Processes

13 pages, 2224 KiB

Open AccessArticle

Hybridized Particle Swarm—Gravitational Search Algorithm for Process Optimization

by Rajendran Shankar, Narayanan Ganesh, Robert Čep, Rama Chandran Narayanan, Subham Pal and Kanak Kalita

Processes 2022, 10(3), 616; https://doi.org/10.3390/pr10030616 - 21 Mar 2022

Cited by 22 | Viewed by 2901

Abstract

The optimization of industrial processes is a critical task for leveraging profitability and sustainability. To ensure the selection of optimum process parameter levels in any industrial process, numerous metaheuristic algorithms have been proposed so far. However, many algorithms are either computationally too expensive [...] Read more.

The optimization of industrial processes is a critical task for leveraging profitability and sustainability. To ensure the selection of optimum process parameter levels in any industrial process, numerous metaheuristic algorithms have been proposed so far. However, many algorithms are either computationally too expensive or become trapped in the pit of local optima. To counter these challenges, in this paper, a hybrid metaheuristic called PSO-GSA is employed that works by combining the iterative improvement capability of particle swarm optimization (PSO) and gravitational search algorithm (GSA). A binary PSO is also fused with GSA to develop a BPSO-GSA algorithm. Both the hybrid algorithms i.e., PSO-GSA and BPSO-GSA, are compared against traditional algorithms, such as tabu search (TS), genetic algorithm (GA), differential evolution (DE), GSA and PSO algorithms. Moreover, another popular hybrid algorithm DE-GA is also used for comparison. Since earlier works have already studied the performance of these algorithms on mathematical benchmark functions, in this paper, two real-world-applicable independent case studies on biodiesel production are considered. Based on the extensive comparisons, significantly better solutions are observed in the PSO-GSA algorithm as compared to the traditional algorithms. The outcomes of this work will be beneficial to similar studies that rely on polynomial models. Full article

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18 pages, 3192 KiB

Open AccessFeature PaperArticle

High-Performance Extraction Process of Anthocyanins from Jussara (Euterpe edulis) Using Deep Eutectic Solvents

by Nicholas Vannuchi, Anna Rafaela Cavalcate Braga and Veridiana Vera De Rosso

Processes 2022, 10(3), 615; https://doi.org/10.3390/pr10030615 - 21 Mar 2022

Cited by 13 | Viewed by 2582

Abstract

New strategies for obtaining target bioactive compounds and natural pigments with the use of “green solvents” are consistently being developed, and deep eutectic solvents are (DES) a great alternative. This work established the significant variables and models for anthocyanin extraction, using DES and [...] Read more.

New strategies for obtaining target bioactive compounds and natural pigments with the use of “green solvents” are consistently being developed, and deep eutectic solvents are (DES) a great alternative. This work established the significant variables and models for anthocyanin extraction, using DES and experimental design, of Euterpe edulis Mart. (jussara) fruit pulp, an endangered palm tree from the Brazilian Atlantic Forest. From a screening of seven initially tested DES, choline chloride/xylitol-based solvents had the best results with up to 42% increase in the total anthocyanin yield compared to methanolic extraction. Antioxidant assays also revealed a maximum antioxidant capacity of 198.93 mmol Trolox/100 g dry weight basis. The DES extract showed slower degradation to heat at 60° and 90 °C (2.5 times) and indoor constant light source (1.9 times) than methanolic extracts. The optimal extract also revealed slight inhibition of S. enterica and S. aureus growth in the agar plate. Full article

(This article belongs to the Special Issue Innovation in Chemical Plant Design)

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19 pages, 2608 KiB

Open AccessFeature PaperArticle

Modeling and Experimental Studies on Carbon Dioxide Absorption with Sodium Hydroxide Solution in a Rotating Zigzag Bed

by Zhibang Liu, Arash Esmaeili, Hanxiao Zhang, Dan Wang, Yuan Lu and Lei Shao

Processes 2022, 10(3), 614; https://doi.org/10.3390/pr10030614 - 21 Mar 2022

Cited by 3 | Viewed by 2757

Abstract

The enhancement of mass transfer is very important in CO₂ absorption, and a rotating zigzag bed (RZB) is a promising device to intensify the gas–liquid mass transfer efficiency. In this study, the mass transfer characteristics in an RZB in relation to the [...] Read more.

The enhancement of mass transfer is very important in CO₂ absorption, and a rotating zigzag bed (RZB) is a promising device to intensify the gas–liquid mass transfer efficiency. In this study, the mass transfer characteristics in an RZB in relation to the overall gas-phase volumetric mass-transfer coefficient (K_Ga) were investigated with a CO₂–NaOH system. A mathematical model was established to illustrate the mechanism of the gas–liquid mass transfer with irreversible pseudo-first-order reaction in the RZB. The effects of various operating conditions on K_Ga were examined. Experimental results show that a rise in the liquid flow rate, inlet gas flow rate, rotational speed, absorbent temperature, and absorbent concentration was conducive to the mass transfer between gas and liquid in the RZB. It was found that the rotational speed had the largest impact on K_Ga in the RZB. The K_Ga predicted by the model agreed well with that by the experiments, with deviations generally within 10%. Therefore, this model can be employed to depict the mass transfer process between gas and liquid in an RZB and provide guidance for the application of RZBs in CO₂ absorption. Full article

(This article belongs to the Special Issue Industrial Chemistry Reaction: Kinetics, Mass Transfer and Industrial Reactor Design (II))

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13 pages, 6617 KiB

Open AccessArticle

Effects of the Balance Hole Diameter on the Flow Characteristics of the Rear Chamber and the Disk Friction Loss in the Centrifugal Pump

by Wei Dong, Ze Liu, Haichen Zhang, Guang Zhang, Haoqing Jiang and Peixuan Li

Processes 2022, 10(3), 613; https://doi.org/10.3390/pr10030613 - 21 Mar 2022

Cited by 2 | Viewed by 2113

Abstract

This paper studies the flow characteristics and disk friction loss of the rear chamber in a centrifugal pump at a design flow condition with six values of the balance holes at diameters from 0 to 12 mm. The results show that the turbulent [...] Read more.

This paper studies the flow characteristics and disk friction loss of the rear chamber in a centrifugal pump at a design flow condition with six values of the balance holes at diameters from 0 to 12 mm. The results show that the turbulent boundary layer in the rear chamber is greatly affected by the leakage flow. When the balance hole diameter increases, the flow characteristics of the rear chamber is mainly restricted by the mainstream flow field of the volute. However, when the balance hole diameter is larger than the design value, the disk friction loss of the rear chamber remains basically unchanged. On the contrary, when the balance hole diameter is smaller than the design value, the larger the balance hole diameter the smaller the friction loss of the disk in the rear chamber area. The results of this paper provide a reference for reducing axial force and stable operation of a centrifugal pump. Full article

(This article belongs to the Special Issue Design and Optimization Method of Pumps)

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17 pages, 12658 KiB

Open AccessReview

When the Total Hip Replacement Fails: A Review on the Stress-Shielding Effect

by Davide Savio and Andrea Bagno

Processes 2022, 10(3), 612; https://doi.org/10.3390/pr10030612 - 21 Mar 2022

Cited by 38 | Viewed by 9898

Abstract

Total hip arthroplasty is one of the most common and successful orthopedic surgeries. Sometimes, periprosthetic osteolysis occurs associated with the stress-shielding effect: it results in the reduction of bone density, where the femur is not correctly loaded, and in the formation of denser [...] Read more.

