Bioprocess Modelling (MLJ680)

The overall objectives of the course is to transfer knowledge on the principles of modeling and simulation of biosystems, and enable the engineer to construct models of biochemical processes carried out in activated sludge systems. In addition, techniques for calibration and verification of the biochemical models will be covered, and applications on simulation based design of carbon and nutrient removing activated sludge systems will be exemplified.

Course description for study year 2023-2024


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The course focus on mathematical modelling and simulation principles of microbiological processes, with emphasis on design and analysis of engineered systems such as wastewater treatment plants. Mathematical modelling represents a simplified image of complex systems with focus on the most important/dominating processes, and some simplifying assumptions. The most common modelling approach is the steady state assumption where input of mass is constant and reactions in the systems occurs at a constant rate, resulting in a constant output of mass from the system. Steady state is frequently used in design as the assumptions made have normally small effects on the final results. Steady state describes one specific situation and several calculations are normally done for one system to see effects of relevant variable factors, for instance water temperature.

To confirm the validity of the steady state calculation one move on to include variations in the input resulting in variable process kinetics and stoichiometry and a variable outlet regime, which requires a non-steady state modelling. The non-steady state modelling progress by defining an initial condition (for all variables) and perform successive calculations over small time steps to produce a dynamic (variable) response of the system reaction rates and final output. This approach requires computer calculation capacity and implementation of a computer program.

In this course, AQUASIM and SUMO will be introduced and used for dynamic modelling and simulations of aquatic systems. The program applies both to engineered systems (water and wastewater treatment) and natural systems (lakes, rivers and soil columns).

Learning outcome

After completing this course students should have aquired the following learning outcome, in knowledge, skills and competence:

  1. Principles for construction of biosystem models
  2. Using AQUASIM and the SUMO softwares as tools for modeling of activated sludge and biofilm systems
  3. Construction for multi-component models for activated sludge systems
  4. Calibration and verification of biochemical models
  5. Simulation based design of carbon and nutrient removing activated systems

Required prerequisite knowledge

MLJ610 Water and Wastewater Treatment


Form of assessment Weight Duration Marks Aid
Oral exam 1/1 Letter grades

The assessment will be based on a submitted modeling report prepared by the student on a given topic. The report will be assessed in a final oral examination.

Coursework requirements

Assignment reports must be submitted before oral examination.

Course teacher(s)

Course coordinator:

Ilke Pala Ozkok

Head of Department:

Ingunn Westvik Jolma

Course teacher:

Roald Kommedal

Method of work

Lectures 4 h/week. Exercises.

Open for

Admission to Single Courses at the Faculty of Science and Technology Environmental Engineering - Master of Science Degree Programme

Course assessment

There must be an early dialogue between the course coordinator, the student representative and the students. The purpose is feedback from the students for changes and adjustments in the course for the current semester.In addition, a digital course evaluation must be carried out at least every three years. Its purpose is to gather the students experiences with the course.


The syllabus can be found in Leganto