If fruit and vegetables are stored in a refrigerator cell for preservation, oxygen O2 is consumed and therefore carbon dioxide CO2 rises, as a consequence of respiration. An excessive concentration of CO2 causes irreparable damage to the goods. With the adsorber of carbon dioxide one aims at eliminating the excessive CO2 and adding the necessary oxygen at the same time.

WORKING CRITERIA OF THE MACHINE

The cell’s air, containing CO2, will be sucked by a compressor, filtered in a special tank containing activated carbon and then reintroduced to the cell. The carbon, trapping CO2, will be saturated gradually. This procedure is called adsorption. Subsequently, the compressor conveys fresh air to the tank, which separates CO2 expelling it to the outside. During this phase called regeneration, the circuit of the machine separates from that of the cell, while avoiding the introduction of fresh air. The sequence of the operations is completely automatic and depends on a system program.

By means of a special circuit, interlocked by three-way valves operated pneumatically, it is possible to raise the oxygen level in the cell upon simple electronic request from outside. By means of the valves, the adsorber is able to totally eliminate the oxygen in the air, used in the regeneration phase.

ADVANTAGES OF THE ADSORBER

The system of oxygen elimination in the regeneration phase offers the possibility to reach very low U.L.O. in the cell (Ultra-Low Oxigen). The advantage of this type of machine lies in the fact that there are no motorized valves near each cell and therefore no electric connections. The pipes between machine and cell are markedly reduced, since the machine can be installed close-by. The probability of failure is almost zero. Each cell works independently. It is also possible to automatically command more adsorbers by means of an automatic analyser.