Total hip arthroplasty is one of the most common and successful orthopedic surgeries. Sometimes, periprosthetic osteolysis occurs associated with the stress-shielding effect: it results in the reduction of bone density, where the femur is not correctly loaded, and in the formation of denser bone, where stresses are confined. This paper illustrates the stress shielding effect as a cause of the failing replacement of the hip joint. An extensive literature survey has been accomplished to describe the phenomenon and identify solutions. The latter refer to the design criteria and the choice of innovative materials/treatments for prosthetic device production. Experimental studies and numerical simulations have been reviewed. The paper includes an introduction to explain the scope; a section illustrating the causes of the stress shielding effect; a section focusing on recent attempts to redefine prosthetic device design criteria, current strategies to improve the osteointegration process, and a number of innovative biomaterials; functionally graded materials are presented in a dedicated section: they allow customizing prosthesis features with respect to the host bone. Conclusions recommend an integrated approach for the production of new prosthetic devices: the “engineering community” has to support the “medical community” to assure an effective translation of research results into clinical practice. Full article

(This article belongs to the Section Biological Processes and Systems)

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21 pages, 5237 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Catalytic Properties of Free-Base Porphyrin Modified Graphite Electrodes for Electrochemical Water Splitting in Alkaline Medium

by Bogdan-Ovidiu Taranu and Eugenia Fagadar-Cosma

Processes 2022, 10(3), 611; https://doi.org/10.3390/pr10030611 - 21 Mar 2022

Cited by 8 | Viewed by 2139

Abstract

Hydrogen generation via electrochemical water splitting is considered an eco-friendly pathway for obtaining this desired alternative energy source, and it has triggered an intensive search for low cost and efficient catalysts. Within this context, four free-base porphyrins were studied as heterogeneous catalysts for [...] Read more.

Hydrogen generation via electrochemical water splitting is considered an eco-friendly pathway for obtaining this desired alternative energy source, and it has triggered an intensive search for low cost and efficient catalysts. Within this context, four free-base porphyrins were studied as heterogeneous catalysts for the oxygen and hydrogen evolution reactions (OER and HER) in alkaline aqueous solutions. TEM and STEM analyses of samples obtained by drop-casting the porphyrins from different organic solvents on TEM grids revealed a rich variety of aggregates due to the self-assembling property of the porphyrin molecules. Modified electrodes were manufactured by applying the four tetrapyrrolic macrocycles from various solvents on the surface of graphite supports, in one or more layers. Experiments performed in 0.1 M and 1 M KOH electrolyte solutions allowed the identification of the most electrocatalytically active electrodes for the OER and HER, respectively. In the first case, the electrode was manufactured by applying three layers of 5-(4-pyridyl)-10,15,20-tris(4-phenoxyphenyl)porphyrin on the graphite substrate from N,N-dimethylformamide solution was identified as overall catalytically superior. In the second case, the electrode obtained by applying one layer of 5,10,15,20-tetrakis(4-allyloxyphenyl)-porphyrin from benzonitrile solution displayed an HER overpotential value of 500 mV at i = −10 mA/cm² and a Tafel slope of 190 mV/dec. Full article

(This article belongs to the Special Issue From Small Molecules to High-Value Chemicals: Theory and Practice)

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14 pages, 6546 KiB

Open AccessFeature PaperArticle

Quantitative Measurement of Solids Holdup for Group A and B Particles Using Images and Its Application in Fluidized Bed Reactors

by Chengxiu Wang, Zhihui Li, Jianjin Wei, Xingying Lan, Mao Ye and Jinsen Gao

Processes 2022, 10(3), 610; https://doi.org/10.3390/pr10030610 - 21 Mar 2022

Cited by 5 | Viewed by 1889

Abstract

Solids holdup as one of the main parameters in characterizing the performance of fluidized bed reactors is widely concerned. With its development and improvement, visualization technology has been applied in fluidization because of its little disturbance to the flow. In this study, four [...] Read more.

Solids holdup as one of the main parameters in characterizing the performance of fluidized bed reactors is widely concerned. With its development and improvement, visualization technology has been applied in fluidization because of its little disturbance to the flow. In this study, four types of particles with different properties are tested in a narrow rectangular fluidized bed equipped with a high-speed video camera. Calibration curves of these different types of particles are achieved by correlating the grayscale of the digital images with the corresponding solids holdup. These calibration curves are further applied to obtain the average solids holdup across the sectional area and local solids holdup from the center towards the wall in both a gas-solids turbulent fluidized bed and a circulating fluidized bed to verify the results. The calibration method works well for solids holdup of different types of particles in both dense and dilute fluidization systems. This method is important to characterize the fluidization quality and reactor performance with a wide operating condition. Full article

(This article belongs to the Section Particle Processes)

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20 pages, 3325 KiB

Open AccessArticle

A Multicriteria Decision Trading System Based on Prospect Theory: A Risk Return Analysis of the TODIM Method

by Bruna Puppo, Michel Leles, Leonardo Mozelli and Elton Sbruzzi

Processes 2022, 10(3), 609; https://doi.org/10.3390/pr10030609 - 21 Mar 2022

Cited by 2 | Viewed by 2293

Abstract

This paper proposes a trading system (TS) based on a multicriteria decision aid (MCDA) process known as TODIM, (Multicriteria Interactive Decision Making) a Portuguese acronym for interactive and multicriteria decision-making. MCDA has been employed to solve financial questions because of its ability to [...] Read more.

