The production of tar pitches and binding agents for the manufacture of high quality carbon materials is considered. The progressive scarcity of coal tar pitch is noted. The necessity of a search for new sources of raw materials and alternative methods for the production of coal tar pitch substitutes is substanti ated. The capabilities of different methods for the thermal and thermochemical processing of coals with the production of pitch like products are considered. The prospects of a low temperature process of the thermal dissolution of coals under mild conditions for the preparation of pitch products in a yield much higher that the yield of pitch upon coking are demonstrated.

The effect of nanoparticles of various chemical components and sizes on the rheological behaviour of drilling fluids, pressure loss and cuttings transport in the vertical borehole for a laminar flow regime is considered in the paper. The results of numerical and experimental studies are presented. Silicon, aluminium and titanium oxides nanoparticles are considered. A drilling fluid is Bentonite-water solution with a mass fraction of 5%. The particles concentration in the solution was varied from 0.25 to 2 weight percentages and the particles sizes ranged from 5 to 50 nm. The dependences of the effective viscosity and rheological parameters of the solutions on the nanoparticles concentrations, sizes and materials were obtained. It was shown that nanoparticles in drilling fluid increase cuttings transport by 17% and decrease the average slip velocity of the sludge particles in 1.7 to 2.0 times, but the pressure losses when pumping the drilling fluid increase in 2.5 times.

The process of thermal dissolution of medium metamorphosed coals in anthracene oil to produce an alternative pitch binder was studied. The process was carried out at temperatures from 350 to 400°C and pressure not higher than 2.5 MPa, without the use of hydrogen and catalysts. It was determined that during thermal dissolution hard coal of gaseous-fat grade demonstrated a higher activity compared with less metamorphosed gaseous coal. Under optimal conditions at a temperature of 350-380°C yields of pitch tar containing product are 63-75%. With regard to their composition and the main technical characteristics the isolated pitches are at the level in the middle between the coal-tar and oil pitches. Based on the yield data analysis, technical and environmental characteristics of the isolated pitch products a conclusion was made on the prospects of thermal dissolution process as an alternative method for preparing extractive pitch-a substitute for coal-tar pitch produced by coking process.

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