Chapter 2: Forward Osmosis for Application in
Wastewater Treatment
In Chapter 2 an overview of FO work performed
with impaired waters and waste streams is
established. This overview attempts to define the
steps still required for FO to reach full-scale
potential in wastewater treatment and water
reclamation by describing and discussing the current
developments, bottlenecks and future perspectives of
FO technology in the wastewater sector.
Chapter 3: Zwitterions as Alternative Draw
Solutions in Forward Osmosis for Application in
Wastewater Reclamation
Chapter 3 presents a study on several naturally
occurring zwitterions to find the ideal draw solute to
enhance FO performance, minimise solute loss and
enhance energy production in wastewater
applications.
Chapter 4: EDTA: A synthetic Draw Solution for
Forward Osmosis
Chapter 4 continues with the experimental work
mentioned in Chapter 3, employing larger molecules
as potential draw solutes for FO.
Chapter 5: Water Recovery and FO Membrane
Fouling
In Chapter 5 the effectiveness of FO membranes in
the recovery of water from sewage is evaluated,
focusing on membrane performance and fouling of
the FO membrane. Investigations were carried out
via short-term lab-scale experiments.
Chapter 6: Polysaccharide Dominance in FO
Fouling Studies of Raw Wastewater
Chapter 6 deals with the effects of fouling presented
in Chapter 5. Additional long-term studies were
performed and the fouling layers were extensively
analysed.
Chapter 7: Continuous and Discontinuous
Pressure Assisted Osmosis (PAO)
Chapter 7 focuses on improving water flux
performances by adding hydraulic pressure to the
feed side of the membrane process. An FO transport
model was also developed, incorporating the
additional hydraulic pressure to describe and
validate the experimental fluxes.
Chapter 8: A Technical Economic Assessment of
Sewer Mining using Forward Osmosis
In Chapter 8 the FO transport model mentioned in
Chapter 7 together with an existing ICP model was
used to predict mass transfer in larger scale FO
membrane installations and to develop and describe
the economic aspects of both a general FO-RO
process and more particularly, for the case of the
Sewer Mining concept.
Chapter 9: Conclusions
Chapter 9 provides the reader with the main overall
conclusions of this thesis. These conclusions view
this work from a broader perspective and offer
recommendations for future research.