INDOOR PIEZOSORBTION SENSOR LIGHT OIL PRODUCTS LEAKAGE DETECTOR

Abstract

Background Oil and oil product spills cause significant economic losses and damage to the environment. The increase in the number of accidents in the production, transportation, storage and use of fuel for its intended purpose necessitates the development and implementation of leakage detection systems. The efficiency of such systems is due to the performance of sensors that detect specific changes in the environment parameters during fuel leakages. Aims and Objectives Development of the sensor light oil products leakage detector (gasoline, kerosene) in closed rooms and closed volumes (warehouses, fuel pumping stations), different from the existing ones in efficiency and ease of maintenance and characterized by high reliability, speed, selectivity, long «life». Methods The operation of the proposed fuel leak sensor is based on the principle of piezo-quartz microweighing, based on the transformation of the analytical signal resulting from the interaction of volatile fuel components with the sorption coating of quartz electrodes of the AT-srez, into a physical signal - the change in the oscillation frequency. As a sorption coating of piezoelectric quartz electrodes, multilayer carbon nanotubes (MCNTs) showing resistance to aggressive vapors of hydrocarbon fuel, high sorption capacity and the ability to regenerate were used. To improve the reliability of the fuel leakage detector and prevent false positives, two identical detection cells with modified multilayer carbon nanotubes (piezo sensors) were included in its design in parallel. The detection cells are located in the place of probable fuel leakage (joints of pipelines, joints of hoses) at a height not more than 15 cm from the floor so that the fuel vapors diffuse freely from the spill site into the near-sensor space. The signaling device of the sensor is triggered by the simultaneous and identical change of the analytical signals of two piezosensors. Results The piezosorption sensor is characterized by high reliability (the probability of false positives is not more than 1,5 %); speed (the time from the beginning of leakage to the decision by the operator does not exceed 20 seconds); independence of operation from changes in environmental parameters in a wide temperature range (from minus 5 °C to 35 °C). The «lifetime» of the piezosensor based on multilayer carbon nanotubes is not less than 2500 cycles of «sorption - desorption» of fuel vapor, after which it is easily replaced by a similar one. The sensor was tested in the laboratory of FSBIHC «The Center of Hygiene and Epidemiology» and applied for the monitoring of kerosene in the air station, pumping fuel at the airport to Primorsko-Akhtarsk.