Measurement System for Characterization of Gas and Particle Phase of High Temperature Combustion Aerosols

Abstract

A measurement system was developed to sample and analyze the particle and gas phase of high temperature combustion aerosols up to a particle aerodynamic diameter of approximately 3 mm. The rapid changes of aerosol composition and concentration caused by the inhomogeneous fuel and changing burning conditions were accommodated by a combined measurement of both gas and particle phase and a synchronous measurement of two identical systems at two different positions at the boiler. Based on works reported earlier, an air-cooled dilution probe was designed and adapted to the corrosive composition of the combustion aerosol by use of a silica glass inlet and a ceramic porous tube diluter (PTD). Directly behind the probe, the raw gas is passing a cyclone which precipitates the coarse particles > 25 μm, and is then split into a gas analysis and a particle analysis branch. The particle branch, after further dilution and cooling to ambient temperature, is split for a simultaneous analysis by an APS and a low pressure impactor (ELPI or BLPI). The whole sampling line is conditioned to 300°C until final dilution and cooling to ambient temperature. The measurement system was employed at different incineration plants between 220°C and 950°C for various experiments, e.g., time resolved concentration analysis during soot blowing cleaning routine. The mass concentration balance, including the content of the inlet, achieved a 92% match of the total slag mass balance of the investigated plant.