scholarly journals Optimization of Operating Conditions for CO2 Methanation Process Using Design of Experiments

Energies ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 8414
Author(s):  
Chae-Eun Yeo ◽  
Minhye Seo ◽  
Dongju Kim ◽  
Cheonwoo Jeong ◽  
Hye-Sun Shin ◽  
...  
Keyword(s):  
Design Method ◽  
Space Velocity ◽  
Operating Conditions ◽  
Catalyst Characterization ◽  
Co2 Conversion ◽  
Optimal Operating ◽  
Co2 Methanation ◽  
Factors Affecting ◽  
Experimental Design Method

In this study, the Taguchi experimental design method using an L16 orthogonal array was attempted in order to investigate the optimal operating conditions for the CO2 methanation process in Ni-based catalysts. The relative influence of the main factors affecting CO2 conversion and CH4 yield was ranked as follows: reactor pressure > space velocity > reaction temperature. The optimal combination of operating conditions was a reactor temperature of 315 °C, a pressure of 19 bar, and a space velocity of 6000 h−1. The effect of the H2/CO2 ratio on CO2 conversion and CH4 yield was further considered under these optimal operating conditions. Moreover, the catalyst was characterized in order to investigate the production of coke through Brunauer–Emmett–Teller analysis, thermogravimetric analysis, and scanning electron microscopy. The amount of coke produced after the reaction for approximately 24 h was ~2 wt.%. Therefore, the desired CH4 yield and long-term operational stability were successfully obtained using the Taguchi design method and catalyst characterization.

scholarly journals Experimental Study on CO2 Methanation over Ni/Al2O3, Ru/Al2O3, and Ru-Ni/Al2O3 Catalysts

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1112 ◽  
Author(s):  
Rei-Yu Chein ◽  
Chih-Chang Wang
Keyword(s):  
Space Velocity ◽  
Molar Ratio ◽  
Ni Catalyst ◽  
Co2 Conversion ◽  
Co2 Methanation ◽  
Temperature Changes ◽  
Good Thermal Stability ◽  
Reverse Water Gas Shift ◽  
Optimum Reaction ◽  
Shift Reaction

CO2 methanation is recognized as one of the best technologies for storing intermittent renewable energy in the form of CH4. In this study, CO2 methanation performance is investigated using Ni/Al2O3, Ru/Al2O3, and Ru-Ni/Al2O3 as the catalysts under conditions of atmospheric pressure, a molar ratio of H2/CO2 = 5, and a space velocity of 5835 h−1. For reaction temperatures ranging from 250 to 550 °C, it was found that the optimum reaction temperature is 400 °C for all catalysts studied. At this temperature, the maximum values of CO2 conversion, H2 efficiency, and CH4 yield and lowest CO yield can be obtained. With temperatures higher than 400 °C, reverse CO2 methanation results in CO2 conversion and CH4 yield decreases with increased temperature, while CO is formed due to reverse water-gas shift reaction. The experimental results showed that CO2 methanation performance at low temperatures can be enhanced greatly using the bimetallic Ru-Ni catalyst compared with the monometallic Ru or Ni catalyst. Under ascending-descending temperature changes between 250 °C and 550 °C, good thermal stability is obtained from Ru-Ni/Al2O3 catalyst. About a 3% decrease in CO2 conversion is found after three continuous cycles (74 h) test.

