12 PRODUCTS PROM WASTE RESINOUS WOODS. 



STEAMING DATA. 



It will be seen that when fresh chips were usea approximately 86 

 per cent of the total crude oils recovered were obtained in the first 

 30 minutes' relieving from the chips passing a one-fourth-inch mesh; 

 82 per cent from the chips passing between a one-fourth and a one- 

 inch mesh; while but 71 per cent were recovered from the chips 

 larger than one inch. The recovery in subsequent relievings falls off 

 rapidly from the fine chips, more slowly from the medium chips, and 

 still more slowly from the coarse chips. Not all the turpentine was 

 removed from the coarse chips. The total quantity of crude oils 

 recovered was least from the coarse and greatest from the medium 

 chips. There is no doubt, however, that the quantity of crude oils 

 in the chips was least in the fine and greatest in the coarse, since the 

 oils volatilize readily from the fine chips on exposure and very slowly 

 from the coarse chips. After cooking for pulp in Cook 8, in which 

 case the pressure was maintained for one hour at 75 pounds, 6 cc of 

 crude turpentine were recovered in 600 cc of water. From the pulp 

 of Cook 3, cooked under the same conditions, 3 additional cc of turpen- 

 tine were recovered in 800 cc of water. 



The quantity of crude oils actually recovered from the chipped 

 light wood under very favorable laboratory conditions was at the 

 rate of from 10 to 13.2 gallons per 4,000 pounds of wood containing 

 20 per cent of moisture, this percentage being an assumed quantity, 

 approximately the average percentage of moisture in air-dry, seasoned 

 wood. This yield is considerably below the yield generally claimed 

 by steam wood turpentine producers, but agrees quite closely with 

 the experimental work of the laboratory at steam plants, and also 

 with the census reports. Attention is called to the fact, however, 

 that some losses probably occurred in the transportation of the chips 

 from Florida to Washington, even though they were carefully wrapped 

 in paper and boxed to prevent such loss. The figures are certainly 

 not too high for the particular chips employed. 



Data of the same general nature were obtained in the distillation 

 of the steamed chips. A smaller percentage of the total oils recov- 

 ered was obtained in the first relieving, but this percentage was 

 greatest from the fine chips and least from the coarse. The recovery 

 decreased more rapidly from the fine and medium than from the 

 coarse chips. These figures also indicate the quantity of crude oils 

 left in 4,000 pounds of each size of chips steamed in stationary retorts. 

 This quantity is from 1 to 2 gallons in fine, 3i to 3| gallons in medium, 

 and practically 4 gallons in coarse chips. In other words, from 2 to 

 3.3 gallons of crude oils per cord remain in ordinary lightwood chips, 

 steamed in the usual way in upright retorts. 



It will be observed that there is some variation in the total time 

 of relieving and in the volume of water distilled among these experi- 



