1. science
2. ecology
3. pollution

Wastewater Treatment and
Management Solutions
Cost and Energy Savings
Process Performance
Sludge Management
Process Control
Wastewater Treatment and
Management Solutions
Solutions in wastewater
management
Today, handling of environmental issues
by companies and municipalities, is not
just a matter of compliance. The situation
is much more complex. Issues like
economic and environmental sustainability
have gained increasing attention with
the public in general, and customers and
shareholders in particular.
Handling environmental issues should be
part of the general asset management of
companies and public utilities.
Within the wastewater treatment sector
there are several key areas that must be
considered when dealing with the multidisciplinary exercise of environmental
asset management:
DHI
DHI is an independent consulting and research
organisation with a global network of offices.
DHI offers a wide range of services and products,
including consulting, laboratory and physical
model testing, software and IT products and field
investigations. DHI has a staff of about 700 in 20
offices worldwide.
Consulting services are available across a wide
range of engineering and environmental issues
within ports and offshore technology, coastal and
river engineering, water resources, urban water,
water in industries and other areas related to the
water environment.
We provide consulting services to contractors and
consulting companies, industries, government
agencies and authorities, and as specialist
subconsultants in multidisciplinary teams. DHI
participates, at all stages, in projects ranging from
prefeasibility to operation and management.
Photos:
pp2, 3: Scanpix
Backcover: Lynetten, Copenhagen
All other photos: DHI
• Balanced extensions and technological
upgrading
• Management of industrial point source
pollution
• Cost and energy savings
• Capacity evaluation and process
performance
• Sludge management
• Collection and management of data on
WWTP operation
• Benchmarking
• Communicating environmental strategy
to local community and customers/
shareholders.
New methods for consulting, construction
and operation have emerged in recent
years, all focusing on closer cooperation
between the client and supplier. Such
partnering often includes a common
incentive, such as shared cost savings.
DHI delivers services and solutions for
environmental asset management in the
area of wastewater treatment, with focus
on close cooperation with our clients.
Cost and energy savings
All over the world, energy savings are in
focus. Savings allow other investments
while the cost of operation can remain
stable or even be reduced in the long
term. This is an important benchmark for
the management.
Management of industrial point
source pollution
Identification of pollution sources,
assessment of their impacts and
description of the potential for reduction
of the emissions are essential elements
in a water pollution control programme.
DHI offers a wide range of services, tools
and technologies for pollution prevention,
reduction and control:
• Strategies for identification of pollution
sources
• Regulation strategies for industrial
pollution sources
• Development of limit values for
discharges of xenobiotics and heavy
metals
• Planning and preparation of awareness
campaigns on water savings and reuse
• Pollution source tracking in urban
wastewater networks
• Fate of pollutants in sewer systems and
wastewater treatment plants
• Preparation of discharge permits for
complex industries
• Data handling, storage and presentation
using DHI’s software tool INDUSTRY
An energy audit will typically identify a
10-25% reduction in power consumption.
Changes with a payback time of less
than three years should be implemented
immediately. DHI will visit your plant and
measure power consumption for aeration,
blowers, pumps and ventilation. DHI also
provides one-day training courses in
energy savings for staff. DIMS online
energy and process control system can
be installed to maintain and identify new
energy savings.
Optimisation and new equipment
installations are often necessary to realise
the savings. DHI will test control
adjustments using a simulation program
prior to demonstrate and verify the
expected savings.
Better process performance
Requirements for the effluent quality are
increasing. Thus, a good understanding
and a detailed control of the wastewater
treatment processes are essential. At the
same time, operating costs should be kept
as low as possible.
With the aim of optimising the process
performance in terms of effluent quality
and operation costs, DHI services include:
• Troubleshooting
• Process control based on online sensors
• Systems for monitoring and assessment
of operational data
• Mathematical process modelling
Treatment plant extensions
For most WWTPs, a time comes when
upgrading is necessary, either to increase
the capacity or to introduce more
advanced wastewater treatment –
typically nutrient removal. DHI’s research
laboratory and years of experience will
help you build an efficient new plant.
DHI prepares feasibility studies including:
• Load assessments and forecasts
• Preparation of upgrading concepts
• Preparation of design guidelines
Sludge management
All wastewater treatment activities
generate sludge.The related treatment
and disposal costs are high - often
20-40% of the total operational budget.
Restrictions on final disposal are
increasing and call for a holistic solution.
DHI can prepare integrated sludge
handling plans including recommendations
for:
• Sludge dry solids minimisation
measures
• Recommendations for best sludge
dewatering technology
• Solutions for final disposal with a high
degree of supply safety
Technology tools
INDUSTRY is an IT tool for planners,
administrators and managers in water
companies, industrial estates and
municipal administrations. It gives a fast
and detailed geographic overview of point
sources and their specific loads to a sewer
catchment area. INDUSTRY is highly
valued for analysing loads to WWTPs and
effects of changes in catchments.
DIMS is an IT system collecting,
presenting and processing data from
many sources. It is an excellent tool,
which combines data and information
for increasing efficiency. At the same
time DIMS is a data management system
and an intelligent system for optimising
operation through SCADA systems.
