TECHNICAL GUIDELINES (WATER MANAGEMENT CONCEPT) FOR PAPER MAKERS IN EUROPEAN REGIONS WITH DIFFICULT BOUNDARY CONDITIONS ON HOW TO OPERATE MILLS WITH MINIMUM WATER USE pdf

D
ELIVERABLE
D16:
TECHNICAL GUIDELINES (WATER MANAGEMENT
CONCEPT) FOR PAPER MAKERS IN EUROPEAN
REGIONS WITH DIFFICULT BOUNDARY CONDITIONS
ON HOW TO OPERATE MILLS WITH
MINIMUM WATER USE

RESPONSIBLE PARTNER: Centre Technique du Papier (CTP)
PROJECT CO-ORDINATOR: LUCENSE SCpA
P
ARTNERS
:
Papiertechnische Stiftung (PTS),
Centre Technique du Papier (CTP),
A.R.P.A.T.,
Serv.Eco Srl



Project funded by the European

Community under the “Energy,
Environment and Sustainable
Development” Programme (1998-2002)
D16 : WATER MANAGEMENT CONCEPT Page 2 of 23

Contents

1 Summary 3
2

Introduction 4

3 Systematic approach to Water Management 5
4 Minimising water usage 7
4.1

Cooling water network 7

4.2 Preparation and dilution of chemicals 7
4.3 Paper machine showers 7
4.4

Sealing waters 7

5 Optimum Water circuit Layout 8
5.1 Strict separation of water loops together with counter-current flows 8
5.2

Broke system management 8

5.3 Optimal water arrangement, water clarification and recycling of process
water for different purposes. 8
5.4

Adequate storage capacity 9

5.5 De-inking plant: generation of clarified water 9
6 Appropriate effluent treatment 11
6.1

Installation of an equalization basin and primary treatment of waste water 11

6.2 Secondary treatment 11
6.3 Anaerobic treatment as first stage of biological waste water treatment 12
6.4

Chemical precipitation of waste water from paper mills 13

7 Integration of advanced water treatment as an option to further reduce
process water loading 14
7.1

Introduction 14

7.2 Choice of technology 14
7.3 Elimination of organic compound 15
7.4

Elimination of inorganic compounds 15

8 Conclusions 17
9 Literature 18
9.1

Overview 18

9.2

Scientific background and investigations 18







D16 : WATER MANAGEMENT CONCEPT Page 3 of 23


1 SUMMARY
One important outcome of the EU-funded Project PAPERBREF
1
is the water management
concept about how to operate mills with minimum water use in European regions with
difficult boundary conditions. This concept is based upon studies performed in 30 paper
mills in the region of Tuscany, Italy, in 2002 and 2003. The paper grades produced in
these mills are packaging paper and tissue made of virgin fibre or recovered fibre. All
conclusions given are based on the results of these studies.
It is the aim of this study to describe all methods that have been successfully applied in
paper mills operating in typical European regions with difficult boundary conditions with

regard to water use. All methods mentioned are therefore adapted to these specific
conditions. Their implementation is a success factor that ensures compliance with local
and European standards.
The most important fields for achieving optimum water management are:
•
a structured approach towards water management in general
• minimised and improved fresh water use
• optimum water circuit layout
•
appropriate effluent treatment
• integration of advanced water treatment as an option to reduce process water
loading further
The latter should only be adopted if all other methods have been implemented and the
process water loadings are still too high. In any case, the most challenging part of
achieving improved water management is to counteract the build-up of detrimental
substances within the process and in the effluent.
The solution chosen is always an individual combination of the options described in this
document. The list of publications given is intended to enable the reader to obtain
additional information concerning improved water management in paper mills.


1

Water consumption reduction through application of the BREF for pulp and paper industry in
example paper mills
-
Feasibility, measures and local implications. Funded by the European
Commission within the 5
th
Framework program

D16 : WATER MANAGEMENT CONCEPT Page 4 of 23


2 INTRODUCTION
Knowledge acquired according to the PAPERBREF project concerning packaging paper
machine from recovered paper and tissue paper machines from virgin or recovered fibres
helps us define technical guidelines on a water management concept. This concept is
based on the BREF DOCUMENT and analysed through PAPERBREF project
experiments to minimise water usage.
Water reduction methods in paper and board machines are a complex issue and depend
greatly on the degree of closure desired. A balance between the advantages and the
drawbacks associated with the closing-up of water systems should be established. The
acceptable level of closure will depend on the paper grade produced, raw materials used
and water and pulp circuit management.

D16 : WATER MANAGEMENT CONCEPT Page 5 of 23


3 SYSTEMATIC APPROACH TO WATER MANAGEMENT
The enhanced recycling of process water in paper and board machines causes an
increase in the concentration of colloidal and dissolved organic and inorganic constituents
in these streams. Depending on the characteristics of the pulp in-feed and the used
chemicals in paper-making, the closed-up water systems can have an adverse effect on
the operation of the machine, the quality of end-product and even the production costs
due to the increased use of chemicals.
In the different actions listed below, it is very important to estimate the impact on the
evolution of physico-chemical quality of the process water. The build-up of organic and
inorganic materials can be balanced to a certain degree by the use of specific chemicals
in replacement of or in complement to the actual chemicals.

