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This study proposes a method to determine the two‐dimensional absorption capacity of paper towels. Individual plies were tested to minimize the effects of transverse wicking on wetting. The method involves arbitrary point source injection of liquid into the towel surface while recording microscopic images of the wetted areas. The samples were selected from the main manufacturing processes: conventional wet pressing and through‐air drying. Wetting graphs that illustrate the dynamic and static wetting behaviors were generated. The driving force was found to have a negligible effect on the maximum wetted area. The maximum wetted area and the paper grammage were used to determine the two‐dimensional absorption capacity. The results were validated by the basket‐immersion test method. [ABSTRACT FROM AUTHOR]

The present work investigates the energy performance analysis of a heptad‐based multiple‐stage evaporator (MSE) under steady and transient conditions, integrated with different energy reduction schemes (such as steam split, feed split, and feed preheater). The steady‐state analysis was performed to optimize the steam economy subjected to the developed steady‐state energy models as the equality constraints. The simulated optimization is a maximization problem and is solved by Interior‐Point Optimizer and Gray Wolf Optimizer on two different platforms, GAMS and MATLAB, respectively. Further, transient and stability analyses were performed by developing and representing the nonlinear dynamic energy models to the state‐space representation using linearization. [ABSTRACT FROM AUTHOR]

A comparative study of chemical looping combustion (CLC) with paper, plastic, and coal as fuel was carried out. Experiments were performed in a laboratory fluidized‐bed reactor by alternating between reduction and oxidation cycles. The results obtained indicated that a higher temperature leads to an increase in the CO2 yield and carbon conversion for all fuels. Paper had the highest fractional conversion of CO to CO2 followed by polyvinyl chloride (PVC) and coal. This was due to the higher fraction of volatiles in paper compared to PVC and coal. Scanning electron microscopy (SEM) analysis of the oxygen carrier particle after each of the solid fuel experiment was carried out. For the used ilmenite, there was a slight difference in the morphology for the three different fuels. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction was applied to treat paper‐plastic‐aluminum (Al‐PE‐Pa) complex packaging waste for bio‐oil production. The interactive effects between the main components of paper fiber, low‐density polyethylene (LDPE), and aluminum foil in such complex material were studied. The co‐liquefaction of paper fiber and LDPE had a significant synergistic effect. The addition of hydrogen‐rich LDPE effectively promoted the removal of oxygen‐containing groups. Aluminum foil had only a slight impact on the liquefaction of paper fiber, but it can significantly decrease the oxygen content of the bio‐oil, increase the high heating value of the bio‐oil, and significantly reduce the ester and phenol contents in the bio‐oil. The co‐liquefaction of paper fiber/LPDE/aluminum foil exhibited superimposed effects of paper‐plastic synergy and in‐situ hydrogenation of Al‐H2O reaction. A new pathway for the energy utilization of Al‐PE‐Pa complex packaging waste is provided. [ABSTRACT FROM AUTHOR]

De‐inking sludge, an ash‐rich recycling paper solid waste, is generated in huge amounts. The catalytic deoxygenation potential of calcium‐based de‐inking sludge in co‐pyrolysis mode with wood and its neat thermal conversion to sustainable biofuels are investigated. Wood, de‐inking sludge, and their blends are processed in a thermocatalytic reforming (TCR) system. In the presence of de‐inking sludge, the oxygen content in the organic phase decreases and the bio‐oil calorific value improves as compared to the neat wood‐derived bio‐oil. The TCR processing of neat de‐inking sludge produces a bio‐oil with low oxygen content and higher calorific value. [ABSTRACT FROM AUTHOR]

Energy consumption optimization belongs to the main agendas in sustainable industries. Here, cost‐saving opportunities in the pulp and paper industry as one of the largest industrial energy consumers worldwide are in the focus. Energy‐saving measures are proposed employing a large‐scale mathematical model of a paper machine based on mass and energy balances supported by real‐time experiments in paper machine operation. The presented measures are based on the optimization of paper stock pumping and a drying section operation. The total energy‐saving effect of the four proposed measures accounted for a reduction in specific heat and electricity consumption by more than 2 %. The proposed procedures require no or low investment costs with the overall simple rate of return of less than one year. [ABSTRACT FROM AUTHOR]

