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. 
RAZISKAVE IN RAZVOJ
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RAZISKAVE IN RAZVOJ RAZISKAVE IN RAZVOJ
Identificiranje pomembnih vsebin
Prvi korak interpretacije življenjskega 
cikla vključuje pregled informacij iz prvih 
treh faz LCA, da bi identificirali podatke, 
ki najbolj vplivajo na potek LCI in LCIA 
pri vsakem izdelku, procesu oziroma 
storitvi. S pomočjo pridobljenih ugotovitev 
določamo popolnost, skladnost in 
natančnost študije. Pred določanjem, 
kateri del LCI in LCIA ima največji vpliv na 
rezultate posamezne alternative, moramo 
podrobno pregledati prejšnje faze študije. 
Nato pregledamo zbrane informacije in 
predstavitev rezultatov, da ugotovimo, ali 
je bil uresničen cilj in namen študije. Če 
je uresničen, nadaljujemo z interpretacijo 
rezultatov. Določanje pomembnejših 
vsebin je v nekaterih primerih 
komplicirano opravilo. Kot pripomoček 
za identificiranje pomembnih podatkov 
in določanje njihovega pomena lahko 
uporabimo naslednje metode:
 ocena vpliva (prispevke posameznih 
faz življenjskega cikla primerjamo s 
celotnim rezultatom);
 ocena dominantnosti (statistična 
orodja ali druga pomagala, kot 
so kvantitativno ali kvalitativno 
rangiranje, uporabljamo za 
identificiranje pomembnih 
elementov prispevanja);
 ocenjevanje anomalij (nenavadna 
ali presenetljiva odstopanja od 
pričakovanih ali normalnih rezultatov 
moramo natančno preučiti).
Pomembne vsebine so sestavljene iz:
 parametrov inventarja (so poraba 
energije, emisije, odpadki …);
 kazalnikov kategorij vplivov (izraba 
virov surovin, emisije, odpadki …);
 bistvenih prispevkov k LCI ali LCIA 
rezultatom (posamezne procesne 
enote ali skupine procesov, kot so 
transport, pridelava energije …).
Ocenitev popolnosti, natančnosti in 
skladnosti podatkov
Da bi zagotovili popolnost, natančnost in 
skladnost podatkov, moramo opraviti:
 kontrolo popolnosti (ugotavljanje 
popolnosti študije);
 kontrolo natančnosti (ocenjevanje 
natančnosti pomembnih podatkov, ki 
imajo velik vpliv na rezultate);
 kontrolo skladnosti (ocenjevanje 
skladnosti pri sprejemanju omejitev 
in predpostavk, zbiranju podatkov 
in dodeljevanju vplivov kategorijam 
vplivov za vsako alternativo posebej).
Sprejemanje sklepov in priporočil
Cilj tega koraka je interpretacija 
rezultatov za določevanje izdelkov 
oziroma storitev, ki imajo najugodnejši 
vpliv na okolje. Pomembno je, da sprejeti 
sklepi in priporočila temeljijo le na 
utemeljenih dejstvih. Prav tako je zelo 
pomembno razumevanje in poročanje 
o morebitnih negotovostih rezultatov. 
V nekaterih primerih je prav zaradi 
negotovosti in omejitev izbrane metode, 
ki je bila uporabljena za LCA, napoved 
najustreznejšega izdelka oziroma storitve 
nejasna. V takšnem primeru so rezultati 
analize še vedno koristni. Uporabljamo 
jih za boljše razumevanje vpliva na 
naravo in posledično na človekovo 
zdravje, za razumevanje posameznih 
vplivov ter za ugotavljanje obsega 
posameznih vplivov glede na primerjane 
izdelke oziroma storitve.
2.5 Poročanje rezultatov
Ko je LCA študija končana, je potrebno 
iz zbranega gradiva pripraviti poročilo o 
poteku študije. Poročilo mora na jasen in 
urejen način predstaviti rezultate, podatke, 
metode, omejitve in predpostavke.
3 Zaključki
LCA postaja eno od najbolj zanimivih orodij 
za presojo vplivov na okolje. Zelo pogosta 
je uporaba ISO 14040 in ISO 14044 
standardov, kot smernic za izdelavo LCA 
študije, kar povečuje primerljivost ocen in 
pridobljenih rezultatov.