Innovative approaches on modular apparel design

2017 ◽  
Vol 7 (3) ◽  
pp. 75
Author(s):  
SERDAR EGEMEN NADASBAŞ ◽  
Birsen Cileroglu
Keyword(s):  
Experimental Design ◽  
Mass Customization ◽  
Crucial Role ◽  
Design Method ◽  
New Products ◽  
Apparel Design ◽  
Innovative Methods ◽  
Experimental Design Method ◽  
Financial Growth

Within the globalized environment, the competitiveness,which expresses the talents needed for the sustainability of long term financial growth, has a crucial role affected by innovation and makes significant contributions to the development. One of the innovative methods used by enterprises to remain ahead of the game of competitiveness is mass customization(MC). MC is:“To change,assembly or modify of components of a product or a service according to the desires and needs of the customer”(Piller,2007, p.635). This study aims to determine how to meet the changing desires and demands on clothes with the modularity method of MC.With this respect,common modules which can be applied on different skirts and enables the changes on size&model had been designed,the specialities which models should have were determined and studies on the assembly phase had been performed.This study which was completed with the experimental design method,is important on offering new experiences to the consumers with spare modules applicable to existing clothes and meeting the demand on new products by avoiding the usage of sources on production phase.

scholarly journals CO2 Methanation of Biogas over 20 wt% Ni-Mg-Al Catalyst: on the Effect of N2, CH4, and O2 on CO2 Conversion Rate

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1201
Author(s):  
Danbee Han ◽  
Yunji Kim ◽  
Hyunseung Byun ◽  
Wonjun Cho ◽  
Youngsoon Baek
Keyword(s):  
Reaction Temperature ◽  
Photoelectron Spectroscopy ◽  
Conversion Rate ◽  
Space Velocity ◽  
Molar Ratio ◽  
Co2 Conversion ◽  
X Ray Diffraction ◽  
Co2 Methanation ◽  
X Ray ◽  
Ch4 Production

Biogas contains more than 40% CO2 that can be removed to produce high quality CH4. Recently, CH4 production from CO2 methanation has been reported in several studies. In this study, CO2 methanation of biogas was performed over a 20 wt% Ni-Mg-Al catalyst, and the effects of CO2 conversion rate and CH4 selectivity were investigated as a function of CH4, O2, H2O, and N2 compositions of the biogas. At a gas hourly space velocity (GHSV) of 30,000 h−1, the CO2 conversion rate was ~79.3% with a CH4 selectivity of 95%. In addition, the effects of the reaction temperature (200–450 °C), GHSV (21,000–50,000 h−1), and H2/CO2 molar ratio (3–5) on the CO2 conversion rate and CH4 selectivity over the 20 wt% Ni-Mg-Al catalyst were evaluated. The characteristics of the catalyst were analyzed using Brunauer–Emmett–Teller surface area analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The catalyst was stable for approximately 200 h at a GHSV of 30,000 h−1 and a reaction temperature of 350 °C. CO2 conversion and CH4 selectivity were maintained at 75% and 93%, respectively, and the catalyst was therefore concluded to exhibit stable activity.

Innovative approaches on modular apparel design

2018 ◽  
Vol 7 (3) ◽  
pp. 73-82
Author(s):  
Birsen Cileroglu ◽  
Serdar Egemen Nadasbas
Keyword(s):  
Experimental Design ◽  
Mass Customization ◽  
Crucial Role ◽  
Design Method ◽  
New Products ◽  
Apparel Design ◽  
Innovative Methods ◽  
Experimental Design Method ◽  
Financial Growth

Within the globalized environment, the competitiveness,which expresses the talents needed for the sustainability of long term financial growth, has a crucial role affected by innovation and makes significant contributions to the development. One of the innovative methods used by enterprises to remain ahead of the game of competitiveness is mass customization(MC). MC is to change,assembleor modification of components of a product or a service according to the desires and needs of the customer. This study aims to determine how to meet the changing desires and demands of clothes with the modularity method of MC.With this respect,common modules which can be applied on different skirts and enables the changes on size&model had been designed,the specialities which models should have were determined and studies on the assembly phase had been performed.This study which was completed with the experimental design method,is important on offering new experiences to the consumers with spare modules applicable to existing clothes and meeting the demand on new products by avoiding the usage of sources on production phase.                        Keywords: Mass customization, fashion, innovation, modularity, apparel design

