Activation Energy for Desorption of Water Vapor on Silica Gel Combining Drying System and Double-Condenser Compression Refrigeration System to Reduce Specific Energy Consumption and Drying Air Temperature

2021 ◽  
Author(s):  
Engkos Achmad Kosasih ◽  
Ahmad Zikri ◽  
Muhammad Irfan Dzaky
Keyword(s):  
Activation Energy ◽  
Water Vapor ◽  
Energy Consumption ◽  
Silica Gel ◽  
Air Temperature ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Refrigeration System ◽  
Drying System

scholarly journals Energy Analysis of Greenhouse Dryer for Ficus Carica L. Leaves

2021 ◽  
Vol 39 (3) ◽  
pp. 810-816
Author(s):  
Wan Nurlaila Mat Desa ◽  
Ahmad Fudholi ◽  
Henny Sudibyo ◽  
Ghalya Pikra ◽  
Nugrahaning Sani Dewi ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Air Temperature ◽  
Specific Energy ◽  
Energy Analysis ◽  
Specific Energy Consumption ◽  
Ambient Air ◽  
Double Pass ◽  
Moisture Extraction ◽  
Solar Air Collector ◽  
Mass Basis

In this study, a greenhouse solar dryer with double-pass multi-hollow collector for leaf drying was design, constructed, and evaluated. From the result, the double pass solar air collector with multi-hollow tube is capable of increasing air temperature by 5.5℃-10.8℃ compared to ambient air temperature. Thermal efficiency of the dryer was evaluated for passive and active modes, where 47.2% and 50% are recorded respectively. The moisture reduction on mass basis in passive and active dryer recorded was 44% and 74%, respectively. The specific moisture extraction rate (SMER) and specific energy consumption (SEC) of passive dryer was determined to be 0.198 kg per kWh and 5.047 kWh per kg, and active dryer at 0.210 kg per kWh and 4.769 kWh per kg, respectively.

scholarly journals Desain dan Uji Kinerja Alat pengering Hybrid Dengan Efek Cerobong Tipe Tumpukan untuk Pengeringan Biji Kopi Arabika

2020 ◽  
Vol 7 (3) ◽  
pp. 163-170
Author(s):  
Irwansyah Irwansyah ◽  
Leopold Oscar Nelwan ◽  
Dyah Wulandani
Keyword(s):  
Water Vapor ◽  
Energy Consumption ◽  
Moisture Content ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
The Sun ◽  
Drying Method ◽  
Arabica Coffee ◽  
Coffee Beans ◽  
Chimney Effect

Artificial drying method for arabica coffee beans requires a large consumption of electrical energy. Electricity is needed to rotate the blower which functions to circulate hot air to the dryer so that it can evaporate some of the water contained in the coffee beans. Most of the arabica coffee producing areas in Aceh province have not been reached by the electricity network so the use of artificial dryers cannot be used. To overcome this obstacle, the air flow circulation system with chimney effect can be used to drain dry air. The aim of this research is to design a chimney effect hybrid dryer which is heat source from solar and biomass energy, to test the performance of the dryer and compare it with the sun drying method. Parameters observed were temperature, moisture content and specific energy consumption of solar radiation and biomass. Dryer capacity is 5 kg of arabica coffee beans. The results showed that the chimney effect hybrid dryer can be used to dry 5 kg of coffee beans. The drying show that drying temperature on the dryer chamber ranged between 37.3-60.9°C. To reduce the moisture content of coffee beans from 52.5 to 12.8% bb, it was take 16-17 hours, while the sun drying method takes up to 46 hours (6 days). The total specific energy consumption of hybrid dryer was 57.1 MJ/kg of water vapor, while the specific energy consumption of the drying method was 59.4 MJ/kg of water vapor.

