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Research Journals >
Indian Journal of Natural Products and Resources (IJNPR)
[Formerly Natural Product Radiance (NPR)] >
NPR Vol.4 [2005] >
NPR Vol.4(5) [September-October 2005] >
| Title: | Fibre |
| Issue Date: | Oct-2005 |
| Publisher: | CSIR |
| Abstract: | Hemp
(Cannabis sativa Linn.) is grown for its strong
stem fibre and its absorbent core. Drying of hemp stems is an important stage in
the production of this fibre crop. Strategies for harvesting and managing the
cut crop are needed that maximize the stem drying rate so that periods of good
weather can be used to enable a consistent high-quality fibre to be produced.
The equilibrium relative humidity for a range of stem moisture contents from 7
to 35% wet basis was determined for hemp stems between 5 and 40°C and expressed
using the modified Halsey equation. Drying behaviour of stems exposed to excess
air showed that stems stripped of leaves and heads immediately before cutting
dried significantly faster than unstripped, control stems. Retted stems dried at
least four times faster than unretted controls. Drying of swaths similar to
those produced by a commercial cutter, showed that stripped stems dried
significantly faster than unstripped under good weather conditions. Thus,
stripping was confirmed as having potential to accelerate swath drying. When
chopped stems, in a normal width of swath and spread to twice the width were
compared with unchopped controls, the chopped material dried but also wetted
faster. Because spreading exposed the stems more to solar radiation, wind and
rainfall, both drying and wetting were enhanced. Turning a partially dried
swath, particularly of chopped material, was effective in promoting drying where
atmospheric conditions were favourable. Sufficient data are presented to allow
modelling of drying of the materials in swath [Bruce DM,
Hobson RN, Hamer PJC and White RP, Drying of Hemp for Long Fibre Production, Biosyst Eng, 2005, 91 (1),
45-59]. |
| Page(s): | 419-420 |
| ISSN: | 0975-1092 (Online); 0972-592X (Print) |
| Source: | NPR Vol.4(5) [September-October 2005]
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