Processes

15 pages, 6793 KiB

Open AccessFeature PaperArticle

Influence of Electrostatic Interactions During the Resorcinol-Formaldehyde Polymerization on the Characteristics of Mo-Doped Carbon Gels

by Sergio Morales-Torres, Hana Jirglová, Luisa M. Pastrana-Martínez and Francisco J. Maldonado-Hódar

Processes 2020, 8(6), 746; https://doi.org/10.3390/pr8060746 - 26 Jun 2020

Cited by 7 | Viewed by 2525

Abstract

The resorcinol (R)-formaldehyde (F) polymerization was carried out in different experimental conditions to obtain RF/Mo doped carbon xerogels with different morphology, porosity and nature and dispersion of metal. Attractive or repulsive electrostatic interactions were forced in the starting aqueous solution of RF-monomers using [...] Read more.

The resorcinol (R)-formaldehyde (F) polymerization was carried out in different experimental conditions to obtain RF/Mo doped carbon xerogels with different morphology, porosity and nature and dispersion of metal. Attractive or repulsive electrostatic interactions were forced in the starting aqueous solution of RF-monomers using different synthesis conditions, namely, combinations of cationic or anionic surfactants, Mo-precursors and pH values. The results showed that when both cationic surfactant and Mo-precursor were used at neutral pH, attractive interactions with the anionic RF-macromolecules are favored during polymerization and the final carbon xerogel exhibited the most developed porosity and the strongest Mo-organic phase interaction, leading to deeper Mo-phase reduction during carbonization and the formation of highly-dispersed crystalline nanoparticles of Mo₂C. On the contrary, the use of both anionic surfactant and Mo-precursor leads to repulsive interactions, which generates less porous carbon gels with a Mo-phase formed by large MoO₃ platelet structures and low Mo-surface contents. RF/Mo-doped gels with intermediate properties were obtained by combining cationic and anionic surfactants, metal precursors or both. After carbonization, the obtained materials would be suitable to be used directly as catalysts with different physicochemical properties and active phases. Full article

(This article belongs to the Special Issue Advances in Supported Nanoparticle Catalysts)

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16 pages, 1602 KiB

Open AccessConcept Paper

Designing the Next Generation of Fe⁰-Based Filters for Decentralized Safe Drinking Water Treatment: A Conceptual Framework

by Huichen Yang, Rui Hu, Arnaud Igor Ndé-Tchoupé, Willis Gwenzi, Hans Ruppert and Chicgoua Noubactep

Processes 2020, 8(6), 745; https://doi.org/10.3390/pr8060745 - 26 Jun 2020

Cited by 36 | Viewed by 4302

Abstract

The ambitious United Nations Sustainable Development Goal for 2030 to “leave no one behind” concerning safe drinking water calls for the development of universally applicable and affordable decentralized treatment systems to provide safe drinking water. Published results suggest that well-designed biological sand filters [...] Read more.

The ambitious United Nations Sustainable Development Goal for 2030 to “leave no one behind” concerning safe drinking water calls for the development of universally applicable and affordable decentralized treatment systems to provide safe drinking water. Published results suggest that well-designed biological sand filters (BSFs) amended with metallic iron (Fe⁰-BSFs) have the potential to achieve this goal. Fe⁰-BSFs quantitatively remove pathogens and a myriad of chemical pollutants. The available data were achieved under various operating conditions. A comparison of independent research results is almost impossible, especially because the used Fe⁰ materials are not characterized for their intrinsic reactivity. This communication summarizes the state-of-the-art knowledge on designing Fe⁰-BSFs for households and small communities. The results show that significant research progress has been made on Fe⁰-BSFs. However, well-designed laboratory and field experiments are required to improve the available knowledge in order to develop the next generation of adaptable and scalable designs of Fe⁰-BSFs in only two years. Tools to alleviate the permeability loss, the preferential flow, and the use of exhausted filters are presented. Full article

(This article belongs to the Section Environmental and Green Processes)

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18 pages, 4919 KiB

Open AccessArticle

Response Surface Optimization of Culture Conditions for Cyclic Lipopeptide MS07 from Bacillus siamensis Reveals Diverse Insights Targeting Antimicrobial and Antibiofilm Activity

by Md Maruf Khan, Young Kyun Kim, Seung Sik Cho, Ying-Yu Jin, Joo-Won Suh, Dae Young Lee and Jin Cheol Yoo

Processes 2020, 8(6), 744; https://doi.org/10.3390/pr8060744 - 26 Jun 2020

Cited by 12 | Viewed by 3952

Abstract

Efforts to isolate a broad-spectrum antimicrobial peptide (AMP) from microbial sources have been on the rise recently. Here, we report the identification, the optimization of the culture conditions, and the characterization of an efficient AMP from the Bacillus strain designated MS07 that exhibits [...] Read more.

Efforts to isolate a broad-spectrum antimicrobial peptide (AMP) from microbial sources have been on the rise recently. Here, we report the identification, the optimization of the culture conditions, and the characterization of an efficient AMP from the Bacillus strain designated MS07 that exhibits antimicrobial and antibiofilm activity. The production of MS07 was maximized by evaluating the culture conditions by the response surface methodology to obtain optimum media compositions. The biochemical integrity of MS07 was assessed by a bioassay indicating inhibition at ~6 kDa, like tricine-SDS-PAGE. MALDI-TOF confirmed the molecular weight and purity, showing a molecular mass of 6.099 kDa. Peptide MS07 exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. The MIC of MS07 for Escherichia coli, Alcaligenes faecalis, MRSA, and Pseudomonas aeruginosa ranged from 16–32 µg/mL, demonstrating superior potency. The biomass was diminished by about 15% and 11%, with rising concentrations up to 8 × MIC, for P. aeruginosa and E. coli biofilm, respectively. MS07 exhibited an 8 µM and 6 µM minimum bactericidal concentration against the biofilm of the Gram-negative strains P. aeruginosa and E. coli, respectively. Peptide MS07 reduced and interrupted the biofilm development in a concentration-dependent manner, as determined by BacLight live/dead staining using confocal microscopy. Full article

(This article belongs to the Special Issue Bioprocess Design and Optimization)

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Graphical abstract

23 pages, 1030 KiB

Open AccessArticle

Introducing Risk Considerations into the Supply Chain Network Design

by Ernest Benedito, Carme Martínez-Costa and Sergio Rubio

Processes 2020, 8(6), 743; https://doi.org/10.3390/pr8060743 - 26 Jun 2020

Cited by 9 | Viewed by 7188

Abstract

Supply chains (SC) aim to provide products to the final customer at a certain service level. However, unforeseen events occur that impede supply chain objectives. SC Risk has been studied in the literature, providing frameworks and methodologies to manage SC failures. Nevertheless, more [...] Read more.

