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Capacitive deionization (CDI) is a promising and cost-effective technology that is currently being widely explored for removing dissolved ions from saline water. This research developed materials based on activated carbon (AC) materials modified with zinc oxide (ZnO) nanorods and used them as high-performance CDI electrodes for water desalination. The as-prepared electrodes were characterized by cyclic voltammetry, and their physical properties were studied through SEM and XRD. ZnO-coated AC electrodes revealed a better specific absorption capacity (SAC) and an average salt adsorption rate (ASAR) compared to pristine AC, specifically with values of 123.66 mg/g and 5.06 mg/g/min, respectively. The desalination process was conducted using a 0.4 M sodium chloride (NaCl) solution with flow rates from 45 mL/min to 105 mL/min under an applied potential of 1.2 V. Furthermore, the energy efficiency of the desalination process, the specific energy consumption (SEC), and the maximum and minimum of the effluent solution concentration were quantified using thermodynamic energy efficiency (TEE). Finally, this work suggested that AC/ZnO material has the potential to be utilized as a CDI electrode for the desalination of saline water. [ABSTRACT FROM AUTHOR]

The development of an electric vehicle harvester for aquatic vegetation is a technical challenge for researchers due to specific requirements: high-torque operation at low travel speeds, high maneuverability, high load capacity, low draught, and affordable price. The collective of authors proposed an electro-hydraulic architecture based on paddles driven by hydraulic motors for propulsion and auxiliary services also driven by motors and hydraulic actuators. The proposed energy source for the aquatic harvester is electric batteries, it was developed a system of 33 kWh Li-Ion batteries connected in parallel, which power an electronic converter and a 14.5 kW rated power electric motor that drives a hydraulic double-circuit pump. The vehicle can be controlled remotely. The paper presents the prototype made and the results obtained during laboratory tests performed for the electric powering system. [ABSTRACT FROM AUTHOR]

Due to the great differences in mechanical properties between hard concretion and coal, the shearer drum cutting coal and rock containing hard concretion will inevitably lead to a series of problems, such as severe load impact, increased cutting specific energy consumption and low coal loading efficiency. Taking the cutting part of a thin coal seam shearer in service in the target mining area as the prototype, the mechanical models of shearer drum and rocker arm are established by using UG, and the discrete element model of coal wall with hard concretions is built by importing it into EDEM. The influence law of traction speed on coal loading rate, drum load and cutting specific energy consumption is analyzed, and the corresponding fitting relationship function is obtained. Taking the traction speed as the design variable, and the drum load, cutting specific energy consumption and coal loading rate as the comprehensive indicators, a multi-objective optimization function is established. The optimal solution is obtained by using NSGA II optimization algorithm, and the accuracy of the simulation is verified by experiments. This method has certain engineering significance for the reasonable selection of shearer traction speed. [ABSTRACT FROM AUTHOR]

In order to analyze the impact angle of pick cutter, the angle of alloy head and the cutting line spacing on rock breaking effect, the three-dimensional model of rock cutting by pick cutter was established by solidworks, and the three-dimensional finite element model of rock breaking by pick cutter based on penetration failure and compression damage was established by using dynamic simulation software ANSYS/LS-DYNA. For the drum with a diameter of 1200 mm, a length of 900 mm and a rotational speed of 30 rot/min, when the impact angles of the picks are 30°, 37°, 45° and 52°, the angles of the alloy heads are 70°, 80°, 90° and 100°, and the intercept distances are 250 mm, 275 mm, 300 mm and 325 mm, the rock breaking simulation based on the finite element analysis software is carried out, and the load and specific energy consumption of the drum are obtained. Finally, through the analysis and comparison, the existing parameters are optimized, and a better parameter model is obtained. [ABSTRACT FROM AUTHOR]

In this paper, the arrangement of picks on the cutting head of the transverse-axis driving anchor machine is analyzed and discussed, and two kinds of arrangement modes, namely sequential arrangement and punnett arrangement are studied. Based on the explicit dynamic analysis program ANSYS / LS-DYNA and the Holmquist-Johnson-Cook model, the contact mechanics characteristics between the pick and the rock are analyzed by using the theory and processing method of contact dynamics, rock mechanics and finite element. The maximum cutting force, average cutting force, cutting specific energy consumption and cutting force variance are obtained. By comparing the two groups of arrangement, it is concluded that the punnett arrangement is better than the sequential arrangement. Using MATLAB software to calculate the spectrum of cutting force, it is concluded that the main frequency is between 0 ~ 10Hz when the cutting head works. [ABSTRACT FROM AUTHOR]

Reverse Osmosis (RO) system has become the most practiced technique in the last six decades to desalinate brine and make saline water safe to drink. This paper presents an experimental and modelled set-up of an RO pilot system to monitor the impact of feed water pressure on various thermodynamics parameters of borehole water collected from Ain El Atti, Errachidia, Morocco. The initial testing to check the quality of water confirmed the presence of a high number of dissolved salts in borehole water. The experimental set-up was being installed at the LPHE-modelling and simulations laboratory at the Faculty of Sciences, Mohammed V University, Rabat, Morocco. The study deals with monitoring the impact of feed water pressure on parameters of permeate including salinity (TDS), flow rate (Q), Specific Energy Consumption (SEC), recovery rate (Y) and Retention Rate (TR). The results showed some mixed impact of feed pressure on all parameters ranging from linear positive to linear negative relation. Furthermore, the results also showed that the simulation model showed high validity of the results with experimental results, which showed the accuracy of model. [ABSTRACT FROM AUTHOR]

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The use of waste incineration with energy recovery is a matured waste-to-energy (WtE) technology. Waste incineration can reduce the volume and mass of municipal solid waste significantly. However, the generation of high volumes of polluting flue gases is one of the major drawbacks of this technology. Acidic gases are constituents in the flue gas stream which are deemed detrimental to the environment. The wet flue gas desulphurization (FGD) method is widely employed to clean acidic gases from flue gas streams, due to its high efficiency. A major setback of the wet FGD technology is the production of wastewater, which must be treated before reuse or release into the environment. Treating the wastewater from the wet FGD presents challenges owing to the high level of contamination of heavy metals and other constituents. Membrane distillation (MD) offers several advantages in this regard, owing to the capture of low-grade heat to drive the process. In this study the wet FGD method is adopted for use in a proposed waste incineration plant located in Ghana. Through a mass and energy flow analysis it was found that MD was well matched to treat the 20 m3/h of wastewater generated during operation. Thermal performance of the MD system was assessed together with two parametric studies. The thermal efficiency, gained output ratio, and specific energy consumption for the optimized MD system simulated was found to be 64.9%, 2.34 and 966 kWh/m3, respectively, with a total thermal energy demand of 978.6 kW. [ABSTRACT FROM AUTHOR]

