1. An overview on arsenic contamination in groundwater: health hazard
and recent advances in its removal techniques
Deepak Kumar Tripathi1, Ashutosh Kumar Mishra2
1National Institute of Technology Karnataka, Surathkal.
2National Environmental Engineering Research Institute, Nagpur
Objectives
To investigate different potential areas contaminated with geogenic Arsenic in ground water
Identification of the health hazard related to Arsenic contamination
Comparative study on Arsenic removal techniques.
Treatment Facility
Efficiency
Cost
Advantages
Disadvantages
Ion exchange
Iron Coated Sand and resins
Less efficient because of competition of other ions
Operation cost higher
Readily available and fast processing
High O&M cost. Interference of sulfate and TDS.
Membrane Process
Candel filtration
very effective at removing arsenic from groundwater
Costly process
Can be used on household level
Filter media disposal
Nanofiltration
High removal efficiency
O&M cost is high
High removal efficiency and fast removal process -
Reverse osmosis
Efficient removal
Efficient and fast process
Required water supply to install. And pretreatment is also required.
Adsorption Techniques
Activated Alumina
Efficient
Cost effective
& readily available
Simple to operate
Efficiency strongly depends on pH, Salinity, and competing ions in water.
Permanganate (KMnO4)
and FeCl3
High efficiency as compared to other oxidation materials
Treatment cost is low
Can be implemented at household level
Clays and
mineral-containing rocks
Effective but Slow Process
Not very effective because of presence of Ca++ , Mg++ and other naturally occurring ions
Recent Advances
Microbial oxidation followed by Precipitation
Very high removal efficiency
Less costly
Oxidation of Iron is much faster than chemical oxidation method
Operational and maintenance problems of bioreactors.
Solar oxidation and removal of As
45 -78% removal efficiency
No power requirement
Co-precipitation, coagulation and flocculation
High efficiency
Can be implemented onsite
Bucket treatment Unit
Removal efficiency is higher
and efficient
No power requirement and can be implemented in rural areas
Durability is less
Electro-Chemical Arsenic Remediation (ECAR) Technology
Highly effective
Efficient and Less costly
Lesser Waste generation
Arsenic pollution in groundwater and its severe effects have been recognized as a major health concern globally.
Arsenic is one of WHO’s 10 chemicals of major public health concern.
In India, the major state affected are West Bengal, Jharkhand, Bihar, Uttar Pradesh.
Health Hazard
Technologies for Arsenic Removal
Conclusion
Along with the individual approach of above discussed techniques ,other potential approaches like Phytoremediation  and microbial assisted removal of arsenic should be popularize and researched further for effective mitigation to the arsenic problem
References
Muhammad Luqman, Muhammad Mohsin Javed, Abdullah Yasar, Jamil Ahmad and Amin-ul-Haq Khan. An overview of sustainable techniques used for arsenic removal from drinking water in rural areas of the Indo-Pak subcontinent. Soil Environ. 32(2): 87-95, 2013.
Arsenic Removal Technologies: A Review. Accessed on March 11,
K. B. Vu, M. D. Kaminski and L. Nuñez, Review of Arsenic Removal Technologies for Contaminated Groundwaters, 23-25, 2013.