Assessing the treatment costs and the fertilizing value
of the output products in digestate treatment systems
K. Golkowska, I. Vázquez-Rowe, V. Lebuf, F. Accoe and D. Koster
ABSTRACT
The objective of this paper was to advance towards
finding sustainable solutions to deal with biogas
digestate and contribute to faster development of the market for digestate treatment products. The
study compares digestate treatment costs through four different treatment plants, estimates the
potential fertilizing and humus value (PFHV) of the derived products and allocates the cash
flows to
show the possible regional bene
fits. The treatment costs for the pre-dried solid fraction of digestate
ranged from
€19 to €23/tonne output. These costs may be covered by vending treatment products at
a price reaching at least 34
–41% of their PFHV (ca €55/tonne). Treatment of raw digestate generates
high operating costs (
€216–247/tonne output), much higher than the PFHV of the products (ca €35–
51/tonne). For such systems either the treatment has to be
financially subsidized by the authorities
or
€13–32/tonne input should be covered by the substrate deliverers as a disposal fee. Nevertheless,
a well-prepared investment concept in this
field may allow the local binding of up to 80% of total cash
flows. Finally, the current difficult market situation of the treatment products can be primarily
improved by clearing their legal status at European level.
K. Golkowska (corresponding author)
I. Vázquez-Rowe
D. Koster
Resource Centre for Environmental Technologies,
CRP Henri Tudor,
6A, Av. des Hauts-Fourneaux,
L-4362 Esch-sur-Alzette,
Luxembourg
E-mail: katarzyna.golkowska@tudor.lu
V. Lebuf
F. Accoe
Flemish Coordination Centre for Manure
Processing,
Abdijbekestraat 9,
8200 Brugge,
Belgium
Key words
|
digestate treatment, market value, mineral fertilizer, nutrient recovery, regional cash
flow, treatment costs
INTRODUCTION
Treatment of biogas digestate is currently an important issue
for several areas with high livestock density in Europe, such
as Belgium, the Netherlands, as well as for certain regions in
Italy or Germany (
). These regions suffer
from the surplus of nutrients in soils, due to intensive live-
stock farming causing diffuse emissions that have led to
important environmental burdens (
). In
this context, treatment allows reducing emissions related
to the spreading of untreated digestate (
), but also produces easily
exportable products with reduced water content and
volume.
Digestate treatment processes, depending on the applied
technology, generate several different outputs, such as dried
solid fraction, ammonium sulfate solution or reverse osmo-
sis concentrate, with different characteristics and fertilizing
parameters. In the current market and legal situation these
separated streams are usually remixed after the treatment
and disposed of by the farmers as a single output product.
This application procedure, however, does not take
advantage of the fertilizing potential and easier applicability
of separated streams, but mainly leads to cheaper transport
of the nutrients captured in those products out of the region.
A more sophisticated use of treatment outputs (with separ-
ated nutrient streams) without mixing them could help to
close the natural nutrient cycle by substitution of commonly
used mineral fertilizers (
;
). This important issue gains importance due to
the continuous price increase of mineral fertilizers linked
to depleting phosphorus rock (
) and
unstable prices of fossil fuels. However, there are still several
constraints preventing development of the market trading
digestate treatment products. These include restrictions
and obstacles linked to the legal status (waste or fertilizing
product), lack of acceptance by farmers (end users) partially
due to a limited knowledge concerning the fertilizing effects
of the treatment products, little information regarding
output characteristics for different treatment technologies
and, consequently, dif
ficulties in estimating fertilizing and
market value.
656
© CRP Henri Tudor 2014
Water Science & Technology
|
69.3
|
2014
doi: 10.2166/wst.2013.742
Therefore, the main objective of this paper is to help in
advancing towards
finding sustainable solutions to deal
with digestate from biogas plants. For this, a comparative
analysis of digestate treatment costs in four different treat-
ment plants is performed together with an attempt to
assess the potential fertilizing and humus value (PFHV)
of the output products. Finally, the results will allow assess-
ment of useful implications for the faster development of
this emerging market.
