Blast Furnace Cast House Dust Collection System

The existing collector was sized for a smaller furnace campaign. During tapping, dust escaped through the cast house roof, bag blinding raised resistance above 2,400 Pa and the fan could not hold the required negative pressure. The plant also faced a short shutdown window for the retrofit.

01Re-measured dust source points at the taphole, runner and slag pit, then redesigned capture hoods and duct routing to shorten the run and balance the pressure drop.
02Sized a new 8-chamber offline pulse baghouse at 6,400 m² filter area with cloth velocity below 1.0 m/min for abrasive cast house dust.
03Selected PTFE membrane filter bags with anti-static treatment and hardened hoppers to extend service life under abrasive load.
04Installed a VFD controlled induced draft fan with pressure feedback so the system follows the tapping cycle instead of running at fixed speed.
05Pre-assembled chambers in the factory and used a modular lifting plan to complete the installation inside the scheduled shutdown.

After commissioning, the cast house roof no longer shows visible emission during tapping, system resistance stays around 1,450 Pa and the fan runs at reduced speed for most of the cycle. Emission values are recorded by the plant CEMS and remain within the site limit, subject to local regulation and actual operating condition.