STUDYING KINETICS OF POLYCAPRAMIDE DRYING PROCESS

SSTLMK

Abstract

The article analyzes the kinetics of the polycaproamide drying process. Polycaproamide is a popular production material with high performance properties. After extraction, the moisture content of polycaproamide is 13-15%, but for further use in production this parameter should be no more than 0.05%, which determines the importance of ensuring high-quality drying of the material. The features of the polycaproamide drying process are a high level of water absorption - 2-3% moisture by weight in air and 6-8% in water, as well as a sharp slowdown in the drying process at low humidity values, which leads to uneven distribution of moisture. To ensure thorough drying of the material, it is necessary to calculate the kinetics of dehydration of polycaproamide granules. To achieve the goal of the study, analytical and synthetic methods were used to study secondary materials on the kinetics of the polycaproamide drying process, and a systemic-structural approach was used. Drying is a typical heat and mass exchange process, so its kinetics depends on the form of moisture bond with the material. Drying is the last stage of the technological process of polycaproamide production by a continuous method - hydrolytic polymerization of ε-caprolactam in the melt. The process is carried out in a drying column, in which a nitrogen environment is maintained at a temperature of + 120-140 ° C, for 10-14 hours. Experimental curves of the kinetics of drying polycaproamide granules show that the value of the mass conductivity coefficient has a high dependence on the moisture content and temperature of the dried material. The indicator of the final moisture content is inversely proportional to the values of the starting temperature and nitrogen consumption. The size of the polycaproamide granules has the greatest effect on the final moisture content.