Production and changeable law of O₃ purified by purifier of low temperature plasma

  Objective   To oserve the production and changeable law of O₃ when hazardous gas is purified by the purifier of low temperature plasma.

  Methods   In the pressure-tight experimental cabinet which volume is 40 m³, the changeable law of O₃ is observed which is produced by low temperature plasma and measured every 2 hours in 8 hours; Certain concentration of hazardous gas is prepared in the pocket which concentration is measured 1 hour before and after purification so that the purification efficiency can be calculated.

  Results   The wind rate of the outlet of the purifier on the high level is 0.84, 0.33 m/s on 100 cm, 0.05-0.33 m/s on the midde and low level.The purification effect is relativey good towards sulfuretted hydrogen, oxide of hydrogen, formol and sulfuric dioxide which purification efficiency is higher than 95%, but the purification efficiency of benzene series is lower than others, which is 27%-40%.In spite of the purification time increasing, the concentration of O₃ keeps relatively stable.The difference of the concentratons of O₃ between Ⅰ and Ⅱ level is 23%-33%;There are some significant differences between the concentration of O₃ caused by three different level.The concentration of O₃ of the outlet is higher than others, which is 0158-1105 mg/m³.

  Conclusion   Low temperature plasma has a obvious purification effect towards sulfuretted hydrogen, oxide of hydrogen, formol and suluric dioxide, which purification efficiency is higher than 95%;The concentraton of O₃ of the outlet is higher than others, which is much higher than "limit of permissible cncentration of indoor air pollutant", but the indoor average concentration of O₃ in 8 hours is 0.12 mg/m³, which basically conforms to "limit of permissile concentration of indoor air pollutant", so some filtration measures towards O₃ from the puifier of low temperature plasma should be taken.