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1080 
PRELIMINARY PREPARATION OF BAMBOO FOR DIGESTION 
EXPERIMENTS. 
At first the outer, silicated rind and the nodes or joints of mature culms 
were digested separately, but it was found that the latter yielded to 
alkaline treatment with the formation of very little shive, but with a less 
cellulose content than when internodes alone were used. The yield of pulp 
on the nodes and rind, respectively, was 35 per cent, as compared with one 
of 42 per cent on internode wood alone, under the same conditions. This 
deficiency is fully accounted for by the larger amount of mineral matter 
deposited in the joints and on the exterior surfaces of the mature bamboo 
stems. 
All experiments in this direction showed that in practice the joints or 
nodes, if well crushed, would offer no resistance to caustic soda liquors 
and that it would not be necessary or even advantageous to effect any 
preliminary sorting between the different portions of the stem, hence in 
the recorded experiments no separation was practiced. Bamboo pulp, 
similarly to straw and grass fibers, shows a tendency to roll up into little 
balls under slow motion, so that rotary digesters would probably prove 
unsuited to this raw material. 
EXPERIMENTAL PART. 
All of the digestion and bleaching experiments tabulated below were 
made on 454 gram lots (1 pound) of air-dried material. The bamboo 
chips or sticks were packed into an upright digester, variable quantities 
of caustic soda liquor, in all cases sufficient to cover the chips, were added, 
and the heating was done by direct flame. 
TABLE II. 
STRUCTURAL BAMBOO (Bambusa blumeana). 
* 
Experiments. 
Conditions of digestion. an wie Bieta ; 
16 It. III. IV: v. AA 
Strength of liquor ____---- per cent__ 10 10 74 7 3} 6} 
Amount of caustic soda calculated 
on the weight of the material 
ISON t oe eee Son ss per cent__ 225 20 17} 15 20 12} 
PEG OR CEE ons anne dace hours__ 9 5 5 5 5 5 
Pressures employed___atmospheres__ 6 5-6 8 6-7 8 6-7 
Yield of pulp: 
Unbleached_-_____----.. per cent__ 41.75 42 42. 55 41 42.7 43.1 
Bienenee Was esto Oe ile 40.2 40,6 tae 28. $9. 4 | Sascneae q 
Amount of bleaching powder con- 
ol | See ae! per cent__ 22. 85 1:7 23.9 Tmecesene 24.8: | ae 
Loss of weight in bleaching__.do____|_----_---- 4.4 46 ha 7.9 
SA ete Hu co en igktdnds secRisad Yellow:.| sGPeams | 5.séc.c- cease eee Poor. «ga geae 
white. 