Electroosmotic flow (EOF) in a fractal tree‐like microfluidic network has wide applications. To reduce the fluid resistance of EOF in the network, this paper numerically studies the influences of the branch convergence α, the level convergence κ, the length ratio λ, the branching number N, the maximum branching level M, and the channel height H of a fractal tree‐like convergent microchannel network (FTCMCN) on the EOF flowrate and analyzes the optimal structure of FTCMCN to maximize the EOF transport efficiency. The present paper finds the optimal structure of FTCMCN and its dependence on the various geometric and structural parameters. This work is beneficial to the optimization design of the FTCMCN to achieve the highest EOF transport efficiency. [ABSTRACT FROM AUTHOR]

Quality‐related fault detection has become a hot research topic in recent years. It is not reliable to measure quality‐related relationships only by mutual information among process variables and single‐quality variables. Frequent alarms for quality‐unrelated faults seriously affect the normal operation of industrial production. At the same time, the strong nonlinearity of the process data leads to the difficulty of feature extraction. In this paper, we propose a fault detection algorithm based on nonlinear quality‐related neighborhood embedding neural orthogonal mapping (QR‐NENOM). First, quality‐related and quality‐unrelated variables are selected by Bayesian fusion mutual information, and the weighted method of mutual information is used to enhance the quality‐related information and suppress the quality‐unrelated information. Second, local manifold information is obtained by reconstructing nearest neighbors of process data, and key features are extracted by the nonlinear method composed of neural network and orthogonal mapping. Then, statistical indicators are established to complete fault detection. Finally, the nonlinear feature extraction ability of NENOM is verified by numerical examples, and the QR‐NENOM algorithm proposed in this paper is applied to the penicillin fermentation process. Comparative experiments show that QR‐NENOM has better detection performance for quality‐related faults and fewer alarms for quality‐unrelated faults. [ABSTRACT FROM AUTHOR]

In this paper, the seeded batch cooling crystallization of sodium phosphite (SP) is simulated and optimized through a coupled method of the genetic algorithm and nonlinear programming. At first, the modeling and simulation test methods of the crystallization process are applied for the crystallization of SP, which expands the relevant study of SP from the experiment to the simulation. A comprehensive model is established in MATLAB/Simulink, and based on this model, the results of the common cooling strategy (linear cooling) on the process are investigated. Meanwhile, the process sensitivity to the change of seeding conditions is analyzed. Then, the coupled optimization method based on the genetic algorithm and nonlinear programming is applied to optimize the crystallization process for the first time, and the obtained optimized cooling strategy is compared to the result of the traditional nonlinear programming method (NLPM). The traditional NLPM has more significant effects on large seeding mass and small mean size, while the coupled method has better adaptability. When the coefficient of variation is almost fixed, the cooling strategy obtained by the coupled method could produce more crystals with large mean size. In addition, the end of the process can be reached earlier. The results show that the coupled method is more suitable for the optimization of the batch cooling crystallization of SP. [ABSTRACT FROM AUTHOR]

Converting the abundant biomass resources in nature into fine chemicals can not only reduce carbon emissions but also effectively deal with the depletion of fossil energy, which is of strategic significance for sustainable development. In this paper, by optimizing the content of bimetallic components, highly active co‐doped Co1Cu3 bimetallic silicate was designed and synthesized. After reduction, a highly dispersed and stable Co1Cu3/SiO2 catalyst was obtained, which was used to catalyze the aqueous phase hydrogenation of furfural (FFR) to cyclopentanone (CPO). Compared with the traditional supported catalyst, the Co1Cu3/SiO2‐ammonia evaporation (AE)‐300 catalyst prepared by AE has the best performance. Under the optimal reaction conditions, the conversion of FFR was as high as 95.1 % and the selectivity of CPO was 88.6 %. This high activity can be attributed to the formation of highly dispersed and uniform metal active sites with low content of Co. At the same time, the formation of flocculent silicate enhances the synergism between CoCu and SiO2 support and increases the specific surface area of the catalyst. In addition, the experimental results show that the reaction carbon balance will be destroyed with the high concentration of FFR solution. [ABSTRACT FROM AUTHOR]

Accurate prediction of nitrogen oxide (NOx) emission is crucial for effectively controlling pollution in municipal solid waste incineration processes. However, it is challenging to construct a NOx emission prediction model with high prediction accuracy and easy engineering application. To address this, this paper proposes a robust and easily applicable NOx emission trend prediction model oriented to engineering applications, utilizing the partial least squares (PLS) method with the time series reconstruction and exponential weighting (TS‐EW‐PLS). The model is verified using operational data from an actual waste incineration process, and comparative analysis with the PLS model showed that the TS‐EW‐PLS model achieved a remarkable improvement of 27–38 % in prediction performance. [ABSTRACT FROM AUTHOR]

