Thermal performance and kinetic analysis of vermicelli drying inside a greenhouse for sustainable development

Abstract

In this research paper, vermicelli samples of 3 mm, 2 mm, and 1.25 mm diameters have been dried inside an even span greenhouse (1.2 × 0.8 m2 effective floor area) under forced convection mode in the climatic conditions of Rohtak, India (28°54′ N 76°34′E). The vermicelli samples were dried until safe moisture content was achieved. The present setup based on sustainable development due to thermal energy taken from sun, which has always an edge, compared to conventional drying in which high-grade energy (electric) is converted into low-grade energy (heat). The overall average values of thermal efficiency, energy efficiency, and exergy efficiency of greenhouse dryer for drying vermicelli were evaluated as 11.15%, 34.83% and 2.03% respectively. Energy consumption and specific energy consumption of greenhouse dryer for drying vermicelli were found in the range of 0.279 to 0.539 kWh and 0.092 to 0.235 kJ/kg which was observed significantly lower than other drying methods. The drying kinetics of thin layer vermicelli has also been investigated. Lewis model was found to be most suitable to describe the thin layer drying behaviour of vermicelli drying under forced convection sustainable greenhouse drying mode.

Practical applications.

Traditionally, vermicelli is dried in open sun, but its colour and quality gets deteriorated due to exposure to ultraviolet rays, dust, animals, birds, rainfall etc. In industries, vermicelli is dried by electrical/hot air dryers, which consumes lot of energy and makes it costly. Therefore, a practical and advanced method of drying is essential to be developed. Greenhouse drying is an efficient, low cost and energy‐saving advanced technology, compared to the conventional hot air drying and open sun drying. This study proved to be feasible and efficient to work out an optimized drying condition for vermicelli drying under greenhouse, which could give a new path in vermicelli processing industry. The quality of dried vermicelli is good and can be stored for a long time.