scholarly journals Sustainable Energy for Drying of Cashew Kernels – Experimental Research

Drying is an important process in food preservation. In cashew processing industries cashew kernels are dried for easy peeling of the thin brownish sticky layer known as testa. For this it is necessary to reduce the average moisture content of 13% to 5%. Drying is achieved by direct and indirect methods like traditional open sun and using conventional energy through dryers. Due to control of the air properties in indirect drying cashew kernels can be dried at faster rate and can retain their quality. Air flow passages also play an important role in drying process. The objective of the study is to investigate experimentally the energy consumption for drying 1 kg of cashew kernel using electrically assisted heating and to evaluate the feasibility of active solar air dryer for drying in cashew processing industries. An electrical heat-assisted dryer (EHD) and an active solar flat plate collector air dryer (ASAD) systems are designed and developed using locally available materials. Both the systems are tested for reduction in moisture content with series of experiments. EHD is tested with three different drying chambers for optimum drying rate. In its final test drying chamber without baffle plates has resulted in reduction in moisture content to required level by 5% in three hours with drying rate of 2.8 kg/h against 6.5% and 6.8% in single tray version and four trays with baffle plate version. The drying efficiency of drying chamber is found to be 30.54%. In ASAD system the experimental results ensure the drying of cashew kernels within stipulated time of 6 hours with drying rate of 1.66 kg/h and energy consumption of 255 kJ against 270 kJ of electrical heater drying. The drying chamber exhibits an efficiency of 50.89%. The study suggests that the design is feasible to small, cottage industries for cashew kernel drying. The energy savings up to 3750 kJ per day for a batch of 15 kg is possible.

2019 ◽  
Vol 801 ◽  
pp. 345-350
Author(s):  
Ratinun Luampon ◽  
Sungwarn Bunchan ◽  
Bundit Krittacom

This research was proposed to applying stainless wire mesh porous material for specific energy consumption improvement of a hot air dryer. In experimental consist two main parts, first part was a comparison of drying with and without hot air recirculation duct. Second part was a comparison of drying with and without stainless wire mesh porous material in drying chamber and hot air recirculation duct. Tilapia was drying product, stainless wire mesh in drying chamber was constant PPI=8 and 6 layers, stainless wire mesh in hot air recirculation duct was constant PPI=8 and varied layer at 6, 8 and 12 layers and hot air recirculation ratio 40%, 60% and 80%. Experimental result was, drying with hot air recirculation duct was higher drying rate than without recirculation duct and drying rate was increased, drying time was decreased and SEC was decreased with increased hot air recirculation ratio. At recirculation ratio 80%, SEC was lowest and decreased to 54.52% compared with without recirculation duct. Therefrom, the stainless wire mesh porous materials were inserted in the drying chamber and recirculation duct at PPI=8, 6 layers and PPI=8, 12 layers, respectively and used recirculation ratio 80%, it was found that SEC was lowest and decreased as about 62.21%.


2020 ◽  
Vol 13 (2) ◽  
pp. 1-13
Author(s):  
Hary Kurniawan ◽  
Kiki Rizqia Septiyana ◽  
Muhammad Adnand ◽  
Imam Adriansyah ◽  
Hasmi Nurkayanti

Abstrak. Gula semut merupakah salah satu penganekaragaman produk gula palma yang berbentuk butiran atau kristal yang bahan bakunya dapat berasal dari dari nira kelapa, nira aren atau nira siwalan. Salah satu tahapan penting dalam pembuatan gula semut yaitu pengeringan. Penelitian ini bertujuan untuk mempelajari karakeristik pengeringan gula semut menggunakan alat pengering tipe rak yang berbentuk silinder. Alat pengering yang digunakan menggunakan gas LPG sebagai sumber panas. Parameter yang diamati meliputi suhu lingkungan dan suhu bahan di rak atas, tengah dan bawah, suhu udara yang masuk ke ruang pengering (inlet) dan suhu yang meninggalkan ruang pengering (cerobong). Perubahan kadar air gula semut juga diukur setiap waktu. Hasil menunjukkan bahwa suhu udara pengering dan suhu bahan baik di rak atas, tengah dan bawah berbeda signifikan. Sementara itu perubahan kadar air di setiap rak juga menunjukkan hal yang sama yaitu ada perbedaan nyata perubahan kadar air pada rak. Konstanta laju pengeringan sebesar 0,0119 - 0.0212 menit-1. Berdasarkan nilai R2 yang 0,5 menunjukkan bahwa kadar air yang diprediksi mampu menggambarkan kondisi yang mendekati perubahan kadar air yang sesungguhnya selama pengeringan.Characteristics of Drying Gula Semut Using Cylinder Abstract. Gula semut is one of the diversified products of palm sugar in the form of granules or powders made from palm sap, coconut sap, or siwalan sap. Drying is one of the important processes in making gula semut. The purpose of this study was to study the characteristics of drying gula semut using a cylinder geometry of the cabinet dryer. The dryer used LPG gas as a heat source. The parameters observed are the ambient temperature and the temperature of the sample in the top, middle and bottom racks, the temperature of inlet, and chimney. Changes in the moisture content of gula semut are also measured every time. The results showed that the ambient temperature of the drying chamber and the temperature of samples both on the top, middle, and bottom shelves differ significantly. There was a real difference in changes in the water content in the rack. The drying rate constants are 0.0119 to 0.0212 minutes-1. Based on the R2 value 0.5, it showed that the predicted moisture content was able to describe conditions that are close to changes in the actual moisture content during drying.


