scholarly journals Modelling of Jatropha Oil Hydrocracking in a Trickle-Bed Reactor to Produce Green Fuel

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yuswan Muharam ◽  
Dianursanti ◽  
Andrey Sapati Wirya
Keyword(s):  
Heat Transfer ◽  
Optimum Condition ◽  
Molar Ratio ◽  
Inlet Temperature ◽  
Jatropha Oil ◽  
Gas Velocity ◽  
Trickle Bed Reactor ◽  
Green Fuel ◽  
Feed Molar Ratio ◽  
Good Heat

Trickle-bed reactor (TBR) modelling to produce green fuel via hydrocracking of jatropha oil using silica-alumina-supported Ni-W catalysts was performed in this research. The objectives of this study are to obtain a TBR with good heat transfer and the optimum condition for high purities of products. A two-dimensional axisymmetric model with a diameter of 0.1 m and a length of 10 m was used as a representative of the actual TBR system. Heterogeneous phenomenological models were developed considering mass, energy, and momentum transfers. The optimisation was conducted to obtain the highest green fuel purity by varying catalyst particle diameter, inlet gas velocity, feed molar ratio, and inlet temperature. The simulation shows that a TBR with an aspect ratio of 100 has achieved a good heat transfer. The diesel purity reaches 44.22% at 420°C, kerosene purity reaches 21.39% at 500°C, and naphtha purity reaches 25.30% at 500°C. The optimum condition is reached at the catalyst diameter of 1 mm, the inlet gas velocity of 1 cm/s, the feed molar ratio of 105.5, and the inlet temperature at 500°C with the green fuel purity of 69.4%.

Effects of Process Factors on Carbon Dioxide Reforming of Methane over Ni/SBA-15 Catalyst

2017 ◽  
Vol 68 (10) ◽  
pp. 2325-2328
Author(s):  
Cristina Orbeci ◽  
Oana Cristina Parvulescu ◽  
Elena Acceleanu ◽  
Tanase Dobre
Keyword(s):  
Carbon Dioxide ◽  
Operating Temperature ◽  
Space Velocity ◽  
Molar Ratio ◽  
Co2 Conversion ◽  
Gas Velocity ◽  
Experimental Conditions ◽  
Process Factors ◽  
Independent Parameters ◽  
Feed Molar Ratio

The process of CO2 reformation of CH4 was conducted over a 5% Ni/SBA-15 catalyst under various experimental conditions. Operating temperature (600-750 �C), gas hourly space velocity (4000-12000 hr-1), and CO2/CH4 feed molar ratio (0.67-1.50) were selected as independent parameters (factors). Process performances were evaluated as conversions of CH4 (21.1-79.6%) and CO2 (42.4-98.7%) as well as H2/CO product molar ratio (0.573-0.992). All process performances were enhanced at higher levels of temperature and low values of gas velocity. An increase in feed molar ratio has determined a significant increase in CH4 conversion and a slighter decrease in CO2 conversion and H2/CO molar ratio. A statistical model based on a 23 factorial plan was used to predict the process performances depending on its factors.

scholarly journals Application of Tin(II) Chloride Catalyst for High FFA Jatropha Oil Esterification in Continuous Reactive Distillation Column

2016 ◽  
Vol 11 (1) ◽  
pp. 66 ◽  
Author(s):  
Ratna Dewi Kusumaningtyas ◽  
Imam Novrizal Aji ◽  
Hadiyanto Hadiyanto ◽  
Arief Budiman
Keyword(s):  
Reaction Time ◽  
Optimum Condition ◽  
Distillation Column ◽  
Reactive Distillation ◽  
Acid Catalyst ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Jatropha Oil ◽  
Chloride Catalyst

