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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]

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]

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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

China is the top emitter of greenhouse gases in the world. Pulp and paper industry is one of eight the strictly regulated industries about carbon emission in China. However, estimates of carbon emissions from China's pulp and paper industry have been suffered from remarkable uncertainty. It is summarized that is aroused by the inaccuracy of factors evaluating energy consumption, and the huge gap between the calculation standards for assessing energy consumption in the production process and the actual level recorded in the factories. This paper re-evaluated the carbon emission of China's pulp and paper industry from the perspective of life cycle assessment, and applied more accurate emission factors, taking account of the actual energy consumption of the production process in factories, to estimate the actual carbon emissions in maximum. It is found that the national standards about the energy consumption quota of China's pulp and paper industry is no longer applicable, and the actual energy consumption regulated in the production process is far better than the advanced level given by the national standards. The greenhouse gas emission have been seriously overestimated approximately 12.00%–56.17% by international organizations. • Life Cycle Analysis of the China's pulp and paper Industry is conducted thoroughly. • The pulp flow of China's pulp and paper Industry is analyzed. • Energy regulated in factory is far better than the national standards' required. • Carbon emissions of China's pulp and paper Industry are overestimated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrafine marble dust waste particles were obtained using the top–down approach. • Waste and by-products had positive effect on dry grinding of stone wastes. • It is economically feasible, also environmentally friendly. • These obtained ultrafine particles can be used effectively mineral filler in many areas. Waste management in marble processing plants is a considerable problem in countries with developed stone industries and trade. Research on the utilization of stone waste in different fields is still continuing. However, there are few studies on using this stone waste from processing plants as mineral fillers. Moreover, no study in the literature has investigated the influence of grinding aids on stone properties. The current research is the first to compare of the efficiency of different grinding aids on the waste calcitic and dolomitic marble in the production of mineral fillers. The objective of this work is to research the impacts of waste and by-products on the dry grinding of stone wastes as grinding aids in a vertical stirred media mill. The results were assessed in terms of various parameters: product particle size, powder flowability, material coating on the grinding media, and energy consumption. Remarkably, the study showed that the use of any of the grinding aids tested enhanced the grinding process in comparison with the no-aid condition. The best product fineness value was achieved with pomace oil followed by the by-product glycerin, among the grinding aids tested in both samples. Moreover, a higher media coating reduction and the highest energy saving were achieved with pomace oil. The most significant and lowest increase in the fluidity index was achieved with pomace oil and paper wastewater, respectively. Additionally, the Fourier transform infrared spectroscopy (FTIR) performed to reveal the interaction between particle surfaces and grinding aids demonstrated the activity of pomace oil and glycerin polar functional groups on particle surfaces. The analysis of the agglomeration phenomenon with SEM (scanning electron microscopy) micrographs showed that particle agglomeration could be eliminated with the pomace oil. Thermogravimetric analysis (TGA) was used to investigate changes in the mass of the samples' due to temperature changes. With this study, a significant contribution will be made to the ecosystem using waste marble powder whose storage problematic. [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]

Arid areas account for more than 20% of Earth's surface. Many of these arid areas suffer from harsh climates where energy consumption is high and production coexists with high hydrological stresses. In such areas, the production of water is directly linked to the production of electricity, bringing the Energy–Water nexus to a higher level [Heggy et al., Sustainable Energy-Water-Environment Nexus in Deserts (Springer, 2022)]. Under the current energy transition from a fossil-based economy to a renewable energy-based system, arid areas are seen as potential reservoirs for electricity production due to their high solar potential, thereby helping to achieve global decarbonation targets. This energy production transition will strongly affect the Energy–Water nexus as it will contribute to the decoupling of electricity from water production. The International Conference on Sustainable Energy–Water–Environment Nexus 2019 (ICSEWEN19) conference was the first to address the Sustainable Energy–Water Nexus in Deserts, bridging the gap between research and industry and highlighting the research capabilities relevant to Qatar, the region, and internationally. The Invited Papers from the International Conference on Sustainability, Energy, Water, and Environment Nexus in Desert Climates Special Collection in Journal of Renewable and Sustainable Energy presents articles covering the main elements of the conference with respect to solar photovoltaic implementation in desert environments as a key element to succeed in this global energy transition. [ABSTRACT FROM AUTHOR]

