LISTENING
STUDY Question 52:
Can tree free papers be recycled?
Yes,
agricultural fibers can be recycled. As fibers are recycled
the fibers get shorter. One of the advantages in agricultural
fibers is that they have various lengths. Jute and Kenaf
have lengths as long as 7 mm. The quality of paper can
be tailored accordingly by using long or short fibers.
- James S. Han, Research Chemist, USDA Forest Service
Forest Products Laboratory
Yes,
agricultural fibers can generally be recycled, but any
recycled fiber is subject to degradation after consecutive
cycles. The ultimate viability of recycled agricultural
fibers will be determined by the products made from
these fibers, and the demand for these papers in the
market. - International Paper
Any
cellulose fiber can be recycled. The shorter the fiber
gets, the less value it has in the process. -
Jeff Lindenthal, President, Green Field Paper Company
Yes.
- Jeanne Trombly, Fiber Futures
Yes.
The degree to which they can be recycled depends on
the fiber. 100 percent flax or hemp or other long bast
fibers can probably be recycled three times as much
as wood. Cereal straw residues are short fibers and
cannot be recycled as many times. - Living
Tree Paper Company
Yes,
but even most poor papermaking fibers can make it through
the recycling process when the makeup of tree-free fibers
is a small percentage of the furnish. If one intends
to expand the use of tree-free fibers out of a specialty
market, the fiber must efficiently mix with tree-fibers.
Fibers that are too long or too short can interfere
with draining and may have a short lifespan. A strong
papermaking fiber such as kenaf can be recycled at least
as well as tree fibers. - Tom Rymsza, President,
Vision Paper
Of course, it can be recycled.
See, for example,
my presentation, "Experience in the Technical and Market
Development of Agri-Pulp Printing Papers in North America."
- Al Wong, Founder, Arbokem
Yes, there are no barriers. Ag-fiber papers have
longer, stronger, and tougher fibers than most tree
fibers, so they generally enhance the recycled fiber
supply. - Peter Hopkins, Environmental Papers
Consultant for Crane Paper Company, Gargan Communications
Tree-free
papers should be able to be recycled several times.
Given the current technology, the nonwood fibers would
not actually be longer in a real-world setting. Therefore,
they don't give any advantage when mixed into the recycled
paper slurry.
When processed for
specific purposes, the nonwoods can have much longer
fibers, which is why they are stronger than comparable
wood fibers. Technically, they do well for being thin
because of the longer fibers, hence they are used in
cigarette filters, tea bags, etc. To say that nonwood
fibers add strength to recycled papers is unproven and
would require scientific study. - Jeff Mendelson,
President, New Leaf Paper
Most nonwood fibers are thinner than wood fibers
and more fragile to mechanical treatment. Deinking during
recycling involves fairly strong mechanical action.
Therefore there is some worry and some evidence that
nonwood fibers would break down more than wood fibers
during the recycling process.
Yes, they can be
recycled but the recovered yield will be lower than
for wood fibers. - Michael Jackson, Consultant,
Tolovana Park, OR
Yes, agricultural fibers can be recycled. In fact
a good market opportunity for long, agricultural fibers
is to help extend the amount of times pulp can be recycled,
by offering strength.
There should be
no problem in recycling nonwoods. All papers have a
given life-span, or number of times they can be recycled.
The nonwood paper life span should be on par with virgin
pulp papers. - Peter A. Nelson, President,
AgroTech Communications, Inc.
One of the optimal mixes is a blended recycled
paper and Arundo donax. - Ernett Altherimer,
Founder and Chairman, Nile Fiber
Preliminary
studies have examined the effects of pulping and recycling
on kenaf. It has been shown that most nonwoods have
a lower lignin content than wood and that it is easier
to delignify nonwoods, as they have a lower activation
energy. There have also been investigations into the
changes suffered by fibers during the recycling of wheat
straw pulps. The results of this work implied that wheat
straw pulp did not behave differently from wood pulp
during recycling. - Pande 1998
The biggest issues might be color - when recyclers
want post-consumer waste, they want white paper. They
might not want the nonwood papers if they are not as
bright. - Russell Clark, Environmentally Preferable
Purchasing Program. US EPA
We
would like to see more information on this topic. Post
consumer waste should be able to be used about 7x before
it is not usable. We would like to know the lifetime
of the nonwood papers. Also, we'd like to know if alternative
fibers can satisfy the requirements for virgin pulp
in the recycling industry. - Tyson Miller,
Program Director, Recycled Products Purchasing Cooperative
The
industry has very limited experience with this question.
Our evaluation found no difference on recyclability.
We would expect similar characteristics as with wood
fibers - recycling them results in shorter fiber length
(the repulping causes breakage and shortening).
- Richard Denison, Ph.D., Senior Scientist, Environmental
Defense
Recycling
of nonwoods fibers: In considering the impact of alternative
fibers on the global fiber supply, at some point the
potential for recycling nonwood fibers must be established.
Preliminary studies have examined the effects of pulping
and recycling of kenaf. It has been shown that most
nonwoods have a lower lignin content that wood and that
it is easier to delignify nonwoods, as they have a lower
activation energy (Pande and Roy, 1996). There have
also been investigations into the changes suffered by
fibers during the recycling of wheat straw pulps (Xumei
and Xiachun, 1996). The results of this work implied
that wheat straw pulp did not behave differently from
wood pulp during recycling. - Pande 1998, citing
Pande, H. & Roy, D.N. 1996 and Xumei, Z. & Xiachun,
Y. 1996.
Another question raised about the technical feasibility
of using non-wood fibers for papermaking is their recyclability.
In general, non-wood fibers are as recyclable as wood
fibers and the same issues exist. The strength of pulp
made from recovered fibers determines its usefulness.
Fiber length as well as fiber bonding ability determine
pulp strength. Recovered fibers on average, are shorter
than virgin fibers and lose strength with each reuse
cycle. For nonwood fibers that are generally shorter
than wood fibers (such as wheat straw), issues such
as slow drainage and low strength are a problem both
in virgin production and recovered fiber paper production.
On the other hand,
non-wood fibers with greater fiber length (such as kenaf
or hemp bast fibers) can be used to compensate for loss
in pulp strength from recycling. Depending on the strength
of the non-wood fiber, more or less virgin pulp has
to be added to the deinked pulp to produce high quality
recycled paper. - Environmental Defense Fund
Paper Task Force, White Paper 13, "Non-Wood Fiber Sources"
We
have very successfully recycled kenaf paper to prove
its compatibility with existing systems. We have taken
tons of kenaf waste paper to commercial scale mills
and blended it with wood based waste paper with excellent
results. We regularly blend kenaf pulp with recycled
pulps. - Tom Rymsza, President, Vision Paper
We
have heard concerns that agricultural residues might
create problems with recycling, but we do not know whether
these are true or not. The concerns have to do with
the short ag res fibers falling out of the system and
clogging the machinery. We assume that a clogging problem
could be corrected technologically. A problem with the
fibers being too short to recycle might be of more concern.
We believe that recycling is a fundamental foundation
for an environmentally sustainable paper production
system. If papers with ag residue fibers were "one-way
papers" because they could not be recycled, that would
land us back where recycling started. Even though the
ag residues would be recycled from a waste material
to begin with, most are combined with other types of
fibers to bring in the attributes that they lack. Large
fiber losses at the recycling mills could undermine
that system. So we believe it is important that this
question be answered and any problems resolved early
in the development of production systems for agricultural
residue papers. - Susan Kinsella, Conservatree
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