2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Shitu Abubakar ◽  
Samaila Umaru ◽  
Fatai O Anafi ◽  
Aminu S Abubakar

This study is concerned with development and performance evaluation of a mixed-mode solar  yam dryer. It was done to address the problems of uneven drying of product on different trays coordinate position in a typical indirect multiple trays dryer. Solar energy drying system was designed using the meteorological conditions of Zaria, Nigeria to dry yam slices in the mixed-mode natural convection. The dryer was designed to dry (7 kg) of yam slices. The dimensions of the dryer were: collector length, collector area, height of the drying chamber, chimney height, length of the drying chamber, and Width of the drying chamber were 0.65 m, 0.27 m2, 0.9 m, 0.7 m, 0.5 m, and 0.43 m, respectively. The solar yam dryer was exposed to solar radiation from 10:00 am to 06:00 pm and tested without load and with yam chips of 5 mm average thickness. Meteorological conditions were monitored during the dehydration process. The average drying rate, collector efficiency and drying efficiency were 2.55 kg/s, 42.20% and 25.35%, respectively. The results of performance evaluation of the solar dryer showed that the drying rate decreases by 3% and 8% in the second and third trays relative to the first tray. This shows that the drying rates did not vary significantly with the coordinate positions of the trays.


2015 ◽  
Vol 799-800 ◽  
pp. 1455-1458 ◽  
Author(s):  
Krissadang Sookramoon

A paddy solar tunnel dryer was designed, constructed and fabricated with a 2.112 m2flat plate collector with drying chamber volume of 0.113 m3, this design was improved to satisfy the drying desires of small farmers. The collector-dryer system has been equipped with data acquisition system to evaluate the performance, such as a data logger, K-type thermocouples, and air velocity measuring equipment. No load tests on the dryer; with 1000 cfm (DC) driven fans have been conducted. The performance of the dryer during drying of paddy has also been analyzed for the two configurations. The results, shown by plotting the variation of air temperature, moisture content indicated that the dryer performs better with DC driven fans, as they considerably reduce the fluctuations in the drying air temperature with fluctuating solar radiation. The moisture content reduced from 49.96 to 17.64 MC (% w.b.) in 6 hours. The average drying temperature was 67.75 °C. The heated air was approximately 344.47 W, with the incoming heat in the solar tunnel dryer of 1738.34 W. The thermal efficiency of a solar tunnel dryer was on the average of 22.72%.


2012 ◽  
Vol 622-623 ◽  
pp. 1135-1139 ◽  
Author(s):  
A. Ekphon ◽  
T. Ninchuewong ◽  
S. Tirawanichakul ◽  
Y. Tirawanichakul

The main objective of this research was to study drying kinetics of air dried sheet (ADS) rubber using hot air and simulated drying kinetics by empirical model compared to experimental results. The 10-15 fresh rubber sheet with initial moisture content ranging of 23-40% dry-basis was dried by temperature of 40-70°C and air flow rate of 0.7 m/s. The fresh rubber sheet samples were dried until the desired final moisture content reached to 0.15% dry-basis. The experimental results showed that the drying rate of ADS rubber dried with hot air convection was faster than conventional natural air convection and drying rate was related to drying temperature. The experimental data was statistical non-linear regression analyzed by using 10 conventional empirical models. The coefficient of determination (R2) and root mean square error (RMSE) values were used as the criteria for selecting the best equation to describe the experimental data The results showed that the calculated results of Verma et al.’ model had a good relation to the experimental results. For specific energy evaluation, the results showed that at high drying temperature specific energy consumption of ADS rubber was relatively low compared to drying with low temperature. Finally, the determination of physical quality showed that.


