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An integrated micro- and nano-grid with net-zero renewable energy is a sophisticated energy system framework aimed at attaining optimal efficiency and sustainability. This survey paper examines several contemporary research works in this domain. This document summarizes the latest papers selected for analysis to comprehend the current state-of-the-art, integration process, methodology, and research gaps. The objective of this review is to identify existing trends and ongoing transformations in this domain. At the conclusion of the study, emerging technologies for smart grid integration are offered, emphasizing Transactive Control, Blockchain Technology, and Quantum Cryptography, based on existing research gaps. Microgrids and nano-grids are localized energy systems capable of functioning alone or in tandem with larger power grids, offering resilience and adaptability. By incorporating renewable energy sources like solar, wind, and storage devices, these networks can produce and regulate energy locally, guaranteeing that the generated energy meets or surpasses the energy used. The incorporation of intelligent technology and control systems facilitates optimized energy distribution, real-time monitoring, and load balancing, advancing the objective of net-zero energy use. This strategy not only bolsters energy security but also markedly decreases carbon emissions, rendering it an essential element in the shift towards a sustainable and resilient energy future. The worldwide implementation of interconnected micro- and nano-grids utilizing net-zero renewable energy signifies a pivotal transition towards a sustainable and resilient energy future. These localized energy systems can function independently or in conjunction with conventional power grids, utilizing renewable energy sources like solar, wind, and advanced storage technology. Integrating these resources with intelligent control systems enables micro- and nano-grids to optimize energy production, distribution, and consumption at a detailed level, ensuring that communities and companies globally can attain net-zero energy usage. This method not only diminishes greenhouse gas emissions and reliance on fossil fuels but also improves energy security and grid stability in various places. These technologies, when implemented globally, provide a scalable answer to the issues of energy access, environmental sustainability, and climate change mitigation, facilitating a cleaner and more equal energy landscape worldwide. [ABSTRACT FROM AUTHOR]

AbstractMost manufacturing processes for materials from cellulose-based materials deal with huge amounts of water, the interactions of water within the raw material (cellulose) both enable exciting properties as well as limit the rates of production. In the production of tissue paper materials, water content in the pulp is as high as 99.8% when fed into the paper machine, and almost all this water must be removed efficiently and fast. This work presents Novel, easy-to-use, numerical models for predictions of the dewatering of tissue in high vacuum suction boxes and through air drying (TAD) molding. The numerical models were based on and compared with previously published experimental results of vacuum dewatering from laboratory equipment and validated against four separate pilot paper machine trials. The purpose of this study was to establish an accurate, easy-to-use numerical model varying fiber- and machine parameters used in tissue manufacturing to enable the evaluation of new materials and dewatering strategies for energy efficiency investigations. The results indicate that the developed dewatering model could predict the dewatering behavior for both conventional vacuum dewatering and TAD molding using the same set of fitting parameters. The method of developing the numerical models presented can be used for machine optimization and energy efficiency improvements of vacuum dewatering elements in papermaking processes in general. [ABSTRACT FROM AUTHOR]

Amid growing energy demands, innovative solutions are essential to power a variety of devices. Paper‐based microfluidic fuel cells (PμFCs), powered by eco‐friendly alcohols derived from biomass, present a promising option. While lightweight and disposable, they mainly rely on costly noble‐metal catalysts for high efficiency. In this context, the concept of photo paper batteries (pPBs), utilizing affordable sunlight‐activated semiconductors to drive alcohol oxidation on paper, opens the possibility to disposable and affordable energy solutions. Our review highlights recent progress in PμFCs fueled by alcohols like methanol, ethanol, ethylene glycol, and glycerol. We explore semiconductor advancements driving anodic reactions and envision the potential of pPBs. To achieve practical pPBs, refining semiconductors, electrode design, and microfluidic engineering are pivotal. This short review highlights the transformative potential of pPBs and beckons researchers to partake in shaping this new field. [ABSTRACT FROM AUTHOR]

AbstractIn the rapidly evolving wireless communication landscape, achieving full-dimensional coverage poses a gamut of challenges such as intricacy, high hardware costs and energy consumption. In addressing these issues, reconfigurable metasurfaces are being considered as a potential solution. However, traditional methods of producing reconfigurable metasurfaces via printed circuit board (PCB) technologies possess limitations such as high cost and extended production cycles. Particularly, in the context of large-scale communication scenarios, reconfigurable metasurfaces can also present high energy consumption issues. Therefore, this paper proposes a novel type of intelligent reflection surface (IRS) characterized by lower production costs, reduced energy consumption, enhanced flexibility, ease of manufacture, and superior electromagnetic wave modulation capabilities. The proposed reconfigurable smart metasurface is a paper-based metasurface printed with conductive ink, which uses conductive ink to draw base metal blocks on a flexible substrate, and uses silver-tin as a metal patch between the metal blocks, and the phase response is reconstructed with silver ink. By adjusting the distribution of these metallic patches, we tailor the phase and amplitude distributions to generate specific scattering effects. This paper presents designs of six patterns that yield single-beam and dual-beam, with experimental results aligning closely with simulated results, validating the feasibility of the proposed method. This low-power, low-cost, and efficient IRS is expected to pave a new path for advanced 5 G/6G wireless communication technologies. [ABSTRACT FROM AUTHOR]