Supply chains (SC) aim to provide products to the final customer at a certain service level. However, unforeseen events occur that impede supply chain objectives. SC Risk has been studied in the literature, providing frameworks and methodologies to manage SC failures. Nevertheless, more efforts are needed to prevent hazardous and disruptive risks and their consequences. These risks must be considered during the process of designing a supply chain. Some methodological contributions concerning risk in the supply chain network design (SCND) are conceptual frameworks for mitigating SC disruptions, which suggest strategies and measures for designing robust and resilient SCs. Although such contributions are valuable, they do not indicate how to cope with risk when designing a SC. The main objective of this research is to describe a methodology aimed at including risk considerations into the SCND. Our proposal aims to be, on the one hand, a comprehensive approach that includes a risk identification and assessment procedure in each of the stages of the SCND process and, on the other hand, a tool for decision-making in SC design or redesign processes when SC risks need to be considered. The methodology proposed is an extension of a SCND methodology including risk considerations in order to improve the performance of the supply chains. A case study illustrates how the proposed methodological works, achieving the identification of SC risks already observed in previous works. Full article

(This article belongs to the Special Issue Advances in Sustainable Supply Chains)

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15 pages, 7332 KiB

Open AccessArticle

Thermophysical Properties of Newly Synthesized Ammonium-Based Protic Ionic Liquids: Effect of Temperature, Anion and Alkyl Chain Length

by Nur Hidayah Zulaikha Othman Zailani, Normawati M. Yunus, Asyraf Hanim Ab Rahim and Mohamad Azmi Bustam

Processes 2020, 8(6), 742; https://doi.org/10.3390/pr8060742 - 25 Jun 2020

Cited by 22 | Viewed by 3000

Abstract

Ionic liquids which are often classified as low melting point salts have received significant attention from research groups and industries to be used in a wide range of applications. Many of these applications require thorough knowledge on the thermophysical properties of the ionic [...] Read more.

Ionic liquids which are often classified as low melting point salts have received significant attention from research groups and industries to be used in a wide range of applications. Many of these applications require thorough knowledge on the thermophysical properties of the ionic liquids before utilizing their full potentials in various fields. In this work, a series of alkylammonium cation and carboxylate anion-based room temperature protic ionic liquids (PILs) were synthesized by varying length of alkyl chain of the cation from diethyl to dibutyl combined with pentanoate, hexanoate and heptanoate anions. These ammonium-based PILs named as diethylammonium pentanoate [DEA][C5], diethylammonium hexanoate [DEA][C6], diethylammonium heptanoate [DEA][C7], dibutylammonium pentanoate [DBA][C5], dibutylammonium hexanoate [DBA][C6] and dibutylammonium heptanoate [DBA][C7] were characterized using Nuclear Magnetic Resonance (NMR) spectroscopy. The thermophysical properties of the PILs namely density, dynamic viscosity and refractive index were measured and analyzed. Density, ρ and dynamic viscosity, η were determined at T = (293.15 to 363.15) K and refractive index, n_D was measured at T = (293.15 to 333.15) K. The fitting parameters are proposed for the empirical correlations of density, dynamic viscosity and refractive index. The values of thermal expansion coefficient, α_p, molecular volume, V_m, standard entropy, S° and lattice potential energy, U_pot also have been calculated by using the specified equations. The thermal decomposition temperature, T_d was also determined using a thermogravimetric analyzer (TGA) while the differential scanning calorimetry (DSC) technique provided the glass transition, T_g, melting point, T_m and crystallization, T_c temperatures of the PILs. The experimental results revealed that the dependency of the experimental values namely the ρ, η, n_D, and T_d on the alkyl chain of the anion, size of the cations and the temperature of measurement. Full article

(This article belongs to the Special Issue Sustainable Modelling, Processes and Applications for Societal Development)

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13 pages, 2439 KiB

Open AccessArticle

Analysis of Oil Droplet Deposition Characteristics and Determination of Impact State Criterion in Aero-Engine Bearing Chamber

by Fei Wang, Lin Wang and Guoding Chen

Processes 2020, 8(6), 741; https://doi.org/10.3390/pr8060741 - 25 Jun 2020

Cited by 5 | Viewed by 2821

Abstract

The research of oil/air two-phase flow and heat transfer is the fundamental work of the design of lubrication and heat transfer in aero-engine bearing chamber. The determination of impact state criterion of the moving oil droplets with the wall and the analysis of [...] Read more.

The research of oil/air two-phase flow and heat transfer is the fundamental work of the design of lubrication and heat transfer in aero-engine bearing chamber. The determination of impact state criterion of the moving oil droplets with the wall and the analysis of oil droplet deposition characteristics are important components. In this paper, the numerical analysis model of the impact between the moving oil droplet and the wall is established by using the finite volume method, and the simulation of oil droplet impingement on the wall is carried out. Then the effects of oil droplet diameter, impact velocity, and incident angle on the characteristic parameters of impact state are discussed. The characteristic parameters include the maximum spreading length, the maximum spreading width, and the number of splashing oil droplets. Lastly the calculation results are verified through comparing with the experimental results in the literature. The results show as follows: (1) The maximum spreading width of oil droplet firstly increases and then slows down with the incident angle and the oil droplet diameter increasing; (2) when the oil droplet diameter becomes small, the influence of the incident angle on the maximum spreading length of oil droplet is obvious and vice versa; (3) with the impact velocity and diameter of oil droplet increasing, the maximum spreading width of oil droplet increases firstly and then slows down, and the maximum spreading length increased gradually; (4) the number of splashing oil droplets increases with the incident angle and impact velocity increasing; and (5) compared with the experimental data in literature, the critical dimensionless splashing coefficient

K c

proposed in this paper can better distinguish the impact state of oil droplet. Full article

(This article belongs to the Special Issue CFD Applications in Energy Engineering Research and Simulation)

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11 pages, 855 KiB

Open AccessArticle

Ranking Factors of Infant Formula Milk Powder Using Improved Entropy Weight Based on HDT Method and Its Application of Food Safety

by Qunxiong Zhu and Lu Liu

Processes 2020, 8(6), 740; https://doi.org/10.3390/pr8060740 - 25 Jun 2020

Cited by 5 | Viewed by 3424

Abstract

Food safety is about everyone’s health. Through risk assessment and early warning of food safety, food-related safety issues can be identified as early as possible and take timely precautions. However, the detection data of food safety are complex and non-linear, so it is [...] Read more.

Food safety is about everyone’s health. Through risk assessment and early warning of food safety, food-related safety issues can be identified as early as possible and take timely precautions. However, the detection data of food safety are complex and non-linear, so it is necessary to find the relationship and hierarchical representation of factors affecting food safety. This paper presents an improved entropy weight based on Hasse diagram technology (HDT) method to analyze the influencing factors of food safety. The entropy weight method was used to calculate the weight of each factor index, and the relationship matrix was obtained. Then, the data of infant milk powder in China were analyzed hierarchically by the HDT method. Thus, we can obtain the multi-level structure that affects food safety. It provides an effective basis for early warning of food safety, can help government regulators to strengthen management, and urge enterprises to produce food safely. Full article

(This article belongs to the Collection Sustainable Food Processing Processes)

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10 pages, 2153 KiB

Open AccessFeature PaperArticle

Heterotrophic Plate Count for Bottled Water Safety Management

by Anna Rygala, Joanna Berlowska and Dorota Kregiel

Processes 2020, 8(6), 739; https://doi.org/10.3390/pr8060739 - 24 Jun 2020

Cited by 8 | Viewed by 7063

Abstract

Heterotrophic bacteria are able to form biofilms in water processing systems, adhering to pipe materials and colonizing surfaces. The aim of our research was to identify the critical points in the process of bottled water production at which controls can be applied to [...] Read more.

