技術論文
ハイボリウムエアサンプラ用の新たな直進型サイクロンの開発と評価
キーワード:
Forward Cyclone,
Dust Separator,
Particulate Matters,
PM2.5,
Respirable Dust,
High Volume Air Sampler
2017 年 32 巻 2 号 p. 112-117
詳細
2017 年 32 巻 2 号 p. 112-117
This paper describes a newly designed forward cyclone fitted to a high-volume air sampler (hereafter HV) of which flowrate ranged from 150 to 600 L/min. The cyclone-HV system is capable of sampling PM2.5 fractions of ambient aerosols and respirable particle factions (PM4) at work environments. The size separation characteristics of system were evaluated with two types of tangential-air-inlets of the cyclones (7 mm and 11 mm in width of the inlet). The size separation characteristics obtained for 11 mm inlet cyclone yielded 50% cut-off aerodynamic diameter Dp50 of 2.37 μm at the flow rate of 480 L/min, which is close to the size selection curve that required in the Japanese Industrial Standards Z8851. For the respirable fraction defined by ISO 7708 the same cyclone yielded Dp50 of 4.0 μm at the flow rate of 240 L/min. Dp50 and the size selection curve obtained for 7 mm inlet cyclone was also evaluated and the sampling of PM2.5 fraction for 3 hours were conducted ten times at Saitama, Japan, February 2015. PM2.5 concentrations measured by HV with 7 mm inlet cyclone and an automated PM2.5 measurement instrument utilizing beta attenuation showed a good correlation (r2 = 0.986).
