EFFECTIVENESS OF PHOSPHORUS REMOVAL IN AN SBR USING CO-PRECIPITATION WITH FERRIC CHLORIDE, AND ITS EFFECTS ON MICROBIAL ACTIVITY

Brazilian Journal of Chemical Engineering

关键词: Phosphorus removal;    Co-precipitation;    SBR;    Ferric chloride;    Microbial activity;   

DOI  :  10.1590/0104-6632.20190362s20180378

来源: DOAJ

【 摘 要 】

Abstract The present study evaluated the phosphorus removal in a Sequencing Batch Reactor (SBR - 2,500L) used to treat the wastewater from an office building in two steps: phase I-Enhanced biological phosphorus removal (EBPR) and phase II-co-precipitation using FeCl3 as precipitant. The raw sewage presented a high organic load variation ranging from 0.11 (phase I) to 0.66 (phase II) kgCOD.m-3.d-1. A better phosphorus removal performance was obtained during co-precipitation (from 19.0 to 1.2 mg.L-1 = 93% of efficiency) compared with biological removal (from 15.6 to 9.0 mgL-1 = 42% of efficiency). FISH analyses did not demonstrate a strong PAO inhibition; however, nitrifying and denitrifying organisms (NSO and PAE) showed a significant activity reduction during phase II. Therefore, the bench tests made to obtain the oxygen uptake rate (OUR) revealed a heterotrophic organisms activity significantly lower in phase II (46.8 mgDQOT.L-1) than phase I (211.8 mgDQOT.L-1), indicating metabolic inhibition. The co-precipitation processes enhanced phosphorus removal, bringing the SBR effluent into accord with state law requirements; however, the inhibitory effect of ferric chloride on microorganism activity was highlighted.

【 授权许可】

Unknown