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Industrial process heat decarbonization through electrification could contribute significantly to climate change mitigation efforts. In the US industry, thermal processes accounted for more than two-thirds of the total final energy demand in 2021. Cross-cutting electrification technologies like industrial heat pumps are suitable for the process heat supply to several industrial unit operations in a sustainable way while also improving overall energy efficiency. This study employs a bottom-up approach to investigate the techno-enviro-economic potentials of deploying high-temperature and steam-generating heat pumps in US textile, pulp and paper, and automotive sectors in different timeframes. The results show that the annual technical potential energy and CO2 savings by electrifying heat supply are 310 PJ (or 36% of the projected energy demand) and 28 MtCO2 (or 71% of the projected CO2 emissions) in 2050 respectively, however, these incur additional costs in each sector (ranging between 5 and 18 $/GJ). The required heating capacity of industrial heat pumps is estimated at 15 GW, which translates roughly into a market of over 6000 heat pump units and an investment volume of $7 billion in the studied processes. Although there may be individual cost-effective opportunities for electrifying heat supply in specific industrial sites, the overall costs are estimated to be high in the three industrial sectors due to the large disparity between electricity and natural gas prices and low heat source temperatures. To overcome the identified techno-economic barriers, comprehensive action plans for different stakeholders are also given. This study provides novel insights that should inform policymakers’ and executives’ decisions about the electrification of the current and future US industrial heat supply in relevant industrial sectors.

This paper reports the improved model of a tempering machine for heating the formulation mixture of marshmallow, characterized by heat supply to the working tank through the replacement of a steam jacket with heating by a film resistive electric heater of radiative type (FREhRT). The surface of the heat exchange of the device was increased by heating the stirrer with FREhRT; secondary energy (30....85°C) was used by converting it by Peltier elements for the autonomous operation of superchargers for cooling the engine compartment. The proposed solution will lead to an increase in the efficiency of the device, which is explained by a decrease in its specific metal consumption through the use of FREhRT. A reduction in the duration of heating (75°C) a marshmallow formulation mixture was experimentally established: in the examined model, 530s, compared with the analog, 645s. That confirmed the reduction in heating time to the set temperature by 21.7% compared to the MT-250 basic design. The calculations have established a decrease, by 13%, in the specific energy consumption for heating the volume of a unit of product when using the improved structure, 205.7kJ/kg, when using the basic one ‒ 232.1kJ/kg. The increase in the efficiency of the proposed structure is explained by a decrease in the specific metal consumption of the device from 474kg/m2in the base apparatus to 273kg/m2in the improved one. The study results confirm the increase in the resource efficiency of the improved tempering machine, which is achieved by eliminating the steam jacket; increasing the heat exchange surface by heating the stirrer. The heat transfer by FREhRT simplifies the operational performance of the temperature stabilization system in a working tank. The reported results could prove useful when designing thermal devices with electric heat supply under the conditions of using secondary energy, which is relevant for ensuring resource efficiency

In industrial engineering, hydrogen is usually transported and stored after being liquefied, which is an energy-intensive process. Aiming to liquefy hydrogen with high efficiency and low consumption, a novel hydrogen liquefaction process based on dual-path hydrogen refrigeration is proposed innovatively and simulated by Aspen HYSYS to determine the key parameters. Taking the specific energy consumption (SEC) as the objective function for the optimization by genetic algorithm (GA), optimum parameters could be obtained. Meanwhile, the single variable method is conducted to analyze the impact of key parameters on process characteristics. Under the premise of complete liquefaction, the SEC, coefficient of performance (COP) and exergy efficiencies (EXE) of the proposed system are 7.041 kWh/kg LH2, 0.1834, 0.5413, respectively. Compared with the other three hydrogen liquefaction systems simulated under the same conditions, they are decreased by 22.16% and increased by 33.58% and 42.37%, respectively. The results show that the proposed system shows better performance under lower consumption.

This study proposes the integrated designs of energy systems and a re-liquefaction system for ocean-going LH2 tankers. Five prospective energy systems (Systems A to E) are suggested, using LNG as fuel, and a re-liquefaction system with a Claude cycle is developed. Their economic value, technological feasibility, and environmental impact are evaluated. The re-liquefaction systems' exergy efficiency and specific energy consumption ranges were 26.79–46.27% and 3–7.45 kWh/kg, respectively. The re-liquefaction system in System C is economically feasible up to $2/kg of H2. LCC of the integrated designs shows that System C has the lowest cost of $140 million. The shipping costs for each design are reviewed, and the lowest one is $447/ton of H2 for System C. Although System C CAPEX is the second expensive, it has the highest efficiency. Consequently, System C with the low-pressure engine, SOFC, and the re-liquefaction system is determined to be the optimal one.

This paper reports the improved model of the unit for melting cheese masses. The device differs in the technique of heat supply to working tanks through the replacement of a steam jacket with heating by a flexible film resistive electric heater of radiative type (FFREhRT). The heat exchange surface of the working container was increased through heating the mixing device by FFREhRT. In addition, the unit is distinguished by utilizing secondary thermal energy of melting cheese masses (35...95°C) by converting it with Peltier elements into a low-voltage power supply to autonomous fans (3.5...12W) in order to cool the control unit. Such a solution would improve the efficiency of the proposed structure, which is explained by reducing the dimensional and weight parameters of the cheese melting unit by replacing the steam heating technique with an electric one. A decrease in the time to enter a stationary mode (85°C) when melting cheese masses was experimentally confirmed: for the bowl of the examined unit ‒ 575s, compared to the analog ‒ 725s. That confirms the reduction in the time to enter a stationary mode by 21% compared to the base unit B6-OPE-400. The estimation has established a 1.2-time decrease in the main indicator of resource efficiency of the specific energy consumption for heating the volume of a unit of product in the improved plant for melting cheese masses – 3,037.2kJ/kg, compared to the base B6-OPE-400 – 3,672.5kJ/kg. The results confirm an increase in resource efficiency that is achieved by the elimination of steam heat networks; the increased heat exchange surface of working bowls by heating the stirrer with the help of FFREhRT. The heat transfer that employs FFREhRT simplifies the operational indicators of the temperature stabilization system in the bowl of the cheese mass melting unit. The results reported here may prove useful when designing thermal equipment with electric heating while using secondary thermal energy.

