Rotary impactor head
1Pages

Immission Line 2.223.01 Sampling accessories Useful for PM10 samplings; ideal for PM2.5 and PM1 sampling campaigns. Working principle The air flow is conveyed through the acceleration nozzles and then directed against a rotary impactor disc, coated with low-volatile mineral oils. Depending on the cut size diameter (PM10, PM2.5, PM1), the particles with a larger diameter than the programmed one collide with the impactor disc and stop there. The impactor disc rotation on the axis of symmetry of the multi-jet impactor allows to increase the particulate matter deposition surface, making considerably slower the accumulation process and the progressive impoverishment of the grease film covering the impactor disc. Therefore, the granulometric cut efficiency is kept constant for a longer time compared with the traditional sampling inlets. The Rotary Impactor Head allows to overcome the limits of the standard sampling inlets, where the particles progressive accumulation on the impactor disc gradually modifies the characteristics of the impactor disc itself, causing an high and rapid reduction of the cut size efficiency and therefore calling for frequent cleaning interventions. Standard multi-jet impactor impact disc impact surface of a single nozzle with circular section On every accumulation point corresponding to the single nozzle, the particles tend to settle on a larger and larger spot on the flat impact surface, until the stream will resuspend particleswith a diameter higher than the cut size. In these conditions, the impact does no more take place on a greasy anelastic surface and the particles are free to bounce off the already accumulated material. Rotary Impactor Head impact disc impact surface distributed for all acceleration nozzles The slow impactor plane rotation allows to present constantly to the flow coming out from the nozzles an impact surface anelastic, plane and as poor as possible in accumulated material. So the particulate matter accumulates on a circular crown distributed on the rotary impactor disc surface. That allows to keep the optimal conditions for the particulate matter capture for a time remarkably longer, drastically reducing the frequency of the interventions needed for the impact plane cleaning. Ed. 0 11/11 - Technical specifications may change without previous warning The new Rotary Impactor Head guarantees a very high quality standard in the PMx sampling with multi-jet inertial impactor. In particular it allows: • a definite improvement of the temporal stability of the granulometric cut size efficiency • a remarkable increase of the usable deposition surface (about 6 times larger in case of sampling inlets with 8 nozzles, in compliance with the European Standard) • a drastic reduction of the frequency of maintenance interventions needed for the sampling inlet cleaning. Product Data Immission Line 2.223.01 TECORA - Headquarter: 211-215 rue la Fontaine, 94134 Fontenay Sous Bois Cedex - FRANCE. Italian office: Via A. Volta 22, 20094 Corsico (Mi) - ITALY www.tecora.com Rotary Impactor Head