不同外碳源对污泥反硝化特性的影响

Sludge Denitrification Characteristics with Different External Carbon Source

为了选择最优的反硝化外投碳源,应用SBR和A/O反应器,系统地研究了甲醇、乙醇和乙酸钠作为外碳源时污泥的反硝化特性.甲醇、乙醇和乙酸钠作为外碳源时污泥的比反硝化速率分别为3.2 mg/g·h^(-1)、9.6 mg/g·h^(-1)和12 mg/g·h^(-1).甲醇和乙醇作为外碳源时污泥产率大致相同(约为0.40 g/g),而乙酸钠作为外碳源其污泥产率最高(0.65 g/g),甲醇作为外碳源时系统启动时间和驯化期长,不能迅速地响应进水水质的变化.乙醇是反硝化处理系统的最优外加碳源,具有反硝化速率高、污泥产率低、响应迅速、来源广且对环境的影响小等优点.

In order to select the best external carbon source for denitrification, the denitrification characteristics of the commonly used external carbon sources, methanol, ethanol and acetate have been studied using the SBR reactor and A/O nitrogen removal process. Results showed that the different external carbon sources had significantly influenced denitrification activity and process. It had Been found that the specific denitrification rates of methanol, ethanol and acetate were reached up to 3.2 mg/g· h^-1, 9.6 mg/g·h^-1 and 12 mg/g·h^-1, respectively. The sludge yield of methanol and ethanol was similar （about 0.4 g/g）, while the sludge yield of acetate was very high （0.65 g/g）. In addition, nitrogen removal was enhanced immediately after ethanol and acetate addition. However, methanol as carbon sources didn＇t response immediately and had a long adaptation time. By comparison, ethanol was the best external carbon source, for its high denitrification rate, low sludge yield, quick response, easily obtained and low influence on environment.