Venturi/Impinjet® Combination Scrubber Removes HCI & Particulate from Aluminum Refining Furnace Exhaust
A combination Venturi scrubber / Impinjet® scrubber contains stack emissions to 99.999% efficiency from two aluminum furnaces and a small refining station at this aluminum plant.
The scrubber system removes both hydrochloric acid vapors and particulate from the nitrogen gas streams vented from the furnaces. Acid vapors and particulates are evolved when salts are injected into the molten aluminum to clean and de-gasify it.
The scrubber system receives hot gases, which may be as hot as 1650°F, from the furnaces and contacts the gas with atomized scrubbing solution in the Venturi. The Venturi removes the majority of the particulate and the acid gases. In addition, the gas stream temperature is lowered to approximately 120°F.
The acidic scrubbing solution drains into tanks where it is neutralized. Most of the neutralized solution is recirculated back to the Venturi scrubber, however, a small portion is discharged continuously to an effluent treatment plant.
Coupled to the Venturi is a Sly Impinjet gas scrubber. It acts as a final polishing stage for acid gas removal. The scrubbed flue gases are then vented to the atmosphere through a tall stack.