treatment of pulp and paper mill wastewater—a review
TRANSCRIPT
www.elsevier.com/locate/scitotenv
Science of the Total Environment 333 (2004) 37–58
Treatment of pulp and paper mill wastewater—a review
D. Pokhrel, T. Viraraghavan*
Department of Environmental and System Engineering, Faculty of Engineering, University of Regina,
3737 Wascana Parkway, Regina, SK, Canada S4S 0A2
Received 2 July 2003; received in revised form 29 January 2004; accepted 7 May 2004
Abstract
Pulp and paper mills generate varieties of pollutants depending upon the type of the pulping process. This paper is the state
of the art review of treatability of the pulp and paper mill wastewater and performance of available treatment processes. A
comparison of all treatment processes is presented. Combinations of anaerobic and aerobic treatment processes are found to be
efficient in the removal of soluble biodegradable organic pollutants. Color can be removed effectively by fungal treatment,
coagulation, chemical oxidation, and ozonation. Chlorinated phenolic compounds and adsorable organic halides (AOX) can be
efficiently reduced by adsorption, ozonation and membrane filtration techniques.
D 2004 Elsevier B.V. All rights reserved.
Keywords: Pulp; Pulp and paper; Wastewater; Treatment
1. Introduction
The rapid increase in population and the increased
demand for industrial establishments to meet human
requirements have created problems such as overex-
ploitation of available resources, leading to pollution
of the land, air and water environments. The pulp and
paper industry is one of the most important industries
of the North American economy and ranks as the fifth
largest in the U.S. economy (Nemerow and Dasgupta,
1991). In Canada, the pulp and paper industry
accounts for a major portion of the country’s economy
in terms of value of production and total wages paid
(Sinclair, 1990). The wood pulping and production of
the paper products generate a considerable amount of
0048-9697/$ - see front matter D 2004 Elsevier B.V. All rights reserved.
doi:10.1016/j.scitotenv.2004.05.017
* Corresponding author. Tel.: +1-306-5854094; fax: +1-306-
5854855.
E-mail address: [email protected] (T. Viraraghavan).
pollutants characterized by biochemical oxygen de-
mand (BOD), chemical oxygen demand (COD), sus-
pended solids (SS), toxicity, and color when untreated
or poorly treated effluents are discharged to receiving
waters.
The high water usage, between 20,000 and 60,000
gallons per ton of product, (Nemerow and Dasgupta,
1991) results in large amounts of wastewater genera-
tion. The pulp and paper industry is considered as the
third largest polluter in the United States (US). It has
been estimated that the pulp and paper industry is
responsible for 50% of all wastes dumped into Cana-
da’s waters (Sinclair, 1990). The effluents from the
industry cause slime growth, thermal impacts, scum
formation, color problems, and loss of aesthetic beauty
in the environment. They also increase the amount of
toxic substances in the water, causing death to the
zooplankton and fish, as well as profoundly affecting
the terrestrial ecosystem.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5838
The growing public awareness of the fate of these
pollutants and stringent regulations established by
the various governmental authorities such as provin-
cial and federal agencies are forcing the industry to
treat effluents to the required compliance level before
discharging them in to the environment. Many stud-
ies have been conducted so far on this sector regard-
ing the impacts as well as the control of the
pollutants. Berube and Kahmark (2001), Kahmark
and Unwin (1996, 1998, 1999), and Srinivasan and
Unwin (1995) have reviewed pollution control as-
pects of the pulp and paper industry. However, all
these reviews have focused on the state of the art in
integrated pollution management and lack a compara-
tive evaluation of various treatment processes partic-
ular to the water pollution control. This review,
therefore, would examine the pollution control sys-
tems and compare the performance of the effluent
treatment measures in use.
2. Process description
Pulping is the initial stage of the paper making
industry and provides the processed material. It is the
largest source of the pollution in the whole process of
papermaking. High amounts of wastewater are gene-
rated at different stages of this process.
2.1. Mechanical pulping
The yield of the pulp by this process is as high as
90–95% (Smook, 1992) but the quality of the pulp is
of low grade, highly colored, and contains short
fibers.
2.2. Chemical pulping
The wood chips are cooked with appropriate
chemicals in an aqueous solution at an elevated
temperature and pressure to break chips into a fibrous
mass. The yield of the pulp by this process is about
40–50% of the original wood material (Smook,
1992). The chemical pulping is carried out in two
media: alkaline and acidic.
(a) Kraft process: The woodchips are cooked in a
solution of sodium hydroxide (NaOH) and
sodium sulfide (NaS2). This process is widely
used.
(b) Sulfite process: The wood chips are cooked in a
mixture of sulfurous acid (H2SO3) and bisulfide
ions (HSO3�) to dissolve lignin.
2.3. Chemo-mechanical pulping (CMP)
The raw material is first treated chemically and
then subjected to drastic mechanical treatment to
separate the fibers. The efficiency of pulp obtained
ranges from 85–90% and the strength of the pulp is
relatively better than the pulp from the mechanical
pulping alone.
2.4. Thermo-mechanical pulping (TMP)
This process involves steaming the raw materials
under pressure for a short period, prior to and during
refining. The thermo-mechanical process is further
modified using chemicals during the steaming stage,
and the process is called chemi-thermomechanical
pulping (CTMP).
2.5. Papermaking
The paper making operation consists of two parts;
one is stock preparation by treating the pulp to the
required degree of fitness and the other is paper
making where the treated pulp is passed through
continuous moulds/wires to form sheets.
3. Sources of pollution
Each pulping process utilizes large amounts of
water, which reappear in the form of an effluent.
The most significant sources of pollution among
various process stages are wood preparation, pulping,
pulp washing, screening, washing, bleaching, and
paper machine and coating operations. Among the
processes, pulping generates a high-strength waste-
water especially by chemical pulping. This wastewa-
ter contains wood debris and soluble wood materials.
Pulp bleaching generates most toxic substances as it
utilizes chlorine for brightening the pulp. Pulp fibers
can be prepared from a vast majority of plants in
nature such as woods, straws and grasses, bamboos,
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 39
or canes and reeds. Wood is the most abundant source
of papermaking fiber. Wood consists of various com-
pounds (lignin, carbohydrate, and extractives) which
are hard to biodegrade, and these derivatives are
washed away from the fibers during the washing,
dewatering, and screening processes. Depending upon
the type of the pulping process, various toxic chem-
icals such as resin acids, unsaturated fatty acids,
diterpene alcohols, juvaniones, chlorinated resin
acids, and others are generated in the pulp and paper
Fig. 1. Pollutants from various sources of pulp
making process. The pollutants at various stages of
the pulping and paper making process are presented in
Fig. 1.
It is clear that an individual pulping stage gene-
rates different quantities, qualities and types of
pollutants. The wastewater pollution load from indi-
vidual pulping and papermaking process is given in
Table 1.
The amount of pollutants produced by an indivi-
dual mill is an important indicator to evaluate the
ing and papermaking (US EPA, 1995).
Table 1
Typical wastewater generation and pollution load from pulp and
paper industry (Rintala and Puhakka, 1994)
Process Wastewater
(m3/adt pulp
or paper)
SS
(kg/adt
pulp)
COD
(kg/adt
pulp)
Wet debarking 5–25 nr 5–20
Groundwood pulping 10–15 nr 15–32
TMP -unbleached 10–30 10–40 40–60
TMP-bleached 10–30 10–40 50–120
CTMP-unbleached 10–15 20–50 70–120
CTMP-bleached 10–15 20–50 100–180
NSSC 20–80 3–10 30–120
Ca-sulfite (unbleached) 80–100 20–50 nr
Ca-sulfite (bleached) 150–180 20–60 120–180
Mg-sulfite (unbleached) 40–60 10–40 60–120
Kraft-unbleached 40–60 10–20 40–60
Kraft-bleached 60–90 10–40 100–140
Paper making 10–50 nr nr
Agrobased small
paper mill
200–250 50–100 1000–1100
nr—not reported; adt—air dry ton; NSSC—neutral sulfite semi-
chemicals.
Table 3
Comparison of actual emissions from pulp mills (TAPPI, 1990)
Country Parameters
SS
(kg/adt)
BOD
(kg/adt)
COD
(kg/adt)
AOX
(kg/adt)
N
(kg/adt)
P
(kg/adt)
Bleach kraft
USA 5 5 – 2.2 – –
Sweden 3.8 12 68 2 0.23 0.09
Bleached sulfite
Sweden 6.8 17.8 145 1.8 0.3 0.10
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5840
performance of the system as well as a crosscheck
whether the mills have followed the guidelines. Table
2 provides performance data of selected processes and
mills.
The environmental guidelines on discharge vary
with countries. The emission data from USA and
Table 2
Typical pollution load per ton of production (kg/ton)
Process Pollutants
SS BOD COD Color Reference
Deinking – 11 54 – Vlyssides and
Economides
(1997)
Wood yard 3.75 1 – 2 Springer (2000)
Pulping 13.5 5 – 1.5 Springer (2000)
Bleaching 6 15.5 – 40 Springer (2000)
Papermaking 30.8 10.8 – 1.5 Springer (2000)
Riocell
(Brazil)
0.4–0.5 0.2–0.3 5–5.5 19–20a Foelkel (1989)
Large mill
(India)
31.2 13 82.4 – Srivastava et al.
(1990)
Small mill
(India)
140.3 152.26 639.4 – Srivastava et al.
(1990)
Sweden 0.7 0.2 7.6 – Carlson et al.
(2000)
a Pt–Co (kg/ton).
Sweden for selected process are presented in Table
3. The pollutant load discharge guidelines for the pulp
and paper industry of some countries are presented in
Table 4.
4. Wastewater characteristics
The characteristics of the wastewater generated
from various processes of the pulp and paper industry
depend upon the type of process, type of the wood
materials, process technology applied, management
practices, internal recirculation of the effluent for
recovery, and the amount of water to be used in the
particular process. As an example, Mohamed et al.
(1989) reported that the load of chlorinated phenols
and acids in the wastewaters of hardwood kraft mill
was three to eight times lower than it was in the soft
wood kraft mill. The general characteristics of the
Table 4
Discharge limits (monthly, semiannual, or annual verges) for
bleached kraft pulp
Country Parameters
SS
(kg/adt)
BOD
(kg/adt)
COD
(kg/adt)
AOX
(kg/adt)
Reference
Canada 9.5–14.5 5.5–30 – 1.4–1.5 TAPPI, 1990
Finland 5–15 6.8–34 90 1.4 TAPPI, 1990
Norway 5 – 90 6 TAPPI, 1990
Sweden 0.3–5.8 7.5–17 39–107 1.5–2 TAPPI, 1990
Belgium 7–14.4 2.3–5.4 22–63 1.5 TAPPI, 1990
France 6.5–10 3.3–30 48–95 – TAPPI, 1990
USA 3.86
(8.47)
2.41
(4.52)
Reserved 0.272
(0.476)
US EPA, 2000
The U.S. EPA values are monthly average values for new bleached
kraft mill. The values in the ( ) are daily maximum allowable.
