Trickle Flow Behaviors of Liquid Iron and Molten Slag in the Lower Part of Blast Furnace

Abstract

Synopsis :In-situ observations of the liquid high carbon iron (HCI) and slag flows in the packed coke bed was carried out by using high temperature Xray fluoroscopy at 1773 K. Along with the observation, 2-dimensional multiphase computational simulations of the liquid HCI and slag flows in the coke bed was carried out to investigate the effect of the slag on the HCI flow in the coke bed. It is found that the liquid HCI or slag could not pass through the coke bed with the coke diameter of 3-5 mm, however, the HCI can pass through the same size coke bed if the HCI is contacted with the slag through the X-ray fluoroscopic observation and the computational flow simulation. When the HCI and slag contacted each other on the coke surface, the contact angle of the HCI with slag decreased and the initially non-wettable characteristic of the HCI changed to wettable one. On the other hand, the slag's contact angle is increased and changed to non-wettable. Based on the experimental and simulated results, it is confirmed that the contact angle change due to the HCI-slag contact make it possible for the liquid HCI and slag to pass though the narrow coke slit that is small enough to prevent each liquid's flow down if they are not contacted. Based on the capillary rise model, the driving force of the HCI penetration into the coke bed will be the energy reduction by extending area of the coke surface covered with the liquid HCI.

Capturing the non‐spherical shape of granular media and its trickle flow characteristics using fully‐Lagrangian method

“…Ueda et al investigated the softening, melting, and permeation processes of CaO–FeO–SiO 2 oxide on a coke bed . Jeong et al used X‐ray fluoroscopy to directly observe the coke‐bed passage behavior of hot metal and surveyed the effects of the coke particle size on the flow . They used the capillary length κ −1 = (σ/ρ g ) 1/2 to associate the limiting length for melt passage with the coke particle size.…”