Investigation on Factors Affecting Batch Drying

In industries including medicines, agriculture, food, fertilizers, and chemicals, drying is among the most crucial processes. It is always desirable to dry the product in less time and area. The drying operation reduces the weight of the product and decreases the transportation cost. Time required for drying, rate of drying, humidity present in fresh air, air velocity, thickness of material are the most important factors for drying operation. In batch drying, pasty materials including wet filter cakes, lumpy solids, and pastes that may be distributed across trays are commonly dried using tray dryers. Hot air is continuously blown on the surface of the trays. Hot air absorbs moisture present in the solids and exhaust air becomes humid. Different types of batch dryer equipment’s are used in industries based up on their role, efficiency, drying rate etc. In the current studies, the impact of air velocity, cake thickness, and air temperature on dryer performance parameters is investigated. Different drying conditions are shown and explained using drying curves. The time required for drying is calculated theoretically and compared with practical time. In drying of foods & vegetables observe that the taste, texture, flavor and color changes, in some cases hardening case occur. It was noted that drying rate decreases with time but improved with air velocity and temperature.