This paper firstly proposed using ice abrasive water jets (IAWJs) to slot coal seam to ensure the safe exploitation of coal mines. The performances of IAWJs, pure water jets (PWJs) and conventional abrasive water jets (CAWJs) breaking coal were simulated and compared using the coupled SPH-FEM methodology. The findings indicate that the breaking performance of coal samples subjected to abrasive water jets are more obvious than those of coal samples subjected to PWJs, while the performance achieved by CAWJs is slightly more evident than that by IAWJs. Most of the ice particles transformed into pure water after impacting and then flowed away with the backflow, while many abrasives remained in the coal under CAWJ impact. The specific energy consumption of breaking coal by IAWJs is obviously lower than that consumed by PWJs and CAWJs. Accordingly, it can be inferred that IAWJ is a promising technology in coal slotting applications

— Energy demand forecasting plays a key role in solving the majority of problems connected with determining the economic and energy development prospects. In view of high inertia and capital intensity of energy generation facilities, the changes in the energy consumption structure and rates should be considered for a sufficiently long-term future of no less than 15 years. This adds much difficulty to the development of such forecasts, because it is necessary to take into account the possible results of technological progress in different sectors of the economy and changes in its structure. The suggested approach to energy demand forecasting is based on the systems analysis methods. Energy consumers are disaggregated by economic sectors, country regions, energy carriers, and their utilization areas. As a result, it becomes possible to take into account the possible future technological and structural changes in the economy, its differences in different regions, mutual replacements of energy carriers, and energy saving. The most important feature of the approach is that it involves the separation of economic and energy variables. Economic variables determine the development scales of economic sectors, and energy variables determine the energy consumption intensities in them. The separation of variables helps obtain essentially more accurate forecasts owing to the possibility of taking into account the differences in the variation trends of these variables in the forecast period. For forecasting the economic variables, a nonlinear conditionally dynamic model of interrelations between the economy and energy is used. The energy variables are forecasted on the basis of their links with economic factors, e.g., with cumulative investments in the fixed capital of the considered economic sectors. The discussed approach was implemented as the totality of adaptive simulation models united into the EDFS computing system. The approach was repeatedly and quite successfully used to forecast the energy demand for an up to 10–20-year horizon in solving various problems. The gained experience has demonstrated the correctness of applying the approach for solving long-horizon forecast problems. To illustrate the capacities of the approach, the electric energy demand forecast for the period of up to 2040 for the basic version of the social and economic development of Russia’s economy prepared on the basis of this approach is presented.

The selection of a proper drying method can play a vital role in reducing the energy consumption and the quality of the final product. In this study, three dryers, including conventional refractance window (CRW), solar refractance window (SRW) based on the photovoltaic-thermal system, and hot air (HA) dryers, were used to dry the Aloe vera gel. Experiments were carried out at four levels of temperature (60, 70, 80, and 90 °C) and three levels of thickness (1, 2, and 3 mm) for the puree product. An increase in temperature and a decrease in thickness reduced specific energy consumption, specific heat consumption, specific heat utilization, pollutant emission, and social costs derived from the pollutant. The results showed that the SRW dryer significantly improved the energy and drying parameters compared to the HA method. The pollutant emission and social costs in the SRW dryer were zero, while these values were significant using the CRW and HA dryers. The highest amounts of antioxidant potential, phenol, flavonoids, and glucose were 98.61%, 0.0435%, 0.0103%, and 19.28% (mg/g dry matter), which were obtained at 60 °C and 3 mm thickness using the SRW/CRW dryers. However, these values were 76.69%, 0.0246%, 0.0039%, and 16.31% (mg/g dry matter) using the HA dryer. In general, according to energy consumption and drying parameters, the best experimental results were obtained at temperatures between 70 and 80 °C and a thickness of 2 mm.

Electrohydrodynamic (EHD) drying is considered a highly efficient technology due to its ability to create powerful convective airflow with low energy consumption. EHD efficiency depends on multiple...

The fluidized bed technique was applied to use with the Robusta coffee in this research. fluidization behavior and specific energy consumption were investigated under various coffee forms and distributor hole angles. Moreover, the minimum fluidization velocity (Vmf) was also determined. Experiments are carried out in a sample bed height of 5 cm with ambience air. In this study, two coffee forms (Ripe coffee cherries; RCC and parchment coffee; PC) and three distributor hole angles (45º, 60º and 90º) are examined. The experimental result shown that the fluidization behavior is influenced by coffee form and distributor hole angle. The RCC and distributor hole angle of 60º provided the low pressure drop throughout the superficial air velocity. The low values of Vmf and SEC were also achieved in the RCC and distributor hole angle of 60º.