Podjetja se čedalje pogosteje odločajo 
za izdelavo LCA študije, saj jim poleg 
vpliva proizvodnje izdelkov na okolje 
rezultati prikažejo tudi procese oziroma 
dele procesov, ki so ekonomsko 
najpotratnejši. Tako lahko podjetja 
prilagodijo svoje procese, da postanejo 
ekonomsko ugodnejši.
Pri LCA študijah v papirnih industrijah, kjer 
so študije predpostavljale, da so papirni 
izdelki samo za enkratno uporabo, plastični 
pa za večkratno, je večina rezultatov 
pokazala na večje obremenjevanje okolja 
pri papirnih izdelkih. Vendar vemo, da temu 
ni tako. Papirni izdelki so še vedno okolju 
prijaznejši kot nekateri konkurenčni izdelki.
Slika 2: Uporabljaj papir! [9]
Figure 2: Use paper! [9]
4 LITERATURA IN VIRI
[1] HUNT, R. G. in FRANKLIN, W. E. LCA – 
How it Came About. Personal reflections on 
the Origin and the Development of LCA in 
the USA. International Journal of Life Cycle 
assessment, 1996, 1, 1, str. 4–7.
[2] ISO 14040:2006. Environmental 
management – Life cycle assessment – 
Principles and framework. International 
Organization for Standardization: Geneva, 
Switzerland, 2006.
[3] ISO 14044:2006. Environmental 
management – Life cycle assessment – 
Requirements and guidelines. International 
Organization for Standardization: Ženeva, 
Švica, 2006.
[4] ONGMONGKOLKUL, A., NIELSEN, P . H. 
in NAZDAD, M. M. Life cycle assessment of 
paperboard packaging produced in Thailand, 
Thailand, School of Environment, Resource and 
Development, Asian Institute of Technology, 
2001
[5] DIAS, A. C., ARROJA, L. in CAPELA, I. Life 
Cycle Assessment of printing and writing paper 
produced in Portugal. International Journal 
of Life Cycle Assessment, 2007, 12, 7, str. 
521–528.
[6] IOSIP , A., DOBON, A., HORTAL, M. in 
BOBU, E. The influence of contaminants in the 
environmental impact of recovered paper: a 
life cycle assessment perspective. International 
Journal of Life Cycle Assessment, 2012, 17, 8, 
str. 1050–1058.
[7] GEMECHU, E. D., BUTNAR, I., GOMÀ-
CAMPS, J., PONS, A. in CASTELLS, F. A 
comparison of the GHG emissions caused by 
manufacturing tissue paper from virgin pulp 
or recycled waste paper. International Journal 
of Life Cycle Assessment, 2013, 18, 8, str. 
1618–1628.
[8] Von FALKENSTEIN, E., WELLENREUTER, F. IN 
DETZEL, A. LCA studies comparing beverage 
cartons and alternative packaging: can overall 
conclusions be drawn. International Journal 
of Life Cycle Assessment, 2010, 15, 9, str. 
938–945.
[9] Dostopno na spletu: http://dsmpb.com/
News.html.
1
 dr., Inštitut za celulozo in papir, Ljubljana
(E-pošta: damjan.balabanic@icp-lj.si)
POSSIBILITY OF MUNICIPAL 
WASTEWATER RE-USE IN PAPER 
INDUSTRY
MOŽNOST PONOVNE UPORABE KOMUNALNE 
ODPADNE VODE V PAPIRNI INDUSTRIJI
Aleksandra KRIVOGRAD KLEMENČIČ
1,2
, Klara JARNI
1
, Svenja BIERBAUM
3
1 Introduction
Pulp and paper industry is one of the 
most water-dependent industries [1]. In 
regions with water scarcity there is not 
enough fresh water available to all water 
consumers during dry periods [2]. Paper 
production, which requires large amounts 
of water, is particularly endangered if 
the water supply cannot be maintained 
or the use of freshwater is no longer 
permitted by the authorities [3].
