Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC ...Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.展开更多
Slurry pipeline transport is widely used in several industrial processes.Calculating the specific power consumption(SPC)and determining the best working conditions are important for the design and operation of transpo...Slurry pipeline transport is widely used in several industrial processes.Calculating the specific power consumption(SPC)and determining the best working conditions are important for the design and operation of transportation systems.Based on the Shanghai Jiao Tong University high-concentration multi-sized slurry pressure drop(SJTU-HMSPD)pipeline-resistance-calculation model,the SJTU-SPC model for calculating the power required to transport a unit volume of solid materials over a unit pipeline length is established for a slurry transport system.The said system demonstrates a uniformity coefficient in the 1.26–7.98 range,median particle size of 0.075–4 mm,particle volume concentration of 10–60%,and pipeline diameter of 0.203–0.8 m.The results obtained were successfully verified against existing experimental data.The influence of parameters,such as particle-gradation uniformity coefficient,median particle size,pipe diameter,and particle volume concentration,on the SPC were analysed.The results revealed that the greater is the uniformity coefficient,the smaller is the minimum specific energy consumption and the larger the optimal transport concentration for a constant,median particle size slurry.As observed,the optimal transport concentration for broad-graded sand equalled approximately 48%.These results supplement the conclusions of existing research,indicating that the optimal transport concentration is approximately 30%and provides theoretical support for high concentration transportation of broad graded slurry.展开更多
This study investigates the application of an enhanced Back-Propagation(BP)neural network model for analyzing and predicting beef microwave drying processes.Based on Fick’s second law of diffusion,effective moisture ...This study investigates the application of an enhanced Back-Propagation(BP)neural network model for analyzing and predicting beef microwave drying processes.Based on Fick’s second law of diffusion,effective moisture diffusivity was determined under varying microwave power levels(70-420 W)and relative humidity conditions(0%,30%,50%).Experimental results revealed moisture diffusivity values ranging from 2.23×10^(–9) to 2.87×10^(–8 )m^(2)/s.A significant inverse relationship was observed between microwave power and specific energy consumption,with optimal energy efficiency(8.39 MJ/kg water)achieved at 420 W.A multi-layer BP neural network architecture was developed to model drying kinetics and energy consumption patterns,with subsequent optimization using Sparrow Search Algorithm(SSA)for weight and threshold parameter calibration.Comparative analysis demonstrated that the SSA-optimized BP neural network significantly outperformed both conventional BP models and genetic algorithm-optimized variants in predictive accuracy.The enhanced model exhibited robust performance in predicting moisture content evolution and energy consumption dynamics throughout the drying process.These findings provide valuable insights for developing energy-efficient industrial-scale beef drying systems while maintaining product quality.The proposed intelligent computing framework represents a promising approach for precise modeling,prediction,and optimization of microwave drying processes in food processing applications.展开更多
In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting spee...In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting speed,cutting angle,and rotational speed)in order to explore their influences on cutting performance.The results indicate that the thrust,torque,vibration velocity,and roughness all increased continuously with increase of the propulsion speed and cutting depth.At the same time,the specific energy consumption was found to decrease continuously.As the rotational speed was increased,the thrust increased at first and then decreased.In contrast,the torque and roughness continuously decreased,and the specific energy consumption and vibration speed continuously increased.When the cutting angle was increased,the thrust remained unchanged.However,the torque,specific energy consumption,and vibration speed all decreased continuously,and the roughness increased continuously.The temperature of the surface of the cutting tool was found to be relatively uniformly distributed during the rock-breaking process;the highest temperatures generated were in the range of 200-300℃.As the propulsion speed,cutting depth,and cutting angle were increased,the proportion of tensile fractures produced appeared to increase and the proportion of shear fractures decreased.As the rotational speed was increased,the proportion of tensile fractures decreased and the proportion of shear fractures increased.The results could provide useful information on the rock-breaking behavior involved and can be used to offer technical support for engineers using master-slave follow-up disc cutters in the field.展开更多
