PULP, PAPER, AND BY-PRODUCTS 



Mill after mill has been installing the necessary tur- 

 pentine recovery equipment. Once in, even if the price 

 of turpentine toboggans, this apparatus will not be 

 scrapped. Sulfate turpentine is low-grade, but it is a 

 workable raw material for chemical processing and the 

 naval stores plants have been delighted to have it 

 pumped in by pipe from neighboring paper mills and 

 to buy all they could for tankcar shipments. The higher 

 the price of gum turpentine is held up, the more eagerly 

 will the chemical plants grab this by-product material. 



The distinctive waste of the kraft paper mills is "black 

 liquor," a most unprepossessing goo which contains just 

 about all of that waste half of the wood which they take 

 such pains and expense to remove from the cellulose. 

 Most of it is evaporated and burned under the boilers. 

 If, however, it is allowed to stand a few hours, a soapy- 

 oily-frothy curd rises to the top, a fitting cream to be 

 skimmed off this witches' brew of waste. This is tall-oil 

 skimmings or black liquor soap, a mixture of the oils 

 and rosins in the pine wood, saponified by the alkali in 

 the pulp-cooking process. 



Tall-oil skimmings are crude stuff, indeed, but they 

 contain a mixture of fatty and rosin acids, valuable in 

 making soap, cleaning compounds, paints, oil and as- 

 phalt emulsions, disinfectants, and lubricants. There is 

 plenty of this waste at the mills: one hundred and 

 twenty pounds of skimmings from each ton of wood 



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