The design and choice of pipe fittings in such systems plays an important role as far as headloss and flow separation are factors of concern. This study aims to investigate the flow of coal water suspension through a converging section, diverging section and a bend using computational fluid dynamics approach. The modelling and simulation are carried out on geometries consisting of both converging and diverging sections of variable angles along with a bend of R/d ratio of 2. The computational fluid dynamics simulation results are in good agreement with the experimental data, with an average percentage error of 1.96%. 1° angle of divergence and 7° angle of convergence are optimum designs for the lowest local headloss. However, the headloss across the entire test section is found to be minimum for the case where the angle of convergence/divergence is fixed at 1° each. The specific energy consumption gives a practical idea about the minimum energy required for the transportation of solids through some distance, which is an all-time minimum for the suspension containing 60% solids by mass. The study presents a detailed investigation into the local as well as global flow characteristics of the coal water suspension through a test section. [Display omitted] • The 7° converging section has the lowest headloss. • The headloss across the diverging section is minimum at an angle of 1°. • The global headloss is minimum for the 1° geometries. • The SEC is minimum for the suspension having solids' concentration of 60% by mass. [ABSTRACT FROM AUTHOR]

Slurry flow (water–glass beads) through a horizontal pipe of diameter, 0.0549 m and length, 3.8 m with two particle sizes, i.e., 125- and 440-micron, has been numerically modeled and investigated based on the kinetic theory of slurry transportation. The effect of particles interaction on the pipe flow characteristics such as velocity profile, wall shear stress, vector regime, granular pressure and temperature has been evaluated at different solid concentration and flow velocity range. It is well established that the pressure drop is the key parameter for the design of efficient slurry pipeline system, which is influenced by factors such as flow velocity, slurry viscosity, solid concentration, pipe material and pipe geometry. However, to best of our knowledge, the estimation of pressure drop at different pipe roughness height and a concentration range of 40–60% is not yet established. Therefore, in the present work, the numerical simulation is carried out for slurry flow through a horizontal pipeline at different roughness heights (Rh = 10–50 micron) and Prandtl numbers, i.e., 1.34, 2.14, 3.42 and 5.83. The kinetic parameters are calculated at a flow velocity (Vm) of 1–5 ms−1 and solid concentration (Cw) range of 40–60%. The results and procedure of the current simulation are validated against the available experimental results in the literature. The outcomes of the present work reveals that pressure drop increases with increase in pipe roughness height for the chosen velocity and solid concentration range. In addition, the larger particle is found to have more influence on the pressure, velocity, temperature distribution for the entire range of flow velocity and solid concentration. Furthermore, settling velocity and specific energy consumption are also predicted and discussed through the slurry pipeline. The findings show that the settling velocity of particle increases with increase in particle size at different Prandtl number. The energy efficiency for solid transportation through pipeline at different Prandtl numbers and particle size are also evaluated. Based on the results, it is concluded that specific energy efficiency varies with solid concentration and particle size, i.e., higher concentration and larger particle size demonstrates higher energy consumption. Furthermore, fluid at low Prandtl number exhibits higher energy consumptions. In order to design the efficient slurry pipeline system, it is recommended that the slurry must be transported at low velocity and high Prandtl number. [ABSTRACT FROM AUTHOR]

Objective. The aim of the study is to find rational ways to change the total energy consumption spent on cement production in terms of 1 m3 of concrete.Method. To obtain reliable data, experimental and laboratory methods for testing cement were used.Result. Tests have shown that at constant concrete strength, the consumption of cement per 1 m3 of concrete decreases with an increase in the specific surface of the binder, especially significantly in the case of Portland slag cement. The calculation results show that with an increase in the specific surface area of cements, the total energy consumption for their production, referred to 1 m3 of concrete of the same strength, decreases, and most significantly with an increase in the specific surface area of cements from 300 to 400 m2 /kg and less from 400 to 500 m2 /kg.Conclusion. To reduce the energy intensity of concrete, it is necessary to use cements ground much thinner than they are ground at cement plants in open-type mills, despite the increase in energy consumption. Cements with high fineness of grinding can reduce the cycle of heat and moisture treatment of concrete products. Reducing the cycle allows to increase the turnover of molds and labor productivity at precast concrete plants, as well as further reduce energy consumption for the production of prefabricated reinforced concrete structures.

The soybean (Glycine max) is used as one of the main protein sources in various animal fodders. However, the presence of anti-nutrients significantly reduces the nutritional value of the bean. To solve this problem, the present work is devoted to the inactivation of the anti-nutrients in soybeans by the use of micronisation as a means of thermal treatment. The purpose of the work is to improve the process of soybean micronisation by determining the impact of the process parameters on the soybean's quality and energy performance, namely - the urease activity and specific energy consumption. A multifactor experiment was carried out using an experimental device for the heat treatment of the beans. The influence of the temperature and time of the heat treatment on the level of inactivation of anti-nutrients and the specific energy consumption for beans with different sizes were established. The modes of heat treatment which allow the inactivation of the anti-nutrients in the soybeans to admissible standard values were also defined. The obtained and studied functional dependencies of the quality and energy indices on the technological factors of the soybean micronisation allow one to improve this process and technical means for its implementation in reducing the anti-nutrient content.

Introduction. The determination of the optimal technological efficiency of the peeling process, in terms of the number of detached casings and unit costs of the process, is an important task. The purpose of the study is to give reasons for a comprehensive evaluation criterion of the technological efficiency of peeling wheat grain and choose the optimal values of the parameters of grain peeling, taking into account the energy intensity of the process. Materials and Methods. To quantify the technological efficiency of peeling wheat grain, we used the following local efficiency criteria: the relative yield of peeling by-products, the relative decrease in grain ash content, the increase in the number of cracked grains, and a comprehensive criterion of efficiency taking into account local criteria and the specific power consumption. Results. The experiments have shown that the technological feasibility of the peeling process is ensured at the percentage of the flap opening at the outlet of the machine 60‒70%. In this case, the relative yield of waste husk is 3.2‒2.8%, the relative decrease in grain ash content is 0.32‒0.20%, and the increase in the number of cracked grains does not exceed 0.85%. With increasing the degree of the flap opening at the outlet of the machine from 50 to 100%, the specific power consumption decreases from 8.7 to 3.5 kW∙h/t. Discussion and Сonclusion. To assess the technological efficiency of wheat grain peeling a generalized efficiency criterion, which includes local criteria, is proposed. It has been experimentally proved their dependence on the intensity of grain processing in the machine. The optimum combination of the flap opening degree at the outlet of the machine at 67% (productivity 0.7 t/h) and the specific power consumption of 5.8 kW∙h/t was defined. In this case, the efficiency complex criterion, taking into account the process energy intensity of, is 4.5 kg/kW∙h.