Recently there has been an increase of 
attention in municipal wastewater as an 
alternative source of water for various 
purposes thanks to many advantages 
such as broad availability, relatively stable 
production and effluent quality. Several 
recommendations and an evaluation 
ABSTRACT
As water scarcity is becoming a growing problem in many regions, searching for alternative water sources is of great importance, 
especially for high water consuming industries like paper industry. Municipal wastewater has the advantage of being broadly 
available and relatively stable in production and effluent quality, although microbiological safety can be a problem. Within 
the study presented the possibility of re-use of municipal wastewater treated with advanced oxidation processes (AOPs) in the 
production process of paper industry is shown. Raw municipal wastewater was treated at a lab-scale AOP-treatment plant 
with different AOPs and their combinations. The following AOP treatments were applied: (a) ozone (O
3
); (b) O
3
 + ultraviolet 
irradiation (UV); (c) hydrogen peroxide (H
2
O
2
) and (d) H
2
O
2
 + UV. The most effective option for colour and COD removal was 
the combination of O
3
 and UV, while significant disinfection of municipal wastewater was achieved with all four tested AOPs. 
Municipal wastewater treated with the most efficient AOP combination was used for paper production. The results of the sheet 
former trials showed that use of AOP-treated municipal wastewater for paper production did not impair colour and strength 
properties of paper produced. Thus, municipal wastewater could be successfully re-used in paper industry.
Keywords: advanced oxidation processes, municipal wastewater treatment, ozonation, paper industry, wastewater re-use.
IZVLEČEK
Ker pomanjkanje vode postaja čedalje večji problem v številnih regijah, je iskanje alternativnih virov vode zelo pomembno, še 
posebej za industrijske panoge z visoko porabo vode, kot je papirna industrija. Komunalna odpadna voda ima to prednost, 
da je lahko dostopna, ima relativno stabilno proizvodnjo in kakovost iztoka, vendar pa je problem lahko njena mikrobiološka 
oporečnost. V predstavljeni raziskavi je prikazana možnost ponovne uporabe komunalne odpadne vode, očiščene z naprednimi 
oksidacijskimi postopki (AOPs), v proizvodnem procesu papirne industrije. Surovo komunalno odpadno vodo smo očistili 
na laboratorijski AOP čistilni napravi z različnimi AOP postopki in njihovimi kombinacijami. Uporabili smo naslednje AOP 
kombinacije: (a) ozon (O
3
); (b) O
3
 + ultravijolično sevanje (UV); (c) vodikov peroksid (H
2
O
2
) in (d) H
2
O
2
 + UV. Najbolj učinkovita 
pri odstranitvi barve in KPK je bila kombinacija O
3
 in UV, medtem ko smo znatno dezinfekcijo komunalne odpadne vode dosegli 
z vsemi štirimi testiranimi AOP postopki. Komunalno odpadno vodo, očiščeno z najbolj učinkovito AOP kombinacijo, smo nato 
uporabili za proizvodnjo papirja. Rezultati laboratorijskih poskusov izdelave papirja so pokazali, da uporaba AOP očiščene 
komunalne odpadne vode ni vplivala na barvnometrične in mehanske lastnosti izdelanega papirja. Tako lahko komunalno 
odpadno vodo uspešno ponovno uporabimo v papirni industriji.
Ključne besede: napredni oksidacijski postopki, čiščenje komunalne odpadne vode, ozoniranje, papirna industrija, ponovna 
uporaba odpadne vode.
of potentials of cascading water use 
to substitute fresh water are available 
[4-6]. However, the use of treated 
municipal wastewater brings problems 
(potential health risks due to insufficient 
disinfection, conveying treated 
wastewater to points of consumption) 
that have to be dealt with. Currently, 
the effluents from municipal wastewater 
treatment plants are not generally used 
as a source of reclaimed water. This is 
due to: lack of regulation and legislation 
specifying the conditions for re-uses 
and quality requirements on re-used 
wastewater, together with the motivation 
for wastewater re-use, high costs of 
producing reclaimed water with adequate 
quality and a lack of information about 
the technologies and associated risks 
mentioned above. However, there are 
few cases of municipal wastewater reuse 
in industry, it is mainly used for cooling 
and floor cleaning. In paper industry, 
there are some examples of the cascading 
use of treated municipal wastewater [7]. 
Since June 2012, Holmen Paper from 
Madrid has been replacing fresh water 
for production processes with treated 
municipal wastewater (ultrafiltration + 
reverse osmosis + UV). A level of 30% 
fresh water substitution has been reached 
with target use of 100% reclaimed 
water of the total water consumption 
[8, 9] . Other mills across Europe are also 
discussing this issue.
