In most large coal-fired power plants an absorption process with a limestone suspension is applied today. The flue gas proceeds upwards through a series of spray headers that introduce a uniform liquid flux of droplets of the limestone suspension. These droplets resist the gas flow and provide a large mass transfer surface area required for the SO2 removal process. During the spray overlapping the collision of the droplets may lead to a coagulation or a separation process depending on certain collision parameters, such as surface tension, impact velocity and collision geometry. A model for droplet collisions was developed and implemented in a two-phase flow simulation by Euler-Lagrange. The model is based on experimental investigations with overlapping sprays.