solid waste 101

Paper is manufactured by mixing cellulose fibers, typically from wood, with water to make pulp, which is then dried in flat sheets. The longer the cellulose fibers, the stronger the paper. Wood from coniferous trees such as pines, spruces, firs, and hemlocks, has longer cellulose fibers than wood from other species, so is preferred for making paper. 

Waste paper and cardboard include office paper, newsprint, magazines, catalogs, paper bags, milk cartons, and corrugated boxes. This category has long constituted the greatest tonnage of municipal waste, with Environmental Protection Agency estimates increasing from 30 to 67 million tons nationwide between 1960 and 2018. 

Paper and cardboard can be readily recycled. However, each time paper is recycled the fibers become shorter, so recycled material is usually mixed with virgin pulp to maintain quality. Cardboard boxes, newspapers, toilet paper, and paper towels are common items manufactured from recycled paper.

Recycling rates for paper increased from less than 16.9% in 1960 to nearly 68.2% in 2018, while landfilling decreased from 83.1% to 25.6% over the same period. Incineration peaked at 11-12% during 1990-2000 and has been slightly above 6% in recent decades. 

The United States manufactures a lot of paper, generates a lot of wastepaper, and recycles a lot of paper. The Environmental Protection Agency estimated generation of 67.4 million tons of paper and paperboard waste in 2021, comprising approximately of which accounted for 23% percent of total municipal solid waste. Approximately 68% (46 million tons) was recycled, the highest rate of all materials. The rate of cardboard recycling was even more impressive at 91%.

Utilizing recycled material in the manufacture of paper and cardboard reduces water and air pollution and conserves energy, landfill space, and trees.