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A microwave-hot air belt dryer (MHABD) showed high specific energy consumption (SEC) due to its limited material processing capacity and extended drying time. Thus, this research presents the development and performance evaluation of an industrial microwave-hot air belt dryer (IMHABD) for drying Namdokmai Sithong mango slices. The IMHABD system, optimized using the COMSOL Multiphysics program, features a 0.9 m × 4.08 m × 0.5 m chamber with 36 magnetrons having a maximum microwave power of 28,800 W (each magnetron produces 800 W) at a frequency of 2,450 MHz. Two drying methods were studied, step-down microwave power drying (IMHABD-S) and constant microwave power drying (IMHABD-C). IMHABD-S, with a power range of 150–350 W combined with hot air at 65 °C, outperformed IMHABD-C, delivering enhanced drying rates, improved color attributes, and reduced shrinkage, along with decreased hardness and toughness values. All dried slices had a water activity lower than 0.6. An IMHABD-S operated at 350 W for 1.5 h showed the lowest SEC. Economic analysis revealed strong support for the IMHABD process, with a net present value (NPV) of 13,647 USD, an internal rate of return (IRR) of 15%, and a 4.95-year payback with a 10-year service life, highlighting its technical efficacy and economic viability for mango drying applications. [ABSTRACT FROM AUTHOR]

This study addresses the challenge of processing undersized or overripe mangoes by integrating microwave heating with traditional foam-mat drying technique. The study aims at investigating drying kinetics coupled with thin-layer drying modeling and influences of microwave power (300 - 600 W) and hot-air temperature (55 - 75 °C). Among ten drying models, the so-called Midilli equation fitted well with experimental data. Results showed enhanced drying process associated with microwave heating, providing reduced drying time from 600 - 700 min (for conventional hot-air mode) to 30 - 100 min (for microwave-assisted mode). Standard deviations of moisture content and dried foam thickness measured at various points revealed uneven heat distribution when using high microwave energy, evidenced by burnt spots at 600 W. Additionally, foam collapse was observed under the mild process with low microwave powers, possibly due to prolonged drying periods. Response surface methodology demonstrated that microwave power was more important factor, positively affecting effective diffusivity coefficient (Deff) while inversely influencing specific energy consumption (SEC) and color difference (ΔE). Deff value increased from 5.41x10-6 m²·s-1 at 300 W and 55 °C to 18.43x10-6 m²·s-1 at 600 W and 75 °C, confirming enhance drying performance. As assisted with microwave heating, drying foamed mango sample consumed less energy up to 92 %. Optimal drying parameters were determined based on balancing the enhancement of drying performance and color alteration, suggesting drying the thick foamed mango pulp at temperature of 55 °C combined with microwave heating at 520 W, which can be served as a basis for further industrial scale-up. [ABSTRACT FROM AUTHOR]

This article describes elements of the know-how of using carbon electrodes produced using the technology of molding around a rod when smelting silicon metal. Application of our know-how will dramatically increase the competitiveness of silicon metal production. Experts' concerns regarding the use of such electrodes were that such electrodes have a through axial hole. This significantly reduces the mechanical strength of such electrodes, which can presumably lead to problems associated with the breakage of the working side of the electrode, which is immersed in the smelting space of the furnace under the charge layer. Industrial testing of such electrodes was carried out in a 30 MVA furnace of "Tau-Ken Temir" LLP. During testing, we used an approach previously developed by our team for working with a furnace in the process of smelting silicon metal. In particular, we used an interval between top treatments of about 30 min and adhered to the principles of balanced smelting, i.e., provided a balance between the intensity of the uniform supply of the charge into the furnace and the current active electrical power. Industrial testing carried out over four weeks confirmed the stability of the operation of cheaper carbon electrodes with a through axial hole. The recovery of silicon into finished products was also improved to 88–89% and the specific energy consumption was reduced to 11.2–12.1 MWh/t of silicon metal from the initial value 14,752 MWh/t. Thus, we received additional evidence for the effectiveness of our approach in furnace operating compared to an approach based on the ultimate provision of gas and permeability of the furnace top due to excessively intense processing of the top and an uncontrolled, uneven supply of charge to the furnace. [ABSTRACT FROM AUTHOR]

In agriculture, the transformation and drying industries have the most share of energy consumption. The present study aims to optimize the drying process of apple pulp sheets. This process includes checking the energy consumption values and emission of greenhouse gases by the vacuum system in the normal atmosphere (Natm) and controlled atmosphere (Catm) methods. Experiments were conducted at five drying chamber temperatures (i.e., 45, 55, 65, 75, and 85 ℃) and five vacuum pressures (i.e., 40, 50, 60, 70 and 80 kPa). Optimizations were performed using the response surface methodology and the central composite design. The optimum point of apple pulp sheets drying for a gas turbine-oil gas power plant was obtained at a drying temperature of 84.9 ℃ and vacuum pressure of 60.6 kPa. The desirability index was 0.9936 under these conditions. Besides, the optimal value of the response variables, including drying time, total energy consumption (EC), specific energy consumption (SEC), NOX emission, and CO2 emission, were 205 min, 7.65 kWh, 339.02 kWh/kgwater, 1962.94 g/kgwater, and 210,872.40 g/kgwater, respectively. The results showed that in the Catm method, the EC, SEC, NOX, and CO2 from the oil gas turbine power plant were about 19.22%, 37.19%, 37.19%, and 62.72% less than the Natm method, respectively. Therefore, using a vacuum dryer and applying the Catm method in the gas turbine oil of a gas power plant is more economical regarding environmental pollution than the vacuum dryer using the Natm method. [ABSTRACT FROM AUTHOR]

Walnut green husk (WGH) is a common agricultural by-product with high yield and serious pollution problem. The present study aimed to evaluate the impacts of sun drying (SD), pulsed vacuum drying (PVD), short and medium infrared radiation drying (SMIR), hot air drying based on temperature and humidity control (TH-HAD), and heat pump drying (HPD) on the drying characteristics, energy consumption, physico-chemical properties, bioactive compounds content and antioxidant capacity of WGH. Drying characteristics and drying kinetics showed that artificial drying could significantly improve drying efficiency. Compared with SD, the drying time of PVD, SMIR, TH-HAD, and HPD reduced by 63.6, 78.7, 66.3, and 54.0%, respectively. Specific energy consumption analysis demonstrated that HPD showed the lowest specific energy consumption of 2.2 kW·h/kg. Hydration properties analysis revealed that PVD resulted in sample of best water-holding capacity and the HPD sample had the highest water solubility index (43.44%). Structural analysis showed that the cell wall structure of WGH was damaged by different drying methods. Generally, among the five drying methods, HPD was found to be in the middle range in terms of active substance content and antioxidant capacity of dried samples, but it had the least energy consumption. Therefore, HPD has great potential for commercial-scale drying of WGH, offering a new approach for low-energy food processing. [ABSTRACT FROM AUTHOR]

