scholarly journals Simulation Study to Investigate the Effects of Operational Conditions on Methylcyclohexane Dehydrogenation for Hydrogen Production

Energies ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 206 ◽  
Author(s):  
Muhammad Haris Hamayun ◽  
Ibrahim M. Maafa ◽  
Murid Hussain ◽  
Rabya Aslam
Keyword(s):  
Simulation Study ◽  
Clean Energy ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Ambient Conditions ◽  
Feed Mixture ◽  
Operational Conditions ◽  
Hydrogen Addition ◽  
Aspen Hysys ◽  
Methylcyclohexane Dehydrogenation

In the recent era, hydrogen has gained immense consideration as a clean-energy carrier. Its storage is, however, still the main hurdle in the implementation of a hydrogen-based clean economy. Liquid organic hydrogen carriers (LOHCs) are a potential option for hydrogen storage in ambient conditions, and can contribute to the clean-fuel concept in the future. In the present work, a parametric and simulation study was carried out for the storage and release of hydrogen for the methylcyclohexane toluene system. In particular, the methylcyclohexane dehydrogenation reaction is investigated over six potential catalysts for the temperature range of 300–450 °C and a pressure range of 1–3 bar to select the best catalyst under optimum operating conditions. Moreover, the effects of hydrogen addition in the feed mixture, and byproduct yield, are also studied as functions of operating conditions. The best catalyst selected for the process is 1 wt. % Pt/γ-Al2O3. The optimum operating conditions selected for the dehydrogenation process are 360 °C and 1.8 bar. Hydrogen addition in the feed reduces the percentage of methylcyclohexane conversion but is required to enhance the catalyst’s stability. Aspen HYSYS v. 9.0 (AspenTech, Lahore, Pakistan) has been used to carry out the simulation study.

scholarly journals Performance Analysis of the Perhydro-Dibenzyl-Toluene Dehydrogenation System—A Simulation Study

2021 ◽  
Vol 13 (11) ◽  
pp. 6490
Author(s):  
Farea Asif ◽  
Muhammad Haris Hamayun ◽  
Murid Hussain ◽  
Arif Hussain ◽  
Ibrahim M. Maafa ◽  
...  
Keyword(s):  
Exergy Analysis ◽  
Process Integration ◽  
Operating Conditions ◽  
Energy Resources ◽  
Optimum Operating ◽  
Operational Conditions ◽  
Aspen Hysys ◽  
System A ◽  
Analysis Strategy ◽  
And Storage

The depletion of conventional energy resources has drawn the world’s attention towards the use of alternate energy resources, which are not only efficient but sustainable as well. For this purpose, hydrogen is considered the fuel of the future. Liquid organic hydrogen carriers (LOHCs) have proved themselves as a potential option for the release and storage of hydrogen. The present study is aimed to analyze the performance of the perhydro-dibenzyl-toluene (PDBT) dehydrogenation system, for the release of hydrogen, under various operational conditions, i.e., temperature range of 270–320 °C, pressure range of 1–3 bar, and various platinum/palladium-based catalysts. For the operational system, the optimum operating conditions selected are 320 °C and 2 bar, and 2 wt. % Pt/Al2O3 as a suitable catalyst. The configuration is analyzed based on exergy analysis i.e., % exergy efficiency, and exergy destruction rate (kW), and two optimization strategies are developed using principles of process integration. Based on exergy analysis, strategy # 2, where the product’s heat is utilized to preheat the feed, and utilities consumption is minimized, is selected as the most suitable option for the dehydrogenation system. The process is simulated and optimized using Aspen HYSYS® V10.

scholarly journals Test campaign of a ducted wind turbine in real operating conditions

2019 ◽  
Vol 113 ◽  
pp. 03005
Author(s):  
Enrico Valditerra ◽  
Massimo Rivarolo ◽  
Aristide F. Massardo ◽  
Marco Gualco
Keyword(s):  
Wind Turbine ◽  
Urban Areas ◽  
Energy Production ◽  
Electrical Energy ◽  
Clean Energy ◽  
Operating Conditions ◽  
Pollutant Emissions ◽  
Ambient Conditions ◽  
Wind Speeds ◽  
Electrical Energy Production

