Mantova, Italy – September 2022

The new distribution center for Rossetto SpA was built in Mantova, Italy.

Enex has designed and supplied the refrigeration units for the almost 90.000 m3 building.

The distribution center has a total requirement of circa 2,0 MW for medium temperature use and 500 kW for low temperature. It is one of the biggest in Italy and it was installed by SCAR refrigeration (Milano).

Due to large size of evaporators for LT it was a specific request from the Ownership to limit to a minimum the electric energy consumption, also during defrosting.

Enex developed a new circuit design, the first example of hot gas defrost with total heat rejection in a transcritical system with CO₂, which was thoroughly tested before being installed at the customer’s site.

The results were beyond the expectations: extremely fast defrosting, low energy consumption, stable temperature in the refrigerated cold rooms, no thermal stress on the piping and on evaporators due to low operating temperatures and finally extreme reliability of the system.

The “warm gas” defrosting was not the only innovation of the system. Together with installer a series of control procedures were developed to further minimize the energy consumption and to manage properly the system.

All the solutions developed by Enex since 2014 to maximize efficiency were implemented:

  • Liquid ejector
  • Parallel compressors
  • Expansion energy recovery with ejectors
Number of units3
Number of compressors MT per unit6
Number of LT compressors per unit4
Number of auxiliary compressors per unit2
Total net capacity for each unit600 kW MT / 200 kW LT

The system installed is, still in 2022, the state-of-the-art refrigeration system, and more of these systems are under construction.