The main objective of this study is 
to show the possibility of municipal 
wastewater re-use in the production 
processes of paper industry. Raw 

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2
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RAZISKAVE IN RAZVOJ
3.2 AOP experiments
The most efficient combination for colour 
removal (Fig. 2) was O
3
 + UV (86%). The 
second best was O
3
 alone (76%−77%). 
The least effective for colour removal 
was the combination of H
2
O
2
 + UV 
(31%−33%). By comparing O
3
 and O
3
 
+ UV treatments, it can be seen that UV 
light contributed to better decolouration, 
which however did not apply to the H
2
O
2
 
and H
2
O
2
 + UV treatments.
RAZISKAVE IN RAZVOJ
municipal wastewater was treated 
with different advanced oxidation 
processes (AOPs) such as ozone (O
3
); O
3
 
+ ultraviolet irradiation (UV); hydrogen 
peroxide (H2O2) and H
2
O
2
 + UV. 
Municipal wastewater treated with the 
most efficient AOP combination was used 
for paper production.
2 Materials and methods
As a source of wastewater, raw municipal 
wastewater was used, collected from 
a sequencing batch bioreactor (SBR) 
located in the front of the Faculty of 
Civil and Geodetic Engineering of the 
University of Ljubljana in which a part 
of the municipal wastewater of city 
Ljubljana is treated. Prior to the trials, 
wastewater was filtered with black 
ribbon filters (Sartorius-stedim, Grade 
388, 10−15 µm, basis weight 84 g/m
2
) 
to remove solid compounds. Filtered 
wastewater was treated with different 
combinations of AOPs: O
3
; O
3
 + UV; 
H
2
O
2
 and H
2
O
2
 + UV at a lab-scale AOP-
treatment plant (Fig. 1) operating in 
batch mode.
2.1 Pilot plant design
The lab-scale AOP-treatment plant (Fig. 
1) consisted from a plastic wastewater 
tank, a water pump (Iwaki Magnet 
Pump, Iwaki co. LTD), an air pump 
(KNF Neuberger), an air dryer module 
(Lufttrockner module LTM 110-60, 
AquaCare), an O
3
 generator (BasiTech 
III, AquaCare, 500 mg/h), an O
3
 reactor 
(Ozonreaktor OZR 75, AquaCare), an O
3
 
analyser (BMT 964 C, BMT Messetechnik), 
a rotameter (GEMÜ 55/21/14), a benchtop 
meter (multi-parameter analyser C3040, 
Consort) and a UV lamp (Sterilight copper, 
Viqua, 12 W). For a detailed description 
of the lab-scale AOP-treatment plant 
see Krivograd Klemenčič et al. [13]. The 
system was operating in a batch mode 
with a flow rate of the water stream 60 
L/h maintained with the rotameter, but 
the residence time was increased with 
the wastewater returning back to the 
beginning of the system. Consequently 
the system was operating in a batch mode 
with the water being completely mixed.
2.2 Chemical analyses
The following parameters of raw municipal 
wastewater were analysed: pH, electric 
conductivity (EC), colour at 436 nm, 525 
nm and 620 nm, chemical oxygen demand 
(COD), biochemical oxygen demand 
in 5 days (BOD
5
) and total suspended 
solids (TSS). pH and EC were measured 
with the HACH HQ40d Multimeter, 
colour was measured with a portable 
spectrophotometer (Hach DR 2800), COD 
was analyzed according to ISO 6060, BOD
5
 
according to SIST EN 1899-2 and TSS 
according to SIST ISO 11923.
During the AOP experiments, 10 mL of 
sample was taken from the circulation 
loop in the batch system at regular time 
intervals of 40 minutes (10 cycles) for 
COD and colour measurements at 436 
nm, 525 nm and 620 nm. For each 
experiment, 7 samples were taken. 
Before each experiment, COD and colour 
were measured as initial state.