The water quality and energy consumption of wastewater treatment plants(WWTPs)in Taihu Basin were evaluated on the basis of the operation data from 204 municipal WWTPs in the basin by using various statistical methods...The water quality and energy consumption of wastewater treatment plants(WWTPs)in Taihu Basin were evaluated on the basis of the operation data from 204 municipal WWTPs in the basin by using various statistical methods.The influent ammonia nitrogen(NH3-N)and total nitrogen(TN)of WWTPs in Taihu Basin showed normal distribution,whereas chemical oxygen demand(COD),biochemical oxygen demand(BOD5),suspended solid(SS),and total phosphorus(TP)showed positively skewed distribution.The influent BOD5/COD was 0.4%-0.6%,only 39.2%SS/BOD5 exceeded the standard by 36.3%,the average BOD5/TN was 3.82,and the probability of influent BOD5/TP>20 was 82.8%.The average energy consumption of WWTPs in Taihu Basin in 2017 was 0.458 kWh/m^3.The specific energy consumption of WWTPs with a daily treatment capacity of more than 5×10^4 m^3 in Taihu Basin was stable at 0.33 kWh/m^3.A power function relationship was observed between the reduction in COD and NH3-N and the specific energy consumption of pollutant reduction,and the higher the pollutant reduction is,the lower the specific energy consumption of pollutant reduction presents.In addition,a linear relationship existed between the energy consumption of WWTPs and the specific energy consumption of influent volume and pollutant reduction.Therefore,upgrading and operation with less energy consumption of WWTPs is imperative and the suggestions for Taihu WWTPs based on stringent discharge standard are proposed in detail.展开更多
To improve the rock breaking ability, cavitating waterjet and abrasive waterjet are combined by using a coaxial low-speed waterjet generated around the periphery of a high-speed abrasive waterjet, and a new type of wa...To improve the rock breaking ability, cavitating waterjet and abrasive waterjet are combined by using a coaxial low-speed waterjet generated around the periphery of a high-speed abrasive waterjet, and a new type of waterjet called unsubmerged cavitating abrasive waterjet(UCAWJ) is thus produced. The rock breaking performance of UCAWJ was compared with submerged cavitating abrasive waterjet(SCAWJ)and unsubmerged abrasive waterjet(UAWJ) by impinging sandstone specimens. Moreover, the effects of jet pressure, standoff distance, abrasive flow rate and concentration were studied by evaluating the specific energy consumption, and the area, depth, and mass loss of the eroded specimen. The results show that the artificially generated submerged environment in UCAWJ is able to enhance the rock breaking performance under the same operating parameters. Furthermore, the rock breaking performance of UCAWJ is much better at higher jet pressures and smaller standoff distances when compared with UAWJ. The greatest rock breaking ability of UCAWJ appears at jet pressure of 50 MPa and standoff distance of 32 mm, with the mass loss of sandstone increased by 370.6% and the energy dissipation decreased by 75.8%. In addition, under the experimental conditions the optimal abrasive flow rate and concentration are 76.5 m L/min and 3%, respectively.展开更多
Under the condition of the designated collection ratio and the interfused ratio of mullock, to ensure the least energy consumption, the parameters of collecting head （the feed speed, the axes height of collecting hea...Under the condition of the designated collection ratio and the interfused ratio of mullock, to ensure the least energy consumption, the parameters of collecting head （the feed speed, the axes height of collecting head, and the rotate speed） are chosen as the optimized parameters. According to the force on the cutting pick, the collecting size of the cobalt crust and bedrock and the optimized energy consumption of the collecting head, the optimized design model of collecting head is built. Taking two hundred groups seabed microtopography for grand in the range of depth displacement from 4.5 to 5.5 era, then making use of the improved simulated annealing genetic algorithm （SAGA）, the corresponding optimized result can be obtained. At the same time, in order to speed up the controlling of collecting head, the optimization results are analyzed using the regression analysis method, and the conclusion of the second parameter of the seabed microtopography is drawn.展开更多