Here, a novel paired electrolysis system is constructed, where fluorine-doped tin oxide glass serves as the anode for the water oxidation reaction to produce hydrogen peroxide (H2O2), and cobalt phthalocyanine (CoPc)/carbon nanotube (CNT) loaded carbon paper as the cathode for CO2 reduction to generate CO. This system demonstrates a high overall energy efficiency of 34%, where a faradaic efficiency exceeding 90% for CO2 reduction and 60% for water oxidation to H2O2 have been achieved, demonstrating significant energy savings of nearly 40% compared to the respective half-reaction systems. [ABSTRACT FROM AUTHOR]

It is well-known that energy consumption is increasing around the world on a daily basis. In the construction sector, a highly effective solution for reducing energy consumption involves exploring both modern and traditional buildings designed to adapt to climate changes. One promising approach is to use paper waste and bio-sourced materials as the basis for insulation. The purpose of this study was to improve the sustainability of buildings by using recycled waste materials that have a positive impact on the environment, people, and the economy. A novel insulating material composed of recycled paper waste and Ampelodesmos mauritanicus leaves and fibers was developed and used in non-load-bearing elements. The paper waste was transformed into pulp and mixed with the bio-sourced materials to create a composite material that exhibits excellent insulation properties. The resulting material is lightweight, durable, and cost-effective. Furthermore, different mechanical and thermal analyses were performed on specimens with varying dosage ratios. The results showed that the developed material has good thermal insulation, with a value of 0.027 W/m.K. [ABSTRACT FROM AUTHOR]

Overwintering insects are facing energetic challenges because of food shortage, low temperature, and desiccation stress. Paper wasps of the genus Polistes overwinter as mated adults (gynes) in hibernacula protecting them from predation, snow, and rain but barely from low environmental temperature. In different climates, they face differing overwintering temperature regimes, and therefore they may differ in their energy use. We investigated how much of energy resources built up until autumn is used during diapause dormancy in natural hibernacula by measuring lipid, glycogen, and free carbohydrate content in autumn and early spring in Polistes dominula from temperate European (Austrian) and warm Mediterranean (Italian) climate and Polistes gallicus from Mediterranean climate. Winter energy consumption amounted to ~ 339 and ~ 310 J per wasp in the Austrian and Italian Polistes dominula populations. The smaller Italian Polistes gallicus consumed ~ 247 J. This amounts to 2.62, 2.35, and 1.79 J per day. Of this, the energy demand was mainly fuelled by lipids (84%, 93%, and 90%, respectively), but glycogen stores contributed also considerably (16%, 6%, and 9%). Free carbohydrates decreased only by 0.7%, 1%, and 0.8%. While fat stores seem still sufficient in spring, the wasps depleted most of their carbohydrates. The energy reserves of 396, 400, and 147 J per wasp remaining in spring in the three populations seem sufficient to fuel rest or simple brood care activities for a whole summer but restrict foraging flights to a few hours (~ 3.5–6 h). Results suggest that energy supply might become challenging in expected future climate scenarios. [ABSTRACT FROM AUTHOR]

The pulp and paper industry (PPI) has several opportunities to contribute to meeting prevailing climate targets. It can cut its own CO2 emissions, which currently account for 2% of global industrial fossil CO2 emissions, and it has an opportunity to produce renewable energy, fuels, and materials for other sectors. The purpose of this study is to improve understanding of the decarbonization prospects of the PPI. The study provides insights on the magnitude of needed annual renewal rates for several possible net-zero target years of industrial fossil CO2 emissions in the PPI and discusses decarbonization opportunities, namely, energy and material efficiency improvement, fuel switching, electrification, renewable energy production, carbon capture, and new products. The effects of climate policies on the decarbonization opportunities are critically evaluated to provide an overview of the current and future business environment of the European PPI. The focus is on Europe, but other regions are analyzed briefly to widen the view. The analysis shows that there are no major technical barriers to the fossil-free operation of the PPI, but the sector renovates slowly, and many new opportunities are not implemented on a large scale due to immature technology, poor economic feasibility, or unclear political environment. [ABSTRACT FROM AUTHOR]

This study delves into the dynamic evolution of solids content in a pilot-scale through air drying tissue machine, aiming to enhance comprehension and refine optimization strategies for tissue manufacturing. It focuses on development of solids content throughout the process. Analyzing the interaction between process parameters and solids content provides deeper insights into water removal dynamics. The research employs solid contents monitoring techniques in pilot scale, offering a detailed view of solids content evolution from the wet web's inception to the final tissue product. It significantly highlights the impact of key parameters, particularly pulp refining, on solids content across all positions of the pilot machine. Additionally, the study emphasizes the influence of vacuum system configurations, identifying the relationship between energy expended in the vacuum system and evaporation energy. Furthermore, the results indicate that compression and air displacement dewatering in vacuum boxes are less speed-sensitive compared to heat-driven evaporation in the TAD- and Yankee cylinders. Solid contents at all positions in the tissue machine correlates between various dewatering elements. Optimizing site-specific dewatering and evaporation strategies can potentially save drying energy in the Yankee drying phase which hold promise for enhanced energy and resource utilization, aligning with demands for sustainable manufacturing practices. [ABSTRACT FROM AUTHOR]