The plastic injection molding process is essential for rapidly producing intricate plastic parts, yet optimizing its energy efficiency without compromising quality remains a challenge. This paper uses the Plackett-Burman method to investigate parameter interactions and identify optimal settings to minimize energy consumption while maintaining quality with the 750-ton hydraulic injection molding machine. Analysis of variance statistically evaluates parameter impacts. Specific energy consumption and cycle time are chosen as response variables, with eight parameters as factors. Results show screw rotation speed significantly impacts Specific energy consumption (84.18%) and mold closing movement affects cycle time (29.27%). The model explains 94.2% of Specific energy consumption variability and 99.34% of cycle time variability. Specifically, the study found that with an optimal configuration of the parameters, the system achieves an average specific energy consumption of 21.7477 kWh/kg and an average cycle time of 38.174 s. Pareto analysis highlights key factors for optimization, guiding efforts to improve energy efficiency. Interaction analysis reveals factors are largely independent. The prediction profiler offers insights into achieving lower energy consumption and cycle time, aiding cost reduction and process optimization. This study provides valuable insights for enhancing efficiency and sustainability in plastic injection molding. It introduces the novel application of the Plackett-Burman design to optimize energy efficiency in plastic injection molding. These crucial insights address complexity in industrial plastics manufacturing, focusing on key factors impacting energy and cycle time. [ABSTRACT FROM AUTHOR]

Humidification Dehumidification (HDH) desalination is a convenient process to produce drinking water from low temperature saline water in waterfront areas. High energy consumption of the system remains as a limiting factor, besides many enhancements done in improving the system performance. Though HDH system cycles are classified on the basis of air and water cycles, detailed performance analysis of different HDH cycles is absent till date. The present study aims at carrying out parametric analysis of possible HDH layouts and finally proposing a layout with high Gain Output Ratio (GOR) and Recovery Ratio (RR) at the low equipment volumes. Simulations are carried out using the Scilab® software. Simulation results are validated using the experimental data obtained from a pilot plant of open-air open-water single stage system. Variation of system parameters like humidifier volume, dehumidifier volume, GOR and RR were analysed in detail for each individual layouts. Out of the eight different layouts investigated, Layout 8 is found to be the best based on GOR, RR, equipment volume and specific energy consumption. Hence it is recommended to use Layout 8 with an inlet temperature of 74 °C and MFR of 2.4 for productivity of 90 LPH. [Display omitted] • Detailed study on the performance analysis of 8 different layouts are carried out for a fixed productivity. • Optimal feedwater temperature in humidifier of layouts are directly related with the GOR and RR of the system. • Least equipment volume and highest RR is obtained at the highest feedwater temperature, independent of type of layout. • Highest GOR is obtained at the least feed water temperature if air or water or both streams operate in closed cycle. • Layout 8 is found to have the highest GOR and RR at the lowest value of specific energy consumption. [ABSTRACT FROM AUTHOR]

Techno-economic viability is crucial for advancing electrochemical membrane technology (EMT), yet many EMTs remain at low Technology Readiness Levels, hindering comprehensive assessments. This review addresses this gap by analyzing the cost and energy requirement of EMTs in comparison to conventional membrane technologies for water treatment. The EMTs analyzed include Electrodialysis (ED), Reverse Electrodialysis (RED), Electrodialysis Reversal (EDR), Electrochemical Membrane Filtration (EMF), Bioelectrochemical Membrane Systems (BEMSs), Electrochemical Membrane Oxidation/Reduction (EMO/R), Electro-Forward Osmosis (EFO), and Electrothermal Membrane Distillation (Joule heating MD). The review utilizes key performance indicators such as specific energy consumption (SEC) and cost considerations (capital and operating costs), alongside environmental benefits, covering pilot- and industrial-scale demonstrations and existing studies on EMT applications in water purification. The analysis reveals that the SEC for EMTs varies significantly, from 0.01 to 5 kWh/m³, with pilot-scale CNT membrane systems showing notable energy efficiency. Costs for ED range from $0.25 to $1.20/m³, with potential reductions of 30% when integrating ED with RED. BEMS capital costs increase from Microbial Fuel Cells to Microbial Electrolysis Cells and Microbial Desalination Cells. Wastewater treatment using EMTs costs under $0.50/m³, with SEC as low as 0.005 kWh/m³ depending on feed type. EFO may be costlier than traditional FO due to higher energy use but offers potential savings in membrane area and water flux. EMF is cost-effective with low-cost materials, and Joule heating MD shows lower specific heating energy, which may translate to lower cost of water production. These insights are crucial for stakeholders, potentially accelerating the commercial-scale adoption of EMTs. [Display omitted] • SECs of EMTs vary widely (0.01–5 kWh/m3) but pilot-scale CNT membrane-system show significant energy efficiency. • ED cost ranges from 0.25 to 1.2 $/m3, with a potential 30 % energy reduction in ED-RED. • The capital costs of BEMSs increase in the order of MFC < MEC < MDC. • Wastewater treatment using EMTs costs below 0.5 $/m3 with as low as 0.005 kWh/m3, depending on feed. • Newer membrane materials face issues of toxicity and membrane stability. [ABSTRACT FROM AUTHOR]

The emergence of the forward osmosis (FO)-reverse osmosis (RO) hybrid offers simultaneous water reuse and desalination by incorporating FO for wastewater (WW) recovery to dilute seawater (SW) before undergoing RO treatment. The potential of osmotic dilution within the FO-RO hybrid promises elevated FO recovery rates and decreased specific energy consumption (SEC) of RO. Yet, pushing the system to its limits remained unexplored. Employing MATLAB® for simulations across various feed-to-draw volume ratios and diverse WW salinities, the study explored the feasibility of achieving enhanced FO recovery from WW. The study extended to evaluating the adaptability of existing desalination plants to process diluted SW using LewaPlus® design software. The FO simulation confirmed the feasibility of achieving 90 % WW recovery across various operational conditions in many instances. Yet, the optimal configuration for achieving both 90 % WW recovery and RO SEC below 1 kWh/m3 was specific: an 80:20 feed-to-draw volume ratio with an initial WW salinity of 0.5 g/l in FO. This resulted in reduced SW salinity (7.4 g/l), enabling RO desalination at 0.96 kWh/m3, showcasing potential retrofitting applications for existing desalination plants based on software design response. In the comparative study to determine the optimal approach for integrated water reuse and desalination between FO-RO hybrid and independent schemes, the energy efficiency of RO in independent schemes appears favorable, but FO-RO hybrid system may offer other benefits considering its double-dense barrier protection. [Display omitted] • WW served as feed (FS) and SW (35 g/l) as draw (DS) in FO-RO hybrid. • Simulated FS salinities (0.25–1.5 g/l) and FS:DS volume ratios (50:50 to 90:10) • At 0.5 g/l FS and 80:20 FS:DS (volume ratio), FO achieved 90 % FS recovery. • Osmotic dilution in FO-RO hybrid allow for RO operation below 1 kWh/m3. • Existing RO demonstrated adaptability to FO-RO integration. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) is widely accepted for water reuse because it ensures clean water production. However, innovation in the RO process is necessary for water reuse to enhance its recovery while mitigating membrane fouling and reducing the increase in specific energy consumption (SEC). Therefore, circle sequence reverse osmosis (CSRO) adopts a staged design with flow reversal (FR) and a semi-batch design with a jet pump to enhance water flux distribution and energy efficiency for high-recovery water reuse. This study examined the water flux distribution and SEC of CSRO. When the distribution of water flux was compared, CSRO demonstrated a 7.7 % reduction in water flux in the front element compared to semi-batch reverse osmosis (SBRO). This reduction was attributed to advanced designs in SBRO, such as the two-stage design and an FR operation. The SEC of RO systems was also compared under high-recovery conditions. While both SBRO and CSRO achieved SEC reduction of 20–25 % or 9–18 % compared to two-stage RO depending on the feed salinity, CSRO was slightly more energy-efficient for high-saline feed. It is expected that CSRO has excellent potential for high-recovery water reuse, considering the improvement in water flux distribution and energy efficiency. [Display omitted] • Circle sequence reverse osmosis (CSRO) is newly proposed for water reuse. • CSRO adopts a staged design with FR and a semi-batch design with a jet pump. • Design advancements of CSRO were compared with two-stage RO and SBRO. • CSRO effectively concentrated the feed with evenly distributed water flux in RO. • CSRO was more energy-efficient than SBRO for concentrating the high TDS feed. [ABSTRACT FROM AUTHOR]

