Method and device for detecting the composition of gas mixtures

A method for detecting the composition of an unknown gas mixture (Minc) through an electronic nose (2) equipped with a measuring chamber (3) that houses at least one sensor, comprising the steps of:

• calibrating the at least one sensor by feeding a known gas mixture (Mn) into the measuring chamber (3);
• feeding the unknown gas mixture (Minc) into the chamber (3), while keeping the unknown gas mixture (Minc) in a predetermined desired state;
• detecting the composition of the unknown gas mixture (Minc) by means of the at least one sensor,
• wherein it further comprises steps of
• mixing the unknown gas mixture (Minc) with a cleaning gas mixture (Mp) to form a sample gas mixture (Mcamp) and
• regulating the state of the cleaning gas mixture (Mp) in order to keep the sample gas mixture (Mcamp) and hence the unknown gas mixture (Minc) in the predetermined desired state, in such a way as to keep the humidity of the sample gas mixture Mcamp, and hence of the unknown gas mixture Minc constant.

A device for detecting the composition of at least one compound in an unknown gas mixture (Minc) comprising:

• an electronic nose (2) equipped with a measuring chamber (3) that houses at least one sensor for detecting the composition of the unknown gas mixture;
• a system (18) for conditioning a cleaning gas mixture (Mp) that can be mixed with the unknown gas mixture (Minc) and designed to regulate the state of the cleaning gas mixture (Mp) in such a way that the latter reaches desired predetermined conditions;
• a junction (22) for mixing the unknown gas mixture (Minc) with the cleaning gas mixture (Mp), located upstream of the measuring chamber (3),
• the system (18) for conditioning the cleaning gas mixture (Mp) being designed to keep the humidity of the sample gas mixture Mcamp and hence of the unknown gas mixture Minc constant, to regulate the state of the cleaning gas mixture (Mp) in such a way as to keep the state of the unknown gas mixture (Minc) in desired predetermined conditions.