2011 ◽  
Vol 308-310 ◽  
pp. 1586-1589
Author(s):  
Xing Zao Ma ◽  
Chang You Li ◽  
Li Li Zhang ◽  
Wen Hao Shen

In this paper, the deep-bed drying rate was analyzed under different bed depths and air temperatures. It was found that the bed depth had a greater impact on the drying efficiency, and if the initial moisture content of maize and the ventilation temperature are higher, the effect would be much more notable. The results will provide a basis for optimal design of the deep-bed drying devices.


2020 ◽  
Vol 187 ◽  
pp. 03004
Author(s):  
Wannarat Chuatrakool ◽  
Siva Achariyaviriya ◽  
Aree Achariyaviriya ◽  
James C. Moran

The objectives of this research are to design and construct a biomass energy dryer assisted with solar energy for farmers in off-grid communities and to evaluate the performance of the dryer. The dryer consists of a boiler, drying chamber and solar panels. A compressed sponge was used as a drying product. The air temperature distribution and product moisture uniformity inside the drying chamber were measured. The apparatus was tested in three energy modes, solar energy mode, biomass energy mode and biomass/solar energy assisted mode. Drying using biomass/solar energy assisted mode gave a better drying performance compared to the other modes due to the uniform moisture content and air temperature. The average temperature difference between the top and bottom tray was less than 3°C. The average moisture content between the top and bottom tray was very close, less than 0.8% db. In addition, this drying mode can reduce product contamination from smoke ash and combustion.


2017 ◽  
Vol 5 (1) ◽  
pp. 330-338
Author(s):  
Amalia Islami ◽  
Murad ◽  
Asih Priyati

Aim of this research was to determine drying rate and moisture content changes on Greenhouse (ERK) Dryer. Result was showed using graphic by analyzing drying rate characteristics of Greenhouse Dryer. Data analysis was performed using mathematical approach that solved using Microsoft Excel. Method used in this research was experimental method. Based on the results, onion drying using ERK showed decreasing rate of weight changes. Sample shrinkage was 25.7% with average moisture content 60.06% for sample weight 0.187 kg. Average humidity (RH) was lower than ambient humidity on the range of 63.4% to 83.0%. Characteristics of onion drying was the decreasing rate of moisture content of 0.17% with equation MR: y = -0,017 + 1,061, R2 is 0,985. Value of Ln MR at first day was y = -0,019x and decreasing rate of moisture content 0,19%. Whereas decreasing rate at second, third and fourth day were 0,008%, 0,11% and 0,002% respectively for 1 hour interval period. Keywords: red onion, Greenhouse effect, drying rate, dryer   ABSTRAK   Tujuan penelitian ini untuk mengetahui laju pengeringan, penurunan kadar air pada alat pengering ERK. Data hasil penelitian ditampilkan dalam bentuk grafik dengan menganalisis karakteristik laju pengeringan alat pengering ERK. Analisis data dilakukan dengan pendekatan matematis untuk menyelesaikan model perhitungan matematik yang diolah dengan program komputer Microsoft Excel. Metode yang digunakan pada penelitian ini adalah eksperimental dengan melakukan penelitian langsung di lapangan. Hasil penelitian menunjukkan bahwa pengeringan bawang merah menggunakan alat ERK memiliki laju pengeringan menurun dengan dilihat dari perubahan berat yang semakin berkurang. Penyusutan bahan terjadi 25,7% dengan kadar air rata-rata 60,06% dan berat bahan 0,187 kg. Kelembaban ruang pengering rata-rata 63,4%, lebih kecil dari  kelembaban  lingkungan sebesar 83,0%. Bawang merah memiliki karakteristik pengeringan dengan penurunan kadar air 0,17% dan MR: y = -0,017 + 1,061 dengan nilai determinasi R2 = 0,985. Ln MR pada hari pertama terlihat y = -0,019x dengan penurunan kadar air sebesar 0,19%. Sedangkan penurunan kadar air pada hari kedua mencapai 0,008%, hari  ketiga 0,11%, dan hari keempat 0,002% pada interval waktu 1 jam. Kata kunci: bawang merah, ERK, laju pengeringan, pengeringan


2020 ◽  
Vol 13 (2) ◽  
pp. 42-58
Author(s):  
Andi Muhammad Irfan ◽  
Arimansyah Arimansyah ◽  
A. Ramli Rasyid ◽  
Nunik Lestari

