Lynne Wong's PhD thesis

agitate the mixture in the pot, and assist the separation of pith from the fibre. Coarse fibres
were retained in the pot, finer ones and pith fell through a funnel (cone-shaped vessel) into
a secondary screening pot with 850 micron mesh lid, which retained fine fibres while the
pith fell into a cone-shaped vessel made of fine mesh screen, on which the pith collected,
and through which water flowed out to drain.
Snow (1974) described a fibre-pith separator consisting of a drum made by rolling a piece
of brass screen 30.5 cm wide and 30.5 cm long into a cylinder. The perforations consisted
of 3.18 mm round holes on 6.36 mm centres. Cane, which had previously been shredded
in a 4 L commercial Waring Blendor with 1 L of water at a high speed for 1 minute, was
put into the drum which in turn was put in the apparatus, the tank of which was filled with
water. The drum was rotated for 5 minutes at 18 rpm by means of a 190 W electric motor.
The water containing the pith was drawn off and the pith collected on a Tyler 100 mesh
sieve. The hard fibre was recovered from the rotary drum. Commercial processes also
exist to separate bagasse into fibre and pith for the manufacture of paper and fibre board
(Keller 1966, Atchison 1971).
Another effective method for fibre extraction is the sample preparation method currently
used in Mauritius for direct cane analysis for pol % cane and fibre % cane (Anon., 1991).
This involves shredding the cane with a cane chipper (Fig 2.2). A mass of 329 g of this
shredded cane is weighed out and transferred to a wet disintegrator (Fig 3.6). After adding
1 L of water, the wet disintegrator is operated for 8 minutes at a speed of 8000 rpm. After
the treatment, the fibres are normally well separated.
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