l8 FOREST PRODUCTS LABORATORY 



PULP AND PAPER. 



The constantly decreasing supply of suitable pulp woods and the 

 ever-increasing demand for paper of all kinds, especially newsprint 

 paper, have combined to produce so serious a situation that investiga- 

 tions into methods of conserving the supply of pulp wood and increasing 

 the production of paper are of paramount importance. 



PROCESSES OF PULP AND PAPER MAKING. 



The Laboratory is conducting experiments on methods of making 

 wood pulp and has already developed several important improvements 

 in the standard chemical processes. 



A very important field of research lies in determining the suitability 

 of various little-used woods as substitutes for those most commonly used. 

 Practically all available species which give promise of suitability are 

 being investigated, and proper methods of grinding or cooking of most 

 of the important ones have already been worked out. 



UTILIZATION OF WASTE- 



Studies of waste utilization in the pulp and paper industry have been 

 in progress for some time along a number of distinct lines. For example, 

 feasible methods of turning sawmill waste, such as slabs, into pulp have 

 been determined. The use of a certain percentage of spent tanbark in 

 the manufacture of roofing felts has been investigated and a method 

 developed whereby what was formerly a waste of the tanning industry 

 is now in profitable commercial use. The possibility of using hemlock- 

 bark waste for tannin has also been demonstrated. 



A commercially feasible method of recovering both the paraffin and 

 the fiber from waxed paper trimmings has been developed. Studies of 

 the wastes incident to the pulp industries, such as sulphite waste liquors 

 and soda liquors, in which are now carried off approximately half of the 

 wood that enters into the digesters, are to be undertaken intensively as 



