A procedure for defining bin size capable of treatment of bins consisting of 10(7) to 10(10) primary elements is defined. ?he application of these size classes in the numerical simulation of coalescence and breakage is described. The method is used to investigate the evolution of the particle size distribution for particles undergoing coalescence where the coalescence kemel have different functional form and where the initial condition may consist of either monodisperse particles or have a log normal distribution. The asymptotic behavior of the moments was examined. The second and third moments were found to approach asymptotic limits for a special class of kernels.