INVESTIGATION OF APPLICABILITY OF A DESICCANT AND HEAT PUMP SYSTEM IN FOOD DRYING

Drying air temperature is of great importance in obtaining high quality dried food. The use of drying air at high temperatures reduces drying time, but it can cause nutritional and structural disorders especially in food products that are sensitive to temperature. Drying air at low temperatures causes an increase on drying time and as a result, molds can develop. As well as molding causes quality and product losses, it can also cause health problems. To prevent these problems, it is necessary to reduce the drying time. Modern low-temperature drying systems have been of interest for many researchers to maintain product quality and save energy. In the scope of this thesis, a hybrid drying system is designed in order to obtain drying air at low temperature and moisture content, using the rotary desiccant wheel and heat pump together. In the system, it is aimed to use two dehumidification processes (rotary desiccant wheel and evaporator of heat pump) at the same time to reduce the drying time and to protect the product quality. A model was formed to analyze the system designed in the study according to different parameters and peanuts were determined as the drying product. At the end of the study, it has been observed that the system proposed in this thesis has a higher performance compared to other desiccant drying systems with different configurations, and the drying time decreases in case of using drying air at low temperature and moisture, and ambient air conditions affected the system performance. From the analyzes, it has determined that the optimum wheel speed of the solid desiccant wheel, which is one of the basic elements of the system, is 10 RPH. In the study, it has been determined that the system discussed in the thesis is suitable for use in food drying applications, especially in obtaining high quality dried food.