(1)The basic characteristics of drying materials and drying media must be mastered in the design of drying equipment. Thermal physical properties of materials(It includes specific heat capacity, thermal conductivity and permissible heating temperature.)Aerodynamics of medium(It includes specific surface area, critical wind speed and air resistance of material layer.). In the design of drying auxiliaries, we should also master the physical characteristics of materials.(Including particle size, friction coefficient, etc.)At present, there are few experimental studies in this field in China, and the accuracy is not high, which limits the improvement of drying equipment quality.

(2)The main requirement of developing new products drying equipment is to ensure the necessary quality indicators.(Such as moisture content, material structure, mechanical properties, etc.)To ensure the best unit energy consumption index. Therefore, it is of great economic significance to use modern new technology to manufacture low energy consumption and high productivity drying equipment.

(3)To strengthen the research of design theory can not meet the requirements and needs to be repeated many times. Therefore, a great deal of heat and mass balance can be made in the design of the drying step corresponding to the design of various drying processes. The calculation is complicated and sometimes all the tables and tables of the initial results, methods and calculation lines can be transported. Human computer adopts computer-aided design to establish expert system, so as to reduce design time and improve design efficiency.

   Development trend of drying equipment

  Due to the different characteristics of materials, drying requirements are different, and there are many kinds of drying equipment. In recent years, drying equipment has generally developed in the following directions.

      ①In order to reduce investment and operation cost, it will develop to super large scale, such as spray drying tower.

      ②A new type of laboratory spray drying equipment was developed, including fluidized bed boiling granulating dryer, etc.

      ③Improve the original drying equipment and strengthen the drying process. By improving the flow of materials in the equipment, add accessories to strengthen and improve the drying process. Improve the operation of dryer and expand the scope of use of dryer.

      ④Using combined drying technology, using more than two different drying equipment in series to complement each other's strengths, such as air flow.-Fluidization, spray fluidization, microwave hot air, drum far-infrared ray and so on.

      ⑤Adopt new physical technology, such as high frequency drying, microwave drying, infrared drying, etc.

      ⑥Developing new energy saving drying technology.  Such as horizontal fast roller dryer, less air chamber type fast dryer, etc.