It is known that rubber-base products, such as industrial wastes, and more particularly, tires, represent increasingly large storage volumes and cause serious problems of disposal and profitable use.
Actually, destruction by self-burning in the open air is extremely polluting because of the release of carbon black from the imperfect combustion of hydrocarbons that make up natural and synthetic rubbers. When specialized combustion installations are used, the costs are high because of the high cost of shredding and combustion apparatus.
For a number of years attempts have been made to make profitable use of these wastes in various ways; for example, shredding and grinding to obtain powder products that can be recycled in rubber manufacture or used in soil coverings, or again solubilizing and dissolving in hydrocarbon solvents with further regeneration of the rubber or adhesive products. Another technique, considered as reasonable and, a priori, promising for the future, consists in performing incineration and pyrolysis of the wastes to be able to recover the valuable materials such as carbon black, oils and gaseous products. However, these complex processes of pyrolysis at 500 to 1,000.degree. C. and often under high pressures (for example, 100 bars) are not now developed on an industrial scale, because the recovered products have a lower market value than the treatment cost.
USPTO Backgrounds
USPTO Backgrounds