DISTILLATION OF STUMPWOOD. 



27 



of unavoidable transfer losses. The mean of the two, therefore, 

 is used in calculating gallons a cord. 



Table 13. — Specimen log of a run of 150 pounds of Boise medium yellow-pine 



stumpioood. 



Time. 



Temper- 

 ature of 

 oil bath. 



Products obtained. 



Com- 

 bined oil 

 and wa- 

 ter. 



Remarks. 



Oil. 



Water. 



A. M. 

 8.25 



°C. 



Cc. 



Cc. 



Cc. 



Lighted gas, started pump, closed bottom coil. 



10.00 



223 

 238 

 250 

 260 

 261 

 256 



261 

 261 

 261 

 260 

 260 

 263 

 258 



281 

 298 

 310 

 319 

 322 

 327 

 336 

 340 

 344 

 346 

 342 

 342 

 342 









10.30 



410 

 540 

 500 

 495 

 430 



360 

 385 

 370 

 300 

 235 

 180 

 160 



135 

 165 

 170 

 380 

 230 



790 

 1,100 

 940 

 800 

 640 



485 

 530 

 570 

 590 

 590 

 570 

 560 



490 



560 



830 



1,550 



740 







11.00 







11.30 







12.00 







12.30 







P. M. 

 1.00 





of first turpentine. 



1.30 







2.00 







2.30 







3.00 







3.30 







4.00 







4.30 





opened bottom coil. 

 First of light oil. 



5.00 





5.30 







6.00 

 6.10 





Last light oil. 

 Heavy oil started. 



6.30 



3,050 



4,050 



2,050 



1,550 



1,100 



600 



240 



90 



7.00 







7.30 









8.00 









8.30 









9.00 









9.30 









10.00 







Shut down, drew pitch; drip 150 cc. heavy oil' by 

 next morning. 









Character of Changes Occurring During Distillation. 



Wood tissue is made up primarily of cellulose, which, built up 

 into cells and tissue, constitutes the structural element of plants, 

 and lignin, which occurs as an incrusting matter or coating on the 

 cell walls. In resinous wood there is a further deposit in the wood 

 tissue of oleoresin from which the turpentine and pine oils are ob- 

 tained when the wood is subjected to distillation at a relatively low 

 temperature. 



As previously explained, the nonvolatile substance remaining 

 when the volatile oils are distilled from the oleoresin is rosin, a sub- 

 stance largely composed of .abietic acid. Toward the end of the tur- 

 pentine stage of the distillation the contents of the retort may be 

 considered as made up principally of abietic acid, cellulose, and 

 ligninlike substances, all of which are composed of the elements 

 carbon, oxygen, and hydrogen. The molecules of these substances, 

 being comparatively large and complex, are readily broken down 

 by the application of heat into a series of simpler compounds, some 

 of which, reacting the one on the other, may form still other com- 