<p>The application of heterogeneous solid acid catalysts in biodiesel production has become popular and gained significant attention over the last few years. It is since these types of catalysts hold the benefits in terms of easy separation from the product, reusability of the catalyst, high selectivity of the reaction. They are also considered sustainable and powerful particularly in organic synthesis. This work studied the use of tin(II) chloride as solid Lewis acid catalyst to promote the esterification reaction of high Free Fatty Acid (FFA) jatropha oil in continuous reactive distillation column. To obtain the optimum condition, the influences of reaction time, molar ratio of the reactant, and catalyst were investigated. It was revealed that the optimum condition was achieved at the molar ratio of methanol to FFA at 1:60, catalyst concentration of 5%, and reaction temperature of 60°C with the reaction conversion of 90%. This result was significantly superior to the identical reaction performed using batch reactor. The esterification of high FFA jatropha oil using reactive distillation in the presence of tin(II) chloride provided higher conversion than that of Amberlyst-15 heterogeneous catalyst and was comparable to that of homogenous sulfuric acid catalyst, which showed 30 and 94.71% conversion, respectively. The esterification reaction of high FFA jatropha oil was subsequently followed by transesterification reaction for the completion of the biodiesel production. Transesterification was carried out at 60 °C, molar ratio of methanol to oil of 1:6, NaOH catalyst of 1%, and reaction time of one hour. The jatropha biodiesel product resulted from this two steps process could satisfy the ASTM and Indonesian biodiesel standard in terms of ester content (97.79 %), density, and viscosity. Copyright © 2016 BCREC GROUP. All rights reserved</p><p><em>Received: 10<sup>th</sup> November 2015; Revised: 4<sup>th</sup> February 2016; Accepted: 4<sup>th</sup> February 2016</em></p><p><strong>How to Cite</strong>: Kusumaningtyas, R.D., Aji, I.N., Hadiyanto, H., Budiman, A. (2016). Application of Tin(II) Chloride Catalyst for High FFA Jatropha Oil Esterification in Continuous Reactive Distillation Column. <em>Bulletin of Chemical Reaction Engineering &amp; Catalysis</em>, 11 (1): 66-74. (doi:10.9767/bcrec.11.1.417.66-74)</p><p><strong>Permalink/DOI</strong>: <a href="http://dx.doi.org/10.9767/bcrec.11.1.417.66-74">http://dx.doi.org/10.9767/bcrec.11.1.417.66-74</a></p>

Efficient Micromixing for Continuous Biodiesel Production from Jatropha Oil

2018 ◽  
Vol 9 (1) ◽  
pp. 133-139
Author(s):  
Waleed S. Mohammed ◽  
Ahmed H. El-Shazly ◽  
Marwa F. Elkady ◽  
Masahiro Ohshima
Keyword(s):  
Methyl Esters ◽  
Continuous Process ◽  
Sol Gel ◽  
Average Diameter ◽  
Biodiesel Production ◽  
High Mass ◽  
Molar Ratio ◽  
Jatropha Oil ◽  
Energy Deficiency ◽  
Gel Preparation

Introduction: The utilization of biodiesel as an alternative fuel is turning out to be progressively famous these days because of worldwide energy deficiency. The enthusiasm for utilizing Jatropha as a non-edible oil feedstock is quickly developing. The performance of the base catalyzed methanolysis reaction could be improved by a continuous process through a microreactor in view of the high mass transfer coefficient of this technique. Materials & Methods: Nanozirconium tungstovanadate, which was synthetized using sol-gel preparation method, was utilized in a complementary step for biodiesel production process. The prepared material has an average diameter of 0.066 &µm. Results: First, the NaOH catalyzed methanolysis of Jatropha oil was investigated in a continuous microreactor, and the efficient mixing over different mixers and its impact on the biodiesel yield were studied under varied conditions. Second, the effect of adding the nanocatalyst as a second stage was investigated. Conclusion: The maximum percentage of produced methyl esters from Jatropha oil was 98.1% using a methanol/Jatropha oil molar ratio of 11 within 94 s using 1% NaOH at 60 &°C. The same maximum conversion ratio was recorded with the nanocatalyst via only 0.3% NaOH.

scholarly journals Energy and Exergy Efficiency Analysis of Fluid Flow and Heat Transfer in Sinter Vertical Cooler

