Researchers from the Polytechnic University of Valencia (UPV) develop a new refrigeration system that allows the storage and transport of vaccines against covid-19 that require very low temperatures, since the system is capable of reaching up to 200 degrees below zero.
The Autonomous Ultra-cold Container-CAU is scalable for all types of cameras, from the delivery vans of medical-pharmaceutical material, to industrial refrigerators, large containers of goods or in logistics storage and distribution centers.
The system, developed by the CMT-Motores Térmicos of the UPV and that reaches -200 degrees centigrade stable, exclusively uses ambient air as a refrigerant and is 100% self-contained with electrical power, as reported by the academic institution.
“With the we could cover the whole processor both transport and storage of vaccines, ensuring at all times that the chambers are kept at the required temperature to guarantee their correct conservation “”, highlights Vicente Dolz, researcher at the UPV’s CMT-Thermal Engines.
An alternative to dry ice
The latest technologies applied to the manufacture of vaccines involve the conservation of genetic material of the virus at cryogenic temperatures (-70 ° C). The solution today is to use dry ice, which sublimates at -78ºC, or liquid nitrogen, which evaporates at -196ºC., to refrigerate vaccine containers.
However, according to the researchers of the CMT-Thermal Engines of the UPV, this technology has some drawbacks, since not easy to control temperature and light bulbs, and if they are subjected to too extreme temperatures they can be damaged. In addition, in certain transports such as aircraft, the CO2 from dry ice that sublime in the cabin It could be dangerous and, in addition, a lack of supply of dry ice is expected due to the shortage in production of pure CO2.
“The current health emergency situation and the new vaccine manufacturing techniques require new cooling techniques at very low temperatures“, highlights José Ramón Serrano, researcher at the UPV’s CMT-Thermal Engines.
According to Serrando, the industrial and fiscal limitations for the manufacture and commercialization of traditional refrigerant fluids make it necessary to look for new efficient ultra-refrigeration technologies, but at the same time respectful with the environment and that minimize CO2 emissions. “It is to this need that the system that we have devised in our laboratories responds,” he asserts.
In order to maintain the cold chain in the transport of vaccines, the air expansion in a reverse Brayton cycle. And by controlling the rotational speed of the cycle compressors, with a frequency variator, the power and therefore the process temperature is controlled “, he explains.
As the vaccines already arrive inside insulated boxes loaded with dry ice, the CAU only maintains the cold chain by compensating for heat losses to the environment. This allows the indefinite storage or transport of the vaccine boxes, inside the CAU chamber, and without the need to replace or monitor the dry ice. “You just need to provide power to the machine. It could also be an alternative to dry ice if the CAU is used directly to store the vaccines in the production center, “” Serrano concludes.
The CMT-Thermal Engines team of the UPV has a prototype of the CAU instrumented and in operation in one of the test benches of its laboratories.