This paper proposes a trading system (TS) based on a multicriteria decision aid (MCDA) process known as TODIM, (Multicriteria Interactive Decision Making) a Portuguese acronym for interactive and multicriteria decision-making. MCDA has been employed to solve financial questions because of its ability to deal with a complex environment populated with different sorts of criteria and alternatives, such as financial markets. The aim is to propose a general and adaptive tool for supporting the trading strategies of investors and market practitioners in such an environment. The reason for selecting TODIM among the different MCDA methods is that it is based on prospect theory, which assumes that the risk profile of the investor varies according to different situations, considering the risk of loss or gain. A list of simulations using some of the most prominent Brazilian stocks is performed, and the results are compared with the Buy-and-Hold benchmark and a TS based on an ensemble method for selecting trading rules. The results show that, compared to Buy-and-Hold, a TODIM-based TS provides the same level of return with a lower level of risk exposure. The consequence is superior risk adjustment parameters. As a result, we have a model with similar results in profit, but with superior results in relation to risk-based performance, which makes the method advantageous in relation to similar ones. Full article

(This article belongs to the Special Issue Advanced Multiple Criteria Decision-Making Methods for Novel Applications)

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2 pages, 150 KiB

Open AccessEditorial

Special Issue on “Synthesis and Application of Nano- and Microdispersed Systems”

by Denis Kuznetsov and Gopalu Karunakaran

Processes 2022, 10(3), 608; https://doi.org/10.3390/pr10030608 - 21 Mar 2022

Viewed by 1258

Abstract

With numerous advancements, nano- and microdispersed systems are rapidly increasing worldwide [...] Full article

(This article belongs to the Special Issue Synthesis and Application of Nano- and Microdispersed Systems)

23 pages, 6611 KiB

Open AccessArticle

Investigations of Middle-Caliber Anti-Aircraft Cannon Interior Ballistics including Heat Transfer Problem in Estimation of Critical Burst Length

by Bartosz Fikus, Alicja Dorochowicz, Zbigniew Surma, Jacek Kijewski, Zbigniew Leciejewski, Jakub Michalski and Radosław Trębiński

Processes 2022, 10(3), 607; https://doi.org/10.3390/pr10030607 - 20 Mar 2022

Cited by 7 | Viewed by 2297

Abstract

Numerical and experimental investigations of armament systems are an important part of modern design processes. The presented paper reports problems that were encountered on the theoretical analysis of the performance of 35 mm anti-aircraft cannon and the way in which they were solved. [...] Read more.

Numerical and experimental investigations of armament systems are an important part of modern design processes. The presented paper reports problems that were encountered on the theoretical analysis of the performance of 35 mm anti-aircraft cannon and the way in which they were solved. The first problem concerns the application of results of closed vessel tests of used propellant in interior ballistics simulations. The use of a nonstandard form of the gas generation rate equation solved this problem. The second problem concerned the assessment of projectile–barrel interaction. The barrel resistance was estimated making use of finite element analysis. The third problem arose from the need to determine the heat transfer from propellant gases to the barrel. The employed formula for the heat exchange coefficient and 2D modelling of the heat conduction in the barrel provided the solution. Selected elements of the theoretical model were validated by shooting range experiments and data provided by the ammunition producer. Using the considered approach, crucial ballistic parameters (maximum propellant gas pressure and muzzle velocity) were estimated with an error of less than 6.0%, without application of additional fitting coefficients. The numerical estimation of the barrel external surface temperature provided a relative discrepancy with the experimental data lower than 6% and enabled the estimation of the critical burst length, equal to 14 shots. Full article

(This article belongs to the Special Issue Advances in CFD Analysis of Convective Heat Transfer)

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16 pages, 5126 KiB

Open AccessArticle

Research and Application of Power Grid Maintenance Scheduling Strategy under the Interactive Mode of New Energy and Electrolytic Aluminum Load

by Bin Zhang, Hongchun Shu, Dajun Si, Wenyun Li, Jinding He and Wenlin Yan

Processes 2022, 10(3), 606; https://doi.org/10.3390/pr10030606 - 20 Mar 2022

Cited by 3 | Viewed by 1870

Abstract

Formulating a reasonable and feasible unit maintenance scheme is a promising way to eliminate potential risks and improve the reliability of power systems. However, the uncertainty and volatility of new energy outputs, such as wind power, increase the difficulty of scheme formulation. To [...] Read more.

Formulating a reasonable and feasible unit maintenance scheme is a promising way to eliminate potential risks and improve the reliability of power systems. However, the uncertainty and volatility of new energy outputs, such as wind power, increase the difficulty of scheme formulation. To overcome the complexity of uncertainty, a robust unit maintenance scheme considering the uncertainty of new energy output and electrolytic aluminum load is established in this paper. Considering the significant time-series characteristics of new energy, this paper first introduces the definition and mathematical model of information granulation (IG), through which the initial new energy output data can be transformed into fuzzy particles used for prediction and analysis. Moreover, a support-vector machine (SVM) regression prediction model is adopted, and a corresponding progressive search algorithm is designed to determine SVM parameters efficiently. Then, a robust unit maintenance model is established considering the upper and lower predicted error. In addition, electrolytic aluminum loads are allowed to participate in power system dispatch. Finally, the modified reliability test system–Grid Modernization Lab Consortium (RTS–GMLC test system) and an actual power grid in Southwest China are used to verify the accuracy and feasibility of the proposed method. Full article

(This article belongs to the Topic Electricity Demand-Side Management)

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16 pages, 8715 KiB

Open AccessArticle

Effect of Static and Dynamic Stretching on Corneal Fibroblast Cell

by Zhi-Xuan Dai, Po-Jen Shih, Jia-Yush Yen and I-Jong Wang

Processes 2022, 10(3), 605; https://doi.org/10.3390/pr10030605 - 20 Mar 2022

Cited by 3 | Viewed by 2329

Abstract

A strain gradient was created by punching a hole in the center of a stretched elastic polydimethylsiloxane membrane to determine the effect of different strains on cultured human keratocytes (HK). In this study, two stretching methods were used: continuous stretching and cyclic stretching. [...] Read more.

A strain gradient was created by punching a hole in the center of a stretched elastic polydimethylsiloxane membrane to determine the effect of different strains on cultured human keratocytes (HK). In this study, two stretching methods were used: continuous stretching and cyclic stretching. Continuous stretching is relatively static, while acyclic stretching is relatively dynamic. These methods, respectively, represented the effects of high intraocular pressure and rubbing of the eyes on corneal cells. Image processing codes were developed to observe the effects of stress concentration, shear stress, continuous stretching, and cyclic stretching on HKs. The results demonstrate that stretching and shear stress are not conducive to the proliferation of corneal cells and instead cause cell death. A 10% strain had greater inhibitory effects than a 3% strain on cell proliferation. Cell survival rates for continuous stretching (static) were higher than those for cyclic stretching (dynamic). The stretching experiment revealed that cyclic stretching has a greater inhibitory effect on the growth and proliferation of corneal cells than continuous stretching. Accordingly, it shows that cyclic loading is more harmful than high intraocular pressure (static loading) to corneal cells. Full article

(This article belongs to the Special Issue Advances in Cell Death Pathways)

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12 pages, 1684 KiB

Open AccessArticle

Improvement of the Gut Microbiota In Vivo by a Short-Chain Fatty Acids-Producing Strain Lactococcus garvieae CF11

by Shuting Fang, Tian Qin, Ting Yu and Guoxia Zhang

Processes 2022, 10(3), 604; https://doi.org/10.3390/pr10030604 - 20 Mar 2022

Cited by 8 | Viewed by 2909

Abstract

Gut microbiota has strong connections with health. Regulating and enhancing gut microbiota and increasing the population of beneficial microorganisms constitutes a new approach to increasing the efficiency of health status. Although it has been shown that Lactococcus can adjust gut microbiota and be [...] Read more.

