Description
The packed tower scrubbing system is designed to treat up to 44 000 m3/h of exhaust air extracted from the various processes and the general interior of the buildings where pickle is produced and packed.
The air is ducted to an exhaust fan from which it enters the base of the scrubbing tower, passing upwards through a bed of packing media. This provides the maximum level of surface area for direct contact between the contaminated air and a scrubbing liquor which absorbs odorous contaminants. The scrubbing liquor, a dilute alkaline solution of sodium hypochlorite, is recirculated by a recycle pump from an integral tank at the base of the scrubber to the top of the tower where, evenly distributed by water sprays, it flows downwards through the packing media.
The dosing rate of sodium hypochlorite is controlled by the Redox potential of the scrubbing liquor, and to ensure that the odorous gases are fully absorbed, it is necessary that the solution is alkaline - a condition maintained by a pH controller which regulates the dosing of sodium hydroxide solution.
To improve efficiency the scrubbing liquor passes through an Odorgard ® Catalyst bed.
Before being vented to atmosphere via a stack, clean air passes through a demister at the top of the scrubber to reduce carry over of liquor droplets.
Project Details
Client: Major European Food Company, Derbyshire, England
Industry: Food Processing
Application: Odour Control Scrubber to treat of exhaust air from a food processing plant
