The main issue, for the purpose of introducing gas into the network (including biomethane), concerns odorization. In fact, for domestic and transport purposes, gases must have precise olfactory characteristics to guarantee the safety of users.
Determining the proper degree of odorization is thus most important. This activity is performed inside a rhino-analytic chamber, as specified by the UNI7133-3: 2023 standard "Odorization of gases for domestic use and similar - Part 3: Procedures for defining the olfactory characteristics of odorous fluids".
Rhino-analysis is the only acknowledged technique to verify the proper odorization properties of biomethane, according to the UNI 7133-2: 2019 "Odorization of gases for domestic use and similar - Part 2: requirements, control and management".
LOD rhino-analytical chamber, where analyses are performed, consists of a room of about 16 cubic meters, coated with aluminum, inside which a known quantity of odorant evaporates and mixes with the gas to be tested. Selected and trained examiners (rhino-analysts) go through the chamber and record their olfactory sensation according to the DecaSales scale. Then, the results must be compared with the odorization reference data.
In the case of biomethane, a sample is considered suitable for introduction into the network if:
•The smell intensity is greater than or equal to 4 olfactory degrees of the DecaSales scale;
•The conformity of the type of odor is recognized by at least 85% of the examiners taking part to the test (minimum of six).
LOD is the only private laboratory in Italy equipped with both an olfactometric chamber, according to UNI EN 13725: 2022, and a rhino-analytic chamber, according to the UNI 7133-3: 2023 Standard. It is therefore the only one in a condition to perform analyses in parallel and correlate the collected data according to both methods.
LOD also has the necessary skills to perform specific studies on elements potentially interfering with a proper odorization of biomethane (such as limonene, pinene and butanone).