Wind turbine installation worldwide has increased at unrested pace, as it represents a 100% clean energy with zero CO2 and pollutant emissions. However, visual and acoustic impact of wind turbines is still a drawback, in particular in urban areas. This paper focuses on the performance evaluation of an innovative horizontal axis ducted wind turbine, installed in the harbour of Genova (Italy) in 2018: the turbine was designed in order to minimize visual and acoustic impacts and maximize electrical energy production, also during low wind speed periods. The preliminary study and experimental analyses, performed by the authors in a previous study, showed promising results in terms of energy production, compared to a traditional generator ( factor >2.5 on power output). In the present paper, the test campaign on a scaled-up prototype, installed in the urban area of Genova, is performed, with a twofold objective: (i) comparison of the ducted innovative turbine with a standard one, in order to verify the increase in energy production; (ii) analysis of the innovative turbine for different wind speeds and directions, evaluating the influence of ambient conditions on performance. Finally, based on the obtained results, an improved setup is proposed for the ducted wind turbine, in order to further increase energy production mitigating its visual impact.

scholarly journals Inorganic carbon removal from refinery wastewater by using TiO2/ZnO/Fenton photocatalyst

2018 ◽  
Vol 20 (2) ◽  
pp. 216-225
Keyword(s):  
Inorganic Carbon ◽  
Treatment Time ◽  
Removal Rate ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Refinery Wastewater ◽  
Operational Conditions ◽  
Operating Variables ◽  
Solar Photocatalyst ◽  
Quadratic Models

The aim of this study is to investigate the performance of the solar photocatalyst of TiO2/ZnO/Fenton process to treat the refinery wastewater and remove inorganic carbon (IC) which potentially toxic to human, aquatic and microorganism life. Central composite design with response surface methodology was used to evaluate the relationships between operating variables for TiO2 dosage, ZnO dosage, Fe2+ dosage, H2O2 dosage, and pH to identify the optimum operating conditions. Quadratic models for inorganic carbon (IC) removal and residual iron prove to be significant with low probabilities (<0.0001). The (IC) removal rates and residual iron correspond well with the predicted models. The maximum removal rate for IC and residual iron was 92.3% and 0.013, respectively at optimum operational conditions of a TiO2 dosage (0.3 g/l), ZnO dosage (0.58 g/l), Fe2+ dosage (0.02 g/l), H2O2 dosage (2.7 g/l), and pH (7). The treatment process achieved higher degradation efficiencies for IC and reduced the treatment time comparing with other related processes.

scholarly journals An Experimental Investigation and Aspen HYSYS Simulation of Waste Polystyrene Catalytic Cracking Process for the Gasoline Fuel Production

2021 ◽  
Vol 10 (4) ◽  
pp. 891-900
Author(s):  
Selvaganapathy Thambiyapillai ◽  
Muthuvelayudham Ramanujam
Keyword(s):  
Experimental Investigation ◽  
Fly Ash ◽  
Catalytic Cracking ◽  
Liquid Fuel ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Chemical Recycling ◽  
Aspen Hysys ◽  
Ms Analysis ◽  
Cracking Process

Plastic wastes are necessary to recycle due to their disposal issues around the world. They can be recycled through various techniques i.e., mechanical reprocessing, mechanical recycling, chemical recycling and incineration. Most recycling techniques are expensive and end up in producing low-grade products excluding chemical recycling; it is an eco-friendly way to deal with plastic waste. Catalytic cracking is one of the chemical recycling methods, for converting waste plastics into liquid fuel same as commercial fuels. An experimental investigation of polystyrene catalytic cracking process was conducted with impregnated fly ash catalyst and 88.4% of liquid product yield was found as a maximum at optimum operating conditions 425 ̊C and 60 min. The liquid fuel quality was analyzed using FTIR spectra analysis, GC/MS analysis and Physico-chemical property analysis. The GC/MS analysis shows that the fly ash cracking of polystyrene leads to the production of gasoline fuels within the hydrocarbon range of C3-C24, and the aliphatic and aromatic functional compounds were detected using FTIR analysis. Moreover, the Aspen Hysys simulation of polystyrene catalytic cracking was conducted in a pyrolytic reactor at 425 ̊C and at the end of the simulation, 93.6% of liquid fuel yield was predicted. It was inferred that the simulation model for the catalytic cracking is substantial to fit the experimental data in terms of liquid fuel conversion

