40 CFR 60.211 - Definitions.
(a)Superphosphoric acid plant means any facility that concentrates wet-process phosphoric acid to 66 percent or greater P2O5 content by weight for eventual consumption as a fertilizer. A superphosphoric acid plant includes: evaporators, hot wells, acid sumps, oxidation reactors, and cooling tanks. An oxidation reactor includes any equipment or step that uses an oxidizing agent (e.g., nitric acid, ammonium nitrate, or potassium permanganate) to treat superphosphoric acid.
(c)Equivalent P2O5feed means the quantity of phosphorus, expressed as phosphorus pentoxide, fed to the process.