Table 5
Typical characteristics of wastewater (mg/l) at different processes (Bajpai, 2000)
Process Parameters
pH SS BOD5 COD Carbohydrate Acetic
acid
Methanol N P S
TMP (1) – 383 2800 7210 2700 235 25 12 2.3 72
TMP (2) 4.2 810 2800 5600 1230 – – – – –
CTMP – 500 3000–4000 6000–9000 1000 1500 – – 167
Kraft bleaching 10.1 37–74 128–184 1124–1738 – 0 40–76 – – –
Kraft foul (1) 8.0 16 568 1202 – – 421 – – 5.9
Kraft foul (2) 10.2 0 10,700 16,000 – – – 306 1 91
Kraft foul (3) 9.5–10.5 0 5500–8500 10,000–13,000 – – 7500–8500 350–600 0.02–1.55 120–375
Sulfite
condensate (1)
2.5 – 2000–4000 4000–8000 – – 250 – – 800–850
Sulfite
condensate (2)
2.8–5.9 – 3700–5110 9800–27,100 – – – – – 840–1270
NSSC Pulping:
Spent liquor – 253 13,300 39,800 6210 3200 90 55 10 868
Chip wash – 6095 12,000 20,600 3210 820 70 86 36 315
Paper mill – 800 1600 5020 610 54 9 11 0.6 97
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 41
wastewater produced at various process stages and
pollution sources are given in Tables 5, 6 and 7.
5. Fate and effects on the environment
The pollutants discharged from the pulp and paper
industry affect all aspects of the environment such as
water, air and land. Makris and Banerjee (2002)
studied the fate of the resin acid in the secondary
treatment system. Various authors at different times
reported the appearance of toxic effects on various fish
species due to exposure of pulp and paper mill efflu-
ents. Many authors reported the presence of toxic
pollutants in fish or toxic effects on fish such as
respiratory stress, mixed function oxygenase activity,
toxicity and mutagenicity, liver damage, or genotoxic
effects, and lethal effects on the fishes exposed to pulp
Table 6
Characteristics of wastewater (mg/l) at various pulp and paper processes
Process Parameters
TS SS BOD5
Wood preparation 1160 600 250
Drum debarking 2017–3171 – 480–987
Bleach kraft mill – 34 23
Newsprint mill 3750 250 –
and paper mill wastewaters (Owens et al., 1994; Vass
et al., 1996; Schnell et al., 2000b; Lindstrom-Seppa et
al., 1998; Leppanen and Oikari, 1999; Johnsen et al.,
1998; Erisction and Larsson, 2000). Baruah (1997)
reported on serious concerns related to the surface
plankton population change in Elengabeel’s wetland
ecosystem in India due to untreated paper mill effluent
discharge into the system. Yen et al. (1996) reported on
the possibility of the sub-lethal effects to the aquatic
organisms in the Dong Nai River in Vietnam due to the
effluents discharged from a pulp and paper mill.
However, there are also some contradictory reports
by other authors. Kovacs et al. (2002) reported no
significant evidence of depressed plasma steroids nor
increase in mixed function oxygenase (MFO) activity
in fish associated with pulp mill effluent. D’surney et
al. (2002) and Felder et al. (1998) indicated no
significant adverse effect in sediments, and river biota
References
COD AOX Resin
(Ag/l)Color
(Pt–Co)
– – – Nemerow and
Dasgupta (1991)
– – 20–50 Springer (2000)
– 12.5 69 – Wayland et al. (1998)
3500 – 16 1000 Tardif and Hall (1997)
Table 7
Characteristics of wastewater at various pulp and paper processes
Process Parameters References
pH TS
(mg/l)
SS
(mg/l)
BOD5
(mg/l)
COD
(mg/l)
Color
(Pt–Co)
Large mills (India) 11.0 5250 1233 983 2530 black Srivastava et al. (1990)
Small mills (India) 12.3 15,120 4890 2628 6145 DB Srivastava et al. (1990)
Digester house 11.6 51,589 23,319 13,088 38,588 16.6a Singh et al. (1996)
Combined effluent 7.6 3318 2023 103 675 1.0a Singh et al. (1996)
TMP whitewater 4.7 – 91 1090 2440 – Jahren et al. (1999)
TMP whitewater 4.7 – 105 1125 2475 – Jahren et al. (2002)
Kraft mill 8.2 8260 3620 – 4112 4667.5 Rohella et al. (2001)
Pulping 10 1810 256 360 – – Dilek and Gokcay (1994)
Kraft mill (unbleached) 8.2 1200 150 175 – 250 Nemerow and Dasgupta (1991)
Bleached pulp mill 7.5 – 1133 1566 2572 4033 Yen et al. (1996)
Bleaching 2.5 2285 216 140 – – Dilek and Gokcay (1994)
Pulp and paper 7.8 4200 1400 1050 4870 DB Mandal and Bandana (1996)
News air and land paper
deinking
8.3 450 400 16 78 – Vlyssides and
Economides (1997)
Paper making 7.8 1844 760 561 953 Black Gupta (1997)
Paper mill 8.7 2415 935 425 845 DB Dutta (1999)
Paper machine 4.5 – 503 170 723 243 Yen et al. (1996)
Paper machine 8.3 – 1032 240 – – Dilek and Gokcay (1994)
a Unit [Optical Density (O.D) at 465 nm]; ‘DB’ means dark brown; ‘LY’ means light yellow.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5842
or on fish attributable to the treated mill effluent.
Stepanova et al. (2000) reported no clear evidence of
mutagens in most of aquatic animals studied in Lake
Baikal due to Baikalsk pulp and paper mill wastewater
discharged to the lake. Wayland et al. (1998) reported
no effect on the tree shallow, which feed on the insects
downstream of the pulp mill.
Howe and Michael (1998) studied the effects of the
treated pulp mill effluent on irrigated soil in northern
Arizona, which showed serious soil chemistry change.
Dutta (1999) investigated the toxic effect of the paper
mill effluent (treated) applied to a paddy field in
Assam, India. Gupta (1997) and Singh et al. (1996)
reported high loads of organic pollutants derived from
the paper mill wastewater in Tamilnadu, and Punjab,
India, respectively. Singh et al. indicated high level of
coliform bacteria in the effluent too. However, Archi-
bald (2000) indicated that the presence of coliform
bacteria in the pulp and paper effluent did not neces-
sarily mean a health hazard to the environment unless
pathogens were observed. Skipperud et al. (1998) and
Holmbom et al. (1994) reported the presence of various
trace metals in the pulp and paper mill effluents at low
levels. King et al. (1999) reported elevated levels ofMn
accumulation in the Crayfish exposed to the paper mill
wastewater. Mandal and Bandana (1996) reported on
health impacts such as diarrhea, vomiting, headaches,
nausea, and eye irritation on children and workers due
to the pulp and paper mill wastewater discharged to the
environment. High carbon dioxide level in the pulp and
paper mill effluents as a potential source of distress and
toxicity to rainbow trout was reported by O’connor et
al. (2000).
6. Wastewater treatment
Pollution from the pulp and paper industry can be
minimized by various internal process changes and
management measures such as the Best Available
Technology (BAT). Dube et al. (2000) reported a
60% reduction in effluent BOD due to an internal
process change in Irving Pulp and Paper Limited,
Canada. The estimated data by Springer (2000)
showed that the water use in the US in 1959 was about
250 m3/adt whereas water use in 1995 was reduced to
50 m3/adt. However, the average water use for the pulp
and paper mills in India was still 200–259 m3/ton of
paper production (Gune, 2000). Several authors have
suggested internal process change as a measure to
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 43
control pollution (Reilama and Ilomaki, 1999; Webb,
1994; Dey et al., 1991). Raghuveer and Sastry (1990)
reported BOD, COD, and color reduction by internal
management measures. However, the treatment of the
wastewater by various external processes is essential.
Since pulp and paper industry discharges varieties of
pollutants, the treatment methods also vary.
6.1. Physicochemical treatment
Physicochemical treatment processes include re-
moval of suspended solids, colloidal particles, floating
matters, colors, and toxic compounds by either sedi-
mentation, flotation, screening, adsorption, coagula-
tion, oxidation, ozonation, electrolysis, reverse osmo-
sis, ultra-filtration, and nano-filtration technologies.
6.1.1. Sedimentation/flotation
Suspended matters present in the pulp and paper
wastewater are comprised primarily of bark particles,
fiber, fiber debris, filler and coating materials. Thomp-
son et al. (2001) stated that sedimentation was the
preferred option within the paper mills in the UK, and
contributed to more than 80% removal of the sus-
pended solids on an average. Rajvaidya and Markan-
dey (1998) stated that the design value of the primary
clarifier was 70–80% in average. Azevedo et al.
(1999) reported on the effect of pH on pulp settal-
ability. Gubelt et al. (2000) reported 65–95% removal
of TSS by dissolved air flotation and it was an
unstable unit. However, Wenta and Hartmen (2002)
mentioned that dissolved air flotation was able to
remove 95% of the TSS.
6.1.2. Coagulation and precipitation
Coagulation and flocculation is normally employed
in the tertiary treatment in the case of pulp and paper
mill wastewater treatment and not commonly adopted
in the primary treatment. Tong et al. (1999) and
Ganjidoust et al. (1997) carried out a comparative
study of horseradish peroxide (chitosan) and other
coagulants such as (Al2(SO4)3), hexamethylene di-
amine epichlorohydrin polycondensate (HE), poly-
ethyleneimine (PEI), to remove adsorbable organic
halides (AOX), total organic carbon (TOC), and color.
The authors indicated that modified chitosan was far
more effective in removing these pollutants than other
coagulants. Wagner and Nicell (2001) investigated the
treatment of foul condensate, defined by phenolic
compounds, and toxicity using microtox assay from
kraft pulping by horseradish peroxide and H2O2 and
found a total phenol reduction below 1 mg/l and
toxicity (microtox assay) reduction by 46%. Dilek
and Gokcay (1994) reported 96% removal of COD
from the paper machine, 50% from the pulping, and
20% for bleaching effluents by using alum as a
coagulant. Rohella et al. (2001) stated polyelectrolytes
were better than the conventional coagulant alum to
remove turbidity, COD, and color. Sheela and Distidar
(1989) reported on black liquor treatment by precipi-
tation with CaSO4�2H2O in the presence of CO2. The
removal of dissolved solids was reported to be 63%.
However, Wang and Pan (1999) reported that the use
of coagulants such as polyethylene oxide (PEO),
worsened the settlability and increased COD levels,
turbidity, and suspended solids of the treated effluent
when the dose was between 25 and 250 ppm. Cher-
noberezhskii et al. (1994) reported that coagulation
with aluminum sulfate or modified adsorbents was the
best option for color removal from the sulfate and
sulfite wood pulp and paper industry.
6.1.3. Adsorption
Murthy et al. (1991) reported a high removal of
color by activated charcoal, fuller’s earth, and coal ash.
Shawwa et al. (2001) reported 90% removal of color,
COD, DOC, and AOX from bleached wastewater by
the adsorption process, using activated coke as an
adsorbent. Sullivan (1986) concluded that the waste-
water produced by the Union Camp Facility at Frank-
lin, VA, can be treated by activated carbon and ion
exchange to reduce color and chloride to levels ac-
ceptable for reuse. Das and Patnaik (2000) investigated
the lignin removal efficiency of the blast furnace dust
(BFD) and slag by the adsorption mechanism. Their
study showed 80.4% and 61% removal of lignin by
BFD and slag, respectively. Narbaitz et al. (1997)
reported that PACTk process was an effective process
to remove AOX from the kraft mill effluent to meet
Ontario’s year 2000 regulation (AOX: 0.8 kg Cl/adt of
production).
6.1.4. Chemical oxidation
Balcioglu and Ferhan (1999) reported on photo-
catalytic oxidation of kraft pulp bleaching wastewater
showing that the removal largely depended on the
D. Pokhrel, T. Viraraghavan / Science of the44
concentration of COD and chloride below a certain
level. Zamora et al. (1998) reported on the use of
horseradish peroxide to decolorize kraft effluent by
50% within three hours of reaction time. The degra-
dation of phenolic and polyphenolic compounds pres-
ent in the bleaching effluent was studied using
advanced oxidation systems such as photocatalysis
with O2/ZnO/UV, O2/TiO2/UV, O3 and O3/UV. The
authors concluded that O2/ZnO/UV and O2/TiO2/UV
were the best systems to oxidize the effluent in a short
period of time. Perez et al. (2002c) reported that the
combination of Fenton and photo-fenton reactions
proved to be highly effective for the treatment of
bleaching kraft mill effluent. Verenich et al. (2000)
reported on the improvement in biodegradability of an
effluent from 30% to 70% by wet oxidation method.
