Study of removal of arsenic by algae SP. and water hyacinth (eichhornia crassipes) from arsenic enriched wastewater
Student name: Ms Rachita Arora
Guide: Dr Arun Kansal
Year of completion: 2012
Host Organisation: TERI University
Abstract: Various methods for treatment of heavy metal contaminated water exist and are successfully able to
remove them, up to the drinking water standards (< 0.01 mg/L, WHO standard). However, little
concern has been given to the treatment of the sludge/brine left after the treatment for disposal,
which contains these heavy metals in extremely high concentrations. In comparison to the
conventional methods of treating heavy metals from this brine/sludge, bioremediation techniques are
more beneficial, both environmentally and economically. Here, a comparative study on the use of
aquatic plant Water hyacinth (Eichhornia crassipes) and algae species for remediation of heavy
metal (Arsenic) is performed. Water hyacinth and algae species were grown in artificial ponds in
outdoor conditions, having waste water spiked with arsenic. They were tested for their ability to
thrive in and remove arsenic from the water. The study aims at testing the feasibility of using Water
hyacinth and algae species in outdoor artificial ponds for treating arsenic enriched waste waters; to
the extent of being disposed safely on land. The permissible limit prescribed by the CPCB for Arsenic
concentration in water which is to be disposed on land is 0.2 mg/L. The study revealed that Water
hyacinth could not survive in high concentrations of arsenic present in the waste water (> 6mg/L).
However, algal species was able to survive better than water hyacinth. The algal species could also
reduce arsenic concentration to some extent. However, for algae to be used as a full-fledged
remediation technique, more studies need to be done on the same.
Key words: Water hyacinth, Algae species, Arsenic, remediation, artificial ponds.
