162
Nomenclature and Abbreviations
FO
Forward osmosis
MD
Membrane distillation
PTFE
Polytetrafluoroethylene
PVDF
Polyvinylidene fluoride
PP
Polypropylene
DS
Draw solution
FS
Feed solution
NOM
Natural organic matters
RO
Reverse osmosis
NF
Nanofiltration
LEP
Liquid entry pressure
MWCO
Molecular weight cutoff
J w
Water flux (L/m
2
h)
R%
Salt rejection %
Abstract Membrane distillation is a widely adapted thermally driven technology
that offers versatilities in desalination and wastewater treatment. The prominent
challenge for membrane distillation is membrane fouling and wetting that has
received amplitude of attention over the past few decades, but very few researchers
have explored the minimization of fouling-wetting phenomenon so far. This book
chapter specifically focusses on mechanism of fouling and wetting, achievable prevention techniques, and selection of key parameters of membrane properties, useful
in curtailing the concerns of membrane fouling. Even the role of hydrophobicity,
pore size, and thickness of membrane is discussed in this article. The book chapter
also illustrates the stages of membrane fouling and its harmful effects, fouling differences due to various sources of water, effects of operating parameters, fouling
prevention, and cleaning techniques. The mechanism of wetting along with degree
of wetting has been demonstrated thoroughly. Basically, this chapter provides a
detailed insight of various foulants along with fouling mechanisms in membrane
distillation process. The book chapter highlights a number of approaches on membrane fouling and wetting minimization including the pre-treatment techniques,
optimization of operational conditions, and utilization of superhydrophobic membrane in membrane distillation process.
Keywords Membrane distillation · Membrane fouling · Scaling · Wetting ·
Superhydrophobic membrane · Cleaning techniques · Anti-wetting · Wastewater
treatment
S. S. Ray et al.