Agriculture is the largest consumer of freshwater.Desalinated seawater is an important alternative water source for sustainable irrigation.However,some issues of the current desalination technology hinder its use for ...Agriculture is the largest consumer of freshwater.Desalinated seawater is an important alternative water source for sustainable irrigation.However,some issues of the current desalination technology hinder its use for agriculture irrigation,including low boron removal and high energy consumption.This study systematically explored the feasibility of employing fertilizer drawn forward osmosis(FDFO)as an alternative to 2nd pass reverse osmosis(RO)by considering the boron removal performance and specific energy consumption(SEC).Different operating conditions were investigated,such as the boron and NaCl concentrations in feed solution(FS),draw solution(DS)concentration,pH,the volume ratio of FS to DS,membrane orientation,flow rate,and operating temperature.The results indicated that a low boron concentration in FS and high DS pH(pH=11.0)decreased the boron solute flux,and led to low final boron concentration in the DS.The other operating conditions had negligible influence on the final DS boron concentration.Also,a lower flow rate and higher specific water flux with certain permeate water volumes were conducive to reducing the SEC of the FDFO process.Overall,our study paves a new way of using FDFO in irrigation,which avoids the phytotoxicity and human health risk of boron.The results show the potential of FDFO as an alternative to 2nd pass RO for irrigation water production.展开更多
Many industrial products made from fossil fuels cause the problems of global warming,depletion of fossil fuel resources and decrease of the land by landfill.In this report,the amounts of CO2 emissions as the environme...Many industrial products made from fossil fuels cause the problems of global warming,depletion of fossil fuel resources and decrease of the land by landfill.In this report,the amounts of CO2 emissions as the environmental load and the specific energy consumptions as the depletion of fossil fuel resources of biodegradable plastics and conventional plastic as food trays are compared using life cycle assessment methodology.The amount of CO2 emission of PHB(poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) tray was the smallest among those of trays of other plastics.The specific energy consumption of SPCL(starch/polycaprolactone) was the smallest among those of trays of other plastics.It clearly reveals that the utilization of the biodegradable plastics is an effective way of alternatives of the conventional plastics.展开更多
To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion,the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied,and the mechanisms of ultras...To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion,the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied,and the mechanisms of ultrasound and medium were introduced.Experimental results indicate that ultrasound cavitation induces the rise of sludge temperature,which improves ultrasound disintegra-tion on sludge.U1trasound pretreatment can advance observ-ably the quantity of chemical oxygen demand in sludge supernatant fluid(SCOD),which increases with ultrasound intensity and sonication time.The degree of ultrasound disintegration increases with the specific energy input.When the specific energy input is l0000 kJ/kg of total dry solids,the degree of ultrasonic sludge disintegration reaches 40%.展开更多
A key challenge in food drying is achieving an optimal balance between processing efficiency,energy consumption,and maintaining high quality in the final product.This study investigates three drying methods for mango ...A key challenge in food drying is achieving an optimal balance between processing efficiency,energy consumption,and maintaining high quality in the final product.This study investigates three drying methods for mango slices:conventional hot air drying(HA),far-infrared combined hot air drying(FIRHA),and step-down temperature FIRHA.The effects of various operating parameters were analyzed,including drying medium temperature and the influence of far-infrared assistance,on the drying kinetics and quality attributes of the mango slices.The quality attributes assessed include color,shrinkage percentage,texture profile,water activity,microstructure,and energy consumption.The results indicate that the drying rates for FIRHA were significantly higher than those for HA.Mango slices dried using FIRHA and step-down temperature FIRHA exhibited greater lightness and greenness,along with increased crispness,while demonstrating lower yellowness compared to those dried by HA.The far-infrared assistance resulted in larger pore sizes and a higher void area fraction in the mango slices,but it also led to reduced hardness and shrinkage percentage compared to those dried using HA.In terms of specific energy consumption,the electric heater consumed significantly more energy than the far-infrared radiator and blower.Additionally,the total specific energy consumption of step-down temperature FIRHA was lower than that of both HA and FIRHA under all drying conditions.Based on these findings,this study recommends using step-down temperature FIRHA at 90℃ for 1 h for the effective drying of mango slices,offering an optimal solution to the core challenges in the field.Ultimately,this work provides a valuable framework and empirical evidence for the adoption of hybrid drying technologies,contributing significantly to the fields of food engineering and sustainable agricultural processing.展开更多
基金Item Sponsored by Fundamental Research Funds for the Central Universities of China(N090602007)National Key Technology Research and Development Program in 11th Five-Year Plan Project of China(2006BAE03A09)
文摘Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.