Hassan and Hawkyard (2002) studied the removal of
color by combined oxidation with ozone and Fenton’s
reagent and stated that 100% color removal was
achieved at a pH of 4–5 in the case of ferral (derived
from natural clay sources, which contains 2% ferric
sulfate and 6% aluminum sulfate) and ferric sulfate.
Dufresne et al. (2000) reported on the oxidation of
total reduced sulfur (TRS) giving odor free products
by catalytically enhanced oxidation.
6.1.5. Membrane filtration
Jonsson et al. (1996) reported on the treatment of
paper coating color effluent treatment by membrane
filtration suggesting that the composition of the color
had a significant influence on the performance. Mem-
brane separation techniques were reported to be
suitable for removing AOX, COD, and color from
pulp and paper mills (Zaidi et al., 1992; Afonso and
Pinho, 1991, Falth, 2000). De Pinho et al. (2000)
compared the efficiency of (1) ultrafiltration and (2)
ultrafiltration plus dissolved air flotation. The results
showed 54%, 88%, 100% removal of TOC, color,
and SS, respectively by ultrafiltration alone. Ultrafil-
tration plus dissolved air flotation resulted in 65%,
90% and 100% removal of TOC, color, and SS,
respectively. Dube et al. (2000) reported that 88%
and 89% removal of BOD, and COD, respectively
was achieved by reverse osmosis (RO). Merrill et al.
(2001) stated that membrane filtration (MF), and
granular membrane filtration (GMF) were suitable
for removing heavy metals from the pulp and paper
mill wastewaters.
6.1.6. Ozonation
Yeber et al. (1999) reported that a substantial
removal of COD, TOC, and toxicity from pulp mill
effluent and increased biodegradability of the effluent
were achieved after treatment with ozone. Korhonen
et al. (2000) reported a 90% removal of ethylenedia-
minetetraacetic acid (EDTA) and a 65% removal of
COD by ozone treatment of the pulp mill effluent.
Hinck et al. (1997) reported that neither EDTA nor
diethylene triamine pentaacetic acid (DTPA) are bio-
degraded in aerobic conditions. Oeller et al. (1997)
reported high removal of COD and DOC from the
pulp effluent by ozone treatment. Freire et al. (2000)
reported a 12% reduction of total organic carbon, total
phenols reduced to 70%, and effluent colors to 35% of
bleached pulp mill effluent after 60 min of ozonation.
Several authors reported on toxic compounds, COD,
and color removal by ozone treatment (Hostachy et
al., 1997; Zhou and Smith, 1997; Yamamoto, 2001).
Roy-Arcand and Archibald (1996) reported that bio-
treated kraft effluents yielded a substantial decrease in
the biologically recalcitrant residual adsorbable or-
ganic halogens (AOX), converted COD to BOD and
yielded large decrease in color. Laari et al. (2000)
investigated the removal of lipophilic wood extrac-
tives from TMP wastewater by ozonation. The authors
indicated that a high dosage of ozone (100–300 mg/
dm3) was required to remove 50% of lippphilic wood
extractives. Korhonen and Tuhkanen (2000) reported
that ozone doses of 0.2 mgO3/initial mgCOD elimi-
nated over 90% resin acid. Torrades et al. (2001)
reported high removals of TOC, COD, AOX, and
color from bleached kraft mill effluent (BKME1)
using heterogeneous photocatalysis and ozone treat-
ment. Sevimli and Sarikaya (2002) reported a 95–
97% color removal for high doses of ozone in 15 min
of ozonation. Kallas and Munter (1994) suggested
post treatment of bleached mill effluent by ozonation
and adsorption.
6.2. Biological treatment
6.2.1. Aerobic treatment
6.2.1.1. Activated sludge process. The performance
variation of the activated sludge due to the changes in
pH, temperature, and H2O2 and DTPA was reported
by Ginkel et al. (1999), Norris et al. (2000), and
Total Environment 333 (2004) 37–58
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 45
Larisch and Duff (1997, 2000), respectively. Knudsen
et al. (1994) reported a high reduction of BOD and
soluble COD by a two-stage activated sludge process.
Shere and Daly (1982) claimed that TMP wastewater
was readily degradable by the activated sludge pro-
cess. Hansen et al. (1999) suggested upgrading the
activated sludge plant by the addition of Floobeds
(floating biological bed) in series that increased COD
and BOD removal from 51% to 90% and 70% to
93%, respectively. Chandra (2001) reported efficient
removal of color, BOD, COD, phenolics, and sulfide
by microorganisms such as Pseudomonas putida,
Citrobacter sp., and Enterobacter sp. in the activated
sludge process. Mohamed et al. (1989) reported
removal of chlorinated phenols, 1,1-dichlorodimethyl
sulfone (DDS), and chlorinated acetic acids in an
oxygen activated sludge effluent treatment plant.
Demirbas et al. (1999) reported AOX removal by
the activated sludge process. Junna and Ruonala
(1991) reported 90% BOD7, 70% COD, 40–60%
AOX, and 60–95% chlorinated phenols removal by
the activated sludge process. Bryant et al. (1992)
reported AOX removal of 46% on average from
two activated sludge systems studied. Andreasan et
al. (1999) suggested the addition of an anoxic selector
before the activated sludge plant to improve the
sludge settlability problem. Raghuveer and Sastry
(1991) reported that a minimum of mixed liquor
suspended solids (MLSS) of 2000–2500 mg/l and
an aeration time of 6–8 h were required to remove
83–88% of BOD. High removals of BOD, COD,
AOX, and chlorinated phenolics have been achieved
in the activated sludge process (Saunamaki, 1997;
Schnell et al., 2000a). Kennedy et al. (2000) reported
that the activated sludge was successful in removing
nearly all detectable Microtoxk toxicity from
bleached kraft pulp mills at low level whereas the
PACTk was slightly better in removing highly toxic
concentrated effluents.
6.2.1.2. Aerated lagoons. Stuthridge and Mcfarlane
(1994) stated that 70% removal of the AOX from the
aerated lagoon was attributed to a short residence
time section of the treatment system where the
chlorinated stage effluents were mixed with general
mill wastewaters. The effect of simple mixing was
reported to be responsible for 15–46% removal.
Bryant et al. (1997) reported 67% removal of am-
monia from black liquor spill at temperatures of 22–
35 jC, pH near 7.3 in an aerated lagoon. Chernysh
et al. (1992) reported large variations in AOX and
TOC removal in a controlled batch study of bleached
kraft effluent in an operating lagoon under both
aerobic and anaerobic conditions. Welander et al.
(1997) reported COD removal of 30–40% in a full-
scale lagoon and 60–70% in a pilot-scale plant.
Stuthridge et al. (1991) reported 65% removal of
AOX from bleached kraft pulp and paper mill
effluent. Junna and Ruonala (1991) reported removal
of BOD7 ranging between 50% and 75% and chlo-
rinated phenolics 10–50% by an aerated lagoon.
Achoka (2002) reported that an oxidation pond
removed chemical compounds greater than 50%.
Schnell et al. (2000a) reported removals of BOD,
AOX, chlorinated phenolics, and polychlorinated
phenolics respectively from an aerated lagoon.
6.2.1.3. Aerobic biological reactors. Many authors
have reported high removals of organic pollutants of
kraft mill wastewater by sequencing batch reactor
(SBR) treatment (Franta et al., 1994; Franta and
Wilderer, 1997; Milet and Duff, 1998). Reid and
Simon (2000) reported 100% removal of methanol
and 90% removal of CODsol by SBR. Substantial
removal of COD, TOC, BOD (Magnus et al.,
2000a), lignin and resin acids (Magnus et al.,
2000b) of TMP wastewater using high rate compact
reactors (HCRs) at a retention time of 1.5 h had
been reported. Removal of COD by a moving bed
bifilm reactor (MBBR) had been demonstrated (Jah-
ren et al., 2002; Borch-Due et al., 1997). Magnus et
al. (2000c) reported 93% and 65% removal of BOD
and COD, respectively by a biological compact
reactor. Berube and Hall (2000) showed that approx-
imately 93% removal of TOC could be achieved by
a membrane bioreactor. Asselin et al. (2000) con-
cluded that suspended carrier biofilm reactor (SCBR)
was highly efficient in removing chronic toxicity
from the effluent. Rovel et al. (1994) achieved
76%, 62%, 81%, and 48% removal of BOD,
COD, SS, and AOX, respectively, using a biofilter.
Rudolfs and Amberg (1953) demonstrated that aer-
obic treatment of whitewater (high strength) was
able to achieve 70–80% removal of BOD. Typical
efficiencies of aerobic systems are presented in
Table 8.
Table 8
Typical efficiencies of aerobic systems (Springer, 2000; *Kantar-
djieff and Jones, 1997)
System Aeration
time (day)
Organic loading
(lb BOD/1000 ft3)
Efficiency
(%)
Aerobic biofilters
(sulfite mill)*
– 3.4 kg/m3/day 74–92
Aerobic biofilters
(TMP)*
– – 74–90
Aerobic stabiliztion
basin
5–10 50 80–90
Activated sludge 3–8 h 50 80–85
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5846
6.2.2. Anaerobic treatment
An anaerobic process is considered more suitable
to treat high strength organic effluents. Before 1980s,
the treatment of pulp mill effluents by anaerobic
means was limited, as most of the pulp mill effluents
at that time were less concentrated (300–2000 mg/
l BOD) (Bajpai, 2000) and were not suitable for
anaerobic treatment. Anaerobic filter, upflow sludge
blanket (UASB), fluidized bed, anaerobic lagoon, and
anaerobic contact reactors are anaerobic processes,
that are commonly used to treat pulp and paper mill
effluents. Pretreatment of the kraft mill black liquor
was investigated by Poggi-Varaldo et al. (1996) and
they reported that continuous anaerobic treatment of
wastewater contaminated with black liquor was fea-
sible at low to medium loading rates, with a total COD
removal of 48–80% and biodegradable COD reduc-
tion of 87–96%. Jahren et al. (1999) compared
anaerobic and aerobic treatment for TMP mill effluent
and found that 84% and 86% removal of COD from
anaerobic and aerobic treatment systems, respectively,
was achieved. Rajeshwari et al. (2000) reported that
chlorine bleaching effluents were not suitable for
anaerobic treatment due to their low biodegradability
and presence of toxic substances that affects metha-
nogens. Sandquist and Sandstrom (2000) developed a
new treatment technology [the process consists of
three steps: (1) stripping of sulfides and other volatile
components from condensate; (2) regenerative ther-
mal oxidation of stripper off gases; (3) adsorption of
sulfur oxide] to treat foul condensate (sulfide) from
the black liquor. Removal efficiency for foul conden-
sate was reported to be more than 99% at a pH of 4
and removal of methanol was 90% at a low liquid/gas
ratio. Jackson-Moss et al. (1992) found 50% removal
of COD and color by anaerobic biological granular
activated carbon. Dufresne et al. (2001) observed that
undiluted foul condensates at Windsor mill were toxic
to anaerobic biomass. Chen and Horan (1998) stated
that COD, and sulfate removals of 66% and 73%,
respectively, were obtained using a UASB reactor
with a hydraulic retention time of 6 h. Peerbhoi
(2000) investigated anaerobic treatability of black
liquor by a UASB reactor in her study at the Univer-
sity of Roorkee, India. The author concluded that
anaerobic biological treatment of black liquor was
not feasible, as the pollutants were not readily de-
gradable. Perez et al. (1998) evaluated two anaerobic
systems (anaerobic filters and fluidized bed) in labo-
ratory-scale reactors and reported that 81.5% organic
removal efficiency was obtained in the case of fluid-
ized bed with porous packing and 50% removal was
obtained in the case of anaerobic filters on corrugated
plastic tubes. Rajeswori et al. (2000) reported a 50%
reduction of BOD of debarking wastewater by a
fluidized bed reactor. Thompson et al. (2001) reported
that COD removal efficiency of 80% was constantly
achievable but the residual COD was around 800 mg/
l meaning that additional treatment was essential.
Schnell et al. (1992) concluded that anaerobic treat-
ment systems were less suitable for treatment of
sulfite-spent liquor compared to an aerobic system.
The anaerobic treatability of different processes are
given in Table 9.
6.3. Fungal treatment
Taseli and Gokcay (1999) isolated fungal specie
(Pencillium sp.) which was able to remove 50% of the
AOX, and color from the soft-wood bleachery efflu-
ents in a contact time of 2 days. Several authors
reported on the capacity of different fungal species
to remove color from kraft mill effluent (Gokcay and
Dilek, 1994; Duran et al., 1994; Sakurai et al., 2001).
Prasad and Gupta (1997) reported on a substantial
reduction of color and COD by the use of white rot
fungi T. versicolor and P. chrysosporium. Saxena and
Gupta (1998) showed that white-rot fungi P. chrys-
osporium in combination with other white-rot fungi
(P. sanguineus, P. ostreatus and H. annosum) and with
the use of the surfactants were able to remove color,
COD, and lignin content. Choudhury et al. (1998)
found that lignin, BOD, COD and color removal were
achieved to the extent of 77%, 76.8%, 60%, and 80%,
Table 9
Anaerobic degradability of pulp and paper mill effluent (Rintala and Puhakka, 1994)
Wastewater from COD (mg/l) Anaerobic
degrad. (%)
Inhibitors
Wet debarking 1300–4100 44–78 Resin acids
Thermomechanical
pulping
1000–5600 60–87 Resin acids
Chemothermomechanical
pulping
2500–13,000 40–60 Resin acids,
fatty acids, sulfur, DTPA
NSSC-spent liquor 40,000 nr Tannins
NSSC-condensate 7000 nr Sulfur, ammonia
Kraft condensate 1000–33,600 83–92 Sulfur, resin acids,
fatty acids, terpenes
Spent condensate 7500–50,000 50–90 Sulfur, organic sulfur
Chlorine bleaching 900–2000 30–50 Chlorinated phenols,
resin acids
Sulfite spent liquor 120,000–220,000 nr nr
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 47
respectively, by the fungal specie Pleurotus ostreatus.
Zhang et al. (2000a) examined the removal of most of
the detrimental organics from whitewater by com-
bined enzyme and fungal treatment. The removal of
lignin was >90% whereas resin and fatty acids were
reduced by 20%. Zhang et al. (2000b) showed that
fungus such as T. versicolor and fungal culture filtrate
(FCF) obtained from these organisms were able to
efficiently degrade the dissolved and colloidal sub-
stances. Mendonca et al. (2002) suggested fungal
pretreatment of P. taeda wood chips by C. subvermis-
pora. The performance of fungal treatment is summa-
rized in Table 10.
6.4. Integrated treatment processes
An integrated or hybrid system is designed to take
advantage of unique features of two or more process-
es. A combination of coagulation and wet oxidation
removed 51% of COD (Verenich et al., 2001); and
Table 10
Performance of fungal treatment
Treatment process Parameters
COD Lignin
Influent
(mg/l)
%
Removal
Influent
(mg/l)
White rot fungi 39,012 40.74 2870
White rot + surfactants 39,012 75.35 2870
White rot (T. versicolor) – 77.7 –
White rot (P. chrysosporium) – 79.4 –
83% of color and 75% of lignin (Verenich and Kallas,
2001). A combination of ozone and biofilm reactor
removed 80% COD (Helble et al., 1999). A combi-
nation of chemical oxidation with ozone removed
90% of wood extractives and 50% of the COD from
TMP wastewater at 150 jC (Laari et al., 1999).
Athanasopoulos (2001) suggested post treatment
methods such as electrolysis or ozonation to reduce
COD, and NH4+–N concentration to the permitted
level. Nakamura et al. (1997) reported on efficient
degradation of lignin using a combined treatment of
ozone and activated sludge process. Jokela and Keski-
talo (1999) reported that a combination of dissolved
air flotation and chemical precipitation removed 93%
SS, 50% BOD7, 57% COD, 92% phosphorus, and
52% nitrogen.
A combination of activated sludge and with
ozonation (as tertiary treatment) removed 87–97%
COD, and 97% BOD (Schmidt and Lange, 2000).
Kabdash et al. (1996) showed that a combination of
Reference
Color
%
Removal
Influent
(mg/l)
%
Removal
16.38 34,940 34.49 Saxena and Gupta (1998)
65.84 34,940 81.29 Saxena and Gupta (1998)
– 1875 93.8 Prasad and Gupta (1997)
– 1875 83.5 Prasad and Gupta (1997)
Table 11
Performance of physicochemical treatment processes
Treatment process Parameters Reference
TSS COD TOC AOX Color Lignin/Resin*
or Fatty# acid
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(Pt–Co)
%
Removal
Influent
(mg/l)
%
Removal
Coagulation:
Polyelectrolyte 3620 100 4112 55.65 – – – – 4667.5 82.58 480 98.91 Rohella et al. (2001)
Chitosan – – – – – 70 – – – 90 – – Ganjidoust et al. (1997)
PE/PEI – – – – – 30 – – – 80 – – Ganjidoust et al. (1997)
Alum – – – – – 40 – – – 80 – – Ganjidoust et al. (1997)
Adsorption:
Charcoal #1 – – – – – – – – 3.9 mg/l 98.13 – – Murthy et al. (1991)
Coal ash #2 – – – – – – – – 3.9 mg/l 98.5 – – Murthy et al. (1991)
Fuller earth #3 – – – – – – – – 3.9 mg/l 99.21 – – Murthy et al. (1991)
Activated coke #4 – – 2126 >90 – – 80.2 >90 2300 >90 – – Shawwa et al. (2001)
Oxidation:
(Wet oxidation)
– – 10,000~19,000 80 3500~4100 80 – – – – Verenich et al. (2000)
(Ozone + Fenton) – – – – – – – – – ~100 Hassan and
Hawkyard (2002)
Ozonation:
Ozone +UV – – ~550 82 – – – – – – Oeller et al. (1997)
Photocat. + ozone – – 515 85 306 88 27.7 92.5 250 100 Torrades et al. (2001)
Photocat. + ozone – – 3700 57.5 1380 38 69.8 50 7030 65 Torrades et al. (2001)
Membrane:
Ultrafiltrtion – – – 85–90 – – 85–91 93–98 Zaidi et al. (1992)
Nanofiltration – – – – – – – 93–96 99.2–99.9 Zaidi et al. (1992)
Dissolved air +UF 397 100 – – 828 65 – – 1747 90 De Pinho et al. (2000)
Microfiltration +UF 397 100 – – 828 54 – – 1747 88 De Pinho et al. (2000)
(#1) Charcoal dose 0.4 g/l and pH 2.0; (#2) Coal ash dose 12 g/l and pH 2.0; (#3) Fuller earth dose 4 g/l and pH 2.0; (#4) activated coke dose 15,000 mg/l.
D.Pokhrel,
T.Vira
raghavan/Scien
ceoftheTotalEnviro
nment333(2004)37–58
48
Table 12
Performance of aerobic biological treatment processes
Treatment process Parameters Reference
TSS BOD COD AOX Chlorinated phenolics
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Activated sludge
Paper mill 1435 90.6 512 94.2 1210 82.4 – – – – Saunamaki (1997)
Pulp mill 738 76.4 336 93.8* 1192 57.1 11.7 55 – – Saunamaki (1997)
Kraft mill
(period 1)
– – 270 >95* 660 (F) 60 22.5 36 0.255 74 Schnell et al.
(2000a)
(period 2) – – 270 >98 660 (F) 70 22.5 40 0.255 83 Schnell et al.
(2000a)
Pulp and
paper mill
– – – 96.63 – 96.8 – – – 96.92 Chandra (2001)
Paper mill – – 1000 99 1533a 85 – – – – Knudsen et al.
(1994)
Aerobic stabilization basin
Kraft mill
(period 1)
– – 270 >95 660 (F) 62 22.5 53 0.255 85 Schnell et al.
(2000a)
(period 2) – – 270 >98 660 (F) 73 22.5 55 0.255 86 Schnell et al.
(2000a)
Kraft mill – – – – – 20–65 – 17–70 – – Chernysh et al.
(1992)
(1) ‘‘F’’ means fraction of COD or soluble COD.
(2) Period 1: operating conditions for activated sludge-HRT 2 days, SRT 25 days, Temp. 30 jC, VSS 1800 mg/l.
(3) Period 1: operating conditions for aerated stabilization basin-HRT 15 days, SRT 15 days, Temp. 30 jC, VSS 60 mg/l.
(4) Period 2: operating conditions for activated sludge-HRT 1 day, SRT 25 days, Temp. 30 jC, VSS 2800 mg/l.
(5) Period 2: operating conditions for aerated stabilization basin-HRT 15 days, SRT 15 days, Temp. 20 jC, VSS 70 mg/l.a Means soluble COD and * means BOD7.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 49
chemical and biological methods (bioferic) resulted
in 40–50% additional removal of COD compared to
the activated sludge system. Jahren and Oedegaard
Table 13
Performance of biological treatment processes
Treatment process Parameters
BOD COD Metha
Influent
(mg/l)
%
Removal
Influent
(mg/l)
%
Removal
Influe
(mg/l)
Biological reactors
HRC (TMP Mill) 1150 98 3340 79 –
Total plant
efficiency
1490 99 5000 86 –
MBBR
(HRT 4.5 hrs)
– 65–75 – 85–95 –
SBR – 98 – 85–93 –
Anaerobic (GAC) – – 1400 50 –
Kraft mill Windsor 1429a 69 2036a 59 1095a
a Unit in g/d.
(1999) found that Kaldnes (anaerobic followed by
aerobic) moving bed biofilm reactor at 55 jC re-
moved about 60% of soluble COD from TMP
Reference
nol Color
nt %
Removal
Influent
(mg/l)
%
Removal
– – – Magnus et al. (2000a)
– – – Magnus et al. (2000a)
– – – Borch-Due et al. (1997)
– – – Franta and Wilderer (1997)
– 1300 50 Jackson-Moss et al. (1992)
84 – – Dufresne et al. (2001)
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5850
whitewater. A combined anaerobic–aerobic treat-
ment system was suggested to treat bleached kraft
pulp and paper mill effluents (Duncan and Thia,
1992; Wang et al., 1997). Lescot and Jappinen
(1994) showed that a combination of an aerated
lagoon and a secondary clarifier was able to treat
bleached kraft mill effluent in Finland resulting in
87%, 96%, 65%, 53%, and 22% removal of SS,
BOD7, COD, AOX, and color, respectively. Carlson
et al. (2000) reported that 77%, 98–99%, 72%, and
81% removal of COD, BOD, TN, and TP, respec-
tively, was achieved after upgrading the aerated
Table 14
Selected anaerobic process performance (Bajpai, 2000)
Mill location Wastewater source Lo
(kg
Anaerobic contact reactor
Hylte Bruk
AB, Sweden
TMP,
groundwood, deink
2.
