SOFTWOOD DISTILLATION 



229 



coal and the non-condensing gases, light oils, tar and pyroligneous acid. 

 The yields are generally about 7-10 gal. of refined wood turpentine, 

 i\ gal. of pine oil, 50 gal. of tar, and 800 to 900 Ib. of charcoal per cord of 

 fat pine weighing about 4000 Ib. Light oils and tar are very complex 

 and are usually separated into a variety of products depending upon the 

 current market conditions. Very little has been done commercially in 

 this field, however, and a great opportunity exists for further investi- 

 gation and research. The light oils are obtained in two fractions, the 

 one containing turpentine being condensed from a low temperature in 

 separate tanks. In some plants the volatile products are mixed in one 

 condenser. The pyroligneous acid contains the same ingredients as has 

 been described in the case of hardwoods, but in such small amounts that 

 it is not commercially profitable to refine it further, and it is usually 

 allowed to run to waste. The tar is refined to produce oils and a good 

 grade of retort tar may be sold in its original state. The turpentine is 

 of good color, but has a characteristic odor, and is considered somewhat 

 inferior to the spirits of turpentine secured by tapping the trees as 

 described in the Chapter on Naval Stores. 



It is impossible to state the average costs involved or to even approx- 

 imate an estimate of the number of men employed, kinds of equipment 

 used, etc., because each plant differs from the other and the standardiza- 

 tion in this industry is probably less than can be found in almost any 

 other. Lightwood is generally secured at about $3.00 to $4.75 per cord 

 f.o.b. plant. 



At one of the most important dry distillation plants in the Southeast 

 the following production was secured. This is based on a six-months' 

 run in which 8690 cords of longleaf pine were utilized. Each cord 

 (128 cu. ft.) of lightwood weighed between 3500 and 4000 Ib. 



PRODUCTION BY THE DRY DISTILLATION SYSTEM 



In addition to the above products, 39 bu. of charcoal were secured 

 from each cord, on an average. 



