Institute for Sanitary Engineering, Water Quality and Solid Waste ...

Chair of Sanitary Engineering and Water Recycling
Subterranean Arsenic Removal: From Experiment
to Delivery
Together with the Indian applicant organisation Ramakrishna
Vivekananda Mission – Institute of Advanced
studies (RKVM-IAS) the Institute for Sanitary Engineering,
Water Quality and Solid Waste Management
(ISWA) of the University of Stuttgart is implementing
the project “Subterranean Arsenic Removal: From Experiment
to Delivery”. The objective of this project is
to reduce in an affordable and sustainable manner the
health consequences of arsenic contaminated water
in rural communities of West Bengal, India by in-situ
treatment of groundwater. Within the project six insitu
treatment plants shall be established. The in-situ
treatment plants shall be manufactured and distributed/serviced
by local entrepreneurs. Further on they
shall be managed by self-sustained community groups
with the support of classroom and hands-on training.
Development of strategies for water circuit closure
for selected industries with split flow concept
Most industries used to treat or pre-treat the cumulative
waste waters of a factory, targeting in some cases
for a partial recycling. Some factories collect waste
waters according to their origin and treat these waste
waters independently. Nonetheless, often waste waters
are thereby blended from individual sources, differing
greatly in quantity and quality.
These blend waste waters are often difficult to be purified,
since the waste water constituents may vary
greatly. The treatment steps needed for a purification
of such waste waters will become complex and demanding,
mastering all eventualities. Thus, a recycling
of waste waters is not considered for economical reasons.
Paper industry
Main focus was given to the application of membrane
processes, mainly ultrafiltration and nanofiltration.
Ultrafiltration is much less costly than nanofiltration,
but only with nanofiltration and reverse osmosis solute
salts can be removed. Therewith, an effective sink is
created for the removal of salts, accumulating in the
circuits otherwise. Thus, with nanofiltration or reverse
osmosis applied, water circuits can be concentrated or
even closed, without deteriorating product quality.
Research is conducted both with waste waters from
paper mills producing white paper and mills producing
brown paper.
Fig.:
Pump room with tanks for oxygenation and degasification
Financing institution:
World Bank under Development Marketplace 2006
Project partner:
1. Queen’s University Belfast - School of Chemical
Engineering and Queen‘s University Environmental
Science and Technology Research Centre
(Questor Centre), Großbritannien
2. University of Stuttgart, Germany
3. Ramakrishna Vivekananda Mission – Institute of
Advanced studies (RKVM-IAS)
Contact:
Prof. Dr.-Ing. U. Rott
Dipl.-Ing. Ralf Minke, AOR
Dipl.-Ing. Manuel Krauß
The corresponding water circuits differ significantly in
respect to organic and inorganic waste water constituents.
The COD-levels in the water circuits for instance
are usually more than 10 times higher in mills producing
brown paper as they are in mills producing white
paper. The same applies to the concentration of soluble
salts, expressed in terms of conductivity, with a
factor of at least 5.
Besides the research on finding suitable membranes
and membrane combinations, focus is also given on
where to apply membrane processes. Biologically treated
water is usually easier to treat with membranes,
yet resulting in large amounts of concentrates to be
disposed. A membrane step close to the production,
i.e. the direct filtration of waste waters from the water
circuits, can result in a more cost-effective configuration
of subsequent biological treatment steps for the
resulting concentrates, since smaller streams with higher
concentration levels can be applied to for example
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