Hydrogen liquefaction process (HLP) is a principal technology to overcome energy storage and transportation problems and to meet the demand for an eco-friendly energy source. This study proposes three conceptual designs of HLPs with various refrigerant cycles. The specific energy consumption (SEC) of HLP could be reduced by various refrigerants. Three different refrigerants (liquid air (LA)), liquified natural gas (LNG), and mixed refrigerants (MR)) were compared to the conventional LN 2 -based HLP to verify 4E (efficiency, exergy, economics, and environmental) of each process based on their thermodynamic properties. From the results, we found that the process performance, economics, and environmental effects of the LNG-based hydrogen liquefaction process (LNG-HLP) were the best. In particular, the LNG-HLP, which uses the cold energy of LNG, required less refrigerant than LN 2 , thereby reducing the energy consumed by major compressors. It had an SEC of 11.04 KWh/kg-LH 2 and capital, operating cost, and CO 2 emissions of the LNG-HLP process were considerably lower by 5.5 %, 6.2 %, and 12.2 % (unit kg CO 2eq /kg LH 2), respectively, compared to the conventional process. To propose better economic or environmental scenarios to stakeholders and governments, in this study, the HLP and hydrogen production processes were expanded to include CO 2 emission calculation and carried out analysis for levelized cost of hydrogen contribution rate to electricity production types by country. • Proposed a novel conceptual design for hydrogen liquefaction processes. • Analyzed 4E from a comprehensive perspective. • Utilized various refrigerants to improve process efficiency. • LNG-HLP was reduced by 3.7% of LCOH compared to the base process. • LNG-HLP was reduced by 12.2% of CO 2 emissions compared to the base process. [ABSTRACT FROM AUTHOR]

• An autonomous and passive solar pasteurisation process with low specific energy consumption has been developed and tested. • A numerical model combining energy balances and bacteria inactivation has been developed. • Comparison of experimentation and simulation has been carried out. • Assessment of production capacity and performances as a function of various operating conditions has been led. Solar pasteurisation is a simple, robust, and sustainable method for the disinfection of raw water, which can be particularly relevant in remote areas. The process consisted of an open water loop with a flat plate solar collector, a thermostatic valve, a tank and a heat exchanger in series. It was feed with river water supplied by gravity from a tank at 3 m high. It was tested in outdoor conditions with real river water and operated with a fully passive control of the pasteurisation temperature. On sunny days in September, 850 L of water pasteurised at over 60°C and 68°C were produced per day in a reproducible way, i.e. almost 370 L·m−2·day−1. The specific solar energy required was of the order of 15 kWh sol ·m−3. Experimental daily amount of pasteurised water of almost one cubic meter have been achieved by increasing the hydraulic pressure at the inlet of the open water loop. The total absence of the two main bacterial indicators naturally present in the surface water collected, i.e. E. coli and Enterococcus , was verified at the outlet of the process. The development of a numerical model, validated by experimental results obtained, has made it possible to assess the potential field of application of this solar pasteurisation system. [ABSTRACT FROM AUTHOR]

Freshwater scarcity is a growing concern worldwide due to increasing demand and climate change. A promising method that could provide fresh water is seawater desalination. Presently, both thermal- and membrane-based desalination technologies consume a high amount of specific energy (measured in kWh/m3), which limits the use of seawater for drinking purposes. The development of hybrid desalination technologies has the potential to significantly reduce the energy consumption and cost of desalination, making it a more viable solution to address freshwater scarcity. By integrating the advantages of several desalination techniques and eliminating their drawbacks, hybridization can improve system performance. In the current study, a hybrid desalination system was developed by integrating the vacuum membrane distillation (VMD) output into the multi-effect distillation (MED) input. The results indicated a drop in specific thermal energy consumption (STEC) at various feed flow rates and a decrease in STEC in hybrid mode compared to stand-alone VMD.

Green forage maize harvesters face challenges such as high soil humidity and soft soil in the field, mismatched working parameters, and poor reliability and adaptability. These challenges often result in header blockage, significant harvest loss, and increased energy consumption. Traditional testing and statistical analysis methods used in most existing studies are limited by complex test processes, their time-consuming nature, high costs, and poor prediction accuracy. To address these problems, a test bench was constructed to analyze the effects of forward speed, cutting height, number of rows, and their interactions on specific energy consumption and harvest loss of the green forage maize (GFM) header. A combined response surface method (RSM)–artificial neural network (ANN) approach is proposed for modeling and predicting the performance parameters of the header. The optimal conditions were determined by optimizing the specific energy consumption and loss rate. The optimal combination parameters are a forward speed of 1.6 km/h, a cutting height of 167 mm, and a number of rows of 4. However, RSM–ANN has larger R2 values and lower root mean square errors (RMSE) and mean square errors (MSE) compared to RSM. Specifically, the R2 of the RSM–ANN model for specific energy consumption and loss rate a 0.9925 and 0.9906, MSE are 0.00001775 and 0.004558, and RMSE are 0.004214 and 0.006752, respectively. The results show that the combined RSM–ANN method has higher precision and accuracy and can better predict and optimize the header performance. This study overcomes the limitations of traditional methods and has the potential to provide data and method references for the design, optimization, prediction, and intelligent diagnosis of faults in the operational parameters of agricultural machinery.

