Livshits

pp. 36-47

The article aims to give a physical representation of the electro-thermal equipment operation to enhance its application capabilities in recycling the secondary raw material and describes a number of electrothermics technology applications in this area. The article presents a comparative analysis of the results of the high-frequency and microwave heating. As an example of wastes recycling of the forestry and woodworking industry, is shown an efficient use of high-frequency equipment in the technological processes of drying. The article offers the technological tooling developed by authors for forming the fuel briquettes. This technological equipment allows the use of thermo-mechanical method of their drying. The article describes experimental research results of waste processing of oil-petrol-resistant flexible PVC, cooking fuel briquettes, and facing materials from sawdust, which use a modifying additive as a crumb from the polyethylene waste, thereby increasing the durability of fuel briquettes, warmth, and stability of its combustion. Results of done work have shown the prospects for using the RF power to process the wastes of wood, plastic, and oil-petrol-resistant PVC.

The article describes a mathematical simulation of high frequency (HF) electrothermic of thermoplastics to be applied to a technological system in the form of the five-layer plate, including electrodes, insulators, processed material and studies the influence of heat insulation on the thermoplastic heating. The article presents a mathematical model in the form of a system of nonstationary heat transfer considering the internal heat sources with different boundary conditions and the software to implement it. The software offered in the article enables to study the mutual influence of geometrical and electro-physical parameters of technological systems of HF thermoplastic heating. Based on the calculations presented in numerical and graphic form, the following areas of heating polymer are identified: uniform heating, regional zones of thermal influence of insulators. The article provides the research results of influence of different thickness heat insulation on the distribution of temperature field of thermoplastic. It is determined that one can shift the zone of maximum heating polymer modifying the parameters of insulating layers, thus allowing to improve the welding quality of polymeric items. According to research results, the conclusion has been drawn up that it is desirable to develop a technological process of electro-thermal welding of polymers with the possibility for displacement of the zone of maximum heating (melting) polymer due to changing heat insulation thickness. The developed software allows a new approach to study the HF-heating modes and  have solution of practical tasks for improving the quality of welded joints of parts from thermoplastics.