Water shows a strong tendency to absorb the energy of wavelengths of 3 and 6 µm, which are in the infrared (IR) range. Therefore, IR dryers are used to dry food and fruits that have a high‐water content. Thus, modeling and optimizing energy and exergy parameters of terebinth drying in an IR–rotary drum (RD) dryer were evaluated using the response surface methodology. Independent factors included IR power and rotary rotation speed, and response factors were specific energy consumption (SEC), energy efficiency (EFF), exergy efficiency (EXEFF), specific exergy loss (EXLOSS), and exergy improvement potential (EIP). According to the obtained results, the range of EFF and EXEFF was between 28.93%–9.11% and 0.88%–6.62%, respectively. As IR power and RD speed increased, SEC (123.75–39.21 MJ/kg), EXLOSS (3.97–2.97 MJ/kg), and EIP (3.62–1.009 MJ/kg) decreased, while EFF and EXEFF increased. The results obtained in this study showed that the optimal IR drying power is 616.39 W, and the optimal rotary rotation speed is 13.46 rpm. [ABSTRACT FROM AUTHOR]

Abstract Background Reducing energy consumption and greenhouse gas emissions is a crucial issue in the cassava starch processing industry. In this study, the integrated system combining livestock, cassava cultivation and cassava production in the same area leads to both a zero emission goal and economic efficiency, a typical example of an effective agro-industrial symbiosis. A heat exchange/recovery system was applied including the economizer, heat exchanger tank, biogas tank, and boiler. The economizer attached to the boiler’s chimney transfers heat from exhaust gases for pre-heating feed water entering the boiler. The biogas tank recovers energy from the wastewater of starch production and livestock, and the generated biogas was used as fuel for the boiler. Results The energy and exergy efficiency, energy losses, and exergy destruction for the heat recovery system were analyzed. The specific energy consumption was used to evaluate the overall energy efficiency for a cassava starch factory with a capacity of 20 tons/day. The results show that there is a high potential to recycle waste into energy in the cassava starch industry. The total energy saving and reduced greenhouse gas emissions per year of the cassava starch factory were 0.054%/year and 123,564 kgCO2/per year, respectively. Conclusions Cassava starch factories can save energy and reduce emissions when applying a heat recovery system in the integrated agro-industrial system. Excess heat from the production was used for evaporating (removal of) NH3 in wastewater flow from the biogas tank, and for heating the biogas system to enhance the efficiency of methane production. A biochar filter was attached to the economizer for adsorption of released ammonium, and the biochar after adsorption was combined with sludge from the biogas tank to produce a solid biofertilizer.

The efficient and effective operation of trommel screens is essential for the economic and environmental sustainability of mechanical biological treatment (MBT) based solid waste treatment plants. The present study evaluated the performance of four trommel screens (aperture sizes of 80, 32, 16, and 4 mm) being used at the MBT plant of the Municipal Corporation Karnal, India. The performance of trommel screens was evaluated at a fixed speed of rotation and inclination angle. For optimum performance, trommel screens must be operated at a particular range of feed rates with regular cleaning every four hours of operation. The organic recovery achieved by 80 mm and 32 mm aperture size trommel screen was 26.95 % and 95.82 %. The organic quality improvement achieved by 80 mm and 32 mm trommel screens was 122.50 % and 108.89 %. The trommel screen's heating value improvement and energy recovery ranged from 70.68 % to 135.16 % and 28.27 % to 98.74 %, respectively. The oversized fractions of trommel screens of opening sizes 80 mm and 32 mm meet the fuel specification prescribed by the Indian Solid Waste Management Rules 2016. The trommel screen's Specific Energy Consumption (SEC) ranged from 0.63 kWh/tonne to 5.66 kWh/tonne. The learnings and outcomes of this study are helpful for designers, policymakers, operators of solid waste treatment plants, and researchers.

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Reducing energy consumption and greenhouse gas emissions is a crucial issue in the cassava starch processing industry. In this study, the integrated system combining livestock, cassava cultivation and cassava production in the same area leads to both a zero emission goal and economic efficiency, a typical example of an effective agro-industrial symbiosis. A heat exchange/recovery system was applied including the economizer, heat exchanger tank, biogas tank, and boiler. The economizer attached to the boiler's chimney transfers heat from exhaust gases for pre-heating feed water entering the boiler. The biogas tank recovers energy from the wastewater of starch production and livestock, and the generated biogas was used as fuel for the boiler. Results: The energy and exergy efficiency, energy losses, and exergy destruction for the heat recovery system were analyzed. The specific energy consumption was used to evaluate the overall energy efficiency for a cassava starch factory with a capacity of 20 tons/day. The results show that there is a high potential to recycle waste into energy in the cassava starch industry. The total energy saving and reduced greenhouse gas emissions per year of the cassava starch factory were 0.054%/year and 123,564 kgCO2/per year, respectively. Conclusions: Cassava starch factories can save energy and reduce emissions when applying a heat recovery system in the integrated agro-industrial system. Excess heat from the production was used for evaporating (removal of) NH3 in wastewater flow from the biogas tank, and for heating the biogas system to enhance the efficiency of methane production. A biochar filter was attached to the economizer for adsorption of released ammonium, and the biochar after adsorption was combined with sludge from the biogas tank to produce a solid biofertilizer. [ABSTRACT FROM AUTHOR]

The use of natural additives in pipeline transportation has gained significant attention in recent years due to their potential to enhance the stability and rheology of the suspension. In this study, the dispersing and stabilizing properties of the saponin extracted from the fruits of Sapindus laurifolia are examined in the pipeline transportation of limestone. The physicochemical, morphological, and flow characteristics of limestone samples less than 75 μm are determined. The rheological behaviors of the suspension have been examined by varying the shear rate, solid, and dispersion concentrations. The critical micelle concentration of the dispersant was determined to be 1.8 wt%. In the tested concentration ranges of 40–70%, the Hershel–Bulkley model best matched the data. When the surfactant was added to the suspension, the water's surface tension was lowered, increasing the wettability of the limestone particles and decreasing particle-particle contact. Increases in zeta potential measurements confirmed that the steric component primarily stabilizes limestone water suspension. Finally, the dispersant's economic impact was studied depending on slurry head loss and specific energy consumption. [ABSTRACT FROM AUTHOR]