Вступ. В умовах існуючої кон’юнктури ринку, коли попит на металургійну продукцію залишається сталим або знижується, розвиток металургійної галузі можливий за рахунок оптимізації операційних витрат. Оскільки значною складовою собівартості готової продукції є витрати на електроенергію, середній темп зростання цін на яку за останніп’ять років склав 125 %, виникає необхідність у виконанні аналізу енергоспоживання з подальшою його оптимізацією.Проблематика. В діючій технологічній лінії виробництва коксу найбільш енергоємною технологічною операцією є подрібнення вугільної шихти, в якій не передбачено попереднє відсівання готового класу. Аналіз гранулометрично­го складу вугільних концентратів показав, що вхідна шихта містить лише 12,5 % фракцій, які потребують дроблення. Зважаючи що, валовий потік вугільного концентрату надходить до дробарок, це призводить до того, що коефіцієнт корисної дії використовуваних дробарок не перевищує 16—18 % та відбувається переподрібнення вугільних концентратів, що збільшує вміст фракції 0—0,5 мм, яка негативно впливає на якість коксу.Мета. Розробка науково-обґрунтованих рекомендацій щодо вдосконалення тракту підготовки вугільної шихти до коксування та використовуваного в них необхідного обладнання задля зниження споживання електроенергії та підвищення якості доменного коксу.Матеріали й методи. Використано емпіричні методи досліджень із застосуванням математичного апарату обробки статистичних даних.Результати. Розроблено технологічну схему підготовки вугільної шихти, яка дозволяє підвищити якість доменного коксу та зменшити питомі витрати електроенергії орієнтовно в 48 раз.Висновки. Підвищення якості підготовки вугільної шихти до спікання з одночасним зниженням енерговитрат обладнання, що виконує її переробку, може бути реалізовано удосконаленням існуючих технологічних трактів шляхом організації ділянок попереднього відсіву готового класу перед дробленням.

Purpose. The purpose of this work is to substantiate the optimal values of the belt conveyor parameters, at which the specific energy consumption for the cargo transportation takes on the lowest value. Methodology. The substantiation of the optimal values of the belt conveyor parameters was carried out by minimizing the function of specific energy consumption, which represents the energy consumption for the transportation of a cargo weighing 1 kg at a distance of 1 m. In the course of research, the drive force was determined using the contour bypass meth-od. In this case, the specific loads from the transported cargo, belt and roller supports were presented as functions of the belt width. To establish the optimal values of the conveyor productivity and belt speed, the belt width was presented as a function of these values, taking into account the physical and mechanical properties of the transported cargo, the design features of the roller supports and the belt angle. Findings. I obtained the dependences of specific energy consumption on the design parameters of the conveyor. Their analysis made it possible to identify the opti-mal values of the belt width, conveyor productivity, belt speed, and the optimal ratio of the last two values for dif-ferent types of transported cargo. It is noted that the results obtained can be supplemented by carrying out calcula-tions according to the formula given in this work. It has been established that the optimal value of the belt width depends only on the belt angle and on the coefficients that determine the energy losses, in particular the movement resistance coefficient of the belt; the influence of the specified coefficient increases with an increase in the belt angle. In addition, the optimal value of the belt width does not depend on the conveyor length, its productivity and belt speed. Originality. The dependences of the specific energy consumption on the design parameters of the belt conveyor were obtained, which made it possible to establish the optimal values of the belt width and the ratio of the conveyor productivity to the belt speed. Practical value. The results of this work can be used in the design of energy-efficient belt conveyors, which are characterized by the lowest specific energy consumption for cargo transportation.

In this paper, an attempt is made to optimize the control parameters for the minimization of specific energy consumption in turning GFRP composites using particle swarm optimization (PSO).Optimization of specific energy consumption in machining is helpful to evaluate the process energy characteristics and also facilitates choosing the best control parameters for energy saving. The control parameters considered are cutting speed, feed, depth of cut and fiber orientation angle. Experiments are planned and executed according to Taguchi’s L25 orthogonal array in the design of experiments on an all geared lathe with PCD cutting tool insert. A quadratic predictive model was developed for specific energy consumption using RSM and the optimal combinations of control parameters were determined using PSO. The Predicted results from PSO show that there is an improvement in MRR by 46.44% and a reduction in SEC by 33.69%. From the confirmative experimental results, it is observed that PSO algorithm has a powerful global search ability to solve the optimization problem.

In this paper, the effect of two options (first option: fluidized bed drying (120–160 °C) + sun drying; second option: fluidized bed drying (120–160 °C) + again fluidized bed drying (65 ± 2 °C)) of two-stage drying on kinetics, energy consumption, quality of dried maize as color, nutritional properties, and hardness was evaluated to assess the drying performance. First stage drying for both options was executed by FBD at 7.0 cm bed thickness within the temperature range of 120–160 °C for 1.5–4 min. Then, the samples were tempered for 45 min in a closed container after completion of first stage drying. Second stage drying was then done by sun drying method (temperature: 33–36°C, RH: 52–65%, air velocity 0.4–0.6 m/s) for first option while for second option, it was accomplished again by FBD (65 ± 2°C). Drying time was shorter in the case of second option (2.23 h) than first option (4.98 h). Effective moisture diffusivity was found higher in both options of two-stage drying (10.5 × 10−09 m2/s to 63 × 10−09 m2/s) than control drying. Specific energy consumption was lower in first option compared to second option. Color of dried maize in two-stage options deteriorated markedly. However, nutritional qualities of dried grain for two-stage drying technique were similar to control sample. Hardness of the two-stage dried maize was lesser than control product. The two-stage drying options of maize drying instead of conventional sun drying method can be considered an alternative drying technique for the commercial maize drying industries.

Thailand’s ceramic industry is one of the most important industries in the country in terms of export figures. However, production consumes a large amount of energy and raw materials, which causes ...

