Use of a pseudoliquid bed for heat and chemicothermal treatment

The influence of the gas-distributing grid diameter on the transition velocity and hydrodynamics of the bottom layer in circulating fluidized bed installations

“…When two ascending bubbles merge with each other, the velocity of the lower overtaking bubble increases with respect to particles by almost a factor of 2 as it enters in the wake zone of the upper (overtaken) bubble (the diam eter of this zone is approximately equal to 1.2D bub , and the absolute velocity increases in this case to u a = u = u mf + 2u bub ) because the velocity of material particles in the wake zone is close to u bub . At fluidization veloc ities u > u c large bubbles may also disintegrate into smaller ones, a phenomenon the authors observed in experiments carried out on transparent models [8]. In [9], pressure fluctuations in the bed occurring during the transition from a bubble to turbulent mode were modeled in installations fitted with a large diameter grid (D >> D bub ).…”

“…2), which are grouped for narrow intervals of the Ar num ber. The majority of experimental points (1,2,8,9,10,11,13,14) were obtained in installations with D ≤ 0.3 m. Of these, the velocity u c of particle group (2) increases with increasing the diameter; the same of particle groups (1,8,9,11,13,14) decreases, and the velocity of particle group (10) varies in different directions. The other points were obtained for D > 0.3 m. Of them, u c of one group (4) varies in different directions with increasing the diameter; in group (5) u c remains almost unchanged, and in three groups (6, 7, and 12) it decreases.…”

An ecologically pure process of rapid oxide coating (technology, equipment)

“…The positive results of the study allowed us to design, build and install an industrial electric furnace with a fluidized layer for steam oxide coating of powder parts [4,5]. The technical characteristics of the bath furnace are given below.…”

“…The use of a fluidized layer provides a considerable intensification o f the process of steam oxide coating due to the possibility of an accelerated heating (in the fluidized bed, the heat-transfer coefficient is several times higher than in convective heat transfer) and an intense mass transfer; the particles o f the finegrain material "transport" steam molecules, permanently enriching the gaseous medium of the surface of the processed parts [5,6]. The suspension with the parts is loaded into the furnace with the help of a telpher.…”

Use of a pseudo-liquefied layer as an ecologically safe cooling medium

“…The tank for isothermal cooling was a shaft furnace where the boiling layer was placed in a heat-resistant converter made of steel Kh 18N9T and equipped on the bottom with a gas-distributing cap grate [7]. The tank for isothermal cooling was a shaft furnace where the boiling layer was placed in a heat-resistant converter made of steel Kh 18N9T and equipped on the bottom with a gas-distributing cap grate [7].…”