This study examined the combined effect of torrefaction and microwave absorbers on improving biomass thermochemical characteristics and grindability for heat, power, and value-added products. Camelina straw in two grinds, ground (6.4 mm screen size) and chopped with biochar addition (0%, 10% and 20%), was torrefied in a bench-scale microwave reactor at torrefaction temperatures of 250 °C and 300 °C with residence times of 10, 15 and 20 min under inert conditions and nitrogen-activated. After torrefaction, the geometric mean particle and size distribution, moisture content, ash content, bulk and particle densities were determined, and the grinding performance values of torrefied ground and chopped with and without biochar were determined and compared with the raw camelina straw. The results showed that the geometric diameter decreased after torrefaction in both grinds. The specific energy required for grinding torrefied biomass decreased significantly with biochar addition, longer residence times, and increased torrefaction temperatures. Torrefied ground camelina straw with biochar after grinding had the lowest grinding energy of 34.30 kJ at 300 °C/20 min. The surface morphology by confocal laser scanning microscopy of torrefied camelina straw particles indicated that biochar addition (>10%) and a torrefaction temperature at 250 °C can create profound surface distortion, and beyond 300 °C, colossal surface damage and carbonized weight fractions were produced. [ABSTRACT FROM AUTHOR]

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.

Energy recovery devices can reduce the specific energy consumption and operation cost of reverse osmosis desalination systems, which is an important core energy-saving equipment. In this paper, four combined processes were proposed, including turbine-free single-stage, single-turbine single-stage, dual-turbine two-stage, and single-turbine inter-stage pressurization for reverse osmosis seawater desalination systems, whilst ensuring the same influent flow rate and recovery rate. The whole process routes and equipment selection were also studied. To evaluate the performance of the combined process, the specific energy consumption ratios were analyzed with two different energy consumption ratio analysis methods. The results showed that energy recovery technology can reduce system-specific energy consumption. Optimizing the combination of turbine energy recovery devices, especially the combination process of dual-turbine double-stage desalination system and single-turbine inter-stage pressurized desalination system can significantly reduce the specific energy consumption and overall cost of the system.

This study examined the combined effect of torrefaction and microwave absorbers on improving biomass thermochemical characteristics and grindability for heat, power, and value-added products. Camelina straw in two grinds, ground (6.4 mm screen size) and chopped with biochar addition (0%, 10% and 20%), was torrefied in a bench-scale microwave reactor at torrefaction temperatures of 250 °C and 300 °C with residence times of 10, 15 and 20 min under inert conditions and nitrogen-activated. After torrefaction, the geometric mean particle and size distribution, moisture content, ash content, bulk and particle densities were determined, and the grinding performance values of torrefied ground and chopped with and without biochar were determined and compared with the raw camelina straw. The results showed that the geometric diameter decreased after torrefaction in both grinds. The specific energy required for grinding torrefied biomass decreased significantly with biochar addition, longer residence times, and increased torrefaction temperatures. Torrefied ground camelina straw with biochar after grinding had the lowest grinding energy of 34.30 kJ at 300 °C/20 min. The surface morphology by confocal laser scanning microscopy of torrefied camelina straw particles indicated that biochar addition (>10%) and a torrefaction temperature at 250 °C can create profound surface distortion, and beyond 300 °C, colossal surface damage and carbonized weight fractions were produced.

Based on the current research, the hybridization of desalination technologies has proven to be an effective method of enhancing system performance, minimizing energy consumption, and reducing product water cost. This study focuses on a hybrid MED-RO desalination plant in a large coastal steel enterprise situated in Northeast Asia, China. A comparative analysis of distinct hybrid systems was undertaken, followed by the selection of an optimal process route that aligns with the site-specific conditions and the requirements of downstream freshwater users. To investigate the influences of feed and operational factors on RO process performance, mathematical models were developed for water balance, RO module performance, energy consumption, and economic indicators. Furthermore, according to actual plant conditions, the software simulation and cost benefit analysis were performed for the hybrid desalination system sensitivity analysis and optimization. The outcomes including permeate qualities, concentrate salinity, specific energy consumption, and economic indicators were analyzed to achieve the optimal hybrid system design and operational parameters. Finally, through engineering application of the optimized parameters, the hybrid system performance underwent notable improvement. The calculations reveal that, in comparison to standalone or alternative hybrid systems, this hybrid system exhibits superior energy-saving efficiency, lower operational costs, and reduced carbon emissions. Specifically, the system achieves a recovery rate of approximately 54.22 %, with an average product water cost of 0.5582 US$/m³. Additionally, the energy consumption is 1.015 kgce/m³, translating to an equivalent carbon emission of 2.49 kg/m³.

Energy saving and consumption reduction is one of the current important research in the field of green and sustainable manufacturing. Products or components containing variable curvature contouring are widely used in the automotive, medical, aerospace, and mold industries, while there is a lack of methods to model the energy consumption ratio for variable curvature contouring and improve its energy efficiency. A method for modeling the specific energy consumption of variable curvature contouring and energy consumption optimization is proposed for this problem. Firstly, the components of energy consumption in processing of the CNC machine tool machining are analyzed, and the relationship between curvature characteristics and material removal rate is investigated from the geometric perspective. Secondly, orthogonal experiments with different curvatures of straight lines, convex arcs, and concave arcs are designed to collect energy consumption data. Based on the experimental data, the Dueling Deep Q-Network optimization support vector regression (Dueling DQN-SVR) was used to establish the specific energy consumption model considering the curvature. Finally, a multi-objective optimization model is constructed when considering specific energy consumption, efficiency, and quality, and the Pareto solution set is solved using a multi-objective Gray Wolf optimization algorithm (MOGWO). The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method was used to select the optimal combination of machining parameters. The experimental results show that the accuracy of the established model is more than 95%. The method improved energy efficiency by more than 7.82% and efficiency by more than 1.128%. These research results are of great theoretical and practical significance for achieving energy-efficient variable curvature contour machining. [ABSTRACT FROM AUTHOR]

This study developed dried shiitake mushrooms through belt-conveyor combined microwave-hot air (MWHAB) drying, comparing it with hot air (HA) drying. MWHAB drying, with microwave powers ranging from 300 W to 600 W at 65 °C, was contrasted with HA drying at the same temperature. Both blanched and unblanched samples were dried to a final moisture content of 11.1% (d.b.). The research evaluated drying kinetics, specific energy consumption (SEC), and various quality aspects, including color, shrinkage, rehydration, texture, and microstructure. Results showed that blanched samples dried with MWHAB at 600 W significantly reduced drying times and SEC by 76.9% and 77.3%, respectively, compared to HA drying. Dried MWHAB products exhibited lower shrinkage and hardness but higher rehydration, larger pore sizes, and void area fraction than HA. Although no significant color differences were observed, MWHAB drying at 600 W yielded lower values for shrinkage and hardness, and higher values for rehydration, void area fraction, and larger pore sizes than other cases. Additionally, unblanched dried samples displayed reduced shrinkage and hardness but increased color values, rehydration, larger pore sizes, and void area fraction compared to blanched samples. Optimal shiitake mushroom production is recommended using unblanched samples dried with MWHAB at 600 W microwave power. [ABSTRACT FROM AUTHOR]

