Otimização da performance de congelamento de produtos frigoríficos em túneis contínuos

Abstract

The aim of the present work was to evaluate the ineffectiveness of the freezing tunnels refrigeration system from the frigorific of city of Chapecó/SC, as well as to propose an effective solution to reduce this inefficiency. This company unit has 07 continuous freezing tunnels of TRV type, which are developed to work with forced convection heat transfer principle. Therefore, there are pasteboard packaging containers for transporting the product during the tunnels crossing. These packages enable the passage of air through their walls, which have specific openings for this purpose. The icy air surrounds the accommodation region and comes into direct contact with the product by withdrawing the thermal energy stored in it through convection. However, the related company chose not use the recomended packaging, and in its place implanted a model of cardboard boxes without openings in the walls. For this reason, the air cannot circulated through the product, being limited to direct contact over the packing bottom and side. The methodology proposed and validated in this work, promoted a reduction of 50% in the energy consumption, by reducing the freezing time and increasing the efficiency of the refrigeration system by the packaging replacement. It was proposed to replace the pasteboard packs with HDPE packages with cast walls to maximize the efficiency of the heat transfer process by forced convection. This proposal was tested by means of a case study, through physical tests on product freezing process, and it was proved an increase in energy efficiency of over 74%. The energy efficiency maximization is mainly due to a packaging prototype developed specifically for the evaluated process.