2.3 Sheet former trials
The influence of re-using treated 
municipal wastewater on paper quality 
has been estimated on the basis of a 
hand sheet. Hand sheets were produced 
from short fibre and long fibre pulp 
in equal shares, refined together in a 
laboratory refiner at a consistency of 
3.5%. Refining energy input into the 
pulp was 150 kWh/t. After refining, the 
freeness of pulp was raised from 20 °SR 
to 31 °SR (Schopper Riegler). Before 
producing the hand sheets, stock was 
again diluted down to a consistency of 
0.5% and introduced into the Rapid 
Köthen sheet former. Original process 
water (white water 1) was used to 
show the current situation in paper 
mills, with these results serving as the 
basis. The exclusive use of AOP-treated 
municipal wastewater is the worst case 
scenario (Sc), whereas the mixed scenario 
represents a possible water reuse. Based 
on the results presented below, the 
following processes and settings have 
been used for the AOP-treatment: ozone 
(total dosage 380 g/m
3
) + UV (total 
dosage 800 Wh/m
3
).
The following properties of the hand 
sheets were measured: colour as L*a*b*- 
values according to the CIE LAB System 
and bending stiffness according to DIN 
53 121, breaking elongation, tensile 
strength as well as the modulus of 
elasticity according to DIN EN ISO 1924-2.
3 Results and discussion
3.1 Characteristics of raw 
municipal wastewater used for 
experiments
Raw municipal wastewater used for 
experiments (Tab. 1) had already been 
partially degraded as it was collected 
from a sequencing batch bioreactor 
(SBR), thus having relatively low COD 
and BOD
5
 values. It was slightly coloured 
and contained a portion of suspended 
solids which were removed prior to the 
AOP-treatment.
Figure 1: Scheme of the laboratory AOP-treatment plant [10]. AOP-advanced oxidation processes.
Slika 1: Shema laboratorijske AOP čistilne naprave [10]. AOP-napredni oksidacijski postopki.
Table 1: Characteristics of municipal wastewater used 
for experiments.
Preglednica 1: Karakteristike komunalne odpadne 
vode uporabljene za poskuse.
Parameter Unit Measured 
value
pH - 8.17
Electric 
conductivity
µS/cm 1144
TSS mg/l 80
BOD
5
mg/l 60
mg/l 126
Colour
436nm m-1 7.73
525nm m-1 5.56
525nm m-1 4.26
The most efficient option for COD 
removal (Fig. 3) was the combination of 
O
3
 + UV (25%). The second best was the 
combination of H
2
O
2
 + UV (19%). The 
least effective for COD removal was the 
H
2
O
2
 (12%). By comparing O
3
 and O
3
 + 
UV treatments, it can be seen that UV 
light contributed to better decolouration. 
This was also true for H
2
O
2
 and H
2
O
2
 + 
UV treatments.
All AOPs tested have been proven 
efficient for the disinfection of municipal 
wastewater, and even low doses of 
ozone resulted in a significant removal of 
microbes (data not showed).
In general, O
3
 combined with UV proved 
to be the most successful in AOP-
treatment of municipal wastewater for 
both colour and COD reduction. With this 
combination, significant colour reduction 
was achieved, whereas the decolouration 
of wastewater intended for re-use was 
especially important for further sheet 
former trials. The experiments with H
2
O
2
 
were not as successful as ozonation 
as regards colour removal, and in this 
case, a combined treatment with UV 
did not give better results. With all AOP 
treatments, only limited COD reduction 
was obtained. H
2
O
2
 proved to be better 
for COD removal than the use of O
3
 
alone and the addition of UV only 
improved degradation. Nevertheless, 
the differences in COD reduction 
between AOP combinations were not 
so significant as for colour removal. The 
results show that by combining different 
AOPs, better treatment efficiency of 
municipal wastewater can be achieved in 
comparison with the use of single AOPs.
3.3. Paper properties
Table 2 shows the mean values of paper 
properties measured in the hand sheets. 
The a*b*-plane of the CIE L*a*b* colour 
system shows the influence of water use 
on the colour of hand sheets. Negative 
a*-values represent the colour green, 
positive values the colour red, negative 
b*-values represent the colour blue, 
positive values the colour yellow. The A*- 
and b*-values of absolutely white paper 
sheets would be zero. The L*-value +100 
is defined as white, 0 as black.
The use of AOP-treated municipal 
wastewater gives the same colour 
coordinates a* and b* of hand sheets 
as the use of white water 1 at a share of 
both 50% and even 100% wastewater 
use. The L*-values are even somewhat 
higher when substituting white water by 
treated wastewater. It can be concluded 
that the reuse of AOP-treated municipal 
wastewater does not impair the 
whiteness of paper.
