RESUMO
An ozone concentration meter in ozonated water has been developed and manufactured. The measurement of ozone concentration is based on the use of a photometric method. The range of measured ozone concentration is varied from 0.1 to 10 mg/l. The principle of operation of the meter is based on recording the difference in the absorption coefficients of ultraviolet radiation by the analyzed ozonated water and the reference (ozone-free) water. The meter was calibrated on an automated measuring stand using a monochromator and a photomultiplier tube. Such a device could be very useful in water purification systems or wastewater treatment plants. The developed meter provided high accuracy and stability of readings, operation without maintenance, full automation of measurement, and automatic correction of zero drift.
Assuntos
Ozônio , Purificação da Água , Raios Ultravioleta , ÁguaRESUMO
A portable device for cleaning and ozone sterilization of small-sized delicate dental instruments that cannot withstand the high heat and humidity of standard autoclaving has been developed. The device contains a remote unit for magnetic mechanical washing, an ultrasonic bath for pre-cleaning treatment, and a container for ozone sterilization with a reactor based on dielectric barrier discharge. The maximum ozone concentration in water reached 8.5 mg/l for 10 min of operation at a water temperature of 19 °C. The results of inactivation of Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus are presented. Distilled water with such seeded micro-organisms was bubbled with an ozone-air mixture at an ozone concentration of 5.8 mg/l at 17 °C for 5 min, 10 min, 20 min, and 30 min. The maximum bactericidal effect was manifested for Pseudomonas aeruginosa cells with their total elimination within 10 min. Inactivation of Escherichia coli bacteria was monitored after 20 min of treatment, and Staphylococcus aureus-after 30 min of treatment.