Due to rapid development of cities, number of municipal wastewater treatment plants (WWTP) has faced drastic growth in recent decades. Reviewing the literature indicates that WWTPs in urban areas are one of the essential energy consumers, and it is necessary to evaluate their energy consumption. In Tehran, the capital of Iran, the number of WWTPs has increased to meet the demands of its increasing population. Yet, the energy consumption of these WWTPs in Tehran has not been thoroughly examined. This research aims to measure and provide the specific energy consumption of Tehran WWTPs and bridge the research gap by providing precise measurements for three key performance indicators (KPIs): energy consumption per influent volume (kWh/m³), per population-equivalent (kWh/PE-year), and per kilogram of Chemical Oxygen Demand removed (kWh/kg COD). The South Tehran Wastewater Treatment Plant (STWWTP), the largest WWTP in Tehran, demonstrated highest energy efficiency with consumption rates of 0.21 kWh/m³ for influent volume, 16.75 kWh/PE-year, and 0.48 kWh/kg COD removed. Furthermore, the smallscale WWTPs of Tehran showed a significant variation in specific energy consumption. Zargandeh Wastewater Treatment Plant (ZWWTP) represented the poorest efficiency by consuming 96.34 kWh for each person under its service and 3.66 kWh per kg COD removed. In contrast, Ekbatan Wastewater Treatment Plant (EWWTP), among the small-scale WWTPs, demonstrated great energy efficiency with consumption rates of 33.15 kWh per capita and 0.52 kWh/m³. However, this great variation in energy consumption of Tehran WWTPs needs further investigation, and strategies for improving the energy efficiency of these WWTPs are required. [ABSTRACT FROM AUTHOR]

This study investigates how temperature and forward osmosis (FO) membrane properties, such as water permeability (A), solute permeability (B), and structural parameter (S), affect the specific energy consumption (SEC) of forward osmosis-reverse osmosis system. The results show that further SEC reduction beyond the water permeability of 3 LMH bar-1 is limited owing to high concentration polarization (CP). Increasing S by 10-fold increases FO recovery by 177.6%, causing SEC decreases by 33.6%. However, membrane with smaller S also increases external CP. To reduce SEC, future work should emphasize mixing strategies to reduce external CP. Furthermore, increasing the temperature from 10 to 40 °C can reduce SEC by 14.3%, highlighting the energy-saving potential of temperature-elevated systems. The factorial design indicates that at a lower temperature, increasing A and decreasing S have a more significant impact on reducing SEC. This underlines the importance of developing advanced FO membranes, particularly for lower-temperature processes. [ABSTRACT FROM AUTHOR]

In the current study, four drying methods, namely microwave (MD), vacuum (VD), hot air (HAD), and freeze drying (FD), were compared for drying of Indian borage (Plectranthus amboinicus) leaves for optimum energy consumption and bioactive compounds' retention. Effective moisture diffusivity for MD was about 100 times more than that of HAD and VD. MD at 600 W showed minimum specific energy consumption (4.04 kWh/kg), proving the most suitable drying condition. Moreover, it showed desirable energy values in terms of maximum specific moisture extraction rate (0.265 kg moisture/kWh) and maximum drying efficiency (15.85%). Bioactive compounds' retention in terms of phenols, antioxidants, and flavonoids was better in MD, followed by FD. Mathematical modeling of drying kinetics data revealed proper fitting of three drying models, namely, Aghbashlo, Modified Page‐II, and Page model, for explaining the drying behavior of Indian borage leaves. Multivariate characterization using principal component analysis revealed that FD and MD had a strong effect on bioactive compounds' retention, while VD and HAD showed least effect. Hence, based on optimum energy utilization and bioactive compounds' retention, MD at 600 W was selected for efficient drying of Indian borage leaves. Practical applications: Drying of Indian borage leaves using microwave drying (MD) resulted in quicker drying with retention of bioactive compounds and color of dried leaves. The energy aspects were also favorable for industrial scale‐up. With due consideration to capacity enhancement in MD, it can prove to be a promising source of drying for culinary, medicinal, and aromatic plants. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study proposes a feasible solution for boil-off gas (BOG) treatment to facilitate NH3 fuel use by ocean-going ships, which is currently considered an alternative fuel for ships. Two systems were designed and analyzed for BOG in IMO Type-A NH3 fuel storage tanks for 14,000 TEU container ships. First, BOG lost inside the storage tank minimized economic losses through the onboard re-liquefaction system. The total energy consumed by the system to process NH3 gas generated in the fuel tank at 232.4 kg/h was 51.9 kW, and the specific energy consumption (SEC) was 0.223 kWh/kg. Second, NH3 was supplied to the direct Low-Pressure Selective Catalytic Reduction (LP-SCR) system to treat marine pollutants generated by combustion engines. The feasible design point was determined by calculating the NH3 feed flow rate using three methodologies. The energy consumed by the direct LP-SCR system was 3.89 and 2.39 kW, and the SEC was 0.0144 at 0.0167 kWh/kg at 100% and 25% load, respectively. The feasibility was indicated via economic analysis. Depending on the life cycle cost, the competitiveness of the re-liquefaction system depends on the price of NH3, where a higher price yields a more economical solution. In conclusion, the direct LP-SCR system has a low overall cost because of its low energy consumption when supplying NH3 and its reduced amount of core equipment. [ABSTRACT FROM AUTHOR]

A global manufacturing community is dedicatedly striving to implement the concept of NetZero in precision cutting of difficult-to-machine materials, specifically, Inconel 617 (IN617) with due consideration to environmental protocols. The fast strain hardening issue of the said alloy during conventional processing rationalizes the application of electric discharge machining (EDM). However, EDM has been criticized for its high energy consumption and limited cutting efficiency. Moreover, conventional dielectric (kerosene) employed in EDM has drastic environmental and operator health concerns. To address the abovementioned issues, waste cooking oil (WCO) has been employed in this study which enhances the reusability of resources and minimizes the cost of the dielectric. Making the process sustainable is imperative along with continuously escalating scarcity of engineering resources. Therefore, the potential of shallow and deep cryogenically treated electrodes (SCT and DCT) has been comprehensively examined against nanofilled WCO to achieve the aforementioned objective. Three different concentrations of powder (Cp) and surfactant (Cs) to uplift the machining responses are investigated through a detailed parametric experimental design. Core machining factors such as material removal rate (MRR), surface roughness (SR), and specific energy consumption (SEC) are examined through optical and electron microscopy studies and 3D surface profilometry. Hereafter, machining factors are modelled using the artificial neural network (ANN) technique. An exceptional improvement of 80%, 25.3%, and 75.16% has been achieved in MRR, SR, and SEC respectively using nanopowder-mixed WCO against SCT brass compared to the responses' values obtained against conventionally used kerosene. Furthermore, compared to kerosene, the maximum CO2 reduction of 79.97 ± 11.2% is achieved with WCO. [ABSTRACT FROM AUTHOR]

