the arsenic removal depends on the mechanisms of filtration, adsorption of arsenicbearing compounds and electric repulsion (Brandhuber and Amy 1998). The
removal rate of arsenic through this process is affected by shape, size and chemical
characteristics of contaminant species. Several membranes have been developed so
far for the removal of arsenic, which can be broadly classified into two categories:
high-pressure membrane (75–250 psi) and low-pressure membrane (10–30 psi).
Low-pressure membrane includes microfiltration (MF) and ultrafiltration (UF),
whereas high-pressure membrane includes nanofiltration (NF) and reverse
osmosis (RO).
2.5
Adoption of Technology at Rural Scale
In order to fulfil the requirement of arsenic-free drinking water for densely populated
countries such as India and Bangladesh, adoption of the technology at rural scale in a
convenient, economic and effective manner is a challenging task among the scientific communities. Several conventional technologies with modifications have been
reported to be accomplished in rural and remote areas to provide safe drinking water
(Fan et al. 2017; Sarkar and Blaney 2008). These technologies have been generally
classified as household treatment systems or community-based treatment systems. A
brief description of these technologies is presented below:
Aeration, boiling of water, sand filters, ceramic filters and oxidation using solar
light are among the typical methods of household treatment systems, where
contaminated water is treated from a single source and utilized for livestock’s
purposes such as cooking and drinking (Crabbe et al. 2017; Ahsan 2010). Whereas
in community-based treatment systems, many households invest money as a society
and make a single treatment unit. The advanced and costly methods for the treatment
of arsenic-contaminated groundwater are not affordable to most of the populations in
the world (Khettab and Chabbi-Chemrouk 2017; Singh 2017; Shahraki 2017).
Therefore, the focus of this research also describes the development of arsenic
remediation materials by utilizing industry waste as precursor material, which
might present a sustainable approach to upgrade the existing arsenic removal units
by providing indigenously generated nanoadsorbents.
2.5.1 Domestic or Household Treatment Systems
This type of technology was developed to provide arsenic-free water to the poor
people. Many developing countries are unable to afford centralized treatment
methods for arsenic remediation; therefore, different types of economic treatments
have been developed. Among these, the bucket treatment units (BTU), sono-filters
and bio-sand filter are quite common.
Bucket treatment unit is based on the arsenic removal processes, such as coagulation, co-precipitation and adsorption. It consists of two buckets placed one above
another. From the top, the arsenic-contaminated water is poured along with the
2 Nanotechnology-Based Treatment Systems for Arsenic Sequestration in. . .
41
removal rate of arsenic through this process is affected by shape, size and chemical
characteristics of contaminant species. Several membranes have been developed so
far for the removal of arsenic, which can be broadly classified into two categories:
high-pressure membrane (75–250 psi) and low-pressure membrane (10–30 psi).
Low-pressure membrane includes microfiltration (MF) and ultrafiltration (UF),
whereas high-pressure membrane includes nanofiltration (NF) and reverse
osmosis (RO).
2.5
Adoption of Technology at Rural Scale
In order to fulfil the requirement of arsenic-free drinking water for densely populated
countries such as India and Bangladesh, adoption of the technology at rural scale in a
convenient, economic and effective manner is a challenging task among the scientific communities. Several conventional technologies with modifications have been
reported to be accomplished in rural and remote areas to provide safe drinking water
(Fan et al. 2017; Sarkar and Blaney 2008). These technologies have been generally
classified as household treatment systems or community-based treatment systems. A
brief description of these technologies is presented below:
Aeration, boiling of water, sand filters, ceramic filters and oxidation using solar
light are among the typical methods of household treatment systems, where
contaminated water is treated from a single source and utilized for livestock’s
purposes such as cooking and drinking (Crabbe et al. 2017; Ahsan 2010). Whereas
in community-based treatment systems, many households invest money as a society
and make a single treatment unit. The advanced and costly methods for the treatment
of arsenic-contaminated groundwater are not affordable to most of the populations in
the world (Khettab and Chabbi-Chemrouk 2017; Singh 2017; Shahraki 2017).
Therefore, the focus of this research also describes the development of arsenic
remediation materials by utilizing industry waste as precursor material, which
might present a sustainable approach to upgrade the existing arsenic removal units
by providing indigenously generated nanoadsorbents.
2.5.1 Domestic or Household Treatment Systems
This type of technology was developed to provide arsenic-free water to the poor
people. Many developing countries are unable to afford centralized treatment
methods for arsenic remediation; therefore, different types of economic treatments
have been developed. Among these, the bucket treatment units (BTU), sono-filters
and bio-sand filter are quite common.
Bucket treatment unit is based on the arsenic removal processes, such as coagulation, co-precipitation and adsorption. It consists of two buckets placed one above
another. From the top, the arsenic-contaminated water is poured along with the
2 Nanotechnology-Based Treatment Systems for Arsenic Sequestration in. . .
41