Since ancient times, humans have been accustomed to drying materials with natural heat sources and natural ventilation, which are completely restricted by natural conditions and have low production capacity. With the development of production, they are gradually replaced by artificially controllable heat sources and air dehumidifiers.
Modern air dryers began to use fixed-bed air dryers with intermittent operation. In the middle of the 19th century, the use of tunnel air dryers marked the development of air dryers from intermittent operation to continuous operation. The rotary cylinder air dryer better realizes the agitation of the granular materials, and the drying capacity and strength are improved. Some industries have developed continuous operation air dryers that meet the requirements of the industry, such as drum air dryers in the textile and paper industries.
At the beginning of the 20th century, the production of dairy products began to use spray air dryers, which provided powerful tools for large-scale drying of liquid materials. Since the 1940s, with the development of fluidization technology, high-strength, high-productivity fluidized beds and airflow air dryers have appeared one after another. The freezing sublimation, radiation and dielectric air dryers provide new means to meet special requirements. The development of far-infrared and microwave air dryers began in the 1960s.
