Stages of synthesis of the automatic control system of a fluidized bed dryer

Abstract

Fluidized bed is one of the most effective methods of drying dispersed materials, which provides intensive heat and mass transfer and allows achieving high productivity with minimized energy costs. Due to the intensive contact between the material and the drying agent, the drying process in such installations occurs very quickly. The undeniable advantages of this method are: high drying speed, its uniformity due to the correct distribution of heat and moisture, which prevents overdrying or underdrying. This method is suitable for drying a wide range of materials, including powders, granules, crystals and other finely dispersed materials. In fluidized bed dryers, it is quite easy to control temperature, air velocity and other process parameters, which allows you to achieve optimal results. And because the material is in a suspended state, the risk of mechanical damage is reduced. These advantages make fluidized bed drying an important process in many industries, including food, pharmaceutical, chemical and others. The implementation of automated control systems (ACS) plays a key role in achieving process stability. At the same time, the fluidized bed itself is a dynamic system where the behavior of the material depends on many factors, such as air velocity, particle size, humidity and temperature. This makes process control difficult, as even small changes in one parameter can lead to significant changes in others due to existing cross-links. This work is a generalization in the planning of the ASA synthesis method by the process of drying sunflower seeds in a fluidized bed grain dryer, which is a complex dynamic multidimensional object with a delay. Moreover, the stages of synthesis take into account the design features of the dryer, its operation in various modes, in particular in the stabilization mode, and the situation with the impossibility of measuring the output signals of the object in full. All stages of the synthesis of ACS by the drying process in a fluidized bed dryer are built on the application of the basic principles of the modern theory of automatic control of complex technological processes.