Kenaf: Annual Fiber Crop Products Generate a Growing

synthesis gas (a mixture of carbon of the cheapest per unit weight as well monoxide and hydrogen), and syn- as one of the most abundant renewable thetie natural gas. These materials, in resources that we have. turn, provide raw materials identical to those used in the existing petrochemi- Summary cal industry. Plants contain a host of compounds In summary, lignocellulosic materi- that are chemically useful in making als are a resource that will always be industrial products. To develop indus- produced at the same time that we are trial products, we need to think of producing crops for food, feed, fiber, plants not just as commodities but as or chemicals. Wood wastes, harvest- "living factories" for chemical raw able field residues, and most food- materials. The major materials present processing wastes can be collected as in all plants are the three described sources of lignocellulosics. The here—oils, starches, and chemical functions of lignocellulosics lignocellulosics—and protein and permit their use either directly as naturally derived chemicals. Together, chemical derivatives or indirectly as a these materials are the source of a source of C-H-O compounds for fur- broad range of products from medi- ther chemical synthesis. As a category cines to newsprint, from jet engine of materials, lignocellulosics are one lubricants to lipstick. □ by Charles S. Taylor, Genera! Kenaf: Manager, Kenaf International, McAHen, TX, and Daniel E. Kugler, Director, Annual Fiber Office of Agriculturai Materials, CSRS, Crop Products USDA, Washington, DC Generate a Growing Response From Industry "Don't put shade on it." newer groups of interested farmers in That is the only general crop man- the Mississippi Delta, the plains of agement recommendation for the Oklahoma, the tidewaters of the Caro- steadily increasing number of kenaf linas, and the valleys of California— growers in areas of south Texas and are quickly learning that growing this southern Louisiana. They—along with annual hibiscus fiber crop is compara- 92 Part 111. Products From Nontraditionai Crops lively easy, requiring few inputs and began in the 1940's with fiber projects little management. in Cuba, Guatemala, Mexico, and El But, being easy to grow is an insuf- Salvador. Nevertheless, kenaf has ficient attribute. There must be a use been and still is a major fiber crop in and a market for the crop. The neces- Africa and parts of Asia, where the sary technologies must exist, and the long bast fibers from its bark are pro- crop must be economical to produce cessed for use in various cordage and use. Each of these attributes is im- products such as burlap, rope, and portant as a crop-to-product system twine. evolves. The principal purpose of kenaf pro- Kenaf, Hibiscus cannabinus L., is duction is to grow tall stalks that upon an annual fiber crop that is now, after maturity (in about 6 months) can be years of public and private research cut in various lengths and ground for and development efforts, in the early use in the manufacture of pulp and pa- stages of commercialization in the per products such as newsprint or United States. There are those who tissue. claim that kenaf fiber has been found in the ancient pyramids of Egypt. But Bast and Core it is still considered a "new" crop in Some uses of the fiber crop require the Americas, where its introduction separating the two distinct fibers in the Kenaf, Hibiscus cannabinus L, is an annual David Nance/USDA 88BW1573-23A fiber crop that is now in the early stages of commercialization in the United States. New Crops, New Uses, New Markets 93 Marvin Bagby, an ARS researcher, examines a stalk of kenaf. The long, outer bark and short, inner core fibers are processed into newsprint. USDA 88BW1884-4 ARS soil scientist L.N. Namkin examines a stand of kenaf at Rio Farms in Texas' Rio Grande Valley. Kenaf has the potential to supplement or replace wood-based paper pulp. David Nance/USDA 88BW1573-12A kenaf stalk—bast and core. The long, stringy bast fibers of the outer bark comprise 30-35 percent of the stalk by weight and are similar to jute in ap- pearance and traditional applications. The bast is used to make cordage products and specialty pulps, and may be used as a substitute for fiberglass in certain applications. The balsa-wood-like fibers of the stalk's interior, or core, have tradition- ally been either burned for fuel by Both pulpy center and fibrous exterior of peasant farmers in Asia or Africa or bamboolike kenaf are used to produce discarded. However, they can be used newsprint and other fiber products. for a variety of products such as poul- David Nance/USDA 88BW1576-9A try litter, packing materials, and mulch. 