Apparatus for alternatives to PM-10 sampling

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:166572

Wente, M; Wente, W E ^[1]; Moore, M E ^[2]

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1. Texas A&M Univ., College Station, TX (United States)
2. Los Alamos National Lab., Los Alamos, NM (United States); and others

Because of questions of whether PM-10 adequately characterizes the size fraction that is a challenge to human health, we have developed devices and samplers that will provide PM-2.5 and PM-1 size fractions. Each of these systems utilizes a cyclone for the fractionation process. Models have been developed to predict both the cutpoint and the fractional efficiency curves for single inlet cyclones are geometrically similar to a form that was utilized by Lapple. Modeling has been done with two geometrical forms of multiple inlet cyclones. Each form has six inlets, and one form has the body shape of a Lapple cyclone, while the other has a shortened body. The models for cutpoints are based on log-linear correlations between D{sub 0.5}/d{sub o} and a flow Reynolds number; where D{sub 0.5} = cutpoint size, d{sub o} = cyclone body diameter, and the flow Reynolds number is based on the inlet velocity and the outlet tube diameter. PM-1 and PM-2.5 fractionators with flow rates of 16.7 L/min have been tested in both laboratory and field environments. One version of the fractionator is a stand-alone cylone that has been commercialized by URG, Inc., and a second version is made as an adaptor to the Graseby Andersen Inc. Model 246 inlet for the dichotomous sampler. A third version of the PM-2.5 inlet is one that includes its own wind speed decelerator, bug screen and cyclonic pre-fractionator, where the latter device is used for reducing the aerosol mass that will be deposited in the PM-2.5 cyclone. A prototype field sampler has been developed that incorporates flow control, and a easily changeable filter cartridge.

• OSTI ID: 166572
• Report Number(s): CONF-9510126--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROSOLS
AIR POLLUTION MONITORING
AIR SAMPLERS
COMPARATIVE EVALUATIONS
CYCLONE SEPARATORS
FRACTIONATION
PARTICLE SIZE
TECHNOLOGY ASSESSMENT