DESIGN AND DEVELOPMENT OF SOLAR TUNNEL DRYER WITH CONTROL SYSTEM FOR LARGE SCALE DRYING OF AGRO PRODUCTS

G. SARAVANAPRIYA¹*, R. MAHENDIRAN^2
1ICAR - Centre on Bioconversion Technology, Sri Parasakthi College for Women, Courtallam, 627 802, Tamil Nadu, India
²Department of Bioenergy, Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, 641 003, Tamil Nadu, India
* Corresponding Author : saravanapriya.g@gmail.com

Received : 17-08-2017     Accepted : 23-08-2017     Published : 30-08-2017
Volume : 9     Issue : 40       Pages : 4626 - 4631
Int J Agr Sci 9.40 (2017):4626-4631

Keywords : Coconuts, Solar Tunnel Dryer, Moisture, Drying Rate, Automatic Control System
Academic Editor : Dr Gitam Singh
Conflict of Interest : None declared
Acknowledgements/Funding : The authors acknowledge the monetary support from Department of Science and Technology, Government of India. The physical and infrastructural assistance from Department of Bioenergy, Agricultural Engineering College and Research Institute, TNAU, Coimbatore is greatly acknowledged
Author Contribution : Corresponding Author [G Saravanapriya1*] and Author [R Mahendiran2] designed, developed, and installed the system and carried out the experimental trials and data analysis. Draft the manuscript and revised critically and approved the research paper for pu

Drying of agro products is one of the most important post harvest operations in agricultural processing. This paper presents the design. Development and experimental investigations of solar tunnel dryer with control system for drying agro product (coconuts). The experiments were conducted in a hemispherical shaped solar tunnel dryer for drying coconuts and compared with open sun drying. The weather parameters such as ambient temperature and ambient RH, wind velocity, wind direction, solar radiation and rainfall were monitored along with dryer temperature and relative humidity. The dryer temperature and relative humidity was monitored and controlled with control system using exhaust fans at chimneys. The coconuts were loaded in a tray and trolley system inside the dryer and drying experiments were performed between 9.00 a.m. to 5.00 p.m. It was found that the time required to dry coconuts from initial moisture content of 110.5 per cent (d.b) to a final moisture content of around 7.36 per cent (d.b) in solar tunnel drying mode was 49.5 hours, whereas 80 hours for open sun drying mode. The drying characteristics such as moisture reduction, drying rate and moisture ratio were analyzed.

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