The present work aims to improve the understanding of the effect of different drying strategies at varying temperatures on the dynamic drying behaviour and quality of organic products such as carrots using non-invasive measurement techniques. For this purpose, carrot slices of 3 mm thickness were dried under three different strategies namely air temperature controlled (A), product temperature controlled (P) and stepwise temperature controlled (S) at different temperatures (50 °C, 60 °C and 70 °C) to measure and analyse the changes in moisture content, colour, total carotenoid retention, water activity, rehydration ratio and specific energy consumption. From the investigation performed, it was incurred that the application of different drying strategies influences rather significantly both the product quality as well as the overall process efficiency. Modelling the drying curves deemed Page model to be a good fit for all the strategies with R2adj = 0.99 and RMSE = 0.01. The results also show that implementing strategy P not only led to shorter drying times but also led to higher total carotenoid retention within the samples (TCR = 0.59–0.73). Colour changes, however, were observed to be maximum with strategy P as compared to strategy A and strategy S. Furthermore, the use of a non-invasive measurement technique such as infrared camera proved to be reliable in order to detect the phase transition of the product during the drying process.

One of the possible ways to intensify and increase the efficiency of extraction of biologically active substances from plant materials is the use of microwave radiation. This article presents the results of a study of the influence of parameters of the microwave extraction process on the output of flavonoids from the leaves of the littlewale (Lithospermum officinale L.), belonging to the Boraginaceae family. This plant contains isoquercitrin, which is one of the key flavonoids with the property of tissue regeneration. It was shown that the maximum yield of the target components is achieved with a microwave generator power of 100 W and exposure duration of 2.5 min at a field frequency of 2450 MHz (specific energy consumption is 8.4 kWh/kg). This output is comparable with the output when using conventional convection heating. Microwave radiation provides a 16-fold reduction in the duration of extraction of the sum of flavonoids and an increase in the degree of extraction of isoquercitrin by 23%. The action of microwave energy leads to the destruction of plant tissue, which contributes to a more efficient extraction of flavonoids from plant raw materials.

About 40 % of the forest area in the Russian Federation is occupied by larch trees growing in the southern regions of Eastern Siberia and the Far East, where existing and reconstructed woodworking enterprises are located. In this regard, the use of larch wood in the production of fibrous semi-finished products is an urgent task for the Russian forest complex. As is known, larch wood contains a large number of extractive substances that have a significant impact on the process of its deep chemical processing. Therefore, it can be assumed that the production of wood (mechanical) pulp from larch wood, in particular chemical-thermomechanical pulp (CTMP), will be very effective, but with its own specific features. In this paper, it is proposed to modify the technology by using enzymes – protein catalysts of various reactions. The purpose of this study is to determine the potential of using larch wood enzymatic treatment in CTMP-technology, to evaluate the effect of enzymes on the physical and mechanical parameters of the fiber and the specific energy consumption during refining. Industrial samples of Larix sibirica Ledeb (Pinaceae) wood chips were used to obtain CTMP. Five commercially available enzymatic agents were used to treat wood chips. CTMP was obtained using laboratory equipment that simulates the industrial stages of production. Enzymatic treatment of larch wood has shown an improvement in the technological parameters of CTMP production, namely, a decrease in the specific energy consumption for refining and an increase in the quality of finished products.

Bisphenol A (BPA) is a known endocrine disrupter and was detected in surface waters. We investigated the mineralization of BPA by electrochemical oxidation. Six different types of electrodes, including the boron-doped diamond (BDD), platinum (Pt), and mixed metal oxide (MMO) electrodes; RuO2–IrO2, RuO2–TiO2, IrO2–Ta2O5, and Pt–IrO2, were compared as the anode material. Total organic carbon (TOC) was analyzed to monitor the mineralization efficiency of BPA. BDD achieved 100% BPA mineralization efficiency in 180 min and at a current density of 125 mA/cm2, whereas the TOC removal efficiency of Pt was 60.9% and the efficiency of MMO electrodes ranged between 48 and 54%. BDD exhibited much lower specific energy consumption, which corresponds to a lower energy cost (USD63.4 /kg TOC). The effect of operational parameters showed that the BDD anode was much more affected by the current density, initial BPA concentration, and electrolyte concentration than the other parameters such as the stirring speed and interelectrode distance. HIGHLIGHTS BDD, Pt, RuO2–IrO2, RuO2–TiO2, IrO2–Ta2O5, and Pt–IrO2 were compared as the anode material.; BDD performed better than MMO anodes for the mineralization of BPA.; BDD anode showed 100% TOC removal efficiency in 180 min.; Current efficiency of BDD was 2.53 times higher than Pt and 3.7 times than MMOs.; The specific energy consumption was higher for MMO electrodes.

The brick kiln industry is one of the largest and most highly unregulated industrial sectors in developing countries. Most of the kilns use low-quality coal as primary fuel along with small quantities of bagasse, rice husk, and wooden chips. As a result of inefficient methods of combustion in conventional brick kilns, such as fixed chimney Bull’s trench kilns (FCBTKs), harmful pollutants are emitted in high quantities, which ultimately deteriorate the environment and are widely in operation in Pakistan. The most prominent harmful pollutants include carbon dioxide (CO2), carbon monoxide (CO), sulphur dioxide (SO2), black carbon (BC), and particulate matter less than 2.5 microns (PM2.5). Over the years, new technologies have been adopted by developed countries for the reduction of environmental burdens. One of these technologies is induced draught zigzag kilns (IDZKs), or zigzag kilns (ZZKs), technology, which effectively improves the combustion across the path of bricks stacked in a zigzag pattern. For the mass adoption of this technology, environmental assessment and comparison of both technologies is a crucial step. Both types of kiln sites are investigated for the analysis of their emissions and their environmental impact in this work. Carbon mass balance equations are used for the calculation of emission factors. Collected inventory data is then used for the life cycle assessment of both types of kilns using open LCA (version 1.10.3) and the Eco-invent database. According to the study, ZZK technology outperforms FCBTK in all aspects. The analysis of the specific energy consumption (SEC) of fired bricks for each kiln type reveals that ZZKs require 30% less energy than the conventional FCBTK. This implies that ZZKs demand lesser fuel than FCBTKs. The zigzag technology adoption scenario, in particular, can lead to approximately 30% lower CO2 emissions, which can be further reduced by up to 80% when taking into account black carbon (BC) emissions. Additionally, the adoption of zigzag technology can result in a 35% decrease in PM2.5 emissions. The study shows that adopting ZZK technology significantly reduces impact categories, such as particulate matter formation (PMF), photochemical oxidant formation (POF), and terrestrial acidification (TA) by 63%, 93%, and 95%, respectively.