Before any investigation to operate with minimum negative environmental impact, paper
mills must have a complete overview of their process
. The methodology applied in the
Paper BREF project provides a detailed global view of the use of fresh water and of the
water circuit arrangement. A flow diagram of the in-mill stock and water systems must be
made to have an overview of the organisation of pulp and water circuits. Decrease in fresh
water consumption should involve modification in the physico-chemical quality of process
water, and analyses at reference points in the water system must be performed to
measure the initial load situation. All major fresh water consumers are identified and
measured.
Comprehensive information and the knowledge of experts will enable
1. an estimation of the fresh water saving potential. The detailed analysis of the fresh
water use will determine the fresh water “losses”, i.e. the non-polluted raw water
that goes to the effluent treatment plant without being re-used.
2. the system to be reorganised to improve water use in the paper-making process
and water quality around the paper machine to be improved.
The modification needed to operate with minimum fresh water consumption concerns the
re-use of non-polluted fresh water, water circuit management and the recycling of fresh
water or the substitution of fresh water by process water.
As a rule of thumb, the first methods to apply are those that have no effect on the organic
and inorganic loading of the process water. These methods concern:
1. The cooling water network with the re-use of this non-polluted water (in terms of
organic and inorganic load) as raw water for other process applications.
2. The decrease in sealing water flow.
3. All other fresh water losses identified by a detailed and specific analysis of the fresh
water used by the paper machine.
To minimise fresh water use and its drawbacks, a combination of the above list is
required:
1. Adequate storage capacity and efficient broke system management is of
prime importance with regard to the stability of the process water system.

2.
Efficient save-alls
that produce clarified water with a low suspended solid content
are essential to use process water instead of fresh water for applications such as
paper machine showers.
3. Backward re-use process water in the systems, counter current to the fibre flow
should also be applied.

D16 : WATER MANAGEMENT CONCEPT Page 6 of 23


For integrated pulp and paper mills and in particular recovered paper based mills, the
strict separation of water loops together with counter-current flows is of major
importance to restrict the organic load of process water around the paper machine.
The measure adopted to minimise water consumption should be applied
step by step
.
The following chapter describes the BAT mentioned above. They are classified in 4
groups: BAT concerning water management, BAT concerning the minimising of fresh
water consumption, BAT concerning Waste Water management and Advanced
Technology that could be applied in extreme cases where the water system closure must
be important.

D16 : WATER MANAGEMENT CONCEPT Page 7 of 23


4 MINIMISING WATER USAGE
4.1 Cooling water network
Fresh water used for cooling can reach 6 m3/t. Recycling this water in the fresh water
network to the paper machine presents real advantages due to the higher temperature.

There are no disadvantages because the only modification in the physico-chemical quality
of the water leaving the cooling circuit is an increase of temperature.
The cooling water network should be fed by the fresh water system and recycled to the
raw water tank of the paper machine.
If necessary, the cooling water system can be partially closed; in this case, a cooling
tower for re-use is then required.
4.2 Preparation and dilution of chemicals
The water quality used for the preparation of chemicals should be free from ionic
substances because pollutant introduced in this step will greatly alter adjuvant quality and
efficiency. The preparation of chemicals should be made with clean fresh water. Some
chemicals need dilution just before sending them to pulp flow. The contact between the
water of dilution and the chemicals before their contact with the pulp is very short. It is
then possible to use clarified water instead of fresh water for this application.
4.3 Paper machine showers
Clear or super-clear white water from the save-all is increasingly used in wet end wire
showers. The use of clarified water to feed wire showers requires adequate showers and
nozzles: shower cleaning equipment, with an internal brush or other purging equipment is
also necessary. To avoid plugging of the nozzle due to dysfunction of the save-all, water
distribution to such showers should go through a protective in-fine strainer, preferably of
the slotted type and equipped with an automatic purge. The opening size of this filter
should not exceed 1/6th of the spray nozzle diameter. To avoid plugging the nozzle, the
particle size is more important than the consistency.
The use of clarified water to feed felt showers needs a stronger filtration step and a
specific study must be carried out to ensure that the use of process water will not affect
the felt plugging.
4.4 Sealing waters
Sealing water used for circulating pumps can represent a high use of fresh water. Pump
constructors propose interesting alternatives with mechanical seals or dynamic water
tightness.
Vacuum pumps also need large quantities of sealing water. A recycling loop is

recommended for part of the vacuum pump sealing water with integrated cooling and
solids removal. Paper machine vacuum pumps that recycle used sealing water must have
strainers and, in the case of a high recycling rate, cooling systems in recycling lines to
maintain a high vacuum.
Some paper mills use clarified water as sealing water.
D16 : WATER MANAGEMENT CONCEPT Page 8 of 23


5 OPTIMUM WATER CIRCUIT LAYOUT
5.1 Strict separation of water loops together with counter-current flows
This measure concerns integrated pulp and paper mill and in particular the recovered
paper based mills. When recovered fibres are used, they represent the main polluting
source of soluble organic material. This soluble organic substances contaminates the
process water during pulping and is then contained within the process water. The principle
of strict separation of water loops means, that the pulp department, the bleaching
department and the paper mill department each have its own water circuit. The white
water from paper mill is then introduced into the loops of the pulp mill and thus the water
flow is counter-current to the product flow: the excess white water from paper machine
loop goes backwards to the previous department where water quality is less demanding,
and so on. The separation of the water loops is carried out with thickeners. The extra
thickener leads to an improved separation of the “dirty” stock preparation water and the
“clean” paper machine water and thus to significant reduction of organic substances that
enter the machine loop. The excess water from the whole system come from the first loop
i.e. the pulping department. Fresh water is mainly used in the paper machine loop. This
arrangement can reduced the organic load by a factor of between 2 and 4.
With this measure applied the fresh water consumption of the mill can be decreased and
at the same time minimizing drawback of a partial water closure. It can be applied to both
new and existing plants but needs high investments : thickeners and additional water
storage and piping.
5.2 Broke system management

Another important factor in closing the white water system regarding the wet-end stability
is to separate the broke and white water systems. Under normal operating conditions, the
white water from paper machine is relatively constant while the quality of broke varies.
Mixing broke with the white water system causes significant flow variations in the white
water system. Suggested broke system involved pumping from the couch pit and the dry-
end pulper to a common storage tank. From there, it passes through a cleaning device
and a deflaker to the blend chest with a controlled flow and a controlled consistency. In
line consistency control of the stock from the broke chest to blend chest is essential.
5.3 Optimal water arrangement, water clarification and recycling of process water
for different purposes.
The main principle of an optimal water arrangement is to backward re-use process water
in the systems, counter current to the fibre flow. The white water from the paper machine
is use for stock dilution before the fan pump (short circulation). The overflow is clarified in
saveall. One of the most important components of the paper machine white water system
is the saveall which separate liquids from solids. The saveall clarified water can be then
used in mill applications for adjusting stock consistency and in substitution of fresh water
application such as paper machine showers. The recovered stock is then re-use in pulp
circuit preferably in the machine chest. Clarification is achieve by sedimentation, flotation
or filtration. Each of these technologies has its own advantages and limitations.
Sedimentation tank are not any more available as saveall because of the length of time
involved for clarification which is not compatible with water circuit closure, risk of
anaerobic fermentation is too high. The most commonly used clarifiers today for white
water clarification are flotation saveall for tissue paper mill and for corrugating paper mill
and disk filter for all kind of production (and particularly for fine papers).

