Make an Energy Champion out of Your Wastewater Treatment Plant
2. Lower load to biological treatment
Chemical pre-treatment significantly
reduces the BOD load, and in some
Optimize the energy balance
in your WWTP with targeted
chemical treatment
cases nitrogen load, going to secondary
treatment. This leads to savings in aeration
energy and gives a more stable operation.
1. More energy-rich sludge
With chemical pre-treatment, more sludge
with the very highest energy value is
produced, going directly to the digester.
Energy and the environment go hand in hand
More biogas results in a major positive
Clearly the most important job of your waste water treatment plant
impact on the overall plant energy balance.
Primary
settings
is to purify the water before release to the recipient. However, the
potential for bio-energy production is also rapidly becoming a key
consideration for WWTP operators. What is today primarily considered to be a waste water treatment plant could tomorrow very
possibly also be seen as an important source of bio-fuel.
8. Sludge dewatering
Our expertise helps you do it
Our products ensure that the driest pos-
water
Our know-how in waste water chemistry, applied wisely to key
sible sludge is produced,. High dryness
means energy savings on transportation
sludge
operations in your plant, can significantly increase the net output of
energy, giving both financial and environmental benefits.
as well as higher energy value in
biogas
the sludge.
The figure at the right shows a fairly typical plant, with highlights on
Our patented KemiCond process can
the areas that have the greatest potential for energy improvement.
achieve dry solids content over 40%, for a
The biggest energy gain can be achieved by pre-precipitation of SS
big reduction in drying and freight energy.
and BOD in the primary settling tank. In this manner, more energyrich sludge goes straight to the digester.
This also leads to energy savings in activated secondary treatment.
In general, it takes about 1-1.3 kWh of aeration energy to degrade
1 kg of BOD. By removing more of the BOD with pre-precipitation
7. Anti-scaling
in primary settling, big energy savings in aeration can be achieved.
Our anti-scaling know-how can help maintain the most
efficient energy transfer in heat exchangers and the
lowest possible pumping energy, for further gain.
3. Smaller volumes in activated sludge
Smaller volumes of activated sludge are
needed, giving savings in aeration cost due
to reduced endogenous respiration.
4. Flocculation of biosludge
Activated
sludge
Secondary
settings
Whether the biosludge has a problem with
Improved thickening, which reduces sludge volumes, also has
filaments or not, we can make the biosludge
high potential for energy gain because it effectively increases the
more compact, saving pumping energy costs.
capacity of the digester. This extra capacity can be utilized either by
longer retention times or by using the free capacity for alternative
feed streams such as available organic waste. Either way, the result
is higher biogas output, giving energy and environmental benefits
Get a double return: Use less, produce more!
With smart use of chemicals, you can get the double effect of
producing more energy-rich biogas, while at the same time
5. Thickening
requiring less energy to run your plant. The result: Better economic
Correct treatment gives thicker sludge which can
efficiency of your WWTP. Chemical pretreatment does not affect
reduce the volume by up to 50%.
de-nitrification if done correctly. Of course, chemical treatments
• This effectively increases the digester capacity
cost money as well, but the net energy and financial balance is
by the same amount, allowing much higher
very positive. An additional advantage is that a plant operation is
retention time.
often more stable and smooth running after Kemira’s experts have
• Alternatively, it gives you the option to use other
analyzed it for optimum performance.
feed sources such as organic waste streams.
Big energy and big money
Our calculations show that for a waste water treatment plant
with flow of 100,000 m3/day, the net positive energy balance can
increase by 32,000 kWh/day or over 11 million kWh annually. While
these figures will vary from case to case, it gives you an idea of the
potential gain.
6. Improved biogas production
With iron coagulants present in the digester hydrogen sulfide,
Interested? Contact your local Kemira sales representative today
which is toxic to methane bacteria and also corrosive, is
to get started with an evaluation of your plant for the energy
precipitated and removed. The result: more biogas.
benefits you can get.
Kemira makes this information available as an accommodation to its customers and it is intended to be solely a guide in customer’s evaluation of the products. You must test our products, to determine if they are suitable for your intended
uses and applications, as well as from the health, safety and environmental standpoint. You must also instruct your employees, agents, contractors, customers or any third party which may be exposed to the products about all applicable
precautions. All information and technical assistance is given without warranty or guarantee and is subject to change without notice. You assume full liability and responsibility for compliance with all information and precautions, and with
all laws, statutes, ordinances and regulations of any governmental authority applicable to the processing, transportation, delivery, unloading, discharge, storage, handling, sale and use of each product. Nothing herein shall be construed as a
recommendation to use any product in conflict with patents covering any material or its use.
Kemira in brief
Kemira is a global two billion euro chemicals company that is focused on serving
customers in water-intensive industries. The company offers water quality and
Kemira Oyj
P.O. Box 330
FI-00101 Helsinki, Finland
quantity management that improves customers’ energy, water, and raw material
Tel. +358 10 8611
efficiency. Kemira’s goal is to be a leading water chemistry company.
www.kemira.com