Subsurface Iron and Arsenic Removal

156 Pages·2011·5.48 MB·English

Doris van Halem
Subsurface Iron and
Arsenic Removal
for drinking water treatment in Bangladesh
Subsurface Iron and Arsenic Removal
for drinking water treatment in Bangladesh
Proefschrift
ter verkrijging van de graad van doctor
aan de Technische Universiteit Delft,
op gezag van de Rector Magnificus prof. ir. K.C.A.M. Luyben,
voorzitter van het College van Promoties
in het openbaar te verdedigen op maandag 3 oktober 2011 om 15:00 uur
door
Doris VAN HALEM
civiel ingenieur
geboren te Eindhoven
Dit proefschrift is goedgekeurd door de promotoren:
Prof. ir. J.C. van Dijk
Prof. dr. G.L. Amy
Samenstelling promotiecommissie:
Rector Magnificus voorzitter
Prof. ir. J.C. van Dijk Technische Universiteit Delft, promotor
Prof. dr. G.L. Amy UNESCO-IHE/Technische Universiteit Delft, promotor
Dr. ir. J.Q.J.C. Verberk Technische Universiteit Delft
Prof. dr. K.M.U. Ahmed University of Dhaka
Prof. dr. ing- U. Rott Technische Universität Stuttgart
Prof. dr. ir. H.H.G. Savenije Technische Universiteit Delft
Prof. dr. P.J. Stuyfzand Vrije Universiteit Amsterdam
Prof. dr. ir. W.G.J. van der Meer Technische Universiteit Delft, reservelid
ISBN: 978-90-8957-022-2
Published by Water Management Academic Press
Copyright © 2011 by D. van Halem
All rights reserved. No part of the material protected by the copyright may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written
permission from the copywright owner.
Cover design: S. Willems (www. sjorswillems.nl)
Printed in the Netherlands
Acknowledgements
Acknowledgements
The desire to make a difference has been the driving in the last year(s), either retired or working in Jeddah,
force to start my PhD research, but along the road I it was essential to have a daily supervisor. Jasper, thank
have also increasingly enjoyed the scientific aspects of you for all the guidance and laughs, you are a valuable
it. This dissertation could not have been written without colleague.
the people around me, so thank you all for making my My time in Bangladesh was a success thanks
PhD period anything but lonely. to the great support of Rick Johnston (Unicef), his
First of all I thank my two promotors, Prof. Hans know-how and generosity helped me get started in this
van Dijk and Prof. Gary Amy, who have given me the beautiful country. At the Department of Public Health
opportunity to take this new research direction. Hans, Engineering I want to thank Ihtishamul Huq, Sudhir
your enthusiasm and confidence have encouraged me Ghosh and Shah Alam for tackling loads of political and
to approach this research in my own way. I enjoyed practical hinders, and for assisting in the monitoring
working with you, especially because you know how to program. Dhonnobad.
transfer your knowledge (and gezond boerenverstand) The field research in the Netherlands would not
without dominating the discussion. Gary, thank you have been possible without the support and hospitality
for sharing your broad expertise with me, and I am of Oasen Drinking Water Company and Vitens
glad that I also got to know you as a kind and caring Drinking Water Supply at WTPs Lekkerkerk, De Put
person. With two promotors operating from a distance and Loosdrecht. I am also thankful for the funding of
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Subsurface iron and arsenic removal for drinking water treatment in Bangladesh
AgentschapNL in their InnoWator program. it is the interaction with the world that makes you
During the past four years I was lucky to reconsider your route.
supervise many (international) students, whose results Naturally it is impossible to enjoy four years of
have contributed to several of my published papers. I research without the occasional distraction of friends
especially want to thank Samuele, David and Harmen and family. I want to thank you all for asking me about
who have battled the O and challenged me with my research, and maybe even more for not asking.
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surprising questions. In the final months of my PhD period it was great
At TU Delft, I want to thank my colleagues to have the support of my two paranimphs, Geerte and
for accompanying me on this PhD journey, which Harmen, who share my enthusiasm for research and
took us from coffee breaks, past tropical beaches and helped me with the last hurdles.
inspiring discussions (on water bugs and hydrophobia), I realize that it is because of my loving parents
to running the 10km. With special thanks to Mieke, that I approach life with an open and positive mind.
Weren, David, Bas, Luuk, Arne, Sheng, Anke, Petra, Pap en mam, thanks for supporting me, your believe in
Tonny, Martine and Stefan. I wish Sandra, Moshiur, me gives me wings.
Zahid and Debasish all the best in pursuing their PhD Most of all I want to thank Wieger, for always
within the newly started NWO WOTRO project on keeping me close whether I am in Delft or on the other
Subsurface Arsenic Removal. I also want to thank my side of the world. I do not know why we are so lucky,
colleagues at UNESCO-IHE, who have made the start of but life is amazing with you. And Ferre, you are my
my PhD more enjoyable. Addionally, I want to mention little explorer, curious and brave, the best example a
the TU Delft and UNESCO-IHE laboratory staffs who scientist can get.
have provided great assistance from analysis with GF-
AAS to designing (oxygen-free) column installations.
