How to protect the lens in the online particle size analyzer from contamination when using the dry method?
When using the dry method for introducing samples in online particle size analysis, the protection of the lenses from contamination caused by sample particles or dust is essential. The protection is achieved by two different methods, namely, the utilization of a sheath gas and a dual air curtain.
The sheath gas is emitted through the peripheral channel of the sample nozzle, which provides stretching and focusing force on the sample jet, restricting the movement of particles to the optical lenses.
The effect of the dual air curtain system is to generate positive stress zones. The application of the air curtain ensures that the lenses are fully protected and that the sample accurately passes the measurement zone. The result is, therefore, more precise, with little to no contamination of the lenses by sample particles or dust.