In order to study the cutting performance of the straight edge hob and reduce the cutting power consumption model of the straight edge hob, this paper takes the cutting power of the straight edge hob as the minimum goal, and establishes the mathematical model of the optimization design of the straight edge hob based on the composite optimization method. The mathematical model is solved by MATLAB software. At the same time,the mowing characteristics of a roller blade were studied by investigating the relationship between the hob and the coordination of variables such as rotational speed and roller diameter with the mowing parameters. The parameter analysis of straight edge hob before and after structural parameter optimization is generated, and a design method is proposed based on this. After defining the objective function and constraint conditions, the influence of structural parameters on the power consumption and efficiency of the hob was determined by optimising the complex method; this could significantly adjust the hob parameters to lower its power consumption. The energy consumption of the optimized design is reduced by 11.1 % compared with the original scheme, and the optimization effect is remarkable. The results show that the best working parameters of the hob are cutting speed of 1000 r/min, sliding cutting angle and grinding edge angle of 25~30°. Moreover, practical tests demonstrated the feasibility of using the proposed method to design the straight edge hob to improve mowing performance and hob stability. This study can provide parameter foundation and an optimization method for lowering chopping power consumption of the roller mower blade. [ABSTRACT FROM AUTHOR]

A novel approach for paper drying using airborne ultrasound technology is presented. A unique experimental setup is developed, and a systematic study is conducted using 23 factorial design of experiments and Analysis of Variance. Three controlling factors are considered in the experiments including the initial moisture content, basis weight and refining condition. The outcome of the experiments is compared to a previous work on direct-contact ultrasonic drying of paper. The results confirm that similar to direct-contact, for airborne ultrasonic drying, the basis weight/thickness of the sample is the most important factor in ultrasonic drying and it is followed by the effect of initial moisture content. Using linear regression model, a correlation for predicting the total time of ultrasonic drying is provided. Quality of the dried samples is evaluated, and the permeability measurements confirmed the effect of pore characteristics on ultrasonic drying. The analysis for energy consumption reveals that airborne ultrasonic drying is more efficient at higher moisture contents. [ABSTRACT FROM AUTHOR]

As interest in the use of eco-friendly enzymes increases in the paper industry, an energy-intensive industry, the development of a wide range of enzyme application technologies is required. This study evaluated the effects of cellulase on the refining efficiency, fiber properties, and sheet strength of softwood bleached kraft pulp (Sw-BKP). The pulp was enzymedosed with cellulase for 6 h and refined using a laboratory beater for 15 min. The freeness and physical properties of the Sw-BKP fibers were analyzed. The pulp freeness decreased linearly as the refining time and enzyme dosage increased, indicating that the cellulase promotes refining efficiency by inducing fiber shortening and internal fibrillation during refining. Handsheets were prepared from 15-min refined enzyme-dosed and non-enzyme-dosed Sw-BKP. The strengths of the enzyme-dosed handsheets were lower than those of the non-enzyme-dosed handsheets because fiber shortening due to the cellulase activity was dominant during the refining. Therefore, cellulase effectively reduces refining energy consumption. However, it is essential to determine the correct enzyme dosage and refining time to balance the desired refining energy reduction with the resulting paper strength. [ABSTRACT FROM AUTHOR]

• The 2,4-dichlorophenoxyacetic acid is effectively removed by electrocatalytic oxidation. • By activating the lattice oxygen in Ni/WO 2 , a large amount of O 2 − is produced. • The electrocatalytic oxidation of 2,4-dichlorophenoxyacetic acid by Ni/WO 2 is the best at 8 mA cm-2. • The catalyst is simple to manufacture and has a low cost. Electrocatalysis is a promising method for removing harmful substances because it does not involve toxic agents and has low energy consumption. Herein, we have developed a low-cost nickel-tungsten dioxide (Ni/WO 2) grown on carbon paper for the first time. Ni/WO 2 /CP demonstrates remarkable catalytic efficiency for the electrocatalytic oxidation of 2,4-dichlorophenoxyacetic acid (2,4-D), achieving a conversion rate of 100 % within 3 h and a total organic carbon (TOC) removal rate of 57 %. After four reaction cycles, the electrode can still achieve a conversion rate of 90.49 %. The exceptional activity of Ni/WO 2 could be attributed to the activation of lattice oxygen in WO 2 by coupled Ni, leading to the generation of a significant amount of superoxide free radicals (O 2 −) and creating numerous oxygen vacancies that serve as the active sites for subsequent 2,4-D oxidation. This work highlights the impact of lattice oxygen on electrocatalytic oxidation and material modification, offering a noble metal-free catalyst for converting harmful substances. [ABSTRACT FROM AUTHOR]

