A BRIEF HISTORY OF PAPER
Many people assume that tree-free and recycled paper are new environmental
"fads." But paper has only been made from wood pulp since the 1850s.
The first recycled paper dates back almost 2,000 years to when a
Chinese court official, Ts'ai Lun, developed paper made from rags,
old fishing nets, hemp and China grass for the Chinese Royal Court
in the second century. (Clearly, this was tree-free and chlorine-free
paper as well!)
By the fifth century, the Chinese had invented printing; by the
eighth century the art of making paper spread to the Arab world.
The Arabs improved the art by making paper from linen and soon paper
usage spread through the Middle East and into Spain. By the eleventh
century, Japanese papermakers were using wastepaper to produce new
paper. Old documents and papers were repulped and made into new
papers to be sold in paper shops.
European papermaking didn't blossom until the 15th century. When
Gutenberg produced his first Bible in 1456, most manuscripts were
still made from parchment - the skin of a sheep or goat that's been
prepared for writing - or vellum, the skin of a calf. It took the
skins of 300 sheep to print one copy of Gutenberg's Bible.
However, by the sixteenth century, paper mills using old cloth
rags were springing up all over Europe. Linen was the predominant
source of material for paper, although cotton began to show up in
paper by the 18th century, as Europeans began to recycle cotton
rags.
Recycled rags were virtually the only source of papermaking fiber
in the Western world for over 700 years, until wood pulp processes
were developed in the mid-nineteen century. The first paper mill
in North America was built by the Spanish in Mexico City in 1575.
The first paper mill in what became the United States, built by
Dutch papermaker William Rittenhouse, was constructed in 1690 near
Philadelphia and used rags to produce paper, launching the American
recycled paper industry. The first patent for deinking wastepaper
was issued in 1800.
The rag shortages that led to an intensive search for alternative
sources of papermaking fiber resulted in four processes that could
be used to make wood pulp into paper. Wood was finally chosen as
the raw material of choice because of the vast forests that covered
the United States at the time, even though wood pulp is not a perfect
fiber source. Only about 50% of wood is cellulose that can be made
into paper, much less than the cellulose content of cotton or linen.
The first groundwood pulp mill in the United States was established
in 1867 in Massachusetts and the first commercial production of
wood pulp by chemical, or "cooking," processes was begun in 1887
in Ontario, Canada.
TREES VS. FORESTS
Nearly half of the trees cut in North America go to papermaking.
Paper companies cite lower percentages, claiming that most of the
trees are cut for lumber to make buildings, furniture and other
non-paper products. However, the lumber and paper industries work
closely together. A significant part of the tree cannot be used
for lumber and is chipped, instead, for papermaking. While some
of this collaboration between the lumber and paper industries represents
a good way to use what otherwise would be "waste" from resource
extraction (branches, stumps, "forest residue," sawdust), trees
are also being cut for papermaking when they're too small for lumber.
The paper industry now calls trees a "renewable resource," giving
people the impression that there is no problem with cutting trees.
It is true that trees can be replanted, in contrast to oil, ores
and minerals. But it is not that simple. Counting trees individually
misses much of their value. While some trees are grown on plantations
for the paper industry, particularly in the southern United States,
these replanted trees do not make a true forest. They are usually
managed intensively, with heavy use of petrochemical inputs such
as pesticides, herbicides and fertilizers. They are monocultures,
without the mix of types of trees, different ages, bushes, undergrowth,
snags, etc. that true forests have. Therefore they also do not have
the wildlife, birds, amphibians and biological diversity of a true
forest.
Unlike a true forest, replanted trees are not self-sustaining.
Buyers should be aware that tree pulp can only be reliably considered
"renewable" when the wood has been independently certified as sustainably-harvested.
The Forest Stewardship Council (FSC) uses the most environmentally
comprehensive third-party standards to certify forestry companies
and manufacturers that provide products from sustainably harvested
forests.
People often justify their commitment to reducing paper use and
using recycled or tree-free paper by saying that it will "save trees."
But it's really "saving forests" that should be the resource focus.
Trees are not a "crop" in the normal sense of the word. They are
not planted on agricultural farmland. Before a tree farm is planted,
forests have to fall.
