Thermodynamic analysis of the apple drying process

2005 ◽  
Vol 219 (1) ◽  
pp. 1-14 ◽  
Author(s):  
E. K. Akpinar ◽  
A Midilli ◽  
Y Bicer
Keyword(s):  
Thermodynamic Analysis ◽  
Single Layer ◽  
Second Law Of Thermodynamics ◽  
Energy Utilization ◽  
Drying Process ◽  
Cent Relative Humidity ◽  
Apple Slices ◽  
Drying Conditions ◽  
Drying Chamber ◽  
Exergy Losses

This paper is concerned with thermodynamic analysis of the process of single-layer drying of apple slices by means of a cyclone-type dryer. Using the first law of thermodynamics, energy analysis was performed to estimate the ratios of energy utilization throughout the drying process. Exergy analysis was carried out to determine exergy losses during the drying process by applying the second law of thermodynamics. It was concluded that the exergy losses increased with increasing energy utilization in both trays and the drying chamber. Values of the energy utilization ratio (EUR) of the drying chamber varied in the range 0−41.64 per cent depending on the drying conditions. The most exergy losses took place on the first tray (EUR = 0−21.06 per cent) during the drying of apple slices. It is emphasized that apple slices are sufficiently dried in the range 60−80°C with 20−10 per cent relative humidity and a drying air velocity of 1.5 m/s over a 3.33−5.33 h period in spite of exergy losses of 0−1.243 kj/s (EUR = 0−34.72 per cent).

Single Layer Drying Behavior of Apple Slices in a Microwave Dryer

2011 ◽  
Vol 312-315 ◽  
pp. 842-847 ◽  
Author(s):  
Soner Çelen ◽  
Kamil Kahveci ◽  
Ugur Akyol
Keyword(s):  
Microwave Power ◽  
Colour Change ◽  
Single Layer ◽  
Drying Time ◽  
Apple Slices ◽  
Drying Behavior ◽  
Drying Behaviour ◽  
Drying Conditions ◽  
Mean Square Errors ◽  
Microwave Dryer

In this study, the drying behaviour of single layer apple slices of 5mm thickness in a microwave dryer was investigated experimentally for four different microwave power levels (90 W, 180 W, 360 W and 600 W) and suitability of drying models available in the literature in simulating the drying behaviour of apple slices was determined by statistical analysis. The performance of these models was determined by comparing the coefficients of determination (R), reduced chi-squares (χ2) and root mean square errors (RMSE) of the models. The results show that drying time and energy consumption decreases considerably with increasing microwave power. The results also show that, among of the models proposed, the Verma et al. model gives the best fit with experimental data for all drying conditions considered. In order to determine the colour change of apple, a colour meter was also used in this study and found that L* and a* values were not significantly different from the values of the fresh apples.

scholarly journals The Effect of Drying Parameters on the Quality of Pork and Poultry-Pork Kabanosy Produced according to the Traditional Specialties Guaranteed Recipe

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Marta Chmiel ◽  
Lech Adamczak ◽  
Katarzyna Wrońska ◽  
Dorota Pietrzak ◽  
Tomasz Florowski
Keyword(s):  
Relative Humidity ◽  
Salt Content ◽  
Raw Material ◽  
Chemical Components ◽  
Drying Process ◽  
Final Yield ◽  
Drying Conditions ◽  
Drying Chamber ◽  
Selection Of

The aim of this study was to determine the effect of differentiated air relative humidity during the drying process on selected quality features of TSG (traditional specialties guaranteed) pork and poultry-pork kabanosy. After heat treatment and 24-hour cooling at 4–6°C, the products were placed in three chambers at 15°C with differentiated air relative humidity: 60, 70, and 80%, respectively. The drying process was carried out until all variants of kabanosy achieved the required final yield of the product (<68%). Color components, water activity and shear force, water, protein, fat, and salt content, and the TBARS indicator values were determined. The drying process might be shortened (~50%) by a reduction of humidity in the drying chamber from 80 to 60%. The changes in the content of chemical components in pork kabanosy compared to poultry-pork ones demonstrated the different dynamics of the drying of the two types of kabanosy and the need for the selection of optimum drying conditions relative to raw material composition.

