Agriculture Reference
In-Depth Information
2. The second difficulty to overcome relates to
the abrasive nature of the plant. This can result
in increased wear of the machinery used and
relatively significant maintenance costs.
3. The process of fibre removal from hemp is
naturally polluting unless precautions are taken
to collect the powder that is produced by the
decortication of the straw.
4. The fourth difficulty arises from the signifi-
cant investment required and the ongoing
maintenance costs. This will be discussed later
on in this chapter, but we can say at this point
that the investment required to establish an
entire factory exceeds the annual turnover of
that factory.
5. Finally, it should be pointed out that work-
ing with hemp creates considerable logistical
problems.
in order to provide an idea of the extent and
difficulties posed by these problems in terms of
volume, surface area and tonnage (Boxes 9.1.
9.2, 9.3 and 9.4).
By volume, taking into account the density:
It is clear from these figures that a signifi-
cant part of the investment required in the
hemp industry is to provide the storage facili-
ties necessary to house the raw materials and
the materials produced when it undergoes
refinement.
Finally, and far from being one of the
most insignificant difficulties, we are working
with a product that has very little unitary value.
In France, hurds are sold by the farmer at
€
80/t.
Consequently, the industrial economy of
hemp will be affected by the differing invest-
ment costs of materials and property, which
will be discussed below.
A certain amount of basic data needs to be
brought to the reader's attention at this point
9.2
Presentation of the Hemp
Decorticating Operation
MATERIAL BALANCE SHEET
FIBRE:29-32%
This presentation will start with fibre and will
then discuss from an industrial perspective the
hurds, powder and hemp seed. First, how-
ever, the essential operation of retting is
discussed.
22-24% technical fibres
4-5% short fibres
3% very short fibres
WOODY CORE: 55%
HEMP
DUST: 10-15%
WASTE: pebbles, wood metal
LOSS: water vapour, dust
9.2.1 Retting
The ultimate use of the fibre, that is to say, the
industrial process, starts with retting.
Fig. 9.1.
Industrial hemp: a breakdown of straw's
derivative products.
Table 9.1.
Principal uses of the constituent parts of hemp.
Fibre
Hurds
Powder
Hemp seed
Paper
Used industrially together
with polymers to produce
composites
Hemp wool used as an
insulator
Felt
Geotextiles
Textiles
String, yarn and rope
Etc.
Animal litter
Chipboard
Mulch
Insulation
Hemp cement
Etc.
Granulated animal
bedding
Fuel
Soil improver
Etc.
Human food
Animal food
Cosmetic products
Cosmetic oils
Oils destined for use in
industry
Etc.
