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A study of thermophysical and ecological properties of highly loaded (50% mass.) coal-water slurry based on Kansk-Achinsk brown coal and distilled water (coal-water slurry fuel -CWSF) with exposure of used water to cavitation-treatment, microwave processing of coal powder, T-900 nanocarbon additions is presented. The study shows that under the conditions of this experiment the thermal physical properties of CWSF are most affected by the use of cavitation-activated water.

Among the new coal technologies the burning of low-grade coal in the form of coal-water slurry fuel (CWSF) is of a great interest. The basis of CWSF is a highly concentrated coal-water slurry consisting of finely ground coal, water or other liquid and plasticizing agents. The development of CWSF technology is highly relevant for solving global problems of resource conservation and ecology. The study is dedicated to CWSF properties with respect to Kansk-Achinsk coal and water. This paper presents the results of the influence of CWSF’s preliminary cavitation water treatment on the combustion dynamics of fuel, (including the features of the combustion temperature trends, delayed ignition time and time of complete combustion) and on its environmental characteristics. A rotary-type hydrodynamic oscillator at high angular velocity (10000 rpm) was used in supercavitation mode. It is shown that the technology of cavitation water treatment leads to a change in the dynamics of CWSF’s combustion and to an additional decrease in NOx emissions by 1.6 times, CO2 by 1.3 times.

Changes in the properties of brown Kansk-Achinsk coal after exposure to microwaves have been studied using scanning electron microscopy (SEM) and electron magnetic resonance (EMR). The size composition of the samples has been investigated. The structure of coal has been found to be similar to the structure of multicomponent organic glass. The analysis of the changes in the EMR spectra of the coal samples (300 K, 83 K) exposed to microwaves has been found to gather information about the structural transformation taking place in the coal matter.

Variation of surface tension coefficient σ of distilled water under high-energy impact (hydrodynamic cavitation) was studied by the ring separation method. Force impacts on surface tension of water have been studied experimentally. Conditions have been found under which the surface tension coefficient σ decreases to 20%. The paper explains the produced results on the basis of cluster theory of water structure. The experimentally produced relaxation time of the surface tension of cavitation-activated distilled water to initial value has been found to be 3.5 hours.

Nowadays polymer matrix-based composite material with various carbon fillers are widely used to protect radioequipment from different interference, to improve characteristics of radar absorbing coatings. Current synthesis processes are sophisticated and rather costly. The challenge is to develop new methods of producing composite materials by efficient knowledge intensive technologies to reduce the cost of products. The paper studies possibility of producing composite material on the basis of elastic polyurethane foam with carbon fillers using polyurethane impregnation in nonequilibrium black carbon suspension. Suspension composition: running water and carbon-bearing powders of nanometer range: fullerene black carbon, Taunite (multi-layer carbon nano tube material), technical carbon T900, wood soot. Nonequilibrium suspension was produced by treatment in hydrodynamic generator of rotor type (cavitation mode). Angular rotation speed of the rotor ω = 10000 rpm.

This paper presents analysis of optical images of films obtained by evaporation (293 K) of a thin layer of low-concentrated (1% wt.) aqueous soot suspensions in a Petri dish. Suspensions of wood, fullerene and diamond-containing (after detonation synthesis) soot were prepared using hydrodynamic dispersion in a cavitation mixer with a wedge-shaped cavitator with the rotor’s angular velocity of rotation being 10000 rpm. The components of the hydrodynamic dispersion process are turbulent micro-mixing and bubble cavitation. As a result of intense turbulence, carbon suspensions assumed properties of non-equilibrium systems. The images of an optical microscope revealed self-organized dissipative micron-sized structures in the dried films being present there in the form of chain, branched and ring-shaped cluster fractals of various dimensions that look very similar to nanotubes. The self-assembling effect was identified for all the types of suspensions under study. The EPR method was used to study the change in the electronic structure of soot resulting from the exposure to high temperatures and pressures that occur when the cavitation bubbles collapse (cavitational activation). The dynamics of changes in dissipative structures in the process of film drying was monitored.

Coal-water slurry (CWS) is the basis of modern alternative fuel - coal-water fuel (CWF). To produce stable coal-water slurry, i.e. coagulation and separation is an important technological problem. The paper studies CWS the disperse part of which is fine brown Kansk-Achinsk coal, the dispersive part is distilled water. Effect of cavitational conditioning on CWS stability has been studied. The efficiency was for the first time studied by magnetic resonance tomography (MRT). In the experiment spin-lattice relaxation time profiles T1 were recorded along the central vertical axis of the samples. T1 dynamics correlates well with the local density of CWS solid phase. MRT data was sequentially interpreted with rheological characteristics of CWS. Feasibility of applying MRT method to find out time and space evolution of CWS has been estimated. The MRT methods has been shown to be efficient in resolution of technological problems to improve consumer properties of the coal-water fuel.