Gut microbiota has strong connections with health. Regulating and enhancing gut microbiota and increasing the population of beneficial microorganisms constitutes a new approach to increasing the efficiency of health status. Although it has been shown that Lactococcus can adjust gut microbiota and be beneficial for the host, little is known about whether strains of Lactococcus petauri can improve the gut microbiota. This study focused on the influence of Lactococcus petauri CF11 on the gut microbiome composition and the levels of short-chain fatty acids (SCFAs) in vivo in healthy Sprague Dawley rats. The present results showed that strain CF11 was able to induce a higher amount of fecal acetic acid and propionic acid and enhance species richness. Moreover, strain CF11 improved the gut microbiota community structure. In the experimental group, the genera Oscillospira, Coprococcus, and Ruminococcus, which are reported to be able to produce SCFAs, are significantly increased when compared with the control group (p < 0.05). Finally, the functions of genes revealed that 180 pathways were upregulated or downregulated in comparison with the control group. Among them, the top-five clearly enriched pathways regarding metabolism included porphyrin and chlorophyll metabolism; C5-Branched dibasic acid metabolism; valine, leucine, and isoleucine biosynthesis; phenylalanine, tyrosine, and tryptophan biosynthesis; and ascorbate and aldarate metabolism. Our data suggest that the SCFAs-producing strain CF11 is a potential probiotic. Full article

(This article belongs to the Special Issue Nitrogen Cycling Processes in Coastal Ecosystems)

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24 pages, 4851 KiB

Open AccessFeature PaperArticle

Modeling the Biosorption Process of Heavy Metal Ions on Soybean-Based Low-Cost Biosorbents Using Artificial Neural Networks

by Daniela Ionela Fertu, Elena Niculina Dragoi, Laura Bulgariu, Silvia Curteanu and Maria Gavrilescu

Processes 2022, 10(3), 603; https://doi.org/10.3390/pr10030603 - 20 Mar 2022

Cited by 7 | Viewed by 2141

Abstract

Pollution of the environment with heavy metals requires finding solutions to eliminate them from aqueous flows. The current trends aim at exploiting the advantages of the adsorption operation, by using some low-cost sorbents from agricultural waste biomass, and with good retention capacity of [...] Read more.

Pollution of the environment with heavy metals requires finding solutions to eliminate them from aqueous flows. The current trends aim at exploiting the advantages of the adsorption operation, by using some low-cost sorbents from agricultural waste biomass, and with good retention capacity of some heavy metal ions. In this context, it is important to provide tools that allow the modeling and optimization of the process, in order to transpose the process to a higher operating scale of the biosorption process. This paper capitalizes on the results of previous research on the biosorption of heavy metal ions, namely Pb(II), Cd(II), and Zn(II) on soybean biomass and soybean waste biomass resulting from biofuels extraction process. The data were processed by applying a methodology based on Artificial Neural Networks (ANNs) and evolutionary algorithms (EAs) capable of evolving ANN parameters. EAs are represented in this paper by the Differential Evolution (DE) algorithm, and a simultaneous training and determination of the topology is performed. The resulting hybrid algorithm, hSADE-NN was applied to obtain optimal models for the biosorption process. The expected response of the system addresses biosorption capacity of the biosorbent (q, mg/g), the biosorption efficiency (E, %), as functions of input parameters: pH, biosorbent dose (DS, mg/g), the initial concentration of metal in the solution (c₀, mg/L), contact time (t_c, h), and temperature (T, °C). Models were developed for the two output variables, for each metal ion, finding a high degree of accuracy. Furthermore, the combinations of input parameters were found which can lead to an optimal output in terms of biosorption capacity and biosorption efficiency. Full article

(This article belongs to the Special Issue Innovative Materials and Processes for Removal of Biopersistent Pollutants)

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20 pages, 5954 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Application of Nanodiamonds in Modelled Bioremediation of Phenol Pollution in River Sediments

by Ivaylo Yotinov, Mihaela Belouhova, Anna Foteva, Nora Dinova, Yovana Todorova, Irina Schneider, Elmira Daskalova and Yana Topalova

Processes 2022, 10(3), 602; https://doi.org/10.3390/pr10030602 - 19 Mar 2022

Cited by 2 | Viewed by 2197

Abstract

The pollution of aquatic ecosystems is a big problem that has its impact on river sediments. In recent decades, an effective solution to this problem has been the application of bioremediation technologies. Nanoremediation is an innovative part of these technologies. We still know [...] Read more.

The pollution of aquatic ecosystems is a big problem that has its impact on river sediments. In recent decades, an effective solution to this problem has been the application of bioremediation technologies. Nanoremediation is an innovative part of these technologies. We still know little about the efficiency of nanoparticles, especially nanodiamonds, in modelled conditions. The aim of the present study is to investigate the effect of nanodiamonds on the key parameters of modelled bioremediation of river sediments that are polluted with phenol, as well their effect on the structures and functions of microbial communities. An important indicative mechanism that was used is the application of fluorescent in situ hybridization for sediment microbial communities. The results of this study revealed the positive role of nanodiamonds that is associated with their intoxication with high concentrations of phenol. Readaptation was also found, in which the xenobiotic biodegradation potential evolved by increasing the relative proportions of non-culturable bacteria, namely Acinetobacter (at the 144th hour) and Pseudomonas (at the 214th hour). The results can help to find an effective solution to the question of how information from such precise molecular methods and the application of nanodiamonds can be translated into the accessible language of management and bioremediation technologies. Full article

(This article belongs to the Special Issue Sustainable Shift to Circular Solutions for Water and Waste Management)

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13 pages, 2491 KiB

Open AccessArticle

Developing a New Algorithm to Design Thermo-Vapor Compressors Using Dimensionless Parameters: A CFD Approach

by Mohammad Malakootikhah, Mehrab Valizadehderakhshan, Abolghasem Shahbazi and Arjomand Mehrabani-Zeinabad

Processes 2022, 10(3), 601; https://doi.org/10.3390/pr10030601 - 19 Mar 2022

Cited by 2 | Viewed by 1946

Abstract

This paper aims to propose a new algorithm for designing thermal vapor compressors (TVCs) using given operation parameters. First, an axisymmetric model was used to simulate a TVC, and the results were compared with those from published experimental results. A simulation set was [...] Read more.

