CR CleanAir patented NOx scrubbing technology provides extremely high removal efficiencies (90 – 99%) for total NOx (NO2 and NO) without the need for exotic or expensive “proprietary” chemicals. This technology is not applicable to combustion generated NOx.
Our Surface Active packing media makes these high efficiencies possible by retaining intermediate aqueous reaction products on its surface long enough to permit their absorption. Thus preventing these reaction products from breaking down to form NO which would otherwise be released back into the gas stream. It is this re-release of NO into the gas stream that limits the efficiency of conventional water or caustic scrubbing to less than 70%.
Typically a simple aqueous sodium hydroxide solution is utilized for scrubbing. The by-products formed in the solution are sodium nitrate and sodium nitrite. Due to the construction material required for the Surface Active Media any chlorides, fluorides, or other compounds that would attack a 300 series stainless steel material must be pre-scrubbed from the gas stream upstream of the NOx scrubber.
There are three sets of inlet gas parameter which define the range of practical suitability for the The Clean Air Group, LLC patented technology.
Oxidizing/Reducing Technology for combustion related NOx: For applications that are not suitable for CR CleanAir, LLC proprietary technology, we can generally offer an alternative scrubbing approach. The alternate would also utilize counter current packed bed absorbers but in a multiple staged configuration. The first stage would use an oxidizing scrubbing solution to oxidize the NO portion of the NOx to NO2. The second stage would use a reducing solution to reduce the NO2 to N2. This technology can be successfully used for varied NO2/NO ratios.