In this paper the authors describe an interactive virtual environment developed to model an emission reduction system for commercial boilers. The interactive environment is used to optimize the performance of the reduction system through the spatial adjustment and spray reconfiguration of reagent injectors. They describe the three principal components of the system: a computational model for the particle dynamics, a three-dimensional display device and graphics environment, and the communication layer that allows the interaction of the user in the visualization environment with the computational model. Timing results for each component are given for three hardware configurations that demonstrate the real-time performance of this tool.