SAICA,
Zaragoza, Spain
Waste paper alkaline
cooked straw
4.
Hannover paper,
Alfred, Germany
Sulfite effluent
condensate
4.
Niagara of Wisconsin
of USA
CTMP 2.
SCA Ostrand,
Ostrand, Sweden
CTMP 6
Alaska Pulp
Corporation, Sitka
Sulfite condensate,
bleach caustic and
pulp whitewater
3
Upflow anaerobic sludge blanket
Celtona, Holland Tissue 3
Southern paper
converter, Australia
Wastepaper 10
Davidson,
United Kingdom
Linerboard 9
Chimicadel,
Friulli, Italy
Sulfite
condensate
12.
Quesnel River
Pulp, Canada
TMP/CTMP 18
Lake Utopia
Paper, Canada
NSSC 20
EnsoGutzeit, Finland Bleached
TMP/CTMP
13.
McMillan Bloedel,
Canada
NSSC/CTMP 15
Anaerobic filter:
Lanaken, Belgium
CTMP 12.
Anaerobic fluidized
bed: D’ Aubigne, France
Paperboard 35
basin at Monsteras mill. The system comprised of
an anoxic selector, an aerated basin, and a secondary
clarifier in series. The removals of extractives, resin
and fatty acids were 96% and 98%, respectively,
whereas the system reduced Microtoxk by 99%.
Welander et al. (2000) reported on the performance
of an aerobic biological process called LSP (low
sludge production) to lower the biological sludge by
80–90%. The system configuration was primary
clarifier, aeration basin, and secondary clarifier. A
combination of physicochemical, biological, and ef-
fluent polishing in the aerated lagoon removed 98–
ading rate
COD/m3/d)
BOD5
(mg/l)
COD
(mg/l)
TSS
(mg/l)
BOD5
Removal%
COD
Removal%
5 1300 3500 520 71 67
8 10,000 30,000 – 94 66
2 3000 6000 – 97 85
7 2500 4800 3300 96 77
3700 7900 – 50 40
3500 10,000 – 85 49
600 1200 – 75 60
– 10,000 – > 80 > 80
1440 2880 – 90 75
5 12,000 15,600 – 90 80
3000 7800 – 60 50
6000 16,000 – 80 55
5 1800 4000 – 75 60
7000 17,500 – 80 55
7 4000 7900 – 85 70
1500 3000 – 83.3 72.2
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 51
99% BOD, 91% COD, 97% SS, and 90% color of a
pulp and paper mill in Brazil (Foelkel, 1989). Rusten
et al. (1994) reported that a combination of a biofilm
reactor followed by one anaerobic and two aerobic
reactors was found to remove 50% COD, 80–90%
BOD7, 50% AOX, 90% ClO3. Shaw et al. (2002)
showed that a combination of aerobic reactor fol-
lowed by anaerobic reactor removed 94% color, and
66% TOC. Schnell et al. (1997) found that 87–95%,
70–77%, and 80–94% removal of BOD, COD, and
resin and fatty acids was provided by biological
treatment. Tardif and Hall (1997) reported 100%,
96%, 76%, and 34% removal of resin acid (RA),
fatty acid (FA), dissolved chemical oxygen demand
(DCOD), and total dissolved solids (TDS), respec-
tively at temperatures 20–40 jC by an SBR. An
MBR removed 100% RA and FA, 84% DCOD, and
37% TDS at 40–50 jC. Malmquist et al. (1999)
reported a COD removal of 70–90% of whitewater
by biological treatment. Badar (1996) suggested a
number of methods to improve the integrated paper
mill wastewater effluent treatment: (1) increasing the
capacity of the aeration basin; (2) installing an extra
dissolved air flotation clarifier; (3) adding chlorine
gas to improve bulking of sludge problem and (4)
injecting oxygen to treat BOD during heavy rain and
flooded conditions. Graves and Joyce (1994)
reviewed the ability of biological treatment systems
to remove chlorinated organic compounds discharged
from pulp and paper industry. AOX removal of 32%
(aerated lagoon) and 10–65% by activated sludge
plant was reported. Gupta et al. (2001) isolated
bacterial specie Aeromonas formicans suitable to
treat black liquor from kraft pulp and paper mills.
Performances of various treatment processes are
summarized in Tables 11–14.
7. Discussion
The literature review showed that an internal
process change is one of the options to be adopted
by the pulp and paper industry to reduce the pollution
at the source. A recent comprehensive study carried
out in a large number of pulp and paper mills in the
US found that the effluent discharge has been reduced
by 30%; TSS and BOD have been reduced by 45%
and 75%, respectively (Das and Jain, 2001) even
when the production has been increased. Trotter
(1990a,b) evaluated biotechnological applications
such as genetic modification of plant, biopulping,
and biobleaching to reduce chlorinated organic com-
pounds as an emerging technology for internal pollu-
tion control. Enzyme treatment for pulp dissolving,
improving tensile properties by treating mechanical
pulp with white rot organisms and enzymatic beating
of chemical pulps, hemicellulose, and decolorization
by white rot fungi were given as possible biotechno-
logical options.
Among the various treatment processes currently
used for pulp and paper effluent treatment, only a few
are commonly adopted by pulp and paper industry
especially for tertiary treatment. Some of the treatment
processes such as ozonation, fenton’s reagent, adsorp-
tion, and membrane technology are efficient but are
more expensive. Sedimentation is the most commonly
adopted process by the pulp and paper industry to
remove suspended solids. The performance data given
by Springer (2000) showed 80–90% removal of
initial suspended solids from most of the mills except
a deinking mill. Flotation is also commonly used in
the pulp and paper industry but most of the time as a
tertiary treatment. Coagulants are a preferred option
for removing turbidity and color from the wastewater.
Reported results have shown that they are also capable
in reducing COD, TOC, and AOX to some extent.
Among the coagulants, modified chitosan showed the
highest performance for color and TOC removal.
Polyelectrolytes are better than alum and they produce
less sludge and pose less problems with sludge
dewaterability than alum. Adsorption processes are
useful to remove color, COD, and AOX. They are
rather expensive and it is not known whether the pulp
and paper industry are employing them widely. How-
ever, laboratory-scale experiments are usually
reported. Activated charcoal, fuller’s earth, and coal
ash showed better results for color removal. Activated
coke alone was able to remove 90% of the COD,
AOX, DOC, and color.
Chemical oxidants such as ozone + photocatalysis,
and ozone + UV are reported to be efficient in
removing COD and TOC and color. However, the
efficiency largely depends upon the concentration of
the COD. Ozone alone is able to remove 90% of
EDTA and AOX, and over 80% of COD. However,
it is rather expensive (Perez et al., 2002b). Ozonation
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5852
is not commonly adopted in most countries, not even
in Europe but it is emerging in North America.
Membrane processes are efficient in reducing over
90% of color, TSS, and AOX in most of the cases.
Fouling of membranes is a problem in the case of
soft wood effluent treated by membrane filtration. In
secondary treatment processes, activated sludge is
the most commonly used. UASB and fluidized beds
are also gaining in use recently. The problem with
activated sludge is sludge bulking. Reported results
have shown that activated sludge can remove all
types of the pollutants pertaining to the pulp and
paper industry. However, the removal of AOX is
below 50%, BOD around 95% in most of the mills,
and COD removal averages around 70%. This sys-
tem is also efficient in removing chlorinated phenolic
compounds (over 75%) most of the time. Dalentoft
and Thulin (1997) reported that Kaldnes (anaero-
bic + aerobic) process in series with an activated
sludge, could be an efficient, stable, and a compet-
itive combination process, considering both invest-
ment and operating costs. Aerated lagoons are
efficient in removing BOD over 95% in most of
the reported results. COD removals are moderate
between 60% and 70%, AOX around 50%, and a
high removal (85%) for chlorinated phenolics. An-
aerobic contact reactors are efficient in removing
biodegradable organic compounds such as BOD,
and COD. The performance data from various mills
showed that anaerobic contact reactors were able to
remove over 90% of BOD and 65% of COD in most
of the cases. Anaerobic filters and fluidized bed
reactors are suitable in reducing organic pollutants
only. Both the reactors achieve almost same efficien-
cy in terms of BOD (>80%), and COD (>70%)
removal (refer to Table 14 for details). UASBs are
able to remove over 80% of BOD and 50–80% of
COD in most of the mills (refer to Table 14 for
details). Fungi are efficient in removing especially
color and COD from the pulp mill wastewater.
Removal of color using white rot fungi was above
80% in most of the reported cases and COD removal
was above 75%. White rot fungi particularly P.
chrysosporium and C. versicolor are suitable for
efficient degradation of the refractory material (Baj-
pai and Bajpai, 1994). The reported results have
shown that high removals are achieved in the case
of the combination of two or more physicochemical
processes or combination of physicochemical and
biological processes. The confirmation of the reported
results, their applicability in the real field, and eco-
nomic evaluations are very important in adopting the
process. For example, the anaerobic treatment process
for pulp and paper mill effluents is still in an initial
application phase.
However, comprehensive evaluations made by var-
ious authors lead to a better understanding of the
various treatment processes and their adaptability.
For example, Jemaa et al. (2000) stated that chemical
precipitation, evaporation, membrane technology, and
ion exchange were the established options for the
removal of colloids and metal ions. Perez et al.
(2002a) conducted an economic evaluation of various
advanced oxidation processes to remove organic con-
taminants. Ozonation was stated to be effective but
rather an expensive process. Rintala and Puhakka
(1994) stated that operation costs of the activated
sludge was about three times greater than that of
anaerobic systems. Bajpai (2000) presented compara-
tive costs of the anaerobic and activated sludge treat-
ment, which showed that activated sludge was almost
twice as expensive as anaerobic reactors. The recent
paper by Perez et al. (2002b) reported a high efficiency
of COD and TOC removal when iron ion was used
with ozone/UV treatment system. The authors showed
that the presence of iron ion in the ozone/UV treatment
brought a complete removal of COD in 90 min while
TOC removal was higher than 90%. The report stated
that the overall cost was reduced by 50%, which is
encouraging news for the industry. Mobius and
Cordes-Tolle (1994) suggested that sand filters, bio-
filters, low capacity trickling filters, flocculation and
precipitation with inorganic salts in combination with
filtration or flotation are the emerging systems for
adoption by pulp and paper mills.
8. Conclusions
Based on the above literature review, the following
conclusions are drawn:
(i) Both aerobic and anaerobic treatment systems
are feasible to treat wastewater from all types
of pulp and paper mills except that bleaching
kraft effluents are less suitable for treatment by
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 53
anaerobic means, as they are more toxic to
anaerobic bacteria.
(ii) The anaerobic treatment of high strength
wastewater requires further treatment as it
contains high residual COD.
(iii) A combination using an anaerobic process
followed by an aerobic treatment system is a
better option, as it can make use of the
advantages of both the treatment processes.
(iv) Color is removed efficiently by fungal treat-
ment, coagulation, chemical oxidation, and
ozonation.
(v) Chlorinated phenolic compounds and AOX can
be removed by adsorption, ozonation and
membrane filtration.
(vi) Combinations of two or more physicochemical
processes produce a high removal of toxic
pollutants.
(vii) Combinations of physicochemical and biolog-
ical treatment processes with optimization of
the process provide a long-term solution for
pulp and paper mill effluent treatment.
(viii) More studies are needed on the removal of
AOX and chlorinated phenolic compounds.
References
Achoka JD. The efficiency of oxidation ponds at the kraft pulp
and paper mill at Webuye in Kenya. Water Res 2002;36:
1203–12.
