Pulp and Paper
The utilization of CO2 in the pulp and paper industries is widespread and includes the following main uses:
Regulating and Stabilizing pH
Over the last few years, more and more pulp and paper mills have started to use CO2 to regulate and stabilize pH while reducing their use of problematic mineral acids.
Reducing CaCO3 Dissolution
Calcium carbonate (CaCO3) is present in most papermaking systems. CO2 can be added to the process to reduce its dissolution and eliminate mineral deposits.
CO2 pulp-washing technology is widely used in fibre lines, providing better operability, lower steam consumption, reduced wash water volumes, lower volume use of foam inhibitors and pitch dispersants, and lower maintenance costs.
CO2 for Soap Acidulation
Sulphuric acid consumption for soap acidulation in the production of crude tall oil (CTO) can be reduced by 30 to 50% by using CO2. This also allows the pulp mill to have better control of its sulphur-sodium balance.
Most pulp and paper producers currently obtain CO2 at a significant cost from external bulk gas suppliers. For these producers, CO2 Solutions’ process can be implemented to capture CO2 from black liquor boiler operations, where nil-value process heat can provide the energy for the CO2 recovery process. The result is lower CO2 acquisition costs, reduced dependence on external supply sources, and a lower carbon footprint of the pulp operation.