Abstract A feasibility study was carried out on generation of hydrochloric acid and lithium hydroxide from the simulated lithium chloride solution using EX3B model bipolar membrane electrodialysis (BMED). The influence of a series of process parameters, such as feed concentration, initial acid and base concentration in device component, feed solution volume, and current density were investigated. In addition, the maximum achievable concentrations of HCl and LiOH, the average current efficiency, and specific energy consumption were also studied and compared in this paper to the existing literature. Higher LiCl concentrations in the feed solution were found to be beneficial in increasing the final concentrations of HCl and LiOH, as well as improving current efficiency while decreasing specific energy consumption. However, when its concentration was less than 4 g/L, the membrane stack voltage curve of BMED increased rapidly, attributed to the higher solution resistance. Also low initial concentration of acid and base employed in device component can improve the current efficiency. Increasing of the initial concentration of acid and base solution lowered energy consumption. Moreover, a high current density could rapidly increase HCl and LiOH concentration and enhance water movements of BMED process, but reduced the current efficiency. The maximum achievable concentration of HCl and LiOH generated from 130 g/L LiCl solution were close to 3.24 mol/L and 3.57 mol/L, respectively. In summary, the present study confirmed the feasible application for the generation of HCl and LiOH from simulated lithium chloride solution with BMED.

Variable-frequency drive (VFD) has been widely used in reverse osmosis desalination. Our purpose is to study how the VFD and pressure regulating valve affect the key parameters of reverse osmosis desalination and their action principle through experiments. Firstly, the power frequency is controlled by VFD, and the operating pressure is controlled by pressure regulating valve (needle valve) in the experiment. The feed water passes through the multimedia filter, precision filter and permeable membrane channel in turn, and permeate water and brine enter the fresh water tank and the brine tank respectively. Secondly, through experiments on seawater and brackish water respectively, the water flow rate, product water quality, energy consumption and recovery rate under different operating pressures are obtained when the power frequency is 25, 30, 35, 40, 45, and 50 respectively. Finally, combined with the working principle and mathematical model of VFD and high-pressure pump motor, the reason for the experimental results caused by the operation change is explained theoretically. The experimental results verify that for a certain recovery rate, the specific energy consumption required for water production decreases with decreasing power frequency. This provides desalination energy savings but at the expense of permeate production speed.

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.

The results of the analytical study substantiated the operating conditions for the highly efficient use of the temperature potential of seawater in heat pump heating systems (HPHS) for buildings a building with correspondingly improved environmental indicators. Based on the analysis of the regional conditions of the Odessa water area of the Black Sea, the initial parameters have been substantiated and rational modes of operation of an improved HPHS with central, decentralized or local heating of the subscriber energy carrier have been determined. As indicators for evaluating the efficiency of the HPHS operation, the conversion factor of energy flows and the specific consumption of external energy for the drive of the compressor and the circulating pump of cooled water in the operation of heat pump units were considered. For seawater in the Odessa water area of the Black Sea during the entire heating period, the following temperatures were considered as initial data for analysis: water at the inlet to the evaporator (5–10) ° C, at the outlet (1 °C); calculated temperature difference of the coolant in the heating system (50–40) °C, indoor air (20 °C); estimated outdoor temperature (–18 °C). The characteristic correspondence between the flow rates of the cooled sea water and the heated energy carrier of the heat supply system was taken into account. The prerequisites of high efficiency of the heat pump heat supply system in which the actual conversion coefficient exceeds the seasonal normalized calculated and minimum value at an outdoor temperature of (–10) °C under the limiting conditions of the monoenergy regime for both new and reconstructed buildings were substantiated. In the course of the study, it has been determined that the total specific consumption of external energy for the compressor drive and the circulation of cooled water in the operation of a heat pump unit with a characteristic ratio of water equivalents, even under the limiting conditions of the monoenergetic mode of operation of the heat supply system at an outdoor temperature of (–10) °C, are within the range of generally accepted values (w = 0.28–0.34).

Optimised solar air dryers, in terms of efficiency and performance, can solve some major concerns in the agro-industrial processing sector. Solar air dryers can reduce the large share of energy costs of a final product and can provide sustainable energy in rural areas where access to energy is often limited. In this study, a pilot scale v-groove double pass solar air collector has been analysed thermodynamically with real time solar radiation and mass flow rate (0.021–0.061 kg/s) inputs and validated experimentally in terms of first and second law efficiencies. Performance of the process was assessed using experimental drying measures including final moisture content, drying rate and exergy efficiency for drying of Pink Lady apples. Energy payback time and specific energy consumption were calculated to reveal the techno-economic value of the system. The maximum thermal efficiency of the collector was observed to be 88.8 % at 0.061 kg/s having exergy efficiency of 6.6 % which shows an efficient sourcing for the operation. In terms of the performance of the dryer, mass flow rate of 0.041 kg/s offers a higher moisture removal. Specific energy consumption (SEC) was 3.096 kWh/kg. Thermodynamic model was validated with matching experimentation with acceptable RMSE for the range of investigated measures. Energy payback period time calculated by the embodied energy of the system was obtained to be 0.78 years which implies that the system is capable of addressing a large capacity drying if it is to be scaled-up.

Ceramic production chain consisting of discrete flow and continuous flow energy-intensive processes consumes substantial amounts of energy. This study aims to evaluate energy consumption performance and energy-saving potentials of the ceramic production chain. According to the energy consumption characteristics of manufacturing processes and process interaction constraints in a ceramic production chain, an approach integrating the first-order hybrid Petri net (FOHPN) model, an objective linear programming model and a sensitivity analysis is proposed. The FOHPN model will simulate the energy consumption patterns of the ceramic production chain. Meanwhile, multi-objective linear programming model and sensitivity analysis will suggest the optimal specific energy consumption (SEC) of the production chain and identify the influences of input parameters (i.e. production rate of a process) on the SEC in the optimal production scheme. Finally, a real case study from bathroom ceramic plant validates the approach. It provides a tool for modelling and simulation of energy consumption of ceramic production chains with mixed flows and helps operators to perform energy-saving actions in the ceramic enterprise. [ABSTRACT FROM AUTHOR]

Jordan was late in adopting seawater and brackish water desalination as a source until the late 1990s and early 2000s. However, ongoing studies are still discussing the technical, economic, and socio-political aspects of brackish water reverse osmosis (BWRO) desalination plants. In this study, the water–energy nexus was considered, in order to highlight the main challenges facing BWRO desalination. We discuss the use of photovoltaic (PV) technology, together with BWRO desalination, as an approach to compensate for ecological, financial, and social challenges in Jordan. For this purpose, the performance of nine existing BWRO desalination plants in the agricultural, domestic, and industrial sectors is assessed. The water performance is assessed based on water consumption, safe yield extraction, plant recovery rate (R, %), and compliance to local and international water quality standards; the Specific Energy Consumption (SEC, kWh/m3) is taken as the main evaluation criterion to assess the energy performance of the BWRO desalination plants; and economic performance is assessed based on the overall cost of water produced per cubic meter (USD/m3). The main environmental component is the brine disposal management practice utilized by each plant. Based on this assessment, the main challenges in BWRO desalination are the unsustainable patterns of water production, mismanaged energy performance, low recovery rates, and improper brine disposal. The challenges in domestic and industrial BWRO desalination, which are completely dependent on the electricity grid, are associated with critical energy and costs losses, as reflected by the high SEC values (in the range of 2.7–5.6 kWh/m3) and high water costs per cubic meter (0.60–1.18 USD/m3). As such, the use of PV solar panels is suggested, in order to reduce the electricity consumption of the assessed BWRO plants. The installation of PV panels resulted in significantly reduced energy costs (by 69–74%) and total costs (by 50–54%), compared with energy costs from the electricity grid, over the lifetime of the assessed BWRO desalination plants. [ABSTRACT FROM AUTHOR]