D16 : WATER MANAGEMENT CONCEPT Page 9 of 23


Flotation save-alls are effective in removing suspended and colloidal material but need the
help of coagulant/flocculant agents. At optimum conditions, flotation save-alls have a good

TSS removal efficiency. They are suitable for grades having fine and colloidal material in
stock but not for grades using fillers. The main disadvantages of flotation save-alls are:
•
difficulties in paper machine operation when recovered stock is added near the fan
pump
•
the sensitivity of flotation efficiency to process disturbances
• and operational costs
In a disk filter, liquid is forced through the filter layer by applying a vacuum. The build-up
of the fibres on the filter wire serves as the main filtration medium. The white water filtrate
is typically collected as two separate, cloudy and clear fractions. In some cases, even a
super clear fraction has been separated. The super clear filtrate from a disk filter could
have 10-20 mg/l and clear filtrate 20-50 mg/l solids, in comparison with well over 50 mg/l
of other save-alls. Thus, clear filtrate can be used in paper machines. The cloudy filtrate is
readily re-used in machine broke pulping and stock dilution. The main disadvantages of
disk filter are:
•
Space constraints: the disk filter must be installed several metres above the floor
• High maintenance costs
5.4 Adequate storage capacity
The most important item keeping the accident discharges to a minimum is the correct
sizing of the process water and broke chests. As a rule of thumb, a statistical study on the
broke pulp produced by each paper mill should allow the volume of the broke chest to be
adapted according to the rated production and significant water and solids discharge to
the sewer to be reduced. The white water storage capacity must match this broke storage
so that no fresh water is required during sheet breaks or when the broke is returned to the
machine. But the storage capacity of pulp, broke and process water should be optimised
so that it is not too large, because of microbial activity and not too small to avoid the need
to add fresh water for level control.
The white water tank level according to broke inventory, pulp inventory and production

plan must be checked to prevent spillage. The low and high tank levels must be optimised
and the pulp and process water storage tanks should contain an agitator.
In mills that change paper grades frequently, tank control is more difficult, because the
inventories are often kept low to minimise losses from clean-ups at grade changes. For
this reason, machine feed characteristics must be checked more carefully so that the
amount of broke stays low.
Control of accidental process water discharges is of primary importance in the paper
machine and can be applied in existing and new mills. However, problems are likely to
arise in existing old mills, which often do not have enough space to expand water or pulp
storage. Moreover, the level of automation in old or small machines should be restricted
because of the high costs involved.
5.5 De-inking plant: generation of clarified water
To remove upstream the dissolved and colloidal materials generated in the de-inking
plant, including anionic colloids that can induce secondary stickies on the paper machine
wire, the use of a DAF (Dissolved Air Flotation) to treat water in de-inking plants has
proved to be efficient. This practice increases efficiency of the ink removal and limits the
carry over of contaminant to the paper machine. The internal generation of clarified water
D16 : WATER MANAGEMENT CONCEPT Page 10 of 23


from de-inking process water is carried out in micro-flotation systems : the DAF. Unlike
water clarification in the paper mill, the solid material recovered from the DAF contains
contaminants and has to be disposed of as sludge.

D16 : WATER MANAGEMENT CONCEPT Page 11 of 23


6 APPROPRIATE EFFLUENT TREATMENT
Minimising water use can result in an increase in pollution load in terms of consistency,
and effluent then has to be treated before being sent to the recipient. The waste water

treatment plant consists of:
•
an equalisation basin to ensure that the WWTP is fed with a steady and
continuous flow
•
a primary treatment: physico-chemical treatment by flotation or settling to remove
suspended solids
•
a secondary treatment if necessary: biological treatment to remove organic
compounds
•
sometimes a tertiary treatment to remove specific pollutants.
6.1 Installation of an equalization basin and primary treatment of waste water
Equalization and spill collection is of prime importance in the pulp and paper industry:
effluents with large variations with regard to flow and content of pollutants are often
observed. Such variations disturb the functioning of the subsequent treatment processes.
An equalization basin before the waste water treatment is essential for the efficiency of
the primary and secondary treatments. The minimum retention time of the equalization
basin depends upon the paper-making process and can be determined by an analysis of
the reject flow variation.
Primary or mechanical treatment is carried out for the removal of solid particles, such as
fibres, bark particles and inorganic particles (fillers, lime particles, etc.). These particles
are usually referred to as (total) suspended solids (TSS or SS). This is the first type of
treatment to be applied at a pulp and paper mill, and it may be either the only treatment or
a pre-treatment ahead of, for instance, a biological process. The result of the primary
treatment depends on the effluent properties, but also on the degree of internal fibre
recovery in the pulp or paper mill. For suspended solids (TSS), the removal rate may be
within 60-95%. For solids that settle, removal will normally be higher, approximately 90-
95%. TSS values after the primary sedimentation may be in the range of 30-200 mg/l.
The effluent treatment plant produces sludge, which can be burned after dewatering,

providing in some cases net positive heat value, or can be used in agriculture.
6.2 Secondary treatment
Biological treatment is required if the COD or BOD load is too high with regard to local
legislation. The basic alternatives are aerobic and anaerobic biological systems. Different
techniques are available, but the choice of the appropriate technology depends on the
organic pollution load of the effluent to be treated.
The following table shows the technology that can be chosen according to the COD
concentration of the inlet effluent.
D16 : WATER MANAGEMENT CONCEPT Page 12 of 23