This paper aims to propose a new algorithm for designing thermal vapor compressors (TVCs) using given operation parameters. First, an axisymmetric model was used to simulate a TVC, and the results were compared with those from published experimental results. A simulation set was designed to analyze the TVC dimensions, and then statistically-significant parameters (p-value < 0.05) were chosen for the subsequent studies. Thereafter, three parametric lengths were defined and a model presenting entrainment ratio (ER) was developed using a set of simulation results. The obtained characteristic equation allows us to scale (up or down) the TVC to different capacities, calculate the real-time sizes or predict the performance. It was found that the critical “TVC/primary nozzle” throat diameter ratio is constant in every scale-up study, depending on operation conditions. By establishing a characteristic graph, the approach was expanded for a broader algorithm. The comparative results revealed that this approach is able to predict the ER for every scaling study with an error of less than 2.8%. This approach can be used to devise TVCs ejectors using any given ER and capacity within the ranges of possible usage. Full article

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14 pages, 3099 KiB

Open AccessArticle

Eulerian–Lagrangian–Eulerian Simulations of Two-Phase Minimum Quantity Lubrication Flow in Internal Drill Bit Channels

by Manuel Falcone, Lizoel Buss and Udo Fritsching

Processes 2022, 10(3), 600; https://doi.org/10.3390/pr10030600 - 19 Mar 2022

Cited by 4 | Viewed by 1685

Abstract

The goal of reducing oil consumption for lubrication of machining processes can be achieved by means of minimum quantity lubrication (MQL). In minimum quantity lubrication, the cutting fluid is a mixture of air and oil where only a small amount of the latter [...] Read more.

The goal of reducing oil consumption for lubrication of machining processes can be achieved by means of minimum quantity lubrication (MQL). In minimum quantity lubrication, the cutting fluid is a mixture of air and oil where only a small amount of the latter is added to the mixture. However, this reduced oil consumption must not be detrimental to the effectiveness of the machining process. In order to analyze the performance of minimum quantity lubrication, the two-phase fluid dynamics of the MQL dispersion fluid has to be investigated. In the present work, this two-phase flow for internal lubrication of a drilling process was studied by means of numerical modeling and simulation based on an Eulerian–Lagrangian–Eulerian (ELE) model. The Eulerian–Lagrangian–Eulerian model can properly describe the transition between the aerosol and wall liquid film two-phase flow. Attention was focused on the flow in the internal channels of a twist drill. A parametric study was carried out in order to disclose the effects of three different relevant parameters, namely the oil droplet diameter and the mass flow rate at the channel inlet and the drill bit rotational speed, on the MQL cutting fluid flow quality inside the drill bit channel and at the channel outlet. Full article

(This article belongs to the Special Issue Multifluid Computational Fluid Dynamic Simulation)

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12 pages, 3701 KiB

Open AccessArticle

Pilot-Scale Experimental Study of a New High-Loading Absorbent for Capturing CO₂ from Flue Gas

by Yi Ye, Xinglei Zhao, Jian Chen and Mengxiang Fang

Processes 2022, 10(3), 599; https://doi.org/10.3390/pr10030599 - 19 Mar 2022

Cited by 5 | Viewed by 2074

Abstract

Chemical absorbents with low-energy requirements have become the primary focus of the research on CO₂ capture from flue gas in power plants. To verify the absorption performance of the NICE absorbent developed by the National Institute of Clean-and-Low-Carbon Energy in China, a [...] Read more.

Chemical absorbents with low-energy requirements have become the primary focus of the research on CO₂ capture from flue gas in power plants. To verify the absorption performance of the NICE absorbent developed by the National Institute of Clean-and-Low-Carbon Energy in China, a performance optimization test was conducted in Zhejiang University’s pilot-scale platform, and the effects of the liquid–gas ratio, regeneration pressure, rich liquid fractional flow, and interstage cooling on the absorption performance and regeneration energy consumption were investigated. The results showed that in the CO₂ pilot test, the optimized minimum regeneration energy consumption was 2.85 GJ/t CO₂, and the corresponding process parameters were as follows: a liquid–gas ratio of 1.82 L/m³, regeneration pressure of 191 kPa, an interstage cooling temperature of 40 °C, and a rich liquid fractional flow ratio of 0.18. This study preliminarily verified the low-energy consumption performance of the NICE absorbent and showed its good potential for industrial applications. Additionally, the NICE absorbent showed promise for capital and operating cost savings because of its low liquid–gas ratio. Full article

(This article belongs to the Topic Carbon Capture, Storage and Utilisation Technologies (CCS/CCU))

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28 pages, 9781 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Origin of Steam Contaminants and Degradation of Solid-Oxide Electrolysis Stacks

by Dominik Schäfer, Larissa Queda, Volker Nischwitz, Qingping Fang and Ludger Blum

Processes 2022, 10(3), 598; https://doi.org/10.3390/pr10030598 - 19 Mar 2022

Cited by 4 | Viewed by 2395

Abstract

Two once-through steam generators and a combination of a steam generator and a gas preheater for supplying feed gases to solid-oxide electrolysis stacks were evaluated for their carryover characteristics of contaminants from the feed-water into the steam phase. The concentrations of various trace [...] Read more.

Two once-through steam generators and a combination of a steam generator and a gas preheater for supplying feed gases to solid-oxide electrolysis stacks were evaluated for their carryover characteristics of contaminants from the feed-water into the steam phase. The concentrations of various trace impurities in the steam were determined by sampling the steam condensates and screening them with inductively coupled plasma–mass spectrometry for 19 elements and liquid ion chromatography and continuous flow analysis for chloride and ammonium. Steam-soluble species such as boric acid undergo complete volatilization and transfer into the steam phase. During unstable evaporation in the steam generators an extensive physical carryover of alloying metal species was observed. At realistic operation conditions for steam electrolysis, the gas preheater caused a considerable release of silicon into the steam phase. Two stack experiments were performed with common preheater temperatures and showed largely increased cell voltage degradation at higher operation temperatures. The post-test chemical analysis of cell samples revealed significant concentrations of silicon in the samples that are regarded as primary cause for increased degradation. These findings could partially explain the wide spread of degradation rates reported for solid-oxide steam electrolysis experiments. Full article

(This article belongs to the Section Energy Systems)

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44 pages, 7089 KiB

Open AccessEditor’s ChoiceReview

Experimental Characterization Techniques for Solid-Liquid Slurry Flows in Pipelines: A Review

by Rui C. Silva

Processes 2022, 10(3), 597; https://doi.org/10.3390/pr10030597 - 18 Mar 2022

Cited by 9 | Viewed by 5744

Abstract

In industrial environments, having instrumentation able to attain fast, accurate, and autonomous measurements is pivotal to understanding the dynamics of liquid and particles during transport. Ideally, these instruments, consisting of either probes or sensors, should be robust, fast, and unintrusive, i.e., not cause [...] Read more.