Effects of Dynamic Operational Conditions on Thermal Infrared Imaging of Monocrystalline Silicon Photovoltaic Modules

2020 ◽  
Vol 143 (2) ◽  
Author(s):  
M. Vumbugwa ◽  
J. L. Crozier McCleland ◽  
E. E. van Dyk ◽  
F. J. Vorster
Keyword(s):  
Infrared Imaging ◽  
Short Circuit ◽  
Thermal Infrared ◽  
Climatic Conditions ◽  
High Irradiance ◽  
Operating Conditions ◽  
Ambient Conditions ◽  
Operational Conditions ◽  
Pv Modules ◽  
Electrical Loads

Abstract Photovoltaic (PV) modules installed in the field generate electrical power under different meteorological and operational conditions; therefore, maintenance of the modules is crucial for the longevity of the PV modules. Thermal infrared (TIR) imaging is a widely used monitoring technique for quality checks of PV modules in plants. It is ideally conducted on operational PV modules under steady ambient conditions; however, PV modules operate under dynamic climatic conditions which influence the overall operation of all solar cells and modules. The dynamic nature of thermal signatures was observed on TIR images when monocrystalline PV modules operated under varying electrical loads and irradiance. A change in operating conditions affected the level of current mismatch between cells since at high irradiance of about 1000 watts per square meter (W m−2) and while operating close to short circuit current at reduced load, the PV cells generated a higher current which led to significant current mismatch. This resulted in several abnormally hot cells being identified on TIR images. Under lower irradiance and larger electrical loads, fewer hot cells were observed and cracked cells (identified through Electroluminescence (EL)) appeared as good cells due to minimal current mismatch. The effectiveness of TIR imaging to reveal underperforming defective cells as hot cells depends on the operating conditions and can mislead decision-making when PV module maintenance is carried out. This work gives valuable information which can be of importance in improving the maintenance systems of PV modules when TIR imaging is conducted.

Evaluating photo-degradation of COD and TOC in petroleum refinery wastewater by using TiO2/ZnO photo-catalyst

2016 ◽  
Vol 74 (6) ◽  
pp. 1312-1325 ◽  
Author(s):  
Dheeaa al deen Atallah Aljuboury ◽  
Puganeshwary Palaniandy ◽  
Hamidi Bin Abdul Aziz ◽  
Shaik Feroz ◽  
Salem S. Abu Amr
Keyword(s):  
Reaction Time ◽  
Treatment Time ◽  
Removal Rate ◽  
Air Flow ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Removal Rates ◽  
Operational Conditions ◽  
Photo Catalyst

The aim of this study is to investigate the performance of combined solar photo-catalyst of titanium oxide/zinc oxide (TiO2/ZnO) with aeration processes to treat petroleum wastewater. Central composite design with response surface methodology was used to evaluate the relationships between operating variables for TiO2 dosage, ZnO dosage, air flow, pH, and reaction time to identify the optimum operating conditions. Quadratic models for chemical oxygen demand (COD) and total organic carbon (TOC) removals prove to be significant with low probabilities (&lt;0.0001). The obtained optimum conditions included a reaction time of 170 min, TiO2 dosage (0.5 g/L), ZnO dosage (0.54 g/L), air flow (4.3 L/min), and pH 6.8 COD and TOC removal rates of 99% and 74%, respectively. The TOC and COD removal rates correspond well with the predicted models. The maximum removal rate for TOC and COD was 99.3% and 76%, respectively at optimum operational conditions of TiO2 dosage (0.5 g/L), ZnO dosage (0.54 g/L), air flow (4.3 L/min), reaction time (170 min) and pH (6.8). The new treatment process achieved higher degradation efficiencies for TOC and COD and reduced the treatment time comparing with other related processes.

Direct ammonia fueled solid oxide fuel cells: A comprehensive review on challenges, opportunities and future outlooks

2020 ◽  
pp. 70-91 ◽  
Author(s):  
Molla Asmare ◽  
Mustafa Ilbas
Keyword(s):  
Electric Power ◽  
Energy Demand ◽  
Renewable Energy Sources ◽  
Clean Energy ◽  
Performance Comparison ◽  
Optimum Operating ◽  
Practical Implementation ◽  
Human Society ◽  
Energy Access ◽  
Green Fuel

Nowadays, the most decisive challenges we are fronting are perfectly clean energy making for equitable and sustainable modern energy access, and battling the emerging alteration of the climate. This is because, carbon-rich fuels are the fundamental supply of utilized energy for strengthening human society, and it will be sustained in the near future. In connection with this, electrochemical technologies are an emerging and domineering tool for efficiently transforming the existing scarce fossil fuels and renewable energy sources into electric power with a trivial environmental impact. Compared with conventional power generation technologies, SOFC that operate at high temperature is emerging as a frontrunner to convert the fuels chemical energy into electric power and permits the deployment of varieties of fuels with negligible ecological destructions. According to this critical review, direct ammonia is obtained as a primary possible choice and price-effective green fuel for T-SOFCs. This is because T-SOFCs have higher volumetric power density, mechanically stable, and high thermal shocking resistance. Also, there is no sealing issue problem which is the chronic issues of the planar one. As a result, the toxicity of ammonia to use as a fuel is minimized if there may be a leakage during operation. It is portable and manageable that can be work everywhere when there is energy demand. Besides, manufacturing, onboard hydrogen deposition, and transportation infrastructure connected snags of hydrogen will be solved using ammonia. Ammonia is a low-priced carbon-neutral source of energy and has more stored volumetric energy compared with hydrogen. Yet, to utilize direct NH3 as a means of hydrogen carrier and an alternative green fuel in T-SOFCs practically determining the optimum operating temperatures, reactant flow rates, electrode porosities, pressure, the position of the anode, thickness and diameters of the tube are still requiring further improvement. Therefore, mathematical modeling ought to be developed to determine these parameters before planning for experimental work. Also, a performance comparison of AS, ES, and CS- T-SOFC powered with direct NH3 will be investigated and best-performed support will be carefully chosen for practical implementation and an experimental study will be conducted for verification based on optimum parameter values obtained from numerical modeling.

scholarly journals Enzymatic Transesterification of Waste Frying Oil from Local Restaurants in East Colombia Using a Combined Lipase System

2020 ◽  
Vol 10 (10) ◽  
pp. 3566
Author(s):  
Mary Angélica Ferreira Vela ◽  
Juan C. Acevedo-Páez ◽  
Nestor Urbina-Suárez ◽  
Yeily Adriana Rangel Basto ◽  
Ángel Darío González-Delgado
Keyword(s):  
Reaction Time ◽  
Methyl Esters ◽  
Enzyme Concentration ◽  
Operating Conditions ◽  
Frying Oil ◽  
Biodiesel Production ◽  
Optimum Operating ◽  
Waste Frying Oil ◽  
Production Chain ◽  
Enzymatic Transesterification

The search for innovation and biotechnological strategies in the biodiesel production chain have become a topic of interest for scientific community owing the importance of renewable energy sources. This work aimed to implement an enzymatic transesterification process to obtain biodiesel from waste frying oil (WFO). The transesterification was performed by varying reaction times (8 h, 12 h and 16 h), enzyme concentrations of lipase XX 25 split (14%, 16% and 18%), pH of reaction media (6, 7 and 8) and reaction temperature (35, 38 and 40 °C) with a fixed alcohol–oil molar ratio of 3:1. The optimum operating conditions were selected to quantify the amount of fatty acid methyl esters (FAMEs) generated. The highest biodiesel production was reached with an enzyme concentration of 14%, reaction time of 8 h, pH of 7 and temperature of 38 °C. It was estimated a FAMEs production of 42.86% for the selected experiment; however, best physicochemical characteristics of biodiesel were achieved with an enzyme concentration of 16% and reaction time of 8 h. Results suggested that enzymatic transesterification process was favorable because the amount of methyl esters obtained was similar to the content of fatty acids in the WFO.

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