LISTENING
STUDY Question 47:
Are there differences in quality or performance for
tree free papers?
In
general the agricultural fibers are usually about the
same length as deciduous wood fibers, but shorter than
coniferous wood fibers. Kenaf grown in tropical area
will have fiber length of 7 mm or longer. Agricultural
fibers will produce a wide variety of papers such as
currency paper and calligraphy paper that require long
and thin fibers. - James S. Han, Research Chemist,
USDA Forest Service Forest Products Laboratory
Yes, there are significant differences.
- Living Tree Paper Company
Yes,
these differences are dictated by each fiber type. Hemp,
for example, has much different characteristics than
rice straw. - Jeff Lindenthal, President, Green
Field Paper Company
Yes. Quality and performance are factors of the
raw material and the manufacturing process. Good and
poor qualities of paper can be produced from either
wood or agriculturally based papers. - Tom
Rymsza, President, Vision Paper
Kenaf
and hemp core pulps and rice and wheat straw pulps appear
to have the lowest strength characteristics - below
that of hardwood pulps and far below that of softwood
pulps. - Environmental Defense Fund Paper Task
Force, White Paper 13, "Non-Wood Fiber Sources"
It
depends on the appropriate selection of agri-fibers,
pulp technology, and papermaking technology.
See for example,
my presentations, "Agri-Pulp Newsprint" and "Experience
in the Technical and Market Development of Agri-Pulp
Printing Papers in North America." - Al Wong, Founder,
Arbokem
Yes, there are wide variations in quality.
- Jeanne Trombly, Fiber Futures
There
are no quality or performance differences between kenaf
and wood. - Tom Rymsza, President, Vision Paper
Yes,
there are substantial differences in the quality and
performance of paper made from agricultural fibers versus
wood fibers. Differences are dependent on the type of
agricultural fiber used, the relative amount of each
fiber used, the grade of the paper being made, and the
application of the paper by the consumer. Consumers
have historically chosen wood based paper products because
of their high quality and relatively low cost.
- International Paper
The
market and performance will bring this out, but theoretically
any agricultural fiber can be made into wood type products.
Re-Vision paper
works better in appearance and machinery. But in real
markets, cotton based toilet papers are inherently better.
Trying to pound-for-pound replace newsprint with [tree
free] newsprint or copy paper isn't an advantageous
path. We should be making funky filters for Italian
cars and other specialty products. - Peter
A. Nelson, President, AgroTech Communications, Inc.
Experiences with a product are highly varied.
The quality and performance potential is probably dependent
on the experience of those trying to use the products.
Another consideration
is that nonwood paper producers often are not coming
from multi-generational experience. While a copy paper
mill had years to perfect the processes to produce precisely
what the consumer wants, new mills have to start from
scratch with an extended trial-and-error process. Therefore,
if the papers don't initially perform as well, it may
be due to lack of expertise rather than fundamental
flaws.
An overlying concept
with these papers is that before we get into the economics
and other challenges, we really need to prove that nonwood
papers provide a better environmental profile and outcome.
Having not shown that, investment is hard to come by.
We're hoping that the Listening Study will point to
the best opportunities. From there, there can be many
opportunities, whether they are public, private, or
partnership-based. Ideally we can lay out the science
in a sensible way to find small gaps and decide if it
makes sense to continue promoting tree-free papers.
At this point, no one in particular wants to assume
that trees are bad, nor should we make such assumptions.
It is not clear that agricultural fiber is necessarily
better than an equivalent acre of trees. It may not
be a "one or another" thing. Trees might be ideal for
certain products and places whereas agricultural fibers
might be better in other mixes. - Russell Clark,
Environmentally Preferable Purchasing Program, US EPA
Clearly
there are very significant differences between nonwood
fibers that might be used to make paper. But of the
nonwood papers that have actually been brought to market
in the U.S., including some using agricultural residues
and others using on-purpose crop fibers, we have heard
of no problems from paper purchasers. By the time they
get that far, the producers seem to have worked out
enough technical problems that the papers themselves
are high quality. - Susan Kinsella, Conservatree
Hemp received a favorable initial rating
in the USDA study. Hemp and Kenaf are not related, but
they do have similar characteristics. Unfortunately,
it is illegal to grow hemp in the US, and the yields
per acre indicate a high cost of raw material which
is not competitive with wood fiber. Additionally the
strong bast fibers are dramatically different than wood
fibers, and they require additional processing to prepare
a pulp suitable for commercial type papers.
