air_library_technicalbulletins4_pic1Creative Approaches To Cleaning And Purifying Air: The Clean Air Group’s NOx Scrubbers provide the highest removal efficiency available for NOx. Efficiencies of 90% as measured by EPA Method 7, are guaranteed with many on-line systems operating at efficiencies exceeding 99%. CR Clean Air offers various scrubbing technologies for removing
NOx. Depending on the NOx ratio, a simple aqueous sodium hydroxide
solution can be utilized for scrubbing. The by-products formed in the solution
are sodium nitrate and sodium nitrite.

For high NO levels, we offer an alternative scrubbing approach with counter current packed bed absorbers arranged in a single or multiple staged configuration. The first stage uses an
oxidizing agent to oxidize the NO portion of the NOx to NO2 and other oxidized
NOx species. A second stage may be required with use of a reducing solution to
reduce NO2 to N2. This approach can be used for varied NO2/NO ratios.

No exotic or expensive “proprietary” chemicals are required to achieve high levels of NOx removal.

Clean Air Group NOx Scrubbers are used for exhaust gases containing up to 30,000 ppm of NOx, and excess oxygen. Typically, 5 moles of oxygen are required per mole of NOx. The Clean Air Group can supply the NOx Scrubber alone or a complete system including all auxiliary instrumentation and controls.

‘Your company was selected by a panel of experts from industry and government as having developed one of the most significant major technological advancements in the field of environmental control ” – Pollution Engineering Magazine.

High Guaranteed Efficiency: Clean Air Group to guarantees 90% removal; an efficiency which is significantly higher than that offered by other NOx removal systems. The majority of the Clean Air Group’s installations report over 99% efficiency. Many scrubber manufacturers claim high efficiency. Their claims, however, are often based on N02 removal. Since N02 is partially converted to NO, this may be misleading. The Clean Air Group’s efficiency figures are based on total oxides of nitrogen.

air_library_technicalbulletins4_pic2Low Operating And Maintenance Costs: Water alone, or with common low cost alkaline neutralizing chemicals (but without expensive chemicals additives), is used as the scrubbing medium.  Nozzles can be made from fiberglass or a variety of alloy metals. The scrubber has no moving parts or high-velocity areas, eliminating the need for replacement parts.

The Clean Air Group’s Quality: The Clean Air Group has supplied the process industries with quality products for over 70 years; thousands of Clean Air systems are in service, both in the United States and abroad. Each system is thoroughly tested before shipment, and guaranteed to operate at design specifications. Clean Air Group’s engineers design each NOx system to meet exact customer requirements, insuring efficient service.

Applications: Clean Air Group’s NOx Scrubbers have proven themselves in a variety of applications where they have consistently exceeded performance guarantees.

air_library_technicalbulletins4_pic4Installed for a metal plating application, two model 60T-9H scrubbers in series, were used to treat a 4000 cfm gas stream at ambient temperature, significantly reducing NOx emissions from a pickling process.

In a nitration process, 800 cfm of exhaust air at ambient temperature contained 2000 ppm of NOx as measured by EPA Method 7. Amodel24T-9H NOx Scrubber reduced NOx concentration to less than 100 ppm (an efficiency higher than 95%). The scrubber system also produced 36 gallons per hour of 5% by weight nitric acid for reuse. The Clean Air Group representative in your area is available to discuss your NOx emission problems, and to assist with the selection of proper equipment.

How Clean Air Group’s NOx Fume Scrubber Works: Operation. Exhaust gas containing NOx enters at the scrubber base, as shown in the schematic drawing. The NOx is absorbed as the gas passes upwards. As the intermediate oxide of nitrogen is formed it oxidizes very slowly, determining the NOx removal efficiency. The surface of the mesh retains the intermediate oxide until it is reabsorbed into the scrubbing solution. Otherwise, a portion of the incoming N02 would be released as NO and eventually oxidized hack to N02 Scrubbing solution is sprayed downwards over the packing from the distribution nozzle. The mist eliminator prevents carry-over of scrubber water. The cleaned exhaust gas exits at the top of the scrubber.

Approximate Dimensions: The dimension chart provides approximate dimensions, connections, water and air flows for each scrubber model number. Approved drawings for construction purposes will be provided by the Clean Air Group at the time of purchase.

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