At Domtar, we work hard to ensure that we use every part of every tree that we harvest. That includes byproducts or extractives from the kraft pulping process, such as turpentine and lignin. One such material is tall oil, which we sell to companies that refine it for use in a variety of applications.
“Tall oil comes mainly from pine trees, and it contains rosin, resin acids, fatty acids, fatty alcohols and some sterols,” says Dale Mitchell, director of business development for Domtar. “We’ve been making it for as long as we’ve had our pulp mills.”
Tall Oil Applications
Tall oil, also known as crude tall oil, comes from a material known as black liquor soap. The soap floats to the top of our black liquor tanks, and it can be sold as-is from our Ashdown, Plymouth and Marlboro mills or acidulated into tall oil at our Nekoosa and Espanola mills. Refiners purchase these products and further refine and separate them for use in industrial products, such as adhesives, inks, detergents and emulsifiers. Tall oil derivatives can also find their way into some consumer products and, interestingly, the sizing used in the paper manufacturing process.
Stan Wheeler, who spent more than 30 years working in the extractives space and now consults with Domtar, compares tall oil to crude oil. “Like petroleum-based crude oil, once tall oil leaves the mill, it’s refined or distilled into its various parts. But instead of getting gasoline and diesel fuel, for example, you get gum rosin, pitch, fatty acids and more, all of which are useful for a wide range of industrial applications,” he says. “A common product that consumers are familiar with is a fire-starter log, which is full of tall oil pitch because it burns slowly. But it also shows up in asphalt, lubricants, tires, soaps, industrial coatings and so much more.”
Tall Oil Innovation
Tall oil may be a staple of Domtar’s extractives business, but that doesn’t mean the market for it is stagnant. “It’s a material that’s been around for many, many years, but over the past few years there’s been a lot of interest in using it for new products, particularly in the biofuel industry,” says Mitchell. “As people continue looking for better, more sustainable ways to generate energy, we’re seeing a growing demand for tall oil, which can be used as a raw material for biodiesel.”
Wheeler finds the surge of innovation exciting. “What’s more green, more sustainable and more renewable than a tree? In many ways, tall oil is the original green chemical,” he says. “There’s a limited supply of tall oil, so it’s not likely to replace other biodiesel feedstocks, but it’s interesting to see how companies continue to innovate with this and many other tree-based materials. They’re making great strides in creating renewable, sustainable, green products from byproducts of the papermaking process so that nothing goes to waste.”
Learn more about our extractives business with this video, and read about the other ways we use every part of the tree: