Why Does Pulp Pollution Matter?
Pulp and paper is the third largest industrial polluter to air, water, and land in both Canada and the United States, and releases well over a hundred million kg of toxic pollution each year (National Pollutant Release Inventory, 1996). Making paper also consumes vast quantities of trees. But paper is an essential product, and we need to continue to look for improvements in pulp technology, new sources of fibre, and new technologies to get more out of the resources we use, and to avoid their use in the first place.
Kraft pulping, also known as sulphate, or chemical pulping, uses sulphur to get fibre out of trees. The sulphur chemicals account for the rotten egg smell of many pulp mills. Kraft pulping uses less than 50% of the tree. The rest ends up as sludge which is burned, spread on land or landfilled. A bonus of kraft pulping is that the chemicals can be recycled and re-used in the mill. Another is that kraft fibre is exceptionally strong (“kraft” means “strong” in German). Magazines, printing and graphics papers, grocery bags and corrugated packaging are examples of products made with kraft pulp. Kraft pulp is usually dark and is often bleached with chlorine compounds.
Pulp mills are voracious water users. Their consumption of fresh water can seriously harm habitat near mills, reduce water levels necessary for fish, and alter water temperature, a critical environmental factor for fish. Mill owners say they are unable to institute water conservation and recycling because the concentrated effluent would kill fish (British Columbia COFI Pollution Prevention Workshop, June 1997, Environment Canada PPER Consultations, June 2000).
In British Columbia, Canada, 17 kraft mills discharge about 641 billion litres (141 billion gallons) of liquid effluent each year (Environment Canada, Environmental Effects Monitoring Report). While this liquid effluent is much less toxic than it was 10 years ago, “accidents” still kill test fish at one or two British Columbia (BC) mills nearly every month. Even after the pollution control investments of the mid-1990s, the Fraser River, BC’s largest watershed and one of the best wild salmon rivers in the world, is still 1% pulp mill effluent for 600 km during winter low water!
Mill waste water continues to wreak havoc on surrounding ecosystems. In laboratory tests, mill effluent causes reproductive impairment in zooplankton, invertebrates (both these are food for fish), and shellfish (Environment Canada, Environmental Effects Monitoring Report, Cycle One). Other studies show genetic damage and immune system reactions in fish (Easton et al. 1997, Genetic Toxicity of Pulp Mill Effluent on Juvenile Chinook Salmon (Onchorhynchus shawytscha) Using Flow Cytometry, Elsevier Science Ltd., Vol. 35, #2-3).
Mechanical pulping mills physically shred trees into pulp with grind stones and/or heat. Mechanical processes use about 90% of the tree. Unfortunately, mechanical pulp has weaker fibres, tends to discolour over time, and the process uses a lot of water and energy. Mechanical pulp is commonly used for newspapers and is often bleached with hydrogen peroxide or other chlorine-free alternatives.
“In British Columbia, Canada, 17 kraft mills discharge about 641 billion litres (141 billion gallons) of liquid effluent each year (Environment Canada, Environmental Effects Monitoring Report). While this liquid effluent is much less toxic than it was 10 years ago”.
Air pollution from pulp mills is not well studied. Mills should be, but usually are not, monitored for a range of air emissions, such as particulate matter, carbon dioxide, sulphur dioxide, hydrogen sulphide, volatile organic compounds, chlorine, chloroform, and chlorine dioxide. Incomplete data from British Columbia’s Environment Ministry indicates that in 1997, mills in this Canadian province emitted 17,000 tonnes of particulates and 2.7 million tonnes of carbon dioxide, plus other unreported emissions.
Air discharges from pulp mills contain hormone-disrupting and carcinogenic chemicals, such as chlorinated phenols, polycyclic aromatic hydrocarbons (PAHs), and VOCs. British Columbia’s coastal pulp mills are the largest provincial source of airborne dioxins and furans, which are among the most toxic substances known.
Sludge, the Triple Threat
Each Canadian mill produces an average 40 oven-dry tonnes of sludge per day, which is de-watered and then either land filled or burned. Each year, mills in the province of British Columbia create over half a million tonnes of sludge from secondary treatment plants, power boiler ash, chemical processing, waste fibre, sawmills, and other sources. Because of the different disposal methods, sludge pollutes soil, air, and water.
Many mills in Canada currently burn their sludge, but are eager to spread it on forests, parks, and farm lands as “fertilizer.” Many questions remain about what is in sludge remain and rigorous testing would be required before permitting this practice. In the meantime citizens themselves are forced to deal with the issues and become Sludge Busters when there is pulp mill sludge being spread near them.
Pulp & Paper Publications
Making Paper As If The Earth Matters
This illustrated booklet, Making Paper As If The Earth Matters, started off as a set of displays for the general public on pulp production, fibres, and clean production. Then it evolved into a tabloid newspaper, and can be downloaded as a pdf file HERE. To download a version for print reproduction, CLICK HERE . (9 MB).
The Pulp Pollution Primer
The Pulp Pollution Primer, published in October 1999, explains the basics of pulp pollution, our vision for a cleaner future and explores ways to get there. To view a pdf version of the Primer CLICK HERE (384 kb).
“There are about 500 kraft mills, and many thousands of other types of pulp and paper mills, in the world. Primary concerns include the use of chlorine-based bleaches and resultant toxic emissions to air, water, and soil. With global annual growth forecast at 2.5%, the industry and its negative impacts could double by 2025”.
The Production of Bleached Kraft Pulp
by Lauren Blum, Environmental Defence Fund, 1996. A detailed explanation of the kraft pulping and bleaching process.
The US Paper Industry Association Council (PIAC) (35 allied paper product associations representing the major manufacturers and providers of paper based communications and packaging products) has a basic video, Paper Recycling from Curb to Consumer, on their website at www.paperrecycles.org
A virtual mill tour, explaining the basics of kraft and thermomechanical pulping, is available at the Howe Sound Pulp and Paper Limited web site – www.howesoundpp.com (now defunct).
See what BC salmon stewards say about threats to salmon and their genetic structure, and how paper is made at www.salmonopolis.ca (expired link).