The continuous production of fatty acid methyl ester (FAME) from waste cooking oil (WCO) via transesterification was carried out under theoretical methanol to oil molar ratio using a high-performance bumpy surface rotor reactor (BSRR). Three types of rotors with different area fractions (AF) of 6.9%, 13.8% and 27.6% were used to equip the BSRR. The selection of the highest performance rotor was compared by factorial experiments. Absolute methanol with 99.9 vol% purity was used as the reactant and potassium hydroxide with 90 wt% purity was used as the base catalyst. Response surface methodology (RSM) was applied to design the experiments and predict the optimal conditions. The three variables in RSM were 0.58-1.43 wt% potassium hydroxide concentration [KOH], 2160-3840 rpm rotor speed, and 1.38- 4.74 L/min flow rate. The performance was the specific energy consumption (SEC). The highest performance rotor was AF27.6%. In the first step, the transesterification process was performed using [KOH] 1.5 wt%, a rotor speed of 3000 rpm and a flow rate of 2.027 L/min to produce 98.6 wt% FAME and using SEC at 12.5 W h/kg. In the second step, RSM predicted the optimal condition of [KOH] 1.016 wt%, rotor speed 2910 rpm, flow rate 2.134 L/min and FAME content 97.3 wt%. The actual FAME content averaged 97.16 wt%. The biodiesel properties complied with the EN 14214 standard. This biodiesel production can reduce the cost of methanol by one-half and the cost of KOH by one-third. The energy consumption is only 0.012 kW・h/kg, so the methanol recovery process is not necessary. It has low KOH residue, so washing with water is superfluous and uses minimal energy, which can reduce a lot of costs. The high flow rate of 128 L/h can be used to scale up commercial production. [ABSTRACT FROM AUTHOR]

Highlights: Positive influence of the media through wastewater dilution to permeate quality. Reduction in COD removal efficiency with an increase in pressure due to interactions between negative sites on the membrane and ions in solution. Optimal energy consumption attained an efficient process for high quality treated wastewater. Solution pH and composition changes ion and membrane charge and decreases selectivity. This study was conducted to eliminate the ions and molecules present in the industrial wastewater received by the municipal wastewater treatment plant (WWTP) of Reghaia, which is located east of Algiers, Algeria. The process was developed for two different study matrices: (a) the wastewater from WWTP and (b) wastewater mixed with Brilliant Blue FCF (BBF) dye to show the influence of the strength of the ionic solution on the treatment. The most effective operating parameters were determined by assessing the residence time distribution applied to the reactor flow regime. Energy analysis showed the viability of a nanofiltration membrane, improving the permeate flux. The nanofiltration process consumed 1.94 kWh/m3 to reduce the chemical oxygen demand (COD) of 63.58% and 48.35% for raw wastewater and doped BBF wastewater, respectively. The results demonstrated that nanofiltration performance with a volume dilution ratio of 1/2 showed the reduction of the COD of 87.2% after 15 min for undoped wastewater, whereas the retention rate decreases to 64% with an increase of dilution ratio to 4/5 for the same water matrix. The influence of a pH of 5 has a significant influence on the composition of the wastewater matrix by the reduction of COD of 49.8% and 59.68% for doped wastewater and raw wastewater, respectively. This could be explained by the isolated points of the membrane in the order of 4.5. [ABSTRACT FROM AUTHOR]

The resource efficiency of a conventional domestic reverse osmosis system is low because it operates at a low water recovery and energy efficiency. Besides, the quality of permeate cannot be controlled, leading to unusual taste, which may result in adverse health effects. In this article, a new system design and operational method of a domestic reverse osmosis system have been studied analytically and experimentally. The study shows that it is possible to tune the permeate quality, and a high water recovery can be achieved with this design and operational method. In addition, specific energy consumption can be reduced. This system is particularly useful in the case of low salinity feed with a trace amount of heavy metals. A synthetic feed solution of As+5 in pure water was used as a feed to verify the same. It was observed that a high water recovery (>85%) could be achieved while removing As+5 from the water. With global rise in decentralized desalination systems, the proposed system design and operational method can be used not only to tune the product recovery and quality but also to reduce the specific energy consumption as well. Hence, this work is in line with United Nations Sustainable Development goals (SDGs). [ABSTRACT FROM AUTHOR]

In the present study, the degradation of methylene blue (MB) dye, a common pollutant from textile and printing industries was observed using UV/H2O2 advanced oxidation process. Effect of process variables like pH (3-11), H2O2 dosage (2.5-12.5) mM and initial MB dose (10-100) mg/L on decolorization efficiency of dye was investigated. An acidic pH of 3 was found to be favorable for decolorization of MB. Degradation of MB followed pseudo-first-order removal kinetics. Rate constants of MB decolorization increased with increase in H2O2 concentration and decrease in initial dye concentration. The results showed that about 89.85% residual H2O2 remained in the system even after 75 min treatment time. To ensure the minimum residual H2O2 in effluent and optimum MB removal, H2O2 dose was optimized at 12.5 mM with specific energy consumption of 271.6 kWh/kg dye. Thus, in the described experimental range of conditions, UV/H2O2 oxidation of MB may be an efficient, inexpensive and clean alternative treatment for decolorization of textile wastewater containing this dye. [ABSTRACT FROM AUTHOR]

Laser welding is an indispensable part of competitive manufacturing, but it has a critical issue with energy consumption. The existing literature is limited to the energy supplied to the laser-material interaction for the material welding, and the welding quality is not well considered for energy saving. To reduce the total energy consumption of laser welding without compromising the welding quality, this study investigates the effects of process parameters including the laser power, welding speed and focus position on the specific energy consumption (SEC), welding quality and related energy effectiveness (EE) of the laser welding of 6061 aluminium alloy. The results reveal that adjusting the laser power to improve the welding quality will inevitably lead to a significant increase in the SEC. Energy can be saved with a relatively stable welding quality by varying the welding speed, and the welding quality can be improved without appreciably increasing the energy consumption by setting the focus position to approximately −0.5 mm. The EE can be enhanced with a higher laser power within a moderate welding speed range at the negative focus position. A case demonstrated that with a reasonable process parameter configuration, an energy savings of 12.45% could be realised for laser welding, while the tensile strength was increased by 4.29%, and the weld bead integrity remained stable (a decrease of 0.11%). [ABSTRACT FROM AUTHOR]

Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. This study aims to (i) assess the progress of solar energy systems including concentrated solar power (CSP) and photovoltaic (PV) to power both thermal and membrane seawater desalination processes including MSF, MED, and RO and (ii) evaluate the economic considerations and associated challenges with recommendations for further improvements. Thus, several studies on a different combination of seawater desalination processes of solar energy systems are reviewed and analysed concerning specific energy consumption and freshwater production cost. It is observed that although solar energy systems have the potential of reducing carbon footprint significantly, the cost of water production still favours the use of fossil fuels. Further research and development on solar energy systems are required to make their use in desalination economically viable. Alternatively, the carbon tax on the use of fossil fuels may persuade desalination industries to adopt renewable energy such as solar. [ABSTRACT FROM AUTHOR]

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 factors, such as voltage, current, environmental conditions, drying material, and electrodes geometry. This research is exploring the effect of collecting electrode geometry on the drying rate and energy efficiency of EHD drying. Although numerical studies predict a better performance of mesh collectors compared to solid plate collectors, experimental verification is still missing. This research addresses this gap by comparing the performance of plate versus mesh collecting electrodes in drying experiments with three discharge electrodes (nails, needles, pins) and two materials (wet paper and apple slices). Our experiments confirmed the benefits of mesh collector compared to the plate, namely up to 25% higher drying flux and a 20–35% smaller specific energy consumption. For example, EHD drying of apple slices with the mesh resulted in specific energy consumption of 719–731 kJ/kg compared to 935–968 kJ/kg with the plate collector. The better energy efficiency of the mesh collector provides a unique opportunity for the industrial upscaling of EHD drying technology. [ABSTRACT FROM AUTHOR]

The possibility of building liquefied natural gas (LNG) plants of 5-20 tons/h capacity with an external nitrogen refrigeration cycle as an alternative to mixed cycles is investigated. A computational analysis is made and various schemes of natural gas liquefaction with external expansion cycle are compared. Scheme with two expanders is preferable for plants with capacities up to 20 tons/h. The main technical solutions ensuring versatility of the plant with sufficiently high efficiency are worked out. A design of a 5 tons/h LNG plant based on external nitrogen expansion cycle with two expanders is developed for a specific customer. [ABSTRACT FROM AUTHOR]

Drying of agricultural products inherently is an energy intensive process. In the majority of drying processes, the energy for the air heating process is delivered by the steam, gas‐turbine, and combined‐cycle type power plants that run on the fossil fuels which in turn are responsible for global warming due to the greenhouse phenomena. The industry therefore is interested in the development of any energy saving measure in the drying process. This in turn reduces greenhouse gas (GHG) emissions. Optimization of the drying process for energy reduction by the mathematical modeling may provide means to accomplish this goal. In the present study, the drying of canola seeds in a fluidized bed dryer containing heat carrier particles was investigated. Drying kinetics was modeled using dimensionless groups and the GHG emissions in each process were determined and analyzed. Three temperature levels and four ratios of Heat Carrier Particle (HCP) to seeds were applied. The lowest specific energy consumption (least GHG emissions) was achieved when the air temperature was set at 60°C and the drying chamber was filled with a mass ratio of 0.5 of HCP to seeds. Values of R2, RMSE, and k2 obtained for the predicted and experimental data were 0.90, 0.017, and 0.00092 respectively. Practical applications: In the current investigation, specific energy consumption and GHG emissions in different drying conditions of canola seeds in a fluidized bed dryer containing heat carrier particles were calculated and compared. A dimensionless approach was used to establish a new model for drying of canola seeds in the fluidized bed dryer. Subsequently, a dimensionless equation describing the drying behavior of seeds was derived. This method while being a simple model, gives high precision data for all effective parameters in the drying process. Therefore, the establishment of a dimensionless model for the drying kinetics and investigation of GHG emissions in the present study can be useful for the development of Eco‐friendly drying methods for future usages in food process engineering. [ABSTRACT FROM AUTHOR]

IntroductionSome unit operations of food process engineering such as drying consumes a high amount of energy. Therefore, analysis of energy and exergy can be a suitable method to manage the energy consumption of the drying. Hence, in the present research, analysis of energy and exergy for the drying process of lemon verbena leaves was performed.Materials and MethodsA cabinet solar dryer was employed to investigate the energy consumption of thin layer drying of lemon verbena leaves. The dryer had a galvanized solar plate collector which had a surface area of 0.75 m2 and to absorb the maximum solar energy, the collector painted with the black color. The collector was set at an angle of 45 degrees relative to the horizon and an electric blower was installed in the bottom of the collector to blow the ambient air through the solar collector and hence, hot air entered the drying chamber to dry the lemon verbena leaves. In order to record the air temperature and humidity in different locations of the dryer, an Arduino board with 8 smart sensors (AM2301, with temperature accuracy of 0.5°C and humidity accuracy of 3%) were used. To obtain the initial moisture content of the leaves, they inserted in an electrical oven for 16 hours at a temperature of 70°C. In order to measure the moisture content of the leaves during drying, they weighted at different times using a digital balance (A & D, Japan with accuracy of 0.001 g).Energy consumption rate of the drying was calculated by Equation (1):Where, Ein: energy consumption rate (kW), : mass flow rate of drying air (kg s-1), cp: specific heat of drying air (kJ kg-1 °C-1), Δt: temperature difference between the ambient air and drying air (°C).Also, the specific energy consumption of drying (SEC) was calculated by Equation (2):Where; SEC: Specific energy consumption (MJ kg-1 of removed water) t: drying time (s), and M: mass of removed water from the drying material (kg).Also, useful power can be calculated from Equation (3):Where; Eout: useful power (kW), ms: Evaporation rate (kg s-1), lg: latent heat of vaporization (kJ kg-1 of water)In order to calculate energy efficiency, Equation (4) was used: Also inlet and outlet exergy were calculated by equations (5) and (6), respectively: Where; T1: Inlet air temperature into the drying chamber (°C), T2: Outlet air temperature from the drying chamber (°C), T0: Ambient air temperature (°C).Also, Equations (7) and (8) were used to calculate exergy efficiency and loss, respectively:Results and DiscussionThe results of energy analysis showed specific energy consumption (SEC) increased with increasing of drying temperature and decreasing of air velocity. Accordingly, in the air velocity of 2 m s-1 and the temperatures of 30, 40, and 50 ˚C, SEC were 276.3, 694.7, and 708.0 MJ kg-1 of removed water, respectively. While SEC for an air velocity of 2.5 m s-1 and air temperatures of 30, 40, and 50 ˚C were 266.9, 469.8, and 638.0 MJ kg-1 of removed water, respectively, the corresponded values for air velocity of 3 m s-1 were as 217.0, 391.3, and 501.8 MJ kg-1 of removed water, respectively. Also, the results revealed that with an increase of temperature and a reduction of velocity, energy efficiency reduced, so that the maximum value of energy efficiency observed in an experiment with temperature of 30˚C and velocity of 3 m s-1. Also, the highest value of exergy efficiency obtained in temperature of 50˚C and velocity of 3 m s-1.ConclusionsA hot air solar dryer was used for drying lemon verbena leaves. Results of specific energy consumption of drying showed a high amount of fossil fuels can be saved by using this dryer. Also, from the aspect of energy and exergy efficiency, using of the dryer in the lower temperature and higher air velocity is recommended.

