Shrinkage of digested sludge from gelatin production

ABSTRACT

This study evaluated the influence of temperature on the apparent density, porosity and shrinkage of sludge during drying experiments conducted in a drying oven, under three different temperatures. Also, the apparent density behavior and porosity during the drying were evaluated. The influence of temperature was evident in all evaluated parameters. However, the behaviors are distinct for each temperature range due the case hardening phenomenon. The volumetric shrinkage of the dimensions was correlated linearly by Perez and Calvelo modified model. During drying, the apparent density and porosity exhibited variations in behavior, related to drying rates and critical moisture content.

KEYWORDS:

• Apparent density
• kinetics
• porosity
• shrinkage
• sludge drying

Additional information

Funding

The authors acknowledge to CAPES (Coordination for the Improvement of Higher Education Personnel), CNPq (National Counsel of Technological and Scientific Development), and Araucaria Foundation by financial support.