Fresh water consumption and wastewater management is a mandatory task to conserve water resources and to reduce wastewater discharge from chemical production processes. Such objectives have been addressed in many industrial sectors which consume large amounts of fresh water. Possibilities for reducing wastewater volumes by regeneration and recycling routes in the pulp and paper industry are analyzed. During pulp preparation and paper making processes by the Kraft pulping method a large amount of water is required to deliver the finished paper product. Reverse osmosis (RO) is applied for the analyses as an interception separation technology to reduce salt concentrations in wastewater streams for recycling purposes. The RO network synthesis problem is formulated as mixed integer nonlinear programming model which is solved using the general algebraic modeling system. A preliminary cost estimate indicates economic incentives by installation of RO units to avoid wastewater discharge and generate relatively clean water streams for inter-plant usage. [ABSTRACT FROM AUTHOR]

The anaerobic batch digestion of freeze‐dried and ground (< 1.5 mm) maize silage, wheat straw, cattle manure, pig manure, and cellulose filter paper was investigated with substrates placed in polyester filter bags. Gas production dynamics of bagged and non‐bagged substrates were compared. By using batch bottles running in parallel with those used for gas measurement, substrates could be sampled over time and various parameters measured for both substrate and bulk liquid. The bags allowed an immediate mass loss into the bulk liquid with some substrates and a generally lower rate of gas production. This method requires refinement but has potential for the study of the dynamics of substrate degradation during anaerobic digestion. [ABSTRACT FROM AUTHOR]

Predicting the productivity of the freeze desalination process is of key importance. This paper describes an analytical method to predict the productivity for the progressive freeze desalination process utilizing the rectangular channel crystallizer design. The mass of ice produced during the process is considered a measure of productivity. The model was developed using heat and mass transfer modeling. The effect of coolant temperature (from −8 to −16 °C), liquid flow rate (4400–6000 mL min−1), and initial salt concentration of the liquid (1.5–7 wt%) on the mass of ice produced was investigated. The analytical results of the mass of ice produced were compared with the experimental data. A plausible match was found between the analytical and experimental results, with an error range between 6 % and 9 %. The model can predict the mass of ice produced for given values of the initial salt concentration of the liquid, initial mass of the liquid, salt concentration of thawed ice, liquid flow rate, and coolant temperature. [ABSTRACT FROM AUTHOR]

This review presents the technical and operational performances of solar and biomass energy technologies viz photovoltaic thermal (PVT) and biomass gasification systems. This work aims to offer a reference and guidelines to the renewable energy‐related players, especially for those at the operational level and investors. This paper highlights the technical advantage of hybrid PVT with phase change material in terms of electrical and thermal efficiencies. While the operational performance of biomass gasification is thoroughly discussed via sensitivity analysis, the potential integration between solar and biomass gasification technologies is explored to complement and bolster the capabilities of both renewable systems within the power energy mix portfolio. Finally, few directions and significant takeaways considering the technical criteria are addressed for identifying efficient renewable energy generation. [ABSTRACT FROM AUTHOR]

In this paper, granular flow is studied using particle image velocimetry (PIV) in two different geometries, that is, rectangular box and cylindrical bladed mixer. Effects of parameters like blade rake angle, bed height, moisture content, and the number of blades were studied. The shear rate and velocity magnitude of granular bed were calculated using PIV. The presence of moisture in the granular bed added additional cohesive forces and reduced shear rate between different layers of particles. Shear rate and shear forces were maximal at the tip of the blade. Temperature variations in the granular bed were measured experimentally and results were compared for static and mixing beds. [ABSTRACT FROM AUTHOR]

Trends towards product differentiation, fast changing market conditions, and shorter product lifecycles demand flexible production solutions for the chemical industry. Modular production systems promise to provide the required capacities as needed in a short period of time. However, the potential of modular production systems can only be fully utilized if they are embedded in modular and thus flexible logistics processes. For this reason, standardized logistic modules need to be defined. Process standardization is the starting point for reducing the number of variants and minimizing the number modules. Thus, in this paper a reference process model is developed. The standardized processes defined in this model are then used to form modules by applying a method from cluster analysis. [ABSTRACT FROM AUTHOR]