Apart from my direct colleagues, it has been
very inspiring to discuss my findings with so many Een rivier dankt haar naam
(international) scientists at conferences and meetings, aan de oevers, want het water
and during peer-review processes. A PhD path is not stroomt anoniem voorbij.
something you walk by yourself in solitude, because T. van Lieshout,1987
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Table of contents
Table of contents
Acknowledgements iii
1 Introduction 1
2 Subsurface iron removal in the Netherlands 23
3 Small-scale subsurface iron and arsenic removal in Bangladesh 37
4 Simulation of adsorptive-catalytic oxidation in sand columns 51
5 Cation exchange during subsurface iron removal 67
6 Characterization of accumulated deposits 81
7 Catalysis by accumulated deposits 99
8 Influence of groundwater composition 111
9 Concluding remarks 125
Summary 135
Samenvatting 139
List of publications 145
Biography 148
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Subsurface iron and arsenic removal for drinking water treatment in Bangladesh
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1
Introduction
Parts of this chapter are based on:
van Halem et al. (2009) Drinking Water Engineering and Science 2: 29-34
van Halem et al. (2010) Desalination 248: 241-248
Subsurface iron and arsenic removal for drinking water treatment in Bangladesh
An introduction to the arsenic
hazard related to drinking water (Johnston et al., 2001).
1
problem Only contamination by pathogenic microorganisms has
a bigger impact worldwide. Arsenic contamination of
groundwater (Box 1.1) has been found to occur due to
A worldwide problem (Smedley and Kinniburgh, 2002):
The World Health Organization estimated in 2001 that • geothermally- influenced groundwater;
about 130 million people worldwide are exposed to • mineral dissolution (e.g., pyrite oxidation);
arsenic concentrations above 50 μg.L-1 (WHO, 2001). • desorption in the oxidising environment, and;
Affected countries include Bangladesh (>30 million • reductive desorption and dissolution.
exposed people), India (40 million), China (1.5 million)
and the United States (2.5 million). The problem of Reductive dissolution of young arsenic-bearing
arsenic-contaminated source waters is, however, not sediments is the cause of the large-scale arsenic
confined to these countries, as illustrated in Figure contamination of the strongly reducing aquifers in the
1.1. According to the United Nations Synthesis report, Bengal Delta. Also in China the reducing conditions
arsenic poisoning is the second most important health in the subsurface are the cause of arsenic mobilization.
Figure 1.1 Arsenic-affected countries of the world (Smedley and Kinniburgh, 2002; Appleyard et al., 2006;
Petrusevski et al., 2007; Smedley et al., 2007; Gunduz et al., 2009; Jovanovic et al., 2011)
2
1 Introduction
Box 1.1 Arsenic speciation, including an Eh-pH diagram for aqueous arsenic species in the system As-O-HO at 25°C and 1 bar total
2 2
pressure (Smedley and Kinniburgh, 2002) 1
Arsenic is stable in four oxidation states (+5, +3, 0, -3)
under redox conditions occurring in aquatic systems
(Furguson and Gavis, 1972). However, in the aqueous
environment, arsenic occurs mainly as two species; trivalent
arsenic, arsenite or As(III) and pentavalent arsenic, arsenate
or As(V). Under oxidizing and aerated conditions, the
predominant form of arsenic in water is As(V) (as HAsO2-
4
or HAsO- around neutral pH), whereas if reducing
2 4
conditions prevail, As(III) (around neutral pH as HAsO) is
3 3
the predominant arsenic compound (WHO, 2001). As(III)
is thermodynamically unstable in oxic environments and
oxidizes to As(V); however studies have shown that this
reaction proceeds slowly when oxygen is the only oxidant
(AWWARF, 2000; Kim et al., 2000; Stollenwerk, 2003).
Therefore both As species can be found in natural systems.
The speciation of arsenic is controlled by pH within a
particular oxidation state, while the redox potential controls
the distribution of arsenic species between the two oxidation
states (Masscheleyn et al., 1999; Bose and Sharma, 2002).
Concentrations up to 1,800 μg.L-1 have been measured in Chile and Argentina (Smedley and Kinniburgh, 2002).
Inner Mongolia, a northern province of China (Smedley Also mining activities have been found to contribute to
et al., 2003). In Vietnam and Cambodia, arsenic arsenic contamination in Latin American groundwater
concentrations were also observed to be high (up to 1,340 (Smedley and Kinniburgh, 2002). Mining activities may
μg.L-1) due to reductive dissolution of young sediments cause the oxidation of arsenic-bearing sulphide minerals
(Buschmann et al., 2007; Buschmann et al., 2008). resulting in the release of arsenic into groundwater.
Arsenic mobilization caused by mineral dissolution Smedley and Kinniburgh (2002) listed cases of arsenic
has been found in active volcanic areas of Italy (Aiuppa contamination caused by mining activities in Canada,
et al., 2003) and inactive volcanic regions in Mexico Germany, Ghana, Greece, Mexico, South Africa,
(Armienta and Segovia, 2008). Volcanism in the Andes Thailand, UK, USA and Zimbabwe. In the past years,
has lead to arsenic contamination of groundwater in more and more countries have found their waters to
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