In the field of intelligent transportation, the planning of traffic flows that meet energy-efficient driving requirements necessitates the acquisition of energy consumption data for each vehicle within the traffic flow. The current methods for calculating vehicle energy consumption generally rely on longitudinal dynamics models, which require comprehensive knowledge of all vehicle power system parameters. While this approach is feasible for individual vehicle models, it becomes impractical for a large number of vehicle types. This paper proposes a digital model for vehicle driving energy consumption using vehicle speed, acceleration, and battery state of charge (SOC) as inputs and energy consumption as output. The model is trained using an optimized CNN-BiLSTM-Attention (OCBA) network architecture. In comparison to other methods, the OCBA-trained model for predicting PHEV driving energy consumption is more accurate in simulating the time-dependency between SOC and instantaneous fuel and power consumption, as well as the power distribution relationship within PHEVs. This provides an excellent framework for the digital modeling of complex power systems with multiple power sources. The model requires only 54 vehicle tests for training, which is significantly fewer than over 2000 tests typically needed to obtain parameters for power system components. The model's prediction error for fuel consumption under unknown conditions is reduced to 5%, outperforming the standard error benchmark of 10%. Furthermore, the model demonstrates high generalization capability with an R2 value of 0.97 for unknown conditions. [ABSTRACT FROM AUTHOR]

The article presents studies on the impact of the significant process parameters of a paper machine with a Yankee cylinder on its production capacity and heat energy consumption for drying the paper web. Parameters such as machine speed, web moisture content before and after pressing, parameters of steam supplied to the cylinder and parameters of hot air flowing from the nozzles of the hood were analyzed. The study's results were used to optimize production to improve the energy efficiency and performance of the machine. In order to use the possible methods of improving the production capacity and heat energy consumption, the parameters of the production process were measured and the basic indicators characterizing the operation of the machine were calculated in the Yankee cylinder–dryer hood system. The correct functioning of the machine components and the possibility of their modernization were also analyzed. Technological and construction changes introduced based on the research results made it possible to increase the production capacity by 10% and to reduce the consumption of heat energy per 1 ton of produced paper by 16.3%. The article presents a description of changes in the technology of paper production and modernization of the tissue machine made in the years 2013–2022. [ABSTRACT FROM AUTHOR]

Although there are opportunities to reduce electrical energy demand in unit processes of mechanical pulp-based paper and paperboard production, this may not be financially beneficial. This is generally because energy optimization opportunities connected to reduced refiner electricity demand in mechanical pulping systems also results in less steam available for the drying of the paper. As modern high consistency refiner systems produce approximately one ton of steam for each MWh of electricity when producing one ton of pulp, a reduction in electric energy demand leads to increased fuel demand in steam boilers to compensate for the steam shortage. In this study, we investigated what the financial and environmental situation would look like if we were to expand the system border from a paper mill to a larger system consisting of a mechanical pulp-based paper or paperboard mill, a district heating system with an incineration boiler and a chemical pulp mill. Mechanical pulp production has a wood to product yield of >90%, a high electric energy demand to separate woodchips to pulp and is a net producer of heat and steam while chemical pulp-based production has a wood to product yield of 50%, a low electric energy demand and is a net heat and electricity producer due to the combustion of dissolved wood polymers. The aim of this research is to create useful and robust models of how to use excess heat from certain industry sites to cover the steam shortage in other industry sites by means of utilizing and optimizing the district heating systems connecting these sites. For this purpose, we used a simulation tool which dynamically allows us to evaluate different scenarios. Our results shows that there is great potential to reduce both carbon dioxide emissions and production costs for industry sites and society by means of these tools. [ABSTRACT FROM AUTHOR]

State-of-the-art manufacturing of tissue paper by Through Air Drying provides excellent product performance, although at a high production cost and energy use. In this work, a laboratory scale vacuum suction box was used to mimic the initial dewatering and the Through Air Drying molding, together with a pilot-scale trial. The purpose was to investigate both how the laboratory scale corresponds to pilot scale testing and investigate how fabric design, basis weight, beating, and fibers affect dewatering and sheet caliper. This study reevaluates dewatering mechanisms during molding, challenging the previous hypothesis of pure air displacement dewatering. Results show a parallel mechanism of compression dewatering and air displacement. The influence of rush transfer is examined, impacting the sheets' visual appearance, thickness, and solids content. Correlations between molding box solids content and headbox freeness emphasize significance of fibers and beating levels. Pilot results confirm the link between former solids and molding box solids. Pilot trials validate the laboratory results, facilitating comprehensive simulation of full-scale manufacturing. This research reveals dewatering mechanisms, highlights operational parameters, and enables effective Through Air Drying process design and refinement. [ABSTRACT FROM AUTHOR]

The air-drying of resin impregnated paper sheets in industrial lines, formed by a serial array of furnaces, presents a high number of different controllable operational parameters whose adjustment, usually done by the maintenance staff, leads to non-efficient configurations. A model-based numerical tool, which predicts accurately in a few seconds the evolution of the paper temperature and paper grammage along the line for a given combination of the input operational parameters (direct design), was used coupled to an optimization tool to select appropriate operational parameters (inverse design) that ensure a drying process quality (i.e., fulfills an objective grammage profile) with a minimum of energy consumption. The numerical tool was capable of selecting suitable configurations with an energy reduction of up to 50% for several tested industrial cases, making the model an essential tool in the framework of the increasingly relevant role of digital twins in industry. [ABSTRACT FROM AUTHOR]