This paper analyzes methods of heating battery-driven electrical buses. The examined buses were two identical airport transport buses and two buses used in local transportation. To heat the first buses, an electrical water heater with a heating capacity of 20 kW, and for air conditioning, a rooftop air conditioner with a cooling capacity of 20.6 kW was installed. Climate control in the city buses was achieved using an R744 heat pump with a cooling capacity of 25 kW and a heating capacity between 14 and 21 kW, along with an electrical water heater with a capacity of 32 kW. During the project, the measurement data of the buses described above were taken for a full year and evaluated. The analysis of the measurement data brought insights into the specific electrical energy consumption of climate control in the buses in real operating conditions at outdoor temperatures between 2 °C and 36 °C. The results of this project additionally provide information on the optimization potential for the climate control of buses.

There are about 68 types of mulberry fruit with a wide ecological production area. Different mulberry species are grown in large fields in Turkey. Mulberries are largely dried-consumed, but sometimes they are used as fruit juice. In this study, black mulberry fruit was collected in two different ripening levels (semi-ripe and full-ripe) and oven-dried at 50, 60 and 70°C drying temperatures. Initial moisture contents of semi-ripe and full-ripe fruits were determined as 86.74% and 82.95%, respectively. Fruits were dried to have final moisture levels of 10-15%. Drying duration, drying models, effective diffusion, activation energy, specific energy consumption, color parameters and chemical properties of dried fruits were examined and the effect of ripening levels and drying temperatures were investigated. In terms of drying duration, while full-ripe fruits dried in a shorter time, effective diffusion, activation energy and specific energy consumption values were found to be higher than semi-ripe fruits. In terms of color parameters, semi-ripe fruits are recommended to be dried at 50 or 60°C drying temperatures and full-ripe fruits should be dried at 50°C drying temperature for better preservation of color parameters. On the other hand, a common proper drying temperature could not be identified for acidity (pH), water soluble dry matter and titratable acidity.

Densifying alfalfa into briquettes is one of the effective ways to increase its density and reduce the cost of storage and transportation. To explore the influence of vibration frequency on alfalfa briquetting, vibration-assisted compression tests with six vibration frequencies of 0, 9.52, 15.56, 21.24, 27.50, and 33.44 Hz were carried out. The results showed that the compression with vibration could reduce the maximum forming pressure and the energy consumption. The quality of alfalfa briquettes was improved compared with the compression without vibration. Within the range of test, when the vibration frequency was 21.24 Hz, the maximum pressure was the minimum, which was 5.83 MPa. In addition, the specific energy consumption was the lowest, which was 1374 J/g/cm3. The experimental results provided a basis for determining the optimum vibration parameters of alfalfa compression.

Lighting systems are used in all building types and consume large amounts of energy as well as adding to carbon dioxide (CO2) emissions. The aim of this research was to analyze energy consumption in the lighting systems of a new building. This study conducted a preliminary energy consumption audit of the Faculty of Science on the Kasetsart University Sriracha Campus, Thailand. The actual energy consumption in the study period and the specific energy index (specific energy consumption) were assessed. The results showed that the total electric power of all bulbs in the building was 72.13 kW and about 74 % were 20 W lamps. Annual energy consumption and carbon dioxide emissions were 157,753.73 kWh and 89,477.92 kg carbon dioxide for 9 hours use. The total energy consumption accounted for 1.64 % and 4.37 % based on 9 and 24 hours operation, respectively. The specific energy index was higher than the average for this university. Therefore, the energy consumption data obtained are very important in developing energy‐saving measures.

Introduction. Currently, in various technology areas, bronze, cast iron and other antifriction metals are replaced by polymer composites, which extend significantly service life of tribocoupling. An advanced antifriction polymer is ultra-high-molecular-weight polyethylene. The study deals with determining the optimal specific energy consumption for the mechanical activation of the polymer dry mixed powders and nanomodifiers in the planetary ball mill Pulverisette 7, which ensure the best complex of physico-mechanical and rheological properties of nanocomposites. Materials and Methods. In this work, we used GUR 4120 Ticona ultra-high-molecular-weight polyethylene with a molecular weight of 5 million, a Tuball Matrix Beta concentrate of activated carbon nanotubes at a concentration of 0.1%, calculated with reference to carbon nanotubes, and hydrophobic nanocrystalline silicon dioxide with a dispersion of 20 nm at the same concentration. Mechanical co-activation of polymer powders and nanomodifiers, when varying the specific energy consumption, was carried out in the planetary ball mill Pulverisette 7. The production of films from powders, for studying the elastic-strength and rheological characteristics of nanocomposites, was carried out with the use of the hydraulic press Gibitre. Tests were carried out respectively on the tensile testing machine UAI-7000 M and the rheometer Haake MARS III. Results. It has been established that the best physico-mechanical and rheological properties of nanocomposites are with specific energy consumption for mechanical activation of 3,000‒3,200 J/g that allows us to consider them optimal. The mechanical activation of ultra-high molecular weight polyethylene powder, reducing slightly the elasticity modulus and tensile strength of thermally pressed samples, does not affect the dynamic viscosity of melts at an energy consumption of 650‒4,550 J/g. Discussion and Conclusion. The use of carbon nanotubes and nanocrystalline silicon dioxide at a concentration of 0.1% can significantly improve the physical-mechanical and rheological properties of the polymer with energy costs of 3,000‒3,200 J/g for mechanical activation in planetary ball mills. Nanocrystalline silicon dioxide is a more effective modifier that can be explained by its better dispersion in the polymer matrix due to the lower tendency of nanoparticles to agglomerate.