METHODS
Analyzed treatment systems
The current study compared four digestate treatment tech-
nologies: drying with
fixed bed dryer (A), drying with
fluidized bed dryer and pelletizing (B), biological treat-
ment, reverse osmosis and drying with
fluidized bed
dryer (C) and reverse osmosis and drying with double
boiler (D). The data for plants A
–C were delivered directly
by plant managers, while for plant D the information was
retrieved from
. Treatment
systems A and B deal with a pre-treated solid fraction of
digestate reaching a dry matter (DM) content of 56%.
Such input characteristics were obtained by mixing differ-
ent pre-dried streams or mixing untreated digestate with
completely processed dried digestate. Plants C and D pro-
cess raw digestate with DM content reaching ca 9% of
fresh matter (FM). In these plants digestate is separated
and, subsequently, both solid and liquid fractions are pro-
cessed in parallel. The simpli
fied chart flows of the
treatment plants are given in
. These schemes
do not include any by-products of the treatment. In
plants A, B and D the water vapor emissions from the
acid washer are exhausted into the air, while the permeate
is either directly discharged to a watercourse (plant C) or
sent to the lagoon for cooling, biological reactivation and
further water polishing, and subsequently discharged to
the surface water as well (plant D).
Based on the substrate description given by the plant
operators and the typical average characteristics of biogas
digestate from Flanders (VLACO (Vlaamse Compostorgani-
satie
vzw),
personal
communication),
the
nitrogen,
phosphorus and potassium composition of the input streams
was calculated for the different treatment technologies. The
Figure 1
|
Schematic chart
flows of the analyzed treatment systems. Light gray boxes indicate currently intermediate products that are potentially valuable for agricultural purposes, while
dark gray boxes show current
final products.
657
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
stackable input streams for plants A and B contained 14.9
–
15.8 kgN/t
FM
, 21.3
–22.6 kgP
2
O
5
/t
FM
and 14.2
–16.2 kgK
2
O/
t
FM
. For plants C and D the calculated characteristics of the
input were the following: 4.3
–4.6 kgN/t
FM
, 3.8
–3.9 kgP
2
O
5
/
t
FM
, 3.5
–3.7 kgK
2
O/t
FM
. The nutrient fractions assigned to
intermediate and
final digestate streams, e.g. solid or liquid
fractions, were either calculated based on
for plants A
–C or extracted from
for plant D. More detailed characteristics on
the output streams are given in
Calculation of PFHV
The PFHV for the treatment products was calculated based
on the content of accountable P
2
O
5
, K
2
O, N and humus-C,
as well as the current market price for these nutrients. A
similar method has been applied by
to calculate
PFHV of digestate. This approach allows an easier assess-
ment of PFHV than comparison with different mineral
fertilizers existing on the market and containing prede
fined
mixes of different P, K and N compounds. Uptake ef
fi-
ciency of total P
2
O
5
, K
2
O and N is presented in
Solid dried digestate was the dominating fraction in all
the mixed outputs obtained in the different treatment
plants. Therefore, 30% of total N was assumed as contribut-
ing to the fertilizing value. For the second product obtained
in plant D (ammonium sulfate), 90% uptake of N was con-
sidered. Current prices for P
2
O
5
, K
2
O and N were retrieved
from
. Following the case studies presented by
, the humus C content was
assumed to be 60
–70 kg/tonne for the mixed products (cal-
culated humus-C content was assumed as ca 18% of
organic matter (OM), while OM was assumed as ca 40%
of DM). For ammonium sulfate no humus-C content was
taken into consideration, since the information about the
possible content was not available.