Heterotrophic bacteria are able to form biofilms in water processing systems, adhering to pipe materials and colonizing surfaces. The aim of our research was to identify the critical points in the process of bottled water production at which controls can be applied to prevent, reduce, or eliminate water safety hazards. Microbiological monitoring was conducted using the plate count method and luminometry. To identify the bacterial isolates, we used polyphasic identification based on biochemical tests and molecular analysis using ribosomal RNA. The heterotrophic plate counts were higher in the water filtration station, ultrafiltration (UV) disinfection station, and holding tank. At these points of the industrial process, the water is stagnant or there is poor flow. Molecular analysis identified the bacterial isolates as belonging to Acinetobacter, Agrobacterium, Aeromonas, Brevundimonas, Citrobacter, Enterobacter, Klebsiella, Pantoea, and Rhizobium genera. Bacterial isolates showed various levels of biofilm formation, and the best adhesion properties were exhibited by the Aeromonas hydrophila and Citrobacter freundii strains. Full article

(This article belongs to the Special Issue Processing Foods: Process Optimization and Quality Assessment)

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13 pages, 2497 KiB

Open AccessArticle

Kinetics of Alkyl Lactate Formation from the Alcoholysis of Poly(Lactic Acid)

by Fabio M. Lamberti, Luis A. Román-Ramírez, Paul Mckeown, Matthew D. Jones and Joseph Wood

Processes 2020, 8(6), 738; https://doi.org/10.3390/pr8060738 - 24 Jun 2020

Cited by 13 | Viewed by 4049

Abstract

Alkyl lactates are green solvents that are successfully employed in several industries such as pharmaceutical, food and agricultural. They are considered prospective renewable substitutes for petroleum-derived solvents and the opportunity exists to obtain these valuable chemicals from the chemical recycling of waste poly(lactic [...] Read more.

Alkyl lactates are green solvents that are successfully employed in several industries such as pharmaceutical, food and agricultural. They are considered prospective renewable substitutes for petroleum-derived solvents and the opportunity exists to obtain these valuable chemicals from the chemical recycling of waste poly(lactic acid). Alkyl lactates (ethyl lactate, propyl lactate and butyl lactate) were obtained from the catalysed alcoholysis reaction of poly(lactic acid) with the corresponding linear alcohol. Reactions were catalysed by a Zn complex synthesised from an ethylenediamine Schiff base. The reactions were studied in the 50–130 °C range depending on the alcohol, at autogenous pressure. Arrhenius temperature-dependent parameters (activation energies and pre-exponential factors) were estimated for the formation of the lactates. The activation energies (Ea₁, Ea₂ and Ea₋₂) for alcoholysis in ethanol were 62.58, 55.61 and 54.11 kJ/mol, respectively. Alcoholysis proceeded fastest in ethanol in comparison to propanol and butanol and reasonable rates can be achieved in temperatures as low as 50 °C. This is a promising reaction that could be used to recycle end-of-life poly(lactic acid) and could help create a circular production economy. Full article

(This article belongs to the Section Environmental and Green Processes)

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17 pages, 4660 KiB

Open AccessArticle

Optimal Scheduling of Island Microgrid with Seawater-Pumped Storage Station and Renewable Energy

by Ning Liang, Pengcheng Li, Zhijian Liu, Qi Song and Linlin Luo

Processes 2020, 8(6), 737; https://doi.org/10.3390/pr8060737 - 24 Jun 2020

Cited by 7 | Viewed by 2348

Abstract

The rapid development of renewable energy, represented by wind and photovoltaic, provides a new solution for island power supplies. However, due to the intermittent and random nature of renewable energy, a microgrid needs energy-storage components to stabilize its power supply when coupled with [...] Read more.

The rapid development of renewable energy, represented by wind and photovoltaic, provides a new solution for island power supplies. However, due to the intermittent and random nature of renewable energy, a microgrid needs energy-storage components to stabilize its power supply when coupled with them. The emergence of seawater-pumped storage stations provides a new method to offset the shortage of island power supply. In this study, an optimal scheduling of island microgrid is proposed, which uses seawater-pumped storage station as the energy storage equipment to cooperate with wind, photovoltaic and diesel generator. First, a mathematic formulation of seawater-pumped storage station with renewable energy is presented. Then, to reach the goal of economic dispatch, an optimal scheduling model of island microgrid is established with the consideration of both respective operation constraints and island load requirements. Finally, the effectiveness of the proposed model is verified by an island microgrid over two typical seasons. The simulation results show that the proposed framework not only increases the usage of renewable energy, but also improves the operational reliability and economy of island microgrids. Full article

(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)

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18 pages, 2532 KiB

Open AccessArticle

Screening of Different Ageing Technologies of Wine Spirit by Application of Near-Infrared (NIR) Spectroscopy and Volatile Quantification

by Ofélia Anjos, Ilda Caldeira, Rita Roque, Soraia I. Pedro, Sílvia Lourenço and Sara Canas

Processes 2020, 8(6), 736; https://doi.org/10.3390/pr8060736 - 24 Jun 2020

Cited by 19 | Viewed by 3040

Abstract

The traditional ageing of wine spirits is done in wooden barrels, however, high costs have led to the search for alternative technologies, such as the use of stainless steel tanks with wooden staves and the application of micro-oxygenation. This work evaluates the changes [...] Read more.

The traditional ageing of wine spirits is done in wooden barrels, however, high costs have led to the search for alternative technologies, such as the use of stainless steel tanks with wooden staves and the application of micro-oxygenation. This work evaluates the changes in the major volatile compounds of wine spirits aged for 6, 12 and 18 months in wooden barrels and stainless steel tanks with micro-oxygenation. For both ageing technologies, two types of wood (Limousin oak and Portuguese chestnut wood) were used. The samples were analysed concerning their alcohol strength (electronic densimetry) and volatile composition, namely of methanol, acetaldehyde, ethyl acetate and other major volatile compounds ((GC-FID) and near-infrared spectroscopy (NIR)). The results show that the ageing technology was more influential than the wood species for the volatile composition of wine spirits, namely acetaldedehyde, methanol, 2-methylpropan-1-ol and 2+3-methylbutan-1-ol. However, the opposite behaviour was found for the spectral data. The ageing process was accelerated by using the alternative ageing technology, especially with chestnut wood staves. The most informative spectral regions to discriminate samples were around 6859 cm⁻¹ and from 5200 cm⁻¹ to 4200 cm⁻¹. NIR is a promising technique to identify different technologies and different wood species used in the ageing process of wine spirits. Full article

(This article belongs to the Section Food Process Engineering)

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14 pages, 3133 KiB

Open AccessFeature PaperArticle

Evaluation of a Novel Polymeric Flocculant for Enhanced Water Recovery of Mature Fine Tailings

by Kyle C. Lister, Heather Kaminsky and Robin A. Hutchinson

Processes 2020, 8(6), 735; https://doi.org/10.3390/pr8060735 - 24 Jun 2020

Cited by 7 | Viewed by 2942

Abstract

The novel cationic flocculant, poly(lactic acid) choline iodide ester methacrylate (poly(PLA₄ChMA)), has been shown to provide improved flocculation of 5.0 wt.% mature fine tailings (MFT) diluted in deionized water compared to commercial anionic polymers, with continued dewatering of the sediment occurring [...] Read more.

