. Design aspects of industrial fluidized bed reactors.
Catalytic pyrolysis of biomass in a fluidized bed reactor. Dual fluidized bed design the physical design of the dual fluidized bed system including the solid transfer mechanism that was chosen for the investigation is shown in figure 2. Operating parameters for the circulating fluidized bed cfb. Activated carbon from coconut shell using fluidized bed. The system employs three separate but interconnected fluidized bed reactors. The heattransfer rate in a fluidized bed can be five to ten times greater than that in a packed bed reactor. The pyrolysis of bulk feed requires the use of some alternative pyrolysis reactors other than the conventional fluidized bed reactors used in the fast pyrolysis of biomass.
Fluidised bed pyrolysis of olive kernel biomass in a thermogravimetric. Fluidized bed reactors incorporate a bed of granular material, typically sand or. A crossover arm, fed by gravity, moves sand and char. In particular, the process of pyrolysis carried out in fluidized bed reactors appears one of the most attractive being able to obtain sufficiently high yields of valuable products 1,2,7. Design and construction of a smallscale fixedbed reactor. Circulating fluid bed reactor reactors ablative pyrolysis. Largescale pyrolysis oil technical report production.
Mod01 lec18 fluidized bed reactor design i youtube. The bubbling fluidized bed is doubtless the foremost standard reactor for quick shift. The gassolid flow that occurs in this reactor was described through mass, energy, momentum, and chemical species balances. Fast pyrolysis of biomass in a fluidized bed reactor. Even for the most extreme exothermic reactions, a fluidized bed can maintain an isothermal profile within a few degrees. The fluidized bed pyrolysis process possesses highly excellent mass transfer characteristics as it offers an effective and highly positive means of heating of finely chopped biomass in a rapid manner to achieve the pyrolysis temperature to the desired level. An indirectfired rotary kiln was suggested to be a suitable choice subject to the need for a better thermal efficiency. A thesis submitted for the degree of doctor of philosophy at the university of london november 1999 department of chemical engineering torrington place london wc 1 e 7je.
The dual fluidized bed reactor is a recirculating system in which one half of the unit operates as a steam pyrolysis device for biomass. Fluidized bed pyrolysis of plastic wastes request pdf. University of groningen particle transport in fluidized beds. Moving particles, especially small particles, can transport heat much more efficiently than gas alone. Design, simulation analysis and performance evaluation of a fluidized bed reactor for the pyrolysis of biomass article pdf available august 2018 with 280 reads how we measure reads.