不同类型碳源及其投加量对污泥反硝化的影响研究

Effects of Different Types and Dosages of Carbon Sources on Denitrification of Activated Sludge

为了考察不同种类外加碳源及其投加量对反硝化的影响,以间歇式活性污泥法(SBR)工艺污水处理厂曝气阶段活性污泥为研究对象,分别以乙酸钠、乙醇、葡萄糖以及甲醇等碳源,并维持混合液悬浮固体浓度(MLSS)3 500mg/L,pH 7.2～8.0,温度26±0.5℃,并对SBR反应器按照先好氧曝气(1.5h)后投加碳源缺氧搅拌的模式进行反硝化试验研究.结果表明:1)以乙酸钠为碳源时,反硝化速率为13.27mgN/(L.h),比反硝化速率为3.8mgN/gMLSS.h;2)以乙醇为碳源时,反硝化速率较慢,为4.2mgN/(L.h),比反硝化速率为1.2mgN/gMLSS.h;3)以葡萄糖作为碳源时,反应速率更慢,平均反硝化速率约为1mg/(L.h);4)以甲醇作为碳源时,对NO3--N的去除没有明显作用.在实际工程中,需要短期投加碳源,建议采用乙酸钠.

In order to investigate the effects of different types and dosages of carbon sources on denitrification of activated sludge which was taken from the aeration phase of SBR technology sewage treatment plant,four different types of carbon sources, i. e. sodium acetate, ethanol, glucose and methanol were selected respectively at the level of MLSS 3500 mg/L,pH 7.2 - 8. 0,and temperature 26 ± 0. 5℃ with first aerobic aeration （1. 5 hours） plus anoxic agitation mixing with additional carbon sources. The results showed： （1） with sodium acetate as the carbon source,the denitrification rate was 13. 27 mgN / （L · h）; （2）compared with sodium acetate, the reaction was similar with the ethanol as the carbon resource of denitrification,but denitrification rate was 4. 2 mgN/（L · h） ; （3）glucose was more difficult to be used as the carbon resource for denitrifieation with the average denitrifieation rate 1 mgN/（L · h）;（4） when adding methanol as carbon source, there was no obvious effect on denitrifieation. In practical engineering, to meet the need for short-term dosing carbon source, sodium acetate is recommended to be used.