The study presents an energy-efficient desalination system that combines direct contact membrane distillation (DCMD) and a heat pump to improve thermal efficiency and integrate with photovoltaics. DCMD is a sort of thermal desalination process, and it requires a lot of thermal energy. A heat pump is a device that produces both hot and cold energy simultaneously with less electrical energy input compared to other heating devices, such as a boiler and an electrical heater. A hollow-fiber DCMD and a 10-kW water-to-water heat pump were considered for a numerical simulation in this study. Numerical models were established for each device and validated against the results obtained from the literature. The simulation was first carried out to identify the performance of the system based on the baseline. After that, a series of simulations were carried out in order to investigate the performance of the proposed system in terms of specific energy consumption (SEC), gained output ratio (GOR), and the coefficient of performance (COP) under various operating conditions. Results showed that the minimum SEC and the maximum GOR were achieved at the inlet feed water temperature of 66.5°C with a mass flow rate of 20 kg/min and the inlet permeate temperature of 19.8°C with a mass flow rate of 10 lpm. On the other hand, it was found that the maximum COP can be observed at the inlet feed water temperature of 23.6°C with a mass flow rate of 10 lpm and at the inlet permeate temperature of 8.9°C with a mass flow rate of 20 lpm.

Effects of drying temperature (60, 70, and 80 °C) and air velocity (3.0, 6.0, and 9.0 m/s) on thin layer and color kinetics of maize grain during mixed flow dryer (MFD) were investigated for the present study. Five thin layer grain drying models (Henderson and Pabis, Page, Lewis, Midilli et al. and Wang and Singh) as well as Zero order reaction rate were applied with the experimental data to predict the drying and color kinetics of maize, respectively. Increased drying temperature had significant leverage on drying time whereas proliferation of air velocity (>6.0 m/s) is scarcely imperative. Model fitting analysis revealed that Lewis and Page model is aptly applied in evaluating drying kinetics for mixed flow drying of maize as coefficient of determination (R2) is higher. Effective moisture diffusivity (4.92 × 10−7 to 8.38 × 10−7 m2/s) was maximum both for higher temperature and air flow whereas specific energy consumption was lowest (2.75 MJ/kg) for lower temperature and air flow. Regression analysis of color attributes (L*, a*, and b*) designates that color kinetics of maize grain occurred according to the zero order reaction. L* and b* indices of color decreases while a* and color difference (ΔE) increases with drying temperature and time. Thin layer and kinetic constant (k) is proportionate with drying temperature while adverse results were noticed for color attributes. Drying and color degradation kinetics of maize can readily be described by Lewis and Page model and zero order reaction, respectively for mixed flow drying.

The aim of this study is to use the response surface methodology (RSM) to mathematically model the response parameters and emission of greenhouse gases (GHG) and optimize the drying variables for a carrot dried with the microwave method using various pretreatments. To this end, the influence of the drying parameters (independent), such as microwave power and slice thickness dried by two pretreatments of ultrasonication at 30 °C for 10 min and blanching at 70 ℃ for 2 min, was explored on the dependent (response) parameters including the thermal properties (drying time, effective moisture diffusion coefficient (Deff), specific energy consumption, energy efficiency, quality features (color changes and shrinkage), and GHG emission (including CO2 and NOx). It should be mentioned that the emission of GHG was determined based on the energy consumption of various types of power plants such as the gas turbine steam power turbine, and combined cycle turbines using various fuels such as natural gas, heavy oil, and gas oil. The results indicated that the ultrasonication and blanching pretreatments can decrement the drying time (linearly), energy consumption (linearly or quadratically), shrinkage(quadratically), and color changes(quadratically) and enhance the Deff (linearly) and energy efficiency (linearly or quadratically) in all samples with R2 > 0.86. Moreover, the shortest drying time (42 min), lowest SEC (9.51 MJ/kg), and GHG emission ((4279.74 g CO2 in the combined cycle turbines plant, and 18.16 g NOX in the gas turbine plant) with natural gas for both plants) were recorded for the samples pretreated with blanching while the lowest color changes (13.69) and shrinkage (21.29) were observed in the ultrasonicated samples. Based on the optimization results, a microwave power of 300 W and steam power turbine of 2 mm were the best variables with a desirability of about 80% which resulted in the highest-quality products at the lowest GHG emission.

Although DC power is claimed to be more energy-efficient than AC power for EHD drying, experimental studies on this subject are still insufficient. This research compares the efficiency of DC versus AC (60 Hz frequency) power for EHD drying by using 1 × 1 and 2 × 2 multi-pin discharge electrodes. Energy indicators were determined from the measurements of electric power consumption at the corresponding drying rate of the wet tissue paper. The experiments revealed the key benefits of DC drying, such as enhanced drying rate, higher energy efficiency, and lower specific energy consumption. For the comparable drying flux of 0.2 g/(m2 s), the specific energy consumption of DC drying was in the range from 350 J/g (2 × 2) to 750 J/g (1 × 1) as compared with 2000 J/g (2 × 2) to 5000 J/g (1 × 1) for AC. The specific energy consumption of a 2 × 2 discharge electrode was consistently smaller than the 1 × 1 one, indicating the role of emitters spacing in the process efficiency. The specific energy consumption of both electrodes increased with the drying rate. [ABSTRACT FROM AUTHOR]

The soybean (Glycine max) is used as one of the main protein sources in various animal fodders. However, the presence of anti-nutrients significantly reduces the nutritional value of the bean. To solve this problem, the present work is devoted to the inactivation of the anti-nutrients in soybeans by the use of micronisation as a means of thermal treatment. The purpose of the work is to improve the process of soybean micronisation by determining the impact of the process parameters on the soybean's quality and energy performance, namely -- the urease activity and specific energy consumption. A multifactor experiment was carried out using an experimental device for the heat treatment of the beans. The influence of the temperature and time of the heat treatment on the level of inactivation of anti-nutrients and the specific energy consumption for beans with different sizes were established. The modes of heat treatment which allow the inactivation of the anti-nutrients in the soybeans to admissible standard values were also defined. The obtained and studied functional dependencies of the quality and energy indices on the technological factors of the soybean micronisation allow one to improve this process and technical means for its implementation in reducing the anti-nutrient content. [ABSTRACT FROM AUTHOR]