Particle suspension is considered powerful and perspective in enhancing heat transfer, but the unclear nature of particle‐loaded flow limits further understanding of particle suspension. Therefore, in this paper, orthogonal experiments and the arbitrary Lagrangian‐Eulerian method were used to investigate the heat transfer characteristics of particle‐loaded flow. Results indicate that when the particle is at the inlet of the microchannel, the factors arranged in important order are the Reynolds number, blockage ratio, particle initial position, specific heat capacity, and thermal conductivity. When the particle is far from the microchannel inlet, the factors arranged in important order are the Reynolds number, blockage ratio, particle initial position, thermal conductivity, and specific heat capacity. [ABSTRACT FROM AUTHOR]

In space exploration activities, a large amount of materials needs to be carried, which limits the sustainable development of exploration activities. In‐situ resource utilization (ISRU) is an important means to realize resource recycling and continuous space exploration, which converts space resources into oxygen and hydrocarbon fuels. The traditional ISRU in outer space mainly uses high temperature and high pressure to electrolyze water or reduce CO2, having problems such as low conversion efficiency, high energy consumption, and excessive equipment volume. Here, an electrochemical catalytic synthesis technology based on a microfluidic device is proposed, which can convert H2O and CO2 into O2 and organic matter by electrocatalytic method at room temperature and achieve efficient energy and matter conversion. The gas‐liquid mixing and electrochemical reaction were analyzed. A mathematical model of gas‐liquid two‐phase mixing and microfluidic chemical reaction was established. The research results demonstrate the reliability and efficiency of the microfluidic reaction device designed in this paper for ISRU. [ABSTRACT FROM AUTHOR]

Withdrawal: The withdrawal has been agreed following concerns regarding manipulation of the peer review and publishing process. Concerns were originally raised by third parties [1, 2]. Further investigation by the publisher has found manipulation of the peer review process. The withdrawal has been agreed because the peer review of the article was compromised. [1] B. E. Perron, O. T. Hiltz‐Perron, B. G. Victor, Revealed the inner workings of a papermill, 2021. https://retractionwatch.com/2021/12/20/revealed‐the‐inner‐workings‐of‐a‐paper‐mill/ [2] A. Abalkina, Publication and collaboration anomalies in academic papers originating from a paper mill: evidence from a Russia‐based paper mill, 2022. https://arxiv.org/abs/2112.13322 The above article, published online as accepted article, prior to the version of record, on June 07, 2021 in Wiley Online Library (http://wileyonlinelibrary.com) has been withdrawn by agreement between the journal's Editor in Chief and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Electrochemical performance of cathode active materials (CAMs) is dependent on the properties of coprecipitated precursors (pCAMs). This is a sensitive process affected by several reaction parameters such as temperature, pH, concentration of reactants, agitation rate, and residence time. In this paper, the effect of parameters influencing the particle size growth and the physical properties, such as particle morphology and tapped density, was studied in the coprecipitation of Ni(OH)2. Formation of a homogeneous population with narrow particle size distribution was observed, followed by a more heterogeneous population of dense particles. Ammonia concentration and residence time had significant effects on particle size growth and morphology, but agitation rate also had an impact. [ABSTRACT FROM AUTHOR]

This paper presents a numerical modeling approach for investigating crescent‐type internal gear pumps (CIGPs) considering radial micromotions of both gears. The modeling approach couples a lumped parameter pressure solver on the bulk fluid domain, with a transient computational fluid dynamics film simulator based on transient gap geometries solved from the gear loading forces. Simulation results on a commercial unit shows that for a wide range of operating conditions, the model gives volumetric efficiency predictions with errors less than 2 % comparing to measurements. To highlight the importance of considering radial micromotions, the paper also provides the results achieved assuming nominal position for both gears. [ABSTRACT FROM AUTHOR]

Volatilities in market demand and resource supply require flexible production and logistic concepts in the chemical industry. Modular production plants provide an answer that also promises advantages for operation in decentralized production networks. However, intralogistic processes also have to cope with volatile requirements from the supply chain, such as fluctuating demand quantities, products or packaging types. Therefore, this paper focuses on production‐related intralogistic processes and develops modular intralogistic concepts for flexible operation in the chemical industry. On this basis, a framework for the flexible operation of intralogistic systems is derived, in which organizational and legal developments are considered in addition to technological solutions. [ABSTRACT FROM AUTHOR]

