Absorptive refrigeration
Unlike conventional industrial refrigerators, the cooling unit at L’Italiana Aromi works by absorption, i.e. it does not use electric energy, but heat. Fed with hot water and working with a water-lithium bromide solution, the cooling unit used at L’Italiana Aromi, therefore, does not have a compressor, but is equipped with an internal system composed of absorber, heat exchanger and generator. In this way the thermal energy that is produced by the cogenerator is used also for the production of refrigeration energy, avoiding the consumption of additional electric energy. To sum up: refrigeration unit model LWM-W008; type of single-stage refrigeration unit using hot water, refrigerating power yield 255 kW.
Cooling with ground water
Using ground water directly, the consumption of electric energy is avoided for the production of refrigerated water with the aid of conventional refrigeration units. The air treatment unit for the air-conditioning of the building used for industrial production has two batteries fed with ground water, which act as a support to two batteries fed with refrigerated water, coming from the plant with heat pump and trigeneration. These batteries allow a partial or total cooling – depending on the temperature of the air outside – using ground water at 12°C, with no expenditure of energy apart from that used by the pumps which allow circulation to take place. Production of refrigeration energy; water at 12°C; airflow treated 43350 m3/h; refrigeration power yield 102 kW.
100% automated process
The method of management used for the production processes, the supply and transfer of energy is also cutting-edge. The system is, in fact, totally automated and can be configured according to the different needs of L’Italiana Aromi. The efficiency of the energy-saving system is driven by a single PLC, a single industrial computer installed in the control panel of the thermal/electric power plant which controls all plant machinery. It deals with optimising the thermal energy produced by the co-generator, storing the process data and displaying alarms should there be any anomalies in the system. From his own computer, then, every inspector can configure the system according to company needs, selecting the production of hot or cold water.
Table 3 – Minimum benefits of the geothermal system combined with the cogenerative system
Reduction in the energy bills by 35 %
Saving of tons of oil equivalent to 173.62 TOE/year
Avoided emission into the atmosphere of CO2 equal to 721.20 tons/year
Avoided emission into the atmosphere of NOx equal to 630 kg/year
Avoided emission into the atmosphere of SO2 equal to 1,150 kg/year
