The objective of this study was to measure the anaerobic biodegradation of different types of paper products in
laboratory-scale landfill reactors. The study included (a) measurement of the loss of cellulose, hemicellulose,
organic carbon, and (b) measurement of the methane yields for each paper product. The test materials included
two samples each of newsprint (NP), copy paper (CP), andmagazine paper (MG), and one sample of diaper (DP).
The methane yields, carbon storage factors and the extent of cellulose and hemicellulose decomposition all consistently
show that papers made from mechanical pulps (e.g., NPs) are less degradable than those made from
chemical pulps where essentially all lignin was chemically removed (e.g., CPs). The diaper, which is not only
made from chemical pulp but also contains some gel and plastic, exhibited limited biodegradability. The extent
of biogenic carbon conversion varied from 21 to 96% among papers, which contrasts with the uniform assumption
of 50% by the Intergovernmental Panel on Climate Change (IPCC) for all degradable materials discarded in
landfills. Biochemical methane potential tests also showed that the solids to liquid ratio used in the test can
influence the results.