Due to the density differences between gases and liquids, the gas supply often limits the conversion of gas‐liquid reactions in slug flows. This paper investigates the permeation of reacting gas into an existing gas‐liquid slug flow in fluorinated ethylene propylene capillaries of up to 40 m in length, representing a significant sizing‐up of tube‐in‐tube reactors (maximum 4 m). The amount of gas introduced can be estimated with permeation coefficients given in the literature. Moreover, existing gas bubbles serve as reservoirs for the permeating gas, maintaining the advantageous slug flow pattern. [ABSTRACT FROM AUTHOR]

Different promoters have a significant impact on the catalyst performance. In this paper, the effects of different promoters on the physical properties and catalytic behavior of methane dry reforming catalysts were investigated. A series of characterizations showed that the Mg, Ba, and Ca promoters increased the basicity of the catalysts. However, their high concentration of OH− leads to the destruction of Ni3Si2O5(OH)4 species, which results in a decrease of catalytic performance. The addition of Ce significantly improves the catalyst stability. After 100 h of Ni‐5Ce‐MSC reaction, there was almost no carbon deposition, exhibiting high activity and resistance to carbon accumulation. These findings provide a new perspective for the design of nickel‐based dry reforming catalysts. [ABSTRACT FROM AUTHOR]

The capture of CO2 from air via direct air capture (DAC) is a promising way to reduce the carbon dioxide concentration in the atmosphere. The carbonation of calcium‐based adsorbents using ambient conditions is particularly interesting for DAC due to its high theoretical CO2 uptake capacity and its low cost. In this paper, a new preparation method of synthetic calcium oxide‐based pellets for a DAC process was investigated. Their CO2 capture performance was studied experimentally in a fixed‐bed column and characterization was performed via Brunauer‐Emmett‐Teller (BET) analysis, mercury porosimetry, X‐ray diffraction, and scanning electron microscopy. Higher heating rates during the precursor calcination process and higher relative humidities during the carbonation process were found to lead to higher CO2 capture efficiencies. All prepared pellets showed good mechanical stability. [ABSTRACT FROM AUTHOR]

The Iranian transportation industry is an energy‐intensive sector with a wide variety of destructive environmental effects. The use of hydrogen is a promising method to reduce CO2 emissions. Methane decomposition is one of the reliable processes to yield hydrogen. In this paper, the levelized cost, technical parameters, and CO2 emissions of each hydrogen production method are determined and discussed. Finally, it is concluded that steam methane reforming is almost a clean and efficient method of hydrogen production. Besides, maximum generated hydrogen values were obtained using the electrolysis process. To be more precise, in this process, the levelized cost of hydrogen production by photovoltaic, wind, and gas‐combined cycle were evaluated. [ABSTRACT FROM AUTHOR]

In pneumatic automation, downstream throttled pneumatic drives are widely used to perform motion tasks because of their low cost, robustness, and high power density. However, this drive technology is generally regarded as having a large energy saving potential. Hence, multiple researchers have proposed control strategies aiming to improve the efficiency of systems using pneumatic drives. However, most of those developments increase the system complexity and commissioning efforts, which hinders a broad application. This paper presents alternatively a simple to implement energy‐saving measure, which relies on a novel energy‐saving speed controller. Furthermore, a design method for the controller is proposed and subsequently analyzed using a lumped parameter model. [ABSTRACT FROM AUTHOR]

The optimization of lubricated sealing systems with respect to the stick‐slip effect requires a friction model that describes the complex friction behavior in the lubricated contact area. This paper presents an efficient dynamic friction model based on the Stribeck curve, which allows to investigate the influencing parameters through finite element (FE) simulations. The simulation of a tribometer test using this friction model proofs that the model correlates well with the tribometer test results. It is shown that the system stiffness has a significant influence on the stick‐slip tendency of the system. [ABSTRACT FROM AUTHOR]

Plant antibiotics in water are considered an emerging issue due to their interference with human health. Antibiotics protect crops from diseases; however, low levels of antibiotics are found in wastewater due to their incomplete removal. Several treatment methods are available, but with limitations such as high operation and maintenance costs and the formation of toxic by‐products. Antibiotic removal by adsorption is an alternative method, being a low‐energy process with simple operation, mainly if used with carbonaceous adsorbents. Antibiotic removal was fit to a wide variety of isotherm and kinetic models, with the Freundlich isotherm as the most employed one. This paper aims to review the use of the adsorption process in the removal of plant antibiotics from water systems. [ABSTRACT FROM AUTHOR]

