This work presents a generalized tool for modeling precipitation processes for the parallel formation of multiple solid phases. A symmetric mixing model for T-mixers is presented which mimics the mixing process in a numerically highly efficient way. This model can easily be extended to other reactor types such as stirred tank reactors following the implementation given in this work. Modelling ion activities and ion complexation is strongly accelerated by the analytical formulation of the Jacobian of the corresponding system of equations. Solid formation processes are described via the numerically efficient Direct Quadrature Method of Moments (DQMOM) which is parallelized for treating multiple solid phases simultaneously. Expressions for agglomeration of multiple solid phases and for particle transfer between different mixer zones are given. Both the models of the individual processes and the entire precipitation tool are validated and tested in multiple scenarios proving the flexibility of the tool. (C) 2016 Elsevier Ltd. All rights reserved.