Recycling reclaiming fiber

A surprisingly low concentration of water can reduce the viscosity such that reclaimed PET cannot be used for the blow molding of bottles with acceptable physical properties. The established solution to the moisture problem is to dry the recycled PET in special dryers prior to use. However, the drying process is both time and energy intensive. Paper labels can cause problems in PET recycling if they decompose during washing and removal. The paper fibers formed can produce cellulose fibers that are difficult to remove from the reprocessed PET.1... 

In contrast, PET end-use markets have been developing for at least 10 years. When the PET bottle was introduced in 1978 and was collected in states with deposit laws, the industry for recycling them and reusing them began to develop. PET resins can be reused to make polyols for insulation and unsaturated resins for bathtubs, shower stalls, boat hulls, and auto panels. Reclaimed PET is also used for strapping, paint brushes, geotextiles, fibers for fiberfill and carpets, and other textile applications. 

Many recyclable materials consist of mixed materials that pose special problems. Discarded automobile oil filters contain steel, fiber, and contaminated petroleum. Oil filters are crushed and heated to remove oil, and the metal reclaimed. Discarded household appliances contain large amoxmts of steel but must often be dismantled, with other materials removed. A special fee is charged at recycling centers to discard most appliances. Fluorescent lamps contain small amounts of mercury that can be reclaimed. Used computers and television sets contain usable materials and, often, some toxic materials that can be collected for safe disposal. 

Allred RE, Coons AB, Simonson R, Properties of carbon fibers reclaimed from composite manufacturing scrap by tertiary recycling, Proc 28th Int SAMPE Tech Conf, Seattle, Nov 4-7, 1996. 

DuPont is recycling mineral-reinforced nylon 66 carpet, including that generated by Ford Motor Company that contains 25% postconsumer recycled content to manufacture engine air-cleaner housings. A proprietary process is used to reclaim the face fiber, which is melt-recycled and compoimded with virgin nylon. ... 

Remnants of cloth from apparel manufacturing, in particular, are a disposal and cost problem. This is true especially for those that use mixed fiber blends, including those containing spandex fibers. Currently there is no effort to recycle the mixed fiber fabric remnants and use the reclaimed individual fibers. 

There are a variety of WPC products in the market These commerdal products could originate from virgin or recycled polymers and virgin or reclaimed wood. For instance, Andersen Windows Company utilizes waste PVC from their manufacturing plant in producing WPC window components. Certain Teed Company uses recycled fibers in their Boardwalk plastic composites. Some examples of WPC products and their major components are listed in Table 13.4, with a focus on the United States, which has the biggest WPC market for building applications. 

An example along the above lines may be the new solvent-spun fiber Tencel, by Courtaulds, which recently was introduced. It is claimed to have an environmentally clean process, with virtually total recycling of the solvent." The manufacturing process is said to involve the dissolving of pulp in hot amine oxide, filtration of the solution, and then spinning into a bath containing a dilute solution of the solvent. The bath removes the amine oxide from the fibers, which are washed and dried, and the removed solvent is reclaimed for further use. The final fiber is said to have a different molecular structure from that of normal rayon, and a smooth surface and a round cross section. The fiber is claimed to be stronger than cotton and normal rayon in both the dry and the wet states. 

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