Effect of microwave, infrared, and convection hot-air on drying kinetics and quality properties of okra pods

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hany S. EL-Mesery ◽  
Mona A. Elabd
Keyword(s):  
Energy Consumption ◽  
Air Temperature ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Drying Methods ◽  
Air Velocity ◽  
Rehydration Ratio ◽  
Drying Time ◽  
Shrinkage Ratio ◽  
Hot Air

Abstract Okra pods were dried using the following drying regimes; microwave (MWD), infrared (IRD) and convective hot-air drying (CHD). The objective of this investigate was to report the influences of drying methods on okra quality under different drying conditions. Data analysis showed that rehydration ratio and colour change increased with increase in drying air temperature and air velocity while specific energy consumption and shrinkage ratio decreased with increase in drying air temperature under (CHD). The rehydration ratio and colour of dried okra increased with increase in both infrared intensity but it also increased with a decrease in air velocity under (IRD). In the MWD method, drying time, specific energy consumption and shrinkage ratio decreased with increases in microwave power while the rehydration ratio and colour increased. Optimum drying period, specific energy consumption, colour, shrinkage and rehydration ratio were obtained for microwave drying. The model of Midilli et al. is the greatest for describing the drying curves of okra under all the drying processing conditions.

Optimization of Pistachio Nut Drying in a Fluidized Bed Dryer with Microwave Pretreatment Applying Response Surface Methodology

2017 ◽  
Vol 12 (3) ◽  
Author(s):  
Reza Amiri Chayjan ◽  
Mohammad Kaveh ◽  
Nesa Dibagar ◽  
Moein Zarrin Nejad
Keyword(s):  
Response Surface Methodology ◽  
Energy Consumption ◽  
Fluidized Bed ◽  
Air Temperature ◽  
Specific Energy ◽  
Color Change ◽  
Specific Energy Consumption ◽  
Air Velocity ◽  
Fluidized Bed Dryer ◽  
Total Color Change

Abstract Thin-layer drying kinetics of pistachio nuts were examined experimentally as a function of drying conditions in a fluidized bed dryer with microwave pretreatment. Four drying specifications of diffusivity, shrinkage, specific energy consumption and total color change were calculated and the effects of parameters were studied. Numerous experimentations were conducted at three levels of air temperature (40, 55, 70 °C), air velocity (1.2, 2.93, 4.01 m/s), and microwave power (270, 450, 630 W). The variation ranges of diffusivity, shrinkage, energy consumption and color change were recorded from 5.01×10–10 to 5.07×10–9 m2/s, from 26.95 % to 13.13 %, from 1.04 to 9.23 kWh and from 10.44 to 17.17, respectively. According to response surface methodology, optimum condition of drying process occurred at microwave power of 630, air temperature of 70 ˚C, and air velocity of 1.2 m/s. In this optimum point, the values of diffusivity, shrinkage, specific energy consumption and total color change were 4.865×10–9, 14.22 %, 2.164 kWh and 12.312, respectively.

scholarly journals EFEK PENAMBAHAN EVAPORATOR PADA ATMOSPHERE WATER HARVESTER (AWH) TERHADAP PERFORMA SISTEM

2021 ◽  
Vol 21 (2) ◽  
pp. 74-80
Author(s):  
Juli Mrihardjono ◽  
Didik Ariwibowo ◽  
Sutrisno Sutrisno ◽  
Dista Yoel Tadeus
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Pipe Wall ◽  
Specific Energy Consumption ◽  
Cross Flow ◽  
Electrical Energy ◽  
Vapor Compression ◽  
Refrigeration System ◽  
Air Velocity ◽  
Vapor Compression Refrigeration

Atmosphere Water Harvester (AWH) was investigated to get water collected from air in elevated performance. Improvement was performed by introducing a series-arrangement of two evaporators. Air flew through the evaporators in cross-flow. This arrangement would influence performance of the AWH system in title of COP, MHI, and specific energy consumption. The AWH was designed using vapor compression refrigeration system. Parameter measured to the system were refrigerant temperature in suction and discharge line, inlet and outlet pipe wall temperatures at evaporator and condenser, air velocity enter into evaporator, and electrical energy consumption. Instrument used in this research were refrigerant pressure-temperature gauge, K-type digital thermometer, digital fan anemometer, thermo-hygro meter, and kWh meter. Air temperature and RH data were 36,5 oC, 40%, and 19 oC, 42 %  for inlet and outlet air stram at evaporator, subsequently. With air velocity 1.5 m/s, the COP of the system was 3.7. Water collected  from AWH was 1.1 litres/hour with energy consumption of 1.24 kWh. The AWH could be considered as a water harvester with value of specific energy of 1.13 kWh/litre and MHI of 0,2.

