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Mathematical Modeling of Iron and Steel Making Pocesses. Modelling of Liquid Flow in the Blast Furnace. Theoretical Analysis of the Effects of Gas, Liquid and Packing Properties.

“…For example, the concept of flooding, which is a limiting condition in the operation of a one-dimensional column, must be reanalysed for the non-uniform packed bed of a blast furnace. 12) In the one-dimensional system considered by Fukutake,4) the total holdup determined without gas flow was recalculated as a function of the gas pressure gradient. In simple terms, gas flowing countercurrent to liquid changed the holdup which, in turn, affected the pressure drop due to a change in bed permeability.…”

“…Hence, Fukutake 4) extended Eq. (7) Using an average superficial velocity for gas in the blast furnace lower zone of 1.9 m g 3 · m b Ϫ2 · s…”

“…In the countercurrent system considered by Fukutake, 4) upward flowing gas created drag on liquid to counteract the downward gravity force and therefore increased the capacity of the bed to hold liquid. If a system was considered where gas and liquid flow were co-current, the drag of gas on liquid would be expected to augment the gravity force and therefore decrease the capacity of the bed to hold liquid.…”

“…4) Experiments were performed over an extensive range of conditions relevant to both molten iron and slag flow, providing gas pressure drop and liquid holdup information: modified Capillary, modified Reynold's, modified Galileo and effective Capillary number, respectively, N c and X p are the dimensionless interfacial force and gas pressure drop, respectively, and DP w /DL, r l , g, f, d p , s, e, q, k 1 , k 2 , d l , m g , r g and U og are the wet bed pressure gradient, liquid density, gravity, particle shape factor, particle diameter, surface tension, porosity, contact angle, viscous term Ergun coefficient, inertial term Ergun coefficient, liquid droplet diameter, gas viscosity, gas density and gas superficial velocity, respectively. In this paper, an attempt will be made to quantify the complex interactions between gas, liquid and solid under blast furnace conditions.…”

“…[9][10][11] However, as for liquid holdup, the unique operating characteristics of the blast furnace require careful consideration. Fukutake 4) considered some, but not all of the implications. For example, the concept of flooding, which is a limiting condition in the operation of a one-dimensional column, must be reanalysed for the non-uniform packed bed of a blast furnace.…”