Calculation of treatment costs
Treatment costs were computed for the different treatment
processes existing in plants A
–D. All the costs linked to
the substrate transport to the plant, product transport out
of the plant as well as spreading were excluded from the
system boundaries of the assessment. For plants A and B
the pre-treatment steps (and, consequently, their costs),
which took place before substrate delivery to the plants,
were not included in this evaluation. No subsidies or any
form of
financial support were considered. Finally, the cal-
culations
do
not
include
VAT
(value
added
tax)
computation.
The treatment systems were assumed to be operational
during a 20 year period. Treatment costs were grouped in
three categories: (1) total investment costs, i.e. buildings,
installations, infrastructure, machines, land acquisition;
(2) operational costs, i.e. power and heat supply, materials,
chemicals, internal transport, machine operating costs;
and (3) manpower costs linked to the plant workers. All
the investment costs of (1), except for the machines,
were assumed to be
financed with a 20-year-loan credit
with the base rate of 6%. For the internal transporting
vehicles different loan times of 2
–20 years were considered
depending on their lifetime. Due to the con
fidential char-
acter of the information required, data were not retrieved
directly from plant operators. Consequently, most of the
financial data were obtained from literature, adjusting the
data to the speci
fic operating parameters delivered by
the plant operators. In addition, calculations included an
in
flation rate of 3%. A discount rate of 4% was used to cal-
culate back the future expenditures to the present net
value.
The treatment plants presented different heat and power
demands and developed very speci
fic supply mechanisms
based on biogas, natural gas, mixed scenarios, etc. To
Table 1
|
Characteristics of the currently received output products for treatment systems A
–D
Plant A
Plant B
Plant C
Plant D
Product
Dried digestate
þ
(NH
4
)
2
SO
4
Pellets
Dried digestate
þ reverse
osmosis concentrate
Dried digestate
þ reverse
osmosis concentrate
(NH
4
)
2
SO
4
DM
%FM
90
90
85.6
86.7
–
Total N
kg/t
FM
22.8
21.6
22.0
23.7
35
P
2
O
5
kg/t
FM
24.4
32.3
33.8
22.5
–
K
2
O
kg/t
FM
31.9
18.0
15.9
7.0
–
DM: dry matter; FM: fresh matter.
658
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
achieve higher transparency and comparability of the treat-
ment costs the following heat and power
financing
scenario has been developed: treatment plants acquire natu-
ral gas from the grid and generate the necessary heat in their
own combined heat and power units. Produced electricity is
used to cover the energy demand of the plants, while the
surplus is sold on the market. The costs of natural gas,
reduced because of the revenues arriving from the electricity
sold, constitute the energy and heat supply costs of the treat-
ment plants.
RESULTS AND DISCUSSION
The obtained annual net treatment costs are shown in
, together with the speci
fic treatment costs in relation
to 1 tonne of incoming product. The speci
fic treatment costs
based on the output volume are much lower for plants A and
B. This is mainly due to the previous pre-treatment steps that
the incoming products underwent before entering the plants
(the costs and energy input of the pre-treatment are
unknown and not included in this study). Plants A and B
deal with stackable inputs with high DM content. Conse-
quently, the volume reduction during the treatment, as
well as the difference in treatment costs based on the
input and output volume are considerably lower than for
those plants that are directly treating raw digestate (i.e. C
and D). For the latter, the important volume reductions
that are achieved during the treatment process result in
increased speci
fic investment (since more treatment steps
and installations are necessary), as well as higher chemical
and material costs (
). In contrast, the
speci
fic costs linked to internal transport and maintenance
are much higher in plants A and B. This is a consequence
of dealing with stackable substrate, which requires the use
of transporting machines (lift trucks), while in plants C
and D the input and its larger part after separation have
liquid form and can be easily forwarded with the pumping
systems. The speci
fic annual net costs of manpower increase
in plants C and D due to higher complexity of these systems.
