不同C/P下AOA-SBR工艺磷形态转化规律及污泥特性

采用5组厌氧/好氧/缺氧(AOA)模式运行的SBR反应器, 考察不同C/P(120, 40, 24, 17, 13)下AOA-SBR系统磷形态转化规律及污泥特性.结果表明, 5组反应器的COD、TN、NH₄⁺-N去除效果均优于一级A标准.随着C/P的降低, 系统TP去除量逐渐提高.C/P小于24时, TP的去除效果开始变差且波动剧烈, 在C/P为40时系统TP去除效果最稳定, 平均去除率为99.22%.磷形态结果表明, 随着C/P的降低, 污泥中各项磷形态含量均有所升高.IP是TP最主要的磷形态, 不同C/P下IP占TP的含量相近(约96%).随着C/P的降低, NAIP、AP占污泥TP的含量与IP都呈先上升后下降的趋势, 而OP占污泥TP的含量保持下降趋势.生物有效磷(NAIP与OP之和)对污水除磷效果影响最大, C/P为40的系统中污泥中生物有效磷占比最高, 污水TP去除效果最好.污泥MLSS与SVI值随着C/P的降低而增大, C/P较低的系统有发生污泥膨胀的风险.高通量测序表明, 随着C/P的降低, 除Dechloromonas外, PAOs与DPB含量均有所下降, 污水TP去除效果较差且波动较大.

Phosphorus morphology transformation law and sludge characteristics of AOA-SBR process under different C/P

Five groups of SBR reactors operating in anaerobic, aerobic, anoxic(AOA) mode were used to investigate the transformation rules of phosphorus morphology and sludge characteristics of AOA-SBR system under different C/P(120, 40, 24, 17, 13). The results showed that the removal effect of COD, TN and NH₄⁺-N all outperformed the primary A standard. As the C/P decreased, the system TP removal gradually increased. When the C/P was less than 24, the removal effect of the TP began to deteriorate and fluctuate violently. When the C/P was 40, the system was the most stable, with an average removal rate of 99.22%. The results showed that with the decrease of C/P, the phosphorus forms in the sludge increased. IP was the main phosphorus form of TP, and IP was similar under different C/P (about 96%). As C/P decreased, the content of sludge TP and IP decreased, while OP content of sludge TP maintained a downward trend. Biological effective phosphorus (the sum of NAIP and OP) had the greatest impact on sewage phosphorus removal effect, with the highest proportion of bioeffective phosphorus in the sludge with C/P 40, and the best sewage TP removal effect. MLSS and SVI increased with C/P, while the risk of sludge expansion the lower C/P systems. High-throughput sequencing showed that with the decrease of C/P, both PAOs and DPB content decreased except for Dechloromonas, and the sewage TP removal effect was poor and fluctuated greatly.