Soft robots have promising applications in healthcare, manufacturing, and disaster relief. Inspired by biological models, their superior flexibility and environmental adaptability have increased their use in soft grippers. However, soft grippers often struggle with precise force control and high energy consumption during operation. One solution to these challenges is the utilization of electrostatic adhesion technology. This technology uses electrostatic forces generated by applying a high voltage between electrodes to adhere to objects, allowing for energy-efficient and delicate manipulation. We propose a novel paper-based origami electroadhesive pad (p-OEP) utilizing paper mechatronics. Thin-film comb electrodes were formed through inkjet printing, and self-folding technology was employed to create a structure that adapts to the curvature of the target object. This increases the adhesive area between the p-OEP and object, achieving high strength. This innovative approach expands the application range of soft grippers and provides a new gripping solution that is low-cost and environmentally friendly. [ABSTRACT FROM AUTHOR]

Summary: In the pulp and paper industry, black liquor, which is a biomass resource, is burned to produce electricity. Black liquor is concentrated to 21 wt% water through an evaporator before being burned in a boiler. For the evaporator, a multiple‐effect evaporator (MEE) is mainly used, but it requires a large amount of energy and cost. Therefore, it is crucial to reduce energy and cost of evaporation process. Hence, this study suggested a novel process model that integrated mechanical vapor recompression (MVR) with MEE to increase the energy efficiency. The suggested MVR‐assisted evaporation process was composed of preheating and evaporation processes to effectively concentrate black liquor. In addition, it reduced the steam consumption of MEE by using MVR, which uses relatively inexpensive electric energy in the pre‐evaporation process. In the simulation results, the steam, electricity consumption, and the latent heat recovered from the secondary vapor of the suggested process were quantitatively analyzed to verify the energy efficiency. The results indicate that the proposed process increases substantial energy efficiency compared to the conventional process. Then, the appropriateness of the suggested process was evaluated by the techno‐economic analysis. The total annualized cost (TAC) is determined for both current and potential future economic benefits. TAC of the MVR‐assisted MEE configuration can be reduced by up to 77.54%. [ABSTRACT FROM AUTHOR]

Electrochemical glycerol oxidation reaction (GOR) is a promising candidate to couple with cathodic reaction, like hydrogen evolution reaction, to produce high‐value product with less energy consumption. Two dimensional conjugated metal–organic frameworks (2D c‐MOFs), comprising square‐planar metal‐coordination motifs (e.g., MO4, M(NH)4, MS4), are notable for their programable active sites, intrinsic charge transport, and excellent stability, making them promising catalyst candidates for GOR. In this study, we introduce a novel class of 2D c‐MOFs electrocatalysts, M2[NiPcS8] (M=Co/Ni/Cu), which are synthesized via coordination of octathiolphthalocyaninato nickel (NiPc(SH)8) with various metal centers. Due to a fast kinetic and high activity of CoS4 sites for GOR, the electrocatalytic tests demonstrate that Co2[NiPcS8] supported on carbon paper displays a low GOR potential of 1.35 V vs. RHE at 10 mA cm−2, significantly reducing the overall water‐electrolysis‐voltage reduction by 0.27 V from oxygen evolution reaction to GOR, thereby outperforming Ni2[NiPcS8] and Cu2[NiPcS8]. Additionally, we have determined that the GOR activity of CoX4 linkage sites varies with different heteroatoms, following an experimentally and theoretically confirmed activity order of CoS4>CoO4>Co(NH)4. The GOR performance of Co2[NiPcS8] not only demonstrate superior performance among non‐noble metal complex, but also provides critical insights on designing high‐performance MOF electrocatalysts upon optimizing the electronic environment of active sites. [ABSTRACT FROM AUTHOR]

The document is a guest editorial introducing selected papers from the VIth Modern Power Systems and Units Conference organized by the Department of Energy at Cracow University of Technology in Poland. The conference aims to exchange knowledge on power engineering, heating, renewable energy sources, and other related topics. The special issue of Heat Transfer Engineering journal features papers on various topics presented at the conference, including biomass as a fuel, platinum catalysts in fuel cells, and environmentally friendly water distillation methods. The papers have been reviewed by experts in the field and aim to foster scientific cooperation and fruitful collaboration in the future. [Extracted from the article]

Producing tissue paper is an energy-demanding process; a significant amount of energy is expended when removing water by vacuum, mechanical pressing, and thermal drying. Because the water is most energy-demanding to remove in drying, making the preceding step of vacuum dewatering more efficient would benefit the whole process. This article focuses on developing a laboratory-scale method for verifying the nature of diminishing returns of water removal and investigating efficiency strategies of the vacuum dewatering. The theoretical concept of successive vacuum suction boxes with progressing vacuum levels was tested at the laboratory scale in order to show quantifiable results of the previously solely theoretical concept. The results confirmed that vacuum dewatering can be improved by adding progressively higher vacuum levels and that such a practice can benefit both outgoing dryness levels and expended vacuum pump energy. To truly examine the power of progression of vacuum levels, rewetting can be included in the calculations, by using an approximate value collected from pilot or fullscale measurements. For any new fiber mix, pulp type, vacuum level setup, basis weight, etc. the vacuum levels, rewetting, and dwell times need to be tuned to that specific case. [ABSTRACT FROM AUTHOR]

