IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group III: Mitigation of Climate Change

7.4.6 Pulp and paper

The pulp and paper industry is a highly diverse and increasing global industry. In 2003, developing countries produced 26% of paper and paperboard and 29% of global wood products; 31% of paper and paperboard output was traded internationally (FAOSTAT, 2006). Direct emissions from the pulp, paper, paperboard and wood products industries are estimated to be 264 MtCO2/yr (72 MtC/yr) (Miner and Lucier, 2004). The industry’s indirect emissions from purchased electricity are less certain, but are estimated to be 130 to 180 MtCO2/yr (35 to 50 MtC/yr) (WBCSD, 2005). Mitigation options

Use of biomass fuels: The pulp and paper industry is more reliant on biomass fuels than any other industry. In developed countries biomass provides 64% of the fuels used by wood products facilities and 49% of the fuel used by pulp, paper and paperboard mills (WBCSD, 2005). Most of the biomass fuel used in the pulp and paper industry is spent pulping liquor, which contains dissolved lignin and other materials from the wood that are not used in paper production. The primary biomass fuel in the wood-products sector is manufacturing residuals that are not suitable for use as byproducts.

Use of combined heat and power: In 2002, the pulp and paper industry used cogeneration to produce 40% of its electricity requirements in the USA (US DOE, 2002) and over 30% in the EU (CEPI, 2001), and that use continues to grow.

Black liquor gasification: Black liquor is the residue from chemical processing to produce wood pulp for papermaking. It contains a significant amount of biomass and is currently being burned as a biomass fuel. R&D is underway on gasification of this material to increase the efficiency of energy recovery. Gasification could also create the potential to produce synfuels and apply CCS technology. IEA (2006a) estimates a 10 to 30 MtCO2 (2.7 to 8.1 MtC) mitigation potential for this technology in 2030. While gasification would increase the energy efficiency of pulp and paper plants, the industry as a whole would not become a net exporter of biomass energy (Farahani et al., 2004).

Recycling: Recovery rates for waste paper (defined as the percentage of domestic consumption that is collected for reuse) in developed countries are typically at least 50% and are over 65% in Japan and parts of Europe (WBCSD, 2005). Globally, the utilization rate (defined as the fraction of fibre feedstock supplied by recovered fibre) was about 44% in 2004 (IEA, 2006a). The impact of this recycling is complex, affecting the emissions profile of paper plants, forests and landfills. A number of studies examine the impacts of recycling on life-cycle GHG emissions (Pickens et al., 2002, Bystrom and Lonnstedt, 1997). These and other studies vary in terms of boundary conditions and assumptions about end-of-life management, and none attempt to examine potential indirect impacts of recycling on market-based decisions to leave land in forest rather than convert it to other uses. Although most (but not all) of these studies find that paper recycling reduces life-cycle emissions of GHG compared to other means of managing used paper, the analyses are dependent on study boundary conditions and site-specific factors and it is not yet possible to develop reliable estimates of the global mitigation potential related to recycling. However, both the USA (US EPA, 2002) and EU (EC, 2004) identify paper recycling as a GHG emissions reduction option.