The novel cationic flocculant, poly(lactic acid) choline iodide ester methacrylate (poly(PLA₄ChMA)), has been shown to provide improved flocculation of 5.0 wt.% mature fine tailings (MFT) diluted in deionized water compared to commercial anionic polymers, with continued dewatering of the sediment occurring as the polymer undergoes partial hydrolytic degradation. However, the elevated dosages (10,000 ppm) required would make the polymer costly to implement on an industrial scale. With this motivation, the impact of MFT loading and the use of process water is explored while comparing the settling performance of poly(PLA₄ChMA) to available commercial alternatives such as anionic FLOPAM A3338. Improved consolidation of 5.0 wt.% MFT diluted with process water could be achieved at reduced dosages (500 ppm) with poly(PLA₄ChMA). However, the final compaction levels after polymer degradation were similar to those achieved with the nondegradable commercial flocculants. Flocculation-filtration experiments with undiluted MFT are also conducted to compare the performance of the polymers. Significantly faster rates of water release were observed with the cationic flocculants compared to FLOPAM A3338, but no improvement in the overall tailings compaction was found either before or after poly(PLA₄ChMA) degradation. Thus, the improved dewatering observed with poly(PLA₄ChMA) in dilute MFT suspensions does not extend to conditions that would be encountered in the field. Full article

(This article belongs to the Special Issue Design and Applications of Polymeric Flocculants)

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26 pages, 2262 KiB

Open AccessReview

Approaches in Design of Laboratory-Scale UASB Reactors

by Yehor Pererva, Charles D. Miller and Ronald C. Sims

Processes 2020, 8(6), 734; https://doi.org/10.3390/pr8060734 - 24 Jun 2020

Cited by 11 | Viewed by 9905

Abstract

Up-flow Anaerobic Sludge Blanket (UASB) reactors are popular tools in wastewater treatment systems due to the ability to work with high feed rates and wastes with high concentration of organic contaminants. While full-scale industrial applications of UASB reactors are developed and described in [...] Read more.

Up-flow Anaerobic Sludge Blanket (UASB) reactors are popular tools in wastewater treatment systems due to the ability to work with high feed rates and wastes with high concentration of organic contaminants. While full-scale industrial applications of UASB reactors are developed and described in the available literature, laboratory-scale designs utilized for treatability testing are not well described. The majority of published studies do not describe the laboratory UASB construction details or do use reactors that already had developed a trophic network in microbial consortia under laboratory environment and therefore are more stable. The absence of defined guidelines for geometry design, selection of materials, construction, operation rules, and, especially, the start-up conditions, significantly hamper researchers who desire to conduct treatability testing using UASB reactors in laboratory scale. In this article, we compiled and analyzed the information available in the refereed literature concerning UASB reactors used in laboratory environment, where information on geometry and/or operational conditions were provided in detail. We utilized the information available in the literature and the experience gained in our laboratory (Sustainable Waste to Bioproducts Engineering Center) to suggest a unified operation flowchart and for design, construction, operation, and monitoring for a laboratory-scale UASB reactors. Full article

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

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12 pages, 3034 KiB

Open AccessFeature PaperArticle

Characterization of Licorice Root Waste for Prospective Use as Filler in more Eco-Friendly Composite Materials

by Carlo Santulli, Marco Rallini, Debora Puglia, Serena Gabrielli, Luigi Torre and Enrico Marcantoni

Processes 2020, 8(6), 733; https://doi.org/10.3390/pr8060733 - 24 Jun 2020

Cited by 13 | Viewed by 4006

Abstract

The extraction of glycyrrhizin from licorice root and stolon with ethanol/water solutions leaves a lignocellulosic residue, which could be potentially applied in biocomposites. This process proved difficult in principle, given the considerable hardness of this material as received, which impedes its use in [...] Read more.

The extraction of glycyrrhizin from licorice root and stolon with ethanol/water solutions leaves a lignocellulosic residue, which could be potentially applied in biocomposites. This process proved difficult in principle, given the considerable hardness of this material as received, which impedes its use in polymer resins in large amounts. After ball milling, up to 10% of this fibrous residue, which shows very variable aspect ratio, was introduced into an epoxy matrix, to investigate its possible future application in sustainable polymers. Of the three composites investigated, containing 1, 5 and 10 wt% of licorice waste, respectively, by performing flexural testing, it was found that the introduction of an intermediate amount of filler proved the most suitable for possible development. Thermal characterization by thermogravimetry (TGA) did not indicate large variation of degradation properties due to the introduction of the filler. Despite the preliminary characteristics of this study, an acceptable resin-filler interface has been obtained for all filler contents. Issues to be solved in future study would be the possibility to include a larger amount of filler by better compatibilization and a more uniform distribution of the filler, considering their orientation, since most of it maintains an elongated geometry after ball milling. Full article

(This article belongs to the Special Issue Synthesis and Applications of Eco-Friendly Polymers)

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14 pages, 1735 KiB

Open AccessFeature PaperArticle

Application of Combined Developments in Processes and Models to the Determination of Hot Metal Temperature in BOF Steelmaking

by José Díaz and Francisco Javier Fernández

Processes 2020, 8(6), 732; https://doi.org/10.3390/pr8060732 - 24 Jun 2020

Cited by 4 | Viewed by 3142

Abstract

Nowadays, the steel industry is seeking to reduce its carbon footprint without affecting productivity or profitability. This challenge needs to be supported by continuous improvements in equipment, methods, sensors and models. The present work exposes how the combined development of processes and models [...] Read more.

Nowadays, the steel industry is seeking to reduce its carbon footprint without affecting productivity or profitability. This challenge needs to be supported by continuous improvements in equipment, methods, sensors and models. The present work exposes how the combined development of processes and models (CDPM) has been applied to the improvement of hot metal temperature determination. The synergies that arise when both sides of this research are simultaneously approached are evidenced. A workflow that takes into account the CDPM approach is proposed. First, a thermal model of the process is developed, making it possible to identify that hot metal temperature is a key lever for carbon footprint reduction. Then, three main alternatives for hot metal temperature determination are compared: infrared thermometry, time-series forecasting and machine learning prediction. Despite considering only few process variables, machine learning techniques succeed in extracting relevant information from process databases. An accuracy close to infrared thermometry is obtained, with a much higher applicability. This research shows that process-model alternatives are complementary when judiciously nested in the process computer routines. Combining measurement and modelling techniques, 100% applicability is achieved with an error reduction of 7 °C. Full article

(This article belongs to the Special Issue Synergies in Combined Development of Processes and Models)

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20 pages, 5577 KiB

Open AccessArticle

Development of Test Procedures Based on Chaotic Advection for Assessing Polymer Performance in High-Solids Tailings Applications

by Allan Costine, Phillip Fawell, Andrew Chryss, Stuart Dahl and John Bellwood

Processes 2020, 8(6), 731; https://doi.org/10.3390/pr8060731 - 24 Jun 2020

Cited by 4 | Viewed by 3097

Abstract

Post-thickener polymer addition to initiate rapid tailings dewatering has gained considerable interest for tailings storage facility (TSF) management. However, the highly viscous and non-Newtonian rheology of dense suspensions presents unique challenges for mixing with polymer solutions. Such mixing is highly inefficient, often resulting [...] Read more.