The energy needed for the dewatering and drying of wet paper web represents around half of the energy consumption of papermaking processes. The present work examined whether the dewatering and drying of paper could be enhanced during a previous pulp drying process by pretreating the fibers with polyamide-epichlorohydrin (PAE). According to the hypothesis, the cured PAE restrains swelling and water absorption of water-wetted fibers by forming a fiber-bound, self-crosslinked polymernetwork on the fiber surfaces. The hypothesis was tested by adding PAE to never-dried kraft pulp slurry followed by pulp thickening, drying, and final curing of the PAE-resin. After this, the PAE-treated fibers were dispersed in water, and their water retention values (WRV) and Shopper-Riegler values (°SR) were measured. The PAE pretreatments notably decreased the fibers' WRV and °SR, indicating improved water removal of paper web in the paper machine forming and drying section. Compared to chemical crosslinking pretreatments, which also can be used to decrease fibers WRV and °SR-value, a notable advantage of PAE-pretreatment is milder required curing conditions of the PAE, which makes implementation of the method easier in practice. Due to decreased fiber-to-fiber bonding capability, the PAE-treated specialty fibers could take advantage especially as a bulking aid of paperboard, tissue, and absorbent materials. [ABSTRACT FROM AUTHOR]

Carbon emissions from the Yangtze River Economic Belt are an important element of China's carbon emission endeavor, and a study of its emission reduction pathway can provide a reference for the country's overall management of carbon emission reduction. From the perspective of energy consumption, this paper uses the carbon emission factor method to estimate the carbon emissions of the transportation industry in the Yangtze River Economic Belt during 2006–2020, based on the extended STIRPAT model, considering the influence of seven factors, i.e., population size, urbanization rate, GDP per capita, transportation added value, energy structure, energy intensity, and transportation intensity, on carbon emissions. Based on these factors, a scenario analysis, combined with a forecasting model, is used to predict the peak carbon performance of the transportation industry under different development scenarios. The results show that the overall carbon emissions of transportation in the YEB from 2006 to 2020 show a fluctuating upward trend, and the downstream carbon emissions are significantly higher than those in other regions. The main factors influencing carbon emissions from transportation in different upstream, midstream, and downstream regions vary, with both population and economic factors contributing to carbon emissions, while technical factors affect them differently. There are significant differences in the peak carbon performance of transportation under different development scenarios, and the government should take effective measures to work towards achieving the goals of the low-carbon or enhanced low-carbon scenarios. [ABSTRACT FROM AUTHOR]

Internet of Things (IoT) architectures generally focus on providing consistent performance and reliable communications. The convergence of IoT, edge, fog, and cloud aims to improve the quality of service of applications, which does not typically emphasize energy efficiency. Considering energy in IoT architectures would reduce the energy impact from billions of IoT devices. The research presented in this paper proposes an optimization framework that considers energy consumption of nodes when selecting a node for processing an IoT request in edge-fog-cloud layered architecture. The IoT use cases considered in this paper include smart grid, autonomous vehicles, and eHealth. The proposed framework is evaluated using CPLEX simulations. The results provide insights into mechanisms that can be used to select nodes energy-efficiently whilst meeting the application requirements and other network constraints in multi-layered IoT architectures. [ABSTRACT FROM AUTHOR]

Recently, as the use of wearable devices and the demand for eco-friendly energy have increased, many studies have been conducted on triboelectric nanogenerators (TENGs), which can economically harvest energy. Paper is considered a promising substrate and frame material that can be used to manufacture self-powered TENGs, owing to its flexibility, low cost, and accessibility. Herein, we present a sandwich-structured foldable paper-based TENG (FP-TENG) that comprises flexible materials and uses paper as a substrate. The FP-TENG can generate up to 572 mW/m2 of power via contact–separation of the triboelectric electrified body at the top and bottom. With more folds of the FP-TENG, the triboelectric cross-sectional area increases, and, thus, the electrical output increases. In addition, the proposed TENG exhibits excellent durability without signal degradation under 5000 cycles of repeated pushing motions. To demonstrate its practicality, the FP-TENG was manufactured in the form of a wristwatch Velcro and connected to an electronic watch panel to supply power. Various deformations are possible with origami, and they can drive wristwatches through external forces. Therefore, the FP-TENG is expected to be utilized as a sustainable and promising eco-friendly energy source for small electronic devices. [ABSTRACT FROM AUTHOR]

Furthermore, very complicated multiphase and thermal processes are the corner stone in modern industry, high technology development, energy conversion and utilization, renewable and sustainable energy technologies, just to name a few here. Therefore, it is essential to develop new technology to improve energy utilization efficient, sustainable energy and low carbon/zero carbon technology to reduce carbon footprint. [Extracted from the article]

