Thesis Summary:

In the first part of this work the comparison of two numerical methods for the resolution of a non-reactive sedimentation problem for sewage treatment plants (PTAS) with variable cross-sectional area is presented. The comparison is motivated by the difference in efficiency of both methods. We present simulations for tanks with different types of geometry and compare the approximate solutions obtained by both methods and a study on the convergence of both methods. In the second part, a reduced model for the batch reactive sedimentation process is presented, a numerical method is presented for the approach of the solution which involves ingredients developed for the non-reactive case. Simulations obtained from the numerical method proposed under different initial conditions are presented; Kynch test, Diehl test and test of overcompressed sludge. And a brief comparison of the behavior of nitrate degradation is shown for the simulations obtained from the Kynch test and Diehl test.

ISI Publications from the Thesis

Raimund BüRGER, Julio CAREAGA, Stefan DIEHL: A simulation model for settling tanks with varying cross-sectional area. Chemical Engineering Communications, vol. 204, 11, pp. 1270-1281, (2017).

Raimund BüRGER, Julio CAREAGA, Stefan DIEHL: Entropy solutions of a scalar conservation law modelling sedimentation in vessels with varying cross-sectional area. SIAM Journal on Applied Mathematics, vol. 77, 2, pp. 789-811, (2017).

Raimund BüRGER, Julio CAREAGA, Stefan DIEHL, Camilo MEJíAS, Ingmar NOPENS, Elena TORFS, Peter VANROLLEGHEM: Simulations of reactive settling of activated sludge with a reduced biokinetic model. Computers & Chemical Engineering, vol. 92, pp. 216-229, (2016).