94 Part III. Products From Nontraditional Crops Forage is another potential use lion-dollar newsprint mills) or smaller for kenaf. USDA and university fiber projects (producing poultry litter researchers in Oklahoma are testing and twine products). The current work kenaf s potential as a possible niche by industry and USDA was triggered forage crop in the Southern Plains. in the late 1970's, when newsprint This would require very different prices were increasing rapidly. Pub- farming practices, growing the crop lishers became interested in develop- for about 60 days and chopping the ing lower cost, domestic sources of immature green crop with conven- fiber for the manufacture of newsprint. tional forage equipment. The potential A process for newsprint manufac- of kenaf as a forage crop is still in the ture that was developed under the research channel, as feeding trials and leadership of USDA led to a small continued nutritional studies are being first printing by the Peoria Journal conducted. Star, Peoria, IL, in 1977. Commercial- scale trials of kenaf newsprint in 1979, Kenaf Newsprint 1981, and 1987 involved publishers, To better understand what is driving farmers, manufacturers, and USDA. the commercialization of this new Results in the pressrooms of some of crop, consider kenaf's potential as a the major newspapers in the United source of fiber for either large-scale States have greatly encouraged further industrial projects (such as multi-mil- work. In particular, the demonstration One of the principal uses for l^enaf is in pulp and paper products, such as newsprint. USDA 92BW0827 New Crops, New Uses, New Markets 95 project led to a full pressroom run by to rural development. the Bakersfield Califomian in 1987 Other efforts to develop kenaf as a and proved kenaf newsprint to be a fiber source for pulp and paper mills market-ready commodity. generally have confronted the same is- Today ' s environmental concerns sues. Therefore, in 1991, most of the demand that chemical use in both kenaf efforts in the United States be- fields and mills be minimal. Kenaf is gan to focus more on developing mar- an annual crop fiber source, grown kets for separated kenaf fiber products with minimum production inputs by made from bast or core. local farmers (thus reducing transpor- tation costs). Its use could serve to re- Processing Methods duce the pressure on forest resources Overseas, the bark and core fibers are in some areas. Kenaf can be turned separated manually either before or af- into pulp for newsprint with lower en- ter retting (soaking in a fetid pond or ergy and bleaching requirements than canal until bacterial action loosens the those for southern pine. In fact, the bast fibers). This age-old technology Kenaf Paper Company in Willacy is dependent upon extremely cheap la- County, TX, has obtained permits al- bor and very lax environmental regu- lowing it to irrigate its fiber crop with lations. Low and cyclical world prices, the treated wastewaters discharged relatively small U.S. markets for im- from its planned chemi-thermo- ported jute, and the inability to sepa- mechanieal newsprint mill. In addi- rate the bast from the core mechani- tion, research studies at USDA's For- cally had combined to dampen interest est Products Laboratory in Madison, in exploring kenaf's potential. How= Wl, indicate that kenaf can be blended ever, major users of imported jute fi- with recycled newspapers to produce bers have initiated and maintained quality newsprint while also alleviat- communication with the kenaf team as ing pressure on local landfills. it works on gaining acceptance by the However, the proposed kenaf/re- newsprint industry. These users repre- cycled newsprint mill in south Texas sent a starting U.S. "niche" market for has been stalled by the combined ef- kenaf s separated and dry -processed fects of a glutted North American fiber products. market for newsprint, the reluctance of Materials handling has been a financial institutions to invest in a new problem with the earlier commercial agro-industry, and conditions in the kenaf newsprint trials, and in 1986 U.S. economy. Public and private de- the Kenaf Demonstration Project (a velopers remain confident that the cooperative activity between USDA project will soon be recognized for its and a task force of private sector contribution as an economically vi- interests that included Kenaf Interna- able, environmentally sound source of tional, Andritz-Sprout-Bauer, Inc., quality newsprint for regional users in Canadian Pacific Forest Products south Texas and northeastern Mexico, Limited, and the Beloit Corporation) as well as for its ability to contribute focused on finding an effective means 96 Part III. Products From Nontraditional Crops of introducing the unseparated kenaf ing stream) and that the core could be fibers to the pulp mill system. discarded. Engineering intuition also The kenaf stalks had to be reduced told him that energy and capital costs by a common hammermill operation had to be reduced if kenaf was to com- in order to "flow" into the pulping pete as a low-price natural fiber.

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