Peracetic Acid vs. Chlorine and Caustic in an Industrial Air Scrubber

Peracetic acid (PAA) was evaluated against chlorine and caustic in a 60,000 cfm air scrubber at California Spray Dry, a large animal rendering plant located in Stockton CA. The air scrubber had been treated with chlorine and sodium hydroxide in order to remove as much odor causing compounds as possible. Though the scrubber treatment was kept under very good control, daily odor complaints from the local community persisted. Also, operation and maintenance on the scrubbers was burdensome due to scale precipitation caused by the high pH water. Peracetic acid (PAA) was tested in order to determine the relative effectiveness of PAA vs. chlorine and caustic. The PAA performed much better as it removed both sulfide and ammonia in a single stage and kept the scrubber clean so that weekly acid washing was no longer necessary.