Afonso MD, Pinho MN. Membrane separation processes in pulp
and paper production. Filtr Sep 1991;28(1):42–4.
Andreasan K, Agertved J, Petersen JO, Skaarup H. Improvement
of sludge settleability in activated sludge plants treating efflu-
ent from pulp and paper industries. Water Sci Technol 1999;
40(11–12):215–21.
Archibald F. The presence of coliform bacteria in Canadian pulp
and paper mill water systems—a cause for concern? Water Qual
Res J Can 2000;35(1):1–22.
Asselin C, Collin D, Graff S. Effluent treatment for chronic toxicity
removal with the suspended carrier biofilm reactor. Tappi Inter-
national Environmental Conference and Exhibit. Denver CO,
vol. 2. Norcross, GA 30092, USA: Technical Association for
Pulp and Paper Industry (TAPPI); May 2000. p. 805–11.
Athanasopoulos NS. Use of various processes for pilot plant treat-
ment of wastewater from a wood processing factory. J Chem
Technol Biotechnol 2001;76:246–50.
Azevedo MAD, Drelich J, Miller JD. The effect of pH on pulping
and flotation of mixed office wastepaper. J Pulp Pap Sci 1999;
25(9):317–30.
Badar TA. Wastewater treatment at pulp and paper mills effluent
compliance improvements at a newsprint facility. Asia Pac Tech
Monit 1996;13(6):8–13.
Bajpai P. Treatment of pulp and paper mill effluents with anaerobic
technology. Randalls Road, Leatherhead, UK: Pira International;
2000.
Bajpai P, Bajpai PK. Biological colour removal of pulp and paper
mill wastewaters. J Biotechnol 1994;33:211–20.
Balcioglu AI, Ferhan C. Treatability of kraft pulp bleaching waste-
water by biochemical and photocatalytic oxidation. Water Sci
Technol 1999;40(1):281–8.
Baruah BK. Effect of paper mill effluent on plankton population of
wetland. Environ Ecol 1997;15(4):770–7.
Berube PR, Hall ER. Fate and removal kinetics of contaminants
contained in the evaporator condensate during treatment for
reuse using a high temperature membrane bioreactor. Proc.
86th PAPTAC annual meeting, Montreal, Quebec. Canada: Pulp
and Paper Technical Association of Canada; 2000. p. B67.
Berube PR, Kahmark KA. Pulp and paper mill effluents. Water
Environ Res 2001;73(5):1–36.
Borch-Due A, Anderson R, Opheim B. Treatment of integrated
newsprint mill wastewater in moving bed biofilm reactors. Wa-
ter Sci Technol 1997;35(2–3):173–80.
Bryant CW, Avenell JJ, Barkley WA, Thut RN. The removal of
chlorinated organics from conventional pulp and paper waste-
water treatment systems. Water Sci Technol 1992;26(1–2):
417–25.
Bryant CW, Barkley WA, Garett RM, Gardner FD. Biological ni-
trification of kraft wastewater. Water Sci Technol 1997;35(2–3):
147–53.
Carlson B-L, Ericsson T, Loyblad R, Persson S, Simon O. The
reconstruction of an aerated lagoon to a long-term aerated sludge
(LAS) plant at Sodra cell, Monsteras kraft pulp mill. Tappi
International Environmental Conference and Exhibit, Denver,
CO, vol. 1. Norcross, GA 30092, USA: Technical Association
for Pulp and Paper Industry (TAPPI); 2000. p. 363–71.
Chandra R. Microbial decolourisation of pulp mill effluent in pres-
ence of nitrogen and phosphorous by activated sludge process. J
Environ Biol 2001;22(1):23–7.
Chen W, Horan NJ. The treatment of a high strength pulp and paper
mill effluent for wastewater re-use (II) biological sulphate re-
moval from effluent with a low COD/sulphate ratio. Environ
Technol 1998;19:163–71.
Chernoberezhskii YuM, Dyagileava AS, Barysheva IA. Coagula-
tion treatment of wastewaters from paper and pulp plants. Russ J
Appl Chem 1994;67(3):354–9.
Chernysh A, Liss NS, Allen GD. A batch study of the aerobic and
anaerobic removal of chlorinated organic compounds in an aer-
ated lagoon. Water Pollut Res J Can 1992;27(3):621–38.
Choudhury S, Sahoo N, Manthan M, Rohela RS. Fungal treatment
of pulp and paper mill effluents for pollution control. J Ind
Pollut Control 1998;14(1):1–13.
Dalentoft E, Thulin P. The use of the kaldnes suspended carrier
process in treatment of wastewaters from the forest industry.
Water Sci Technol 1997;35(2–3):123–30.
Das KT, Jain AK. Pollution prevention advances in pulp and paper
processing. Environ Prog 2001;20(1):87–92.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5854
Das CP, Patnaik LN. Removal of lignin by industrial solid wastes.
Pract Period Hazard, Toxic, Radioact Waste Manag 2000;
4(4):156–61.
Demirbas G, Gokcay CF, Dilek FB. Treatment of organic chlorine
in pulping effluents by activated sludge. Water Sci Technol
1999;40(1):275–9.
De Pinho MN, Minhalma M, Rosa MJ, Taborda F. Integration of
flotation/ultrafiltration for treatment of bleached pulp effluent.
Pulp Pap Can 2000;104(4):50–4.
Dey A, Sarkar D, Sengupta B, Banerjee S. Wastewater treatment in
pulp and paper industry-trend and practices. Indian J Environ
Prot 1991;11(12):899–905.
Dilek FB, Gokcay CF. Treatment of effluents from hemp-based
pulp and paper industry: waste characterization and physico-
chemical treatability. Water Sci Technol 1994;29(9):161–3.
D’surney SJ, Eddy LP, Felder DP, Rodgers JH, Deardorff TL.
Assesment of the impact of a bleached kraft mill effluent on a
south-central USA river. Environ Toxicol 2002;15(1):28–39.
Dube M, McLean R, MacLatchy D, Savage P. Reverse osmosis
treatment: effects on effluent quality. Pulp Pap Can 2000;
101(8):42–5.
Dufresne R, Caouette L, Norval GW, Kanters CJ. Treat-
ment of clean condensate using catalytically enhanced oxida-
tion. Proc. 86th PAPTAC annual meeting, Montreal, Quebec.
Canada: Pulp and Paper Technical Association of Canada;
2000. p. A257.
Dufresne R, Liard A, Blum SM.Anaerobic treatment of condensates:
at a kraft pulp and paper mill. Water Environ Res 2001;73(1):
103–9.
Duncan A, Thia B. Treatment of pulp and paper mill effluent. Aust
Biotechnol 1992;2(4):235.
Duran N, Esposito E, Innicentini-Mei LH, Canhos PV. A new al-
ternative process for kraft E1 effluent treatment. Biodegradation
1994;5:13–9.
Dutta SK. Study of the physicochemical properties of effluent of the
paper mill that affected the paddy plants. J Environ Pollut
1999;6(2 and 3):181–8.
Erisction G, Larsson A. DNA A dots in perch (Perca fluviatillis) in
coastal water pollution with bleachen in pulp mill effluents.
Ecotoxicol Environ Saf 2000;46:167–73.
Falth F. Ultrafiltration of E1 stage effluent for partial closure of
the bleach plant. Proc. 86th PAPTAC annual meeting, Mon-
treal, Quebec. Canada: Pulp and Paper Technical Association
of Canada; 2000. p. B85.
Felder DP, D’surney SJ, Rodgers JH, Deardorff TL. A comprehen-
sive environmental assessment of a receiving aquatic system
near an unbleached kraft mill. Ecotoxicology 1998;7:313–24.
Foelkel C. Advanced waste treatment. Pulp Pap 1989;63(4):173–4.
Franta JR, Wilderer PA. Biological treatment of papermill waste-
water by sequencing batch reactor technology to reduce residual
organics. Water Sci Technol 1997;35(1):129–36.
Franta J, Helmreich B, Pribyl M, Adamietz E, Wilderer PA.
Advanced biological treatment of papermill wastewaters; effects
of operating conditions on COD removal and production of sol-
uble organic compounds in activated sludge systems. Water Sci
Technol 1994;30(3):199–207.
Freire RS, Kunz A, Duran N. Some chemical and toxicological
aspects about paper mill effluent treatment with ozone. Environ
Technol 2000;21:717–21.
Ganjidoust H, Tatsumi K, Yamagishi T, Gholian RN. Effect of syn-
thetic and natural coagulant on lignin removal from pulp and
paper waste water. Water Sci Technol 1997;35(2–3):291–6.
Ginkel GCV, Virtapohja J, Steyaert JAG, Alen R. Treatment of
EDTA-containing pulp and paper will wastewaters in activated
sludge plants. Tappi J 1999;82(2):138–42.
Gokcay FC, Dilek FB. Treatment of effluents from hemp-based
pulp and paper industry (2) biological treatability of pulping
effluents. Water Sci Technol 1994;29(9):165–8.
Graves JW, Joyce TW. A critical review of the ability of biological
treatment systems to remove chlorinated organics discharged by
the paper industry. Water SA 1994;20(2):155–60.
Gubelt G, Lumpe C, Joore L. Towards zero liquid effluents at
Niederauer Muhle—the validation of two noval separation tech-
nologies. Pap Technol (UK) 2000;41(8):41–8.
Gune NV. Total water management in pulp and paper industry with
focus on achieving ‘zero effluent discharge’ status. IPPTA J
2000;12(4):137–42.
Gupta A. Pollution load of paper mill effluent and its impact on
biological environment. J Ecotoxicol Environ Monit 1997;7(2):
101–12.
Gupta VK, Minocha AK, Jain N. Batch and continuous studied on
treatment of pulp mill wastewater by aeromonas formicans. J
Chem Technol Biotechnol 2001;76:547–52.
Hansen E, Zadura L, Frankowski S, Wachowicz M. Upgrading of an
activated sludge plant with floating biofilm carriers at Frant-
schach Swiecie S.A. to meet the new demands of year 2000.
Water Science and Technology 1999;40(11–12):207–14.
Hassan MM, Hawkyard CJ. Decolourisation of aqueous dyes by
sequential oxidation treatment with ozone and Fenton’s
reagent. Journal of Chemical Technology and Biotechnology
2002;77:834–41.
Helble A, Schalyer W, Liechti PA, Jenny R, Christian MH. Ad-
vanced effluent treatment in the pulp and paper industry with a
combined process of ozonation and fixed bed biofilm reactors.
Water Sci Technol 1999;40(11–12):343–50.
Hinck ML, Ferguson J, Puhaakka J. Resistance of EDTA and DPTA
to aerobic biodegradation. Water Sci Technol 1997;35(2–3):
25–31.
Holmbom B, Harju L, Lindholm J, Groning AL. Effect of a pulp
and paper mill on metal concentration in the receiving lake
system. Aqua Fenn 1994;24(1):93–110.
Hostachy JC, Lenon G, Pisicchio JL, Coste S, Lgeay C. Reduction
of pulp and paper mill pollution by ozone treatment. Water Sci
Technol 1997;35(2–3):261–8.
Howe J, Michael RW. Effects of pulp mill effluent irrigation on the
distribution of elements in the profile of an arid region soil.
Environ Pollut 1998;105:129–35.
Jackson-Moss CA, Maree JP, Wotton SC. Treatment of bleach plant
effluent with the biological granular activated carbon process.
Water Sci Technol 1992;26(1–2):427–34.
Jahren SJ, Oedegaard H. Treatment of thermomechanical pulping
(TMP) whitewater in termophilic (55 (C) anaerobic–aerobic
moving bed biofilm reactors. Water Sci Technol 1999;40(8):
81–90.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 55
Jahren SJ, Rintala JA, Odegaard H. Evaluation of internal thermo-
philic biotreatment as a strategy in TMP mill closure. Tappi J
1999;82(8):141–9.
