240 RICHMOND. 



It will be noted that from 24 to 30 per cent of bleaching powder was required 

 to produce at best a poor white, that is, 12 to 15 kilos of bleaching powder of 

 the standard strength (35 per cent available chlorine) are required for 50 kilos 

 of unbleached pulp. This consumption is excessive, and it forms the greatest 

 objection to placing a bamboo pulp prepared in this way on the market. Esparto 

 requires 5 to 7.5 kilos and wood 6 to 12.5 kilos. The consumption of sulphur 

 is low and no account was taken of a certain percentage of recovery which is 

 always possible in practice. In sulphite wood pulp manufacture, 150 to 175 

 kilos of sulphur are usually required for the production of a ton of pulp, although 

 recent attempts at more efficient gas recovery have brought the sulphur con- 

 sumption per ton of pulp down to 115 kilos in some cases. 



The time required to produce an apparently well-cooked pulp was from six to 

 eight hours. This is in keeping with modern tendencies, and a rather weak 

 liquor (No. 3) produced as good a yield and a rather better bleaching pulp than 

 did a strong liquor (No. 2). 



Aside from the poor bleaching properties of bamboo sulphite fiber 

 prepared under the above conditions, there are other factors, both local 

 and general, which tend to preclude the use of the sulphite process ot: 

 treating bamboo at the present time. 



1. Bamboo fiber appears better suited for book printing and litho- 

 graphic papers than for wrapping or news printing paper. This being 

 the case, bulk, softness, and opacity, which are the chief features of soda 

 fiber, are what is desired. 



While sulphite fiber also enters into the composition of some grades of book 

 paper; this is probably due more to a question of the cost of production, or the 

 applicability of the raw material to the process, than to any inherent qualities 

 of the fiber itself for the particular purposes. Sulphite fiber produces the 

 stronger, harder, and more transparent papers demanded for tags, labels, wrap- 

 ping and news printing, and the cost of soda fiber is such that it is particularly 

 suited for blending with sulphite wood pulp, or with rags to produce the better 

 class of book printing and even certain commercial grades of writing papers. 



2. It is undoubtedly true that the sulphite process costs less than the 

 other for chemicals. Sulphur, at present quotations, can be converted 

 into sulphite liquor and thrown away after use at less expense than the 

 cost of soda actually consumed plus the cost of its recovery. However, 

 the local supplies of limestone are better adapted for making soda than 

 sulphite liquor. 



While a straight limestone can be, and is, used to some extent for 

 making sulphite liquor, a dolomite, that is, a stone carrying a high 

 percentage of magnesia, is much preferred. On the other hand, a good 

 lime for causticizing soda liquors should be as low in magnesia as pos- 

 sible. Thus far no dolomites have been found in the Philippines. 



The other chemicals, sulphur on the one hand and soda on the other, 

 used in the two processes, are not produced locally, hence would have to 

 be imported from the most favorable foreign source. 