Benefits are: lower costs, increased
capacity and a first-rate documentation of
operation. Energy and chemical savings
using DIMS are high. Together with a
possible increase of capacity, cheaper
operation gives a short pay back time.
WEST is a flexible, open and powerful
modelling system for wastewater
treatment plants. It can be used to
simulate almost any process and
configuration of modern WWTPs. Once
configured it can forecast and explain
performance and test operational design
strategies. It is used for troubleshooting,
scenario testing and cost estimation. It
is valuable for analysing operation and
design and is an important decision
support tool for operators.
Aars WWTP, Denmark
The objectives of the project were to
increase the capacity by at least 20%,
to reduce electricity consumption and to
minimise sludge production.
Marselisborg WWTP, Aarhus,
Denmark
Modelling was used to evaluate the
effects of internal carbon dosing on
denitrification.
DIMS was used to introduce a new cost
effective state of operation with four
basic strategies and a rain operation.
The Municipality of Aarhus obtained :
The following targets were reached:
• Capacity was increased by 25%
• Energy consumption (kWh) was
reduced by 25%
• Considerable savings on effluent tax
were achieved
• Sludge production was reduced
The investment was 80% lower than an
ordinary extension with more tanks.
Perstorp - a chemical industrial
complex in Sweden
Perstorp has several production units
within the complex. INDUSTRY was used
for managing monitoring data to highlight
and potentially solve several issues and
problems, including:
• Identification of heavy metal sources
• Establishing the contribution to total
load from individual units
• Discussions on priority and potential
for reductions
• Documentation for payment from
individual units
• Identification of potential for reuse
of clean water between the units
• Reduced nitrogen discharge from
the WWTP and thus reduced
environmental tax payment
• Pay back time of less than two years
for the carbon source project
• Justification of future investments in
water infrastructure
DHI OFFICES
Australia
DHI Water and Environment Pty Ltd
Tel: +61 2 9213 5700
australia@dhigroup.com • www.dhigroup.com
Canada
DHI Water & Environment
Tel: +1 519 650 4545
dhi-ca@dhigroup.com • www.dhigroup.com
China
DHI China
Tel: +86 21 6417 8810
lqm@dhigroup.com • www.dhigroup.com
Czech Republic
DHI a.s.
Tel: +420 267 227 111
office@dhi.cz • www.dhi.cz
Denmark
GRAS
Geographic Resource Analysis & Science A/S
Tel: +45 3532 2578
gras@ku.dk • www.gras.ku.dk
France
DHI
Tel: +33 2 4048 4040
dhi@dhi.fr • www.dhi.fr
Germany
DHI Wasser & Umwelt GmbH
Tel: +49 (0)4242 16380
dhi@dhi-umwelt.de • www.dhi-umwelt.de
India
DHI (India) Water & Environment Pvt Ltd
Tel: +91 11 2627 2275
ajay@dhi.co.in • www.dhigroup.com
Italy
Intecno-DHI
Tel: +39 011 56 24 649
Intecno-dhi@intecno-dhi.it • www.intecno-dhi.it
New Zealand
DHI Water and Environment Ltd
Tel: +64 9 912 9638
nz@dhiwae.com • www.dhiwae.com
Norway
DHI Water & Environment AS
Tel: +47 73 54 03 64
dhi@dhi.no • www.dhi.no
Poland
DHI Polska Ltd
Tel: +48 22 635 9332
dhipolska@dhigroup.com • www.dhigroup.com
Singapore
DHI Water and Environment (S) Pte Ltd
Tel: +65 6677 6330
dhi@dhi.com.sg • www.dhi.com.sg
Slovak Republic
DHI Slovakia s.r.o.
Tel: +421 2 4444 2760
office@dhi.sk • www.dhi.sk
Spain / Portugal
DHI España
Tel: +34 91 323 5020
dhi@dhi-es.com • www.dhi-es.com
Sweden
DHI Water & Environment AB
Tel: +46 31 80 87 90
dhi@dhi.se • www.dhi.se
United Arab Emirates
DHI Gulf
Tel: +971 4 360 2873
dhigulf@dhigroup.com • www.dhigroup.com
USA
DHI Water & Environment
Tel: +1 503 827 5900
dhi-or@dhi.us • www.dhi.us
Besides, DHI has project and sales offices
in Brazil, Japan, Thailand, Vietnam and
the United Kingdom.
Head Office
Agern Alle 5
DK-2970 Hørsholm
Denmark
Tel: +45 4516 9200
Fax +45 4516 9292
dhi@dhigroup.com
www.dhigroup.com
Aarhus Office
Science Park
Gustav Wiedsvej 10
DK-8000 Aarhus
Denmark
Tel: +45 8620 5100
Fax +45 8619 7511
dhi@dhigroup.com
www.dhigroup.com
Design: Ole Søndergaard • Printed by Nofo print • September 2007 • Photos: Scanpix • DHI
Bulgaria
DHI Bulgaria Ltd
Tel: +359 2 9454 078
v.bojkov@dhi.cz • www.dhi.cz
Malaysia
DHI Water & Environment (M) S/B
Tel: +60 88 260 780
dhikk@tm.net.my • www.dhi.com.my