Post-thickener polymer addition to initiate rapid tailings dewatering has gained considerable interest for tailings storage facility (TSF) management. However, the highly viscous and non-Newtonian rheology of dense suspensions presents unique challenges for mixing with polymer solutions. Such mixing is highly inefficient, often resulting in polymer overdosing and wide variations in deposited tailings characteristics, with the potential to significantly compromise TSF performance. In this study, a new type of mixer based on the principles of chaotic advection was used for treating kaolin suspensions with high molecular weight (MW) anionic copolymer solutions. Chaotic advection imparts efficient mixing by gently stretching and folding flows in a controlled manner, as opposed to random, high-shear flows associated with turbulent mixing, and this lower shear stress allows for the controlled formation of larger aggregate structures with vastly improved dewatering characteristics. A pre-conditioning pipe reactor prior to this mixer can also be advantageous in terms of providing a short burst of high shear for initial polymer distribution. Seven acrylamide/acrylate copolymers of a fixed anionic charge density (30%) spanning a distinct MW range, as characterized by intrinsic viscosity, were applied at elevated dosages to high-solids (20–30 wt %) kaolin suspensions in continuous flow through the chaotic mixer described above. Medium-to-high MW polymers were generally preferred, with further increases in MW resulting in significantly diminished dewatering outcomes. Direct analysis of polymer solution properties through oscillatory rheology gave a better indication of a polymer’s potential performance compared with intrinsic viscosity, offering a more robust basis for polymer selection. This represented the first systematic study into the effects of polymer properties on deposition behavior after dosing at high solids, which was only possible through the ability to apply controlled shear across the entire suspension during sample preparation. Full article

(This article belongs to the Special Issue Design and Applications of Polymeric Flocculants)

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16 pages, 5353 KiB

Open AccessArticle

Research on Combustion Characteristics of Air–Light Hydrocarbon Mixing Gas

by Zhiqun Meng, Jinggang Wang, Chuchao Xiong, Jiawen Qi and Liquan Hou

Processes 2020, 8(6), 730; https://doi.org/10.3390/pr8060730 - 24 Jun 2020

Cited by 3 | Viewed by 3010

Abstract

Air–light hydrocarbon mixing gas is a new type of city gas which is composed of light hydrocarbon with the main component of n-pentane and air mixed in a certain proportion. To explore the dominant reactions for CO production of air–light hydrocarbon mixing [...] Read more.

Air–light hydrocarbon mixing gas is a new type of city gas which is composed of light hydrocarbon with the main component of n-pentane and air mixed in a certain proportion. To explore the dominant reactions for CO production of air–light hydrocarbon mixing gas with different mixing degrees at the critical equivalence ratios, a computational study was conducted on the combustion characteristics, including the ignition delay time, laminar flame speed, extinction residence time, and emission of air–light hydrocarbon mixing gas at atmospheric pressure and room temperature in the present study. The calculated results indicate that the ignition delay time of air–light hydrocarbon mixing gas at temperatures of 1000–1118 K is greater than that of n-pentane, while the opposite at temperatures of 1118–1600 K. From the study of the laminar flame speed and ignition delay time, it was found that the essence of air–light hydrocarbon mixing gas is that its attribute parameter is determined by the ratio of n-pentane to the total amount of air at the moment of combustion. The changes in the extinction residence time and the CO emission index of air–light hydrocarbon mixing gas are not synchronized, that is the CO emission index is not necessarily small for air–light hydrocarbon mixing gas with excellent extinction residence time. CO sensitivity analysis and CO rate of production identified key species and reactions that are primarily responsible for CO formation and annihilation. The mixing degree plays a key role in the CO emission index of air–light hydrocarbon mixing gas, which has a constructive opinion on the future experiment and application of air–light hydrocarbon mixing gas. Full article

(This article belongs to the Special Issue Progress in Energy Conversion Systems and Emission Control)

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24 pages, 19038 KiB

Open AccessArticle

The Neural Network Revamping the Process’s Reliability in Deep Lean via Internet of Things

by Ahmed M. Abed, Samia Elattar, Tamer S. Gaafar and Fadwa Moh. Alrowais

Processes 2020, 8(6), 729; https://doi.org/10.3390/pr8060729 - 23 Jun 2020

Cited by 10 | Viewed by 2593

Abstract

Deep lean is a novel approach that is concerned with the profound analysis for waste’s behavior at hidden layers in manufacturing processes to enhance processes’ reliability level at the upstream. Ideal Standard Co. for bathtubs suffered from defects and cost losses in the [...] Read more.

Deep lean is a novel approach that is concerned with the profound analysis for waste’s behavior at hidden layers in manufacturing processes to enhance processes’ reliability level at the upstream. Ideal Standard Co. for bathtubs suffered from defects and cost losses in the spraying section, due to differences in the painting cover thickness due to bubbles, caused by eddies, which move toward the bathtubs through hoses. These bubbles and their movement are considered as a form of lean’s waste. The spraying liquid inside the tanks and hoses must move with uniform velocity, viscosity, pressure, feed rate and suitable Reynolds circulation values to eliminate the eddy causes. These factors are tackled through the adoption Internet of Things (IoT) technologies that are aided by neural networks (NN) when an abnormal flow rate is detected using sensor data in real-time that can reduce the defects. The NN aimed at forecasting eddies’ movement lines that carry bubbles and works on being blasted before entering the hoses through using Design of Experiment (DOE). This paper illustrates a deep lean perspective as driven by the define, measure, analysis, improvement and control (DMAIC) methodology to improve reliability. The eddy moves downstream slowly with an anti-clockwise flow for some of the optimal values for the influencing factors, whereas the circulation of Ω increases, whether for vertical or horizontal travel. Full article

(This article belongs to the Special Issue Control and Optimization of Multi-Agent Systems and Complex Networks for Systems Engineering)

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19 pages, 6221 KiB

Open AccessArticle

Image-Based Model for Assessment of Wood Chip Quality and Mixture Ratios

by Thomas Plankenbühler, Sebastian Kolb, Fabian Grümer, Dominik Müller and Jürgen Karl

Processes 2020, 8(6), 728; https://doi.org/10.3390/pr8060728 - 23 Jun 2020

Cited by 11 | Viewed by 2653

Abstract

This article focuses on fuel quality in biomass power plants and describes an online prediction method based on image analysis and regression modeling. The main goal is to determine the mixture fraction from blends of two wood chip species with different qualities and [...] Read more.

This article focuses on fuel quality in biomass power plants and describes an online prediction method based on image analysis and regression modeling. The main goal is to determine the mixture fraction from blends of two wood chip species with different qualities and properties. Starting from images of both fuels and different mixtures, we used two different approaches to deduce feature vectors. The first one relied on integral brightness values while the latter used spatial texture information. The features were used as input data for linear and non-linear regression models in nine training classes. This permitted the subsequent prediction of mixture ratios from prior unknown similar images. We extensively discuss the influence of model and image selection, parametrization, the application of boosting algorithms and training strategies. We obtained models featuring predictive accuracies of R² > 0.9 for the brightness-based model and R² > 0.8 for the texture based one during the validation tests. Even when reducing the data used for model training down to two or three mixture classes—which could be necessary or beneficial for the industrial application of our approach—sampling rates of n < 5 were sufficient in order to obtain significant predictions. Full article

(This article belongs to the Special Issue Progress in Energy Conversion Systems and Emission Control)

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Graphical abstract

18 pages, 8254 KiB

Open AccessArticle

Condensate-Banking Removal and Gas-Production Enhancement Using Thermochemical Injection: A Field-Scale Simulation

by Amjed Hassan, Mohamed Abdalla, Mohamed Mahmoud, Guenther Glatz, Abdulaziz Al-Majed and Ayman Al-Nakhli

Processes 2020, 8(6), 727; https://doi.org/10.3390/pr8060727 - 23 Jun 2020

Cited by 8 | Viewed by 4268

Abstract

Condensate-liquid accumulation in the vicinity of a well is known to curtail gas production up to 80%. Numerous approaches are employed to mitigate condensate banking and improve gas productivity. In this work, a field-scale simulation is presented for condensate damage removal in tight [...] Read more.