The subject of the research is the process of functioning of disk working bodies and a ploughshare of the soil-cultivating loosening-separating installation, which carries out lifting and separation of the soil. When moving the ploughshare at shallow depths (0.03 ... 0.12 m), the movement of the soil along it is complicated by the formation of a soil roll, which is formed in front of the ploughshare. The soil is loosened and scattered to the sides, not providing the necessary support required to move it to the loosening-separating device. Passive rotating disks are installed on both sides of the ploughshare so that the soil does not clump and scatter to the sides. The object of the study are the disk elements of the lifting and trimming device, which can significantly increase the efficiency of the technological process of soil movement on the ploughshare while reducing the specific energy consumption of the process. The initial information to substantiate the study was obtained by analyzing the literature. It is determined that increasing the radius of parallel freely rotating flat disks from 0.175 to 0.270 m leads to an increase in the thickness of the soil layer on the ploughshare by no more than 17%. With increasing kinematic parameter of rotation of the disks from 0 to 0.6 soil compaction on the ploughshare decreases by 2.73 times, from 0.6 to 1.0 - by 1.25 times and from 1.0 to 1.2 - by 1, 04 times. It is established that increasing the angle of the ploughshare initially leads to a decrease in the soil level on it and reaches a minimum at an angle close to 25 °. With a further increase in the angle, the soil level on the ploughshare increases. It has been experimentally proved that the greatest influence on the limiting distance between the disks at which the lifting of the soil layer by the ploughshare is carried out without jamming is the soil moisture. The relevance lies in the fact that the simultaneous use of passive disk working bodies together with a ploughshare allows to improve the methods of pre-sowing tillage to improve its agronomic qualities.

The aim of this study investigated the effects of some various variables on drying a thin layer of pomegranate peels exposed to infrared and hot air. Three different levels of infrared power, namely: 150, 200 and 250 W and three different exposure distance "the distance between infrared heater and samples" of dying are 10, 15 and 20 cm with air temperature 40 oC and air velocity 1.5 m/s were studied. Moisture ratio and drying time affected by infrared power and exposure distance, compatibility of experimental data to some drying models, effective diffusivity "Deff", Specific energy consumption "SEC "and rehydration were also studied. The results show that the higher the infrared power and the lower exposure distance the lower the moisture ratio and the total drying time reduced, and it was found that the least drying time was 30 minutes with infrared power 250 W and exposure distance 10cm. Lewis model was best fitness to the experimental data with average R2 0.9972. The maximum values of Deff were recorded at highest infrared power 250 W. The rehydration ratios ranged between 0.80 to 2.42 under various dryin conditions.

La presente investigación se desarrolló en las instalaciones del Centro de Investigaciones del Níquel ¨Capitán Alberto Fernández Montes de Oca¨, teniendo como objetivo evaluar el efecto que tiene la sustitución del petróleo aditivo por el carbón bituminoso en el proceso de molienda de las lateritas. En ella se demostró que el índice de Bond se incrementa a medida que aumenta el contenido de carbón bituminoso en la mezcla. Al compararla con la mezcla de petróleo y laterita utilizada en la industria se puede afirmar que utilizando un porcentaje inferior a 4,5 % de carbón bituminoso no se incrementa el consumo energético específico en los molinos, mientras que al utilizar el carbón bituminoso en el rango de 5,0 a 5,5 % se incrementa en 3,0 kW-h/t. Las mezclas preparadas cumplieron con las especificaciones exigidas por el ensayo de Bond, presentando un comportamiento granulométrico con predominio de las partículas gruesas, antes y después de ser sometidas a dicho procedimiento.

The present old standard efficiency motors (SEM) in black tea processing machinery consume large amount of electricity, thus increases the cost of production. Technologically improved high-efficiency motors (HEM) or HEM coupled with variable speed drive (VSD) could be useful to achieve high-energy efficiency. Therefore, a study was conducted with the focus to determine the feasibility of introducing HEM and VSD in withering and rolling machinery of black tea manufacturing. A withering trough and two different capacity rotorvane rollers were selected for the study, and the energy consumption of different treatments was measured, and specific energy consumption, annual bill savings, simple payback period, and potential carbon dioxide emission reduction were calculated. The results showed that introducing HEM or HEM coupled with VSD saves the energy compared to SEM (p

The present work deals mainly with dehydration characteristics of onion slices. Microwave power levels of 100, 350, 550 and 750 W was practiced to dry onion slices with thicknesses of 2.5, 5, 7.5 and 10 mm. The results showed that moisture diffusivity and specific energy consumption of the process increased with both increasing microwave power and the samples thickness, and ranged from 0.82 × 10−8 to 6.13 × 10−8 m2 s−1 and from 0.82 to 5.43 MJ kg−1 water, respectively. The average activation energy varied in the range of 1.28–1.77. Furthermore, for simulation of drying process and to predict the moisture removal behavior of the samples, multi-layer feed-forward (MLF) artificial neural network (ANN) was employed. Practicing different networks and based on statistical parameters, the best topology, transfer functions and training algorithms were determined. The results revealed that, as a powerful tool, ANN modeling could be effectively used to predict drying kinetics and determine the moisture content of the samples.

