Abstract：
Reducing CO2 emission and energy consumption is crucial for the sustainable management of wastewater treatment plants (WWTPs). In this study, an algal-bacterial aerobic granular sludge (AGS) system was developed for efficient carbon (C) assimilation and nitrogen (N)/phosphorus (P) removal without the need for mechanical aeration. The photosynthetic O2 production by phototrophic organisms maintained the dissolved oxygen (DO) level at 3-4 mg/L in the bulk liquid, and an LED light control system reduced 10-30% of light energy consumption. Results showed that the biomass assimilated 52% of input dissolved total carbon (DTC), and the produced O2 simultaneously facilitated aerobic nitrification and P uptake with the coexisting phototrophs serving as a C fixer and O2 supplier. This resulted in a stably high total N removal of 81 ± 7% and an N assimilation rate of 7.55 mg/(g-MLVSS∙d) with enhanced microbial assimilation and simultaneous nitrification/denitrification. Good P removal of 92-98% was maintained during the test period at a molar ∆P/∆C ratio of 0.36 ± 0.03 and high P release and uptake rates of 10.84 ± 0.41 and 7.18 ± 0.24 mg/(g- MLVSS∙h), respectively. Photosynthetic O2 was more advantageous for N and P removal than mechanical aeration. This proposed system can contribute to a better design and sustainable operation of WWTPs using algal-bacterial AGS.
摘要：
减少CO2排放和能源消耗对于污水处理厂（WWTP）的可持续管理至关重要。在这项研究中,开发了藻类-细菌好氧颗粒污泥（AGS）系统，用于高效的碳（C）同化和氮（N）/磷（P）去除，而无需机械曝气。光养生物的光合O2产量使散装液体中的溶解氧（DO）水平保持在3-4mg/L，和LED灯控制系统减少了10-30%的光能耗。结果表明，生物量吸收了52%的输入溶解总碳(DTC)，产生的O2同时促进了好氧硝化和P的吸收，共存的光养生物充当了C固定剂和O2的供应商。这导致稳定的高总N去除率为81±7％，N同化率为7.55mg/（g-MLVSS·d），同时增强了微生物同化和同步硝化/反硝化。在测试期间，在0.36±0.03的摩尔△P/△C比率和10.84±0.41和7.18±0.24mg/（g-MLVSS·h）的高P释放和吸收速率下，保持了92-98％的良好P去除，分别。光合O2比机械曝气更有利于N和P的去除。所提出的系统可以有助于使用藻类细菌AGS更好地设计和可持续地运行WWTP。