In industrial environments, having instrumentation able to attain fast, accurate, and autonomous measurements is pivotal to understanding the dynamics of liquid and particles during transport. Ideally, these instruments, consisting of either probes or sensors, should be robust, fast, and unintrusive, i.e., not cause interference on the very flows being monitored, and require minimal maintenance. Beyond monitoring, the process knowledge gained through real time inspection allows teams to make informed technical decisions based on particle behavior, i.e., settling of particles causing pipe wear and clustering or blockages that can damage the unit or cause shutdowns, both of which with economical drawbacks. The purpose of this review is to examine experimental measurement techniques used to characterize physical properties and operational parameters of solid-liquid slurry flows, focusing on non-ionizing radiation methods. With this text the intent is not to provide an exhaustive examination of each individual technique but rather an overview on the most pertinent types of instrumentation, which will be presented, in addition to application examples from the literature, while directing the reader for pertinent seminal and review papers for a more in-depth analysis. Full article

(This article belongs to the Section Process Control and Monitoring)

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18 pages, 3728 KiB

Open AccessReview

Systematic Literature Review on Remanufacturing Trade Based on Bibliometric Analysis

by Xumei Zhang, Ruyuan Liu, Wei Yan, Yan Wang and Nachiappan Subramanian

Processes 2022, 10(3), 596; https://doi.org/10.3390/pr10030596 - 18 Mar 2022

Cited by 2 | Viewed by 2062

Abstract

With the extensive development of remanufacturing, remanufacturing trade, as an essential part of it, has also attracted much attention from researchers. Quite a large number of studies related to remanufacturing trade, such as pricing, sales, competition, channel expansion and service strategy, have been [...] Read more.

With the extensive development of remanufacturing, remanufacturing trade, as an essential part of it, has also attracted much attention from researchers. Quite a large number of studies related to remanufacturing trade, such as pricing, sales, competition, channel expansion and service strategy, have been published in various journals. This paper aims to focus on the research status on remanufacturing trade through bibliometric analysis that can provide the primary research trends and the future research hotspots by analyzing the progress, parties and themes of the research. In this paper, the review and analysis are conducted on over 121 articles from 2000 until July 2021 with the help of VOS viewer (Leiden University, Leiden, The Netherlands) and Citespace (Drexel University, Philadelphia, PA, USA). The results of the analysis of research progress and research parties suggest that: (a) more and more researchers have started to pay attention to consumers during modeling; (b) sustainable/green aspects are frequently taken into account as a factor, but the sustainable/green standards for remanufacturing trade need to be further developed; (c) studies on remanufacturing trade are more abundant in heavy industry countries. Additionally, the hotspots for future research are identified via the theme analysis, including: (1) with the issuing of various government policies, the impact of these policies on decisions related to remanufacturing trade has been studied gradually and is expected to become a hot topic in the future; (2) a large number of papers conduct research on the basis of the supply chain of remanufactured products; (3) research on the online distribution channel has already been carried out and is constantly deepening; (4) the digital technology is increasingly introduced to remanufacturing trade in recent years. Full article

(This article belongs to the Section Manufacturing Processes and Systems)

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21 pages, 3982 KiB

Open AccessFeature PaperArticle

Thermal Storage Performance of Underground Cave Dwellings under Kang Intermittent Heating: A Case Study of Northern China

by Jiayin Zhu, Yingfang Liu, Ruixin Li, Bin Chen, Yu Chen and Jifu Lu

Processes 2022, 10(3), 595; https://doi.org/10.3390/pr10030595 - 18 Mar 2022

Cited by 2 | Viewed by 1750

Abstract

The intermittent heating mode of Kang plays an important role in the heat storage and release in cave dwellings. However, research on the effect of Kang heating on the thermal process of traditional buildings is rare. Therefore, based on long-term monitoring of cave [...] Read more.

The intermittent heating mode of Kang plays an important role in the heat storage and release in cave dwellings. However, research on the effect of Kang heating on the thermal process of traditional buildings is rare. Therefore, based on long-term monitoring of cave dwellings, regular conclusions about the influence of Kang heating on the thermal environment were obtained. Furthermore, an unsteady heat transfer model of the envelope was proposed for the first time. Then, based on this model, the thermal storage performance of cave dwellings during the period of Kang intermittent heating was explored. The results showed that, due to Kang heating, the indoor air temperature of cave dwellings could be increased by an average of 3.1 °C. Furthermore, the inner walls had a large thermal mass and the maximum heat storage in a single day was 487.75 kJ/m², while the maximum heat release was 419.02 kJ/m². The heat release at night could reach 87%. In this paper, the law of thermal storage and release characteristics of earthen building envelopes under intermittent heating was firstly obtained. Results can enrich the thermal process theory of earthen buildings and provide a theoretical basis and technical support for building thermal environmental construction. Full article

(This article belongs to the Special Issue Recent Advances in Environmental Pollution Control and Coal Combustion)

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10 pages, 1574 KiB

Open AccessFeature PaperArticle

Enzymatic Synthesis of the Fructosyl Derivative of Sorbitol

by Milena Bors, Robert Klewicki, Michał Sójka and Elżbieta Klewicka

Processes 2022, 10(3), 594; https://doi.org/10.3390/pr10030594 - 18 Mar 2022

Viewed by 1591

Abstract

The aim of the study was to determine the effect of selected reaction parameters—temperature (37–57 °C), pH (5.8–7.9), substrates ratio (sucrose/sorbitol 0.5/1.5 to 1.5:0.5 (m/m)), and the presence of NaCl—on the course of fructosyl-sorbitol synthesis with an enzyme preparation (11 760 U/100 g [...] Read more.

The aim of the study was to determine the effect of selected reaction parameters—temperature (37–57 °C), pH (5.8–7.9), substrates ratio (sucrose/sorbitol 0.5/1.5 to 1.5:0.5 (m/m)), and the presence of NaCl—on the course of fructosyl-sorbitol synthesis with an enzyme preparation (11 760 U/100 g of sucrose) containing fructosyltransferase and β-d-fructofuranosidase from Aspergillus niger. A mixture of at least three fructosyl sorbitol derivatives was obtained: two mono-fructosyl and one di-fructosyl. The highest content of all sorbitol derivatives combined was 2.7 g/100 mL for pH 6.8–6.9, and the sucrose/sorbitol ratio was 1:1. Increasing the reaction temperature from 37 to 57 °C reduced the time required to reach the maximum product content from 5 to 2 h, while the concentration did not increase. The addition of NaCl (0.63 M) extended the reaction time from 2 to 5 h and slightly lowered the maximum concentration of sorbitol derivatives (from 2.74 to 2.6 g/100 mL). Full article

(This article belongs to the Special Issue Method Optimization of Various Food Processing Technologies)

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13 pages, 4286 KiB

Open AccessArticle

Influence Mechanism of Gas–Containing Characteristics of Annulus Submerged Jets on Sealing Degree of Mixing Zone

by Chao Wang, Chuanzhen Wang, Jun Xie and Md Shakhaoath Khan

Processes 2022, 10(3), 593; https://doi.org/10.3390/pr10030593 - 18 Mar 2022

Cited by 2 | Viewed by 1731

Abstract

The introduction of air into a submerged annular jet will result in dispersion of the jet, which will affect the degree of enclosure of the gas–water mixing zone in the annular jet nozzle, and then have a significant impact on air suction and [...] Read more.