Tab. 1
Biological treatment technologies and recommended inflow COD loading



Biological treatment COD concentration
Percolating biofilter > 1000 mg/l
Activated sludge > 300 mg/l
Aerated lagoons > 300 mg/l
Trickling filter < 300 mg/l
Methanisation (anaerobic) > 2000 mg/l

6.3 Anaerobic treatment as first stage of biological waste water treatment
As a result of minimising fresh water usage, the COD load of process water increases and
thus the COD load in the effluent is too high to be treated in one stage.
Anaerobic treatment is adapted to effluents with high organic pollutant consistency and
has a BOD removal efficiency between 75% and 85%. Hence, anaerobic treated waste
water does not always comply with requirements for rejected pollution load. Effluents from

anaerobic treatment are often post-treated by an aerobic biological stage. With an
anaerobic-aerobic waste water treatment, very efficient pollution load reduction (95 – 97
% for COD ; 99 – 99,8 % for BOD) is obtained and biologically treated water can even be
recycled back into the water circuit.
Anaerobic treatment can be performed with different techniques:
• UASB reactor (Upflow Anaerobic Sludge Blanket),
•
Fixed-bed reactor,
• Fluidised-bed reactor.
Compared with aerobic waste water treatment much less biomass is produced during the
anaerobic degradation process. Significant reduction in excess sludge production results
from anaerobic treatment as the first stage of a biological treatment plant. In a combined
anaerobic/aerobic treatment plant, the biomass production is reduced by 80 %.
Biogas produced during anaerobic degradation ranges from 400 to 600 m
3
/t COD with 70
% in methane and 30 % in CO
2
. The energy resulting from the use of biogas is a power
plant producing 1 to 3 % of the total energy requirement of the mill.
Excess sludge can be returned to the paper production process as the input on the raw
material is less than 1 %. But recycling sludge in the process must be carefully examined
and cannot be applied in all the cases because of potential disturbances to the process.
D16 : WATER MANAGEMENT CONCEPT Page 13 of 23



6.4 Chemical precipitation of waste water from paper mills
In some case, environmental regulation is so restrictive that paper mills have to post-treat
effluent after the biological step. This BAT is an alternative or complementary technique to

aerobic biological treatment. Chemical precipitation involves the addition of chemicals to
facilitate the removal of dissolved material and suspended solids by sedimentation of
flotation. Chemicals used are aluminum salts, ferric salts, lime and poly-electrolytes.
Chemical precipitation reduces nutrients (phosphorus), suspended solids and some
organic (dissolved and colloidal) compounds.
Chemical precipitation as a secondary treatment of paper mill waste water is particularly
adapted to tissue mills from virgin fibres and avoided a biological plant. Reductions of
about 99 % for TSS, 80 % for COD are achieved. The soluble part of COD is only slightly
reduced (about 20 %) but for tissue mills from virgin fibres the COD polluting load is weak.
D16 : WATER MANAGEMENT CONCEPT Page 14 of 23


7 INTEGRATION OF ADVANCED WATER TREATMENT AS AN OPTION TO
FURTHER REDUCE PROCESS WATER LOADING
7.1 Introduction
Some paper mills have totally closed up the process circuits. The reasons are often linked
to an environmental constraint (lack of fresh water, town proximity, reject legislation too
strict). But for a paper mill, working with a totally closed water system is very difficult:
concentration near 40 g/l in COD is obtained with totally closed circuits. Drawbacks are
multiple: corrosion problems because of anaerobic conditions associated with sulphate
reduction bacteria and high temperature, increasing use of additives (biocides, slimicides,
anti-foaming and retention adjuvants), clogging of wire and felts, product quality problems,
scaling formation. One way to limit the drawbacks is to introduce kidney devices in the
circuit. With deconcentration processes, it would be possible to achieve a COD level and
a saltiness in the circuits equivalent to an open circuit with acceptable concentration levels
providing good characteristics to the paper products. But integration of required kidney
devices needs high investment, increased operating costs and can lead to an important
increase in reject and sludge.
7.2 Choice of technology
The treatment technology selected has to eliminate solids and COD, but also salts.

Concentrates and rejects should be treated in a separate step.
Different technologies are available to eliminate organic and inorganic compounds.
However, not all these technologies are able to eliminate at the same time organic
compounds and ions. A comparison between different treatment technologies is given in
the figure below.


Electro


dialyses

Electro


dialyses

Ultrafiltration

Ultrafiltration

Biological treatment

Biological treatment

Evaporatore

Evaporator

Ozonisation

Ozonisation

F

locculation

/

precipitation

F

locculation

/

precipitation

Nanofiltration

Nanofiltration

Reverse

osmosis

Reverse

osmosis

Solids

COD

Salts

Bacterial

elements


Colouring


Fig. 1
Treatment technologies available and respective elimination of contaminants (bubble size
correlates with efficiency)
D16 : WATER MANAGEMENT CONCEPT Page 15 of 23



7.3 Elimination of organic compound
The best available technology to eliminate organic compound is biological treatment that
turns COD relevant substances into easily disposable biological sludge. Two methods can
be considered: aerobic biological treatment or anaerobic biological treatment. The
commonly used and well-known biological treatment in the pulp and paper industry is
aerobic treatment with activated sludge treatment. But the other technology should be
considered.
Anaerobic treatments present a real advantage compared with aerobic processes

because of the typically high temperature of the process water. This temperature is
sometimes high enough to eliminate the need for preheating and excess biomass
formation can be kept at a low level in order to reintroduce these solids into paper
production and to eliminate the need for sludge dewatering and handling. This requires
smaller and less expensive installations than aerobic treatment with lower operating costs
and energy saving through the production of methane.
The basic idea to deconcentrate the organic pollution present in the circuits is to adapt
external treatments, normally used for ordinary paper mill waste water treatments, for in-
mill treatment. The main advantage is to eliminate only part of the COD load from a purge
of the white water to remove a given level of contaminant. This will be sufficient for the
paper-making process and will result in economically attractive waste water treatment
plants. Current practice in treating high strength wastewater from the purge circuits
involves first a physical treatment to remove recoverable fibres to be re-circulated and re-
used in paper production and then the purge flow is treated in the anaerobic system.
CTP has done a great deal of research on this concept and a pilot study at a paper mill
that produces corrugating medium from waste corrugated board in a closed circuit has
demonstrated that it is possible to insert an anaerobic reactor in the white water circuit to
deconcentrate the organic pollution. Data from this pilot study have been used to
determine the design of an industrial-scale installation at a paper mill.
7.4 Elimination of inorganic compounds
The two technologies that are technically acceptable to treat paper process water are:
1. tangential filtration with reverse osmosis
2. and evaporation