scholarly journals Determination of Drying Characteristics, Energy Consumption and Quality Values of Black Mulberry Fruit (Morus nigra L.) Dried Under Different Conditions

2021 ◽  
Vol 9 (2) ◽  
pp. 425-432
Author(s):  
Muhammed Taşova ◽  
Hakan Polatcı ◽  
Adil Koray Yıldız
Keyword(s):  
Activation Energy ◽  
Energy Consumption ◽  
Specific Energy ◽  
Effective Diffusion ◽  
Specific Energy Consumption ◽  
Diffusion Activation Energy ◽  
Drying Temperature ◽  
Color Parameters ◽  
Mulberry Fruit ◽  
Diffusion Activation

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

scholarly journals Determination of drying kinetics, specific energy consumption, shrinkage, and colour properties of pomegranate arils submitted to microwave and convective drying

2021 ◽  
Vol 6 (1) ◽  
pp. 230-242
Author(s):  
Mohammad Kaveh ◽  
Iman Golpour ◽  
João Carlos Gonçalves ◽  
Sara Ghafouri ◽  
Raquel Guiné
Keyword(s):  
Energy Consumption ◽  
Air Temperature ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Drying Kinetics ◽  
Drying Methods ◽  
Colour Properties ◽  
Drying Time ◽  
Effective Moisture ◽  
Pomegranate Arils

Abstract In this study, the drying kinetics, effective moisture diffusivity (D eff), specific energy consumption (SEC), colour, and shrinkage (S b) of pomegranate arils were compared when dried by convective (CV) drying and microwave (MW) drying. The experiments were performed at air temperature of 50, 60, and 70°C and air velocity of 1 m/s for CV drying and 270, 450, and 630 W for MW drying. The results showed that increasing air temperature and MW power increased the D eff. The calculations demonstrated that the maximum D eff for pomegranate arils was obtained for MW drying (630 W). Maximum SEC for pomegranate arils in the CV dryer was 145.12 kWh/kg, whereas in the MW dryer was 35.42 kWh/kg. In MW dryer, the lowest values of colour change and shrinkage were 6.77 and 50.5%, respectively. Comprehensive comparison of the different drying methods (MW and CV) revealed that MW drying had best drying performance for pomegranate arils, considering the drying time, effective moisture diffusion, SEC, colour, and shrinkage.

Effects of Drying Conditions of Fixed Bed Longan Drying on Optimal Bed Thickness

2007 ◽  
Author(s):  
Aree Achariyaviriya ◽  
Paradorn Nuthong
Keyword(s):  
Energy Consumption ◽  
Air Temperature ◽  
Flow Rate ◽  
Specific Energy ◽  
Air Flow ◽  
Specific Energy Consumption ◽  
Air Flow Rate ◽  
Drying Time ◽  
Bed Thickness ◽  
Drying Conditions

In this work, it is presented a study of the effects of drying conditions on the optimal bed thickness of the whole longan. The criteria for evaluation of the drying process are specific energy consumption and drying time which the difference of moisture between top and bottom of drying chamber is less than 10%dry basis. The mathematical model is developed for finding the effects of the drying conditions on the optimal bed thickness. The drying conditions are drying air temperature, specific air flow rate, and fraction of recycled air. Experimental data were compared with the simulated results to verify the model. Furthermore, the sensitivity analysis of the fraction of air recycled, drying air temperature, specific airflow rate, initial moisture content, and bed thickness of longan are study. The results showed that there was good agreement between the simulated drying rate and those experimentally observed. In addition, there was a well agreement with respect to the shapes of the drying air temperature and product temperature profiles. From the simulated results, the optimal bed thickness of 40 cm, the specific energy consumption of 10.56 MJ/kg-water and drying time of 64.2 h were found. The responsive conditions were drying air temperature of 75°C, the fraction of recycled air of 90%, and the specific air flow rate of 73 kg-dry air/h-kg dry longan.

Sign in / Sign up

Export Citation Format

Share Document