Condensate-liquid accumulation in the vicinity of a well is known to curtail gas production up to 80%. Numerous approaches are employed to mitigate condensate banking and improve gas productivity. In this work, a field-scale simulation is presented for condensate damage removal in tight reservoirs using a thermochemical treatment strategy where heat and pressure are generated in situ. The impact of thermochemical injection on the gas recovery is also elucidated. A compositional simulator was utilized to assess the effectiveness of the suggested treatment on reducing the condensate damage and, thereby, improve the gas recovery. Compared to the base case, represented by an industry-standard gas injection strategy, simulation studies suggest a significantly improved hydrocarbon recovery performance upon thermochemical treatment of the near-wellbore zone. For the scenarios investigated, the application of thermochemicals allowed for an extension of the production plateau from 104 days, as determined for the reference gas injection case, to 683 days. This represents a 6.5-fold increase in production plateau time, boosting gas recovery from 25 to 89%. The improved recovery is attributed to the reduction of both capillary pressure and condensate viscosity. The presented work is crucial for designing and implementing thermochemical treatments in tight-gas reservoirs. Full article

(This article belongs to the Section Energy Systems)

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16 pages, 6708 KiB

Open AccessFeature PaperArticle

Sustainable Water Responsive Mechanically Adaptive and Self-Healable Polymer Composites Derived from Biomass

by Pranabesh Sahu and Anil K. Bhowmick

Processes 2020, 8(6), 726; https://doi.org/10.3390/pr8060726 - 22 Jun 2020

Cited by 5 | Viewed by 2526

Abstract

New synthetic biobased mechanically adaptive composites, responding to water and having self-healing property, were developed. These composites were prepared by introducing plant-based cellulose nanofibrils (CNFs) at 10, 20, and 25% (v/v) concentration into a biobased rubbery poly (myrcene-co [...] Read more.

New synthetic biobased mechanically adaptive composites, responding to water and having self-healing property, were developed. These composites were prepared by introducing plant-based cellulose nanofibrils (CNFs) at 10, 20, and 25% (v/v) concentration into a biobased rubbery poly (myrcene-co-furfuryl methacrylate) (PMF) matrix by solution mixing and subsequent compression molding technique. The reinforcement of CNFs led to an increase in the tensile storage modulus (E’) of the dry composites. Upon exposure to water, water sensitivity and a drastic fall in storage moduli (E’) were observed for the 25% (v/v) CNF composite. A modulus reduction from 1.27 (dry state) to 0.15 MPa (wet state) was observed for this composite. The water-sensitive nature of the composites was also confirmed from the force modulation study in atomic force microscopy (AFM), revealing the average modulus as 82.7 and 32.3 MPa for dry and swollen composites, respectively. Interestingly, the composites also showed thermoreversibility and excellent healing property via Diels-Alder (DA) click chemistry using bismaleimide as a crosslinker, when the scratched samples were heated at 120 °C (rDA) for 10 h and then cooled down to 60 °C (DA) followed by room temperature. The healing efficiency was obtained as about 90% from the AFM 3D height images. Thus, the composites exhibited dual stimuli-responsive behavior as mechanically adaptive water sensitive polymers with water as the stimulus and self-healing polymer using bismaleimide as an external stimulus. Therefore, this study provides guidance and new frontiers to make use of composite materials based on biopolymers for various potential smart and biomedical applications. Full article

(This article belongs to the Special Issue Green Synthesis Processes of Polymers & Composites)

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15 pages, 2206 KiB

Open AccessArticle

MPPIF-Net: Identification of Plasmodium Falciparum Parasite Mitochondrial Proteins Using Deep Features with Multilayer Bi-directional LSTM

by Samee Ullah Khan and Ran Baik

Processes 2020, 8(6), 725; https://doi.org/10.3390/pr8060725 - 22 Jun 2020

Cited by 30 | Viewed by 3272

Abstract

Mitochondrial proteins of Plasmodium falciparum (MPPF) are an important target for anti-malarial drugs, but their identification through manual experimentation is costly, and in turn, their related drugs production by pharmaceutical institutions involves a prolonged time duration. Therefore, it is highly desirable for pharmaceutical [...] Read more.

Mitochondrial proteins of Plasmodium falciparum (MPPF) are an important target for anti-malarial drugs, but their identification through manual experimentation is costly, and in turn, their related drugs production by pharmaceutical institutions involves a prolonged time duration. Therefore, it is highly desirable for pharmaceutical companies to develop computationally automated and reliable approach to identify proteins precisely, resulting in appropriate drug production in a timely manner. In this direction, several computationally intelligent techniques are developed to extract local features from biological sequences using machine learning methods followed by various classifiers to discriminate the nature of proteins. Unfortunately, these techniques demonstrate poor performance while capturing contextual features from sequence patterns, yielding non-representative classifiers. In this paper, we proposed a sequence-based framework to extract deep and representative features that are trust-worthy for Plasmodium mitochondrial proteins identification. The backbone of the proposed framework is MPPF identification-net (MPPFI-Net), that is based on a convolutional neural network (CNN) with multilayer bi-directional long short-term memory (MBD-LSTM). MPPIF-Net inputs protein sequences, passes through various convolution and pooling layers to optimally extract learned features. We pass these features into our sequence learning mechanism, MBD-LSTM, that is particularly trained to classify them into their relevant classes. Our proposed model is experimentally evaluated on newly prepared dataset PF2095 and two existing benchmark datasets i.e., PF175 and MPD using the holdout method. The proposed method achieved 97.6%, 97.1%, and 99.5% testing accuracy on PF2095, PF175, and MPD datasets, respectively, which outperformed the state-of-the-art approaches. Full article

(This article belongs to the Special Issue Bioinformatics Applications Based On Machine Learning)

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13 pages, 3871 KiB

Open AccessFeature PaperArticle

Biochar as an Effective Filler of Carbon Fiber Reinforced Bio-Epoxy Composites

by Danuta Matykiewicz

Processes 2020, 8(6), 724; https://doi.org/10.3390/pr8060724 - 22 Jun 2020

Cited by 50 | Viewed by 8357

Abstract

The goal of this work was to investigate the effect of the biochar additive (2.5; 5; 10 wt.%) on the properties of carbon fiber-reinforced bio-epoxy composites. The morphology of the composites was monitored by scanning electron microscopy (SEM), and the thermomechanical properties by [...] Read more.

The goal of this work was to investigate the effect of the biochar additive (2.5; 5; 10 wt.%) on the properties of carbon fiber-reinforced bio-epoxy composites. The morphology of the composites was monitored by scanning electron microscopy (SEM), and the thermomechanical properties by dynamic mechanical thermal analysis (DMTA). Additionally, mechanical properties such as impact strength, flexural strength andtensile strength, as well as the thermal stability and degradation kinetics of these composites were evaluated. It was found that the introduction of biochar into the epoxy matrix improved the mechanical and thermal properties of carbon fiber-reinforced composites. Full article

(This article belongs to the Special Issue Recent Advances in Fiber-Reinforced Epoxy Composites and Their Applications)

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30 pages, 412 KiB

Open AccessReview

Food Waste Composting and Microbial Community Structure Profiling

by Kishneth Palaniveloo, Muhammad Azri Amran, Nur Azeyanti Norhashim, Nuradilla Mohamad-Fauzi, Fang Peng-Hui, Low Hui-Wen, Yap Kai-Lin, Looi Jiale, Melissa Goh Chian-Yee, Lai Jing-Yi, Baskaran Gunasekaran and Shariza Abdul Razak

Processes 2020, 8(6), 723; https://doi.org/10.3390/pr8060723 - 22 Jun 2020

Cited by 131 | Viewed by 21643

Abstract

Over the last decade, food waste has been one of the major issues globally as it brings a negative impact on the environment and health. Rotting discharges methane, causing greenhouse effect and adverse health effects due to pathogenic microorganisms or toxic leachates that [...] Read more.

