Scrubber Air Pollution Control

The system used to prevent acid gases and heavy metals from being discharged to the atmosphere is called an Air Pollution Control System (Scrubber). The Scrubber is attached to the Oxidizer system through a T-section in the exhaust stack from the Afterburner.

The Scrubber incorporated the use of water, a neutralizing chemical and fine, Teflon plastic fibres to clean the exhaust gas from burning garbage. The industry typically refers to this type of system as a Wet Scrubber. Due to the very low emission levels of the Oxidizer system, a baghouse is not required to filter solid material in the exhaust gas stream.

Step 1
Water is used to cool hot gases from the Oxidizer very rapidly. Gases enter the Scrubber at approx. 1800F, and are cooled by use of water sprays. At this stage, heavy metals in the form of a vapour will solidify and be collected in a water discharge tank.

Step 2
After cooling, the gases enter into a packed tower where they are sprayed with a solution of sodium hydroxide and water. This solution causes a reaction to change the acid gases into salt and water.

Step 3
The neutralized gases are drawn out to the atmosphere. Due to the high moisture content a white plume of steam will be visible from the Scrubber exhaust stack.

Step 4
The water that contains the pollutant materials is held in a discharge tank for release to the sanitary sewer system or for further treatment if a sanitary sewer is not available.

Operating Costs:
Approximately $0.01 per pound of material processed.

Typical usage is approximately 8 gallons of sodium hydroxide per ton of medical waste (used as a neutralizer for acid gases) depending on plastic content in waste.

Eco Waste Solutions Inc., 5195 Harvester Road, Unit 6, Burlington, ON L7L 6E9. Tel: 905-634-7022; Fax: 905-634-0831.