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Published on: April 9, 2016
Sewer solids separation by sedimentation--the problem of modeling, validation and transferability
R Kutzner1, H Brombach, W F Geiger
1Urban Water Management, University of Duisburg-Essen, Universitätsstr. 15, 45141 Essen, Germany. ralf.kutzner@uni-essen.de
Summary
Deterministic models for sewer solids sedimentation in stormwater and combined sewer overflow treatment are not widely accepted in Germany. Research shows existing models fail validation, highlighting a need for improved sewer solids sedimentation and remobilization research.
Area of Science:
- Environmental Engineering
- Water Resource Management
- Urban Hydrology
Background:
- Sedimentation of sewer solids is crucial for treating stormwater and combined sewer overflows in urban systems.
- Deterministic models exist for this separation process, but face skepticism regarding validation and transferability in Germany.
Purpose of the Study:
- To assess the validity of skepticism towards mathematical models for sewer solids separation.
- To propose a framework for validating zero- or one-dimensional models used in stormwater and combined sewer overflow treatment.
Main Methods:
- Development of a validation framework for particle separation models.
- Application of the framework to critically evaluate published models on sewer solids sedimentation.
Main Results:
- None of the reviewed literature models for sewer solids separation passed the proposed validation criteria.
- Significant deficiencies were identified in the validation and transferability of current deterministic models.
Conclusions:
- The skepticism of German Water Authorities regarding current sewer solids sedimentation models appears justified.
- Urgent future research is required to enhance the understanding and modeling of sewer solids sedimentation and remobilization processes.
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