Environmental Engineering Reference
In-Depth Information
23
EnginEErEd nanomatErials for Purification
and dEsalination of PalatablE WatEr
Vijay C. Verma
1
, Swechha Anand
2
, Mayank Gangwar
1,3
, and Santosh K. Singh
2
1
Department of Microbiology and Infectious Diseases, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
2
Centre of Experimental Medicine and Surgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
3
Department of Pharmacology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
23.1
introduction
Water is a limited natural resource that is vital for life on earth, and the depletion and pollution of its sources further complicate
the seriousness of this problem. Despite the fact that more than 70% of the earth is covered by water, most of it is useless
because of its unpalatability. However, contamination of groundwater, which is a major source of safe drinking water, is
widespsread in many parts of the world. Clean water is a basic requirement for any society, and in recent years many parts of
the world have faced substantial increases in the demand-to-supply ratio of drinking water. The rate of global water consump-
tion is almost more than twice the rate of growth of the human population. According to the United Nations, approximately
1 billion people on the earth are facing severe scarcity of fresh drinking water, and if this situation continues, the demand for
freshwater will reach an approximately 56-fold increase by 2025 as compared to the present. Many strategic consultancies are
speculating concern over “water” becoming the cause of conflict and possible war in the future. To prevent these unpleasant
consequences, it is worthwhile using water wisely and promoting awareness for saving water in our society, apart from expe-
diting technological advancement for rendering surface water appropriate for drinking. Recent statistics show that in devel-
oping countries a number of people die annually due to consumption of unhygienic water and this number is even greater than
the lives lost in wars and violence combined. In the African continent, more than 5.7 million people lack access to safe and
hygienic water (Fig. 23.1), and about 20 million lack sanitation services [1]. As per the United Nations Millennium Development
Goals (UN-MDGs), access to safe drinking water, free from disease-causing bacteria and viruses, is a basic human right, and
essential to maintain a healthy society. The international community has committed to provide safe drinking water and accesses
to sanitation services by 2015. To achieve these MDGs, scientists are looking toward nanotechnology-enabled solutions. By
harnessing the unique and novel properties of nanoscale materials, they are trying to adapt them for water treatment purposes.
Nanotechnology offers great opportunity to refine and optimize current and future techniques of purifying water. Nanotechnology-
based solutions in the water sector will find wide applications if they are cost-effective, efficient, and able to provide clean
drinking water even in very remote parts of the world.
In this chapter, we try to explore the possibilities of sustainable access to safe drinking water by adopting cutting-edge tools
of nanotechnology. We discuss how nano-enabled technologies can efficiently process surface and groundwater for drinking. In
recent years, there has been significant advancement in nanotechnology in virtually every domain of science [2, 3]. So optimists