基金This research was supported by the National Natural Science Foundation of China(Grant No.51779143)the Cultivation of Scientific Research Ability of Young Talents of Shanghai jiao Tong University(Grant No.19×100040072).
文摘Slurry pipeline transport is widely used in several industrial processes.Calculating the specific power consumption(SPC)and determining the best working conditions are important for the design and operation of transportation systems.Based on the Shanghai Jiao Tong University high-concentration multi-sized slurry pressure drop(SJTU-HMSPD)pipeline-resistance-calculation model,the SJTU-SPC model for calculating the power required to transport a unit volume of solid materials over a unit pipeline length is established for a slurry transport system.The said system demonstrates a uniformity coefficient in the 1.26–7.98 range,median particle size of 0.075–4 mm,particle volume concentration of 10–60%,and pipeline diameter of 0.203–0.8 m.The results obtained were successfully verified against existing experimental data.The influence of parameters,such as particle-gradation uniformity coefficient,median particle size,pipe diameter,and particle volume concentration,on the SPC were analysed.The results revealed that the greater is the uniformity coefficient,the smaller is the minimum specific energy consumption and the larger the optimal transport concentration for a constant,median particle size slurry.As observed,the optimal transport concentration for broad-graded sand equalled approximately 48%.These results supplement the conclusions of existing research,indicating that the optimal transport concentration is approximately 30%and provides theoretical support for high concentration transportation of broad graded slurry.
基金supported by the 2024 Tertiary Education Scientific Research Project of the Guangzhou Municipal Education Bureau(Grant No.2024312026),a grant from the Sugar Creek Packing Company,and the Dale A.Seiberling Endowment to the Food Engineering Research Laboratory at The Ohio State University。
文摘This study investigates the application of an enhanced Back-Propagation(BP)neural network model for analyzing and predicting beef microwave drying processes.Based on Fick’s second law of diffusion,effective moisture diffusivity was determined under varying microwave power levels(70-420 W)and relative humidity conditions(0%,30%,50%).Experimental results revealed moisture diffusivity values ranging from 2.23×10^(–9) to 2.87×10^(–8 )m^(2)/s.A significant inverse relationship was observed between microwave power and specific energy consumption,with optimal energy efficiency(8.39 MJ/kg water)achieved at 420 W.A multi-layer BP neural network architecture was developed to model drying kinetics and energy consumption patterns,with subsequent optimization using Sparrow Search Algorithm(SSA)for weight and threshold parameter calibration.Comparative analysis demonstrated that the SSA-optimized BP neural network significantly outperformed both conventional BP models and genetic algorithm-optimized variants in predictive accuracy.The enhanced model exhibited robust performance in predicting moisture content evolution and energy consumption dynamics throughout the drying process.These findings provide valuable insights for developing energy-efficient industrial-scale beef drying systems while maintaining product quality.The proposed intelligent computing framework represents a promising approach for precise modeling,prediction,and optimization of microwave drying processes in food processing applications.
基金study was supported by the National Key Research and Development Program of China(Grant No.2023YFC2907202)the National Natural Science Foundation of China(Grant No.52404116)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240129).
文摘In this paper,a self-developed master-slave follow-up disc cutter is used to conduct rock-breaking tests on hard sandstone samples.Different working parameters were employed in the tests(e.g.cutting depth,cutting speed,cutting angle,and rotational speed)in order to explore their influences on cutting performance.The results indicate that the thrust,torque,vibration velocity,and roughness all increased continuously with increase of the propulsion speed and cutting depth.At the same time,the specific energy consumption was found to decrease continuously.As the rotational speed was increased,the thrust increased at first and then decreased.In contrast,the torque and roughness continuously decreased,and the specific energy consumption and vibration speed continuously increased.When the cutting angle was increased,the thrust remained unchanged.However,the torque,specific energy consumption,and vibration speed all decreased continuously,and the roughness increased continuously.The temperature of the surface of the cutting tool was found to be relatively uniformly distributed during the rock-breaking process;the highest temperatures generated were in the range of 200-300℃.As the propulsion speed,cutting depth,and cutting angle were increased,the proportion of tensile fractures produced appeared to increase and the proportion of shear fractures decreased.As the rotational speed was increased,the proportion of tensile fractures decreased and the proportion of shear fractures increased.The results could provide useful information on the rock-breaking behavior involved and can be used to offer technical support for engineers using master-slave follow-up disc cutters in the field.
