PHORMIDIUM TREATMENT OF ANAEROBICALLY TREATED SWINE WASTE-WATER

The ability of Phormidium sp. to grow in anaerobically digested swine waste medium and the use of this organism for tertiary biotreatment of wastewater was evaluated. In addition to monitoring the growth of Phormidium, the removal of total phosphorus (total P), orthophosphate (P-PO4), nitrates (N-NO3) and ammonium (N-NH4) were also measured. Dilutions from 50 to 10% of the secondary effluent were tested and results compared with Dauta's medium which was used as a control. Results obtained at 25% dilution in 21. graduated cylinders were: 100% removal of orthophosphate, 87% of nitrate, 68% of total phosphate and 48% of ammonium ion. Removals obtained in a carrousel type reactor were: 48% for orthophosphate, 30% for nitrate, 63% for total phosphorus and 100% for ammonium ion. These removals were higher in both cases than those obtained in Dauta's medium. The total ammonium uptake for the 25% dilution by Phormidium sp. was 7.65 mg/l-d in the glass cylinders and 19.93 mg/l-d in the carrousel reactor.