7.4.1 Tangential filtration
Membrane filtration is a unit separation procedure based on pressure differential across
the thickness of the membrane (transmembrane pressure). It is not a frontal filtration but
conventionally a cross-flow filtration, in which the membrane surface is continuously
swept, minimising membrane fouling.
Ultrafiltration has proved its efficiency in removing suspended solids but this technology is

not available for removing salt and COD. Nanofiltration can be used to remove COD and
bivalent ions such as sulphate and calcium but not monovalent ions such as chloride.
Only reverse osmosis is capable of removing salts with good separation efficiency. The
reverse osmosis and nanofiltration technology must be combined with ultrafiltration as
pre-treatment. The permeate could be used as raw water and the concentrate should be
dewatered and eliminated from the circuit.
D16 : WATER MANAGEMENT CONCEPT Page 16 of 23


Tangential filtration can be used in combination with a biological treatment: membrane
bioreactor. Over the last two years, trials on paper machine effluent, carried out at CTP,
have demonstrated several advantages of the combined technologies: higher stability of
global purification yield, higher volumetric loading elimination of the suspended solids in
effluent, lower biological sludge production.
At PTS, an EU research project on a combination of biological treatment and nanofiltration
is in progress.
7.4.2 Evaporation
Evaporation techniques are mainly used in pulp processing for waste liquid evaporation.
The removal efficiency of these techniques is effective for salts containing univalent and
bivalent ions and also for COD. The extreme cleanliness of the obtained condensate is
the great advantage of the technique. However, so far no evaporation plant exists for the
treatment of paper making process waters, mainly due to the high investment costs.
These techniques for in-mill treatment are promising for paper mill operation with a totally
closed water circuit. The condensate could be used as raw water and the concentrate
should be eliminated from the circuit.
At PTS, there was a research project from 1995 to 1997 on vacuum evaporation for the
treatment of circuit water.
D16 : WATER MANAGEMENT CONCEPT Page 17 of 23

8 CONCLUSIONS
Paper mills, located in regions with difficult boundary conditions, should be able to work
with minimum fresh water consumption by applying the combination of the guidelines
described below. It is important to note that the reduction in fresh water use involves
further modification in the process water management. Without specific study to optimise
the water circuit arrangement, the reduction in fresh water use can lead to major
disturbances in the operation of the paper machine.
Each paper and board machine has its own characteristics and the best solution to
minimising fresh water consumption will be specific to the machine. To operate with
minimum negative environmental impact, paper mills must have a complete overview of
the process. The environmental performance achieved through the application of
individual BAT depends on the specific situation of each paper mill. The methodology
applied in the PAPERBREF project provides a detailed global view of the water circuit
arrangement and allows the system to be re-organised to improve water use in the paper
making process and to improve water quality around the paper machine. Simulation tools,
specific to each paper mill, make it possible to find the best arrangement of process
circuits and to determine the optimum device to reach specific objectives.
Despite advanced technology, the complete water circuit remains very difficult to apply
and still requires years of research activity.
To obtain a precise view of their optimisation potential, paper mill managers can ask for
water management expert consultancy from the Helpdesk accessible via the
PAPERBREF Web site (o) .




D16 : WATER MANAGEMENT CONCEPT Page 18 of 23


9 LITERATURE

9.1 Overview
ZIPPEL F.: Water management in paper mills
Heidenheim, Germany: Dr. F. Zippel 2001
MÖBIUS C.H.: Abwasser der Papier- und Zellstoffindustrie (Wastewater of Pulp and Paper
Production)
German Version 3.02

N.N. (H.A.SIMONS, NLK CONSULTANTS, SANDWELL, PULP and PAPER RESEARCH
INSTITUTE OF CANADA): Water use reduction in the pulp and paper industry 1994
– a monograph
Vancouver: Canadian Pulp and Paper Association 1994
N.N.: Integrated Pollution Prevention and Control (IPPC), Reference Document on Best Available
Techniques in the Pulp and Paper Industry, July 2000
European commision, European IPPC Bureau (Ed.)
WILLIAMSON P.N., BROWNE T.C. (ED.): Energy cost reduction in the pulp and paper industry
Pointe Claire: Pulp and Paper Research Institute of Canada, 1999
9.2 Scientific background and investigations
APPLEYARD C. and J. LANDER: Establishing a strategy for effective water source management
and control in: Water use and reuse. Rugby: Institution of Chemical Engineers 1994,
23 – 38
AUHORN W. and J. MELZER: Untersuchung von Störsubstanzen in geschlossenen
Kreislaufsystemen. Wochenblatt für Papierfabrikation 107 (1979), Nr. 13, S. 493
BAUMGARTEN H.L. and U. WELCKER: Zur Technologie des Wassergebrauchs in Papierfabriken.
Das Papier 40 (1986) Nr. 10 A, 181 - 192
BERARD P.: Filling in the holes after closing up the loop
Pulp and Paper International 42:4, 45-51 (2000)
BERARD P.: Practical solutions to problems frequently associated with water closure
In: 27th EUCEPA Conference. Crossing the Millenium Frontier; Emerging Techn.
and Scientific Challenges. 11 14.10.1999. ATIP (Ed.); Paris: Association Technique
de l'Industrie Papetiere (ATIP) 1999, S. 153-162