Liquid foams occur whether intentionally or unintentionally across different industrial sectors. The detection of foam and characterization of liquid content currently requires complex measurement methods such as electrical conductivity measurements. This paper presents a novel method for foam detection and characterization of its liquid fraction based on a capacitive level sensor. A correlation between the sensor output signal and defined liquid fractions of dry to wet foam indicated a high accuracy of this sensor technique. Regarding the sensor operation in different liquid solutions, a minimum screw‐in depth is presented. The sensor allows minimal invasive inline measurements in equipment regardless of the wall material and of extreme process conditions, e.g., explosion hazard areas. [ABSTRACT FROM AUTHOR]

Efficient mixing conditions for similar fluids in T‐Jets mixers are well‐established. This paper extends the characterization of the mixing of dissimilar fluids. Planar laser‐induced fluorescence images were captured using fluids with a viscosity ratio between 1.2 and 3. Flow visualizations showed that the best mixing conditions are achieved when the jets are well‐balanced, and the onset of a chaotic flow regime is determined by the Reynolds number of the more viscous fluid (ReHjet > 100). Computational fluid dynamics simulations were also performed to get deeper insight into the flow field and mixing dynamics, enabling the prediction of the impingement point position. An analytical model based on jets' kinetic energy rate balance is proposed as a design tool to predict the impingement point position. [ABSTRACT FROM AUTHOR]

It is essential to understand the interaction energy between water and ionic liquids (ILs) in search of ILs for dehumidification applications. In this paper, the intermolecular interaction energy between water and 1‐ethyl‐3‐methylimidazolium ([EMIM])‐based ILs was investigated. The vapor‐liquid equilibrium data were first measured for solutions of [EMIM][BF4], [EMIM][N(CN)2], [EMIM][CF3SO3], and [EMIM][CH3SO3] with water molar fractions of 8–95 % at temperatures of 303–343 K. The IL‐IL and water‐IL intermolecular interaction energies were determined by using the correlated non‐random two‐liquid model. The results revealed that fluorine atoms in anions reduce the attraction energy between IL and water, and thus, decrease the water affinity. [ABSTRACT FROM AUTHOR]

Heat recovery and promotion is essential to decarbonization, and chemical heat pumps based on reversible organic reactions can aid to fulfil this. This paper studied the isopropanol/acetone/hydrogen (IAH) and the tert‐butanol/isobutene/water (tB/iB) systems regarding their performance and economic competitiveness through simulation and found that the IAH presents satisfactory performance and has the potential to be a very promising solution in increasing the overall energy efficiency while also preventing the emission of massive amounts of CO2 and other greenhouse gases released during energy production and transformation. This system presents enough arguments to become a very successful solution if proper politico‐economic support and incentives are established and put into practice. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the integration of corn in existent sugarcane mills in Brazil to increase ethanol production. The study considered an autonomous distillery factory of medium‐capacity, and the incremental benefits from corn processing during the sugarcane off‐season. A process simulation and a cost analysis were developed to estimate the technoeconomic feasibility. The data and parameters employed were in accordance with Brazilian practice. The results show that a sugarcane plant operating 4 months during the off‐season with corn requires an investment of US$ 13.4 million, obtained the return of investment in 4 years, and a revenue estimated in US$ 666K yr−1 due to ethanol surplus production. [ABSTRACT FROM AUTHOR]

In early project stages, often no simulation results are available for dividing‐wall columns. Hence, shortcut methods are used to estimate suitable vapor and liquid splits. In a previous paper, it was demonstrated that V·min diagrams are a suited tool to satisfy this need. However, it has turned out that it shows weaknesses for columns with finite or non‐optimal stages. This contribution closes that gap and presents an extended approach to derive suited initial guesses. For this purpose, the original V·min diagram is combined with a heuristic approach to calculate Pareto‐optimal column designs resulting in a stage‐adapted V·min diagram. A comparative study illustrates that the new approach is a powerful tool to generate reliable guesses for multiple dividing‐wall column simulations with finite stage numbers. [ABSTRACT FROM AUTHOR]

Graphite paper is introduced as efficient and low-cost anode in an air-cathode microbial fuel cell (MFC) for simultaneous wastewater treatment and power generation using real food wastewater. Graphite paper as the cheapest investigated material provided the best electrochemical results in an MFC with an excellent open cell voltage. The significantly increased power generation could be attributed to the large surface area of the anode, leading to enhanced bacterial attachment on the graphite anode surface. Regarding wastewater treatment, the graphite anode exhibited the highest removal of organic pollutants and the highest coulombic efficiency. It shows an excellent efficiency as a bio-anode in the air-MFC for producing electricity and treating industrial wastewaters without requiring external mediators. [ABSTRACT FROM AUTHOR]