According to Table 2, the use of AOP-
treated municipal wastewater did not 
impair the strength properties of hand 
sheets compared to the use of white 
water, either. Even an increase in strength 
properties with an increased share of 
AOP-treated wastewater was noticed. 
This might be due to a lower load of 
treated wastewater in comparison 
with white water. It can therefore be 
concluded that the reuse of AOP-
treated municipal wastewater in paper 
production process does not impair the 
mechanical product properties.
4 Conclusions
Considerable effects have been achieved 
by advanced oxidation processes (AOP) 
treatment and improved water qualities 
have been produced. The choice of 
the optimum process(es) and settings 
depends on the wastewater origin and 
on the water quality to be achieved 
RAZISKAVE IN RAZVOJ
Scenario
Colour Strength properties
L* a* b*
Bending 
stiffness
Breaking 
elongation 
Tensile 
strength
Modulus of 
elasticity
Nmm % kN/m N/mm²
100 % WW1 94.9 0.1 3.3 0.18 2.86 2.73 2.707
50% WW1 + 50% 
AOP treated municipal 
wastewater
96.0 -0.4 3.8 0.19 2.87 2.81 2.703
100% AOP treated 
municipal wastewater
96.2 -0.4 3.7 0.20 3.39 3.50 3.065
(requirements of the location for reuse). 
The main treatment aim depends on 
the origin, too. For example, for the 
treatment of municipal wastewater, 
the organic load is not an issue whilst 
disinfection is a major issue. The results 
of AOP experiments performed at raw 
municipal wastewater showed that the 
most effective option for colour removal 
was the combination of ozone (O
3
) + 
ultraviolet irradiation (UV). The least 
effective one was the combination of 
hydrogen peroxide (H
2
O
2
) + UV. The most 
effective option for COD removal was 
the combination of O
3
 + UV, and the 
least effective one was the H
2
O
2
 alone. 
Significant disinfection of municipal 
wastewater was achieved with all four 
tested AOP combinations. The use of 
AOP-treated municipal wastewater in 
Figure 2: Colour removal in municipal wastewater with a combination of different advanced oxidation processes. 
Slika 2: Odstranjevanje barve iz komunalne odpadne vode s kombinacijo različnih naprednih oksidacijskih postopkov.
Figure3: Chemical oxygen demand (COD) removal in municipal wastewater with a combination of different 
advanced oxidation processes.
Slika 3: Odstranjevanje kemijske potrebe po kisiku (COD) iz komunalne odpadne vode s kombinacijo različnih 
naprednih oksidacijskih postopkov.
Table 2: Colour coordinates and mechanical properties of hand sheets produced with white water 1 and AOP 
treated municipal wastewater. AOP-advanced oxidation processes.
Preglednica 2: Barvnometrične in mehanske lastnosti laboratorijskih vzorcev papirja, proizvedenih s sitovo vodo 
1(WW1) in AOP očiščeno komunalno odpadno vodo. AOP-napredni oksidacijski postopki.

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paper production process to substitute 
fresh water did not impair the colour and 
strength properties of paper in laboratory 
trials and is expected to be possible in 
paper mills. The required water qualities 
very much depend on the paper grade 
produced, the raw materials used 
and other specific mill conditions like 
production processes and technologies 
used. The national legislation and 
internal aspects of companies such as 
the economic situation and willingness 
to substitute fresh water by treated 
wastewater have to be considered as 
well. The results show that the use of 
municipal wastewater as an alternative 
water source is possible in paper 
production. This ensures that production 
can be maintained in regions and 
situations lacking fresh water.
Acknowledgement
The study was performed within the 
CORNET 46 EN “AOP4Water” project 
(www.cornet-aop4water.eu). The authors 
are grateful to the funding agencies for 
all the support.
1
 dr.,University of Ljubljana, Faculty of Health 
Sciences, SI-1000, Ljubljana, Slovenia
(E-mail: aleksandra.krivograd@zf.uni-lj.si, 
klara.jarni@zf.uni-lj.si).
2
 Institute for Water of the Republic of 
Slovenia, Hajdrihova 28c, 
SI-1000 Ljubljana, Slovenia.