Aluminum powder particle size (D50) is quite important for how to improve the energy release level and formulation design of aluminized explosives. In this paper, four experimental samples of CL-20-based aluminized explosives with aluminum powder particle sizes including 2, 13, 24, and 43 μm were designed. The experiments were carried out through an underwater explosion tank and compared with explosives containing lithium fluoride of the same particle size. The results show that the burning of aluminum powder promoted the shock wave propagation and bubble expansion. Aluminized explosives have a lower and then higher decay rate than lithium fluoride-containing explosives. For the experimental range of aluminum powder particle sizes, with an increase in D50, the peak shock wave pressure first increased and then decreased, reaching the maximum at 24 μm; the shock wave and loss energy gradually increased, while the bubble energy, energy utilization, and underwater explosion total energy all gradually decreased. To a certain degree, the energy output structure can be regulated by adjusting the D50 under the premise of constant total energy of explosives. The experimental results improve our understanding of how D50 affects the underwater explosion parameters of aluminized explosives, which is of great significance for improving their energy utilization. [ABSTRACT FROM AUTHOR]

There is an urgent need for energy sources with lower environmental impacts to dispose of waste generated by human activities. In this context, a holistic analysis of energy use of waste from agricultural and forestry activities, animal excreta, urban solid waste and sewage, waste from the pulp and paper industry and charcoal in Brazil is presented. Based on a bibliographic review, the current Brazilian panorama is presented in figures giving, a vision of national potential for harnessing bioenergy from this theoretical and technical potential. The QGIS3.24.2 Tisler geoprocessing tool was used to generate potentiality maps from census data of microregions and municipalities available in the IBGE database (2022) and in the Geocentric Reference System for the Americas (SIRGAS 2000). The results of map analysis by micro‐regions of the primary energy from agricultural residues highlight sugar cane, corn and soybeans crops, followed by wastewater and animal excreta. They stood out amont the studied sources of biomass with technical potentials of 53.17, 15.23 and 6.81 GW, respectively. With these results, it is concluded that Brazil could enable around 75 GW installed power, reusing all biomass, potentially 12.5 PJ, without considering the 16 GW already installed from sugarcane and paper black liquor plants. [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]

In this paper, a wideband metasurface-loaded (MTS-L) rectenna system is proposed to capture electromagnetic (EM) energy at arbitrary azimuth angles. The radiation patterns of different modes in the original MTS configuration are analyzed using the characteristic mode theory, and potential modes with omnidirectional radiation are screened out. By the arrangement of patches, the roundness performance of the radiation pattern can be ameliorated, and the omnidirectional characteristic is obtained over a wide frequency band. Subsequently, the surface current density of the selected mode is carefully and artificially designed to facilitate probe excitation as well as refrain from introducing complex power-combining networks. A wideband rectifier circuit is designed as the load of the proposed antenna. Eventually, measured results show that it operates from 4.6 to 9.6 GHz with a fractional bandwidth of 70.4%, and the peak system efficiency is 52.2%. The proposed system demonstrates excellent potential for wireless power transmission and EM energy harvesting in indoor environments. [ABSTRACT FROM AUTHOR]

The research assessed waste-based briquettes consumption compared to conventional fuels in the Andes. Laboratory tests were conducted together with on-field analysis in Colquencha (Bolivia). The laboratory study shows that the performances of briquettes are better in terms of PM2.5 (933.4 ± 50.8 mg kg−1) and CO emissions (22.89 ± 2.40 g kg−1) compared to animal dung (6265.7 ± 1273.5 mgPM2.5 kg−1 and 48.10 ± 12.50 gCO kg−1), although the boiling time increased due to the lower fuel consumption rate and firepower compared to shrubs. The social survey organized with 150 Bolivian citizens suggested that low-income households are not able to pay for an alternative fuel: about 40% would pay less than 4 USD per month, while methane use for cooking is positively correlated with the income level (r = 0.244, p < 0.05). On field analysis suggested that local cookstoves are not appropriate for briquettes combustion since indoor air pollution overcomes 30 ppm of CO and 10 mgPM2.5 m-3. On balance, local small manufactures can be the main target for selling waste-based briquettes to reduce shrubs and wood consumption. However, briquettes production costs seem not yet competitive to natural easy-to-obtain fuels (i.e., animal dung). The research encourages the use of cellulosic and biomass waste-based briquettes in the Andean area for cooking, heating, or manufacturing and strongly advises policy-makers to introduce economic incentives for the recovery of secondary raw materials. • Analysis of waste-based briquettes use in Andean areas were conducted. • Laboratory analysis, social surveys, and on field evaluations are the methods. • Briquettes can be employed for reducing about 30% of the conventional fuels. • The research encourages the employment of waste-based briquettes in the Andes. • Incentives to briquettes production and consumption should be introduced. [ABSTRACT FROM AUTHOR]