Fatigue Cracking Processes of a Thick-Walled Component of a Chemical Pipeline

2013 ◽  
Vol 586 ◽  
pp. 104-107 ◽  
Author(s):  
Marek Cieśla ◽  
Kazimierz Mutwil
Keyword(s):  
Mechanical Properties ◽  
Degradation Mechanism ◽  
Fatigue Cracking ◽  
Operating Conditions ◽  
Material Structure ◽  
Mechanical Loads ◽  
Factors Affecting ◽  
Term Operation ◽  
Materials Used

At present, there are no generally accepted and widely recognized procedures to determine condition of material of devices subject to complex long-term thermo-mechanical loads. Condition of pipeline material usually changes when subjected to the conditions of long-term operation. Its structure changes and, consequently, so do its mechanical properties, including fatigue characteristics and crack resistance. Therefore, the durability of a component operating under thermal and mechanical loads cannot be discussed separately from its current material properties. This applies in particular to changes that take place in the material micro-structure and to their connection with mechanical properties. This paper covers analyses of stress in the material of a selected pipeline component – pipe tee that is used in chemical plants. Thermo-mechanical interactions determining stress distribution in the component have been taken into account in the calculations. Morphology and location of the cracks indicated that a fatigue-like nature of impacts was the cause of material destruction. Loads of this type occur mainly in conditions of start-up and shut-down. For these reasons, condition of the material in the above-mentioned unstable conditions was subjected to numerical stress analysis. Due to geometric complexity of the pipeline, the distribution of stress in the T-pipe was calculated in two stages: the object was modeled from a global and local perspective. The resulting stress distributions helped to determine factors affecting durability of the tested object. Metallurgy tests were also conducted in order to ascertain factors determining the degradation of material structure and processes of crack formation and development. As a result of research one ascertained that the process of T-pipe cracking under operating conditions was a combined effect of thermo-mechanical and chemical actions determined by the course of intercrystalline corrosion. Synergic interaction of corrosion processes and variable thermal and mechanical loads caused nucleation and propagation of cracks. The crack systems in T-pipe areas subject to the highest stress showed courses characteristic for thermal fatigue of material. The results obtained will identify degradation mechanism of materials used in chemical installations.

scholarly journals CO2 Methanation over Hydrotalcite-Derived Nickel/Ruthenium and Supported Ruthenium Catalysts

Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1008 ◽  
Author(s):  
Joana A. Martins ◽  
A. Catarina Faria ◽  
Miguel A. Soria ◽  
Carlos V. Miguel ◽  
Alírio E. Rodrigues ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Ruthenium Catalysts ◽  
Emission Spectrometry ◽  
Co2 Conversion ◽  
Co2 Methanation ◽  
Inductively Coupled ◽  
Weight Hourly Space Velocity

In this work, in-house synthesized NiMgAl, Ru/NiMgAl, and Ru/SiO2 catalysts and a commercial ruthenium-containing material (Ru/Al2O3com.) were tested for CO2 methanation at 250, 300, and 350 °C (weight hourly space velocity, WHSV, of 2400 mLN,CO2·g−1·h−1). Materials were compared in terms of CO2 conversion and CH4 selectivity. Still, their performances were assessed in a short stability test (24 h) performed at 350 °C. All catalysts were characterized by temperature programmed reduction (TPR), X-ray diffraction (XRD), N2 physisorption at −196 °C, inductively coupled plasma optical emission spectrometry (ICP-OES), and H2/CO chemisorption. The catalysts with the best performance (i.e., the hydrotalcite-derived NiMgAl and Ru/NiMgAl) seem to be quite promising, even when compared with other methanation catalysts reported in the literature. Extended stability experiments (240 h of time-on-stream) were performed only over NiMgAl, which was selected based on catalytic performance and estimated price criteria. This catalyst showed some deactivation under conditions that favor CO formation (high temperature and high WHSV, i.e., 350 °C and 24,000 mLN,CO2·g−1·h−1, respectively), but at 300 °C and low WHSV, excellent activity (ca. 90% of CO2 conversion) and stability, with nearly complete selectivity towards methane, were obtained.

