Ing. Luca Laghi Direttore Tecnico della unità di efficienza energetica di Certimac Laboratorio presso ENEA Faenza
In the development process of some mask sanitization devices through dry heat source, once validation is completed, the sanitizing power against pathogenic microorganisms via heat treatment will occur. Therefore, it is crucial to optimize the system thermal behaviour in order to:
- Assure total efficiency of the process within the right time and temperature ranges, without altering the intrinsic properties of the PPE sanitization object;
- Maximizing the process efficiency in terms of reducing the cycle time and minimizing the total electricity consumption.
- An effective process starts with ensuring as much of an even distribution as possible in the chamber, namely with:
- Adequate sanitization of the chosen materials for the isolating “shielding” and for the side in contact with the test chamber;
- Proper dimensioning and correct distribution of heating elements (electric resistors) in the device volume;
- Appropriate inner temperature control system such as to monitor and ensure the preservation of the suitable sanitization conditions for the cycle timeframe, while protecting the qualities of the PPE.
An efficient process is actually based on:
- A careful selection of the isolating materials implemented in the chamber such as to maximize the degree of isolation, minimizing the shims and, therefore, the obstructions;
- Optimization in the arrangement of each component outside the chamber, which is to be placed so as to assure full functionality of the device without introducing thermal bridges in which isolation gets “interrupted”, with repercussions on the cycle efficiency and, secondly, on the overall consumption;
- Proper dimensioning of the electricity supply, ad hoc assessed and minimized so as to aim to the highest energy class.
In order to deploy the process which allows to maximize the device effectiveness and efficiency, analytic and theorical knowledge on the measuring techniques of the thermophysical parameters (thermal conductivity, specific heat) that characterize the concerned materials becomes necessary. Added to this is the functional expertise for the development of predictive calculation models which can allow to preventively evaluate and quantify:
- Punctual and global thermal behaviour of the device in its cycle phase;
- Thickness of insulation and materials;
- Layout and distribution of the various components;
- Identification of risky thermal bridge areas;
- The necessary powers to ensure the respect of the cycle timeframe at the targeted temperature, minimizing the overall consumption of the device.
The competencies and the activities described above constitute the key role of the CertiMaC research organism funded by ENEA and CNR and operating in the materials and energy efficiency science field, which has provided equipment and specialist skills in the thermophysical field for the industrial support of new devices.