Similarly, the paper industry claims that they plant more trees
than they cut. However, "plant" is the operative word. A large percentage
of the trees planted do not survive to maturity, nor are they intended
to, as the trees are thinned with growth.
The federal government owns more than 20 percent of all commercial
timber acres in the United States. On these lands, taxpayers heavily
subsidize the virgin paper industry through such forest services
as:
- building roads at below-cost in national forests,
- selling timber at well below market value,
- heavily subsidizing energy costs (EPA reports that recycling
paper saves 22-64% of energy costs over virgin paper production),
- subsidizing water costs (recycling uses 42% less water),
- giving special tax subsidies and write-offs to the timber industry,
- banning exports of most logs from federal land in the West,
which depresses the price of timber in the remaining domestic
markets.
The result is that forests that are supposedly held on behalf of
the public are instead given away at well below cost. Then the public
is required to pay high prices for the products made from them in
order to enrich the companies that the public has already subsidized.
This might have made sense in the 1890s, when such policies were
intended to settle the West and develop industries, jobs and transportation.
They do not make sense now, when they put more environmentally sound
production processes at a distinct disadvantage.
Once trees are diverted to papermaking, they are chipped into small
pieces and converted into paper fiber at a pulping mill. Even here,
there could be improvements. A 1991 Worldwatch State of the World
report on forestry determined that improved milling efficiency and
better technology could save 25% of trees. Another 25% could be
saved by improving packaging.
For fine paper quality pulp (e.g., that used for making printing
and writing papers), North American mills (and 77% of global pulp
production) most often use a chemical "kraft" process that cooks
the chips down into usable fibers. Wood consists of about 50% cellulose,
30% lignin (a tough, resinous adhesive that provides structural
support to the tree), and 20% easily extractable substances such
as aromatic oils and carbohydrates. Since high quality paper is
produced from cellulose, other substances, particularly the lignin,
need to be removed. Paper with a high lignin content will yellow
and age quickly when exposed to light.
Some fine papers are made in a mechanical "groundwood" process,
although this type of mill more often makes newsprint. Very literally,
the wood is ground up in this kind of pulping and the lignin is
left in the paper. Mechanical pulping is less expensive and more
efficient, using up to 95% of the wood versus 50% for the kraft
chemical process, but it produces a weaker paper with a high lignin
content. Some copy, computer and other office papers that do not
require long life are made with groundwood pulp. Groundwood is also
used to make many coated publication grades, although there are
also many coated sheets that are groundwood-free.
Many pulping mills are attached to a papermaking facility and the
pulp is dedicated to making that mill's paper. But other pulping
mills make "market pulp," to sell on the open global market, and
even mills that supply a particular papermaking facility often have
excess pulp to sell. Many mills integrated with a wood-pulping facility
have "closed" systems; the pipes carrying fiber from the pulping
mill to the start of the papermaking process cannot economically
accommodate market pulps, such as recycled.
Bleaching
As the pulp is made, it is also bleached. Chlorine was the bleach
of choice in the past, both because it gets the pulp (which otherwise
is tree-colored) the whitest and because it is the most effective
chemical at removing the five percent or so of lignin that remains
after cooking down the chips in the kraft process.
However, when chlorine is combined with carbon-based substances
such as wood, it produces by-products called chlorinated organic
compounds, including dioxins and furans. When released into water,
dioxins do not break down. As early as 1985, EPA labeled dioxin
"the most potent carcinogen ever tested in laboratory animals."
When fish eat contaminated materials, the dioxin travels up the
food chain, bioaccumulating in the fatty tissues of fish, sea birds
and mammals. Therefore, even a minuscule amount in water can create
a significant risk in humans and wildlife. Increasingly, research
links dioxins to endocrine, reproductive, nervous and immune system
damage.
The paper industry has instituted pollution prevention changes
that have reduced dioxin emissions by 92% since 1988. In the past
few years, virtually all mills in the U.S. and Canada have stopped
using elemental chlorine gas for bleaching. Almost all have switched
to using a chlorine derivative instead, primarily chlorine dioxide.