The introduction of air into a submerged annular jet will result in dispersion of the jet, which will affect the degree of enclosure of the gas–water mixing zone in the annular jet nozzle, and then have a significant impact on air suction and the formation of the foam system in the floatation process. A numerical simulation method is used to analyze the characteristics of the distribution of the axial flow velocity of annular jets, gas–phase volume, and turbulence intensity in the gas–water mixing zone in the nozzle with different air–liquid ratios, and thereby reveal the mechanism whereby gas–containing in annular jets affects the degree of enclosure of the gas–water mixing zone. The results show that as the air–liquid ratio increases, the degree of air–liquid mixing will increase and the radial flow velocity will decrease gradually, resulting in the effective enclosure of the gas–water mixing zone. Meanwhile, the dissipation of jet energy, the range of turbulent flow and the vorticity intensity will increase, but the turbulence intensity will decrease. When the gas–water mixing zone is fully enclosed, as gas–containing continues to increase, the degree of dispersion of the annular jet will further increase. Consequently, the area of the gas–water mixing zone with bounced–back water will become larger, resulting in a higher axial flow velocity, larger local turbulence intensity and larger vorticity intensity. This will lead to the dissipation of jet energy, which is not favorable for air suction. Full article

(This article belongs to the Special Issue Computational Modeling of Multiphase Flow (II))

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9 pages, 267 KiB

Open AccessArticle

The Anti-Hypertensive and Hypoglycemic Potential of Bioactive Compounds Derived from Pulasan Rind

by Seok Shin Tan, Seok Tyug Tan and Chin Xuan Tan

Processes 2022, 10(3), 592; https://doi.org/10.3390/pr10030592 - 18 Mar 2022

Cited by 3 | Viewed by 1864

Abstract

Pulasan (Nephelium mutabile Blume) is an underutilized fruit native to tropical countries, including Malaysia, Thailand, and Indonesia. To date, the medicinal potential of pulasan remains unexplored, although this fruit shares the same genus with the well-known rambutan (Nephelium lappaceum). [...] Read more.

Pulasan (Nephelium mutabile Blume) is an underutilized fruit native to tropical countries, including Malaysia, Thailand, and Indonesia. To date, the medicinal potential of pulasan remains unexplored, although this fruit shares the same genus with the well-known rambutan (Nephelium lappaceum). Therefore, the current study aims to examine the antioxidant properties of different parts of pulasan (flesh, rind, and kernel) and investigate the bioactive profile, anti-hypertensive and hypoglycemic properties of pulasan rind. Pulasan were extracted using different solvents, including distilled water, methanol, and ethanol. The antioxidant capacity was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP), and the antioxidant component was identified by total flavonoid content (TFC) and total phenolic content (TPC). The bioactive profile of pulasan rind was characterized by high-performance liquid chromatography (HPLC). The anti-hypertensive and hypoglycemic properties of pulasan rind were determined with angiotensin-converting enzyme (ACE) assay and alpha-amylase inhibition assay, respectively. Emerging findings revealed that pulasan rind exhibited the highest antioxidant capacity (DPPH, TEAC, and FRAP) in all extraction solvents and antioxidant components (TPC and TFC) in ethanolic extract. The ethanolic extracts of pulasan rind also had higher ACE and alpha-amylase inhibition activities than the distilled water extracts. Geraniin, chlorogenic acid, catechin, corilagin, syringic acid, and naringenin of pulasan rind may function as anti-hypertensive agents. Full article

(This article belongs to the Special Issue Bioactive Compounds from Food Waste and By-Products)

15 pages, 2763 KiB

Open AccessFeature PaperArticle

Construction of Recombinant Magnetospirillum Strains for Nitrate Removal from Wastewater Based on Magnetic Adsorption

by Haolan Zheng, Bo Pang, Shuli Li, Shijiao Ma, Junjie Xu, Ying Wen and Jiesheng Tian

Processes 2022, 10(3), 591; https://doi.org/10.3390/pr10030591 - 18 Mar 2022

Cited by 4 | Viewed by 1651

Abstract

Nitrate ion (NO₃⁻) in wastewater is a major cause of pollution in aquatic environments worldwide. Magnetospirillum gryphiswaldense (MSR-1) has a complete dissimilatory denitrification pathway, converts NO₃⁻ in water into nitrogen (N₂) and simultaneously removes ammonium ions [...] Read more.

Nitrate ion (NO₃⁻) in wastewater is a major cause of pollution in aquatic environments worldwide. Magnetospirillum gryphiswaldense (MSR-1) has a complete dissimilatory denitrification pathway, converts NO₃⁻ in water into nitrogen (N₂) and simultaneously removes ammonium ions (NH₄⁺). We investigated and confirmed direct effects of regulatory protein factors Mg2046 and MgFnr on MSR-1 denitrification pathway by EMSAs and ChIP-qPCR assays. Corresponding mutant strains were constructed. Denitrification efficiency in synthetic wastewater medium during a 12-h cell growth period was significantly higher for mutant strain Δmgfnr (0.456 mmol·L⁻¹·h⁻¹) than for wild-type (0.362 mmol·L⁻¹·h⁻¹). Presence of magnetic particles (magnetosomes) in MSR-1 greatly facilitates collection and isolation of bacterial cells (and activated sludge) by addition of a magnetic field. The easy separation of magnetotactic bacteria, such as MSR-1 and Δmgfnr, from wastewater using magnetic fields is a unique feature that makes them promising candidates for practical application in wastewater treatment and sludge pretreatment. Full article

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12 pages, 2621 KiB

Open AccessArticle

Experiment on Influence of Blade Angle on Hydraulic Characteristics of the Shaft Tubular Pumping Device

by Kaihua Cheng, Songbai Li, Li Cheng, Tao Sun, Bowen Zhang and Weixuan Jiao

Processes 2022, 10(3), 590; https://doi.org/10.3390/pr10030590 - 17 Mar 2022

Cited by 5 | Viewed by 1695

Abstract

In order to understand the influence of blade angle on the hydraulic characteristics of a shaft tubular pumping device, the energy characteristics, cavitation characteristics, runaway characteristics, and pressure pulsation of the tubular pumping device under different blade angles were studied by a model [...] Read more.

