Pdf computational fluid dynamics modeling of trickle bed reactor subhasish mitra academia. Their application areas, the traditional approach to their design and scaleup, and some commonly encountered problems in practice are discussed. Hence, in the design of mixed phase downflow fixed bed reactors both. It is most widely used three phase reactor for different purposes. Trickle bed reactors provide the flexibility of operating at extreme conditions of high temperatures and high pressures. High performance fixed bed trickle bed without the trickle fixed bed with catalyst particles typically less than 100um use of high pressure pumps not gravity control of hydrogen injection rate tight residence time distribution suitable for complex pharmaceutical products however traditionally challenging scale up. In this work, three different aspects in design of tbr have been addressed using cfd simulations. Engineering aspects of trickle bed reactors rm koros. Slurry reactors description of use of slurry reactors.
A tricklebed reactor is a continuous, packed bed reactor where the liquid flows down through a packing medium. This book provides a hybrid methodology for engineering of trickle bed reactors by integrating conventional reaction engineering models with stateoftheart computational flow models. In a trickle bed reactor the liquid and gas move over bed. The liquid phase wastewater is introduced from the top of the reactor and trickle over the wetted packing. A new fluid dynamic model has been developed predicting the static liquid holdup in trickle bed reactors based on liquidsolid physical and local structural properties of a packed bed. Pdf computational fluid dynamics modeling of trickle bed. Shah 1979 has summarized the advantages of trickle. The catalyst is usually in the form of porous pellets 3.
Trickle bed reactor the material presented in this example is meant to serve as an introduction to trickle bed reactors. Multistage leach bed reactor mslbr system proposed in the current study is capable of handling hscm of up to 90% ts. The trickle bed reactor adopts the technical scheme that the trickle bed reactor comprises an inlet orifice, a reactor shell. The earliest antecedent probably was the socalled trickling filter which has long been. Tricklebed reactors are used primarily in the petroleum industry for hydrocracking, hydrodesulfurization, and hydrodenitrogenation. A dissertation in chemical engineering submitted to the graduate faculty of texas tech university in partial fulfillment of the requirements for the degree of. In this system, hydrolysis and methanogenesis are carried out in separate reactors for the optimization of each stage. They must ensure good distribution of both the vapor and the liquid, without channeling of either phase towler, 2012. Knoechelmann2 1nuclear energy department, federal university of pernambuco ufpe, phone 081 32718251, fax 081 32718250, av. A tricklebed reactor tbr is a chemical reactor that uses the downward movement of a liquid and the downward cocurrent or upward countercurrent movement of gas over a packed bed of particles. Trickle bed reactor an overview sciencedirect topics.
The physical and chemical phenomena as well as operation characteristics inside trickle bed reactors have been extensively studied in smallscale reactors but very little data of industrialscale reactors. Pdf the present study deals with a multiple reaction system in both gas and liquid phases considering the effect of gasliquid mass transfer. Liquid spreading in a trickle bed reactor is characterized through liquid holdup and pressure drop measurements for different particle sizes, and liquid and gas flow rates. Department of chemical engineering university of pretoria degree. Schnitzlein, chair of chemical reaction engineering, brandenburg university of technology, 03046 cottbus, germany. Effect of loading, particle size and gas adsorption. A trickle bed reactor is a type of threephase reactors in which a gas and a liquid phase cocurrently flow downward over a packed bed of catalyst particles. Master of engineering chemical engineering abstract hydrodynamic multiplicity in the trickle flow, or low interaction, regime is a well documented phenomenon. Solidliquid mass transfer in trickle bed reactors author.
A trickle bed reactor is a continuous, packed bed reactor where the liquid flows down through a packing medium. Trickle bed reactors are widely used in the field of chemical and petroleum refining industry. Overall, the trickle bed is simpler, the slurry reactors usually has a high reaction rate and the fluidized bed is. It is considered to be the simplest reactor type for performing catalytic reactions where a gas and liquid normally both reagents are present in the reactor and accordingly it is extensively used.