Influences of drying air temperatures on drying time, specific energy consumption as well as product quality of culture asparagus were investigated in hot-air drying. The drying properties of asparagus samples were performed in a laboratory scale convection dryer at three different temperatures. The drying times of asparagus samples were found as 1200, 630 and 510 min for 50, 60 and 70 °C, respectively. In regard to the data obtained, Midilli et al. model is superior to other models to describe drying behavior of asparagus samples. The effective moisture diffusivity values of asparagus samples were calculated between 6.32 ⋅ 10-9-1.62 ⋅ 10-8 m²/s and the activation energy was estimated as 43.59 kJ/mol. The highest rehydration content and the least total color change were found in asparagus slices dried at 50 °C. Energy consumption values for asparagus samples dried at 50, 60 and 70 °C temperatures were obtained as 10.14, 5.32 and 4.31 kWh, respectively. In terms of energy consumption values, the best efficiency among all drying temperatures was obtained at 70 °C. It has been determined that the specific energy consumption decreased with increasing temperature. [ABSTRACT FROM AUTHOR]

Sun drying is the most common technique used to dry various food products due to its economic convenience. However, it is not effective owing to its unreliable nature leading to microbial deterioration and aflatoxin contamination of food. In Tanzania, about 1.3 million tonnes of maize bran are at risk of deterioration annually due to improper drying. The aim of this study was to design, fabricate and test an efficient small-scale flash dryer for maize bran. Using principles of material and energy balance, a small-scale flash dryer with a throughput of 500 kg of dry product per hour was designed resulting in a nominal diameter of 387 mm and a drying length of 20 m. Design calculations and drawings were done using MS Excel 2021 and SolidWorks 2018 respectively. Empirical procedures were used to fabricate and test the dryer. The material of construction used in the flash duct was food grade (stainless steel, SS 201). A fuel blend of Waste Engine Oil (WEO) and diesel (85%-15%) was used with a novel heavy oil burner. It was observed that at an inlet air temperature of 150 °C and air velocity of 12 m/s, moist maize bran was dried from 37% to 10% w.b. The fabricated flash dryer's energy efficiency, specific energy consumption, and specific energy utilization are 74%, 3.4 MJ/kg water evaporated, and 1.71 MJ/kg dry maize bran respectively. It was concluded that the fabricated small-scale flash dryer displayed improved energy performance compared to others presented in literature. Better instrumentation was recommended for feedback control on burner operation and process monitoring which further enhances the performance of the fabricated small-scale flash dryer. [ABSTRACT FROM AUTHOR]

In grinding processes using hammer mills, the configuration, number and speed of hammers are some of the main factors that can affect system performance. This paper aims to investigate the effects of hammer configurations in terms of specific energy consumption (SEC), grinding mass efficiency, and productivity. These effects were studied theoretically on the basis of classical grinding laws and experimentally with four different hammer configurations. From theoretical studies, a decreasing power model of SEC versus hammer configurations was developed, which was then validated with a determination coefficient of 0.99 in experiments using a 2 HP-DC hammer mill. The good agreement between theoretical and experimental results confirms that the specific energy consumption and the productivity are directly dependent on hammer configurations, but the effects are not significant for grinding mass efficiency. [ABSTRACT FROM AUTHOR]

This study explores the existing literature on specific energy consumption (SEC) use for paddy drying and consolidates all relevant data for comparisons across technologies. Energy consumption data for a range of drying technologies are consolidated from published literature and normalized to enable comparison. A large proportion of the source data are generated from operational performance in industrial or laboratory settings, while the remainder is derived from computer simulations. The SEC of paddy drying is driven primarily by technology type; however, operational factors (such as the system size, temperature, and airflow) and external factors (such as the local climate and paddy moisture content) also heavily influence system energy use. The results of our analysis show that the industrial drying technologies explored in this study have an average SEC of 5.57 ± 2.21 MJ/kg, significantly lower than the 20.87 ± 14.97 MJ/kg observed in a laboratory setting, which can potentially be attributed to differences in processing capacity. Multi-stage drying typically has higher energy efficiency when tempering stages are incorporated. The self-circulating design of some drying systems may provide additional opportunities for heat exchange, leading to efficient drying performance without the need for a separate tempering stage. Beyond traditional methods, we have observed a notable shift towards solar-assisted and infrared drying technologies in laboratory settings, reflecting an increasing interest in sustainable and efficient drying solutions. In summary, this review consolidates SEC data for rice drying technologies, analyzes the energy intensity and performance of each drying technology, and identifies data gaps that might be addressed in future research. [ABSTRACT FROM AUTHOR]

Drying is an important means to maintain the quality of peanut pods and reduce the risk of mildew. Microwave hot air combined drying is renowned for its efficacy, low-energy consumption, and superior processing quality, rendering it suitable for peanut pod drying. However, its efficacy hinges greatly on various parameters. To enhance drying efficiency and quality, the drying kinetics of peanut pods using microwave hot air combined drying equipment were investigated. Varying microwave power (1.2 kW, 2.4 kW, 3.6 kW), hot air temperature (30 °C, 35 °C, 40 °C, 45 °C), air velocity (0.4 m/s, 0.7 m/s, 1 m/s), and microwave radiation time (4 min, 6 min) were examined. Results indicated a decline in drying time, moisture ratio, and drying rate with increasing microwave power, hot air temperature, air velocity, and microwave radiation time. Peroxide and acid values complied with national standards. The Verma model exhibited optimal fitting. At 45 °C, peanut pod moisture diffusion coefficient was 3.022 × 10−9 m2 s−1, specific energy consumption at 30 °C was 5302 kJ/kg, and thermal efficiency was 42.6 %. The synergistic drying of peanut pods by microwave and hot air has a high moisture diffusion coefficient and thermal efficiency. The kinetic and energy analysis of the drying process can furnish some theoretical foundation for subsequent microwave hot air drying and equipment parameter adjustment.