文摘The water quality and energy consumption of wastewater treatment plants(WWTPs)in Taihu Basin were evaluated on the basis of the operation data from 204 municipal WWTPs in the basin by using various statistical methods.The influent ammonia nitrogen(NH3-N)and total nitrogen(TN)of WWTPs in Taihu Basin showed normal distribution,whereas chemical oxygen demand(COD),biochemical oxygen demand(BOD5),suspended solid(SS),and total phosphorus(TP)showed positively skewed distribution.The influent BOD5/COD was 0.4%-0.6%,only 39.2%SS/BOD5 exceeded the standard by 36.3%,the average BOD5/TN was 3.82,and the probability of influent BOD5/TP>20 was 82.8%.The average energy consumption of WWTPs in Taihu Basin in 2017 was 0.458 kWh/m^3.The specific energy consumption of WWTPs with a daily treatment capacity of more than 5×10^4 m^3 in Taihu Basin was stable at 0.33 kWh/m^3.A power function relationship was observed between the reduction in COD and NH3-N and the specific energy consumption of pollutant reduction,and the higher the pollutant reduction is,the lower the specific energy consumption of pollutant reduction presents.In addition,a linear relationship existed between the energy consumption of WWTPs and the specific energy consumption of influent volume and pollutant reduction.Therefore,upgrading and operation with less energy consumption of WWTPs is imperative and the suggestions for Taihu WWTPs based on stringent discharge standard are proposed in detail.
基金financially supported by the National Natural Science Foundation of China (Nos. 52175245 and 52274093)the Natural Science Foundation of Hubei Province (No. 2021CFB462)。
文摘To improve the rock breaking ability, cavitating waterjet and abrasive waterjet are combined by using a coaxial low-speed waterjet generated around the periphery of a high-speed abrasive waterjet, and a new type of waterjet called unsubmerged cavitating abrasive waterjet(UCAWJ) is thus produced. The rock breaking performance of UCAWJ was compared with submerged cavitating abrasive waterjet(SCAWJ)and unsubmerged abrasive waterjet(UAWJ) by impinging sandstone specimens. Moreover, the effects of jet pressure, standoff distance, abrasive flow rate and concentration were studied by evaluating the specific energy consumption, and the area, depth, and mass loss of the eroded specimen. The results show that the artificially generated submerged environment in UCAWJ is able to enhance the rock breaking performance under the same operating parameters. Furthermore, the rock breaking performance of UCAWJ is much better at higher jet pressures and smaller standoff distances when compared with UAWJ. The greatest rock breaking ability of UCAWJ appears at jet pressure of 50 MPa and standoff distance of 32 mm, with the mass loss of sandstone increased by 370.6% and the energy dissipation decreased by 75.8%. In addition, under the experimental conditions the optimal abrasive flow rate and concentration are 76.5 m L/min and 3%, respectively.
基金Project(50875265) supported by the National Natural Science Foundation of ChinaProject(20080440992) supported by the Postdoctoral Science Foundation of ChinaProject(2009SK3159) supported by the Technology Support Plan of Hunan Province,China
文摘Under the condition of the designated collection ratio and the interfused ratio of mullock, to ensure the least energy consumption, the parameters of collecting head （the feed speed, the axes height of collecting head, and the rotate speed） are chosen as the optimized parameters. According to the force on the cutting pick, the collecting size of the cobalt crust and bedrock and the optimized energy consumption of the collecting head, the optimized design model of collecting head is built. Taking two hundred groups seabed microtopography for grand in the range of depth displacement from 4.5 to 5.5 era, then making use of the improved simulated annealing genetic algorithm （SAGA）, the corresponding optimized result can be obtained. At the same time, in order to speed up the controlling of collecting head, the optimization results are analyzed using the regression analysis method, and the conclusion of the second parameter of the seabed microtopography is drawn.
