Vacancy No. IAMT 04-22

IAMT 04-22 Master Thesis: Impact of osmotic backwash during solar irradiance fluctuations on Nanofiltration/Reverse Osmosis scaling

Job description

Decentralized directly coupled photovoltaic-powered Nanofiltrration/Reverse Osmosis (PV-NF/RO) systems are a promising solution for groundwater desalination in off-grid rural areas such as developing countries. In such systems, mineral scaling developing on membranes is a common challenge that results in loss of membrane performance and an increase in energy consumption. On the other hand, solar irradiance fluctuations cause non steady state operations that lead to the occurrence of direct osmotic backwash (OB). OB is a potential self-cleaning method to mitigate scaling and maintain membrane performance. The impact of OB on scaling during the solar irradiance fluctuations is to date unclear and will be the main purpose of this study.

The aim of this project is to carry out a range of scaling and OB experiments under variable solar irradiance fluctuation conditions to evaluate the cleaning effectiveness of OB as a self-cleaning method for mineral scaling.

The following specific tasks will be performed as part of the project:

  • Literature review on the topic (membrane scaling, cleaning methods for scaling, direct osmotic backwash mechanism, photovoltaic powered membrane system, etc.).
  • Prepare scaling solutions and perform scaling and OB experiments with a lab-scale macro cross-flow system powered by a solar array simulator (SAS).
  • Perform membrane autopsy (scanning electron microscope, deposited mass analysis) after scaling experiments to evaluate the cleaning effectiveness of OB.
  • Analyze experimental data and write/co-author a research publication (in English).
Personal qualification

Studies in Chemical/Process Engineering or equivalent (Uni, TH)

Basic knowledge in water chemistry, water treatment process, membrane technology. Evidenced writing skills in English language, ability to learn/use Origin Labs software for data analysis and graphing and Endnote for literature management, willingness to lead or contribute to the writing of a scientific publication.

Organizational unit

Institute for Advanced Membrane Technology (IAMT)

Starting date

as soon as possible

Contact person
Contract Duration

6 months

Contact person in line-management

For further information, please contact Yang-Hui Cai, email: or Prof. Dr.-Ing. Andrea Iris Schäfer, email:


Please apply by clicking on "Apply" below.

Recognized severely disabled persons will be preferred if they are equally qualified.