Research has revealed the existence of an energy-efficiency gap – the difference between optimal and actual energy end-use, suggesting that energy efficiency can be improved. Energy management (EnM) is a means for improving industrial energy efficiency. However, due to various barriers, the full potential of EnM is not realised. Several studies have addressed drivers and barriers to energy efficiency but few to EnM. This study aims to identify EnM practices, the most important perceived drivers and barriers for EnM, and relations among them in the energy-intensive Swedish pulp and paper industry (PPI), which has the longest experience internationally of practising EnM systems, and has worked according to the standards since 2004. Our results show that, altogether, the PPI works regularly and continuously with EnM, with a clear division of responsibilities. The highest maturity for EnM practices was for energy policy, followed by organization, investments, and performance measurement. The study also shows that communication between middle management and operations personnel has potential for improvement. The most important categories of drivers were economic, whereas for barriers they were organizational. Nevertheless, knowledge-related barriers and drivers were amongst the most important, suggesting that the absorptive capacity for energy issues could be improved. Image 1029 • Energy is managed continuously, with clear policies and responsibilities. • The main drivers are economical while main barriers are organizational. • Knowledge related barriers and drivers are amongst the next most important. • Employees' absorptive capacity for energy issues could be improved. • Link between energy policy and performance measurement could be improved. [ABSTRACT FROM AUTHOR]

In order to achieve an increase in the profitability of tissue paper production, this research aimed to identify factors that affect the degree of pulp refinement and the tension index of the tissue paper when using short fiber, long fiber and Quimizine B enzyme. The methodology considered laboratory experiments, obtaining refining curves, multilevel factorial design and response surface diagrams. The results indicated that the most significant common factor in the pulp refining degree and tension index is the specific energy consumption for both types of fiber, and that optimal operating parameters can be known by analyzing the refining degree and tension index independently and simultaneously. It was concluded that the multilevel factorial design allowed to identify significant factors that influence the properties of the refining degree and the resistance of tissue paper when looking for an individual and simultaneous optimum and, that the influence of the enzyme increased the properties of the refining degree and the tensile strength of the paper when using raw material of short and long fiber from Eucalyptus globulus and Pinus radiata, respectively. [ABSTRACT FROM AUTHOR]

Guiding industries to produce in an effective and environmentally sustainable manner has become a key issue for governments around the world. Over the past 15 years, series of regional and industrial development policies have been introduced by the Chinese government. This has influenced the geographical distribution and energy efficiency performance of China’s industries. This paper quantifies the influence of enterprises geographical distribution on energy efficiency improvement in the paper industry and aims at providing some helpful suggestions on industrial development to policy makers. The main results show that, firstly, the paper industry in eastern China shows obvious characteristic of agglomeration. The average location quotient is 1.2278. However, following the industrial and regional development policies, the characteristic of agglomeration is weakening. Secondly, only when agglomeration reaches a certain level (location quotient is above 0.5447) will industrial agglomeration positively impact on industrial energy efficiency improvement (a 1% increase in agglomeration will increase dynamic energy efficiency by at least 0.23%). Thirdly, the regional development policies carried out by the government slow the pace of energy efficiency improvement in China’s paper industry. The empirical results indicate that the government needs to consider regional characteristics and consciously guide industrial enterprises to concentrate in the dominant area. [ABSTRACT FROM AUTHOR]

The papers analyzed here were presented in the reposts of leading scientists in the processes and apparatuses of chemical technology and published in the Proceedings of the International Scientific and Technical Symposium "Improving the Energy and Recourse Efficiency and Environmental Safety of Processes and Apparatuses in the Chemical Industry and Allied Branches," which was dedicated to the 110th anniversary of A.N. Planovskii and held at Kosygin Russian State University. The scientific areas considered included the development of processes and apparatuses in chemical technology as a science and an educational discipline; the main trends in the theory of engineering of energy- and resource-efficient chemical engineering systems under the conditions of the digital economy; the possibilities of improving the efficiency of mass-transfer processes through the use of contemporary methods for the mathematical modeling and kinetic calculation of apparatuses, intensification, and energy and resource saving; the development of systems of computational fluid dynamics as applied to the spatial calculations of processes and apparatuses; innovative methods for the production of fibrous and nano materials; the fundamentals of methods for the intensification of basic processes in different industrial technologies; the scientific foundations for the creation of energy- and resource-efficient chemical engineering and other processes; considerations of environmental safety for technological processes and equipment; and efficient systems for the improvement of technospheric safety. [ABSTRACT FROM AUTHOR]

With the surging energy price and environmental concerns, measures to improve energy efficiency have attracted increasing concerns of the manufacture sector, especially energy-intensive manufacturing industries such as tissue paper mills. Energy-efficiency scheduling, as a novel energy-efficient method, has attracted the attention of an increasing number of researchers in recent years. Drying process is the most energy-intensive production process in tissue paper mills, which has a great energy-saving potential. This paper aims to reduce the energy costs for the tissue paper mill, consisting of processing energy cost and set-up energy cost, through integrating drying process optimization with energy-efficient scheduling. First, the energy cost model and the scheduling model were built. Then, the energy cost of the drying process of every job in a given scheduling problem was optimized using particle swarm optimization (PSO). Afterwards, the energy cost was further optimized using energy-efficiency scheduling. In addition, a hybrid non-dominated sorting genetic algorithm II (NSGA-II) was utilized to solve the energy-efficiency scheduling problem. Finally, several real scheduling problems from a real tissue paper mill were addressed using the proposed approach to demonstrate its effectiveness in energy saving. The experiment result showed that there is a great energy-saving potential in the drying process, accounting for up to 12.53% of the total energy consumption. Moreover, the maximum energy saving ratio of the proposed approach could reach 9.03%. On the whole, the proposed approach can provide a new energy-saving method for tissue paper mills or other manufacturing industries. [ABSTRACT FROM AUTHOR]

