Analysis of intermittent infrared drying using heat recovery with a novel control methodology

Abstract

Drying is one of the most energy consuming process. By using automatic control systems in the industry, a higher quality and energy efficient drying is achieved. There are two main periods in drying process, the constant rate period and the falling rate period. In the falling rate period, it becomes difficult to evaporate water from the product, and this results in high specific energy consumption values and low energy efficiency values. In this study, apple slices were dried in an intermittent infrared dryer with two new developed drying methodologies as a solution to this problem (Model 2 and 3). An Arduino based automatic control system was used for Model 2 and Model 3. Developed models were compared with conventional experiments (Model 1). With Model 2, a constant drying rate was achieved independently of the moisture content. With Model 3, 57% shorter drying time compared to Model 2 and 16% less energy consumption compared to Model 1 was provided. Also using of the Model 3 the energy efficiency increased as 50% and the specific energy consumption decreased as 48% compared to Model 1. This study offers a solution with high efficiency in industrial usage. Practical Applications Conventional dryers have low energy efficiency and high specific energy consumption. With two novel drying methodologies developed within the scope of this study, a reduction of 16% in energy consumption and increase of 50% in energy efficiency were observed as an alternative to conventional drying. In addition, a constant drying rate was achieved independently of the moisture content. These drying methodologies offer an applicable solution for drying process with high energy efficiency in industrial food drying systems. Thus, it is foreseen to decrease the energy consumption and increase the efficiency in the drying industry, which constitutes a large part of the industrial energy consumption. 1 | INTRODUCTION Drying is a set of natural and technical processes which includes heatmass transfer and basically it reduces moisture of the product for the purpose of increasing the quality of the dried product and facilitating its trading. Thus, longer shelf life can be ensured, the storage and transportation costs can be reduced, and at the same time accessing for affordable and healthy perishable foods such as fresh fruits and vegetables throughout the year can be possible (Riadh, 2015). Removing moisture from the product is an energy-intensive and time consuming process and approximately 15-25% of the energy used in the production sector is spent for drying, so economic aspect should also be considered (Mujumdar, 2008). Drying of food using infrared radiation (IR) attracts attention in terms of superior thermal efficiency, high

Assessment of freeze, continuous, and intermittent infrared drying methods for sliced persimmon

“…The principle of infrared drying is that the infrared rays produced directly penetrate the product without heating the environment and generate vibrating movement in the water molecules. The utilization of infrared drying for product processing offers several notable advantages, including expedited drying durations, elevated thermal efficiency, superior product quality, diminished specific energy consumption (SEC), and a heightened heat‐mass transfer ratio (Dolgun et al., 2020). Two different ways to increase the effectiveness of infrared drying have been mentioned.…”