scholarly journals Influence of the low temperature drying process on optical alternations of organic apple slices

2018 ◽  
Author(s):  
Christian Andre Kopp ◽  
M. Bantle ◽  
I.C. Claussen ◽  
I. Tolstorebrov
Keyword(s):  
Product Quality ◽  
Color Space ◽  
Optical Parameter ◽  
Convective Drying ◽  
Sensor Technology ◽  
Drying Process ◽  
Camera System ◽  
Apple Slices ◽  
Drying Conditions ◽  
Conventional Systems

Drying conditions for convective driers are often based on empirical approaches in which the final product quality is evaluated post processing. Modern sensor technology and data processing enable second-by-second quality analyses but conventional systems do not utilize this possibility. An industrial convective drying chamber was modified with a camera system to investigate the product during the drying process. The obtained data was analyzed on color alternation (CIE-L*a*b* color space and Browning Index), shrinkage and deformation. Both, shrinkage and deformation show minor dependence on drying conditons. The investigation shows the time depending optical parameter at different drying conditions. This might offer new "smart" drying programs with focus on improved product quality. Keywords: color alternation; shrinkage; deformation; convective drying; smart drying

scholarly journals ANALISIS EKSERGI PENGERINGAN IRISAN TEMULAWAK

2016 ◽  
Vol 36 (01) ◽  
pp. 96
Author(s):  
Lamhot Parulian Manalu ◽  
Armansyah Halomoan Tambunan
Keyword(s):  
Exergy Analysis ◽  
Second Law Of Thermodynamics ◽  
Exergy Efficiency ◽  
Energy Utilization ◽  
Second Law ◽  
Process Conditions ◽  
Drying Process ◽  
Conservation Of Energy ◽  
Thin Layer Drying ◽  
Curcuma Xanthorrhiza

Java turmeric (Curcuma xanthorrhiza Roxb.) is a medicinal plant used as raw material for making herbal medicine, its rhizome cut into slices and dried so called simplicia. Curcuma has a harvest moisture content is high enough to need a great energy for drying. Generally, the theory used to analyze the energy efficiency is the first law of thermodynamics that describes the principle of conservation of energy. However, this theory has limitations in measuring the loss of energy quality. To determine whether the energy used in the drying process has been used optimally in terms of quality, the second law of thermodynamics -known as exergy analysis- is used. The purpose of this study is to determine the efficiency of the thin layer drying of curcuma slices with exergy analysis. The results show that the process conditions affect the energy utilization ratio and exergy efficiency of drying. Exergy analysis method based on the second law of thermodynamics has been used to determine the amount of exergy destroyed so that the efficiency of the drying process can be determined more accurately. Exergy efficiency varies between 96.5%-100% for temperatures of 50 °C to 70 °C at 40% RH and 82.3% - 100% for 20% to 40% RH at 50 °C.Keywords: Drying, energy, exergy efficiency, curcuma slices ABSTRAKTemulawak (Curcuma xanthorrhiza Roxb.) merupakan tanaman obat yang simplisianya digunakan sebagai bahan baku pembuatan jamu atau obat tradisional. Pengeringan merupakan proses utama dalam memproduksi simplisia. Untuk menganalisis efisiensi energi suatu proses pengeringan umumnya digunakan hukum termodinamika pertama yang menjelaskan tentang prinsip kekekalan energi. Akan tetapi teori ini mempunyai keterbatasan dalam mengukur penurunan kualitas energi. Untuk mengetahui apakah energi yang digunakan pada proses pengeringan sudah digunakan secara optimal dari sisi kualitas, digunakan hukum termodinamika kedua atau yang dikenal dengan analisis eksergi. Tujuan penelitian ini adalah menentukan efisiensi proses pengeringan lapisan tipis irisan temulawak dengan metode analisis energi dan eksergi. Dalam studi ini, metode analisis energi dan eksergi berdasarkan hukum termodinamika pertama dan kedua telah digunakan untuk menghitung rasio penggunaan energi dan besaran eksergi yang musnah (exergy loss). sehingga efisiensi proses pengeringan irisan temulawak dapat ditentukan secara akurat. Hasil penelitian menunjukkan bahwa kondisi proses pengeringan mempengaruhi rasio penggunaan energi dan efisiensi eksergi pengeringan. Semakin tinggi suhu dan RH pengeringan maka rasio penggunaan energi semakin rendah dan efisiensi eksergi semakin tinggi. Efisiensi eksergi pengeringan temulawak bervariasi antara 96,5%-100% untuk selang suhu 50 oC hingga 70 oC pada RH 40% serta 82,3% - 100% untuk selang RH 20% hingga 40% pada suhu 50 oC. Kata kunci: Pengeringan, energi, efisiensi eksergi, temulawak