Jahren JS, Rintala JA, Odegaard H. Aerobic moving bed biofilm
reactor treating thermomechanical pulping whitewater under
thermophilic conditions. Water Research 2002;36:1067–75.
Jemaa N, Thompson R, Paleologou M, Berry RM. Non-process
elements in the kraft recovery cycle, Part II: control and removal
options. Pulp and Paper Canada 2000;101(2):41–6.
Johnsen K, Tana J, Lehtinen K-J, Stuthridge T, Mattsson K, Hem-
ming J, Carlberg GE. Experimental field exposure of brown
trout to river receiving effluent from an integrated news-
print mill. Ecotoxicology and Environmental Safety 1998;40:
184–93.
Jokela P, Keskitalo P. Plywood mill water system closure by dis-
solved air floatation treatment. Water Science and Technology
1999;40(11–12):33–41.
Jonsson AS, Jonsson C, Teppler M, Tomani P, Wannstrom S. Treat-
ments of paper coating colour effluents by membrane filtration.
Desalination 1996;105:263–76.
Junna J, Ruonala S. Trends and guidelines in water pollution con-
trol in the Finnish pulp and paper industry. Tappi J 1991;
74(7):105–11.
Kabdash I, Tunay O, Eldem N. Treatability of wastepaper pulping
process wastewater. Proceedings of the Industrial Waste Confer-
ence, West Lefayette, USA, vol. 51. Chelsea, Michigan 68118,
USA: Ann Arbor Press Inc.; 1996. p. 645–50.
Kahmark KA, Unwin JP. Pulp and paper effluent management.
Water Environ Res 1996;68(4):551.
Kahmark KA, Unwin JP. Pulp and paper effluent management.
Water Environ Res 1998;70(4):667.
Kahmark KA, Unwin JP. Pulp and paper effluent management.
Water Environ Res 1999;71(5):836.
Kallas J, Munter R. Post-treatement of pulp and paper industry
wastewaters using oxidation and adsorption processes. Water
Sci Technol 1994;29(5–6):259–71.
Kantardjieff A, Jones JP. Practical experiences with aerobic biofil-
ters in TMP sulfite and fine paper mills in Canada. Water Sci
Technol 1997;35(2–3):227–34.
Kennedy KJ, Graham B, Droste RL, Fernandes L, Narbaitz R.
Microtox and Ceriodaphnia dubia toxicity of BKME with
powdered activated carbon treatment. Water SA 2000;26(2):
205–16.
King HM, Baldwin DS, Rees GN, Mcdonald S. Apparent bio-
accumulation of Mn derived from paper-mill effluent by the
freshwater crayfish cherax destructor—the role of Mn oxidis-
ing bacteria. Sci Total Environ 1999;226:261–7.
Knudsen L, Pedersen JA, Munck J. Advanced treatment of paper
mill effluents by a two-stage activated sludge process. Water Sci
Technol 1994;30(3):173–81.
Korhonen S, Tuhkanen T. Effects of ozone on resin acids in ther-
momechanical pulp and paper mill circulation waters. Ozone:
Sci Eng 2000;22(6):575–84.
Korhonen SM, Metsarinne SE, Tuhakanen TA. Removal of eth-
ylenediaminenetraacetic acid (EDTA) from pulp mill effluents
by ozonation. Ozone: Sci Eng 2000;22:279–86.
Kovacs TG, Martel PH, Voss RH. Assessing the biological status of
fish in a river receiving pulp and paper mill effluents. Environ
Pollut 2002;118:123–40.
Laari A, Korhonen S, Tuhkanen T, Verenich S, Kallas J. Ozonation
and wet oxidation in the treatment of thermomechanical pulp
(TMP) circulation waters. Water Sci Technol 1999;40(11–12):
51–8.
Laari A, Korhonen S, Kallas J, Tuhkanen T. Selective removal of
lipophilic wood extractives from paper mill water circulations
by ozonation. Ozone: Sci Eng 2000;22:585–605.
Larisch BC, Duff JB. Effect of H2 O2 and data on the character-
istics and treatment of TCF (totally chlorine-free) and ECF
(elementally chlorine-free) kraft pulping effluents. Water Sci
Technol 1997;35(2–3):163–71.
Larisch BC, Duff JB. Effect of DTPA and EDTA on activated
sludge reactors treating bleached kraft mill effluent. Tappi J
2000;83(6):54.
Leppanen H, Oikari A. Occurrence of retene and resin acids in
sediments and fish bile from lake receiving pulp and a
paper mill effluents. Environ Toxicol Chem 1999;18(7):
1498–505.
Lescot JC, Jappinen H. Effluent treatment in pulp and paper mills:
present technology and development trends. Appita J 1994;
47(4):330–2.
Lindstrom-Seppa P, Hunskonen S, Kotelevtsev S, Mikkelson P, Ran-
nen T, Stepanova L, et al. Toxicity and mutagenity of waste
waters from Baikalsk pulp and paper mill: evaluation of pollutant
contamination in lake Baikal. Mar Environ Res 1998;46(1–5):
273–7.
Magnus E, Carlberg GE, Norske HH. TMP wastewater treatment
including a biological high-efficiency compact reactor. Nord
Pulp Pap Res J 2000a;15(1):29–36.
Magnus E, Carlberg GE, Norske HH. TMP wastewater treatment
including a biological high-efficiency compact reactor. Nord
Pulp Pap Res J 2000b;5(1):37–45.
Magnus E, Hoel H, Carlberg GE. Treatment of an NSSC effluent in
a biological high-efficiency compact reactor. Tappi J 2000c;
83(1):149–56.
Makris SP, Banerjee S. Fate of resin acids in pulp mills secondary
treatment systems. Water Res 2002;36:2878–82.
Malmquist A, Ternstrom A, Welander T. In-mill biological treat-
ment for paper mill closure. Water Sci Technol 1999;40(11–12):
43–50.
Mandal TN, Bandana TN. Studies on physicochemical and
biological characteristics of pulp and paper mill effluents
and its impact on human beings. J Freshw Biol
1996;8(4):191–6.
Mendonca R, Guerra A, Ferraz A. Delignification of Pinus teada
wood chips treated with ceriporiopsis sbvermispora for prepar-
ing high-yield kraft pulp. J Chem Technol Biotechnol 2002;
77:411–8.
Merrill DT, Maltby CV, Kahmark K, Gerhardt M, Melecer H. Eval-
uating treatment process to reduce metals concentrations in pulp
and paper mill wastewaters to extremely low values. Tappi J
2001;84(4):52.
Milet GM, Duff SJB. Treatment of kraft condensates in a feedback -
controlled sequencing batch reactor. Water Sci Technol 1998;
38(4–5):263–71.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5856
Mobius CH, Cordes-Tolle M. Advanced treatment of paper mill
wastewaters. Water Sci Technol 1994;29(5–6):273–82.
Mohamed M, Matayun M, Lim TS. Chlorinated organics in tropical
hardwood kraft pulp and paper mill effluents and their elimina-
tion in an activated sludge treatment system. Pertanika 1989;
2(3):387–94.
Murthy BSA, Sihorwala TA, Tilwankar HV, Killedar DJ. Remov-
al of colour from pulp and paper mill effluents by sorption
techn ique—a case s tudy. Ind ian J Env i ron Pro t
1991;11(5):360.
Nakamura Y, Sawada T, Kobayshi F, Godliving M. Microbial treat-
ment of kraft pulp wastewater pretreated with ozone. Water Sci
Technol 1997;35(2–3):277–82.
Narbaitz RM, Droste RL, Fernandes L, Kennedy KJ, Ball D.
PACTk process for treatment of kraft mill effluent. Water Sci
Technol 1997;35(2–3):283–90.
Nemerow NL, Dasgupta A. Industrial and hazardous waste man-
agement. New York: Van Nostrand Reinhold; 1991.
Norris P, Marshall R, Richard M. High temperature on activated
sludge treatment performance and sludge quality in a recycle
mill. Tappi International Environmental Conference and Ex-
hibit, Denver, CO, vol. 1. Norcross, GA, 30092, USA: Tech-
nical Association for Pulp and Paper Industry (TAPPI); 2000.
p. 383–7.
O’connor B, Kovacs T, Gibbons S, Strang AL. Carbon dioxide in
pulp and paper mill effluents from oxygen -activated sludge
treatment plants as a potential source of distress and toxicity
to fish. Water Qual Res J Can 2000;35(2):189–200.
Oeller HJ, Daniel I, Weinberger G. Reduction in residual COD in
biologically treated paper mill effluents by means of combined
Ozone and Ozone/UV reactor stages. Water Sci Technol 1997;
35(2–3):269–76.
Owens JW, Swanson SM, Birkholz DA. Environmental monitoring
of bleached kraft pulp mill chlorophenolic compounds in a
Northern Canadian River system. Chemosphere 1994;29(1):
89–109.
Peerbhoi Z. Treatability studies of black liquor by UASBR-PhD
thesis 2000. University of Roorkee, India.
Perez M, Romero LI, Sales D. Comparative performance of high
rate anaerobic thermophilic technologies treating industrial
wastewater. Water Res 1998;2(3):559–64.
Perez M, Torrades F, Domenech X, Peral J. Removal of organic
contaminants in pulp effluents by AOPs: an economic study.
J Chem Technol Biotechnol 2002a;77:525–32.
Perez M, Torrades F, Garcia-Hortal JA, Domenech X, Peral J. Re-
moval of organic contaminants in paper pulp treatment effluents
under fenton and photo-fenton conditions. Appl Catal 2002b;
36(1):63–74.
Perez M, Torrades F, Domenech X, Peral J. Treatment of bleach-
ing Kraft mill effluents and polychlorinated phenolic com-
pounds with ozonation. J Chem Technol Biotechnol 2002c;77:
891–7.
Poggi-Varaldo HM, Estrada-Vazquez C, Fernandez-Villagomez G,
Esparza-Garcia F. Pretreatment of black liquor spills effluent.
Proceedings of the Industrial Waste Conference, West Lafayette,
USA 1996;51:651–61.
Prasad GK, Gupta RK. Decolourization of pulp and paper mill
effluent by two White-rot fungi. Indian J Environ Health 1997;
39(2):89–96.
Raghuveer S, Sastry CA. Effect of simple in-plant control measures
on the characteristics of wastewater from a pulp and paper mill.
Indian J Environ Prot 1990;10(10):739–46.
Raghuveer S, Sastry CA. Biological treatment of pulp mill waste-
water and study of biokinetic constants. Indian J Environ Prot
1991;11(8):614–21.
Rajeshwari KV, Balakrishnan M, Kansal A, Lata K, Kishore VVN.
State of the art of anaerobic digestion technology for industrial
wastewater treatment. Renew Sustain Energy Rev 2000;4(2):
135–56.
Rajvaidya N, Markandey DK. Advances in environmental science
and technology: treatment of pulp and paper industrial effluent.
Ansari Road, New Delhi, India: A.P.H. Publishing; 1998.
Reid TK, Simon A. Feasibility study of sequencing batch reactor
technology treating high strength foul condensate for methanol
reduction. Tappi International Environmental Conference and
Exhibit, Denver, CO 2000;1:185–91.
Reilama I, Ilomaki N. Respect for the environment is part of com-
petitiveness-best available technology applied to an old pulp
mill at Kastinen. Water Sci Technol 1999;40(11–12):201–6.
Rintala JA, Puhakka JA. Anaerobic treatment in pulp and paper mill
waste management: a review. Bioresour Technol 1994;47:1–18.
