By-Products of Softwood Pulping

The heartwood of most species is richer in ehemical extractives than is the sapwood. Pines eontain mainly resin acids and triglycerides. Turpentine is obtained early in the pulping sehedule by flashing steam and volatile chemicals from the digester, the turpentine separating from the cooled water eondensate. The principal constituents of pine turpentine are a- and 3-pinenes. 

Tall oil is obtained from the concentrated black liquor. The soap on the surface of the blaek liquor eoncentrate is skimmed off, and after acidification yields a mixture of resin aeids, fatty acids and neutral eomponents. 

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