Real-time optical fiber sensor for hydro-alcoholic solutions

The real-time determination of hydro-alcoholic concentration in alcohol distillation plants is a primordial condition in order to preserve the quality and reduce production losses. Presented research proposes a Fresnel reflectometric optical fiber sensor for the determination of hydro-alcoholic concentration in liquids. The intensity of reflected light and the sample temperature are continuously measured and processed by a fast algorithm. Calibration curves were prepared for a range from 0 to 100% of water in alcohol (ethanol) and adjusted to second order polynomials. According to functional tests, sensor provides maximal error of 1.3 % for concentration values and proportionates practically real-time analysis.