In general, the highest speci
fic costs were calculated for
plant D, which runs in pilot scale and treats much less
input than the other plants. Moreover, besides the
Table 2
|
Nutrient uptake ef
ficiency for different digestate related products
Type of product
Nutrient
Uptake ef
ficiency (%)
All types of digestate
a,b
P
2
O
5
100
All types of digestate
a,b
K
2
O
100
Untreated digestate
þ liquid fraction
of digestate
a,b
N
60
Solid fraction of digestate
þ
compost
a,b
N
30
Dried digestate
a,b
N
30
Ef
fluent after biological treatment
a,b
N
100
Mineral fertilizer
a,b
N
100
(NH
4
)
2
SO
4
– solution from air
scrubber
a,c
N
90
–100
Mineral concentrate from reverse
osmosis
d
N
70
–100
a
b
.
c
J. De Vries, personal communication.
d
.
Table 3
|
Calculated annual treatment costs for the digestate treatment systems A
–D together with the calculated PFHV
Parameter
Unit
Plant A
Plant B
Plant C
Plant D
Input volume
t/a
60,000
108,000
55,000
11,400
Output volume
t/a
37,500
79,000
3550
2000
Annual treatment costs
€/a
838,000
1,510,000
877,000
431,000
Input annual speci
fic treatment costs
€/t input
14.0
14.0
15.9
37.8
Power and heat
€/t input
6.04
4.30
5.95
14.20
Investment
€/t input
2.35
2.89
4.15
7.14
Chemicals and materials
€/t input
0.11
0.42
0.79
9.52
Internal transport and maintenance
€/t input
2.16
2.70
0.24
1.15
Manpower
€/t input
3.31
3.68
4.82
5.81
Output annual speci
fic treatment costs
€/t output
22.3
19.1
246.9
215.7
PFHV
€/t output
54.9
56.5
51.4
34.7
PFHV: Potential fertilizing and humus value.
659
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
dimensions of this plant, dif
ficulties in estimating the tech-
nological costs (due to application of non-standard
technologies) were also an important source of uncertainty,
which may have led to the overestimation of the investment
costs (
).
The calculated PFHV for the treatment products are
compared in
with the annual speci
fic treatment
costs calculated on the product basis. This comparison
suggests that if the treatment products for plant A and B,
dealing with stackable digestate, were to be sold at
€25/
tonne (which constitutes only 34
–41% of their PFHV), the
treatment costs would be completely covered by sale reven-
ues. However, it is important to understand the very speci
fic
financial situation of plants treating stackable digestate.
Depending on the local market conditions, characteristics
and origin of the incoming digestate streams, plants might
be either paid for
‘disposing of’ such type of digestate or
forced to acquire their substrate from the digestate
producers.
In plants C and D, even if the products were to achieve
their PFHV, there would still be costs of
€13–32/tonne input
that would need to be covered either by the digestate deli-
verers or some form of
financial subsidy. Should the
product be delivered for free, then the complete input
based treatment costs would have to be covered from the
aforementioned
financing sources. For all four scenarios
the evaluation does not include any transport costs, which
need to be either additionally paid by the product end
users or included in the treatment costs, which in the case
of plants treating raw digestate would either lead to
increased substrate
‘disposing’ prices or would have to be
compensated for by higher subsidies for the treatment
installations.
Considering current legislation and the market situation
for digestate treatment products in Europe, the PFHV may
be considered highly theoretical estimations with important
underlying sources of uncertainty (
). In practice,
the price of digestate treatment products does not only
depend on their quality, but also on the application sector
(e.g. agriculture, horticulture, landscaping or hobby garden-
ing), volume produced or geographical location (
;
). In fact, many treatment plants are forced
to give their products away for free, others manage to sell at
prices ranging from
€2 to €10/tonne, while other plants
export over longer distances and sell their products for
nearly
€30/tonne (including current transporting costs of
ca
€8.50/tonne and 100 km).