3
 PTS, Hess-Str. 134, 80797 Munich, Germany 
(E-mail: svenja.bierbaum@ptspaper.de).
6 REFERENCES
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[2] PEREIRA, L. S., CORDERY, I. IACOVIDES, 
I. Coping with water scarcity. Addressing the 
challenges. Springer, 2009, 296 str.
[3] KINSELA, S., GLEASON, G., MILLS, V., 
RYCROFT, N., FORD, J., SHEEHAN, K., MARTIN, 
J. The State of the Paper Industry Monitoring 
the Indicators of Environmental Performance, 
ROBERTS, J. (urednik), Environmental Paper 
Network, 2007, 70 str.
[4] ANGELAKIS, A. Why is water reuse so 
important to the EU? - Drivers, Benefits and 
Trends. Dostopno na spletu:
http://technologies.ew.eea.europa.
eu/technologies/resourc_mngt/water_
use/2004.12.13-A._Angelakis-_Water_Reuse__
final_.pdf (accessed 05/08/2013).
[5] VISVANATHAN, C., ASANO, T. The Potential 
for Industrial Wastewater Reuse. Published 
in “Encyclopedia of Life Support Systems”, 
UNESCO Publication, 2002.
[6]  DURHAM, B., ANGELAKIS, A. N., 
WINTGENS, T., THOEYE, C., SALA, L. Water 
Recycling and Reuse. A Water Scarcity Best 
Practice Solution. Dostopno na spletu: http://
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reuse_a_water_scarcity_solution._Final.doc 
(accessed 05/08/2013).
[7] BRAUNERSREUTHER, M. Wasser mehrfach 
nutzen (use water more than once), Umwelt 
Magazin, 2013, str. 16–17.
[8] BLANCO, Á., NEGRO, C., ORDÓÑEZ, 
R., SAN PÍO, I. Requirements of reclaimed 
water to be used as fresh water for paper 
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environmental technology – New concepts to 
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A. (uredniki), PTS, Munich, 2009, proceedings: 
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Paper Madrid. Dostopno na spletu:
http://www.holmen.com/Sustainability/
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activities-at-Holmens-units/Holmen-Paper-
Madrid (accessed 05/08/2013).
[10] KRIVOGRAD KLEMENČIČ, A., KRZYK, 
M., DREV, D., BALABANIČ, D., KOMPARE, B. 
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various combinations of advanced oxidation 
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vol. 25, št. 42, str. 29–36.
MOŽNOSTI VKLJUČITVE PAPIRNE 
INDUSTRIJE V PROCES BIORAFINERIJE
POSSIBILITIES OF BIOREFINERY CONCEPT 
IMPLEMENTATION IN PAPER INDUSTRY
Mija SEŽUN
1
, Janja ZULE
2
IZVLEČEK
V članku je predstavljena možnost celovitejše izrabe lesne biomase v papirni in lesnopredelovalni panogi oziroma vpeljava 
koncepta biorafinerije v proizvodnjo. V papirnicah z integrirano proizvodnjo lesovine in v lesnopredelovalnih obratih ostajajo 
večje količine drevesne biomase, na primer skorja, grče, žagovina itd. Tovrstni ostanki so bogat vir komponent in kemikalij, na 
primer polimernih sladkorjev, polifenolov, različnih olj, smole, škroba in proteinov. Lesne ostanke je možno učinkovito pretvoriti v 
sekundarno gorivo bioetanol oziroma bi bilo smotrno iz njih izolirati spojine z dodano vrednostjo, ki bi našle svojo uporabnost v 
različnih industrijskih panogah. Lesna biomasa je v nasprotju z nafto in fosilnimi materiali obnovljiv surovinski vir, zato je njegova 
optimalna izraba bistvenega pomena za nadaljnji razvoj.
Ključne besede: biorafinerija, lesni odpadki, bioetanol, specialne kemikalije, alternativi viri.
ABSTRACT
The article describes the possibility for a more comprehensive exploitation of wood biomass in papermaking and wood 
converting industry by introducing a concept of biorefinery. In wood converting plants and paper mills with integrated 
production of mechanical pulp, substantial quantities of wood material such as bark, knots and sawdust are left behind. These 
residues represent a rich source of components and chemicals, for example polymeric sugars, polyphenols, oils and fats, starch, 
resin and proteins. Woody residues can be efficiently converted into secondary fuel bioethanol or else it is reasonable to extract 
added-value compounds for application in different industries. In contrast to oil and fossil fuels, wood biomass is a renewable 
raw material. Its optimal exploitation is therefore of key importance for further development.
