Development and performance assessment of a hybrid solar cabinet dryer for fish drying

Abstract

The fish products can be stored for longer period in dry condition, but most of the fresh fish in remote areas of our country are spoils due to lack of proper preservation. To overcome this problem, hybrid solar dryer can play an important role to make drying continuous during night and daytime also off sunshine hours. In this project, a hybrid solar cabinet dryer has been designed, constructed, and performance tested for fish drying. The dryer consists of a drying chamber, solar collector, two trays of dimensions (60×60) cm and paraffin wax as PCM. It also consists of photovoltaic cell modules, heating element, electric battery, and other electric equipment such as inlet and outlet fans. The dryer has been operated as both a solar energy dryer during normal sunny days and a hybrid solar dryer during cloudy days. Paraffin wax system inside drying chamber absorbed heat energy in Sunny time. At the same time the battery is charged from the solar system and therefore the water kept in the tank reaches a certain temperature by absorbing heat from nature, which provides heat by circulating the water inside the drying chamber during inclement weather. Electric fans are used at the inlet of the solar collector and outlet of the dryer to maintain adequate air flow inside the drying chamber. During the night and cloudy weather paraffin wax and heater system deliver heat to maintain the set temperature in drying chamber. The grain bed in the dryer is heated by air that comes from a separate solar collector, and at the same time, the drying cabinet collects solar energy directly through the transparent walls and roof. The dryer demonstrated the capacity to dry fish to an appropriate moisture level in a reasonable amount of time, and concurrently, it insured that the fish would be of high quality. The drying rate of hybrid solar dryers is evaluated on fresh fish and compared with solar dryers and sun drying under the same climatic conditions.