Advanced airborne equipment liquid cooling system presents the development trend of multiple pumps in parallel, centralised heat dissipation and high efficiency circulation, but this type of system has the characteristics of many variable parameters and strong non-linearity, which makes the system operation and control become extraordinarily complex, posing a serious challenge to the system performance. Although some progress has been made in the current optimization of liquid cooling system performance, there are still gaps such as insufficient consideration of the multi-objective optimization problem and limited optimization effect. To fill this research gap, this study takes minimum specific energy consumption, minimum flow deviation and minimum impeller load as the optimization objectives, establishment of multi-objective optimization model for liquid-cooled power unit, the optimal solution set of the Pareto model is solved using the multi-objective grey wolf optimization algorithm (MOGWO), and the optimal solution set is substituted for the optimal solution, and the evaluation indexes are designed in combination with the actual working conditions to obtain the optimal schedule. By example analysis, the optimized system under variable operating conditions, the impeller load and specific energy consumption decreased by 16.88% and 3.64% respectively, while the rise in flow deviation was controlled within 0.76%. The newly established optimisation model effectively mitigates potential safety hazards during system operation. Finally, by combining all the indicators, three scheduling options are provided under variable operating conditions, focusing on reliability and economy, overall balance and high-precision flow, respectively, in order to adapt to the diversified requirements of different operating environments.

In this research, I established an energy benchmark for the pulp and paper industry of Vietnam. I, therefore, focus on three major paper product families, including packaging paper, printing and writing paper, and tissue paper. In this research, I use specific energy consumption (SEC) as the energy performance indicator (EnPI) for computing energy benchmarks for the main sub-sectors in the pulp and paper industry of Vietnam. The factories in the pulp and paper industry of Vietnam are divided into three production scales, and the energy benchmarks are specified by production scales. Energy surveys and energy audits have been used to calculate energy benchmarks. Here, I establish the energy benchmark for the main sub-sectors in the pulp and paper industry of Vietnam according to the three production scales. I also estimate the energy saving potential for the pulp and paper industry of Vietnam based on surveying and auditing results.

AbstractThis research was set out to evaluate the specific energy consumption (SEC) in drying African oil bean seed using convective hot air and microwave oven dryers. The process parameters investigated in thin-layer drying were temperature (40, 50, 60, 70 °C), microwave power (450, 720, 900 W), slice thickness (2, 3, 5 mm) and treatment (untreated (UT), brine pretreated (BT) and sucrose pretreated (ST)). Response surface methodology (RSM) was used to evaluate the effect of oven temperature, microwave power, slice thickness, and treatment on the SEC of African oil bean seed. The result revealed that the SEC for African oil bean seed ranged from 21.12 to 57.33 k Wh kg−1 and 90.76 to 261.23 k Wh kg−1 for microwave and oven drying, respectively. The study also found that the SEC decreases with increase in slice thickness in both microwave and oven dryer. The microwave oven method reduced SEC of African oil bean seed by 22% compared to convective hot air oven drying method. The optimum SEC was obtained at 4 mm material thickness, 53.57 °C hot air oven temperature and 814.32 W microwave power. Among the treatments, BT sample is comparatively the best treatment for AOB in order to save drying energy consumption.

This article describes elements of the know-how of using carbon electrodes produced using the technology of molding around a rod when smelting silicon metal. Application of our know-how will dramatically increase the competitiveness of silicon metal production. Experts’ concerns regarding the use of such electrodes were that such electrodes have a through axial hole. This significantly reduces the mechanical strength of such electrodes, which can presumably lead to problems associated with the breakage of the working side of the electrode, which is immersed in the smelting space of the furnace under the charge layer. Industrial testing of such electrodes was carried out in a 30 MVA furnace of “Tau-Ken Temir” LLP. During testing, we used an approach previously developed by our team for working with a furnace in the process of smelting silicon metal. In particular, we used an interval between top treatments of about 30 min and adhered to the principles of balanced smelting, i.e., provided a balance between the intensity of the uniform supply of the charge into the furnace and the current active electrical power. Industrial testing carried out over four weeks confirmed the stability of the operation of cheaper carbon electrodes with a through axial hole. The recovery of silicon into finished products was also improved to 88–89% and the specific energy consumption was reduced to 11.2–12.1 MWh/t of silicon metal from the initial value 14,752 MWh/t. Thus, we received additional evidence for the effectiveness of our approach in furnace operating compared to an approach based on the ultimate provision of gas and permeability of the furnace top due to excessively intense processing of the top and an uncontrolled, uneven supply of charge to the furnace.

The awareness of energy consumption is gaining much more attention in manufacturing due to its economic and sustainability benefits. Reducing energy consumption in advanced manufacturing processes, like directed energy deposition (DED) manufacturing, is critical for Industry 4.0 and the forthcoming Industry 5.0 since it allows for more economical, sustainable, and environmentally friendly manufacturing approaches. An energy consumption model is needed for quantifying the consumption and predicting the impact of various process parameters in manufacturing. This paper aims to develop an energy consumption model for DED-based hybrid additive manufacturing (HAM) for an Inconel 718 part. The specific energy consumption (SEC) is used while developing the energy consumption of the product manufacturing lifecycle. This study focuses on the analysis to investigate three significant factors (scanning speed, laser power, and feed rate), their interactions' effects, and whether they have a significant effect on energy consumption. The results suggest that all the factors have a strong influence, but their interaction effects have a weak influence on the energy consumption for HAM. Among the three process parameters, it is found that laser power has the most significant effect on energy consumption. Again, based on the regression analysis, this study also recommends high scanning speed while the laser power and feed rate should be low. Also, idle time has significant energy consumption during the whole HAM process. [ABSTRACT FROM AUTHOR]

The present study demonstrates a comprehensive characterisation of an Indian iron ore sample to investigate the effect of blending coarse particles with fine particulate slurry on the rheology, slurryability, and stability of iron ore suspension. Various bench-scale tests are carried out to determine iron ore samples' physico-chemical, morphological, and flow characteristics. The iron ore samples with three distinct particle size ranges (< 38, 38–75, 75–106 µm) are used to prepare eight different bi-modal slurry samples. The rheological characteristics of the slurry are investigated at a shear rate range between 50 and 600 1/s, and regression analysis is performed to evaluate the nature of the slurry. Finally, the best particle size distribution is evaluated based on critical parameters such as apparent viscosity, settling characteristics, pressure drop, and specific energy consumption. The optimal proportion of coarse particles (38–75 µm) blending in the slurry suspension of fine particulate is observed at 40% (by weight), while in the case of the coarse particle (75–106 µm), it is 30% (by weight). Maximum pressure drop reduction recorded for the optimal proportion bi-modal samples I7 and I10 at 40, 50, 60, 70, 75, and 80% concentrations is 57.6, 56.81, 55.2, 52.45, 49.31, 46.3%, and 57.98, 59.18, 56.2, 54.74, 50.86, 48.15%, respectively. In contrast to uni-modal samples, the specified bi-modal samples with an optimal particle size distribution showed significantly lower yield stress, viscosity and enhanced solids loading in the slurry. [ABSTRACT FROM AUTHOR]

