METHOD FOR PROCESSING BITUMEN-CONTAINING WASTES Russian patent published in 2019 - IPC B09B3/00 

FIELD: waste processing and disposal.

SUBSTANCE: invention relates to the field of waste processing, in particular, to processing and utilization of bitumen-containing wastes. Initial bitumen-containing wastes are cooled to temperature of 10…12 °C and milled. Ground waste is pre-heated to temperature of 60…70 °C and fed into a melting chamber, where it is exposed to hot air at temperature of 160…170 °C. At that, the bitumen melts and flows down to the bottom of the melting chamber into the reservoir for collecting liquid bitumen, and coarse stone crumb settles on the bottom of the vessel. Bitumen is then fed into a separator for cleaning from fine stone crumbs. Pure bitumen is fed into a mixing tank for bitumen, where it is mixed with a modifier at temperature of 140…150 °C. Modifier is prepared in a modifying tank at temperature of 130…140 °C. Ready bitumen is packed into a container and cooled to temperature of 20…30 °C. Bituminized bitumen remaining after melting bitumen is crushed, briquetted and cooled to temperature of 20…30 °C. Large and small stone crumbs are packed and cooled to temperature of 20…30 °C. Fumes of light aromatic hydrocarbons formed during smelting are discharged into a heat exchanger-condenser where condensation of light aromatic hydrocarbons takes place at temperature of 110…120 °C, which are discharged into a mixing tank for bitumen, and cleaned air is discharged into atmosphere. Preparation of energy carriers for implementation of temperature parameters of the method is carried out using a steam compression heat pump, which includes a compressor, a condenser, a temperature control valve and an evaporator, operating in a closed thermodynamic cycle. Working medium used is incombustible, explosion-proof Khladon 21 CHFCl₂ with a boiling point of 8.7 °C and critical temperature of 178.5 °C. Condenser is used for preparation of heat-resistant heat carrier, providing processes of melting wastes, their mixing with modifier and preparation of modifier, and the evaporator is used to cool the air supplied to the waste cooling chamber into the stone crumbstone cooler, into the bitumen cooler, into the heat exchanger-condenser for condensation of light hydrocarbon vapors and into the briquette cooler. Warm air flows are combined into a common warm air flow with temperature of 80…90 °C, which is directed into heating chamber for preliminary heating of ground wastes to temperature of 60…70 °C. Exhaust air from the heating chamber is again combined with the air flow discharged from the cooling chamber for supply to the cyclone, where the air is cleaned of suspended particles and dust. Suspended particles and dust are removed from cyclone for recycling, and clean air – for cooling into evaporator of steam compression heat pump, then cycle is repeated.

EFFECT: invention increases efficiency of processing bituminous wastes with separation into component components, which can be used in making other products, with maximum output of pure bitumen of high quality, as well as reducing emissions of waste heat carriers to atmosphere and reducing fire hazard.

1 cl, 1 dwg