Now the industry says that most mills are at "non-detectable" dioxin
levels in their effluent. But "non-detectable" only indicates the
technological capacity of current testing methods at relatively
elevated government-required detection levels. It is not the same
as "zero concentration" of dioxins. In fact, dioxins can be - and
often are - measured at much smaller concentrations. In addition,
the "non-detect" tests measure only dioxins and do not account for
other potentially dangerous chlorinated organic compounds produced
in enormous quantities. Dioxin is only the tip of the iceberg. Almost
1,000 organochlorines are produced in the chlorine bleaching process
used by the pulp and paper industry. The health and environmental
consequences of many of these chemicals have never been studied.
While chlorine dioxide can significantly reduce the emission of
organochlorines (often cutting emissions in half), it does not completely
eliminate the production of these toxins. Although the paper industry
has had patents for chlorine-free bleaching technologies since the
early 1970's (one of these patents described chlorine bleaching
as causing "a serious pollution problem" in 1970), it has been slow
to implement chlorine-free processes. Europe has embraced TCF technology
much more quickly than the U.S.
EPA developed an integrated regulation, called the "cluster
rules," that reduces toxic and hazardous pollutant releases
by setting guidelines and standards affecting both water discharges
and air emissions. The goal of these "cluster rules" is to prevent
pollution in the first place, rather than devising more and more
complex technological "fixes" after the fact.
The cluster rules for wastewater standards recommend two options
for "best available technology economically achievable (BAT)" for
limiting effluent pollution. Both of these involve 100% substitution
of chlorine dioxide for elemental chlorine, with one of the options
adding oxygen delignification or extended cooking (both part of
the pulping process designed to further break down lignins). It
also includes a program to reward mills using technologies that
exceed BAT, namely totally chlorine-free processes.
Chlorine and its derivatives are highly corrosive to a paper mill's
pipes and so make it very difficult to close the effluent loop within
the mill and avoid discharging wastewater altogether. TCF, however,
by eliminating the corrosive factor, makes closed-loop systems much
more achievable, providing a significant environmental advantage
in preventing dioxins and organochlorines in the first place, and
allowing the wastewater to be recycled and cleaned within the mill
as well. Barry Commoner's Center for the Biology of Natural Systems,
at Queens College, New York, studied pulp and paper mills on the
Great Lakes. It found that converting these mills to TCF would raise
the price of pulp by only a few percent and that the use of chlorine-free
bleaching agents, although twice the cost of chlorine-based equivalents,
would allow the mills to use lower, and therefore less expensive,
grades of wastepaper.
CROPS
If paper is not made from trees, what else can it be made from?
As the Brief History of Paper above makes clear, paper has been
made from materials other than trees for most of its existence.
This is still true in many other parts of the world, where trees
are not as abundant as they are in North America. But even here,
we have plenty of non-tree resources for making paper, if we develop
the infrastructure necessary to support it. Not only could tree-free
furnishes reduce the demand on forests, they could also solve some
of our agricultural problems in an environmentally sound way.
Tree-free fibers range from very short to very long and each has
its own variation of processing requirements. But, technically,
any grade of paper can be produced by using an appropriate mixture
and processing of tree-free fibers and result in a quality sheet
of paper. Some crops, such as kenaf, even combine both long and
short fibers within different parts of the same plant, rather than
requiring the combination of different species, as with trees, for
optimizing performance qualities.
A number of papers made from agricultural crops have been introduced
into the marketplace in the past few years and proven themselves
to be functionally equivalent to wood-based papers. Some of them
are high-quality 100% tree-free papers; others are mixed with recycled
pulp and/or wood-pulp in a traditional papermill to make printing
and writing papers, as well as newsprint.
Cotton
Rittenhouse's Philadelphia paper mill, the first paper manufacturing
facility in the U.S., made recycled paper from cotton rags. Peddlers
traveled the New England states regularly, buying old cotton rags
from people's homes to make into paper. Cotton paper mills still
flourish in the U.S., making high-end fine papers. Most of their
pulp comes from cotton linters, short clippings that are a residue
left from secondary ginning by seed oil companies after the longer
fibers are removed from cotton bolls for fabric. The creative use
of this residue certainly qualifies as an environmental virtue.
At the same time, the tremendous amount of pesticides and water
(quite often in arid locations) necessary to grow the cotton for
clothing manufacturers, its primary market, creates other environmental
problems.