The rheological properties of the compression process of sweet sorghum straw were studied. The selected experimental factors comprised of the compression density, cutting length, compression speed, and moisture content, and specific energy consumption were selected as the evaluation index of the compression characteristics. The Box-Behnken test scheme was used to analyze the response surface test. The results showed that the selected compression model and specific energy consumption model of the sweet sorghum straw compression process were obtained. The primary factors contributing to energy consumption were the cutting length, moisture content, and compression density. The optimal parameters were as follows: a compression density of 500 kg/m3, a cutting length of 20 mm to 30 mm, a moisture content of 60.06%, and a specific energy consumption of 66 kJ/kg. The results provided methods for reducing the total energy consumption of the compression process and a theoretical basis for the compression and bundling of sweet sorghum.

The concepts of total and specific energy consumption in the construction of large-panel buildings are reviewed. Taking into account the volumetric planning, structural, organizational, technological and material and technical aspects of construction, a general algorithm for calculating the total and specific energy consumption at the construction site during the construction of large-panel buildings was formed and the values of the total and specific energy consumption for the representative object were calculated.

For solving the problems of long time and serious nutrient loss in the natural air thawing process, a new vacuum thawing method based on the principle of vacuum sublimation and rehydration thawing (VSRT) was proposed. Frozen pork with an initial temperature of -18 °C and a mass of 3 kg was selected as the research object. The sublimation time as a key parameter of VSRT was set as 10, 20, or 30 minutes, and the corresponding changes of thawing rate, texture parameters of pork, thawing loss and specific energy consumption were analyzed. The results showed that the overall thawing rate of VSRT was significantly higher than that of the natural air thawing (NAT) method. When the sublimation time was 20 minutes, the thawing rate was fastest and increased by 77% compared to NAT, the texture parameters of thawed pork were not significantly different from that of raw pork, the thawing loss was relatively less, and the specific energy consumption was lower than that of the microwave thawing method. The mechanism of the thawing process was discussed by illustrating the pressure in the vacuum chamber and core temperature of frozen pork.

The cutting performance of the boom-type roadheader impacts the energy consumption and efficiency of coal mine roadway excavation. The purpose of this work is to investigate the influence of motion parameters on cutting performance. The motion of the cutting head during swing cutting was simplified to establish a numerical model. Rock samples were arranged to perform the swing cutting to test the validity of the numerical model based on the coal-rock cutting platform. The cutting specific energy consumption and the average cutting force on picks involved in cutting were used as indexes to evaluate the effects of the cutting depth, velocity, and subsequent cutting distance on cutting performance. The mechanism of the cutting head was also explained. The results show that the cutting performance is optimal when the cutting depth is 1/2 to 2/3 of the cutting head length. In terms of energy consumption, cutting performance is more sensitive to cutting depth than to cutting velocities. The cutting performance indexes tend to be stable until the subsequent cutting distance exceeds the diameter of the cutting head.

The multistage drying system is one of the novel methods that has small specific energy consumption (SEC) compared to the conventional single drying systems. Rotary and fluidized bed dryers are the...

A new modified two-module electric modular-pouring furnace with an upper heating system of heaters and an additional “zero” (non-electrified) module is considered. By eliminating the lower third firing module, a reduction of energy consumption by a third compared to the three-module prototype furnace was achieved. Suspended emitting elements, which are not only energetically more efficient than the previous ones made of strip heaters, but also constructively provide double the furnace throughput due to the suspension under thermal covers, are used in the modules. This leads to a doubling of its performance. Altogether, it gives a decrease in the specific energy consumption of vermiculite firing in a new two-module furnace to a level of 50.4 J/m3.

Industrial-scale testing was performed for fine screen reject recovery technology with a mixed office waste (MOW) pulping line. Results showed that the recovery system removed macrostickies and dirt specks with an efficiency of 95.7% to 98.3% and 51.5% to 76.8%, respectively. These results were not affected by the running consistency (0.26% to 1.44%). The recovery system improved the physical strength of the pulp. Relative to untreated rejects, the tensile index increased 5.1% to 15.2%, the tear index increased 6.6% to 11.4%, and the breaking index increased 6.6% to 25.7%. Running consistency had no obvious effects on tensile strength and tear strength, but bursting strength increased with increasing running consistency (%). The volume energy consumption (y) increased with increasing running consistency (x), and a linear relationship of y = 0.73x + 4.2191 (R² = 0.9466) was observed. The specific energy consumption (y) of the pulp decreased with increasing running consistency (x), and the relationship could be expressed as y = 499.67x-0.906 (R² = 0.9959).

A comparative approach was carried out between artificial neural networks (ANNs) and response surface methodology (RSM) to optimize the drying parameters during infrared–con- vective drying of white mulberry. The drying experiments were performed at different air temperatures (40°C, 55°C, and 70°C), air velocities (0.4, 1, and 1.6 m/s), and three levels of infrared radiation power (500, 1000, and 1500 W). RSM focuses on the maximization of effective moisture diffusivity (D eff ) and minimi- zation of specific energy consumption (SEC) in the drying pro- cess. The optimized conditions were encountered for the air temperature of 70°C, the air velocity of 0.4 m/s, and the infrared power level of 1464.57 W. The optimum values of D eff and SEC were 1.77 × 10 −9 m 2 /s and 166.554 MJ/kg, respectively, with the desirability of 0.9670. Based on the statistical indices, the results showed that the feed and cascade-forward back-Propagation neural systems with application of Levenberg-Marquardt train- ing algorithm and topologies of 3–20-20-1 and 3–10-10-1 were the best neural models to predict D eff and SEC, respectively. This finding suggests that the ANN as an intelligent method with better performance compared to the RSM can be used to pre- dict the drying parameters of the infrared-convective drying of white mulberry fruit. info:eu-repo/semantics/publishedVersion

