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Hemp in biocomposites
Erwin Lloyd
BioComposites Solutions, P. O. Box 2928, Blaine, WA 98231-2928
Economically attractive opportunities exist
for incorporating bast fiber plants, including hemp, into composites. Careful
consideration of product development, however, is important in order to improve the
potential for success. In order to maximize the potential of a hemp-based composite,
it is important to consider the production costs relative to a similar product made from
competitive materials such as wood. This assessment is particularly important in
regions that experience rather low-costs for competing fibrous materials. Even the
least expensive portion of hemp, the core section, is generally more expensive than such
wood residue as sawdust or shavings, which may be used to form particleboard and,
increasingly, medium density fiberboard (MDF).
Hemp as an annual crop has special challenges
relative to a year-round harvestable product such as wood. These become
obvious concerning the Fall harvest, raw material transportation logistics, additional
storage costs, and biological degradation during storage. These factors further
detract from the commercial viability of agriculture-based composite materials.
These disadvantageous factors are magnified when hemp materials are competing against
low-cost wood residue produced in large-scale operations. In light of these factors,
commercially viable products need to be competitive in terms of both performance and cost.
On the other hand, wood costs are generally
rising with demand surpassing supply. In fact, the international wood-based fiber
supply balance is now beginning to shift in favor of alternative fiber materials,
including industrial hemp. In light of these changes, hemp fiber may become
increasingly competitive in price relative to wood, particularly since only aspen and
poplar, fast-growing tree species, are alternatives to conventional wood sources in
northern latitudes such as the northern United States and Canada.
Many rural communities, particularly those
which are struggling, are keenly interested in opportunities to augment their
manufacturing base and their overall economy. This strong desire to find solutions
provides the impetus to assist in providing necessary support to bring such a project
together. When considering the best products to be made from hemp, one must
determine the distinctive properties of the particular agricultural material in question
and pay particular attention to hemps advantages in terms of economics or
performance, relative to established similar applications with conventional materials.
The following recommendations apply.
Develop a product that accentuates its
advantageous features, while minimizing its negative aspects: for example, the higher
yields and greater strength of hemp fibers. Look for products which can better use
hemp in its natural form. Greater effort, energy, and cost is needed to break hemp
stalks into small pieces for particleboard, as compared with the already small size of
wood sawdust or shavings. Consequently, a better choice for hemp may be select a
product that would use longer lengths of the stalk.
Review the history of similar products or raw
materials such as flax, kenaf or other bast materials. Many good ideas in the past
have died due to a change in personnel or a cut of research and development budgets.
Todays market may have enhanced the economic viability of an idea or product
from the past. Explore recent technological developments. New technologies may
reduce processing costs and can certainly bring enhanced features and performance to
composites. This can make a hemp-based composite an economically viable and even
lucrative venture. In recent years, more groups have begun to focus on these areas.
Adapt various processing and product
development ideas from other industries. Most new inventions, especially processes,
are simply new combinations of existing ideas.
Consider the level of production anticipated,
relative to that of the closest competition. In recent years, non-wood bio-based
composites output has generally been 10-50% that of a comparable wood-based facility.
This disparity generally grants much greater economies of scale to any similar
wood-based product. The lower level of production of agriculture-based composite
materials is due somewhat to the unproved nature of these non-wood material ventures, but
primarily it is due to a lack of funding.
If competing on a commodity basis, try to
maximize capacity. Generally, added productivity far outweighs additional line costs
for processing machinery. For example, in a recent feasibility study, 14% additional
total project capital costs devoted to larger machinery in a single line yielded an
increase in productivity of 40%. If limited funding restricts a group to consider
only a smaller-scale production plant, then it generally is best to try to target a
specialty or niche market for the product.
In order for hemp products to be economically
viable under todays conditions, it is preferable for them to be distinguishable from
wood-based products made from low-cost raw materials. This is especially true for
particleboard and to a lesser extent MDF. If applications for products such as
particleboard or MDF are considered, it is preferable for them to have specialty uses
commanding a higher price. Static-free particleboard for use in electronic clean
rooms commands a price 2.5 times greater than that of conventional particleboard, through
the addition of a special charged substance. Moreover, lower levels of production,
common in non-wood composite operations, may well be more compatible to this
applications volume-limited niche or specialty market.
Evaluate adhesive costs, especially those
relative to those costs for competing applications. In traditional large-scale wood
composite plants, such as MDF plants, the total raw material adhesive costs are generally
equal to their fiber costs. These adhesive costs may be US$ 7 million per year or
more. Such costs with non-wood materials, including hemp, are often 1.5 - 3 times
more expensive for a given volume, than that of wood-based composites. Consequently,
this is a crucial consideration in terms of overall financial viability.
In business plans and financial modeling, be
certain to calculate profitability over the full breadth of historic product prices
both highs, and especially, lows. This analysis is particularly relevant for
commodity products such as particleboard, MDF, and oriented-strand board (OSB). Many
raw material, adhesive, and processing choices will be profitable and viable in time of
high or even average product prices. The real test is whether a plant, with its
rather expensive equipment and high capital investment, can be profitable, or at least
break even, during the historic lows of product pricing which invariably will occur.
Consider hemps compatibility with other,
preferably nearby, materials in composite products. For example, bast fibers such as
flax, hemp, or kenaf can provide fiber reinforcement as a substitute for glass fibers as
structural reinforcing agents in other materials, such a concrete, wood, and straw.
Straw in a lower density form could provide internal insulating features, while higher
density straw or bast fibers may supply strength in exterior portions of the product.
For further information contact Erwin Lloyd at: Tel: (604) 738-4180, Fax: (604) 738-4180, E-mail: biocomp@intergate.bc.ca, Home page: http://www.forestnet.com/cascade/index.html