Agricultural
residue is a broad term, but in the context of pulp
and paper, it usually means corn stalks and various
hays, primarily wheat straw and rice straw (but could
include other straws from grains). Since pulp and paper
making requires homogenous material to produce consistent
results the mixing of different types of agricultural
residue is not indicated.
Additionally corn
stalks and straws contain a high level of silica, which
has significantly negative implications for chemical
recovery and environmental compliance at a pulp mill.
While novel processes have been proposed to alleviate
the silica problem, none are commercially proven or
in current operation.
Corn stalks are
the most abundant agricultural residue material available,
and there has been some historic use as a raw material
in pulping, albeit, limited. Corn stalks produce a low
pulp yield. For every one ton of pulp, you get two tons
of waste material which contains a high amount of silica.
The short weak fibers will probably be detrimental to
recycling.
Straws are
another abundantly available raw material, and they
have a more extensive history of use in the industry,
with the last straw pulp mill in the US ceasing operations
in 1960. Wheat or Rice Straws contain short, weak fibers,
a high level of silica and, like corn, will not recycle
well.
Flax and
cotton are mature on-purpose crops that have
historic use in pulp and paper, especially specialty
grades. They both yield long fibers, (much longer than
wood fibers) and both carry a very high raw material
cost when compared to wood.
Both bamboo and
arundo donax were considered in the USDA study,
and both plants have received recent attention in the
nonwoods sector. Both plants are perennials (grasses-
multi-years to harvest) and not conducive to farming
that is based upon annual row crops. They both have
a physical structure that is suitable for chipping,
which produces a wood-like raw material for the pulp
mill in-feed. Both plants produce high yields per acre,
and a pulp similar to hardwood pulps.
Bamboo pulp
is produced in Asia, and it should be noted that bamboo
forests provide the sole food source for the Panda Bear,
which is an endangered species.
Arundo Donax
grows in the wild in California and can be propagated
elsewhere. It is sometimes call "giant reed" and it
is used to made reeds for wood-wind instruments. It
is considered a highly invasive toxic pest in California,
where efforts exist to eradicate it.
Bagasse (sugar
cane) fiber is a by-product of sugar production. It
is a hardwood-like fiber that has historically and currently
been used for common paper products in areas where a
sugar cane industry exists. After the sugar is extracted,
burning the leftover bagasse fibers for energy value
or pulping for paper are two uses for this process residue,
and both uses are common. Bagasse has a lower silica
content than corn stalks or straws. - Tom Rymsza,
President, Vision Paper
Kenaf is one of the best alternatives because
it is a "New Crop" and that is really good for sustainable
agriculture. The Search for New Fiber Crops program
selected it as the most viable plant to replace trees
in paper making. That search program also identified
crotalaria and roselle as high potential.
Kenaf was chosen
because its outer bast fiber was similar to softwoods,
and its inner core is similar to hardwoods. The whole
kenaf stalk can be used to make high quality paper.
Kenaf has a low lignin content, so the chemistry needed
to convert it to pulp is less than that used for trees.
Kenaf produces a pulping yield of 50% or more, using
less energy, making it an efficient raw material. It
does not contain silica, so it is suitable for existing
well known and well proven chemical systems, and can
be processed without producing additional environmental
liability. Kenaf's raw material cost is competitive
to wood fiber, and it is a very environmentally sound
crop, requiring lower chemical use than most other crops.
It is a fast growing
plant, growing from seed, planted in the spring, to
a height of 12-18 feet tall in about 5 months. In studies
in cooperation with the University of Tennessee using
no-till agriculture, we have demonstrated that it can
be economically grown using lower chemical inputs than
other crops in that region, particularly cotton.
It produces about
six tons of fiber in this time period, and that is two
or three times the fiber produced by trees in a forest
in a twelve month period. That high level of fiber production
means it is absorbing CO2 and sequestering the carbon
faster than a forest. - Tom Rymsza, President,
Vision Paper
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