Below we present a success story of a CO2 refrigeration project carried out in a renowned supermarket in Panama City.
by Duván Chaverra Agudelo
The refrigeration systems and their facilities have been presenting new technology alternatives that aim to improve the operability of the spaces and therefore the efficiency of the system so that the results are much more satisfactory for the client.
On this occasion we will present a success story on the provision and installation of a commercial refrigeration system made in Panama, more precisely in the new Riba Smith supermarket in Costa Verde located within the Market Plaza shopping plaza. Being a new store, the whole project was done from scratch.
The project consisted of the installation of the exhibition refrigerators in the different required models, the cold rooms with their doors and the refrigeration plant in subcritical CO2, which works in suscritical CO2 in direct expansion (DX) for the low temperature and in liquid CO2 pumped for the medium temperature. All this equipment was manufactured by Arneg Group in its factory located in Italy.
It should be noted that the installation was in charge of the company Crio who already have four installations of CO2 cooling systems in Panama for this same client (Riba Smith).
Technical description
It is understood that the subcritical CO2 system is ideal for large capacity installations in hot climates, offering substantial savings in energy consumption and providing a large volumetric cooling capacity with reduced refrigerant loads.
The system installed in the Riba Smith supermarket is of the waterfall type. Pablo Buchko, Central Director for America & Caribbean at Arneg Central America, commented: "The primary system consists of two R134a racks that are used only to cool the CO2 in the system to make it liquid. Then the average system uses a liquid CO2 pumping station (34barg/34barg) very similar to a glycol pumping system, but with the advantage that due to the volumetric cooling capacity of CO2 the diameters of the pipes, the dimensions of the pumps and evaporators are considerably smaller. The low-temperature system uses a directly expanding subscribed CO2 rack (10barg succ./28barg cond.) which also takes advantage of the larger volumetric cooling capacity of CO2 and uses smaller components than a system with common refrigerants (R404a/R507)."
Pablo added that "it is important to highlight that, although the dimensions of the system components (pipes, valves, compressors, pumps, evaporators) are reduced, the pressures of the system are considerably higher than those of a conventional refrigeration system. Therefore, operating pressures and temperatures must be taken into consideration during the design stage to select components that can withstand high CO2 pressures."
Meanwhile, to avoid difficulties during the realization of a project like these, Paul emphasizes the importance of selecting the right components so that the operation of the system is ideal.
"As in any engineering project, the right components must be chosen to ensure the operation and longevity of the system to be installed. This is of utmost importance in a CO2 cooling system. All components of the system must be made to withstand the low temperatures and high pressures at which CO2 circulates in the system. In addition, relief valves should be installed on the routes and safety valves to relieve the pressure of expanding CO2 in case electrical power is lost and the backup cooling system operating window is consumed."
Why CO2?
The installation of cooling systems with CO2 has been presenting more and more projects due to the different benefits in operation, efficiency and for being friendly to the environment due to not impacting the ozone layer. These and other reasons led Arneg and the company Crio to select this system for the supermarket.
"CO2 is a common, abundant and low-cost gas. CO2 having a minimal impact on the greenhouse effect is used as a reference with a GWP value equal to 1. In addition, it has no impact on the ozone layer (ODP=1). These characteristics classify CO2 as a natural refrigerant and make it a very attractive alternative with the new refrigerant restrictions that have been imposed worldwide for the care of the environment. By combining these characteristics of CO2 as a refrigerant with state-of-the-art technology developed by Arneg Group we can provide considerable savings to our customer in the operation of the system, since we have smaller components working on their points of optimal efficiency, "said the central director of the manufacturing company.
Results
As this is the fourth Riba Smith store in which the CO2 refrigeration system is installed, it shows that the project is being well received by the client, as Stated by Pablo Buchko in his final comments: "Our client is satisfied with the system, so this is the fourth store in which we install this technology. The customer is seeing great energy savings and the use of CO2 as a refrigerant positions them ahead of the market in terms of natural refrigerants and their adherence to new global regulations."
Overview
Installation signature: CRYO
Manufacturers involved: Arneg Central America
Company or place covered with the installation: Riba Smith Market Plaza