A microchannel heat exchanger with a triangular wave and symmetrical triangular wave structure was proposed in this paper. In addition, a new N‐type microchannel heat exchanger was developed to balance the heat transfer performance and pressure drop. The relationship between different configurations of the N structure of the microchannel and the heat transfer performance was analyzed. The results showed that, at a high inlet flow rate, the symmetrical triangular wave microchannel had the best heat transfer performance, followed by the triangular wave microchannel and the straight channel. At the same flow rate, the degree of disturbance of the fluid was highest in the symmetrical N‐structure microchannel, and an excellent heat transfer effect was observed. [ABSTRACT FROM AUTHOR]

Aspen Plus has become one of the most common process simulation tools for both academia and industrial applications. In the last decade, the number of the papers on Aspen Plus modeling of biomass gasification has significantly increased. This review focuses on recent developments and studies on modeling biomass gasification in Aspen Plus including key aspects such as tar formation and model validation. Accordingly, challenges in modeling due to specific assumptions and limitations will be highlighted to provide a useful basis for researchers and end‐users for further process modeling of biomass gasification in Aspen Plus. [ABSTRACT FROM AUTHOR]

Particle formulation processes such as continuous fluidized‐bed layering granulation (FBLG) are widely applied in chemical, food, and pharmaceutical industries. Particle size and particle porosity are important product properties in FBLG. In this paper, a new concept is presented for the simultaneous control of both properties. The new concept allows stable process operation, automatic adjustment of the desired product properties, and rejection of unforseen disturbances. [ABSTRACT FROM AUTHOR]

Waste organic biomass is regarded as the most suitable renewable source for conversion to produce biofuels and biochemicals. Owing to its high‐energy potential and abundancy, lignocellulosic biomass can be utilized to produce alternative energy in the form of gaseous and liquid biofuels. Microbial conversion of waste biomass is the most successful technology for the generation of biohydrogen through dark fermentation. Different biological hydrogen production technologies along with process parameters are described in this review paper with the focus on dark fermentation. The production of biohydrogen from various substrates is summarized along with the integrated mode of dark fermentation and photofermentation. Hydrogen generation through biological water‐gas shift reaction is also highlighted. [ABSTRACT FROM AUTHOR]

Product design and engineering (PDE), originally heralded as a new paradigm of chemical engineering, aims to define new and/or improved products based on customer needs and/or new technologies. A comprehensive discussion of PDE as a building block for chemical engineering education, research, and practice is still lacking, preventing a broader impact on academic and industry realities more and more concerned with the "knowledge economy". The purpose of the present paper was to contribute to the mitigation of this gap by presenting the results of the EFCE Section Group PDE survey based on PDE academia and industry expert and practitioner feedback as well as on a literature review. Status and challenges of PDE are discussed and academic and industry perspectives are mapped. [ABSTRACT FROM AUTHOR]

The typically undesired release of particles from bulk materials can occur in a wide range of material‐handling processes and thus present a hazard to humans and the environment. Therefore, the dust formation tendency is an important material property and depends on the specific type of stress. A forecast of the dust formation tendency could simplify and expedite the assessment of possible hazard potentials as it would eliminate the need for comprehensive testing. For this paper, the UNC dustiness tester was applied to analyze the dust formation tendency of nine different materials. Based on the results obtained and taking account of the measurement method, it was possible to develop an apparatus‐specific forecast parameter, which allowed the derivation of empirical forecast formulas for the UNC dustiness tester. Undesired release of particles from bulk materials occurring in material‐handling processes can present a hazard to humans and the environment. Dust formation tendency as an important material property depends on the specific type of stress. A semi‐empirical forecast parameter was derived based on experimental analyses with a UNC dustiness tester and used to develop forecast formulas. [ABSTRACT FROM AUTHOR]

To keep biogas production competitive against alternatives in the energy sector, operating costs of biogas plants must be reduced. Up to 50 % of the energy consumption in biogas plants is contributed by mixing of biomass slurry. Thus, optimization of the mixing system is a promising approach to increase the overall efficiency of biogas plants. Investigations to find the optimal conditions of mixing are challenging in full‐scale biogas digesters. Two main strategies to study biomass mixing in laboratories are to build a scale‐down digester using an artificial substrate to mimic biomass, and to develop a computational fluid dynamics (CFD) model to simulate the mixing process. In this paper, a combined approach is carried out: a CFD model is presented and verified experimentally. Mixing of biomass in biogas plants requires high energy input. A comprehensive computational fluid dynamics method to assess the mixing quality in biogas digesters is described and validated. Conclusions about positioning and working methodology of the mixers are indicated and can constitute the basis of rules and guidelines for the design and optimization of biomass mixing systems. [ABSTRACT FROM AUTHOR]