基金supported by the National Key Research and Development Program of China(No.2018YFC040800202)the National Natural Science Foundation of China(Grant No.21878177)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2019LFG003)the grants from the Tai Shan Scholar Foundation(No.ts201511003)。
文摘Agriculture is the largest consumer of freshwater.Desalinated seawater is an important alternative water source for sustainable irrigation.However,some issues of the current desalination technology hinder its use for agriculture irrigation,including low boron removal and high energy consumption.This study systematically explored the feasibility of employing fertilizer drawn forward osmosis(FDFO)as an alternative to 2nd pass reverse osmosis(RO)by considering the boron removal performance and specific energy consumption(SEC).Different operating conditions were investigated,such as the boron and NaCl concentrations in feed solution(FS),draw solution(DS)concentration,pH,the volume ratio of FS to DS,membrane orientation,flow rate,and operating temperature.The results indicated that a low boron concentration in FS and high DS pH(pH=11.0)decreased the boron solute flux,and led to low final boron concentration in the DS.The other operating conditions had negligible influence on the final DS boron concentration.Also,a lower flow rate and higher specific water flux with certain permeate water volumes were conducive to reducing the SEC of the FDFO process.Overall,our study paves a new way of using FDFO in irrigation,which avoids the phytotoxicity and human health risk of boron.The results show the potential of FDFO as an alternative to 2nd pass RO for irrigation water production.
基金sponsored by New Energy and Industrial Development Organization(NEDO)supported by Japanese national government METI and relevant organizations
文摘Many industrial products made from fossil fuels cause the problems of global warming,depletion of fossil fuel resources and decrease of the land by landfill.In this report,the amounts of CO2 emissions as the environmental load and the specific energy consumptions as the depletion of fossil fuel resources of biodegradable plastics and conventional plastic as food trays are compared using life cycle assessment methodology.The amount of CO2 emission of PHB(poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) tray was the smallest among those of trays of other plastics.The specific energy consumption of SPCL(starch/polycaprolactone) was the smallest among those of trays of other plastics.It clearly reveals that the utilization of the biodegradable plastics is an effective way of alternatives of the conventional plastics.
文摘To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion,the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied,and the mechanisms of ultrasound and medium were introduced.Experimental results indicate that ultrasound cavitation induces the rise of sludge temperature,which improves ultrasound disintegra-tion on sludge.U1trasound pretreatment can advance observ-ably the quantity of chemical oxygen demand in sludge supernatant fluid(SCOD),which increases with ultrasound intensity and sonication time.The degree of ultrasound disintegration increases with the specific energy input.When the specific energy input is l0000 kJ/kg of total dry solids,the degree of ultrasonic sludge disintegration reaches 40%.
基金Faculty of Engineering and the Faculty of Science and Technology at Rajamangala University of Technology Phra Nakhon for their support in providing research tools and facilities.
文摘A key challenge in food drying is achieving an optimal balance between processing efficiency,energy consumption,and maintaining high quality in the final product.This study investigates three drying methods for mango slices:conventional hot air drying(HA),far-infrared combined hot air drying(FIRHA),and step-down temperature FIRHA.The effects of various operating parameters were analyzed,including drying medium temperature and the influence of far-infrared assistance,on the drying kinetics and quality attributes of the mango slices.The quality attributes assessed include color,shrinkage percentage,texture profile,water activity,microstructure,and energy consumption.The results indicate that the drying rates for FIRHA were significantly higher than those for HA.Mango slices dried using FIRHA and step-down temperature FIRHA exhibited greater lightness and greenness,along with increased crispness,while demonstrating lower yellowness compared to those dried by HA.The far-infrared assistance resulted in larger pore sizes and a higher void area fraction in the mango slices,but it also led to reduced hardness and shrinkage percentage compared to those dried using HA.In terms of specific energy consumption,the electric heater consumed significantly more energy than the far-infrared radiator and blower.Additionally,the total specific energy consumption of step-down temperature FIRHA was lower than that of both HA and FIRHA under all drying conditions.Based on these findings,this study recommends using step-down temperature FIRHA at 90℃ for 1 h for the effective drying of mango slices,offering an optimal solution to the core challenges in the field.Ultimately,this work provides a valuable framework and empirical evidence for the adoption of hybrid drying technologies,contributing significantly to the fields of food engineering and sustainable agricultural processing.
