Half of all trees harvested are chipped up for the paper mills [1]. Half of all landfills are composed of paper products. The purpose of resource substitutes is to begin producing pulp for paper from alternative sources such as the whole stalks of hemp and agricultural waste, or even using no wood products at all, so that our trees may be spared from being converted to landfill. There are plenty of alternative sources of cellulose for paper pulp, many of which produce paper of finer grades than is possible by wood pulp alone. The challenge is to have the right combination of available alternative pulp sources [2] to produce paper of high quality, quality that one can profitably market at competitive prices with the established industry. Many institutions [3] are involved in doing research on these matters.
There are a great variety of possible sources of cellulose for paper pulp, and they may be grouped into two categories. The first category is fiber sources that can be cultivated for the fiber as a primary crop, as in fiber hemp, and kenaf [4] (hibiscus cannabinus- a fiber crop [5] up to three meters high). Both plants are fast-growing annuals that produce enormous quantities of high quality bast fiber in a single season. Both plants also have woody stems that may be processed into pulp [6] of lower quality. The second category is fiber sources whose products can be recycled from agricultural or industrial waste, everything from wheat straw to sunflower stalks, to scraps from the garment industry, to rags and cellulose discards that have been recycled from other sources. Even scrap tires [7] can be used as construction material for building houses. The two following examples may illustrate the challenges and the possibilities of using resource substitutes.
The first example is hemp [8] (Cannabis sativa). Recently hemp has become an excellent source of biomass for alternative fuels [9], as a substitute for petrochemicals [10] in the manufacture of some plastics, and in the manufacture of particle board, fiberboard, and other composites [11] used in the construction industry. The implications of switching from wood to hemp fiber are immense. The fiberboard industry representatives claim that they can make anything that can be made out of a tree, out of hemp. In addition using hemp is more cost effective, and has less of a negative impact on the environment. Hemp is an annual crop grown on existing farmland, eliminating the need to build and reclaim expensive logging roads, or to clear cut vast areas of forest using heavy equipment that damages the ecosystem and reduces biodiversity. Hemp fibers are ideal for producing superior quality paper [12], since the long and light-colored fibers require less bleaching than wood pulp. This results in the production of lower levels of organochlorines (Draper, 1998: 318). With the potential of hemp to become an internationally significant alternative fiber source, it could greatly reduce harvesting pressures on the remaining old growth forests in Canada. "The forest industry could then focus on sustainable forest management, value-added production, and community health and sustainability" (Draper, 1998: 318).
However, there is a negative side. Hemp fiber has been reported to be difficult to pulp and bleach. The difficulty appears to be due to the peculiar physical and chemical nature of the lignin present. However, it is thought that after an initial period of research and development, difficulties of this sort will be worked out. It is thought that eventually more information will lead to an efficient and well-capitalized commercial venture, and offer alternative fiber papers of superior quality and at prices less expensive than wood-based paper.
The second example of an alternative resource is wheat straw . Stacking straw-bales like bricks constructs the walls of a straw-bale home, with staggered joints. The bales are pinned with rebar [13] and wooden dowels. The walls are covered with plaster on the inside and stucco on the outside to create a thick, truly insulated structure. The energy efficiency of a straw-bale home far exceeds any conventional construction method with dramatic energy savings. The energy benefits of straw-bale homes [14] include energy savings and the re-use of a waste product burned in many areas of the world. Straw-bales are one of the only truly sustainable building materials that can be grown in one year.
The Ryan Development Company [15] has been investing in the innovations of today for a future of possibilities. For example, their product, Agriboards [16] is made by heating and compressing straw into a thick fiberboard. No toxic chemicals are used in the process. The board is then encased in a panel of oriented strand board and custom made to fit needed residential or commercial plans [17]. The panels are then set into place with a crane [18] in only days instead of weeks. This system reduces the amount of framing lumber required for a building by eighty percent. Rising lumber prices and concerns about dwindling forests have led to a demand for alternative building materials. Agriboard provides exceptional strength, firm resistance, sound insulation and energy efficiency. Thus the product is good for the farmer, the builder, the consumer, and the environment [19].
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