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An experimental investigation has been conducted into combined hydrothermal fluidized carbonization of poultry litter and sawdust in a superheated steam medium. The effects of temperature on the duration of the process of hydrothermal carbonization have been identified, and the composition of the noncondensable gaseous products of carbonization has been established. [ABSTRACT FROM AUTHOR]

Experimental investigation of the radial distributions of tangential air velocity and total pressure in the vortex overbed zone of a fluidized bed of diameter 0.393 m has been carried out. The influence of the entrainment of particles from the bed in the exhaust trails of gas bubbles on the maximum values of tangential velocity and total pressure has been established. [ABSTRACT FROM AUTHOR]

The thermal fluidization of quartz sand particles under the action of a constant-power heat source on the upper boundary of a granular bed has been investigated. [ABSTRACT FROM AUTHOR]

The migration of macroparticles in a fluidized bed of a finely divided quartz sand has been studied experimentally. The mechanism underlying the influence of the mixing of fluidized bed particles on the character of macroparticle motion is described. The dependence of the depth of macroparticle immersion on the physical and operational parameters has been obtained. [ABSTRACT FROM AUTHOR]

An experimental study has been made of the entrainment of crushed-corn particles of diameter d = 0.88 mm from a fluidized bed with the vortex organization of an over-bed space. The dependence of the entrainment rate on the characteristics of the fluidized bed and the cyclone chamber has been established. [ABSTRACT FROM AUTHOR]

Radial distributions of the velocity components of particles in a vertical vortex chamber in the presence of axial (bottom) blowing under conditions of quasi-solid rotation are considered, and the dependence of the particle rotation frequency on the Stokes number and the fraction of bottom blowing has been established. [ABSTRACT FROM AUTHOR]

The process of heating a granular bed by filtering air under conditions of the transition of a fixed bed into a bubbling one has been investigated. A dimensionless relation for calculating the time of heating has been obtained. [ABSTRACT FROM AUTHOR]

Within the framework of the two-temperature model, the authors have investigated the dynamics of charging and discharging of a bed of finely dispersed spherical capsules. Generalized dependences have been obtained for calculating the times of charging and discharging of a heat accumulator. [ABSTRACT FROM AUTHOR]

An experimental study of combustion processes in laboratory and pilot plants of various size equipped with cyclone-bed furnaces with a fixed and a fluidized bed and a wide range of solid biofuels was carried out. Numerical simulation of furnace processes in cyclone-bed furnaces was performed using the standard k–ε turbulence model and the Magnussen combustion model. A semiempirical method for calculating cyclone-bed furnaces has been developed. [ABSTRACT FROM AUTHOR]

The problem of the choice of parameters (density, size) of particle inertia for visualization and diagnostics of free vortices of various intensities (characteristic velocity, vortex funnel diameter) is considered. The dimensionless criterion (Stokes number) is used, which determines the peculiarities of solid particles behavior in concentrated vortex structures. An example of the choice of particle parameters for visualization of a laboratory-simulated air vortex funnel and debris cloud is described. [ABSTRACT FROM AUTHOR]

An investigation has been made into accelerated hydrothermal fluidized carbonization of sewage sludge in a superheated steam medium. It is shown that an increase in the process temperature has no effect on its duration but has a significant effect on the composition of noncondensable gases. Biochar activation has been investigated in potassium hydroxide at a temperature of 750°C and the biochar–KOH ratios of 1:1.5, 1:2, and 1:3. It is shown that the KOH concentration has no effect, in practice, on the sorption characteristics of the obtained product which is more suitable for the use as a soil improver. [ABSTRACT FROM AUTHOR]

Fluidization of two types of a bidisperse bed with marked bimodality of particle size distribution has been investigated experimentally. The possibility of using the mixture equivalent diameter is shown provided the latter is calculated by the weighted-mean diameter of the particles composing this mixture. [ABSTRACT FROM AUTHOR]

A study is made of the problem of taking account of the compressibility of the solid phase at high pressures in problems of gas flow through porous media for linear filtration and nonlinear filtration alike. For this purpose, the problems of one-dimensional steady-state gas flow through a porous medium have been solved and analyzed for a compressible and an incompressible solid porous skeleton at a known pressure difference. It has been shown that in taking account of the compressibility, the maximum relative deviations of the sought quantities from the value calculated disregarding it depend linearly, as a rule, on the compressibility factor and the pressure of the gas at entry into the porous medium. However in the case of nonlinear filtration, in media with a high permeability, taking account of the compressibility is also influenced by the filtration coefficient and by the inertial coefficient of drag of the porous medium. Nonlinear dependences of the maximum relative changes in the sought quantities on the problem's parameters arise. [ABSTRACT FROM AUTHOR]