The Interaction Between the Pressure Loss of Gas and the Flow of a Medium in a Moving Granular Bed Filter

Abstract

A problem was encountered in the application of a moving granular bed filter to the collection of dust contained in the top gas of a blast furnace, where the pressure loss of gas becomes unstable and creates a rapid increase at the elevated gas velocity.
The relationship between dust collection and the pressure loss of gas was simulated. Then, using a half-size precise model, the condition in which the medium flows was examined and related to the pressure gradient of gas.
The increase in pressure loss was presented schematically in the following process: When the gas velocity was raised and the pressure gradient of gas exceeded the critical value, the flow of medium in the bed stalled along the discharging side of gas. The dust accumulated in the stalled medium raised the pressure gradient of gas further. The sequence of these events accelerated the increase in the pressure loss and finally resulted in a serious increase.