The main focus area is flocculation, filtration, drainage, e.g. for sludge dewatering, treatment of lake sediment, recovery of phosphorus from wastewater.

We have in our laboratory methods for characterizing feed suspensions e.g. for extracting and analyzing extracellular polymeric substances (EPS) from activated sludge, measuring floc strength and particle charge. One group of particles that often causes problems in separation is colloidal particles, which are small particles with diameters ranging from 1 nm – 1 µm. Colloidal particles have a large surface area and surface properties of the colloidal particles are therefore crucial for separation. We synthesize colloidal particle to study how surface charge, particle softness and hydrofobicity effects the membrane filtration process. Based on these results we have developed new mathematical filtration models for simulating dewatering in dead-end filtration and membrane fouling in cross-flow filtration.