The moisture content and temperature variation in contact drying process of paper

In order to reveal the change law of moisture content and temperature in drying technology of cylinder, then guiding the design of drying structure and reducing energy consumption. Based on the principle of conservation of mass, this paper establishes a mathematical model for the evaporation of held water at dry end during the contact drying process of paper; The analytical formula of water content is obtained by combining the fixed conditions; The effects of initial moisture content (initial dryness), air velocity and heat source temperature on moisture content and paper temperature in drying process are simulated. The results show that the size of parameters do not change the overall exponential decay trend of evaporation law, but they change the slope of attenuation in the decline stage of drying process. The initial moisture content is smaller, the absolute value of curve descending slope is greater, but the time needed for drying is longer; The air velocity is larger, the absolute value of curve descending slope is greater, and the time is shorter; The heat source temperature is higher, the drying rate is bigger, the time is shorter, the theoretical analysis is in line with the actual production process. © 2019 Korean Technical Assoc. of the Pulp and Paper Industry. All rights reserved.