Method for recycling rubber-containing wastes

Abstract

The inventive method includes thermal liquefaction of wastes in an organic solvent at a temperature above 270° C. and a pressure up to 6 MPa. The liquid fraction is separated from the undissolved product. The liquid fraction is distilled into the fraction with the boiling temperature below 220° C. and the fraction with the boiling temperature above 220° C. Alkyl benzene or the gasoline fraction with a boiling temperature below 220° C. is used as an organic solvent at the start-up of the process. Thermal liquefaction of a batch of wastes is carried out in an organic solvent at a temperature from 280° C. to 435° C. and a pressure at least 2.9 MPa, the organic solvent-waste weight ratio being more than 1.0. The liquid fraction with the boiling temperature below 220° C. is subjected to catalytic reforming. A part of the liquid fraction, as subjected to catalytic reforming, with the boiling temperature below 220° C. is used as the target product, and the remaining part of the liquid fraction, as subjected to catalytic reforming, with the boiling temperature below 220° C. is used as a solvent and returned for thermal liquefaction of a new batch of wastes at a temperature from 280° C. to 435° C. and a pressure at least 2.9 MPa, the solvent-waste weight ratio being more than 1.0. The process of thermal liquefaction is continued in the said conditions of thermal liquefaction and catalytic reforming for the next and subsequent batches of wastes, while a part of the liquid fraction, as subjected to catalytic reforming, with the boiling temperature below 220° C. being returned for thermal liquefaction.

Description

FIELD OF THE INVENTION [0001] This invention relates to disposal in the chemical industry of organic industrial and household rubber wastes and their processing into motor fuel and chemical stock to be further used as a boiler fuel, a bituminous-like binder or stock for production thereof, technical carbon or stock for production thereof, for electric arc furnaces, electrolysis baths, carbon-carbonic materials (CCM) for metallurgy, etc, as well as a small quantity of hydrocarbon gas which may be used as a fuel. PRIOR ART [0002] The problem of chemical processing of various organic industrial and household polymeric wastes is very actual due to continuous increase in their quantities and pollution of the environment. [0003] Removal of this problem will enable to solve the ecological task of complex and harmless disposal of rubber-containing industrial and household wastes, expand the base of hydrocarbon stock produced from oil, coals, shale coals, natural bitumen. [0004] A method for...

AI Technical Summary

Benefits of technology

[0020] This invention is based on the task of creating a method for recycling rubber-containing wastes, which would enable to accelerate the process and simplify the technology, improve the process productivity as to the yield of a high-octane gasoline fraction and to produce technical carbon as a commercial product, and, thus, lower the power intensity, expand the functional capabilities and raise the quality of the products while lowering the operating costs.

[0036] Thus, in contrast to known methods, the process of waste thermal liquefaction is carried out with the use of an organic solvent produced by the very thermal liquefaction process, wherein, for the purpose of activating subsequent batches of wastes, the light fraction with a boiling temperature below 220° C., which is produced in a thermal liquefaction reactor in the result of distillation, is subjected to reforming before using it as the organic solvent for thermal liquefaction of the next batch of wastes. Thus, the need in a deficit organic solvent for thermal liquefaction of subsequent batches of wastes, as well as in other thermolysis activators, e.g., rare-earth metals, intermetallics, titanium hydride, etc., is eliminated completely.

Problems solved by technology

The problem of chemical processing of various organic industrial and household polymeric wastes is very actual due to continuous increase in their quantities and pollution of the environment.

A limitation of the said method is the use of wastes from the synthetic rubber production, since such wastes are not always available in the required quantity.

A limitation of the said method is its high energy intensity due to using, as a part of the solvent, the liquid fraction with the boiling temperature not less than 210° C., and high operation pressures exceeding 6.1 MPa.

Some limitations of the said method are:

for efficient thermal liquefaction (thermolysis) the process is carried out in the presence of a rare-earth metal or intermetallics based on rare-earth metals or in the presence which are taken in the amount of 0.5% to 10% of the reaction mixture weight, which complicates the production process, and, moreover, removal of these additional catalysts and additives from the resulting valuable target product, namely, technical carbon, is very complicated;

low quality of technical carbon due to big amounts of ash materials, which is a consequence of using additives together with a solvent;

a high consumption rate of a solvent when producing a high-quality gasoline fraction.

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