All discussed treatment costs, which arise during the
whole operating period of the treatment plant, can be
divided into costs contributing to the development of the
regional or global market players. To estimate added
value of the treatment installations for the regional
market, the calculated cash
flows were divided into those
transferred out of the region (partial investment costs
including machines, fuel, materials and chemicals and
not-locally sourced energy) or those that remained in the
region (partial investment costs, internal transport exclud-
ing
fuel,
manpower,
locally
sourced
energy).
The
calculated cash
flows assigned to the region are presented
in
. The largest part of the cash
flow in each invest-
ment is always linked to energy supply costs. In plants A, C
and D the energy is partially or completely generated from
biogas. This strongly increases the regional cash
flow as
compared to plant B. Substituting the use of fossil fuel
based energy with locally produced renewable energy
would enhance the regional cash
flows for plants A and
B, allowing local binding of 62
–78% of the total investment
costs. In contrast, if for analogue plants the entire required
energy were to be sourced from the fossil fuels only 24
–
41% of the invested money would stay in the region.
This is important information to be analyzed by potential
investors, which can take decisions helping to create
additional local advantages for the treatment systems
through local binding of capital and generating safe jobs
in the
field of green energy (
;
).
CONCLUSIONS
Treated products cause less environmental emissions, and
are cheaper and easier to transport, but may also help
close the natural nutrient cycle by substituting mineral ferti-
lizers (
;
).
Low demand for products derived from digestate treatment
and their extremely low market price are not in accordance
Table 4
|
Regional cash
flows valid for the current energy supply system and renewable
or fossil fuel based energy supplies
Regional cash
flow
Plant A
Plant B
Plant C
Plant D
Current energetic scenario
70%
42%
78%
62%
Complete change to locally
sourced energy
þ8%
þ22% –
–
Complete change to the fossil
fuel based energy
35%
–
37%
38%
660
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
with their real fertilizing and humus value. In the current
market
situation,
the
treatment
costs
for
stackable
pre-dried digestate could be covered by selling treatment
products even if
<50% of the fertilizing value were to be
returned. Dealing with raw digestate constitutes a much
more complex endeavor. Such treatment is more expensive
and cannot be
financed only by selling the treatment pro-
ducts even if the PFHV would be reached. For this reason
possible
financial support schemes, such as subsidies or
digestate disposal fees have to be proposed on the national
or European level to improve the market situation for the
output products and to assure the existence basis for the
treatment plants (
). Furthermore, strategic
planning of the treatment plant may lead to the regional
binding of up to 80% of the whole invested capital, contri-
buting to the development of the region by creating safe
green jobs in the agricultural sector.
Further development of the digestate product market
can be triggered by creating clear and supportive legis-
lation at European level, i.e. regulation of the outputs
status (product or waste). Marketing campaigns would
help to inform target groups regarding the fertilizing poten-
tial of digestate treatment products, while an initial
support system for the farmers substituting industrially pro-
duced mineral fertilizers with digestate treatment products
may increase their willingness to use these fertilizing
agents.
ACKNOWLEDGEMENTS
This study has been developed within the frame of the
ARBOR project with
financial support from the European
Union (EU) INTERREG IVb programme. The authors
would like to thank Evi Michels, Céline Vaneeckhaute
and Erik Meers (Gent University), Vincent Hallau (Störk
GmbH) and Aksel Meier (Amandus Kahl GmbH & Co.
KG) for their help regarding data collection, as well as
Jerke de Vries and Paul Hoeksma (Wageningen University)
and Torsten Rehl and Joachim Müller (University of Hohen-
heim) for valuable scienti
fic exchange.
REFERENCES
Bakx, T., Membrez, Y., Mottet, A., Joss, A. & Boehler, M.
État de l
’art des méthodes (rentables) pour l’élimination, la
concentration ou la transformation de l
’azote pour les
installations de biogaz agricoles de taille petite/moyenne
(State of the art methods (cost) for the elimination,
concentration or transformation of nitrogen produced in
average/small sized agricultural biogas plant)
. Federal
Department for the Environment, Transports, Energy and
Communication (DETEC), Bern, Switzerland.
