Uniform Heating Device for a Paper Mill Process

Paper mills use elaborated drying process using hot rollers to dry the paper. In the recent past, use of hot air for drying has gained some interest. The main disadvantage of this method is non-uniform air temperature, which will cause lateral shrinkage of the paper. This paper discusses a new drying system. The process incorporates a porous medium to ensure uniform temperature by flattening the velocity distribution. The new system requires less equipment pieces and utilized less space for the drying process. A cloth is used in place of paper to increase the repeatability of the experiment. This experiment utilized a conveyor system to transport the cloth within the heater section. Variables concerning velocity and temperature values of the heated air, and heater intensity were adjusted to produce the different drying conditions. Forced air propane heater was used as the heat source. Design modifications were made so that the heater is more suitable for this process. The results showed significant improvement of the velocity and feasibility of extending this technology to the actual scale.