The utilization of CO2 in the pulp and paper industries is widespread. Its main uses include regulating and stabilizing pH, reducing CaCO3 dissolution, pulp-washing and soap acidulation. CO2 Solutions’ adaptable and efficient technology can help companies in this sector optimize their installations’ profitability.
CO2 Solutions’ carbon-capture process is even more advantageous, as it purifies 99.95% or more of the carbon dioxide recuperated, and can therefore be used worry-free in all types of applications appropriate to the processes of the pulp and paper industry.
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. This is largely due to the fact that using carbon gas greatly reduces their use of mineral acids, which are problematic operationally and for health reasons (corrosion, toxic vapour, potential flammability with certain chemical substances or combustible materials, dangerous manipulation, various irritants, and others). Using CO2 is more environmentally friendly and vastly simplifies pH regulation and stabilization, all in a benign process.
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 like lime sludge, green liquor lees and slaker grit, all of which are mainly constituted of CaCO3. As a result, operations are more efficient because less maintenance is required.
CO2 pulp-washing technology is widely used in fibre lines, as it offers several advantages: it provides better operability, lower steam consumption, reduced wash water volumes, lower volume use of foam inhibitors and pitch dispersants, and lower maintenance costs. The quality of the carbon dioxide captured and treated by CO2 Solutions’ innovative technology is perfectly suited to this application.
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, which also contribute to eliminating mineral deposits and increased efficiency.
A practical, profitable solution
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 – a solution that delivers benefits across the board.