HEMP DECORTICATION, THE TRENDS IN APPLICATION AND

HEMP DECORTICATION, THE TRENDS IN
APPLICATION AND POSSIBILITIES OF
BY-PRODUCTS UTILIZATION AND SHIVES
AS A SOURCE OF ENERGY
Jacek Kolodziej, Jerzy Mankowski
parenchyma
beast fibres
leaf epidermis
cambium
epidermis
cavity in pith
wood
Stem structure of fibres plants
2
Fibres plant stem cross-section
3
Flax fibres
Flax fibres
Hemp fibres
The natural fibres, which are
characterized by the:
* high tenacity,
* elasticity,
* low specific weight.
Hemp fibres
The new technology of flax and hemp fibre extraction is based on
decorticator processing of raw flax and hemp stalks and cleaning unit.
The system could be applied as well in case of other bast plants
processing: kenaf, jute and ramie.
A decorticator equipped with hardened elements breaking the stem
performs extraction of fibre from raw hemp straw.
The fibre produced by the decorticator requires additional cleaning to
remove the shives.
The cleaning process is conducted in preliminary cleaning machine,
equipped with sieves and a drum with vertical bars that separate the
remains of wood.
A new decorticating technology allows for significant simplification of
a processing method used so far, improvement of production
economics – through reduction of energy and labour consumption
during extraction of fibre. The processing of hemp and flax straw
proposed here eliminates labour consuming, costly and depending on
weather conditions natural retting processes and additional drying of
straw before processing (maximum moisture content in the straw in
the new technology – 18%).
The processing yield: ca. 1500 kg/h of the raw material
The extraction process provides 25-30% of decorticated fibre, of impurities
content:
20-25% for raw straw
10-15% for retted straw
Decorticator
Using the loosening and cleaning elements of textile machines (the
drum of carding machine) allowed for obtaining fibre containing 4-5%
of impurities.
Fibre parameters
After decortication
After cleaning
Average fibre
impurities content
20-25%
4-5%
Average length of
decorticated fibre
58,9 mm
48,5 mm
Average strength of
decorticated fibre
33,4 cN/tex
22,5 cN/tex
Decorticated fibre
Possibilities of utilization of decorticated fibre
* pulp and paper mass
* composite materials
* nonwoven
Cellulose
The hemp fibre, which contains approximately 75% of cellulose.
Pulp on the base of long fibre is characterised by such
features:
* high mechanical strength,
* resistance to tearing,
* resistance to bending,
* elasticity,
* durability,
* high porosity.
Areas of application of long fibre pulp:
* tee-bag paper,
* low density condenser tissue,
* base for meat packaging paper,
* cigarette filter tissue,
* lenses packaging tissue.
* banknote and securities,
* thin stationery (letter paper)
* base paper for packaging tapes,
* high quality book paper e.g. for Bible
The obtained fibre, as well as waste hurds (shive), can be an excellent
component for production of composite materials.
Ecological disinfection mats made in flax and
hemp fibres
Eco-friendly solution
The technology of producing disinfection mats
based on cellulosic natural fibres allows for easy
utilization of used out products by natural
biodegradation processes and very much lowers the
costs of such utilization. The mats made of natural
bast fibres e.g. flax, hemp, jute fibres are, contrary
to the mats made of man made fibres, completely
biodegradable and thus eco-friendly.
Possible bast fibres for use:
Hemp fibres improve the breaking
strength of the mat.
Flax fibres improve the filling and
water capacity of the mat.
Ecological disinfection mats made of natural
fibres
Breaking strength of the disinfection mats
Tensile strength of the sanitizing mat (surface density 950 g/m2)
Tensile strength of the sanitizing mat (surface density 1350 g/m2)
The mats, basen on nonwoven, developed at the Institute of Natural Fibres &
Medicinal Plants in Poznan, are designed for protection zones that prevent
spreading infectious diseases such as e.g. avian flu.
They are recommended for use at:
• passages in the area of chicken farms,
• cowshed,
• pigsties,
• dairies,
• fodder plants,
• slaughter-house,
• food processing plants,
• apiaries,
• livestock collection points,
• mushroom-growing cellars,
• border crossings.
Examples of application
Use of disinfection mats on passages and
driveways
Use of disinfection mats in farms
In Poland, the Ministry of Economy is working on a document “Energy Policy
for Poland till 2030”. The document is to define in details the strategic
directions of action in the area of energy policy of the state. It is foreseen that
estimated potential of domestic renewable energy resources in agriculture is
about 120 PJ in 10 year horizon.
According to the strategic provisions related to utilization of renewable energy
resources, the main emphasis will be on energy obtained from industrial
plants and biogas in farm biogas plants. The share of renewable
energy in energy balance of the state is gradually growing: from 1.5%
in 2001 up to 7.5% in 2010. It is estimated that the use of renewable energy
in 2020 will reach 14% and 20% in 2030.