However, some cotton papers are made through processes that attempt
to reduce the environmental demand. One incorporates the clippings
left over from making clothing from cotton that is grown organically,
significantly reducing the environmental burden. Carefully grown
from heirloom seeds that reproduce cotton's original natural colors
of tan, green and cream colors, this pulp is not bleached at all,
lending these soft earth colors to the paper.
Other cotton papers incorporate materials such as postconsumer
paper (to qualify as "recycled" under most recycled paper definitions),
blue jeans, and even old money that has been taken out of circulation.
Kenaf
Beginning in the 1950s, the U.S. Department of Agriculture evaluated
hundreds of fiber crops and determined that kenaf was the best option
for tree-free papermaking in the U.S. The fact that kenaf fibers
have many similarities to wood fibers increased its potential adaptability
to the current system. But despite the government's endorsement,
kenaf production has developed very slowly. Related to hibiscus,
kenaf is a fast-growing plant that can be harvested annually over
several months, then compressed and stored for up to four years.
Farmers in the South are already growing it, without the need for
expensive and damaging pesticides. It yields far more fiber per
acre than a comparable-size tree plantation.
The amount of U.S. agriculture currently dedicated to kenaf is
still minuscule, although it is a popular papermaking furnish in
other parts of the world. But it has great possibility as an environmentally
sustainable crop that can bring new life to rural economies shattered
by the demise of their original industries. In fact, the more than
40 jobs that growing kenaf has brought to Tallahatchie County, Mississippi
have been part of revitalizing one of the most economically depressed
areas in the U.S.
Currently, domestic kenaf paper is produced on rented time in paper
mills dedicated to other furnishes. Pulping kenaf requires less
energy than pulping wood and it is more easily bleached with totally
chlorine-free processes.
Hemp
Hemp is a versatile, invaluable plant used all over the world for
many life-sustaining needs such as oil for food and fuel, edible
seeds, and fiber for textiles, rope and paper. In fact, the first
paper back in second-century China was made from hemp. But, in an
attempt to suppress the cultivation of hallucinogenic marijuana,
hemp was outlawed in the U.S. in the 1930s. Despite government assurance
that the law would not curtail fiber and seed production from industrial
hemp (a distinctly different, non-hallucinatory plant) and a government
program promoting the farm production of industrial hemp as a patriotic
duty during World War II (because imports for textiles and ropes
had been cut off by the war), federal drug agents harassed fiber
producers so relentlessly that its production died out in the 1950s.
A few hemp papers are currently imported into the U.S. from European
and Asian sources. Some determined entrepreneurs have arranged for
hemp-pulp shipments from other countries in order to make high quality
paper here. But there is a growing movement to rescind outdated
prohibitions against growing such a productive and useful plant.
Efforts are particularly strong in Kentucky, which provided much
of the seed for hemp when it was still legal. Now that Kentucky's
current predominant crop, tobacco, is falling out of favor, farmers
in that state are looking back to their past for the possibility
of a promising future.
Both Hawaii and Vermont passed initiatives in 1996 to permit studies
of the feasibility of growing industrial hemp. The American Farm
Bureau Federation voted overwhelmingly in favor of "research into
the viability and economic potential of industrial hemp production
in the U.S.," including planting test plots. Canada is quickly lowering
barriers to growing it at test sites.
Other Crops
Some papers, mostly imported, are available made from other crops,
as well. These include sugar beet and corn by-products as well as
algae and bagasse (sugar cane). There are also papers made from
tropical grasses, including bamboo. There is concern about whether
the Asian bamboo can be guaranteed to be grown sustainably, rather
than encouraging damage to more indigenous forests.
AGRICULTURAL FIBER RESIDUES
More than 200 million tons of cereal straw are dumped or burned
in open fields each year. None of that is necessary because all
of the straw could be pulped and used for paper, if the proper technology
and infrastructure were in place. In fact, agricultural residue
could replace a significant amount of trees for newsprint and printing
and writing paper and solve a vexing agricultural and air-quality
problem at the same time.
One of the advantages of pulping wood, welcomed even in the 1800s,
is that trees provide their own "storage unit." They do not require
a seasonal harvest time and form a compact "bundle of fibers" for
transportation and production. These advantages encourage centralized
production facilities. Pulping agricultural residues reverses that
system. Although the cyclical harvest times of straw and other crops
hampered paper production 150 years ago, modern harvest methods
can compact bales and wrap them in protective covers that allow
year-round storage. But their greater bulk encourages more local
and labor-intensive facilities, thereby aiding local rural economies.
