Study On Air Disinfection Test Of Ozone

Objective To investigate the effects of different conditional parameters on the efficacy of ozone air disinfection.Method To measure the ozone concentration in a 20m~3 aerosol chamber with 49C ozone measurement instrumenets and then compare the efficacy of ozone air disinfection under different conditional parameters such as temperature , relative humidity, spray pressure, organic content in microorganism aerosol, static condition, dynamic condition, staphylococcus albus(8032), staphylococcus aureus(ATCC6538), haemophilus influenzae(02010).Results (1)The ozone concentration in aerosol chamber can be changed significantly by different relative humidity(P<0.01) .(2) The compositions and the diameter of microorganism aerosol can be changed significantly by sprays pressure and concentration of organic matter in microorganism aerosol (P<0.05) .(3)Under the static condition, the airborne bacteria elimination rate can be changed significantly by different relative humidity and different organic matter in microorganism aerosol (P<0.01) . (4)The airborne bacteria elimination rate can be changed more significantly under dynamic condition than that of static condition (P<0.01) .(5) The efficacy of ozone air disinfection air can be affected significantly by relative humiditiy(P<0.01) and air temperature (P<0.01) , and also can be affected significantly by the interaction between air relative humidity and air temperature (P<0.05) . (6)For bactira staphylococcus albus (8032), staphylococcus aureus (ATCC6538), haemophilus influenzae(02010), the efficacy of ozone air disinfection was significantly different (P<0.01) .(7)An ozone generator with 1.5908 g/h output can remove 99.90% airborne bacteria in average in 20m~3 aerosol chamber after 10min ozonation by similar field test, while it can remove 90. 00% airborne bacteria in average in 100 m~3 room after 60min ozonation by static field test.Conlusion (1) The relative humidity may have negative correlation with the ozone concentration. The ozone concentration in the air can't reflect the production capacity and the disinfection ability for an ozone generator. (2)The ozone diffusion in air has a negative correlation with the relative humidity. (3) After generating by ozone generator, the ozone concentration in the chamber can increase continuously to one level and then keep above an effective level for some time. So the time for generating and maintenance of disinfection are very important disinfection indicator. (4)The change of the sprays pressure and the organic matter in microorganism aerosol can affect the composition of artificial microorganism aerosol. (5) Under the static condition, the natural elimination rate of microorganism aerosol can be affected by the relative humidity and the organic content of microorganism aerosol, this rate can decrease when the relative humidity is 60±5% and so can it when there is orgnic content in the microorganism aerosol. (6) The natural elimination rate of microorganism aerosol is lower under dynamic status than under static status. (7) The relative humidity and the temperature have a positive correlation with the efficacy of the ozone air disinfection over a limited range. (8)The resistance of the strains in microorganism aerosol to ozonation is rated as followed: haemophilus influenzae(02010)>staphylococcus albus(8032)> staphylococcus aureus(ATCC6538).Creativity and Significance This project revealed that ozone was one of disinfection factors. For the ozone air disinfection test, the atmosphere temperature, the relative humidity, spray pressure, organic content in microorganism aerosol, static condition, dynamic condition and diffirent reporter bacteria strains can affect the efficacy of the disinfection. It also indicated that the ozone concentration in the air cannot be used as the unique evaluation indicator for the generating capacity and the disinfection ability of an ozone generator. The relative humidity and the organic content in microorganism aerosol and dynamic condition such as air agitation can be the impact parameters for the natural elimination rate of microorganism aerosol.