BIENER R., MEIERS R., KUSSI J S. and H. LEIMKÜHLER: Systematische Reduktion des
Wasserverbrauchs und des Abwasseranfalls, 1999 GVC-Abwasser-Kongress
Verfahrenstechnik der Abwasser und Schlammbehandlung. Koblenz: Fuck 1999,
71-80
BOURGOGNE G., LAINE J.E: A review of the effects of reduced water consumption on the wet
end of the paper machine and the quality of paper
Paperi ja Puu 83, 3, 190-203 (2001)
BOYKO J., ANDERSON J., LOCKHART C.: Reduction of paper machine water consumption
Pulp & Paper Canada 100:7, p. 42-45 (1999)
BRECHT W. and F. ZIPPEL: Wege zur Verbesserung des Wasserhaushalts von Papierfabriken
Darmstadt: Eduard Roether Verlag 1963. 226 S.
BRUN J. and B. CARRE: Dissolved air flotation of process waters in deinking; 9th PTS/CTP
deinking symposium, Munich, 9-12 May 2000
DALPKE H L.: Warum Kreisläufe (in einer Papierfabrik)? Wochenblatt für Papierfabrikation 127
(1999) Nr. 3, 135 - 136
DEMEL I, KAPPEN J. and F. SCHMID: Reduzierung der spezifischen Abwassermenge in Altpapier
verarbeitenden Betrieben. Das Papier 50
(199
6
), Nr.
10A
,
V48
–
V54


D16 : WATER MANAGEMENT CONCEPT Page 19 of 23

DEMEL I. and J. KAPPEN: Verfahrenstechnik zur Optimierung von Wasserkreisläufen.
Wochenblatt für Papierfabrikation 127 (1999) Nr. 3, 141-145
DEMEL I.: Stand der Abwasserreinigung. in: Betrieb biologischer Abwasserreinigungsanlagen -
Der Weg zur prozessstabilen Anlage. München: (PTS) 2000, PTS-Manuskript PTS-
MS 2019, 1-1 – 1-14
DIEDRICH K., HAMM U. and J.H. KNELISSEN: Biologische Kreislaufwasserbehandlung in einer
Papierfabrik mit geschlossenem Wasserkreislauf. Das Papier 51 (1997) Nr. 6A,
V153 – V159
DIETZ W. and J. KAPPEN: Using process simulation as a tool to optimise water management in
paper mills
CTP Forum Recherche
Grenoble 19./20. Jan. 2000
EDELMANN K., KAIJALUOTO S. and M. KARLSSON: Towards effluent free paper mill
Das Papier, S. V138-V145 (1997) 6A
ERHARD K.: Stoffwäsche zur Kreislaufentlastung; in: Wassergebrauch in Papierfabriken; in:
Wassergebrauch in Papierfabriken. München: PTS Verlag 1995, 3. teils
überarbeitete Auflage 1995, 352 S., PTS-Manuskript PTS-MS 07/94/5, 16-1 – 16-30
GEISTBECK M.: Die Bedeutung des Kreislaufwassers für den Fabrikationsprozess. Wochenblatt
für Papierfabrikation 122 (1994) Nr. 11, 463 - 467
GELLER A. and W. LÜTTGEN: Folgeprobleme der Kreislaufeinengung und Maßnahmen zur
Abhilfe; Das Papier 35, V 151-V 159 (1981), Nr. 10 A
GELLER A.N.: Korrosion, Schleim- und Geruchsbildung bei der Verringerung des spezifischen
Abwasseranfalls in Papierfabriken. Wochenblatt für Papierfabrikation 112 (1984) Nr.
2, 49 - 58
GILBERT C.D., HSIEH J.S., XU Y., DENG Y.: Effects of white-water closure on the physical
properties of linerboard
Tappi Journal 83, Nr. 4, pp. 68-68 (2000)
HAMILTON R. and D. DOWSON: Pinch cleans up. The Chemical Engineer 49 (1995) Nr. 7, 1127-
1135
HAMM U.: Wasserkreisläufe von Verpackungspapierfabriken

Wochenblatt für Papierfabrikation Nr. 5, S. 303-306 (1999)
HAMM U., BOBEK B., DEMEL I. and W. DIETZ
Scheitert die Kreislaufschließung in Papierfabriken an zu hohen
Calciumbelastungen?
Vortrag gehalten auf der Zellcheming-Hauptversammlung 26 29.06.2000
Das Papier, T7-T13 (2001)
HAMM U., GÖTTSCHING L.
Abwasserfreie Papierherstellung - Welche Vorteile sind zu erwarten?
Allgemeine-Papier-Rundschau 50-51, S. 22-28 (2002)
HERSCHMILLER D.W. and C.R. HASTINGS: Elements of a Water Conservation Programm
In: Water Use Reduction in the Pulp and Paper Industry 1994. Vancouver: Paprican
1994 S.13-27
HÜSTER R.: Integrierte Schleimlimitierung Wochenblatt für Papierfabrikation 123 (1995), Nr. 6,
254 – 258
JOORE L., VERSTRAETEN E. and A. HOOIMEIJER: Competitive Dutch Paper and Board Industry
by Closed Water Systems beyond 2000. 1999 International Water Conference
„Towards Closed Water Systems in Papermaking“, Feb. 10
th
Papendal; Arnhem The
Netherlands, Delft: TNO 1999
JOORE L.P.A.A., COENEN E.L.J., VERSTRAETEN E.A.M. ET AL.
Links between process water qualities and product properties - an integral approach
D16 : WATER MANAGEMENT CONCEPT Page 20 of 23


to water management in papermaking
Paper Technology 41:4, 47-56 (2000)
KAPPEN J. and W. DIETZ: Bestandsaufnahme und Verbesserung von Wasserkreisläufen in
Papierfabriken mit integrierter Holzstofferzeugung. München: PTS, PTS-
Forschungsbericht PTS-FB 07/99,48 S.

