Mitigating Global Arsenic Crisis Through Innovations

112 Pages·2013·20.98 MB·English

Mitigating Global Arsenic Crisis Through
Innovations: Past Progress and Future Challenges
Arup K. SenGupta, P.C. Rossin Professor

Department of Civil and Environmental Engineering
Department of Chemical Engineering
Lehigh University, Bethlehem, PA 18015
USA
February, 1995

LAOS
SOME EARLY SYMPTOMS AND MANIFESTATIONS
Maximum Contaminant Level (MCL) of Arsenic in
drinking Water in USA Has Been Reduced from 50 µg/L
to 10 µg/L (Effective January 2006)
Cases of arsenicosis
in Cambodia
A Contaminated Well in
Cambodia
Vent/Overflow
O )
Air (
2
Splash Plate
Water Droplets

m Oxidation of Fe2+ to HFO
m
2+ +
5 4Fe +O +10H O ⇒ 4Fe(OH) (s)+ 8H
2 2 2 3
9
HFO
As(III) and As(V) Sorption onto HFO &
Sorbent
As(V) Binding:
Adsorbent
Monodentate Bidentate
+
Bed MOH

m MOH + O– O 2 – O
m 2 O
As As
–
0
5 HO OH
0 φ 350 mm + OH
1 O
MOH
2
As(III) Binding:
• •
FeOH HO − As = O
Support gravel media
Backwash
Treated
(A) Water (B)

November 18, 2006