Abstract:

In order to explore the optimal conditions of nitrifying sludge granulation, test was carried out in a sequencing batch reactor (SBR) at operation conditions: temperature 28℃, aeration 0.2 m³·h^-1, dissolved oxygen(DO)>2.0 mg·L^-1, sludge age (SRT) 15d, leading to settling time shorten to 2min. The granulation of nitrifying floccular activated sludge was achieved successfully after 80 stable cycles (19d) by parameter control of ammonia oxidation process, by optimization of aerobic time and against over-aeration, and average diameter of sludge granular obtained was between 1.5—2.0 mm. The efficiency of COD and ammonia removal was 80% and 95%, respectively. The nitrite accumulation rate (NO^-₂-N/NO^-_x-N) was over 95%.The quantitative results from fluorescence in situ hybridization (FISH) analysis for molecular biology show that the dominant micro-organism was still AOB, about 17.8% of total bacteria，while NOB only 0.6%. The main factors for stable performance of nitrification were FA inhibition and real-time control.

摘要：

为探究短程硝化污泥快速颗粒化的最佳条件，采用SBR反应器，在温度28℃，曝气量0. 2 m³·h^-1，溶解氧(DO)>2.0 mg·L^-1，污泥龄(SRT)为15d的运行工况下，缩短沉降时间为2min，通过以pH作为氨氧化过程的控制参数，优化曝气时间，防止过曝气，经过80周期(19d)成功实现短程硝化絮状污泥的颗粒化，并维持稳定。形成的颗粒污泥粒径在1.5