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Recent Developments in Photocatalytic Water Treatment
Technology
In recent years, semiconductor photocatalytic process has shown a great potential as
a low-cost, environmental friendly, and sustainable treatment technology to align
with the “zero” waste scheme in the water/wastewater industry. The ability of this
advanced oxidation technology has been widely demonstrated to remove persistent
organic compounds and microorganisms in water. At present, the main technical
barriers that impede its commercialization remained on the post-recovery of the
catalyst particles after water treatment. This chapter reviews the recent R&D progresses of engineered photocatalysts, photoreactor systems, and process optimizations and modeling of the photooxidation processes for water treatment. A number
of potential and commercial photocatalytic reactor configurations are discussed, in
particular the photocatalytic membrane reactors. The effects of key photoreactor
operation parameters and water quality on the photo-process performances in terms
of mineralization and disinfection are assessed. For the first time, we describe how
to utilize a multivariable optimization approach to determine the optimum operation
parameter so as to enhance process performance and photooxidation efficiency.
Both photomineralization and photo-disinfection kinetics and their modeling associated with the photocatalytic water treatment process are detailed. A brief discussion on the life cycle assessment for retrofitting the photocatalytic technology as an
alternative waste treatment process is presented. This chapter delivers a scientific
and technical overview and useful information to scientists and engineers who work
in this field.
Introduction
Increasing demand and shortage of clean water sources due to the rapid development of industrialization, population growth, and long-term droughts have become
an issue worldwide. With this growing demand, various practical strategies and
solutions have been adopted to yield more viable water resources. The storage of
rainwater for daily activities and increasing the catchment capacity for stormwater
are just a few examples that could resolve the problems in short term. Water industries and governments in some arid areas with abundant sunlight, less rainfall, and
long-term drought have a challenge to seek viable water resources. It is estimated
that around four billion people worldwide experience to have no or little access to
clean and sanitized water supply, and millions of people died of severe waterborne
diseases annually [205]. These statistical figures are expected to grow in the short
future, as increasing water contamination due to overwhelming discharge of micropollutants and contaminants into the natural water cycle [272, 296, 327]. In view to
suppress the worsening of clean water shortage, development of advanced low-cost
and high-efficiency water treatment technologies to treat wastewater is desirable.
Recent Developments in Photocatalytic Water Treatment Technology
Recent Developments in Photocatalytic Water Treatment
Technology
In recent years, semiconductor photocatalytic process has shown a great potential as
a low-cost, environmental friendly, and sustainable treatment technology to align
with the “zero” waste scheme in the water/wastewater industry. The ability of this
advanced oxidation technology has been widely demonstrated to remove persistent
organic compounds and microorganisms in water. At present, the main technical
barriers that impede its commercialization remained on the post-recovery of the
catalyst particles after water treatment. This chapter reviews the recent R&D progresses of engineered photocatalysts, photoreactor systems, and process optimizations and modeling of the photooxidation processes for water treatment. A number
of potential and commercial photocatalytic reactor configurations are discussed, in
particular the photocatalytic membrane reactors. The effects of key photoreactor
operation parameters and water quality on the photo-process performances in terms
of mineralization and disinfection are assessed. For the first time, we describe how
to utilize a multivariable optimization approach to determine the optimum operation
parameter so as to enhance process performance and photooxidation efficiency.
Both photomineralization and photo-disinfection kinetics and their modeling associated with the photocatalytic water treatment process are detailed. A brief discussion on the life cycle assessment for retrofitting the photocatalytic technology as an
alternative waste treatment process is presented. This chapter delivers a scientific
and technical overview and useful information to scientists and engineers who work
in this field.
Introduction
Increasing demand and shortage of clean water sources due to the rapid development of industrialization, population growth, and long-term droughts have become
an issue worldwide. With this growing demand, various practical strategies and
solutions have been adopted to yield more viable water resources. The storage of
rainwater for daily activities and increasing the catchment capacity for stormwater
are just a few examples that could resolve the problems in short term. Water industries and governments in some arid areas with abundant sunlight, less rainfall, and
long-term drought have a challenge to seek viable water resources. It is estimated
that around four billion people worldwide experience to have no or little access to
clean and sanitized water supply, and millions of people died of severe waterborne
diseases annually [205]. These statistical figures are expected to grow in the short
future, as increasing water contamination due to overwhelming discharge of micropollutants and contaminants into the natural water cycle [272, 296, 327]. In view to
suppress the worsening of clean water shortage, development of advanced low-cost
and high-efficiency water treatment technologies to treat wastewater is desirable.
Recent Developments in Photocatalytic Water Treatment Technology