Barth, J.
Quality and markets for compost and digestion
residues in Europe. The 1st Baltic Biowaste Conference,
Tallinn, Estonia.
http://www.recestonia.ee/ecn/presentations/
(accessed 3 June 2012).
Brouwer, F., Hellegers, P., Hoogeveen, M. & Luesink, H.
Managing nitrogen pollution from intensive livestock
production in the EU. Report 2.99.04, Agricultural Economics
Research Institute (LEI), The Hague, The Netherlands.
Döhler, H. & Wulf, S.
Technical Digestate Treatment –
Advantages, Limitations, Costs
. KTBL, Biogas Europe 25-2
October 2011, Nantes, France.
(accessed 18 June 2013).
Fixen, P. E. & Johnston, A. M.
reserves: a view to the future
. Journal of the Science of Food
and Agriculture
92 (5), 1001–1005.
FMD (Flemish Manure Decree)
Decreet van 6 mei 2011
houdende wijziging van het Mestdecreet van 22 december
2006 (Decree of 6 May 2011 amending the Manure Decree of
December 22, 2006).
http://www.vcm-mestverwerking.be/
information/index_en.phtml?informationtreeid=26
(accessed 30 May 2013).
Goldstein, N.
Organic recycling trends in the European
Union. BioCycle
52 (3), 32–34.
Golkowska, K., Vázquez-Rowe, I., Benetto, E. & Koster, D.
Life cycle assessment of ammonia stripping treatment of
biogas digestate. Proceedings of the Fourth International
Symposium on Energy from Biogas and Waste
, Venice, Italy.
Holm-Nielsen, J. B., Al Seadi, T. & Oleskowicz-Popiel, P.
future of anaerobic digestion and biogas utilization
Bioresource Technology
100 (22), 5478–5484.
Kellner, U., Delzeit, R. & Thiering, J.
Digestate treatment: The
in
fluence of the location and size of the plant on the cost.
Berichte über Landwirtschaft
89 (1), 38–55.
Lebuf, V., Accoe, F., Vaneeckhaute, C., Meers, E., Michels, E. &
Ghekiere, G.
Nutrient recovery from digestates:
techniques and end-product. Proceedings of the Fourth
International Symposium on Energy from Biogas and Waste
,
Venice, Italy.
Leifert, I. & Oechtering, A.
Germany – Marketing concept for
quality products from organic resources, RETERRA,
European Compost Network Workshop, 13 June 2012.
(accessed 3 June 2013).
Mouat, A., Barclay, A., Mistry, P. & Webb, J.
Digestate
Market Development in Scotland. Report OPR080
– 801,
Zero Waste Scotland, Stirling, United Kingdom.
files/wrap/Zero%20Waste%20Scotland%
20-%20Digestate%20Market%20Development.pdf
(accessed
5 June 2013).
RAL, Deutsches Institut für Gütesicherung und Kennzeichnung e.V.
RAL-Gütesicherung Kompost Chargenuntersuchung,
661
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
Prüfzeugnis PZ-Nr.: 9999-1301-014 Gärprodukt
flüssig (RAL
Quality Assurance Compost batch analysis, Certi
ficate No.:
9999-1301-014 Liquid digestate).
docs/guetesicherung/Pruefzeugnis_Gaerprodukt_
(accessed 6 June 2013).
Rehl, T. & Müller, J.
Life cycle assessment of biogas digestate
. Resources Conservation and
Recycling
56 (1), 92–104.
Vaneeckhaute, C., Meers, E., Michels, E., Christiaens, P. & Tack,
F. M. G.
Fate of macronutrients in water treatment of
digestate using vibrating reversed osmosis
. Water, Air & Soil
Pollution
223 (4), 1593–1603.
Vaneeckhaute, C., Meers, E., Ghekiere, G., Accoe, F. & Tack,
F. M. G.
a
Closing the nutrient cycle by using bio-
digestion waste derivatives as synthetic fertilizer
substitutes: a
. Biomass and Bioenergy
55,
175
–189.
Vaneeckhaute, C., Meers, E., Michels, E., Buysse, J. & Tack,
F. M. G.
b
application of bio-based mineral fertilizers in modern
agriculture
. Biomass and Bioenergy
49, 239–248.
Vázquez-Rowe, I., Golkowska, K., Lebuf, V., Accoe, A., Benetto,
E. & Koster, D.
To treat or not to treat? Environmental
assessment of digestate drying technologies using LCA
methodology. 13th World Congress on Anaerobic Digestion.
Recovering (bio)Resources for the World
, Santiago de
Compostela, Spain.
Velthof, G. L.
Synthesis of the research within the framework
of the Mineral Concentrates Pilot. Alterra Report 2224,
Wageningen University & Research Centre, Wageningen,
The Netherlands.
VHE, Verbände der Humus- und Erdenwirtschaft (Associations of
Humus and Soil Management)
Entwicklung des
Reinnährstoffpreise von 5/2007
–5/2013 (Evolution of the
nutrient prices from 5/2007 to 5/2013).
anwendung/kompost-in-der-landwirtschaft/wertigkeit
(accessed 3 June 2013).
VLACO (Vlaamse Compostorganisatie vzw)
Ecologische en
economische voordelen digestaat (Ecological and economic
bene
fits of digestate).
http://www.vlaco.be/professionele-
verwerking/eindproducten/eampe-digestaat
(accessed
30 May 2013).
First received 11 July 2013; accepted in revised form 31 October 2013. Available online 25 November 2013
662
K. Golkowska et al.
|
Assessing the costs and value of output products in digestate treatment systems
Water Science & Technology
|
69.3
|
2014
Copyright of Water Science & Technology is the property of IWA Publishing and its content
may not be copied or emailed to multiple sites or posted to a listserv without the copyright
holder's express written permission. However, users may print, download, or email articles for
individual use.
Wyszukiwarka
Podobne podstrony:
Wartość nawozowa pofermentu i gnojowicy Włochy 2016
referat koszty wytworzenia Word 97 gotowe, Rachunkowosc zarzadcza
wyniki wartości odżywczej owoców różnych odmian porzeczki czarnej(1), Technologia żywnosci i Żywieni
9 Wartość nawozowa
Pomiot ptasi i słoma właściwości, sposoby stosowania,wartość nawozowa
RACHUNKOWOŚĆ-de vilk, koszty[2], Koszty - wyrażone wartościowo zużycie środków pracy (śr
referat koszty wytworzenia Word 97 gotowe, Rachunkowosc zarzadcza
Potencjał nawozowy pofermentu z pozostałości z farmy i przemysłu agro Hiszpania 2012
Instalacja SW 2014
Maszorek Szymala, Anna; Janiak, Martyna Uzależnienia wśród uczniów różnych poziomów kształcenia (20
Właściwości nawozowe i skład chemiczny różnych rodzajów pofermentu i kompostu Włochy 2010
Państwo jako najwyższa wartość narodowa w widzeniu bohaterów literackich różnych epok, prezentacje
Koszty w mikroekonomii (9 stron), Koszty ekonomiczne to wartość wszystkich zasobów (czynników) użyty
Opracowania różnych tematów, Praca jaka najważniejsza wartość człowieka, PRACA JAKO NAJWAŻNIEJSZA WA
WA RADEK, 1 ) Charakterystyki mechaniczne n = f ( M ) dla = /2 oraz dwóch różnych wart
Państwo jako najwyższa wartość narodowa w widzeniu bohaterów literackich różnych epok, SZKOŁA, język
koszty (z różnych stron internetowych), Administracja UKSW Ist, Administracja UKSW IIst, fundusze U
więcej podobnych podstron