The University of Alcalá in Madrid will organize the "III International Congress on Green Public Procurement and Climate Change" on October 4th and 5th, 2023. The congress aims to receive oral communications on topics related to green public procurement and climate change, as well as tangential aspects such as sustainable food, legislation on climate change, public procurement and depopulation, sustainable infrastructure and energy efficiency, and sustainable or low-emission mobility. The Scientific Committee will review the communications and select the best ones for possible publication in the journal Actualidad Jurídica Ambiental. The deadline for submitting abstracts is May 15th, 2023. [Extracted from the article]

AbstractThe distinctive pharmacological characteristics of Chinese medicinal herbs are rendering them increasingly popular as functional foods. However, fresh herbs are prone to mold and decay. Currently, drying processing is primarily employed to extend the storage time and effectively preserve the bioactive constituents of these herbs. After examining of the recent literatures on drying Chinese medicinal herbs, this paper provides a comprehensive overview of various drying technologies, including shade drying, hot air drying, solar drying, heat pump drying, microwave drying, far-infrared drying, vacuum drying, vacuum freeze drying, radio frequency drying, high voltage electric field drying and some combined techniques. While, an extensive illustration for each drying method principles, advantages/disadvantages, potential improvements and deep investigation of its energetic performance and the influence on the main active components in the drying process, such as polysaccharides, polyphenols, flavonoids, saponins, volatile oils, were summarized. The results showed that the combined drying technology not only had high efficiency and low energy consumption, but also preserved the bioactive medicinal components and sensory quality at the best. This paper provides a theoretical foundation and vast technical support for enhancing the value of Chinese medicinal herbs utilization and drying industry. [ABSTRACT FROM AUTHOR]

This research addresses the issue of the heritage preventive conservation in the perspective of energy sustainability, for contributing to the achievement of the Sustainable Development Goals (SDGs) and towards the EU Green Deal. The study analyses and compares four cases associated with different microclimate thresholds as suggested by the standard EN 16893:2018 (Cases 1–3) and as derived from the outputs of three degradation models for preserving paper, wood, and canvas paintings (Case 4). Weather-based indices (degree and gram days) were calculated to estimate trends in the potential energy demand of collection facilities in three European cities belonging to different Köppen-Geiger climate zones (Cfb, Csa, and Dfb), under recent past (1981–2010) and near/far future climate scenarios (2021–2050 and 2071–2100) from two Shared Socioeconomic Pathways (SSP2-4.5 and SSP5-8.5). The findings suggest that adapting facilities' management strategies to focus on collections preservation can facilitate the achievement of 5 out of 17 SDGs, offering a viable alternative to costly energy retrofits and encouraging the development of shared solutions for similar facilities in the same climate zone. The results can contribute to inform the revision of EN 16893 and to face major challenges such as the preservation of paper collections in southern latitudes. [ABSTRACT FROM AUTHOR]

With the development of society, non-renewable energy such as oil and natural gas are gradually consumed and exhausted, and the energy crisis has become the biggest resistance to the development. Therefore, the development of New Energy (NE) has become an important issue for the Sustainable Development (SD) of modern society. Distributed NE system is the new direction of modern energy development. Therefore, higher requirements are put forward to improve the performance of distributed NE systems. The traditional NE system is relatively scattered and cannot be used intensively. There is no consensus among various NE systems, and the energy utilization is insufficient. It leads to a great waste of energy in the process of developing and using NE. The introduction of Blockchain Technology (BT) has contributed to solving many practical problems. BT can not only ensure the authenticity of data but also meet the requirements of high quality by taking advantage of its own characteristics of data tamperability and traceability mechanism. The Consensus Algorithm (hereinafter indicated by CA) in the blockchain ensures that the final results received by all participants are consistent and error-free through data synchronization, and distributed, consistency cooperation. The access of distributed NE solves the disadvantage that the traditional NE system cannot be used in a centralized way, to access NE more efficiently, conveniently, and quickly. In this paper, the distributed NE system was accessed based on the blockchain CA. By adopting BT and CA, a distributed NE system that was easy to access was established. The system could systematically deploy the existing developed NE and then make centralized use of it. This paper compares the efficiency, stability, and loss of access of the distributed NE system using the blockchain CA with that of the traditional distributed NE system. The results showed that the use of blockchain CA to access distributed NE could effectively utilize NE, and the efficiency of distributed NE access after using blockchain CA increased by about 28.8 %. At the same time, the experimental results showed that the access stability was high and the access loss was low. With the continuous development of NE, the blockchain CA would gradually become an important technical support in the energy field, thus promoting the overall development of the energy industry. [ABSTRACT FROM AUTHOR]

