Articles - Leather Technology Magazine Nº79

Assessment of leather finish film drying using infrared radiation and convection

J. M. Calvillo*, S. Jöns, A. Obregón, S. Alonso
CIATEC A.C. Omega 201, Fraccionamiento Industrial Delta,
C.P. 37545.
León, Gto., Mexico.
* Responsible for the project

Assessment of leather finish film drying using infrared radiation and convection

ABSTRACT

In leather finishing, the use of infrared radiation as an alternative to the traditional convection process is faster and more efficient for finish film drying. Infrared radiation is very versatile: it can be used to evaporate the aqueous vehicle only, preventing a significant increase in the leather temperature. Therefore, an innovative infrared dryer was designed and constructed, and parameters such as infrared panel distance to substrate, number and spacing of panels and leather transport speed were analyzed.
From an experimental array, it was found that spacing is not significant, that is to say, it does not affect the efficiency of the drying process. All other factors may be manipulated to improve the dryer performance. A mathematical-statistical model predicting the evaporation percentage for any film width was developed through the response surface model. The equation and nomograms can be used to find operating conditions to optimize finish drying for specific formulations when using roller, atomizer or curtain machines, thus avoiding the equipment’s trial-and-error tuning.
Furthermore, the formation of the finish film through microscopic techniques and physiochemical analysis for both drying systems was assessed, which validated the parameters optimal levels, achieving the prototype maximum performance.
This research may be useful in increasing the efficiency of finish film drying, reducing leather manufacturing costs for the leather tanning industry, since this design was found to reduce dryer length by 50% and gas consumption by 25%.