Exergy Distribution Characters Analysis of a 130t/h Biomass-Fired Boiler

2015 ◽  
Vol 713-715 ◽  
pp. 1356-1359
Author(s):  
Fang Yang ◽  
Chang Qing Dong ◽  
Zhi Zhong Kang ◽  
Zong Ming Zheng ◽  
Xiao Ying Hu
Keyword(s):  
Heat Balance ◽  
Exergy Analysis ◽  
Second Law Of Thermodynamics ◽  
Energy Utilization ◽  
Analysis Model ◽  
The Real ◽  
First Law Of Thermodynamics ◽  
The Heat Balance ◽  
Exergy Losses

Currently, most of the boilers in power plant are designed by the heat balance based on first law of thermodynamics only, and it analyses the condition of using energy from the perspective of quantity of energy. However, The real energy utilization should be justified not only from the quantity but also from the quality, because the quality of energy based on second law of thermodynamics can reflect the irreversibility in processes and components. In order to revealing the real energy losses, we must establish exergy analysis model of 130t/h Biomass-Fired Boiler. This article calculates the exergy losses of all kinds of boiler surface and the overall exergy efficiency of boiler, together with exergy distribution characters analysis result of 130t/h Biomass-Fired Boiler. The results obtained open out the greatest exergy loss and the place to generate these losses of boiler, and provide scientific gist for improving utilization of boiler energy.

scholarly journals Energetic and exergetic analysis of a convective drier: A case study of potato drying process

2020 ◽  
Vol 5 (1) ◽  
pp. 563-572
Author(s):  
Iman Golpour ◽  
Mohammad Kaveh ◽  
Reza Amiri Chayjan ◽  
Raquel P. F. Guiné
Keyword(s):  
Energy Consumption ◽  
Research Work ◽  
Specific Energy Consumption ◽  
Exergy Efficiency ◽  
Operating Conditions ◽  
Energy Utilization ◽  
Convective Drying ◽  
Drying Time ◽  
Energy And Exergy ◽  
Exergy Losses

AbstractThis research work focused on the evaluation of energy and exergy in the convective drying of potato slices. Experiments were conducted at four air temperatures (40, 50, 60 and 70°C) and three air velocities (0.5, 1.0 and 1.5 m/s) in a convective dryer, with circulating heated air. Freshly harvested potatoes with initial moisture content (MC) of 79.9% wet basis were used in this research. The influence of temperature and air velocity was investigated in terms of energy and exergy (energy utilization [EU], energy utilization ratio [EUR], exergy losses and exergy efficiency). The calculations for energy and exergy were based on the first and second laws of thermodynamics. Results indicated that EU, EUR and exergy losses decreased along drying time, while exergy efficiency increased. The specific energy consumption (SEC) varied from 1.94 × 105 to 3.14 × 105 kJ/kg. The exergy loss varied in the range of 0.006 to 0.036 kJ/s and the maximum exergy efficiency obtained was 85.85% at 70°C and 0.5 m/s, while minimum exergy efficiency was 57.07% at 40°C and 1.5 m/s. Moreover, the values of exergetic improvement potential (IP) rate changed between 0.0016 and 0.0046 kJ/s and the highest value occurred for drying at 70°C and 1.5 m/s, whereas the lowest value was for 70°C and 0.5 m/s. As a result, this knowledge will allow the optimization of convective dryers, when operating for the drying of this food product or others, as well as choosing the most appropriate operating conditions that cause the reduction of energy consumption, irreversibilities and losses in the industrial convective drying processes.