In order to understand the influence of blade angle on the hydraulic characteristics of a shaft tubular pumping device, the energy characteristics, cavitation characteristics, runaway characteristics, and pressure pulsation of the tubular pumping device under different blade angles were studied by a model test. Comparing the efficiency of the best efficiency point of the pumping device under different blade angles, it can be seen that when the blade angle is +4°, the efficiency of the best efficiency point of the pumping device is the lowest, 74.10%. When the blade angle is −4°, the efficiency of the best efficiency point of the pumping device is the highest, 79.75%. Comparing the cavitation characteristics of the pumping device under different blade angles, it can be seen that when the blade angle is −4°, the overall cavitation performance of the pumping device is the best. When the design head point is deviated, the NPSH_av (Net positive suction head available) of the pump will increase. At the same blade angle, the runaway speed increases with the increase in head. The runaway speed of the prototype pump decreases with the increase in blade angle. When the blade angle is −6°, the runaway speed of the prototype pump is the largest, which is not conducive to the safe operation of the pumping station. When the blade angle is −4°, the variation law of pressure pulsation is small, and there is no abnormal pulsation. The tubular pumping device has satisfactory hydraulic performance, high efficiency, cavitation, and runaway characteristics. Therefore, the shaft tubular pumping device has wide application prospects under ultra-low head, and we recommend prioritizing it in low-head pumping stations. Full article

(This article belongs to the Special Issue Design and Optimization Method of Pumps)

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20 pages, 4678 KiB

Open AccessArticle

Modeling and Monitoring for Laminar Cooling Process of Hot Steel Strip Rolling with Time–Space Nature

by Qiang Wang, Kaixiang Peng and Jie Dong

Processes 2022, 10(3), 589; https://doi.org/10.3390/pr10030589 - 17 Mar 2022

Cited by 4 | Viewed by 4011

Abstract

The laminar cooling process is an important procedure in hot steel strip rolling. The spatial distribution and the drop curve of the strip temperature are crucial for the production and the quality of the steel strip. Traditionally, lumped parameter methods are often used [...] Read more.

The laminar cooling process is an important procedure in hot steel strip rolling. The spatial distribution and the drop curve of the strip temperature are crucial for the production and the quality of the steel strip. Traditionally, lumped parameter methods are often used for the modeling of the laminar cooling process, making it difficult to consider the impact of the variation of state variables and related parameters on the system, which seriously affect the stability of the steel strip quality. In this paper, a modeling and monitoring method with a time–space nature for the laminar cooling process is proposed to monitor the spatial variation of the strip temperature. Firstly, the finite-dimensional model is obtained by time–space separation to describe the temperature variation of the steel strip. Next, a global model is constructed by using the multi-modeling integration method. Then, a residual generator is designed to monitor the strip temperature where the statistics and the threshold are calculated. Finally, the superiority and reliability of the proposed method are verified by the actual-process data of the laminar cooling process for hot steel strip rolling, and different types of faults are detected successfully. Full article

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28 pages, 5616 KiB

Open AccessFeature PaperArticle

CFD Modelling of the Fuel Reactor of a Chemical Loping Combustion Plant to Be Used with Biomethane

by Pietro Bartocci, Alberto Abad, Arturo Cabello, Margarita de las Obras Loscertales, Wang Lu, Haiping Yang and Francesco Fantozzi

Processes 2022, 10(3), 588; https://doi.org/10.3390/pr10030588 - 17 Mar 2022

Cited by 4 | Viewed by 2103

Abstract

To realize a carbon negative power production technology, it is interesting the option of coupling a Chemical Loping Combustor to a gas turbine. The development of this technology foreseen in the project GTCLC-NEG has some technical barriers, the most important of which is [...] Read more.

To realize a carbon negative power production technology, it is interesting the option of coupling a Chemical Loping Combustor to a gas turbine. The development of this technology foreseen in the project GTCLC-NEG has some technical barriers, the most important of which is the operation of the chemical looping combustor at high temperature and high pressure conditions. To overcome these limits CFD modeling can be performed to optimize the behavior of the combustor and its design process. This work models the FUEL reactor of a chemical looping combustion plant working in batch mode and based on the reactor available at the Instituto de Carboquimica in Zaragoza, Spain. It is used an oxygen carrier mainly based on 60% mass Fe₂O₃ and 40% mass Al₂O₃. Biomethane is fed to the bottom of the fluidized bed with different velocities and mass flows and the composition of the gases at the outlet of the fuel reactor is measured. The results show that it is possible to model a 2 min duration reduction cycle by running the model for a time comprised between a minimum of 4 h and a maximum of 2 days of simulation. Another important result is the modeling of the chemical reactions happening in the reactor. Kinetics is modelled based on Activation energy (66 kJ/mol) and Pre-exponential factor (4.34 × 10¹ m³ⁿ mol⁻ⁿ s⁻¹). The simple kinetic scheme gives reasonable first approximations and can be used to determine the duration of the reaction, the composition of the exhaust gases and the biofuel conversion. Full article

(This article belongs to the Special Issue Current Trends in Anaerobic Digestion Processes)

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18 pages, 2267 KiB

Open AccessArticle

Spray-Dried Powder Containing Chitinase and β-1,3-Glucanase with Insecticidal Activity against Ceratitis capitata (Diptera: Tephritidae)

by Bruno C. Aita, Silvana Schmaltz, Alex Fochi, Vinícius F. Bolson, Thiarles Brun, Lucas de Arruda Cavallin, Gabriel Camatti, Dori E. Nava, Jerson V. C. Guedes, Raquel C. Kuhn, Giovani L. Zabot, Marcus Vinícius Tres and Marcio A. Mazutti

Processes 2022, 10(3), 587; https://doi.org/10.3390/pr10030587 - 17 Mar 2022

Cited by 3 | Viewed by 2492

Abstract

This study focused on obtaining a spray-dried powder containing chitinase and β-1,3-glucanase as active ingredients for the control of agricultural pests. Different carriers were tested in the spray drying of these enzymes. The effectiveness of the application of the enzymes was evaluated against [...] Read more.

This study focused on obtaining a spray-dried powder containing chitinase and β-1,3-glucanase as active ingredients for the control of agricultural pests. Different carriers were tested in the spray drying of these enzymes. The effectiveness of the application of the enzymes was evaluated against Ceratitis capitata (Diptera: Tephritidae). The combination of maltodextrin (2.5% w/v), gum Arabic (2.5% w/v), and soluble starch (5.0% w/v) as carriers showed the best result of residual activity of β-1,3-glucanase (88.36%) and chitinase (69.82%), with a powder recovery of 45.49%. The optimum conditions for the operational parameters of the spray drying process were: inlet air temperature of 120 °C, drying airflow rate of 1.1 m³/min, feed flow rate of 5.8 mL/min, and nozzle air pressure of 0.4 MPa. The powder produced showed 65.6% efficiency for the control of the fly. These results demonstrated the possibility of using the spray drying process to obtain an enzymatic potential product for biological pest control. Full article

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