Long-term effect of low concentration Cr(VI) on P removal in granule-based enhanced biological phosphorus removal (EBPR) system.

摘要: Abstract In light of the fact that most wastewater in China contained both industrial and domestic wastewater, a 52-d systematical investigation was conducted on long-term effect low concentration Cr(VI) (0.3–0.8 mg L−1) P removal performance granule-based EBPR system this study. The mechanisms were likewise discussed. Results showed high (⩾0.5 mg L−1) could significantly inhibit removal, while phenomenon not found when less than (or equal to) 0.4 mg L−1. Most granules disintegrated filamentous bacteria overgrew inducing sludge bulking occurred at 0.7 mg L−1 Cr(VI). During exposure test, abundance poly-phosphate-accumulating organisms (PAOs) decreased populations glycogen accumulating (GAOs) other increased. Both production degradation poly-β-hydroxyakanoates (PHAs) apparently inhibited. An improved polysaccharide/protein (PS/PN) ratio observed with increasing concentration, implying excessive polysaccharide secreted by microorganisms to support its resistance toxicity Besides, good linear regression between PS/PN granule size (R2 = −0.86, p