Atomiser centrifugal

Pressure used in pressure atomisers Centrifugal energy used in rotary atomisers Gaseous energy used in twin-fluid or blast atomisers... 

Venturi and orifice scrubbers are simple forms of wet scrubbers. The turbulence created by the venturi or orifice is used to atomise water sprays and promote contact between the liquid droplets and dust particles. The agglomerated particles of dust and liquid are then collected in a centrifugal separator, usually a cyclone. 

De-proteinisation of diluted whole blood, and acid extraction of lead from proteins with 2M HNOs is the preparation chosen for the National Bureau of Standards reference method for blood-lead analysis [28]. Centrifugation of blood samples treated in this way yields clear supernatant fractions that contain all of the lead present, and which are easily dispensed into electrothermal atomisers using auto-sampling techniques. This method gave results that compared very well with those obtained using anodic stripping voltammetry, r = 0.975, for concentrations of 10—900 pg l-1 of lead in blood [15]. 

Lead alloys (50 mg for flame analysis, 10 mg for furnace atomisation) can be dissolved in 1ml of distilled water with 0.5 ml nitric acid added. After warming, 5 ml of concentrated hydrochloric acid is added to dissolve the tin content, any precipitated lead chloride may be removed by centrifugation. Nickel, silver, tin and zinc may be determined in this solution using a conventional air/acetylene flame. Silver is usually the element of most interest in lead, but the proportion of tin in pewter is significant. The lead content can be determined in the original nitric acid solution but it is difficult to measure tin and lead in the same solution. 

Transfer 100 p,l of the blood sample to a polystyrene test-tube, add 150 p,l of water and 150 ]al of 2M nihic acid, mix vigorously for 30 seconds, centrifuge, and transfer the supernatant liquid into a 1-ml polyolefin cup. Introduce 10 p,l of this solution into die graphite furnace, dry, ash, atomise, and record die absorbance at 217 nm. 

The liquid is dispersed into the chamber either by centrifugal force or with a nozzle. Today centrifugal atomising is used much more widely as it offers the following advantages ... 

The characteristics of the powder on the other side depend on the speed of the liquid feed and the design of the atomising wheel. A centrifugal atomiser and its spray mist are shown in Fig. 2.55 and Fig. 2.56 [4],... 

Fig. 2.56 Spray mist from rotating wheel of centrifugal atomiser...

H. Li and X. Deng. Prediction of powder particle size during centrifugal atomisation using a rotating disk. Science and Technology of Advanced Materials, 8(4) 264, May 2007. 

Y. Zhao. Considerations in designing a centrifugal atomiser for metal powder production. Materials and Design, 27(9) 745-750, 2006. 

Atomiser. A device to produce a fine spray of small particles or liquid droplets. In a spray dryer, the atomiser may be a nozzle, or a spinning head which produces the spray centrifugally. 

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