SETTING UP AND EVALUATING AN AERATION SYSTEM WITH ARTIFICIALLY COOLED AIR

Abstract

The aeration system is used to preserve the quality of the stored grains, with the main objective of cooling the grain mass. Despite being the most widespread system for preserving stored grains, aeration has limitations such as dependence on local climatic conditions. Therefore, the cooling system can be an alternative technology to replace conventional aeration.  The objective of this work was to design, construct and evaluate an artificially cooled grain aeration system. A prototype silo with dimensions of 0.9 m in diameter and 3 m in height, with a perforated bottom, was built, and an artificially cooled aeration system was adapted, in which the vortex tube coupled to the side of the plenum was used to blow the cold air. In the recording of temperature and interstitial moisture data of the grains; and the temperature and humidity of the environment, SHT75 sensors were used that were placed in the center of the prototype silo. The vortex tube was activated 15 minutes before turning on the fan, so that the temperature of the air blown by the fan in the silo was lower than the temperature of the ambient air. The artificially cooled system was activated daily at 7 pm and turned off at 8 am. In the evaluation period, the air temperature did not present major variations, ranging from 20.97 to 26.56ºC, on the other hand, the relative humidity of the air suffered large oscillations from 81.13 to 34.78%. The evaluation time was 26 days and the average temperature recorded at the end of the experiment was 24.02ºC. The artificially cooled aeration system worked correctly, reducing the temperature of the aeration air, but only with one compressor it showed low efficiency.

DOI:https://doi.org/10.56238/sevened2024.028-001