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4522
Author(s):  
Zude Cheng ◽  
Haitao Wang ◽  
Junsheng Feng ◽  
Yongfang Xia ◽  
Hui Dong
Keyword(s):  
Heat Transfer ◽  
Energy Efficiency ◽  
Fluid Flow ◽  
Waste Heat ◽  
Exergy Efficiency ◽  
Inlet Temperature ◽  
Operational Parameters ◽  
Flow And Heat Transfer ◽  
Maximum Value ◽  
Energy And Exergy

In order to fully understand the energy and exergy transfer processes in sinter vertical coolers, a simulation model of the fluid flow and heat transfer in a vertical cooler was established, and energy and exergy efficiency analyses of the gas–solid heat transfer in a vertical cooler were conducted in detail. Based on the calculation method of the whole working condition, the suitable operational parameters of the vertical cooler were obtained by setting the net exergy efficiency in the vertical cooler as the indicator function. The results show that both the quantity of sinter waste heat recovery (SWHR) and energy efficiency increased as the air flow rate (AFR) increased, and they decreased as the air inlet temperature (AIT) increased. The increase in the sinter inlet temperature (SIT) resulted in an increase in the quantity of SWHR and a decrease in energy efficiency. The air net exergy had the maximum value as the AFR increased, and it only increased monotonically as the SIT and AIT increased. The net exergy efficiency reached the maximum value as the AFR and AIT increased, and the increase in the SIT only resulted in a decrease in the net exergy efficiency. When the sinter annual production of a 360 m2 sintering machine was taken as the processing capacity of the vertical cooler, the suitable operational parameters of the vertical cooler were 190 kg/s for the AFR, and 353 K for the AIT.

Heat Transfer to Supercritical Water in Vertical Annular Channel and 3-Rod Bundle

2009 ◽  
Author(s):  
V. G. Razumovskiy ◽  
Eu. N. Pis’mennyy ◽  
A. Eu. Koloskov ◽  
I. L. Pioro
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Supercritical Water ◽  
Annular Channel ◽  
Heat Fluxes ◽  
Inlet Temperature ◽  
Outlet Temperature ◽  
Rod Bundle ◽  
Temperature Regimes ◽  
Outside Diameter

The results of heat transfer to supercritical water flowing upward in a vertical annular channel (1-rod channel) and tight 3-rod bundle consisting of the tubes of 5.2-mm outside diameter and 485-mm heated length are presented. The heat-transfer data were obtained at pressures of 22.5, 24.5, and 27.5 MPa, mass flux within the range from 800 to 3000 kg/m2·s, inlet temperature from 125 to 352°C, outlet temperature up to 372°C and heat flux up to 4.6 MW/m2 (heat flux rate up to 2.5 kJ/kg). Temperature regimes of the annular channel and 3-rod bundle were stable and easily reproducible within the whole range of the mass and heat fluxes, even when a deteriorated heat transfer took place. The data resulted from the study could be applicable for a reference estimation of heat transfer in future designs of fuel bundles.

Heat transfer characteristic modelling and the effect of operating conditions on re-cooled cycle for a scramjet

2011 ◽  
Vol 115 (1164) ◽  
pp. 83-90 ◽  
Author(s):  
W. Bao ◽  
J. Qin ◽  
W. X. Zhou
Keyword(s):  
Heat Transfer ◽  
Heat Sink ◽  
Transfer Characteristic ◽  
Cooling Capacity ◽  
Sensitivity Study ◽  
Performance Model ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Fuel Flow ◽  
Temperature And Pressure

Abstract A re-cooled cycle has been proposed for a regeneratively cooled scramjet to reduce the hydrogen fuel flow for cooling. Upon the completion of the first cooling, fuel can be used for secondary cooling by transferring the enthalpy from fuel to work. Fuel heat sink (cooling capacity) is thus repeatedly used and fuel heat sink is indirectly increased. Instead of carrying excess fuel for cooling or seeking for any new coolant, the cooling fuel flow is reduced, and fuel onboard is adequate to satisfy the cooling requirement for the whole hypersonic vehicle. A performance model considering flow and heat transfer is build. A model sensitivity study of inlet temperature and pressure reveals that, for given exterior heating condition and cooling panel size, fuel heat sink can be obviously increased at moderate inlet temperature and pressure. Simultaneously the low-temperature heat transfer deterioration and Mach number constrains can also be avoided.

