화학공학소재연구정보센터
Oil Shale, Vol.11, No.3, 227-239, 1994
INTENSIFICATION OF DISTILLATION PROCESS OF DISPERSE SYSTEMS FORMED AT OIL-SHALE THERMAL DISSOLUTION
Thermal dissolution of oil shales yields a mixture of high-boiling liquid products with the solid phase (benzene-soluble compounds), which consists of unreacted organic matter, mineral part and coke-like particles (Table 1). A separation of such a suspension (slurry) by distillation is hindered due to the formation of strong inter- and intramolecular interaction bonds (Fig. 1). The effectiveness of slurry processing may be increased basing on the principles of physicochemical mechanics of disperse systems. In the case studied slurry was taken for a disperse system consisting of a disperse phase (aggregates, associates) and a disperse medium. The aggregates are represented by fine disperse particles of the unreacted organic matter, mineral matter and coke-like particles, and asphaltenes constitute the base of associates. The disperse medium includes mainly oils and tars. The distillation process was intensified by activating substances, intensive mixing and using of counterflow (Tables 2-4; Figs. 2-4). These measures led to decrease of surface tension in the boundary line of ''vapour-liquid'' phases and increased the yield of liquid products. Extracts of selective treatment of oil fractions and pyrolysis tars proved to be the most effective activating admixtures. Distillation in the flow of an evaporating agent (nitrogen, superheated water vapour) in the apparatus equipped with plates with mobile scrapers yields under optimal conditions an ash residue which has a satisfactory complex of properties of a binding material. These shale-derived binding materials can be used as roadway coverings and as roadbed. High-quality sand and ballast asphalt can be produced on their basis as well (Tables 5, 6).