The reasons for utilization of flax and hemp biomass as a
source of energy:
ECOLOGICAL FACTORS:
ENVIRONMENTAL
PROTECTION
THE DECREASE OF THE
HARMFUL EFFECT OF
AGRICULTURE ON THE
NATURAL ENVIRONMENT
INCREASE OF THE CROPS
DIVERSITY
ECONOMIC AND SOCIAL
FACTORS:
DECREASE OF THE
UNEMPLOYMENT IN RURAL
AREAS
The basic advantage of the biomass as the raw material for energy is the
significant decrease of the CO2 emission to the atmosphere in comparison
with the coal burning parameters.
The steam of the CO2 emitted during the biomass burning is absorbed in
the plant photosynthesis and it utilized for their growth.
Flax
* Straw yield 7 ton/ha
* Fibre yield 1,7 ton/ha
28
Hemp is a phytosanitary crop, which enables hemp introduction to each crop
ratation, practically after almost every other type of crop.
Industrial hemp is observed as so called “plastic” crop:
• adapts to the new conditions easily,
• with significant forms, biological-morphological and economic value diversity
It is estimated that cultivation of
1 ha of hemp absorbs about
2,5 tons of CO2 whitch contributes
significantly to lessening of the green
house effect.
Hemp
* Straw yield 12 ton/ha
* Fibre yield 2,5 - 3 ton/ha
29
hemp shives
25%
75%
flax shives
fibres
shives
In Poland up to 1990, the utilization
of shives to the production of the
particleboards was popular.
Due to the transformation of the
economy, the and technological
changes- the shives were almost not
applied to the production of the
boards.
Currently the shives are the waste
30
products.
The shives in a loose form are a dangerous material, which can explode during the
burning process, due to the presence of dust.
Unlike wooden chips, shives do not have to be dried before briquette production, which
affects positively the economic aspects of their utilisation.
Composit
materials
Shives
Short fibres
Celuloza
32
The scheme of the line for flax and hemp shives pellets production
1. Loading of the grinding device
2. Grinding device
3. Loading of the cheaping container
4. Cheaping container
5. Loading the pelleting machine (pelleter)
6. Pelleting machine (pelleter)
7. Cooling device
8. Filter
9. Collection of pellets
Pellets made of hemp shives
Length
5-30 mm
Heating value
18 MJ/kg
Weight
650.000 g/m3
Contents of ash
0,5 %
Contents of
sulphur
0,05%
PELLETS are granules of the diameter of 6-10 mm and
length 5-30 mm, which have been pressed with a very
high density in the technological process.
34
The scheme of the line for flax and hemp shives briquettes
production.
1. Cyclone
2. Container (tank)
3. Press
4. Steering panel
5. Stabilizer of briquettes
Production of briquettes
in the INF&MP
Experimental Plant
„Lenkon”
Container
Loading of shives to
the briquetting
machine
Briquetting machine
Stabilizer of
briquettes
The trials conducted at the
INF&MP showed that it is not
necessary to apply the bonding
chemicals additivers
as the shives are bonded by
natural plant substances and high
pressure.
The processors of flax and hemp straw could obtain additional income, by
selling the heating briquettes, produced on the base of flax and hemp shives,
instead of paying for the by-products storage.
According to the European Union regulations, the description of the planned
utilization of by-products from flax and hemp straw processing, is the
necessary condition to apply for the direct subventions.
The energetic value of the plant raw materials
kenaf
15,8
17,2
mallow
17,9
miscantus
18,1
corn
18,7
wheat straw
17,6
rapeseed straw
18,8
hemp shives
18,3
flax shives
17,0
wooden chips
MJ/kg
Heat of combustion of hemp shives and their mixture with rape meal
rape m eal 30% hem p
shives 70%
19,0
rape m eal 70% hem p
shives 30%
19,6
18,8
hem p shives
19,9
rape m eal
18
19
[MJ/kg]
20
Energetic value of two chosen plants compared with hemp
300
249
250
[GJ/ha]
200
150
109
103
winter rapeseed
sugar beet
100
50
0
hemp
The very high energy efficiency is a result of high heat of combustion of hemp
which is 18.8 MJ/kg and high yield of dry matter per hectare.
Energetic value of rapeseed is also high (17.6 MJ/kg). Thus, the conclusion is that
energy efficiency of plants is mainly affected by the level of yield rather than by
the heat of combustion.
Consequently, the profitability of crops cultivated for biomass depends on the
selection of proper plant species which should be characterized by high and
stable yields of dry matter and relatively easy and low energy consuming
agronomic treatments applied.
Application of the production technology of briquettes made of flax
and hemp shives will allow for:
Increase of the share of the renewable energy in the fuel-energetic balance of
the country.
The utilization of shives, which are currently a by-product, as the renewable
source of energy of standard value.
Utylization of the waste raw materials from flax and hemp processing, which
rational usage is the condition for gaining the European Commission
subsides.
Creating new work places in the agriculture sector as well as enlargement of
the scope of the services provided in agricultural processing.
Creating alternative sources of incomes derived from the production of non
food renewable raw materials.
THANK YOU FOR YOUR
ATTENTION !!!
e-mali: jacek@inf.poznan.pl