With the development of science and technology, the energy issue has gradually become a topic of global common exploration. According to the relevant information, this paper designed a distributed new energy system based on the blockchain consensus algorithm. The system took the distributed new energy system as the main body, integrated it with blockchain technology, and finally formed a distributed new energy system based on blockchain consensus algorithm. The feasibility of the system was finally determined after the technical tests of voltage detection, power allocation, information collection, and algorithm security. In order to understand the differences between the performance of this system and the traditional system, this paper has made several performance data comparative analysis tests for this system and the traditional system. The test items included energy conversion utilization rate, energy storage, energy use price, energy cleanliness, energy access rate, energy use, etc. Finally, the relevant data of commercial power consumption and residential power consumption accounting for 30 % and 47 % of the total power consumption were obtained, and the data was used to analyze the source of power access. The proportion of green energy is 10 % and 17 %, respectively. According to a series of operation processes such as design, experiment, and analysis, it was finally determined that the system was feasible and effective. [ABSTRACT FROM AUTHOR]

Consensus mechanism (CM) is the heart and soul of blockchain, for it allows nodes in a blockchain network to reach an agreement on the state of system execution. Among the CMs, the right for constructing the next new block is regarded as the most important one since it is required for the blockchain to grow so that transaction data can be recorded in it. Proof-of-work (PoW) is an efficient CM since it allows all the nodes to participate equally in the competition for the right. However, high energy consumption makes PoW less desirable for applications. Moreover, application-oriented blockchains should employ CMs that could reflect some main characteristics of the applications to facilitate the development of other mechanisms, such as the incentive mechanisms. Proof-of-contribution (PoC) is an effective, application-oriented CM since the right for constructing the next new block is determined by contributions made by the nodes and the node that has accumulated the highest contribution value (CV) gets the right. PoC is a general-purpose CM since the behavior of nodes can be characterized in the form of contributions. However, the deterministic nature of PoC as the result of ranking nodes based on CVs may lower efficiency since nodes could fail to function due to network delay, node failure or node's simply dropping out of the network. This paper proposes to design highly effective and efficient CMs by integrating PoC with PoW, which we refer to as PoCW. In PoCW, nodes compete for the right for constructing the next new block based on PoW after being assigned different difficulty values (DVs) based on the ranking of their CVs. Since assigning DVs strictly according to the ranking of CVs would make PoCW resemble PoC while assigning the same DV to all the nodes would make PoCW the same as PoW, PoCW could be designed as a class of CMs through applying different DV assignment strategies to meet the effectiveness and efficiency requirements of a variety of applications. We can further apply the same principle at finer levels of granularity by dynamically grouping nodes along the ranking of CVs and then applying different DV assignment strategies to different groups. The paper will first describe a generic PoCW without involving node grouping and then present the design of a general PoCW through applying an example node grouping method to demonstrate the feasibility of PoCW as a general-purpose CM for blockchain-based applications. Experiments were also conducted to demonstrate the effectiveness and the efficiency of PoCW as well as its advantages over comparable CMs. [ABSTRACT FROM AUTHOR]

To enhance the power supply reliability of the microgrid cluster consisting of AC/DC hybrid microgrids, this paper proposes an innovative structure that enables backup power to be accessed quickly in the event of power source failure. The structure leverages the quick response characteristics of thyristor switches, effectively reducing the power outage time. The corresponding control strategy is introduced in detail in this paper. Furthermore, taking practical considerations into account, two types of AC/DC hybrid microgrid structures are designed for grid-connected and islanded states. These microgrids exhibit strong distributed energy consumption capabilities, simple control strategies, and high power quality. Additionally, the aforementioned structures are constructed within the MATLAB/Simulink R2023a simulation software. Their feasibility is verified, and comparisons with the existing studies are conducted using specific examples. Finally, the cost and efficiency of the application of this study are discussed. Both the above results and analysis indicate that the structures proposed in this paper can reduce costs, improve efficiency, and enhance power supply stability. [ABSTRACT FROM AUTHOR]

The electrification of commercial vehicles has led to new wheel torque allocation options for propulsion and braking of articulated heavy vehicles. Each unit or axle can be individually braked or propelled whilst the other units or axles are excluded from such action. This may achieve the best energy efficiency. However, this can also lead to potential yaw stability problems such as jackknifing and trailer swing, especially under bad loading and weather conditions. This paper describes the above instabilities and introduces a nonlinear single-track model to study the vehicle dynamics of the tractor-semitrailer combination. The effects of different vehicle and environment parameters are analysed with this vehicle model. A safe operating envelope for limiting the wheel forces is obtained using this vehicle model. Since the vehicle model introduced in this paper is computationally effective, it can be run online in real vehicles, with an instantaneous safe operating envelope obtained for the momentary conditions. Thus, yaw instabilities such as jackknifing and trailer swing may be avoided. [ABSTRACT FROM AUTHOR]