IMPROVING THE FILM COOLING PERFORMANCE OF A TURBINE ENDWALL WITH MULTI-FIDELITY MODELING CONSIDERING CONJUGATE HEAT TRANSFER

2021 ◽  
pp. 1-20
Author(s):  
Hongyan Bu ◽  
Yufeng Yang ◽  
Liming Song ◽  
Jun Li
Keyword(s):  
Heat Transfer ◽  
Design Optimization ◽  
Film Cooling ◽  
Conjugate Heat Transfer ◽  
Inlet Temperature ◽  
High Fidelity ◽  
Cooling Performance ◽  
Fine Mesh ◽  
Film Cooling Holes ◽  
Component Temperature

Abstract The gas turbine endwall is bearing extreme thermal loads with the rapid increase of turbine inlet temperature. Therefore, the effective cooling of turbine endwalls is of vital importance for the safe operation of turbines. In the design of endwall cooling layouts, numerical simulations based on conjugate heat transfer (CHT) are drawing more attention as the component temperature can be predicted directly. However, the computation cost of high-fidelity CHT analysis can be high and even prohibitive especially when there are many cases to evaluate such as in the design optimization of cooling layout. In this study, we established a multi-fidelity framework in which the data of low-fidelity CHT analysis was incorporated to help the building of a model that predicts the result of high-fidelity simulation. Based upon this framework, multi-fidelity design optimization of a validated numerical turbine endwall model was carried out. The high and low fidelity data were obtained from the computation of fine mesh and coarse mesh respectively. In the optimization, the positions of the film cooling holes were parameterized and controlled by a shape function. With the help of multi-fidelity modeling and sequentially evaluated designs, the cooling performance of the model endwall was improved efficiently.

A Method of Solving Three Temperature Problem of Turbine With Adiabatic Wall Temperature

2021 ◽  
Author(s):  
Zeyu Wu ◽  
Xiang Luo ◽  
Jianqin Zhu ◽  
Zhe Zhang ◽  
Jiahua Liu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Reynolds Number ◽  
Wall Temperature ◽  
Reference Temperature ◽  
Inlet Temperature ◽  
Adiabatic Wall ◽  
Rotating Cavity ◽  
Temperature Problem ◽  
Turbulence Parameters

Abstract The aeroengine turbine cavity with pre-swirl structure makes the turbine component obtain better cooling effect, but the complex design of inlet and outlet makes it difficult to determine the heat transfer reference temperature of turbine disk. For the pre-swirl structure with two air intakes, the driving temperature difference of heat transfer between disk and cooling air cannot be determined either in theory or in test, which is usually called three-temperature problem. In this paper, the three-temperature problem of a rotating cavity with two cross inlets are studied by means of experiment and numerical simulation. By substituting the adiabatic wall temperature for the inlet temperature and summarizing its variation law, the problem of selecting the reference temperature of the multi-inlet cavity can be solved. The results show that the distribution of the adiabatic wall temperature is divided into the high jet area and the low inflow area, which are mainly affected by the turbulence parameters λT, the rotating Reynolds number Reω, the high inlet temperature Tf,H* and the low radius inlet temperature Tf,L* of the inflow, while the partition position rd can be considered only related to the turbulence parameters λT and the rotating Reynolds number Reω of the inflow. In this paper, based on the analysis of the numerical simulation results, the calculation formulas of the partition position rd and the adiabatic wall temperature distribution are obtained. The results show that the method of experiment combined with adiabatic wall temperature zone simulation can effectively solve the three-temperature problem of rotating cavity.

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