Numerical Study on Steady State Three-Dimensional Atmospheric Diffusion of Sulfur Dioxide and Sulfate Dispersion with Non-Linear Kinetics

SUMMARY The aim of the present work is to study the three dimensional, steady state atmospheric diffusion equation for sulfate with its formation by conversion of sulfur dioxide (SO2) and removal by wet and dry depositions under the general Michaelis—Mcnlen process. The equations governing the non-linear diffusion process are numerically solved using an alternating direction implicit finite difference scheme. It has been shown that in the case of wet deposition, the percentage decrease in sulfate level is rapid over the range 0 < X ≤ 0.67 (X = dimensionless longitudinal distance) as compared to that of the case of dry deposition. Further, sulfate levels remain higher at ground level for X = 1.0 but its levels remain lower at ground level for X = 0.3 and 0.1. Wet removal is found to be more dominant than dry removal in the far off regions of the point source. The fallout of deposits is significant near the source and at the far off lateral distance.