Rohella RS, Choudhury S, Manthan M, Murthy JS. Removal of
colour and turbidity in pulp and paper mill effluents using poly-
electrolytes. Indian J Environ Health 2001;43(4):159–63.
Rovel JM, Trudel JP, Lavalle P, Schroeter I. Paper mill efflu-
ent treatment using biofliltration. Water Sci Technol 1994;
29(10–11):217–22.
Roy-Arcand L, Archibald FS. Ozonation as a treatment for mechan-
ical and chemical pulp mill effluents. Ozone: Sci Eng
1996;18:363–84.
Rudolfs W, Amberg HR. White water treatment: V. Areation with
nonflocclent growths. Sew Ind Wastes 1953;25(1):70–8.
Rusten B, Mattsson E, Due BA, Westren T. Treatment of pulp and
paper industry wastewaters in novel moving bed biofilm reac-
tors. Water Sci Technol 1994;30(3):161–71.
Sakurai A, Yamomoto T, Makabe A, Kinoshita S, Sakakibara M.
Removal of lignin in a liquid system by an isolated fungus. J
Chem Technol Biotechnol 2001;77:9–14.
Sandquist KK, Sandstrom E. A novel technology to treat foul con-
densate and NCG gases in a closed loop. TAPPI International
Environmental Conference and Exhibit, Denver, CO, vol. 1.
Norcross, GA, 30092, USA: Technical Association for Pulp
and Paper Industry (TAPPI); 2000. p. 147–55.
Saunamaki R. Activated sludge plants in Finland. Water Sci Tech-
nol 1997;35(2–3):235–43.
Saxena N, Gupta RK. Decolourization and delignification of pulp
and paper mill effluent by white rot fungi. Indian J Exp Biol
1998;36:1049–51.
Schmidt T, Lange S. Treatment of paper mill effluent by the
use of ozone and biological systems: large scale application
at lang paper, Ettringen (Germany). Tappi International Envi-
ronmental Conference and Exhibit, Denver, CO, vol. 2. Nor-
cross, GA, 30092, USA: Technical Association for Pulp and
Paper Industry (TAPPI); 2000. p. 765–75.
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–58 57
Schnell A, Hall ER, Skog S. Anaerobic and aerobic treatability of
high-yield sulphate spent liquor. Water Pollut Res J Can
1992;27(3):601–20.
Schnell A, Sabourin MJ, Skog S, Garvie M. Chemical character-
ization and biotreability of effluents from an integrated alkaline-
peroxide mechanical pulping/machine finish coated paper mill.
Water Sci Technol 1997;35(2–3):7–14.
Schnell A, Steel P, Melcer H, Hodson PV, Carey JH. Enhanced
biological treatment of bleached kraft mill effluents: I. Removal
of chlorinated organic compounds and toxicity. Water Res
2000a;34(2):493–500.
Schnell A, Steel P, Melcer H, Hodson PV, Carey JH. Enhanced
biological treatment of bleached kraft mill effluents: II. Reduc-
tion of mixed function oxygenase (MFO) induction in fish.
Water Res 2000b;34(2):501–9.
Sevimli MF, Sarikaya HZ. Ozone treatment of textile effluents and
dyes: effect of applied ozone dose, pH and dye concentration. J
Chem Technol Biotechnol 2002;77:842–50.
Shaw CB, Carliell CM, Wheatley AD. Anaerobic/aerobic treatment
of coloured textile effluents using sequencing batch reactors.
Water Res 2002;36:1993–2001.
Shawwa AR, Smith DW, Sego DC. Color and chlorinated organics
removal from pulp wastewater using activated petroleum coke.
Water Res 2001;35(3):745–9.
Sheela V, Distidar MG. Treatment of black liquor wastes from small
paper mills. Indian J Environ Prot 1989;9(9):661–6.
Shere SM, Daly PG. High rate biological treatment of TMP efflu-
ent. Pulp Pap Can 1982;83n:61–6.Sinclair WF. Controlling pollution from Canadian pulp and paper
manufactures: a federal perspective. Ottawa: Canadian Govern-
ment Publishing Centre; 1990.
Singh RS, Marwaha S.S, Khanna PK. Characteristics of pulp and
paper mill effluents. J Ind Pollut Control 1996;12(2):163–72.
Skipperud L, Salbu B, Hagebo E. Speciation of trace elements in
discharges from the pulp industry. Sci Total Environ 1998;
217:251–6.
Smook GA. Handbook for pulp and paper technologist. Vancouver,
Bellingham: Angus Wilde Publications; 1992.
Springer AM. Industrial environmental control: pulp and paper
industry. Atlanta, Georgia: TAPPI Press; 2000.
Srinivasan D, Unwin JP. Pulp and paper effluent management.
Water Environ Res 1995;67(4):531.
Srivastava SK, Bembi R, Singh AK, Sharma A. Physicochemical
studies on the characteristics and disposal problems of small and
large pulp and paper mill effluents. Indian J Environ Prot 1990;
10(6):438–42.
Stepanova L, Lindstrom-Seppa P, Hanninen OOP, Kotelevtsev SV,
Glaser VM, Novikow CN, et al. Lake Baikal: biomonitoring of
pulp and paper mill wastewater. Aquat Ecosyst Health Manag
2000;3:259–69.
Stuthridge TR, Mcfarlane PN. Adsorbable organic halide removal
mechanisms in a pulp and paper mill aerated lagoon treatment
system. Water Sci Technol 1994;29(5–6):195–208.
Stuthridge TR, Campin DN, Langdon AG, Mackie KL, Mcfarlange
PN, Wikins AL. Treatability of bleached kraft pulp and paper
mill wastewaters in a New Zealand aerated lagoon treatment
system. Water Sci Technol 1991;24(3/4):309–17.
Sullivan, E.C., 1986. The use of advanced treatment methods for
removal of color and dissolved solids from pulp and paper
wastewater-Master’s thesis. Virginia Polytechnic Institute and
State University.
TAPPI. Environmental issues: a TAPPI press anthology of pub-
lished papers. Atlanta, GA: TAPPI Press; 1990.
Tardif O, Hall ER. Alternatives for treating recirculated newsprint
whitewater at high temperatures. Water Sci Technol 1997;
35(2–3):57–65.
Taseli B, Gokcay CF. Biological treatment of paper pulping efflu-
ents by using a fungal reactor. Water Sci Technol 1999;
40(11–12):93–9.
Thompson G, Swain J, Kay M, Forster CF. The treatment of pulp
and paper mill effluent: a review. Bioresour Technol 2001;
77(3):275–86.
Tong Z, Wada S, Takao Y, Yamagishi T, Hiroyasu I, Tamatsu K, et
al. Treatment of bleaching wastewater from pulp-paper plants in
China using enzymes and coagulants. J Environ Sci 1999;
11(4):480–4.
Torrades F, Peral J, Perez M, Domenech X, Hortal JAG, Riva MC.
Removal of organic contaminants in bleached kraft effluents
using heterogeneous photocatalysis and ozone. Tappi J 2001;
84(6):63.
Trotter PC. Biotechnology in the pulp and paper industry: a review-
vol. (II). Tappi J 1990a;73(5):201–5.
Trotter PC. Biotechnology in the pulp and paper industry: a review-
vol (I). Tappi J 1990b;73(4):198–204.
US EPA. EPA office of compliance sector notebook project: profile
of pulp and paper industry. Washington, DC 20460, USA: EPA/
310-R-95-015; 1995.
US EPA. Permit guidance document: pulp, paper and paperboard
manufacturing point source category. EPA-821-B-00-003; 2000.
Vass KK, Mukopadhyay MK, Mistra K, Joshi HC. Respiratory
stresses in fishes exposed to paper and pulp wastewater. Environ
Ecol 1996;14(4):895–7.
Verenich S, Kallas J. Coagulation as a post-treatment for wet oxi-
dation of pulp and paper mill circulation waters. Chem Eng
Technol 2001;24(11):1183–8.
Verenich S, Laari A, Kallas J. Wet oxidation of concentrated waste-
water of paper mills for water cycle closing. Waste Manage
(N.Y.) 2000;20(4):287–93.
Verenich S, Laari A, Kallas J. Combination of coagulation and
catalytic wet oxidation for the treatment of pulp and paper mill
effluents. Water Sci Technol 2001;44(5):145–52.
Vlyssides AG, Economides DG. Characterization of wastes from a
newspaper wash deinking process. Fresenius Environ Bull 1997;
6:734–9.
Wagner M, Nicell JA. Treatment of a foul condensate from kraft
pulping with horseradish peroxidase and hydrogen peroxide.
Water Sci Technol 2001;35(2):485–95.
Wang I-C, Pan T-T. Interference of some papermaking chemical
additives in the coagulation of wastewater. Taiwan J For Sci
1999;14(4):367–84.
Wang X, Mize TH, Saunders FM, Baker SA. Biotreatability test of
bleach wastewaters from pulp and paper mills. Water Sci Tech-
nol 1997;35(2–3):101–8.
Wayland M, Trudeau S, Marchant T, Parker D, Hobson KA. The
D. Pokhrel, T. Viraraghavan / Science of the Total Environment 333 (2004) 37–5858
effect of pulp and paper mill effluent on an insectivorous bird,
the tree Swallow. Ecotoxicology 1998;7:237–51.
Webb LJ. Integrated pollution control of emissions from the pulp
and paper industry. Water Sci Technol 1994;29(5–6):123–30.
Welander T, Lofqvist A, Selmer A. Upgrading aerated lagoons
at pulp and paper mills. Water Sci Technol 1997;35(2–3):
117–22.
Welander T, Ericsson T, Gunnarsson L, Storlie A. Reduction sludge
production in biological effluent treatment by applying the LSP
process. Tappi International Environmental Conference and Ex-
hibit, vol. 2. 2000. p. 757–63.
Wenta B, Hartmen B. Dissolved air flotation system improves
wastewater treatment at Glatfelter. Pulp Pap 2002;76(3):43–7.
Yamamoto S. Ozone treatment of bleached kraft pulp and waste
paper. Japan Tappi J 2001;55(4):90–7.
Yeber MC, Rodriquez J, Freer J, Baeza J, Duran N, Mansilla HD.
Advanced oxidation of a pulp mill bleaching wastewater. Che-
mosphere 1999;39(10):1679–88.
Yen NT, Oanh NTK, Reutergard LB, Wise DL, Lan LTT. An inte-
grated waste survey and environmental effects of COGIDO, a
bleached pulp and paper mill in Vietnam on the receiving water
body. Global Environ Biotechnol 1996;66:349–64.
Zaidi A, Buisson H, Sourirajan S, Wood H. Ultra-and nano-filtra-
tion in advanced effluent treatment schemes for pollution con-
trol in the pulp and paper industry. Water Sci Technol 1992;
25(10):263–76.
Zamora PP, Esposito E, Pelegrini R, Groto R, Duran N. Effluent
treatment of pulp and paper, and textile industries using
immobilised horseradish peroxidase. Environ Technol 1998;
19:55–63.
Zhang X, Stebbing D, Soong J, Saddler JN. The Removal of det-
rimental dissolved and colloidal substances by a combined fun-
gal and enzyme treatment system. 86th Annual Meeting,
Montreal, Quebec, Canada; Pulp and Paper Technical Associa-
tion of Canada; 2000a. p. B99–B102.
Zhang X, Stebbing DW, Saddler JN. Enzyme treatment of the dis-
solved and colloidal substances present in mill white water and
the effects of the resulting paper properties. J Wood Chem
Technol 2000b;20(3):321–35.
Zhou H, Smith DW. Process parameter development for ozonation
of kraft pulp mill effluents. Water Sci Technol 1997;35(2–3):
251–9.