Latest drying technologies and machines

摘要

Drying is one of the most important processes during or after wet processing of textile materials. Normally drying is preceded by hydroextraction which is essential for the removal of excess water by squeezing or suction or by centrifugal force. If not hydro extracted, the wet materials would consume lot of energy during drying. In conventional drying machine, heat energy is supplied by steam or superheated steam or hot oil. Heat is transferred on to the material by conduction, convection and radiation principles. One of the oldest drying machine called cylinder drying machine use conduction principle, whereas machines like float dryer, hot flue dryers in which material is allowed to float or to run over roller, and the heat is applied through hot air by convection principle, most of the dryers which are in use for drying woven and knitted fabrics use the conduction or the convection principles of heat transfer. State of art drying technologies such as infra red radiations, ultra violet radiations and radio frequency drying techniques are increasingly used in latest drying machines.