Abstrak. Penelitian ini bertujuan untuk menguji unjuk kerja pengering tenaga surya tipe efek rumah kaca pada pengeringan cabai dengan perlakuan low temperature long time (LTLT) blanching. Selain itu, pada penelitian ini juga dilakukan kajian mengenai karakteristik pengeringan cabai yang dipengaruhi oleh perlakuan LTLT blanching, terutama pada kadar air, laju pengeringan, kecepatan pengeringan, dan kualitas warna. Pengujian dilakukan dengan cara mengeringkan cabai merah dengan pretreatment LTLT blanching yang dikombinasikan dengan perlakuan merotasikan rak pengering (R) dan tanpa merotasikan rak pengering (TR). Sebagai kontrol adalah cabai yang dikeringkan tanpa blanching dan tanpa merotasikan rak pengering (K). Hasil penelitian menunjukkan bahwa perlakuan LTLT blanching yang dikombinasikan dengan merotasikan rak pengering (R) merupakan perlakuan yang terbaik, dengan kadar air akhir cabai kering sebesar 9,82% dan sesuai dengan standar SNI. Waktu pengeringan yang dibutuhkan adalah selama 5 hari. Warna cabai kering yang dihasilkan adalah yang terbaik dari dua perlakuan lainnya, dengan nilai L*, a*, dan b* untuk setelah proses LTLT blanching (sebelum proses pengeringan) dan setelah pengeringan berakhir (cabai kering) berturut-turut adalah 36,02, 38,22, 13,62, dan 32,44, 33,89, dan 10,19. Energi yang terpakai untuk pengeringan cabai adalah sebesar 596181 kJ. Perlakuan R ini juga menghasilkan efisiensi pengeringan terbaik, yaitu sebesar 34,01%.Performance of Green House Effect Type Solar Dryer in the Chillies Drying with Low Temperature Long Time Blanching TreatmentAbstract. This study aims to examine the performance of the greenhouse effect type solar dryer on drying chillies with low temperature long time (LTLT) blanching treatment. In addition, a study was also conducted on the characteristics of drying chillies and the final product affected by LTLT blanching treatment, especially in terms of moisture content, drying rate, drying speed, and color. Testing was performed by drying red chilli with LTLT blanching treatment, which was combined with the treatment of rotating dryer rack (R) and without rotating dryer rack (TR). As a control, chillies were dried without blanching treatment and without rotating dryer rack (K). The results show that the LTLT blanching treatment combined with rotating the drying rack (R) is the best treatment, with a final moisture content of 9.82% which is in accordance with SNI standards. The drying time needed is 5 days. The dried chilli color produced is the best of the other treatments, with values of L*, a*, and b* for after the LTLT blanching process and after drying ended, respectively 36.02, 38.22, 13.62, and 32.44, 33.89, 10.19. The energy used for drying chillies is 596181 kJ. This R treatment also produces the best drying efficiency, which is 34.01%.


2016 ◽  
Vol 12 (7) ◽  
pp. 661-671 ◽  
Author(s):  
Samy Marey ◽  
Mohamed Shoughy

Abstract The effects of the drying temperature and the residual moisture content on the drying behavior, energy consumption and quality of dried citrus peels (CPs), which are value-added food ingredients, were studied. The CP samples were dried in a laboratory-scale hot-air dryer at air temperatures from 40 to 70 °C under a constant air velocity of 1 m/s until the desired moisture content for safe storage was reached or until the final moisture level was achieved for the specific drying conditions. Cakes prepared from blends containing different proportions (0 %, 10 %, 15 % and 20 %) of dried CPs were also evaluated for chemical composition and sensory attributes. The optimal drying temperatures were 50–60 °C, and the optimal moisture content was 10±0.2 % w.b.; these conditions reduced the drying time and energy consumption and maximized the product quality. In contrast, over-drying CPs with the higher temperatures and to a final moisture level of 5.4±0.2 % sharply increased the loss of vitamin C, carotenoids as antioxidants and essential oils. Incorporation of 15 % dried orange and mandarin peels in cake formulas increased the dietary fiber by 33.5 % and 29.6 %, the crude fat by 2.9 % and 4.6 % and the ash by 30.6 % and 29.0 %, respectively, whereas the protein and total carbohydrate content decreased slightly. Highly acceptable nutritious cakes could be obtained by incorporating 15 % orange or mandarin peel dried to 10 % w.b. moisture content into the formulation.


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