scholarly journals Modelling and Simulation of a Fluidized Bed Reactor for Minimum Ammonium Nitrate and Reduction of NOx Emissions

2018 ◽  
Vol 20 (1) ◽  
pp. 8 ◽  
Author(s):  
Aysar Talib Jarullah
Keyword(s):  
Ammonium Nitrate ◽  
Fluidized Bed ◽  
Chemical Engineering ◽  
Optimization Technique ◽  
Fluidized Bed Reactor ◽  
Operating Conditions ◽  
Optimal Operating ◽  
Two Phase ◽  
Zone Length ◽  
Engineering Research

<p>Due to the environmental legislations related to the nitrates and their emissions, thermal decomposition of ammonium nitrate (AN) in a fluidized reactor (FR) is regarded one of the most reasonable chemical-free disposal process for an aqueous waste nitrate stream. Therefore, the present study is aimed to improve a mathematical model based on experiments (from the literature) for enhancing the design of such reactor in an environmentally friendly manner. Where, the optimal kinetic parameters of the relevant reactions are firstly obtained employing the optimization technique keeping in mind the goal to construct the model with high exactness. Such design factors are then utilized for the purpose of getting the optimal operating conditions of fluidized bed reactor (FBR) achieving the main target of this process with ammonium nitrate-free content (Nil) at the end of the reactor in addition to reducing the NO<em><sub>x</sub></em><em> </em>emissions. The model is based on the two-phase theory of a FBR with predicting the concentration behavior along the reaction zone length for all components in the emulsion and bubble phases in addition to the temperature profile of the gas phase. New results related to output conversion of ammonium nitrate as well as NO content at the optimal operating conditions has been obtained in comparison with those reported in the literature.</p><p>Chemical Engineering Research Bulletin 20(2018) 8-18</p>

Characterization of a limestone in a batch fluidized bed reactor for sulfur retention under oxy-fuel operating conditions

2011 ◽  
Vol 5 (5) ◽  
pp. 1190-1198 ◽  
Author(s):  
Luis F. de Diego ◽  
Margarita de las Obras-Loscertales ◽  
Francisco García-Labiano ◽  
Aránzazu Rufas ◽  
Alberto Abad ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Operating Conditions

Liquid-Solid Coupling Characteristics in the Fluidized Bed Evaporator for Tobacco Refined Liquid

2014 ◽  
Vol 686 ◽  
pp. 522-528
Author(s):  
Feng Lan Wang ◽  
Yuan Jun Yao ◽  
Fa Yun Gong ◽  
Fang Ping Ye ◽  
Wen Jie Qi
Keyword(s):  
Fluidized Bed ◽  
Flow Characteristics ◽  
Operating Conditions ◽  
Maximum Speed ◽  
Force Model ◽  
Liquid Density ◽  
Two Phase ◽  
Viscous Term ◽  
Inert Particles ◽  
Coupling Characteristics

Consider a two-phase liquid-solid coupling effect, using Euler - Euler two-fluid model is solved using standard viscous term with k-ε model and the velocity pressure coupling a simple algorithm to simulate liquid-solid two-phase flow characteristics of the fluid flow method bed, the applicability of the model to assess the drag. Different effects of a two-stage flow characteristics of fluidized bed flow characteristics, fluid and operating conditions affect the physical properties of the paper. We found from the simulation is the use of different drag coefficient models will greatly affect the results, which drag force model Syamlal - O'Brien is more suited to study the coupling characteristics of liquid flow in a fluidized bed of solid than Gidaspow. And velocity of the inert particles increase with the viscosity of the liquid increase. Further, the maximum speed of the inert particles in a fluidized bed by a central, which means the settling velocity in the fluidized bed of inert particles is the slowest; increasing liquid density and lead to increased speed of the inert particles; volume of the inert particles Score changes can also affect the speed of the particle velocity distribution, and there is no linear relationship.

Simulation Study of Gas-Solid Macro-Mixing Characterization in Small Fixed-Fluidized Bed Reactor

2011 ◽  
Vol 236-238 ◽  
pp. 1537-1545
Author(s):  
Wen Jing Liu ◽  
Hui Zhao ◽  
Chao He Yang ◽  
Hong Hong Shan
Keyword(s):  
Fluidized Bed ◽  
Raw Materials ◽  
Fluid Model ◽  
Structural Parameters ◽  
Flow Behavior ◽  
Fluidized Bed Reactor ◽  
Operating Conditions ◽  
Laboratory Evaluation ◽  
Two Fluid Model ◽  
Two Fluid

In fixed-fluidized bed reactor, laboratory evaluation of different catalyst, raw materials and process parameters can be implemented, so it has wide applications in the refining process. In this study, we focused on small fixed-fluidized bed reactor, using Eulerian-Eulerian two-fluid model, simulated the gas-solid flow behavior in it. Gas residence time distribution was measured in order to characterize macro-mixing. At the same time, by changing the reactor structure and operating conditions, we studied their effects on gas-solid macro-mixing characterization. The results show that the effects of structural parameters are larger than operating conditions, and different parameters have different effects. Different parameters can be adjusted to change the gas-solid macro-mixing characterization in small fixed-fluidized bed reactor. Therefore, the small fixed-fluidized bed reactor can provide better results in more application areas.

Modelling of Fischer-Tropsch Synthesis in a Fluidized Bed Reactor

2012 ◽  
Vol 586 ◽  
pp. 274-281
Author(s):  
Mohammad Kazemeini ◽  
Reza Maleki ◽  
Moslem Fattahi
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Natural Gas ◽  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Product Distribution ◽  
Operating Conditions ◽  
Distribution Model ◽  
Fischer Tropsch ◽  
Respective Rate

The FT reaction involves the conversion of syngas which is derived from natural gas or coal to different kinds of products according to the operating conditions and the type of the catalyst. In other words, it is a practical way to convert solid fuel (coal) and natural gas to various hydrocarbons (C1-C60) and oxygenates such as alkanes, alkenes etc. The main products of the reaction are naphtha and gasoline. This paper deals with developing a proper product distribution model for FT process using the appropriate kinetic model, optimizing the respective rate constants while applying them in product distribution equations. The results revealed only 8.09% deviations from the olefin experimental data and 10.27% deviations from the paraffin experimental data being acceptable when compared with previous open literature data.

Machine Learning-Based Model for Optimal Operating Conditions of Thermosyphons for Electronic Cooling Applications

2021 ◽  
Author(s):  
John Kim ◽  
Raffaele L. Amalfi
Keyword(s):  
Machine Learning ◽  
Thermal Performance ◽  
Cooling System ◽  
Electronic Cooling ◽  
Operating Conditions ◽  
Complex Nature ◽  
System Control ◽  
Optimal Operating ◽  
Two Phase ◽  
Wide Range

Abstract Two-phase cooling systems based on the thermosyphon operating principle exhibit excellent heat transfer performance, reliability, and flexibility, therefore can be applied to overcome thermal challenges in a wide range of electronic cooling applications and deployment scenarios. However, extremely complex nature of two-phase flow physics involving flow patterns and phase transitions has been the major challenge for technology adoption in industry. This paper demonstrates a machine learning (ML) based model for evaluating the thermal performance and refrigerant mass flow rate, of a thermosyphon cooling system for telecom equipment. Unlike conventional laboratory approach that requires numerous sensors attached to a cooling system to capture their thermal performance, the new model requires a minimum number of sensors to monitor the health of a thermal management solution. Using the proposed model, a system control module can be further developed which could identify optimal operating parameters in real-time under dynamically changing heat load conditions and actively maintain safety and thermal requirements.

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