Theme 3 Production of biofertilizer,
feedstocks and methods from Denmark
Anne-Belinda Bjerre, senior scientist, Ph.D.
Biomass SP April 2012
14 essential plant nutrients in a complete
biofertilizer
Macro-elements: N, P, K, Mg, Ca, S
Micro-elements: Cu, Zn, Mo, Mn, B, Fe, Ni, Cl
All are essential for life cycle of plants,
for biomass production (mainly macro-elements),
vitamins and enzyme production (mainly-micro elements)
Role of macro nutrients N,P,K
Nitrogen (N)
The role of Nitrogen in plants cannot be emphasized enough; Nitrogen encourages development of plants, it is responsible for healthy green leaf growth which is the result of the formation of chlorophyll, which is the main unit for the production of carbohydrates, proteins and oxygen. Therefore, plants that exhibit a Nitrogen deficiency will show symptoms like stunted growth and pale green and yellow leaves. There are also claims that Nitrogen controls, the efficient utilization of phosphorous and Potassium. The plant's dependency on Nitrogen can also lead to retarded root growth and resulting in the foliage turning yellow and pale green and increasing the plant’s susceptibility to disease.
Phosphorous (P)
Phosphorous is responsible for cell development and the promotion of good root growth, particularly in fibrous roots, the vigor of the plant. Plants that suffer from a phosphorous deficiency will have poor root development and show symptoms like stunted growth, though it is not as easily recognizable at those symptoms of Nitrogen deficiency. Phosphorous deficiency is also manifested in the leaves that turn purplish in color when it is not the natural foliage or leaf color of that plant, mainly due to the abnormal increase in the sugar content and the formation of anthocyanin.
Potassium (K)
Potassium is responsible for chlorophyll formation which plays an important part in the strength of cells and encourages flower and fruit formation. Thus Potassium can enhance the ability of the plant to resist plant diseases, insect attacks and cold conditions as Potassium performs a vital role in the formation of starch as well the production and translocation of sugars in the plant. Plants that exhibit symptoms of Potassium deficiency will have like weak stems. Other symptoms of Potassium deficiency include older leaves that are floppy with yellow tips and brown margins. A note of caution though; an excess of Potassium may tend to delay maturity, though, not to be the same extent as nitrogen.
From: http://www.landscape-and-garden.com/garden-soil/basic-nutrients.aspx
Types of fertilizers
Organic fertilizer
bat guano
compost
peat moss
wood ash
bone meal
manure
Biofertilizer (organic fertilizer with added microorganisms)
Inorganic
Most common is NPK
Examples of European Biowaste –starch, crops and forrest
residues, manure waste, household waste, MSW
All feedstocks for biofertilizer
Feedstocks Recycle time
Algae 1 month
Agricultural crops 3 month – 1 year
Grasses 1 year
Shrubs 1 -5 years
Trees 5 -80 years
Oil, Gas and Coal 200 million years
Sustainability -
Recycle (or renewable) times for biomass feedstocks
From : The enginnering of chemical reactions. 2nd ed. Pp532 Oxford, 2005
EU27 biowaste generation
Biowaste and crop fertilizer potential
N P K Dry
matter
Other amounts
Straw - - 0,8-3 % 90% Lignin 5,4 mio tons
Manure 0.4% 0.09 % 0,32% 4,5 % 27 mio tons
Algae 0.5% 0.04% 0.02% 15 % Presently low in Denmark
Clover 0.72% 0.006
%
0.023% 17,5 % Lignin 0,68
%
high
Alfalfa 23
kg/ha*
0.4-
0,8 %
Relativel
y high
25 % 436 million tons in 2006
Worldwide (not much in DK)
Compost 0.6-1
%
0.4-
0.8 %
0.8-
1.2%
ideally 70
%
Guano 11-16
%
3 % 1-3 % %
*plouged in as
green crop
Other important plant constituents
Protein (nitrogen resources) examples:
Legumes (peas, beans, soya, cassava leaves)
Algae (micro and macro algae)
Grasses (clover, other species)
Special crops and herbes (lucerne, lupines)
Clover grass is a nitrogen
fixating plant and lives in
symbioses with
mycoriza
Nutrient elements in plants
Straw stems and leaves contain plant nutrient
elements of
Macro-elements: K, Na, Ca, Si,
Micro-elements: Zn, Cu, Mo,
wood biomass wheat straw, corn stover, rape seed straw Rice straw
low level medium level high level
Straw yields and utilization in Denmark
Potassium (K) products
Produkt Kvælstof (N),
pct. Kalium (K),
pct.
