Aerosol formation in a coal fired power plant plume

Abstract

In 1974 an instrumented aircraft was used to characterize SO/sub 2/, NOx, O/sub 3/, sulfate, and aerosols in the Labadie power plant plume near St. Louis, Mo. The paper deals with aerosol measurements. Volume flows of each pollutant were calculated from size distribution measurements, and wind velocities at each distance were measured. Tabulations (given in a table) show that although mean size increased from 0.24 ..mu..m at 10 km to 0.29 ..mu..m at 45 km, the size in the plume is not very different from the average for the upwind spiral. Volume flows (shown in a figure and table) show a 2 stage growth pattern; the growth rate increasing by a factor of 4 after 2 h., at a distance of 30 km. An alternative method used to show SO/sub 2/ conversion rate showed that 8 percent of the SO/sub 2/ was converted to aerosol at 45 km at a rate varying from 1.5 percent per h at 10 km to 4.9 percent per h at 45 km. Aerosol was 50 percent H/sub 2/SO/sub 4/ by weight at the relative humidity of 75 percent.