Water

Water purification via hollow fibre nanofiltration
(Joris de Grooth)

There is a growing need for novel water purification concepts based upon membrane filtration. Emerging pollutants such as hormones, antibiotics, bisphenol A etc., may over time cause severe health problems. Current water purification concepts, are not designed to remove these so-called endocrine disrupting chemicals (EDCs). Therefore a new membrane concept is required that can cope with these challenges while keeping a relatively high output. The present work focuses on the development of novel polymeric hollow fibre membranes based on new polymers.

Fouling removal by nucleated CO2 bubbles

(Al-Hadidi, Dr. A.M.M. (Abdulsalam))

Spiral wound RO and NF membrane elements are widely used in the desalination of water. Due to particle fouling and biofouling, part of the feed spacer will be blocked. Consequently, part of the membrane will be inactive and the impact of concentration polarization on module performance will be greater. Reducing the effect of fouling on membrane system productivity by nucleation of CO2 bubbles in the feed spacer was introduced as a new and effective cleaning system. In this project, the cleaning efficiency of nucleated CO2 bubbles in spiral wound elements will be investigated using flat cells in different orientations. Besides that, the effect of having a number of elements in series, the optimum operation parameters, the effect of the cleaning direction and flow speed will be investigated.

Nanofiltration concentrate treatment

(Christina Kappel)

The major bottleneck of the use of nanofiltration on municipal WWTP effluent is the concentrate stream. One option is to recycle the complete concentrate stream back to the start of the wastewater treatment process. Most important, these high loaded concentrate streams give new opportunities to recover compounds and produce pure products in intermediate treatment steps. The removal of phosphates for example is one of the treatment possibilities to recover fertilizers from a concentrated waste stream. This work focuses on optimizing the MBR process, the NF step and the compounds recovery.

Nanoparticle filtration (Krzysztof Trzaskus)

A rapid development of nanotechnology in the last few years resulted in an exponential growth of the global production of nanomaterials. There is much information available about advantages of nanoparticles (NPs). However, there is no wide knowledge about their destination and health effects after the usage. It is expected that water systems will be contaminated by nanomaterials which can cause a significant problem in the future. To reduce the amount of NPs in aqueous systems, membranes are proposed to remove them. Therefore, an investigation on the stability of NPs in water as well as their filtration behavior is carried out. This project focusses on the fouling behavior of a membrane during the filtration of nanoparticles.

Air Sparging in Reverse Osmosis modules

(Yusuf Wibisono)

Reverse osmosis (RO) is increasingly used in drinking water treatment, seawater desalination, wastewater reclamation and for the production of water for industrial purposes. However, the key problem is membrane fouling. The work has the aim attention to investigate air/water two phase flow dynamics in vertically positioned RO membrane modules and to improve its efficacy in relation with different process variables to remove biofilm and particulate matter from fouled spiral-wound membrane elements.