Request pdf trickle bed reactors this book provides a hybrid methodology for engineering of trickle bed reactors by integrating conventional reaction. So the trickle bed reactor im talking about is r201 in the pfd. Tricklebed reactors tbrs, which accommodate the flow of gas and liquid phases through packed beds of catalysts, host a variety of gasliquidsolid catalytic reactions, particularly in the. Evaluation of liquidsolid contacting in trickle bed reactors by tracer methods. The reactor consists of a vessel packed with the packing material such as pvc shredding, gravels, sand, coconut shell, cotton, iodine. Cfd modeling of trickle bed reactors simulated results 0. Bentuk partikel katalis yang digunakan reaktor trickle bed memberikan performa yang lebih baik dalam pengontakan gasliquid solid dengan memberikan efisiensi yang tinggi dibandingkan oleh reactor lain seperti stirred slurry reactors yang memberikan keterbatasan pengaplikasisan pada system reaksi yang cepat membutuhkan muatan katalis yang rendah dengan tekanan operasi rendah dan. Most commercial trickle bed reactors operate adiabatically at high temperatures. Mohit kumar 2016cl03 hitesh babu 2016cl08 chemical department, mnnit allahabad introduction tricklebed reactor is a reactor in which a liquid and a gas phase flow cocurrently downward on stationary catalyst packing while the reaction takes place. As far as tbrs numerical modelling is concerned, many approaches have been considered hitherto to solve for the twophase flow in trickle bed reactors. Other workedout trickle bed example problems can be found in an article by ramachandran and chaudhari 6. Syngas can move either in a downward cocurrent or upward countercurrent direction. Trickle bed reactors are packed bed reactors in which the gas phase is a continuous phase.
Effluent treatment plant using modified version of trickle. Trickle bed reactors general information trickle bed reactors are solidliquidgas contacting devices wherein a liquid stream flows downward over a bed of catalyst with pressure difference serving as the driving force. Compared to cstr, trickle bed reactors do not require mechanical agitation, thus the energy consumption of the trickle bed reactors can be lower. Trickle bed reactors dont have this problem and this is a big advantage of trickle bed reactor. Other commercial applications of tricklebed reactors can be found in the. Introduction the term trickle bed is used here to mean a reactor in which a liquid phase and a gas phase flow concurrently downward through a fixed bed of catalyst particles while reaction takes place. The term trickle literally refers to characteristic. The content may be used in several ways and at various stages. Im accustomed to calling that type of reactor is a fixed catalyst bed that is fed liquid reactants that combine with a recirculated gaseous phase to form either a condensable vapor product or a liquid product within the. Construction of the trickle bed reactor is very simple as there are no moving parts.
This study investigates the interaction between liquid. Hydrolysis is carried out in a trickle flow leach bed reactor tflbr and methanogenesis is carried out in a. The invention relates to a trickle bed reactor, which mainly aims at solving the problem that the uneven liquidgas distribution of the trickle bed reactor in the prior art results in the bad trickling effect of the reactor and low efficiency of the catalytic reaction. Pdf trickle bed reactor simulation using a process simulator. In addition, the hyrodesulfurication of a hydrocarbon in a trickle bed reactor is given in detail by tarhan 7. Trickle bed reactors are used when all three phases are involved in the reaction. Multi bed downflow trickle bed reactors tbrs find enormous applications in petroleum refinery, petrochemicals industry and effluent treatment. Design of trickle bed reactors based on hydrodynamic. Oxidation of 5hydroxymethylfurfural hmf to 2,5furandicarboxylic acid fdca was carried out over rual2o3 using o2 aqueous alkaline solutions in a trickle bed reactor. Cfd modeling of radial spreading of flow in tricklebed reactors due to mechanical and capillary dispersion, chemical engineering science, 64, 207218.
The fluid flows over catalyst particles and forms fine films, rivulets or droplets. Modelling of trickle bed reactor for the catalytic wet air. A fundamental division of threephase reactors may be made by whether the solid phase is present as a. Tricklebed reactors is most widely used type of threephase reactors. Modeling, control, and optimization of fixed bed reactors by kishor g. Effect of partial wetting on liquidsolid mass transfer in. It is estimated that a significant fraction of all the petroleum processed passes through a trickle bed reactor in one way or another.