Over the last decade, food waste has been one of the major issues globally as it brings a negative impact on the environment and health. Rotting discharges methane, causing greenhouse effect and adverse health effects due to pathogenic microorganisms or toxic leachates that reach agricultural land and water system. As a solution, composting is implemented to manage and reduce food waste in line with global sustainable development goals (SDGs). This review compiles input on the types of organic composting, its characteristics, physico-chemical properties involved, role of microbes and tools available in determining the microbial community structure. Composting types: vermi-composting, windrow composting, aerated static pile composting and in-vessel composting are discussed. The diversity of microorganisms in each of the three stages in composting is highlighted and the techniques used to determine the microbial community structure during composting such as biochemical identification, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE), terminal restriction fragment length polymorphism (T-RFLP) and single strand-conformation polymorphism (SSCP), microarray analysis and next-generation sequencing (NGS) are discussed. Overall, a good compost, not only reduces waste issues, but also contributes substantially to the economic and social sectors of a nation. Full article

(This article belongs to the Special Issue Sustainable Development of Waste towards Green Growth)

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12 pages, 2511 KiB

Open AccessArticle

Elastic Constants Prediction of 3D Fiber-Reinforced Composites Using Multiscale Homogenization

by S. Z. H. Shah, Puteri S. M. Megat Yusoff, Saravanan Karuppanan and Zubair Sajid

Processes 2020, 8(6), 722; https://doi.org/10.3390/pr8060722 - 22 Jun 2020

Cited by 12 | Viewed by 3778

Abstract

This paper presents a multi-scale-homogenization based on a two-step methodology (micro-meso and meso-macro homogenization) to predict the elastic constants of 3D fiber-reinforced composites (FRC). At each level, the elastic constants were predicted through both analytical and numerical methods to ascertain the accuracy of [...] Read more.

This paper presents a multi-scale-homogenization based on a two-step methodology (micro-meso and meso-macro homogenization) to predict the elastic constants of 3D fiber-reinforced composites (FRC). At each level, the elastic constants were predicted through both analytical and numerical methods to ascertain the accuracy of predicted elastic constants. The predicted elastic constants were compared with experimental data. Both methods predicted the in-plane elastic constants “

E_{x}

” and “

E_{y}

” with good accuracy; however, the analytical method under predicts the shear modulus “

G_{x y}

”. The elastic constants predicted through a multiscale homogenization approach can be used to predict the behavior of 3D-FRC under different loading conditions at the macro-level. Full article

(This article belongs to the Special Issue Selected Paper from ICPER-2020 (7th International Conference on Production, Energy and Reliability))

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27 pages, 6060 KiB

Open AccessFeature PaperArticle

Phenol Degradation Kinetics by Free and Immobilized Pseudomonas putida BCRC 14365 in Batch and Continuous-Flow Bioreactors

by Yen-Hui Lin and Yu-Siang Cheng

Processes 2020, 8(6), 721; https://doi.org/10.3390/pr8060721 - 21 Jun 2020

Cited by 13 | Viewed by 3204

Abstract

Phenol degradation by Pseudomonas putida BCRC 14365 was investigated at 30 °C and a pH of 5.0–9.0 in the batch tests. Experimental results for both free and immobilized cells demonstrated that a maximum phenol degradation rate occurred at an initial pH of 7. [...] Read more.

Phenol degradation by Pseudomonas putida BCRC 14365 was investigated at 30 °C and a pH of 5.0–9.0 in the batch tests. Experimental results for both free and immobilized cells demonstrated that a maximum phenol degradation rate occurred at an initial pH of 7. The peak value of phenol degradation rates by the free and immobilized cells were 2.84 and 2.64 mg/L-h, respectively. Considering the culture at 20 °C, there was a lag period of approximately 44 h prior to the start of the phenol degradation for both free and immobilized cells. At the temperatures ranging from 25 to 40 °C, the immobilized cells had a higher rate of phenol degradation compared to the free cells. Moreover, the removal efficiencies of phenol degradation at the final stage were 59.3–92% and 87.5–92%, for the free and immobilized cells, respectively. The optimal temperature was 30 °C for free and immobilized cells. In the batch experiments with various initial phenol concentrations of 68.3–563.4 mg/L, the lag phase was practically negligible, and a logarithmic growth phase of a particular duration was observed from the beginning of the culture. The specific growth rate (μ) in the exponential growth phase was 0.085–0.192 h⁻¹ at various initial phenol concentrations between 68.3 and 563.4 mg/L. Comparing experimental data with the Haldane kinetics, the biokinetic parameters, namely, maximum specific growth rate (μ_max), the phenol half-saturation constant (K_s) and the phenol inhibition constant (K_I), were determined to equal 0.31 h⁻¹, 26.2 mg/L and 255.0 mg/L, respectively. The growth yield and decay coefficient of P. putida cells were 0.592 ± 4.995 × 10⁻³ mg cell/mg phenol and 5.70 × 10⁻² ± 1.122 × 10⁻³ day⁻¹, respectively. A completely mixed and continuous-flow bioreactor with immobilized cells was set up to conduct the verification of the kinetic model system. The removal efficiency for phenol in the continuous-flow bioreactor was approximately 97.7% at a steady-state condition. The experimental and simulated methodology used in this work can be applied, in the design of an immobilized cell process, by various industries for phenol-containing wastewater treatment. Full article

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17 pages, 1531 KiB

Open AccessArticle

Occurrence and Removal of Veterinary Antibiotics in Livestock Wastewater Treatment Plants, South Korea

by Jin-Pil Kim, Dal Rae Jin, Wonseok Lee, Minhee Chae and Junwon Park

Processes 2020, 8(6), 720; https://doi.org/10.3390/pr8060720 - 21 Jun 2020

Cited by 17 | Viewed by 3600

Abstract

In this study, livestock wastewater treatment plants in South Korea were monitored to determine the characteristics of influent and effluent wastewater, containing four types of veterinary antibiotics (sulfamethazine, sulfathiazole, chlortetracycline, oxytetracycline), and the removal efficiencies of different treatment processes. Chlortetracycline had the highest [...] Read more.