The increasing number of fluctuating renewable power producers in the electricity grid leads to several challenges in the grid's infrastructure and its operation. Biomass combustion plants, however, can be modified to increase the flexibility of power production by integrating steam storage devices. In this paper, the available storage systems are evaluated, considering the boundaries of the plants and the requirements of power grids and markets. An objective result is generated by conducting a Delphi study using energy experts. The utility‐value‐analysis method is used to identify the most promising storage concept. Using this methodology, the resulting storage concept is found to be a combination of a steam accumulator and a solid storage. Several steam storage systems to achieve a controllable power generation from biomass combustion plants are available. These systems are evaluated according to the boundaries of the plants as well as the electricity grid and market demands. An adapted analytic hierarchy process with implementation of the Delphi survey was performed to identify the most suiting storage device. [ABSTRACT FROM AUTHOR]

Abstract: Continuous research and development of reverse osmosis (RO) technologies has led to the production of membranes that are very effective with high salt rejection abilities. As temperature is one of the factors that affects salt rejection capabilities in membranes, this paper investigates the effect of temperature on the thickness of the concentration polarization layer (CPL) deposited on thin‐film composite seawater RO membranes. Two types of membranes were studied: those with ex situ macromolecules and those with in situ macromolecules. FilmTec's reverse osmosis system analysis design software was used to predict the variation of salt rejection and permeate flow rate with temperature. The impact of these variations on the thickness of the CPL was analyzed for different polyamide concentrations in the membrane. [ABSTRACT FROM AUTHOR]

Silica removal is the main bottleneck for a high reuse of deinking paper mill effluents due to silica scaling on the reverse-osmosis units generally used. The efficiency of inorganic-organic hybrid coagulants formed by the combination of polyaluminum nitrate sulfate (PANS) with different dosages of cationic polyacrylamide (PAM) or polyamines (PA) on silica removal is analyzed. These hybrids significantly increased the silica and chemical oxygen demand (COD) removal at all pH values studied, with PA modification being the most efficient. While conventional aluminum coagulants allow high silica removal, only at both high pH and dosages the PA derivatives achieve high silica and soluble COD removal without pH adjustment. PAM hybrids only slightly improved the efficiency of PANS at the highest active contents. [ABSTRACT FROM AUTHOR]

Coagulation is presented as an efficient alternative to reduce the silica content in effluents from recovered-paper mills that are intended to be recycled by a final reverse-osmosis (RO) step. Coagulation pretreatment by several polyaluminum chlorides (PACls) or FeCl3 was optimized prior to the RO process. PACls with low alumina content and high basicity achieved almost a 100 % removal of silica at pH 10.5. A good reduction of the silica content was attained without regulating the pH by adding one of these PACls. Silica removal was related to the structure of the produced clots in which cylindrical particles produced higher silica removal. All coagulants removed more than 50 % of the chemical oxygen demand (COD). [ABSTRACT FROM AUTHOR]

Abstract: Commercial low‐cost sensors for particulate matter measurements are a fast growing market and find many applications in the particulate matter (PM) immission characterization in the environment. This application includes uncontrolled factors such as humidity, making the devices more prone to errors. These factors are controllable in closed emission control applications, turning these affordable sensors into potential monitoring devices for exhaust concentrations. Time‐resolved PM emissions of a surface filter were measured at various concentration levels. The suitability and limitations of a SDS011 PM2.5 low‐cost sensor were evaluated by comparing its PM readings to a welas® 2100 sensor by Palas®. Experimental setup and results are presented and further discussed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: An overview is given over different types of gas storages and their pressure/level relationship, which is crucial for the design of the plant's gas system. It focuses on the design of air‐inflated double‐membrane gas storages, their blowers, and pressure control valves. During the design phase of a biogas plant, the responsible engineer must calculate the pressure gradient for several scenarios to ensure it is fully functional and safe, even outside normal operation. Methods for the design of cascading flow and ring flow of biogas through the biogas plant are summarized, and a technique of managing the gas storages in a way that the full storage capacity can be used is provided. The findings of this paper are illustrated with examples of two large‐scale industrial biogas plants. [ABSTRACT FROM AUTHOR]