Millions to gain from tall oil
14 Swedish kraft pulp mills have been discussing how tall oil extraction during the pulping process could be made more profitable. There is a lot of money to be saved by doing it the right way.
Swedish kraft pulp mills have been discussing and comparing their processes in a broad-based partnership between various operators, in which they have all shared their problems and improvement measures. And there is a lot of money to be saved.
The main focus of a recently completed project was to extract more tall oil in order to replace fossil fuels in biodiesel, or to extract green chemicals. According to Håkan Enwall, initiator of the project that aims to optimize the tall oil extraction and quality of the tall oil, the recovery boilers at pulp mills play a crucial role.
“Restrictions in recovery boilers are not unusual. If the dry solid content of the liquor to be digested in the recovery boiler is too low – or if the evaporation slows down so that not enough liquor is produced, the effect is equal to a production restriction.”
“If you account for a 2% production restriction, a mill with an annual capacity of 400,000 tons can save millions,” says Håkan Enwall to Nordic Paper Journal & BioBusiness.
In addition to tall oil, the liquor, soap and splitting liquid from various mills have been analyzed to acquire more knowledge of the processes and their operating economies.
“The tall oil process affects other processes. Splitting liquid is returned to the chemical cycle and may lead to a production loss if it’s not used correctly.
The performance of the recovery boiler and the evaporation facility will be impacted, and that could cost a lot of money.