Svovl (S),
pct.
Fosfor (P),
pct.
Magnesium
(Mg), pct.
Flydende
vinasse 0,8 21,0 7,0 - -
Protamylass
e 1,8 0,8 0,5 0,4
Tørret
vinasse <0,4 21,0 16,0 - -
Produkt Kvælstof (N),
pct. Kalium (K),
pct.
Svovl (S),
pct.
Fosfor (P),
pct.
Magnesium
(Mg), pct.
Flydende
vinasse 0,8 21,0 7,0 - -
Protamylass
e 1,8 0,8 0,5 0,4
Tørret
vinasse <0,4 21,0 16,0 - -
Produkt Kvælstof (N),
pct. Kalium (K),
pct.
Svovl (S),
pct.
Fosfor (P),
pct.
Magnesium
(Mg), pct.
Flydende
vinasse 0,8 21,0 7,0 - -
Protamylass
e 1,8 0,8 0,5 0,4
Tørret
vinasse <0,4 21,0 16,0 - -
Plant cell walls contain mainly sugar polymers and lignin
Cellulose
C6 sugars
Hemicellulose
C5 sugars
Sugars are substrate in a biogas reactor
and in a compost process
Lignin the basic structure of humic acid in
soil
• Lignin has large ion
exchange capacity
• Lignin is similar to humic
acid
• Humic acid/lignin is
responsible for fertility in
soil
• Lignin/humic acid is
responsible for retainment
of inorganic plant nutrients
in soil
• Lignin is hardly
biodegradable
• Lignin is inert in a biogas
and bioethanol process
Manure and compost are recognized fertilizers
and soil improvers in all EU countries
Content of nutrients in manure
[Ecochem, 2012]
Methods for construction of an organic fertilizer in
Denmark
Combining a biogas and compost facility
Production of biogas – a renewable energy carrier
Recycling of biowaste resources
Utilization of energy crops from the fields
Production of a mature biological fertilizer
Pasterised - free of pathogens
Free of unwanted seeds
Lignocellulose biorefinery: Phase I
Clark & Deswarte 2008
Energy
and
Fertilizer
Process diagram
Biogas Separation Composting
Pelletizing Bagging
FEEDSTOCKS
(NUTRIENT BASED,
SUGAR BASED)
Bio
gas f
acili
ty
Biogas
Separa
tion u
nit
Fiber
Co
mp
ostin
g f
acili
ty
Fertilizer
MANURE
CLOVER
GRASS
Biogas process
Optimizing the substrate composition
Manure (nutrient elements, 6% organic matter, 94%
water, phosphorous, all other elements)
Plant and plant residues (nutrient elements (K,N), 50-90%
organic matter mainly sugars, 50-10% water)
Biogas (CH4 + CO2)
Nutrient enriched fiber fraction (P,
microelements)
Water with soluble nutrients (NH3, K,..)
Bio-fertilizer production via composting
Organic matter is used as a substrate and decomposed by aerobic
microorganisms (bacteria, fungi and actinomycetes). Optimization of
compost quality is directly linked to the composition and succession of
microbial communities in the composting process
The process occurs normally for 9 to 12 weeks and it is maintained
under aerobic condition as shown in the reaction scheme below.
Composting process is controlled by many factors such as
carbon/nitrogen (C/N) ratio, physical structure of raw material
ventilation rate, moisture content, pH level, temperature, and the
provision of essential nutrients.
Fresh organic waste + O2 𝑚𝑖𝑐𝑟𝑜𝑏𝑖𝑎𝑙 𝑚𝑒𝑡𝑎𝑏𝑜𝑙𝑖𝑠𝑚
stabilized organic mat. (compost) + CO2 + H2O + heat
Compost proces
Optimizing degassed biofibres from biogas plant to a
fertilizer by composting:
Addition of straw facilitates air challens and add more
nutrient elements (especially K and Si)
Addition of other feedstoock and biogas liquid to ajust and
optimise the fertilizer with nutrients
Addition of a biocatalyst converts NH3 to NH4 by pH
reduction and removes odour (Patent Thomsen & Goul,
2006)
Semi-drying the final product
Pastaurising the final product (no pathogens and seeds
left)
Process continued
Pe
llete
tizin
g
Fertilizer in pellets
Baggin
g
Final product
Addition of nitrogen fixating bacteria
Marketing
Proces development
Fertilizer standard product to penetrade the market
Special designed fertilizer to be used at diffrent climate and soil conditions
Design og sale of equipment and plants in EU and Worldwide