In fact, current water supplies due to natural constraints or lack of infrastructure (or both) cannot be provided in a sustainable manner for all increasing and competing uses (e.g. residential, industrial, agricultural). While promoting Penghu's low-carbon islands, in a water-scarce environment, it is the motivation of this research to take into account the development of water resources and lower energy consumption costs. The seawater desalination plant water production technology is improved, the cost of water production is reduced. This research uses a genetic algorithm (GA) to optimize the recovery rate to solve the minimum Specific energy consumption (SEC) value, and then, according to the required water production, the optimal flow rate of raw seawater of the high-pressure pump is obtained, so as to minimize the energy consumption of the reverse osmosis (RO) system. The energy recovery device has a great effect on reducing the energy consumption of the RO system, and it can be seen from the results that the higher efficiency does greatly reduce the energy consumption of the SEC and water production under the different energy recovery device efficiency. Calculated using genetic algorithms, and the SEC is 3.275 and the recovery rate is 45.1%, and the water production energy consumption is 2.35 kWh/m3. Scheme B changed the efficiency of the energy recovery unit to 97.22%, resulting in a SEC of 1.819 and a recovery rate of 25.3%, and a water production energy consumption of 1.31 kWh/m3. Finally, challenges and research gaps are also proposed. [ABSTRACT FROM AUTHOR]

Cryogenic supercritical hydrogen storage technology is a high-density physical hydrogen storage method, which is a highly promising hydrogen storage approach. However, existing research has mainly focused on the development of storage devices for cryogenic supercritical hydrogen, with limited research on the cooling process of supercritical hydrogen. Therefore, a novel cooling process for cryogenic supercritical hydrogen production based on helium expansion cycle with liquid nitrogen (LN 2) pre-cooling is proposed in this paper. In this process, after being compressed and cooled in multiple stages, the feed hydrogen is pre-cooled by LN 2. Then, cryogenic supercritical hydrogen (10 MPa, −235.15 °C, 63.36 g/L) is obtained by helium multi-stage expansion refrigeration. The process is simulated by Aspen HYSYS and optimized by genetic algorithm (GA) to obtain lower specific energy consumption (SEC). Thermodynamic analyses are conducted to evaluate the process. And compared with the conventional hydrogen liquefaction process, the results show that the proposed process is reasonable and superior. The SEC 0 , figure of merit (FOM), and the total exergy loss of the system are 5.432 kWh/kg H2 , 43.88%, and 289.69 kW respectively. This study indicates that the proposed process has significant implications for the hydrogen industry and provides valuable information for cryogenic supercritical hydrogen storage systems. • A novel high-density cryogenic supercritical hydrogen storage system is proposed. • Twelve key variables in the process are optimized to reduce the energy consumption. • The process has higher exergy efficiency than conventional LH 2 plants. • The volume storage density of hydrogen can reach 63.36 kg/m3 in the system. [ABSTRACT FROM AUTHOR]

Hydrotransport is increasingly a popular technology due to its low specific energy consumption and nonpolluting nature. The current work presents a thorough characterization of a limestone sample to explore the influence of blending medium and coarse particles with fine particulate slurry on the rheology, slurryability, and stability of a limestone water suspension. Various bench-scale studies are performed to identify the physicochemical, morphological, and flow features of limestone samples. Eight separate bi-modal slurry samples are prepared using limestone materials with three unique particle size ranges (53, 53–75, and 75–106 µm). The rheological properties of the slurry are tested at shear rates ranging from 50 to 500 1/s, and regression analysis is used to determine the nature of the slurry. The solid concentration of the suspension sample ranges between 10 and 70% with a flow velocity range of 0.25–1.5 m/s through a 100 mm diameter pipeline. Finally, essential criteria such as apparent viscosity, settling properties, pressure drop, and specific energy consumption are used to determine the optimal particle size distribution. The ideal proportion of medium particles (53–75 µm) mixing in the fine particulate slurry suspension is 40%, while the fraction of coarse particles (75–106 µm) is 30% (by weight). [ABSTRACT FROM AUTHOR]

Fluidized bed dryer is used to dry the silica sand used in core production in the casting industry. In this study, a heat recovery unit was designed in a drying system using waste heat recovery and the effects of specific energy consumption on heat recovery were investigated by performing energy, environmental and economic analysis. In this context, it is aimed to increase the drying efficiency, reduce carbon emissions and the effects of global warming with the heat recovery unit used in the preheating of the drying air blown by the fan. According to the results, a reduction of 12.815 m3/h in natural gas consumption and 0.032 tons CO2/h in carbon emissions will occur if the design with the 1st stage drying air preheating heat recovery unit is changed from the current design. If the current system is changed to a system with heat recovery unit, 1,428,753.81 TL can be saved annually and the payback period of the heat recovery unit was calculated 0.66 years. A reduction of 4.34 m3/h in natural gas consumption and 0.011 tons CO2/h in carbon emissions will occur if the design is changed from the current design to the design where the 2st stage in-plant water heating heat recovery unit. Thus, if the current system is changed to a system with heat recovery unit, 1,912,602,548 TL can be saved annually, and the payback period is calculated as 0.16 years. When this design is implemented, a more economical and sustainable drying system will be bringed to life. [ABSTRACT FROM AUTHOR]

In this study, a new method for the LNG has been proposed based on the SMR process. In the proposed process, an ORC is added to the conventional SMR process and the BOG is used as a coolant in the main heat exchanger. ASPEN HYSYS software utilizing the Peng–Robinson equation of state is used to simulate the SMR and SMR-ORC. The specific energy consumption, total exergy efficiency, and carbon dioxide emissions of the proposed method are compared with the conventional SMR process. Finally, an economic evaluation was performed on both processes. The simulation results showed that in the conventional process the total exergy efficiency and specific energy consumption are 34% and 647 kWh ton , respectively, while in the proposed process the total exergy efficiency has reached 39% and the energy consumption is reduced to 472 kWh ton . Also, the environmental assessment of carbon dioxide emissions from the production of electrical energy required by pumps and compressors showed that the proposed process has 28.51% less carbon dioxide emissions than the conventional SMR method. [ABSTRACT FROM AUTHOR]

