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GROUND WOOD PULP MILLS AND CHEMICAL FIBER MILLS 



(C) THE PLANT: — 



I. The chemical fiber plant requires an investment of about Jif 10,000 per ton of daily production. Unlike 

 a sawmill, a fiber plant cannot be shifted when the nearby supply of raw material is exhausted. 



II. A fiber plant must be located : - 



(a) Close to water; water is not so much used for motive power as for the washing of the fiber; 



(b) Close to cheap wood supply; wood must be plentiful and uniform, of a long, straight fiber, 

 readily interlacing and white; 



(c) Close to cheap coal, since the coal consumption per pound of fiber amounts to at least /i,; of 

 a pound of coal. So much coal is required for heating, drying, and bleaching, that all excepting 15 per 

 cent of the machinery should be driven free of charge. 



(D) PROCESS OF MANUFACTURE. The manufacture is either purely mechanical (ground wood 

 pulp) or also chemical. In the latter case, the soda process, the sulphite process, and the sulphate process 

 are distinguished. The electric process, though very promising, is still in early infancy. 



The mechanical process, applicable to spruce particularly, has consumed in the United States, in 1909, 

 altogether 1,246,121 cords out of a total quantity of 4,001,607 cords. 



The sulphite process was applied to 2,183,984 cords (mostly spruce, hemlock, balsam, fir). 



The soda process was applied to 571,502 cords (notably pine and hardwoods). 



The sulphate process is said to be particularly adapted to pine and larch. 



The principle of manufacture is: -Grinding and beating of wood in water until it forms a fluid pulp; 

 allowing water to run off through screens, leaving a matted stratum of wet fiber; bleaching; drying; pressing. 



I. Ground wood fiber: - 



(a) The log is cut (by a drop frame wood saw) into bolts one foot long and 5 inches thick. The 

 bark is removed, and the knots are usually bored out; 



(b) The bolts are fed into pockets and pressed against millstones of 26 inches face by 54 inches 



Overhead drop frame wood saw, made by M. Garland Co., Bay City, Mich. 



D is Ihe log lo be cut; C, Ihe cut piece of wood; A is Ihe drop saw frame; F, G, H, friction and 

 geared log chain drive, wliich can be slopped at »ny desired point and started at will. 



Vertical knot boring' machine. 



H. B. Smith Machine Co., 



Smithville, N.J. 