KAPPEN J.: Kennwerte als Werkzeuge zur Minimierung des Wasserbedarfs bei der
Papiererzeugung – ein Beitrag zum prozessintegrierten Umweltschutz
Berichte aus Wassergüte und Abfallwirtschaft, TU München, Berichtsheft Nr. 166
München: Hieronymus Buchreproduktions GmbH 2001
KAPPEN J., DEMEL I. and H J. ÖLLER: Besondere Anforderungen an Wasserkreisläufe beim
Deinken.
Wochenblatt für Papierfabrikation 124

(199
6
), Nr. 20, 910 -
917


KAPPEN J., DEMEL I. and W. DIETZ: Simulationstechnik als Werkzeug zur Prozessoptimierung
bei der Papiererzeugung. IPW - Das Papier (2001) Nr. 2, 38 - 44
KAPPEN J., DEMEL I.: Increasing closure of water circuits in recycling mills
Revue ATIP Nr.3 (1998)
KAPPEN J.: Bestandsaufnahme und Verbesserung von Wasserkreisläufen in Papierfabriken mit
integrierter Altpapierstofferzeugung, München: PTS, PTS-Forschungsbericht PTS-
FB 03/96, 149 S.
KAPPEN J.: Optimierung von Wasserkreisläufen in der Praxis; in: Wasserkreisläufe in der
Papiererzeugung – Verfahrenstechnik und Mikrobiologie. München: (PTS) 2000;
PTS-Manuskript PTS-MS 2017, 1-1 – 1-14
KARLSSON M. R.: Making Paper Using Less Energy and Water; in: Environmental Conference,
Atlanta: TAPPI Press 1999, 101 – 107
KOTILA P.S. and T.E. ESTES: Closed Mill Systems and Implications for Process Water Reuse.
Progress in Paper Recycling (1994) Nr. 8, 42 - 46
LAUFMANN M. and W. HUMMEL: Neutrale holzhaltige Papierherstellung 1990. Wochenblatt für
Papierfabrikation 119 (1991), Nr. 8, 269 - 293

LINNHOFF B. et al.: A user guide on process integration for the efficient use of energy. The
institution of Chemical Engieneers, Rugby: 1982
MAECK K., DIETZ W.: Verringerung des Frischwasserbedarfs bei der Erzeugung holzfreier
Druckpapiere ohne Qualitäts- und Produktivitätsverlust
Abschlussbericht AiF 12810; www.ptspaper.de
MEDVECZ P. J.: Review of chemical composition, process implications, measurement techniques
and control strategies for interfering substances in the papermaking process; in
Papermakers Conference 1993. Book 2, S. 451 - 459. Atlanta: TAPPI-Press 1993
MELTON A.: Process simulation as a tool for closing water loops
Paper Technology 41, Nr. 7, 27-30 (2000)
MÖBIUS C.H. u. M. CORDES-TOLLE: Paradigmenwechsel in der Vermeidung von
Abwasseremissionen der Papierindustrie
Das Papier 6 A, V160 -V165 (1997)
MÖBIUS C.H.: Die Störstoffkonzentration als begrenzender Wert für die Verringerung der
spezifischen Frischwassermenge in Papierfabriken. Wochenblatt für
Papierfabrikation 112 (1984) Nr. 16, 559 - 562
MÖBIUS C.H.: Verfahrens- und Anlagentechnik bei der Verringerung der spezifischen
Abwassermenge. Wochenblatt für Papierfabrikation 112 (1984) Nr. 3, 75 - 82
NIVELON S., PICHON M. and A. PIOLLET: Deconcentration treatment for corrugating medium
papermaking circuits: Target zero reject
In:84th Annual Meeting. Book A. Conference 01.27 01.28.1998; Montreal; Quebec.
CPPA; Montreal(Ed.); Technical Section; Montreal: CPPA S. A123-126 (1998)
D16 : WATER MANAGEMENT CONCEPT Page 21 of 23


ÖLLER H J., WEINBERGER G. and I. DEMEL: Weitergehende CSB-Elimination und Entfärbung
durch Ozonbehandlung biologisch gereinigter Papierfabriksabwässer. Das Papier 51
(1997) Nr. 4, 177 – 182
PANCHAPAKESAN B.: Closed White Water System Designs; in: Papermakers Conference.
Atlanta: Tappi Proceedings 1993, 219 - 225

PAULY D.: Kidney-Technology – Auf dem Weg zu geschlossenen Wasserkreisläufen; in:
Wasserkreisläufe in der Papiererzeugung – Verfahrenstechnik und Mikrobiologie.
München: (PTS) 2000; PTS-Manuskript PTS-MS 2017, 5-1 – 5-19
PAULY D.: Novel process on thermophilic conditions opens up new opportunities of integrated
white water treatment in recycling mills – KIDNEY-technology concept.
In: water recycling and resource recovery in industry, IWA Publishing. Piet Lens,
Look Hulshoff Pol, Peter Wilderer and Takashi Asano (eds.)
Wageningen, The Netherlands, ISBN 1 84339 005 1, chapter 28, pp. 585-604
(2002)
REID B. and A. G. LOZIER: Retrospective of closed-cycle CTMP operations. 1996 TAPPI Minimum
Effluent Mills Symposiums, Atlanta: TAPPI Press 1996, 151-158
RUIZ J. and P.OTTENIO: Analyse et optimisation du fonctionnement des circuits papetiers", Revue
A.T.I.P., Vol.52,n°2, 1998
RYÖSÖ K, MANNER H.: Paper mill circulation water as a feed water of retention aids
Revue ATIP 54, Nr.1, 29-33 (2000)
SCHWARZ M. and J. VELINSKY: Überlegungen zur Wasserführung in Altpapier verarbeitenden
Papierfabriken. Wochenblatt für Papierfabrikation 122 (1994) Nr. 21, 825 - 832
SUHR M.: Geschlossene Wasserkreisläufe in der überwiegend altpapierverarbeitenden
Papierindustrie – Stand der Technik?
In: Seminar 21. Weitergehende Abwasserreinigung. UTECH Berlin 26./27.2.1996.
Berlin: Fortbildungszentrum Gesundheits- und Umweltschutz Berlin e.V. 1996, S.
294
TRAUGOTT W. and W. BERGER: Überlegungen zur Kreislaufwasserführung bei der Erzeugung
holzhaltig gestrichener Papiere. Wochenblatt für Papierfabrikation 117 (1989), Nr. 9,
365 - 369
WANG Y.P. and R. SMITH: Wastewater minimization. Chem. Eng. Sci. 49 (1994) Nr. 7, 981-1006
WISEMAN N., JOHANNESEN J.: Influence of water system closure on strength properties of
packaging papers; Revue ATIP 54 Nr.5/6, 135-139 (2000)
9.2.1 Field reports
BAUMGARTEN H.L, EWERT A.: Anforderungsprofile innerhalb der Wassersysteme einer