Pulping from agricultural residues also does not require new land
to be put into production and the lighter fiber colors are more
easily bleached with totally chlorine-free processes.
Small quantities of paper made from agricultural residues (some
of it combined with postconsumer recovered paper to produce a recycled
blend as well) are already available on the market. But with sufficient
investment, the potential for these papers is immense. Two private
companies funded a successful test of newsprint partially made from
agricultural residues, with the support of major West Coast newspapers,
including the Los Angeles Times, the Sacramento Bee, and the western
edition of the New York Times.
RECYCLED PAPER
No matter what the furnish, paper will continue to need to be recycled.
Once recovered paper reaches the mill, it must be pulped to prepare
the fiber for recycling. In some cases, recovered paper can be dumped
directly into a beater, a huge tank that separates the paper fibers
by simply washing them like a giant mixer. But most recycling mills
use some form of deinking in order to remove the inks, laser and
copier toner, and contaminants such as labels, glues, plastic windows,
paper clips and other materials. Modern deinking combines processes
that wash, separate, sieve, tumble and rotate the fibers. When completed,
the clean, usable fiber is piped to the pulper or the papermaking
machine, while the excess materials are skimmed off or dropped through
centrifugal force into a "sludge" that is then burned for fuel,
otherwise used or landfilled.
Some recycling mills have integrated their deinking system with
a paper machine, which means the recycled pulp is piped directly
to the machine. But most are non-integrated: they have open pulpers
which can accept fibers and pulp from many sources. They often buy
the virgin portion of their paper furnish on the open market, as
semi-dry bales of rough fiber sheets, and dump it into the pulper
with the recycled fiber.
U.S. printing and writing paper, taken as a whole, currently averages
just over 10% recovered content (many papers have none, some have
100%). But this American Forest & Paper Association (AF&PA) statistic
includes preconsumer tonnage, the scraps left over from production,
converting and printing processes before the paper ever reaches
consumers. The amount of postconsumer fiber (recovered from offices
and homes), by far the greatest amount of fine paper being disposed
of, in printing and writing paper is much lower. Clearly, the amount
of recycled content in printing and writing papers can and should
be far higher.
Is Deinking A Problem?
Deinking removes inks, dyes and other contaminants from recovered
paper, as well as fibers too small to be incorporated into new paper.
For printing and writing paper, between 20 and 30% of the original
scrap paper ends up as paper sludge after deinking.
Although deinking is not a totally benign process, most of its
environmental problems stem from what is added to the paper when
it is made the first time around or from how it is used before it's
collected for recycling. In order to solve environmental problems
caused by paper disposal, we need to eliminate the toxic materials
used in inks and dyes, and discontinue the use of chlorine for paper
bleaching.
Deinking is primarily a mechanical process. The only potential
area of environmental concern stems from the chemicals added to
clean the scrap paper. In the past, recycling mills have used toxic
solvents and detergents, but state-of-the-art deinking systems no
longer require these. The caustics, detergents and surfactants used
in deinking are not considered to be toxic chemicals by the EPA.
Although some end up in the sludge, the rest end up in wastewater,
where they are neutralized with hydrochloric and sulfuric acids.
The resultant chemical reaction produces harmless salts such as
sodium chloride or sodium sulfate.
The major source of paper sludge contamination comes from the dyes
added to the paper by manufacturers and inks added by printers,
as well as organochlorine contaminants added in the bleaching process
by paper producers.
Heavy metal contamination from inks is one of the most serious
problems in disposing of paper sludge. Over the years, the printing
industry has worked to reduce some toxic elements of printing inks.
For example, lead from printing inks, which accounted for 12% of
all the lead in the municipal waste stream in 1970, now makes up
less than 1%. Other environmentally toxic metal pigments such as
arsenic, cadmium, zinc, manganese, mercury, potassium, copper, chromium
and nickel show up in sludge because they are still used to make
some printing inks.
