Facing the Sulfuric Acid Aerosol Problem in Flue Gas Cleaning: Pilot Plant Experiments and Simulation

Abstract

Experimental and simulation results of sulfuric acid aerosol formation during absorption of sulfuric trioxide in a wet flue gas scrubber (quench cooler) are presented. The complete characterization of the volatile aerosol with respect to number concentration and droplet size distribution is only possible by combining experimental and theoretical methods. Both experiments performed in a pilot plant and simulation results, reveal high number concentrations. A simulation tool predicts the formation of very small droplets that remain even submicron after coagulation in typical residence times of scrubbing systems and thus are difficult to precipitate.

Ultrafine particles over Eastern Australia: an airborne survey

“…3 showing the plume transect at about 130 km distance from Kogan Creek which equals approximately 8 hours of transport after emission. Primary particles are emitted at sizes of a few nm (Srivastava et al, 2004;Junkermann et al, 2011a;Brachert et al, 2013Brachert et al, , 2014. Observed growth rates derived from mean geometric diameter in the plume centre, an emission size of Â8 nm, and the travelling time from the source derived from HYSPLIT agree with those reported from previous ground based and airborne studies with an initial rate of Â3Á8 nm/h up to a diameter of about 25Á30 nm (Kulmala et al, 2004;Suni et al, 2008;Junkermann et al, 2011a).…”

“…3 and 4). Particle production via sulphuric acid is well known in the engineering community and is the cause of opacity at the chimney (Srivastava et al, 2004;Brachert et al, 2013Brachert et al, , 2014. However, the resulting particle emission or formation rate downwind of the chimney is not well known as airborne measurements are required (Pueschel and Van Valin, 1978;Whitby et al, 1978;Junkermann et al, 2011aJunkermann et al, , 2011b.…”

A wet electrostatic precipitator (WESP) as countermeasure to mist formation in amine based carbon capture

“…< 0.2 m) with number concentrations exceeding 1E8 cm −3 . This is in line with the simulations presented by Brachert et al (2013) investigating the aerosol formation during flue gas cleaning. The aerosols grow in size as they travel through the absorber through the taking up of water and amine to sizes close to but staying below 1 m. However, despite the fact that most of the aerosols (expressed in number concentrations) are well below 1 m, most of the water (and thus amine) is found in the aerosol sizes between 0.5 and 2 m. Therefore, if one aims at designing efficient countermeasures, eliminating this size fraction is crucial.…”

Ultrafine particles over Germany – an aerial survey

“…The resulting number concentration is in the order of 4 )10 7 cm (3 at the outlet of the stack after 20 s of coagulation independent of the emitted H 2 SO 4 concentration. Aerosol diameter in the AerCoDe B scenario is by far higher than observed (this study and Junkermann et al, 2011a) and modelled by Brachert et al (2013) at 50Á90 nm. Assuming an average volume flux for all considered combustion plants the source strength in scenario B of the direct particle emissions was prescribed to 5.5 )10 15 particles s (1 per plant.…”

“…The in situ measurements allow us to derive an approximate age of the aerosol based on the size of the Aitken mode. UFPs are either the result of gas-to-particle conversion with initial sizes of about one nm (Kulmala et al, 2013) slowly growing into the detectable sizes of !4 nm or primary emissions with sizes between Â6 and Â10 nm (Junkermann et al, 2011a;Brachert et al, 2013Brachert et al, , 2014. All these particles grow during the day in the atmosphere with a few nm per hour (Junkermann et al, 2011a;Kulmala et al, 2013) into size ranges of CCN !50 nm (Laaksonen et al, 2005;Andreae, 2009).…”