Criterion's facility in Azusa, CA installed a Tri-NOx Mult-Chem scrubber with a 3000 cfm capacity at 250 lbs./hr. of NOx. The system has four polypropylene columns, three of which form the scrubbing portion of the system and use Tri-Packs column packing. A stainless steel quenching column cools catalyst process offgases from 500 to 150° F.
The scrubber uses an irreversible process involving proprietary solutions and chemistries. Residence time of NOx is minimal, based on the high NOx loading relative to the NO/NO2 ratio. The system operates at greater than 99% efficiency on both NO and NO2 and the stack is clean. No harmful liquid byproducts are generated by the system: the only liquid effluent contains a small amount of soluble salt that is processed by the facility's waste treatment system.