On time discretizations for the simulation of the settling-compression process

The simulation model for secondary settling tanks by Burger et al. (2013) was introduced mainly to resolve spatial discretization problems when both hindered settling and the phenomena of compression and dispersion are included. Straightforward time integration unfortunately means long computationaltimes. The next step in the development is to introduce and investigate time-integration methods for more efficient simulations, but where other aspects such as implementation complexity and robustness are equally considered.The key findings in this work are partly a new time-discretization method, which will be introduced at the conference, and partly its comparison with other specially-tailored and standard methods. Several advantages and disadvantages for each method are given. One conclusion is that the new method (LI) is easier to implement than another one (SI), but less efficient (based so far only on batchsedimentation tests). (Less)