Abstract Papermaking enterprises are currently under both environmental pressure and economic pressure for sustainable development in China. Thus, the efficiency, effectiveness, and benefits of resource utilization need to be improved. High-consumption and high-pollution companies should manufacture paper using sustainable methods. This study highlights a resource value flow analysis from the circular economy perspective, developing an extension of material flow cost accounting and modifying it by accounting for environmental damage as well as economic benefits. With reference to the Plan-Do-Check-Act cycle, this specific case study was conducted to verify the comprehensive utility of resource value flow analysis by establishing decision-making prioritization according to the dualistic diagnosis of "internal resource loss–external environmental damage costs." In general, applying a resource value flow analysis can both reduce resource consumption and minimize environmental damage, enhancing the sustainable development of a process industry with limited resources. Highlights • Material flows and value flows form an interactive unit in the resource value flow analysis model. • The resource value flow analysis model extends the environmental dimension of material flow cost accounting. • A dualistic diagnosis of "internal resource loss and external environmental damage costs" can achieve both economic profits and environmental benefits. • The Plan-Do-Check-Act cycle was introduced to strengthen the practical application of the resource value flow analysis. [ABSTRACT FROM AUTHOR]

As an emerging non-wood resource, moso bamboo has attracted extensive attention because of its short growth cycle and high holocellulose content. However, the internal structure of moso bamboo is more compact than that of wood, leading to higher chemical consumption during the pulping process, which greatly reduces the quality of the extracted fibers. Herein, an innovative pulping system including enzymes and alkali is proposed to achieve higher-quality extraction of moso bamboo fibers. Benefiting from the synergistic effects of high-temperature and alkali-resistant cellulase, xylanase, and laccase, supplemented with alkaline pulping, adequate retention and softening of moso bamboo fibers were ultimately achieved. The sample treated with an enzyme/alkali system resulted in a relative increase in fiber length of 7.19 % and a 31.26 % increase in beating efficiency over alkaline pulping. In addition, the tensile index and tearing index of the paper treated with the enzyme/alkali system reached 50.17 N·m·g−1 and 9.12 mN·m2·g−1, which were 22.52 % and 20.53 % higher than those of the alkaline pulping, respectively. This work provides new insights into the production of high-performance moso bamboo fibers and paper with low energy and alkali consumption. [ABSTRACT FROM AUTHOR]

Electrophoretic display (EPD) has been a prevailing paper-like display technology for years, owing to its advantages of flexibility, low-power consumption, and good sunlight readability. However, it is regrettable that the black/white EPD still dominates the majority of the market while a commercially sold full-color EPD is still unavailable. In this paper, we proposed a facile yet feasible method to fabricate a color EPD by a tape-assisted transfer method, which is the first demonstration using transfer method to achieve color micro-encapsulated EPD. [ABSTRACT FROM AUTHOR]

Excellent mechanical and electrical properties of graphene-based paper-like materials are essential for applications in flexible conductors, energy-storage devices, etc. The graphene oxide (GO) supernatant separated by centrifugation and ultrasonication has been used to prepare graphene oxide paper and reduced graphene oxide paper (rGOP) with high strength and conductivity. However, this method has cumbersome steps and low supernatant concentration, which greatly increases time and energy consumption, and is not suitable for rapid batch preparation of high-strength and high-thickness rGOP. Herein, a high-speed mechanical shearing method has been used to efficiently exfoliate graphite oxide suspension into high-concentration GO slurry with large lateral size, and rGOP has been further prepared by blade coating and HI acid chemical reduction. Compared with the product prepared by ultrasonic exfoliation method, the average area of GO sheets obtained via the mechanical shear exfoliation method can reach around 16.31 μm2. As a result, the mechanical properties and conductivity of the prepared rGOP have been increased by 30% and 23.5%, respectively, with the tensile strength and electrical conductivity of 478.2 MPa and 208.4 S/cm being obtained. The developed method is of great significance for the large-scale production and emerging applications of lightweight and high-performance rGOP. [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]

China’s paper industry consumes a lot of energy and emits huge amounts of pollutions. The Chinese government over the past decades has done a lot to promote energy efficiency of the industry. This paper studies the impact of industrial polices to improve energy efficiency. The energy efficiency change is firstly studied under a framework of total factor efficiency. On this basis, different econometric models are built to discuss the detailed energy efficiency characteristics of the paper industry. The main results are as follow: (i) ownership structure did influence the energy efficiency, but the influence is different in different conditions; (ii) energy efficiency of the paper industry can be improved by economies of scale; (iii) market competition can to some extent overcome the motivation and supervision problem that often occur in state-owned companies; (iv) energy price cannot play the role of resource allocation well in China. Finally, based on our findings, some suggestions are provided. [ABSTRACT FROM AUTHOR]