The Chempolis process is also based on using formic and acetic acid (Rousu & Rousu 2000, Rousu et al. 2003, Anttila et al. 2006) as cooking chemicals to produce pulp, biochemicals and biofuels from non-wood raw materials. Formic acid is the main component in cooking liquor. After cooking, the pulp is washed and pressed in several stages with formic acid. The last washing stage is performed at a high pulp consistency with performic acid. Then, the pulp is bleached with alkaline peroxide. Spent cooking liquor can be evaporated to 90% dry solids and incinerated. The evaporation.