scholarly journals FLUID FLOW BODIES FOR THE PULP AND PAPER INDUSTRY

2020 ◽  
pp. 519-527
Author(s):  
Yuriy Davidovich Alashkevich ◽  
Mikhail Semenovich Lur'e ◽  
Ol'ga Mikhaylovna Lur'e ◽  
Aleksandr Sergeyevich Frolov
Keyword(s):  
Strouhal Number ◽  
Numerical Study ◽  
Design Method ◽  
Signal To Noise Ratio ◽  
Paper Industry ◽  
Vortex Generator ◽  
Pulp And Paper ◽  
Operating Conditions ◽  
Flow Rates ◽  
Experimental Design Method

The question of the use of vortex flowmeters with different versions of the flow body (TO) under operating conditions on the technological lines of pulp and paper production is considered. It is shown that when using different TO in vortex flowmeters, an error occurs in the working range of speeds (flow rates). The observed error arises due to a change in the Strouhal number (Sh) and is associated with the measurement method. In this case, the Strouhal number begins to depend not only on the TO used as a vortex generator, but also on the flow velocity and the concentration of the fibrous suspension. As the main comparative factor for the investigated TOs, the force action on the sensitive element (flexible electrode) located inside the TO was taken. The study was carried out in several stages using numerical modeling and experimental design method. According to the results of a numerical study, the dependence of the Strouhal number (Sh) on the flow rate (V) and the concentration of the suspension (c) is presented. In a comparative analysis of the deviation of the Strouhal number from the average values, it was revealed that MOT No. 1 has a minimal effect on the concentration of the suspension in the working range of flow rates (± 0.5%). This circumstance makes it possible to verify and test flow meters with such maintenance in conventional pouring installations. The analysis of the maintenance with respect to the signal-to-noise ratio shows that the purest signal is generated by the cylindrical maintenance (maintenance No. 3), and maintenance No. 2 and No. 1 have noticeably large noise. The differences are explained by the absence on the surface of a cylindrical TO of extra protrusions, faces, which leads to a smoother flow of a suspension around its surface, as well as to a decrease in internal spurious noise.

scholarly journals Analysis of the factors affecting the dimensional stability of socks using full-factorial experimental design method

2020 ◽  
Vol 15 ◽  
pp. 155892502094821
Author(s):  
Sikander Abbas Basra ◽  
Norina Asfand ◽  
Zeeshan Azam ◽  
Khurram Iftikhar ◽  
Muhammad Awais Irshad
Keyword(s):  
Experimental Design ◽  
Dimensional Stability ◽  
Design Method ◽  
Factorial Experimental Design ◽  
Contributing Factors ◽  
Statistical Tool ◽  
Factors Affecting ◽  
Experimental Design Method ◽  
Full Factorial Experimental Design ◽  
Full Factorial

Socks, which are a necessary item of clothing, need to be comfortable, affordable, and retain their quality throughout their life. Dimensional stability is one of the basic requirements of socks. The purpose of this study is to investigate the contributing factors, that is, elastane percentage, main yarn material, and process type on dimensional stability of socks. Four different percentages of elastane in plaiting yarn (4%, 6%, 8%, and 10%), two main yarns materials (100% cotton and polyester/cotton 52/48), and two process types (wash and bleach) were taken as level of input variables to study the effect on dimensional stability of socks using full-factorial experimental design method. Statistical tool (analysis of variance) was used to check the significant effect of different factors. It was found that with the increase in elastane percentage, shrinkage was decreased. Cotton was found to have more shrinkage percentage as compared to polyester/cotton. In addition, it was observed that washing treatment produced significantly lesser shrinkage than bleaching. These data present a great interest to sock manufacturers who can make better choices to manufacture, dimensionally stable socks.

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