Removing Emissions with Pulp and Paper Mills
As a BECCS project developer, Biorecro partners with industrial facilities to deploy BECCS operations at the facility site. Potential facilities fit for BECCS (Bioenergy with Carbon Capture & Storage) include but are not limited to, combined heat and power (CHP) plants, bioethanol plants, biogas plants, or pulp and paper mills. In this article we breakdown the climate mitigation potential of BECCS implementation at pulp & paper mills.
The paper industry has existed for centuries, providing essential products that are used in day-to-day life. The biggest players of industry are mostly located in North America, Northern Europe, and in East Asia. Notable names include International Paper, WestRock, Smurfit Kappa Group, UPM, Stora Enso, Oji Holdings Corporation, and Nine Dragons Paper Holdings.
Because pulp & paper products are sourced from biomass within the Earth’s carbon cycle, their manufacturing processes can be converted into a powerful climate mitigation tool. Today, many pulp and paper mills are looking to take sustainability to the next level by incorporating BECCS . Doing so would reduce emissions and convert the business into net-negative operation, with the opportunity for additional revenue from the sale of carbon removal.
What is Pulp Used For?
Tree pulp is the fibrous material found in wood and it’s processed through a combination of chemicals and separation of the adhesives and water also found within wood. Pulp is a versatile ingredient used to produce cardboard, tissue, book pages, baby wipes, and other everyday products.
Companies often rely on the acacia and eucalyptus tree species for pulp and bring them to mills in the form of logs, wood chips, and sawdust. Depending on the final product, the way in which the wood is processed will vary. However, no matter the process, facilities will use the byproducts that result from papermarking as a fuel source to provide energy. This ensures nothing goes to waste and keeps operations as sustainable as possible.
The Process of Papermaking
Papermaking has three main steps in its processing.
1. Pulping: Trees are brought to a debarking machine since bark can’t be used to produce paper. Bark and other waste byproducts of the tree will instead be used as fuel in a combustion process to produce electricity.This biogenic CO2 is then released back into the atmosphere through facility smoke stacks.
This is where the potential for BECCS implementation exists – more on that later in the article.
After bark removal, logs are cut into smaller pieces and cooked in a machine called a digester. This dissolves the lignin fiber, an adhesive substance, that’s within wood. Once the lignin is removed, pulp is whitened and dried.
2. Papermaking: The pulp is then mixed with water and chemicals, causing the pulp’s fibers to spread and form sheets. Afterwards, about half of the water content in the sheets is squeezed out by machine. The paper is then dried at around 100° C to complete the drying process.
3. Finishing: The paper is coated with a compound for quality improvement followed by another drying process to form a giant roll of paper, from there the cut paper is tailored to its final product purpose.
Energy Production
The pulp and paper industry relies on both thermal and electrical energy. The pumps and fans in a mill use electrical energy, while the digesters and drying processes use thermal energy in the form of steam.
Pulp and paper mills have the ability to produce their own energy from byproducts and in many cases this energy production allows mills to be self-sustaining. In the United States alone, over half of the energy at pulp and paper mills is self-generated. The energy is garnered from burning the wood waste byproducts that are unusable in the manufacturing process and would otherwise have gone to waste.
When burned, the byproducts create steam to power paper machines at the mill, run turbines to create electricity which can help power the mills and even nearby communities. Depending on production, mills can generate nearly as much renewable energy it consumes during its industrial process.
The Next Hub for Carbon Removal
Using the byproducts in this manner ensures every part of the tree is used. This is where BECCS can be implemented to help the milling process become more sustainable and efficient. After combustion is used to turn byproducts into electricity, the CO2 emissions released during the process can be captured and stored utilizing BECCS technology.
Instead of releasing biogenic CO2 into the atmosphere, those waste emissions are removed and sequestered underground permanently. Not only does this make the entire process more sustainable and efficient, it also provides additional revenue streams to these facilities through the sale of carbon removal on the voluntary and regulated carbon markets.
In Europe there were over 700 pulp and paper mills reported in 2019. Worldwide there are roughly 10,000 pulp and paper mills in operation. The industry had a global value of 351.53 billion U.S. dollars in 2021 and has grown since then. The scope of the pulp and paper industry leaves an equally large potential for carbon removal. The average facility may have a carbon removal potential between 400,000-1,000,000 tonnes/year with BECCS technology. As a rough estimate, the lower end of this range multiplied by the 10,000 existing pulp and paper mills could yield at least 4B tonnes/year globally.
Logistics Chain with BECCS
Once byproducts are separated from tree pulp at mills they are combusted to provide power for the facility. This becomes the first step within the BECCS logistics chain. When the waste biomass is combusted, BECCS technology captures the carbon dioxide from the flue gas stream. After combustion, carbon dioxide is pressurized to convert it into a supercritical fluid. As a supercritical fluid, carbon dioxide takes up less space for easy transportation and allows for a greater amount to be sequestered underground.
After separating carbon dioxide from the combustion process, it’s brought from the pulp and paper mill to the sequestration site. This can be done through a combination of pipelines, ships, trucks, or trains to a secure geologic storage site.
At the final storage site, the carbon dioxide is injected thousands of meters underground into a geologic reservoir. The porosity and permeability of the reservoirs allow carbon dioxide to integrate without issue. Once underground, carbon dioxide begins to mineralize in the reservoir where it will remain permanently.
Utilizing pulp and paper mills for carbon removal will create a more sustainable industry and introduce a new avenue of profit through the sale of carbon credits. The pulp and paper industry is just one of many markets that can benefit from the implementation of carbon removal technologies like BECCS.
