Phosphorus removal from wastewater by bioaugmented activated sludge with different amounts of natural zeolite addition

摘要

The influence and performance of different amounts of NZ additive in enhanced biological phosphorus removal (EBPR) system with different initial concentration of phosphorus (1-100 mg T-P L~(-1)) were investigated. The efficiency of P-removal was in correlation with the amount of NZ additive used. The improvement of P removal in regards to the EBPR was lower with 0.5 % NZ addition than with 1.5 % NZ addition for each range of starting P load in wastewater. The amount of P removed increased with increasing starting P load. Significant stronger decrease of COD has been achieved in reactors with NZ, and stronger by larger NZ additive used. The application of NZ addition in EBPR process enables increase in sludge concentration (increase of MLSS) in the system and decreased volume of excess sludge (lower SVI). The probable mechanism of P-removal in EBPR system with NZ addition is a combination of adsorption of P onto NZ particles, increased metabolic activity of activated sludge, P uptake by P-accumulating bacteria biosorbed on the NZ particles and suspended in solution.