Heating and vaporization of quartz particles in argon-plasma flow of an RF inductively coupled plasma torch is numerically simulated using a model of two-phase collisionless monodispersed mixture. Conditions for flow regimes with the ring-type frontal vortex and complete or partial penetration of particles to the high-temperature region of discharge are determined. Dependences of the degree of vaporization and specific vaporization energy on the main working parameters of RF-ICP torch and dispersed particle flow (primarily, feed rate of quartz particles, coupled power, and size and injection angle of particles in the plasma flow) are determined. Recommendations on the optimal parameters of the inductively coupled plasma torch quartz particle flow are presented. It is shown that an RF inductively coupled plasma torch with a power of about 5 kW provides complete vaporization of quartz particle flow with sizes of 50–70 μm and a feed rate of (8–10) × 10–5 kg/s at a specific energy consumption of about 50 MJ/kg

The article proposes a block diagram of the process of drying bulk plant materials in a spiral dryer, which covers a set of parameters that determine the drying result. To carry out energy-efficient high-quality drying of bulk agricultural materials and control the drying process in a dryer with spiral perforated surfaces, it is necessary to find such parameters of the dryer and drying agent that provide minimal heat and electricity consumption the required performance of the spiral dryer and the initial parameters of the bulk agricultural material. To assess the energy efficiency of the design of the spiral dryer, the specific energy consumption is set: for the drive of the drying chamber and the loading auger; on the formation of the drying agent; to inject the formed drying agent into the drying chamber and pass it through the entire volume of material at a given speed; for the operation of loading and unloading devices with the required bandwidth, the type of which may vary depending on the scheme of organization of the technological process. The presence of several spiral perforated surfaces allows reducing the height of the layers of bulk material on the turns of the perforated surfaces and leads to an increase in the contact area of ​​the drying agent with the material. Due to this, uniform drying of the bulk agricultural material and efficient use of the energy potential of the drying agent is achieved.

The main aim of this paper is to accelerate the drying process of black ginger in a forced convection mixed mode horizontal solar dryer (FCMHSD) by using two successive air mass flow rates. When the drying rate attains the falling rate period, air mass flow rate has minimal effect on drying rate. To diffuse bound moisture present in the product, air mass flow rate has to be reduced for raising the air temperature in the solar dryer. In this manuscript, two cases were considered for drying; Case – 1 with constant air mass flow rate of 0.062 kg/s and Case – 2 with two successive air mass flow rates of 0.062 kg/s during the initial period of drying and 0.018 kg/s during the falling rate period. The performance of FCMHSD was evaluated in terms of drying time, drying efficiency, specific energy consumption (SEC) and moisture diffusivity. The estimated SECs for Case – 1 and Case – 2 were 1.07 kWh/kg and 0.56 kWh/kg, respectively. A significant improvement in thermal performance and moisture diffusivity were observed when the FCMHSD operated under Case – 2 than under Case – 1. The use of two successive air mass flow rate is a new approach for accelerating the drying process.

The present work is focused at the study and experimental confirmation of the possibility for increasing the efficiency of an electric modular descending furnace in terms of reducing the specific energy consumption of roasting vermiculite concentrates by obtaining the most rational structural furnace design. Research methods were based on a theoretical analysis of the working process energy characteristics for the furnace unit, such as performance factor and specific energy consumption, the laws of thermal radiation physics and thermal engineering, as well as on the analysis of experimental data obtained during testing of the experimental furnace model under laboratory conditions at a temperature of 730-780oС and an annealing time of 2.48-3.06 s. Due to changes in the structure of the six-module furnace, the specific vermiculite roasting energy consumption was reduced to 188.9 and 197.0 mJ/m3 in accordance to calculated and experimental data, respectively. As compared to the minimum value for a standard similar furnace, the decrease in the specific energy consumption for the modernised furnace amounted to 17.9%. The effect of reducing energy consumption was shown to be due to the structural transformation of the furnace unit by transferring the lower module with a lowest performance factor and installing it in parallel with the upper module, leading to a significant increase in the overall efficiency of the furnace. Additional efficiencies were obtained by applying suspended heating systems to the furnace under consideration. According to calculations and experimental studies, due to the furnace unit structural transformation and the use of more energy-efficient suspended heating systems in the furnace energy blocks, the expected combined effect of reducing the specific energy consumption in roasting vermiculite concentrates averaged up to 147.3 mJ/m3 for various types and size groups of furnaces.

To investigate the matching rules of cutters with different blade widths in hard rock and extremely hard rock environments, this study carries out a full-scale cutting test of 432-mm disc cutters with blade widths of 12 mm, 19 mm and 30 mm. A multifunctional cutter performance experimental system was used to test the cutting loads and rock-breaking quantity of rust stone granite (hereinafter referred to as hard rock) and granite (hereinafter referred to as extremely hard rock) as well as to analyse the specific energy consumption for rock breaking under different cutting parameters. The experimental results show that (1) the blade width has a greater influence on the normal force than on the rolling force. The rock-breaking resistance of the 12-mm-blade-width cutters under extremely hard rock conditions is 36.7% lower than that of conventional cutters. (2) Under the same conditions, the smaller the blade width is, the smaller the specific rock-breaking energy consumption is and the smaller the optimal cutter spacing is. Under extremely hard rock condition, the specific energy consumption of the 12-mm-blade-width cutters is 37.9% lower than that of conventional cutters. (3) With a certain gross thrust of a single cutter, the rock-breaking quantity of a single 12-mm-blade-width cutter is much larger than that of the 19-mm-blade-width cutter, regardless of the types of rock. Under extremely hard rock conditions, the S/P of the 12-mm-blade-width cutter with the highest rock-breaking efficiency is approximately 10–12.