Method and apparatus for analysis of particulate content of gases

摘要

Method of analysis of particulate content of gases, applicable to the quantitative and qualitative analysis of vehicle engine emissions and otherwise comprises sampling, removing particles and analysis of the removed particles. Sampling is effected by electrostatic precipitation using a catalyst-coated piezo-electric crystal. The analysis of the removed particles is effected by heating the crystal in an oxidising atmosphere to oxidise the deposited particles. Connection of the crystal to an oscillation circuit enables the frequency of oscillation of the crystal to be monitored. Changes in the frequency of oscillation are interpreted to provide quantitative and qualitative analysis of particles deposited and subsequently oxidised. <IMAGE>