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This research was set out to evaluate the specific energy consumption (SEC) in drying African oil bean seed using convective hot air and microwave oven dryers. The process parameters investigated in thin-layer drying were temperature (40, 50, 60, 70 °C), microwave power (450, 720, 900 W), slice thickness (2, 3, 5 mm) and treatment (untreated (UT), brine pretreated (BT) and sucrose pretreated (ST)). Response surface methodology (RSM) was used to evaluate the effect of oven temperature, microwave power, slice thickness, and treatment on the SEC of African oil bean seed. The result revealed that the SEC for African oil bean seed ranged from 21.12 to 57.33 k Wh kg−1 and 90.76 to 261.23 k Wh kg−1 for microwave and oven drying, respectively. The study also found that the SEC decreases with increase in slice thickness in both microwave and oven dryer. The microwave oven method reduced SEC of African oil bean seed by 22% compared to convective hot air oven drying method. The optimum SEC was obtained at 4 mm material thickness, 53.57 °C hot air oven temperature and 814.32 W microwave power. Among the treatments, BT sample is comparatively the best treatment for AOB in order to save drying energy consumption. [ABSTRACT FROM AUTHOR]

In the realm of petrochemical operations, persistent efforts have been made to curtail specific energy consumption; however, certain heat sources continue to be underutilized. This paper investigates the condition of a Lurgi methanol plant to identify process streams with enough wasted heat that have the potential to produce electricity. After a thorough analysis, one particular zone is identified where an air cooler package and seawater exchanger are used to decrease the temperature of crude methanol vapor. To harness this untapped heat for electricity generation, an organic Rankine cycle (ORC) is proposed. In the quest for efficient electricity production, three distinct working fluids-dry (R600a), wet (R134a), and isentropic (R11)- are scrutinized to compare their performance in generating electricity within the ORC system. In addition, the maximum amount of electricity that can be generated from this waste heat recovery (WHR) project is determined and optimized using a multi-objective optimization method. By leveraging genetic algorithms, the system's exergy is enhanced while minimizing costs. A comprehensive economic comparison is conducted using probability analysis to evaluate each system's financial viability. The results show that dry and isentropic working fluids yield the best results for electricity production, generating approximately 9–10 MW. The return on investment (ROI) for these working fluids is also nearly similar, at 16 %. Among the chosen working fluids, R600a is selected as the superior option due to its lower outlet temperature for crude methanol. Additionally, because the cooling water flow for the condenser of the ORC is identified as a limitation in the current petrochemical plant, a new optimization is conducted with a constraint on the flow of cooling water, aiming for approximately 3000 tons/h. The results show that the proposed WHR-ORC system can generate a maximum of approximately 7.5 MW net electricity in the studied petrochemical plant, while also reducing CO2 emissions by up to 40,000 tons per year. The innovative methodology showcased in this research underscores its economic viability, paving the way for heightened energy efficiency and environmentally conscious methanol production practices.

Fresh ginseng has a high moisture content and is easy to be deteriorated, thus an effective drying method is needed. Infrared drying is known as low energy consumption, and high heat transfer, thus the far infrared (FIR) and near infrared (NIR) drying characteristics of ginseng were investigated and compared. Influences of infrared temperature, radiation distance, and slice thickness on the drying kinetics, specific energy consumption, color change and rehydration ratio were analyzed. Results indicated that the drying rate of ginseng increased with increasing infrared temperature and decreasing radiation distance and slice thickness. The drying time under FIR was shortened by 33.3%, 25% and 20% at 40 °C, 50 °C, 60 °C compared to that under NIR, indicating that the drying efficiency of FIR was superior to that of NIR and with the decrease of temperature, this improvement became more obvious. The specific energy consumption can be reduced by up to 40% under FIR and the infrared drying was much more energy-efficient than hot air drying, with an energy reduction by up to 51.1%. Optimization of FIR drying showed that the optimal conditions were at a drying temperature of 50 °C, a slice thickness of 2 mm and a radiation distance of the 4th layer.

BACKGROUND AND OBJECTIVES: Energy efficiency plays a crucial role in the success and sustainability of desalination technologies. Energy considerations are intricately linked with every aspect of planning, management, and operation in water desalination. This study aims to evaluate and enhance energy requirements, energy efficiency, and the economic feasibility of the Hashemite University photovoltaic brackish water reverse osmosis desalination plant at Hashemite University.METHODS: This study’s aims were achieved by conducting an energy audit and detailed assessment to identify the energy efficiency considerations that should be integrated into the facility’s planning, management, and operation strategies. To ensure accurate and reliable data collection and enable a comprehensive analysis of the plant’s energy performance, portable energy analyzers and loggers were employed to measure energy consumption, and measurements and verification techniques were recommended and implemented to establish the required baseline. A regression model was utilized to determine the potential energy savings resulting from energy conservation measures. This involved determining the expected savings by calculating the area between two curves: the new actual consumption of the brackish water reverse osmosis plant after implementing energy conservation measures and the curve generated by the model representing the usual consumption in the absence of energy conservation measures.FINDINGS: This study underscores the challenges faced by desalination, particularly regarding intensive energy consumption. It also presents innovative ways to achieve sustainability by emphasizing energy efficiency, integrating renewable energy, and advocating for a holistic water management approach. It was determined that the maximum specific energy consumption of the Hashemite University photovoltaic brackish water reverse osmosis plant was 0.625 kilowatts per cubic meter. This reflects the actual consumption and energy performance of the plant, which was found to be 192 percent more efficient than the estimated specific energy and 144 percent more efficient than the calculated specific energy. No energy conservation measures were implemented at this stage, as the plant was already operating efficiently. The measured data shall be considered as a baseline for future investigations and monitoring and evaluation of the plant. Many challenges were identified during the current work, including the low quality of raw water and minimal demand for freshwater, which resulted in lower operation hours outside of sun peak hours, while the direct utilization of photovoltaic energy is recommended.CONCLUSION: Renewable energy and energy recovery were recognized as potential sources for energy savings to achieve sustainable and long-term feasible operation and cost recovery at the Hashemite University photovoltaic brackish water reverse osmosis plant. The feasibility of the plant showed a fast payback period of up to 1.1 years. Utilizing clean solar photovoltaic energy to power the brackish water reverse osmosis plant led to a considerable reduction of greenhouse gases (mainly carbon dioxide). The estimated amount of carbon dioxide reduction during the project’s lifetime was 1,289,600 kilograms. The integration of solar energy showed promise for further enhancing energy efficiency and sustainability. This study contributes to making the desalination sector more environmentally friendly and economically viable, which is of paramount importance in addressing global water scarcity concerns.