Feinpapierfabrik
Wochenblatt für Papierfabrikation Nr. 5, S. 308-310 (1999)
BÜLOW C., G. PINGEN G., HAMM U.: Schließung des Wasserkreislaufs einer Altpapier
verarbeitenden Papierfabrik unter besonderer Berücksichtigung der Calcium-
Problematik
ipw - Das Papier 1, 31-38 (2003)
BÜLOW C., PINGEN G., HAMM U.: Complete water system closure
Pulp and Paper International 45:8, 14-17 (2003)
CADDET project database: Examples of international applications of energy efficiency and
renewable energy technologies;
DALPKE H L., GISSLER-WEBER R., BREUER H., BÖTTCHER H., MINNE S.: Über die Lösung
der Probleme eines geschlossenen Prozesswasserkreislaufs in einer
altpapierverarbeitenden Papierfabrik.
Wochenblatt für Papierfabrikation 108, S. 797 – 805 (1981), Nr. 21
D16 : WATER MANAGEMENT CONCEPT Page 22 of 23


DIEDRICH K., HAMM U., KNELISSEN J. H.: Biologische Kreislaufwasserbehandlung in einer
Papierfabrik mit geschlossenem Wasserkreislauf
Das Papier 51, V153-V159 (1997), Nr.6A
GERBASI B., STUART P. R., ARSENAULT F. u. R. ZALOUM: Techno-economic assessment of
several closed cycle technology alternatives for an existing TMP-newsprint mill
Pulp & Paper Canada 94:12,123-128 (1993)
HABETS L.H.A., HOOIMEIJER A. and H.J.KNELISSEN: In-line biological process water treatment
for zero discharge operation at recycled fibre board mills
Pulp & Paper Canada 98, T504-T507 (1997), Nr. 12
HABETS L.H.A.; KNELISSEN H.J.; HOOIMEIJER A: Improved paper quality and runability by
biological process water recovery in closed water circuits of recycle mills
In: 1996 International Environmental Conference. Book 1.; Conference 05.05
05.08.1996; Orlando. TAPPI; Atlanta(Ed.); Atlanta: TAPPI Press 1996. S. 249 – 257

HOULE J.F., BROUSSEAU Y., PARIS J.: Reduction of fresh water consumption for process and
non-process uses in an integrated newsprint mill
Pulp and Paper Canada 100:3, T76-T79 (1999)
JANTUNEN E. A.: Effluent-free newsprint mill
In: International Environmental Symposium EU CE PA, Paris, 27 29.04.93
KLINKER R.: Hennepin Paper Company's zero effluent discharge program. TAPPI 1995
International Environmental Conference Proceedings, Atlanta: TAPPI Press 1995,
1127-1135
KÜNZEL U.: Untersuchungen im Wasserkreislauf einer Papierfabrik für mittelfeine Papiere
Wochenblatt für Papierfabrikation, 854-859 (1987), Nr. 19
NUORTILA-JOKINEN J., HEISKANEN P. and J. MATULA: Practical methods to reduce water
consumption in a printing paper mill
Wochenblatt für Papierfabrikation 21, S. 1392-1395 (1999)
RICKETTS J.D.: Considerations für the closed-cycle mill
Tappi Journal 77 No. 11, 43-49 (1994)
ROUSSEAU S., DOIRON B.: Zero process effluent discharge attained at St-Laurent Paperboard
Inc., Matane, Quebec
Pulp and Paper Canada 97:9, 57 - 60 (1996)
SCHAAREMAN M., VERSTRAETEN E., BLAAK R., HOOIMEIJER A. and I. CHESTER: Energy
and water pinch study at the parenco paper mill
Paper Technology 2, p.47-52 (2000)
SCHMIDT T.: Kreislaufschließung - Maßnahmen and Folgen
Wochenblatt für Papierfabrikation, Nr. 4, S. 227-230 (1999)
SCHMIDT T.: Kreisslaufschliessung – Massnahmen und Folgen. Wochenblatt für Papierfabrikation
127 (1999) Nr. 4, 227 - 230
THOMPSON C.B., GARNER A.: Paper machine corrosion and progressive closure of the white
water system
In: 1996 Papermakers Conference. Conference 03.24 03.27.199; Philadelphia.
TAPPI; Atlanta(Ed.); Atlanta: TAPPI Press 1996. S. 545 - 552
TRAUGOTT W. and W. BERGER: Überlegungen zur Kreislaufwasserführung bei der Erzeugung

holzhaltig gestrichener Papiere
Wochenblatt für Papierfabrikation 117, 365 - 369 (1989), Nr. 9
WEARING J.T., BARBE M.C. and M.D. OUCHI: The Effect of White-Water Contamination on
Newsprint Properties, Journal of Pulp and Paper Science, 11(1985) Nr. 4, J113 –
J121
D16 : WATER MANAGEMENT CONCEPT Page 23 of 23


WEARING J.T., HUANG S., PIGOTT A., OUCHI M.D. and A.WONG: New white-water
management strategies for integrated newsprint mills. Pulp & Paper Canada 86
(1985), Nr. 5, T139 – T145
WEBB L.: Closing up the loop without closing down the mill
In: Pulp & Paper International, S. 43-46 (1997), Nr. 6