Keywords: biorefinery, wood residues, bioethanol, specialty chemicals, alternative sources.
1 Uvod
Temelj energetske ekonomike v 
prihodnosti je iskanje alternativnih 
možnosti pridobivanja energije. Obnovljivi 
viri so ena izmed najbolj perečih tem 
današnjega časa. Zavedamo se, da so 
potrebe po energiji vedno večje, obenem 
pa se njene zaloge manjšajo.
Tako imenovane biorafinerije so v zadnjem 
času med najpomembnejšimi raziskovalnimi 
temami s področja obnovljivih virov. Njeni 
pozitivni učinki so razlog za relativno 
veliko finančno podporo s strani EU 
raziskovalnega programa (Petrič, 2011). 
Slovenija si že kar nekaj časa prizadeva 
za razvoj in vpeljavo procesa biorafinerije, 
vendar žal brez konkretne realizacije. 
Prednost omenjenega procesa je tudi 
zmanjšanje vplivov na okolje in omilitev 
problema globalnih klimatskih sprememb 
(Petrič, 2011).
Okolje igra v papirniški industriji še prav 
posebej veliko vlogo, saj so energetske 
porabe velike, istočasno pa je omenjena 
industrijska panoga znana po nastanku 
znatnih količin odpadkov. Po podatkih 
slovenske papirne industrije je bilo 
ugotovljeno, da povprečne skupne 
količine lesnega odpadka v slovenskih 
papirnicah znašajo okoli 30.000 ton/
leto. Glede na količine bi bilo smiselno 
poiskati rešitev ponovne uporabe 
oziroma izrabe slednjega. Poleg tega, 
da so količine dokaj velike, predstavlja 
odpadek za podjetje precejšen strošek, 
hkrati pa negativno vpliva na okolje. 
Izboljšanje okoljske uspešnosti, zlasti 
zmanjšanje energijske porabe, izboljšanje 
učinkovitosti rabe vode in zmanjšanje 
onesnaženosti zraka so dolgoročni cilji za 
papirno industrijo.
Integrirana industrija celuloze in papirja 
je trenutno eden izmed najboljših 
predstavnikov zgodnje faze vpeljave 
procesa lignoceluloznih biorafinerij v 
gozdarskem sektorju.
Dandanes obstaja veliko zanimanje za 
sodelovanje industrije papirja in celuloze 
z drugimi industrijskimi panogami, 
predvsem s kemično industrijo. Ena  
izmed idej je bila, da bi se v proizvodnjo 
celuloze vključil proces uplinjevanja 
biomase materialov (les, sekanci, 
kmetijski odpadki …), katerega produkt 
bi bil sintezni plin. Sintezni plin lahko 
pretvorimo v različna zelena goriva in 
kemične substrate, kot so na primer 
ocetna kislina, metanol, metil acetat 
… Poleg produktov se pri proizvodnji 
sinteznega plina sprošča tudi toplota, 
ki bi se lahko uporabila kot energija. 
V papirniški industriji bi tako zmanjšali 
nakup plina in električne energije  
(Luguel, 2008).
2 Koncept biorafinerije
»Biorafinerija« (slika 1) je nov izraz, ki 
se je razvil iz pojma »rafinerija nafte« V 
naftnih rafinerijah pridobivamo energente 
in kemikalije, prav isto pa počnemo tudi 
v biorafinerijah, le da je surovinski vir 
drugačen. Namesto neobnovljive nafte 
v biorafinerijah uporabljamo trajnostne, 
obnovljive lignocelulozne materiale, tudi 
les (Petrič, 2011).
Kamm in sodelavci (2004) ter Dyne 
in sodelavci (1999) opisujejo tri vrste 
biorafinerij glede na vhodne surovine, 
in sicer: biorafinerije, katerih vhodni 
materiali so pridelki v celoti (pšenica, rž, 
koruza …), le-te pa vključujejo mehansko 
predobdelavo. Naslednja vrsta so tako 
imenovane »zelene biorafinerije«.