scholarly journals Cherry Tomato Drying: Sun versus Convective Oven

Horticulturae ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 40
Author(s):  
Vincenzo Alfeo ◽  
Diego Planeta ◽  
Salvatore Velotto ◽  
Rosa Palmeri ◽  
Aldo Todaro
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Drying Process ◽  
Drying Time ◽  
Oven Drying ◽  
Sun Drying ◽  
Different Temperatures ◽  
Final Water Content ◽  
Drying Curves ◽  
Drying Conditions

Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content of 15%. However, less drying time, about 10–11 h, was needed when starting with an initial moisture content of 92%. The tomato tissue had high ORAC and polyphenol content values after convective oven drying at 60 °C. The dried tomato samples had a satisfactory taste, color and antioxidant values.

Thermodynamic Analysis of a Multi-Fueled Single Cylinder SI Engine

2011 ◽  
Author(s):  
M. Z. Haq ◽  
M. R. Mohiuddin
Keyword(s):  
Thermodynamic Analysis ◽  
Chemical Properties ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Si Engine ◽  
Gaseous Species ◽  
Single Cylinder ◽  
Engine Cylinder ◽  
Si Engines

The paper presents a thermodynamic analysis of a single cylinder four-stroke spark-ignition (SI) engine fuelled by four fuels namely iso-octane, methane, methanol and hydrogen. In SI engines, due to phenomena like ignition delay and finite flame speed manifested by the fuels, the heat addition process is not instantaneous, and hence ‘Weibe function’ is used to address the realistic heat release scenario of the engine. Empirical correlations are used to predict the heat loss from the engine cylinder. Physical states and chemical properties of gaseous species present inside the cylinder are determined using first and second law of thermodynamics, chemical kinetics, JANAF thermodynamic data-base and NASA polynomials. The model is implemented in FORTRAN 95 using standard numerical routines and some simulation results are validated against data available in literature. The second law of thermodynamics is applied to estimate the change of exergy i.e. the work potential or quality of the in-cylinder mixture undergoing various phases to complete the cycle. Results indicate that, around 4 to 24% of exergy initially possessed by the in-cylinder mixture is reduced during combustion and about 26 to 42% is left unused and exhausted to the atmosphere.

scholarly journals EXPERIMENTAL INVESTIGATION OF CLAY-STRAW BUILDING FINISHING LAYER UNDER DIFFERENT DRYING CONDITIONS

2016 ◽  
Vol 8 (2) ◽  
pp. 65-70
Author(s):  
Tadas Tamošiūnas ◽  
Romas Girkontas ◽  
Andrius Savickas ◽  
Šarūnas Skuodis ◽  
Lumir Mica
Keyword(s):  
Main Idea ◽  
Life Time ◽  
Analysis Program ◽  
Drying Process ◽  
Environmental Friendly ◽  
Bright Yellow ◽  
Before And After ◽  
Yellow Clay ◽  
Drying Conditions ◽  
Clay Tiles

This manuscript represents investigation of six different clay mixtures under variable drying conditions, namely: bright yellow clay (typical for Lithuania), brown clay (Lithuania Sergėnai district), mixture of different clays, white Spanish clay, clay mass which is resistant for thermal coldness (with synthetic cardigan) and Lithuanian coarse clay with granite additives. Drying process was provided imitating natural drying process and fast drying in drying oven at 110 C°. The main idea of this study – imitate clay and clay-straw buildings drying process and to determine which of used clay types had smallest volumetric and linear deformations. Volumetric and linear deformations for clay-straw buildings is one of the most important factors evaluating cracking in this type of buildings. To reach this purpose six tiles of different clay types were used. Before drying stage water content, plasticity, and liquid limits index, respectively was determined for all types of clay. All clay tiles volumetric and linear deformations before and after drying process were measured with specialized view analysis program in order not to damage samples’ form. According to the obtained results a clay type whith the smallest deforamations (volumetric and linear) was found. With the smallest volumetric and linear deformations clay-straw building is not only environmental friendly, sustainable and green, but it does not require a lot of maintenance during building life time.

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