In this study, livestock wastewater treatment plants in South Korea were monitored to determine the characteristics of influent and effluent wastewater, containing four types of veterinary antibiotics (sulfamethazine, sulfathiazole, chlortetracycline, oxytetracycline), and the removal efficiencies of different treatment processes. Chlortetracycline had the highest average influent concentration (483.7 μg/L), followed by sulfamethazine (251.2 μg/L), sulfathiazole (230.8 μg/L) and oxytetracycline (25.7 μg/L), at five livestock wastewater treatment plants. Sulfathiazole had the highest average effluent concentration (28.2 μg/L), followed by sulfamethazine (20.8 μg/L) and chlortetracycline (11.5 μg/L), while no oxytetracycline was detected. For veterinary antibiotics in the wastewater, a removal efficiency of at least 90% was observed with five types of treatment processes, including a bio-ceramic sequencing batch reactor, liquid-phase flotation, membrane bioreactor, bioreactor plus ultrafiltration (BIOSUF) and bio best bacillus systems. Moreover, this study evaluated the removal efficiency via laboratory-scale experiments on the conventional contaminants, such as organic matter, nitrogen, phosphorus and veterinary antibiotics. This was done using the hydraulic retention time (HRT), under three temporal conditions (14 h, 18 h, 27 h), using the anaerobic–anoxic–oxic (A2O) process, in an attempt to assess the combined livestock wastewater treatment process where the livestock wastewater is treated until certain levels of water quality are achieved, and then the effluent is discharged to nearby sewage treatment plants for further treatment. The removal efficiencies of veterinary antibiotics, especially oxytetracycline and chlortetracycline, were 86.5–88.8% and 87.9–90.8%, respectively, exhibiting no significant differences under various HRT conditions. The removal efficiency of sulfamethazine was at least 20% higher at HRT = 27 h than at HRT = 14 h, indicating that sulfamethazine was efficiently removed in the A2O process with increased HRT. This study is expected to promote a comprehensive understanding of the behavior and removal of veterinary antibiotics in the livestock wastewater treatment plants of South Korea. Full article

(This article belongs to the Section Environmental and Green Processes)

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16 pages, 3949 KiB

Open AccessFeature PaperArticle

Mathematical Modeling of RNA Virus Sensing Pathways Reveals Paracrine Signaling as the Primary Factor Regulating Excessive Cytokine Production

by Jordan J. A. Weaver and Jason E. Shoemaker

Processes 2020, 8(6), 719; https://doi.org/10.3390/pr8060719 - 20 Jun 2020

Cited by 4 | Viewed by 3400

Abstract

RNA viruses, such as influenza and Severe Acute Respiratory Syndrome (SARS), invoke excessive immune responses; however, the kinetics that regulate inflammatory responses within infected cells remain unresolved. Here, we develop a mathematical model of the RNA virus sensing pathways, to determine the intracellular [...] Read more.

RNA viruses, such as influenza and Severe Acute Respiratory Syndrome (SARS), invoke excessive immune responses; however, the kinetics that regulate inflammatory responses within infected cells remain unresolved. Here, we develop a mathematical model of the RNA virus sensing pathways, to determine the intracellular events that primarily regulate interferon, an important protein for the activation and management of inflammation. Within the ordinary differential equation (ODE) model, we incorporate viral replication, cell death, interferon stimulated genes’ antagonistic effects on viral replication, and virus sensor protein (TLR and RIG-I) kinetics. The model is parameterized to influenza infection data using Markov chain Monte Carlo and then validated against infection data from an NS1 knockout strain of influenza, demonstrating that RIG-I antagonism significantly alters cytokine signaling trajectory. Global sensitivity analysis suggests that paracrine signaling is responsible for the majority of cytokine production, suggesting that rapid cytokine production may be best managed by influencing extracellular cytokine levels. As most of the model kinetics are host cell specific and not virus specific, the model presented provides an important step to modeling the intracellular immune dynamics of many RNA viruses, including the viruses responsible for SARS, Middle East Respiratory Syndrome (MERS), and Coronavirus Disease (COVID-19). Full article

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

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7 pages, 1043 KiB

Open AccessCommunication

Rapid and Enhanced Liquefaction of Pulp from Mango (Mangifera indica L.) cv. Totapuri Using Ultrasound-Assisted Enzyme Pretreatment

by Lebaka Veeranjaneya Reddy, Young-Min Kim and Young-Jung Wee

Processes 2020, 8(6), 718; https://doi.org/10.3390/pr8060718 - 20 Jun 2020

Cited by 6 | Viewed by 3572

Abstract

The effect of ultrasound and enzyme pretreatment (with pectinase, amylase, and cellulase) on the physicochemical properties (yield, viscosity, total soluble solids, and total phenolics) of mango juice was evaluated through a set of six experiments. Ultrasonication treatment alone showed no influence on juice [...] Read more.

The effect of ultrasound and enzyme pretreatment (with pectinase, amylase, and cellulase) on the physicochemical properties (yield, viscosity, total soluble solids, and total phenolics) of mango juice was evaluated through a set of six experiments. Ultrasonication treatment alone showed no influence on juice yield (54.6 ± 1.1%). However, the combined uses of ultrasonication with a pectinase or the enzyme mixture significantly increased the yield (94.1 ± 1.4% and 80.0 ± 2.1%, respectively) and decreased the enzyme pretreatment time (from 2 h to 1 h). Pectinase treatment assisted by ultrasonication was more effective with regard to juice yield, viscosity reduction, and the clarity of the juice than the enzyme mixture treatment with ultrasonication. Ultrasonication alone significantly increased the amount of total phenolics (65.5 ± 1.0 mg/100 mL) and showed a slight reduction of viscosity and improvement of clarity compared to the control. Full article

(This article belongs to the Special Issue Biocatalysis, Enzyme and Process Engineering)

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24 pages, 1338 KiB

Open AccessArticle

Supplier Selection for the Adoption of Green Innovation in Sustainable Supply Chain Management Practices: A Case of the Chinese Textile Manufacturing Industry

by Yun Yang and Ying Wang

Processes 2020, 8(6), 717; https://doi.org/10.3390/pr8060717 - 20 Jun 2020

Cited by 31 | Viewed by 5430

Abstract

Globally, increasing environmental issues are gaining attention to facilitate the adoption of green innovation for sustainable supply chain management (SSCM). Sustainable environmental practices have been well-considered in the literature; however, no study has focused on adopting green innovation practices for sustainable development. Thus, [...] Read more.

Globally, increasing environmental issues are gaining attention to facilitate the adoption of green innovation for sustainable supply chain management (SSCM). Sustainable environmental practices have been well-considered in the literature; however, no study has focused on adopting green innovation practices for sustainable development. Thus, environmental management authorities are putting pressure on industries to implement green innovation criteria for SSCM operations. Moreover, it is important to select traditional suppliers to transform its practices to that of sustainable supply chains in order to achieve the industry’s sustainable supply chain goals. In response, this research identified and analyzed the green innovation criteria for SSCM and then selected a supplier that could implement green aspects in the SSCM. This study developed an integrated multi-criteria decision making (MCDM) model using the fuzzy analytical hierarchy process (FAHP) and the fuzzy technique for order of preference by similarity to ideal solution (FTOPSIS). The objective of this study was to analyze suppliers to implement green innovation criteria for SSCM practices in the textile manufacturing companies of China. This study reviewed and identified three green innovation criteria and seventeen sub-criteria. Then, the FAHP technique was employed to analyze and rank green innovation criteria and sub-criteria. Finally, the FTOPSIS method was used to investigate and rank eight suppliers. The findings of the FAHP indicated that economic (EC) criteria were the most vital green innovation criteria in the SSCM. Furthermore, the FTOPSIS results revealed that supplier 5 was the most suitable supplier for implementing green innovation criteria in the SSCM. These findings will help managers, practitioners, and policymakers implement green innovation criteria in sustainable manufacturing supply chains. Full article

(This article belongs to the Special Issue Advances in Sustainable Supply Chains)

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