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The problem of coal-water fuel ignition of particles in a high-temperature heating has been solved numerically in the framework of a two-layer model of "coal-water". The basic characteristics of the integrated ignition has been shown. The influence of the vaporization process of the water film on the ignition conditions has been shown. [ABSTRACT FROM AUTHOR]

To converge the conditions of organic water-coal fuel composition combustion in the typical power equipment we developed a new approach and installed an experimental setup, eliminating the traditional fixing the fuel droplets on the thermocouples or rods. Specialized cone-shaped chamber was used to implement the process of lingering of organic water-coal fuel droplets. Necessary and sufficient conditions for the lingering of organic water-coal fuel droplets were established. We determined the parameters of the system (droplet size of 0.4-0.6 mm, temperatures 823-903 K and the velocity of the oxidizer flow 1.5-6 m/s) at which the droplets were consistently ignited in the process of lingering. Minimum temperatures and ignition delay times of organic water-coal fuel droplets based on brown coal, used motor, turbine, transformer oils, kerosene, gasoline and water were defined. [ABSTRACT FROM AUTHOR]

In this work we have reviewed the most of known investigations of the initialization of combustion processes of water-coal fuels. The main problems of such study were emphasized. The definitive effects and factors (like mixing ratio, milling quality, the temperature of the oxidant, properties of the components and methods of the slurry preparation etc.) which have strong influence on inertia and stability of the ignition were analyzed. [ABSTRACT FROM AUTHOR]

To use widespreadly the waste of coals and oils processing in the great and the small-scale power generation, the key parameter, which is sectional constancy of promising organic coal-water fuels (OCWF), was studied. The compositions of OCWF from brown and bituminous coals, filter cakes, used motor, turbine and dielectrical oils, water-oil emulsion and special wetting agent (plasticizer) were investigated. Two modes of preparation were considered. They are with homogenizer and cavitator. It was established that the constancy did not exceed 5-7 days for the compositions of OCWF with brown coals, and 12-15 days for that compositions with bituminous coals and filter cakes. The injection of used oils in a composition of OCWF led to increase in viscosity of fuel compositions and their sectional constancy. [ABSTRACT FROM AUTHOR]

The problem of the particle ignition of coal-water fuel (CWF) with a joint course of the main processes of a thermal (thermal conductivity, evaporation, filtration heat and mass transfer, thermal decomposition of the organic part) has been solved. According to the results of numerical simulation ways of describing the extent of the influence of the thermophysical properties on the characteristics and conditions of ignition WCF have been set. [ABSTRACT FROM AUTHOR]

The problem of particle ignition coal-water fuel (WCF), located in the high-flow environment has been solved numerically. The flow of the main processes of joint thermal treatment (thermal conductivity, evaporation, thermal decomposition, chemical reaction of vapor and carbon) has been taken into account. Set the scale effect of the concentration of the organic portion of the fuel on the dynamics of particle ignition of fuel. The obtained results ignition delay time values are coordinated well with published experimental data. [ABSTRACT FROM AUTHOR]