The paper industry uses both fresh and recovered fibers as raw materials. Fresh fibers, or wood, are sourced from natural forests and tree plantations. Fresh material is broken down into wood chips and converted to pulp in mechanical or chemical processes. Fiber can also be recovered as by-products in industrial processes or after consumer use. By-products, known as post-industrial, pre-consumer materials, include sawmill residue, residue from the making of wood pulp, and trees that are too small or crooked to be cut into lumber. Post-consumer materials are collected from end consumers after paper-based products are discarded. For an overview of terms and concepts used in this chapter, see also Box 17: Terminology and Definitions.
The recovery and recycling process
Paper recycling rates are increasing significantly in many countries (Figure 12). This increase reflects growing demand for recycled fiber as governments and other organizations continue to establish recycled content requirements, and greater consumer demand for recycled products.
However, while certain types of pre-consumer materials can be recovered efficiently, recovering post-consumer material for use in recycled paper products is more complex. A wide range of actors are involved in the post-consumer paper recovery and recycling process: the paper industry, local government institutions in charge of solid waste and wastewater effluent, third-party waste management companies, as well as private and industry consumers. In some regions, demand for recovered fibers exceeds the amount that can be collected.
Because wood fibers cannot be recycled indefinitely, a constant flow of fresh fiber into the fiber network is needed. Depending on the origin of the fresh fiber and the type of products, fiber is typically degraded and unusable after five to seven cycles. Thus, fresh fiber is constantly needed to compensate for the retirement of degraded fiber, archival storage of paper, and loss of fiber through normal use and disposal of certain non-recyclable paper products, such as personal care and tissue products.
In addition, varying amounts of fresh fibers are required to make certain products, and for some products, recycled fiber cannot be used at all. The amount of recycled fiber used depends on economic factors (cost and availability of recovered fiber, cost of fresh fiber, and cost of processing) as well as quality considerations in the final product. For instance, newsprint and cardboard can contain a much higher amount of recycled fiber than archival paper (NCASI 2014).
Using recycled fibers to produce paper reduces pressure on forest areas because less fresh content is needed per unit of paper produced. However, the recovery and recycling process is resource and energy intensive. The decision about whether to use recovered fibers and what percentage to use should be made after analyzing the kind of fibers needed for the end product, the availability of fresh and recycled fibers, and the environmental implications of both types of fiber for a specific product supply chain.
Additionally, it is important to consider not only fiber sources, but the holistic environmental impact of both fresh and recycled fibers. Wood and paper-based products have environmental impacts at every stage of their life cycle. Therefore, the environmental impacts of fiber recovery, recycling and reuse should be considered from a life cycle assessment (LCA) perspective, taking into account energy and resource use, and by-products such as solid waste and wastewater effluent.
It is difficult to directly compare energy consumed by using recycled fibers with energy consumed by using new fibers. The energy input depends on many factors, such as distance between fiber source and processing facility, condition of the recovered paper, and the characteristics of the end product. Indirect impacts may also be relevant. For instance, recycling reduces the demand for fresh fiber, which may reduce harvesting pressure on forest areas. In some circumstances, reduced harvesting could also increase pressures to convert the land to a different use.
Figure 13 highlights potential positive and negative impacts of using fresh fibers and recycled fibers. However, the specific impact of using fresh or recycled fibers should be considered on a case-by-case basis. The underlying assumptions and the relative importance assigned to the range of inputs and outputs also significantly influence the outcome of the LCA. The resources recommended at the end of this chapter provide more information about how to analyze the environmental impacts of recycling.
Use of alternative fibers
In addition to fresh and recycled wood fibers, non-wood fibers or agricultural residues can be used in paper-making. These alternative fibers include flax, kenaf, hemp, bamboo, rye, wheat straw, and fiber from sugar cane (bagasse).
Alternative fibers and agricultural residues hold some advantages for paper-making:
The demand for wood fibers from unsustainable sources is reduced, as is the pressure on forests for fiber production and the risk of companies procuring fresh fiber from illegal sources or high-risk forest areas. Using by-products from annual agricultural crops to produce paper and paper products can reduce negative environmental impacts caused by field-burning or landfilling of crop residuals.
Rural economies and employment can benefit. In India and China, for instance, non-wood fibers play an important role for livelihoods in some areas.
However, alternative fibers have so far failed to attract a strong interest from major industrial paper makers for at least four reasons:
Certain alternative fibers are not available throughout the year, meaning storage capacity would be needed to feed mills year-round.
The supply system for wood fibers is well established, whereas a supply system for alternative fibers must be designed and constructed, and offers less predictability and control.
Some alternative fibers may not meet the performance requirements for certain products (e.g., rice straw for making newsprint).
The high silica content in some alternative fibers (e.g., straw) continues to cause processing problems.
Key questions to consider when requesting paper made from alternative fibers include:
Will the use of alternative fibers allow forests to be conserved because fiber can be sourced from faster-growing alternative crops?
Will environmental advantages that may be present with small-scale alternative fiber growth and use for paper production persist when the production is scaled up, or does it result in more negative environmental impacts? (Consider water use, chemical inputs, energy requirements, climate effects, reduced biodiversity etc.).
Is there a risk that existing forest land will be converted to agriculture to increase supply of alternative fibers?
What effects, both positive and negative, would switching to alternative fibers have on local communities and indigenous peoples?
Factors to consider regarding use of fresh and recycled fiber
For most products, there is a maximum amount of recycled fiber that can be used without compromising product quality. The optimal amount of recycled content is not necessarily the same as the maximum amount that could be used. The optimal amount of recycled fiber is determined by product specifications, consumer preference, availability and cost of recovered fibers of the quality needed, and government or industry standards. Decisions about the optimal recycled fiber content should take into account the views and interests of consumers, company management, local and national government and regulatory authorities, and recovered fiber suppliers.
Fiber characteristics depend on the type of tree and the growing conditions (Paper on Web 2014). When fibers from recovered paper are mechanically re-pulped, the structure and texture of the end product are affected.
Objectives related to recycling or the use of recovered fibers can be included in a sustainable procurement policy based on a supply chain analysis of environmental benefits. A company may also set targets for increasing the relative proportion of recycled and fresh fiber content in its products. A procurement policy may also incorporate supportive measures for helping local governments to collect recycled fibers in sufficient amounts to meet demand.
_________________________ 1 The same study examined production of newsprint in Canada and the US. The result suggests that production of newsprint would have to cease after three and a half months if only recovered fiber were used.