Paper and the greenhouse effect: a life style study

Environmental assessment of a product' over its entire life cycle can indicate the extent of the manufacturer's environmental responsibilities beyond the boundaries of its own facilities, and can identify appropriate management options. This thesis takes a life cycle approach to the assessment of the greenhouse gas emissions of paper, from forest through to landfill. An analytic framework is constructed to describe the complex paper production and consumption system, encompassing greenhouse gas fluxes from both the use of fossil carbon and from the cycle of organic material growth and decay. The greenhouse gas emissions from paper in Australia in 1994/95 were about 13.5 million tonnes of carbon dioxide equivalent, some 2.5% of the nation's total. More than half this amount consisted of methane emissions from paper decaying in landfills. Fossil fuel and electricity use in pulping and paper making were responsible for 42% of all emissions, and transport and other system components were less important. In all, fossil carbon use formed 62% of the total, since landfill emissions were partially offset by a net uptake of carbon dioxide in the organic material cycle. The effects of various management and assessment options on the greenhouse impact of a tonne of paper over its whole life cycle are modelled. In current circumstances, emissions are typically about 5.0t of carbon dioxide equivalent per tonne of paper. Effective abatement options for the Australian pulp and paper industry include using alternatives to mechanical pulping and manufacturing in States which produce less emission-intensive electricity. All waste management options which keep paper out of landfills significantly reduce greenhouse emissions but incineration with energy recovery is most effective. Recycling is also beneficial, and is of particular interest from a management perspective because it is controlled by the pulp and paper industry. This value of recycling is only revealed through whole-of-life assessment as undertaken in this thesis. The comparative significance of the emissions from fossil carbon and the organic material cycle is dependent on the relative warming effect of carbon dioxide and methane, which varies widely with the assessment time frame. A 100 year planning horizon is generally considered optimal and all the above results are determined on this basis. Over a 20 year assessment period the importance of the organic material cycle is paramount but over 500 years emissions from use of fossil carbon dominate