ETHYL ALCOHOL FROM WOOD WASTE. 3 



AMOUNT OF WOOD WASTE AVAILABLE. 



The amount of wood waste produced by converting a tree or a 

 sawlog into lumber is, of course, variable and depends upon the diam- 

 eter of the tree, the quality of the timber, and the efficiency and 

 equipment of the sawmill. The following tabulation shows that more 

 than half of the cubic contents of the tree is wasted : 



Per cent. 

 Entire tree 100 



Stump 2 



Top 18 



Sawdust 12 



Bark 10 



Per cent. 

 Slabs 8 



Edgings 8 



Shavings 4 



62 



This includes limbs, top, and stump — the parts of the tree left in 

 the woods — in addition to the waste at the mill or factory. The mill 

 waste, particularly the part available without extra transportation 

 charges, is of great interest in connection with the manufacture of 

 ethyl alcohol. 



The annual cut of lumber in the United States for the five or six 

 years preceding the World War was approximately 40,000,000,000 

 feet board measure. 2 The mill waste from this cut has been estimated 

 by Margolin 3 as follows : 



Per cent. 

 100 



Bark 13 



Sawdust 13. 5 



Edgings and trimmings. . . i 8.7 



Slabs. .', 8. 7 



Careless manufacturing and accidents 



Loss in cutting to standard widths and lengths . 



3.5 

 1.7 



Total waste 49. 1 



Lumber 50. 9 



For each thousand board feet of lumber produced from sawlogs 

 (which is equivalent to 83.3 cubic feet of solid wood) there is, according 

 to the above table, 80 cubic feet of waste, distributed as follows: 



Cu. ft. 



Bark 21. 3 



Sawdust 22 



Edgings and trimmings 14. 2 



Slabs 14. 2 



Careless manufacturing and accidents 5.6 



Loss in cutting to standards 2.7 



Total. 



2 The Lumber Industry, Part IV, Bureau of Corporations, TJ. S. Dept. of Commerce; The Production 

 of Lumber in 1913, Bulletin No. 232, U. S. Dept. of Agriculture. 



3 Report of the National Conservation Commission, vol. 2. 



