15 research outputs found
Present status of peanuts and progression in its processing and preservation techniques
Peanut or groundnut is one of the major oilseed crops in the world. It is rich in oil and proteins. Developing countries account for about 95% of the world peanut production. Asia alone accounts for 70% of this amount where the major producers India and China together represent over two-third of global output. Traditionally, groundnuts are dried in open sun to its safe moisture level for storage. Natural and artificial (hot air drying) drying methods of groundnuts are being used throughout the world. Artificial peanuts drying devices consume very large amount of energy. In this paper, present status of peanut and a comprehensive review of its drying methods are discussed. Recent developments in preservation and storage of groundnuts are also highlighted
FORCED CONVECTION DRYING OF INDIAN GROUNDNUT: AN EXPERIMENTAL STUDY
In this paper, convective and evaporative heat transfer coefficients of the Indian groundnut were computed under indoor forced convection drying (IFCD) mode. The groundnuts were dried as a single thin layer with the help of a laboratory dryer till the optimum safe moisture storage level of 8 – 10%. The experimental data were used to determine the values of experimental constants C and n in the Nusselt number expression by a simple linear regression analysis and consequently, the convective heat transfer coefficient (CHTC) was determined. The values of CHTC were used to calculate the evaporative heat transfer coefficient (EHTC). The average values of CHTC and EHTC were found to be 2.48 W/m2 oC and 35.08 W/m2 oC, respectively. The experimental error in terms of percent uncertainty was also estimated. The experimental error in terms of percent uncertainty was found to be 42.55%. The error bars for convective and evaporative heat transfer coefficients are also shown for the groundnut drying under IFCD condition
A review on applications of greenhouse drying and its performance
Limited sources and rising cost of fossil fuels has instigated researchers to look towards renewable energy resources. Among renewable energy resources, solar energy is required to become indispensable in the future, as it is inexpensive, abundant, inexhaustible, environmental friendly and non-pollutant. Most of the people living in developing countries are dependent on agriculture. Agricultural products are dried to increase the storage life, minimize the packaging requirement and reduce the transportation weight. Solar drying for drying agricultural products is being practiced since long back throughout the world. Because of its drawbacks, advance technique, i.e. greenhouse drying, is being adopted for drying crops to reduce the drying time and increase the quality of the food products. Some new methods have also been attempted to increase the drying efficiency of greenhouse. In this paper, a comprehensive review of greenhouse drying of various commodities is presented. Different parameters such as thermal analysis, drying characteristics of crops, energy and exergy analysis, and greenhouse drying performance were discussed. In addition, the economical aspects of greenhouse dryers were also highlighted. This review paper will be helpful to the new researchers to know about the various technical aspects of the greenhouse dryer.
Development of empirical expression for thin layer groundnut drying under open sun and forced convection modes
The thin layer drying behaviour of groundnut was investigated under open sun drying (OSD) and indoor forced convection drying (IFCD) modes. The groundnut samples were dried from initial moisture content of 38% (w.b.) to the safe storage moisture content of 8-10% (w.b.). Four mathematical models were compared for describing the groundnut drying process. The performance of thin layer drying models was investigated by comparing the statistical parameters such as coefficient of correlation (R), reduced chi-square (χ2), root mean square error (RMSE), and mean bias error (MBE) between experimental and predicted moisture ratios. Henderson and Pabis model was observed to give the highest value of R and lowest values of χ2, RMSE and MBE for the groundnut drying under both OSD and IFCD modes. The values of statistical parameters under Lewis model were also found to be very close to Henderson and Pabis model. Therefore, Henderson and Pabis and Lewis models were found to be the best for describing the drying behaviour of groundnut under both given conditions.
An Experimental Study on Open Sun Drying of Vermicelli
In this research paper, an attempt has been made to determine the convective heat transfer coefficients of vermicelli for different thicknesses under open sun drying mode. Various experiments were conducted in the months of March and April 2012 for open sun drying of vermicelli in the climatic conditions of Rohtak (28o 40’: 29 05’N 76o 13’: 76o 51’E). Experimental data were used to evaluate the values of constants (C and n) in the Nusselt number expression by using linear regression analysis and consequently convective heat transfer coefficients were determined. The average values of convective heat transfer coefficients were found to be 5.61 W/m2 oC and 4.13 W/m2 oC for vermicelli of diameters 2 mm and 1.25 mm respectively. The experimental errors in terms of percent uncertainty have also been evaluated
Effect of mass on convective heat transfer coefficient during open sun drying of groundnut
The effect of open sun and indoor forced convection on heat transfer coefficients for the drying of papad
In this research paper, a simulation study has been carried out for the determination of convective heat transfer coefficients of papad under open sun drying and indoor forced convection drying modes. Experimental data obtained from open sun and indoor forced convection drying modes for papad were used to determine the values of the constants (C and n) in Nusselt number expression by using linear regression analysis, and consequently convective heat transfer coefficients were evaluated. The average values of convective heat transfer coefficients were found to be 3.54 and 1.56 W/m2 oC under open sun drying and indoor forced convection drying modes respectively. The experimental errors in terms of percent uncertainty were also evaluated
