Air Contact Products

Source: Global Odor Control
Air Contact or "atomization" products must make contact with the odorous gases to perform the act of deodorization.
Air Contact or "atomization" products must make contact with the odorous gases to perform the act of deodorization. There are many gases which attain nuisance levels at a few parts per million. In fact, the vast majority of all odor problems involve total pollutant levels of a hundred parts per million or less. Consequently, to achieve success with atomization two factors must be correct. The deodorization product used must be capable of reacting with the odorous gases. And the equipment used must provide the best chance of placing the molecules of the deodorizer in contact with the molecules of the odorous gas or gases.

In exhaust stacks or collection chambers sufficient product may be atomized into the contained area based on the calculated air flow passing through or being collected during any given time interval. In the open air this is not so easily accomplished. In theory, delivering atomized particles of deodorizer as small and light as possible will send them along the same paths as the odorous gas molecules they are trying to contact. In practice, different gases have different molecular weights. Some rise rapidly and glide away for miles. Some hover near the ground and slowly leave the site. Since the deodorizer cannot change molecular weight to match up with a given odor, different deodorizers and reactants must be used in open-air situations to increase the opportunity for contact with different odorous gases. Identification of the gases involved helps to determine desired nozzle and particle size as well as desired deodorizer density and weight.

GOCT offers and recommends low pressure, hydraulic atomization systems for most perimeter applications. The standard set up parameters for these systems are nozzles at 6 meter intervals and 3 to 4 meters (above ground) height. These systems will operate at 240 psi (pounds per square inch) of pressure or less. The typical nozzle implemented will have a capacity of no more than 2.7 liters per hour at continuous operation.

In situations with heavier gases or where humidity and temperature inversions keep odors closer to the ground and dispersing more slowly, larger particle size nozzles spaced at 2 to 3 meter intervals and 1 to 1.5 meter heights may be required. Typical nozzles for these situations should have capacities of 4 to 6 liters per hour at continuous operation. In these situations dilution rates should be 1.5 to 1.6 times those for standard atomizing nozzles.

In smaller interior applications where ceilings are lower than 7 meters, and in exhaust stacks or treatment chambers, the use of compressed air instead of hydraulic power is recommended to power the nozzles. While the deodorizers are still diluted with water, the atomized mist produced by the compressed air is finer and "dryer" than that produced by the hydraulic system. Dilution rates with these systems will be 1.25 to 1.75 times the rates listed for standard parameter hydraulics depending on the size of the compressor implemented. Systems are available from GOCT complete with compressor and motor. Additionally, various controllers and nozzles for use with existing compressors are also available.

Global Odor Control, 4901 N. Mt. Gilead Rd, Bloomington,, IN 47408. Tel: 812- 336- 3435; Fax: 812- 336- 3450.