Another of the toxics that continues to show up in paper sludge
is polychlorinated biphenyls (PCBs). These come almost exclusively
from the 44 million pounds of PCBs used by carbonless paper manufacturers
between 1957 and 1971. Although not used after 1971, they are still
showing up in wastepaper from offices cleaning out old files. A
smaller potential source of PCB contamination in papers is the 50,000
pounds used in printing inks between 1968 and 1971.
The other major hazard in paper sludge is organochlorine contamination
from the original paper bleaching process. This problem is compounded
if the deinking mill itself uses chlorine or a derivative in the
bleaching of recycled paper. Some recycled paper mills are leaders
in avoiding the use of chlorine and chlorine derivatives.
Most deinking sludge currently ends up in privately owned landfill
sites, although some mills are allowed to use municipal landfills.
The sludge is about 40% solids. A few mills burn deinking sludge,
which eliminates 75% of its volume. However, the 25% that is left
contains virtually all the toxic materials contained in the original
sludge (including all the heavy metals), and requires special handling.
In addition, incineration results in toxic air emissions which must
then be controlled. Several mills use the sludge as fertilizer.
The major danger with this disposal method is organochlorine and
heavy metal contamination. Other alternative methods for sludge
disposal include using it as a carrier for agricultural pesticides
and herbicides by drying and pelletizing it. This is obviously a
potential environmental hazard, since it involves adding potentially
toxic pesticides and herbicides to an already contaminated carrier.
Despite these potential problems from sludge, deinking is a more
benign and environmentally sound process for handling used paper
than either landfilling or incineration. Since virtually all of
the sludge problems stem from contaminants in the paper before it
comes back for recycling, those same contaminants exist in paper
that is landfilled or burned. However, the toxics and pollution
from inks, dyes and chlorine cannot be controlled in a landfill,
where the paper is spread throughout the area. In incinerators,
they become concentrated in either toxic air emissions or hazardous
ash, which then must be landfilled. When, instead, the paper is
recycled, the potential problems are reduced to a comparatively
small, solid mass which then can be handled with more stability.
There are also some recycled papers on the market that are produced
from postconsumer, non-deinked paper. While certainly the most environmentally-sound
paper available, it will never take over more than a small share
of the market, since manufacturers can only use the "cream of the
crop" clean postconsumer waste in order to make this paper.
The Environmental Benefits of Recycling
In the early 1970s, an EPA study for Congress concluded that using
one ton of 100% recycled paper saves 4,100 kwh of energy (enough
to power the average home for six months) and 7,000 gallons of water.
It also keeps more than 60 pounds of pollution out of the air. Paper
mills have become much more efficient since that time, but recycling
paper still results in far less resource and environmental demand
than making virgin paper.
That one ton of recycled paper also saves 3.3 cubic yards of landfill
space, which is increasingly important as many local landfills near
their capacity. Because size, height and usable parts of trees vary,
it is hard to estimate exactly how many trees go into making a ton
of recycled paper, but paper industry representatives have estimated
that one ton of recycled paper saves approximately 17 trees.
In 1995, the Environmental Defense Fund (EDF), through its Paper
Task Force, compared the energy requirements and environmental releases
from 100% recycled fiber-based and 100% virgin fiber-based systems.
EDF used a comprehensive approach which considered many life-cycle
aspects to better assess the full range of environmental consequences.
For recycling operations, this included collecting, transporting
and processing recovered paper, as well as disposal of residuals
from recovery facilities and paper manufacturing (sludge). For virgin
paper operations, it included harvesting trees, transporting logs,
debarking and chipping, as well as collection of the paper after
its use and transport and processing at landfills and waste-to-energy
incinerators. For both systems, it included appropriate pulping
and manufacturing processes. EDF's analysis showed "clear and substantial
environmental advantages from recycling all the grades of paper"
they examined, including printing and writing paper, and listed
more than a dozen parameters.
Recycled paper also needs less bleaching than virgin paper. Because
the paper was bleached in its first production cycle, it can use
less bleach and more easily avoid chlorine bleaches the second time
around. Several recycling mills are processing their paper chlorine-free
(PCF), although the paper probably still carries some chlorine from
its original production. However, few of these mills then combine
the PCF fiber with TCF virgin pulp. Since many buy their virgin
pulp on the open market, it is reasonable to assume that much of
it is still chlorine-bleached.
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