限量曝气进水时间对硝化颗粒污泥的影响特性研究

缺氧-好氧环境的交替循环对氨氧化细菌和亚硝酸盐氧化细菌具有重要影响.本研究通过逐渐增加限量曝气进水时间(从10 min至120 min)延长缺氧时段,考察柱形SBR中硝化颗粒污泥对不同缺氧-好氧环境交替循环的响应特性.整个研究过程中,硝化颗粒污泥保持着稳定的颗粒特征,粒径大于0.8 mm的颗粒污泥占总污泥量的质量分数始终在95%以上,颗粒平均沉降速率维持在125～130 m·h-1之间.尽管缺氧时段不断延长,但NH+4-N去除率和NO-2-N累积率分别稳定在(60±5)%、(85±5)%;此外,在每个周期的曝气反应时段,NH+4-N的去除速率以及NO-2-N和NO-3-N的累积速率分别保持在90mg·(L·h)-1、70 mg·(L·h)-1和15 mg·(L·h)-1左右.以上结果表明,限量进水时间的延长及其所造成的不同时间跨度的缺氧环境对硝化颗粒污泥没有较为显著的影响.

Effects of Anaerobic Feeding Period on Nitrifying Granular

Alternating anoxic/oxic conditions have profound effects on both ammonium (AOB) and nitrite (NOB) oxidizing bacteria. In this study the influence of alternating anoxic/oxic condition on nitrifying granules was evaluated in a laboratory-scale column-type sequencing batch reactor (SBR). The anoxic phase was extended from 10 min to 120 min by increasing the anaerobic feeding time. Granules maintained their structure and characteristics during the whole study. The amount of granules with diameter larger than 0.8 mm kept above 95% (mass fraction), and the average settling velocity of particles maintained in the range of 125-130 m·h^-1. Despite the increase in the length of anoxic phases, the values of ammonium removal and nitrite accumulation in effluent still kept at (60±5)% and (85±5)%, respectively. Moreover, in the aeration period per cycle, NH₄⁺-N removal loading rates, NO₂^--N and NO₃^--N accumulation loading rates retained stably at 90 mg·(L·h)^-1, 70 mg·(L·h)^-1 and 15 mg·(L·h)^-1, respectively. All these results suggested the changing anoxic conditions resulted from prolonged anaerobic feeding period had no significant effects on nitrifying granules.