剩余污泥和餐厨垃圾发酵液作为反硝化碳源可利用性研究

The Availability of Excess Activated Sludge and Food Waste Hydrolysate as Carbon Source for Denitrification

利用剩余污泥和餐厨垃圾发酵液进行反硝化实验,考察其作为外加碳源的可利用性,并验证了发酵液对实际生活污水的脱氮效果。结果表明,相较于产酸总量而言,总挥发性脂肪酸(TVFAs)在发酵液中含量对反硝化效果影响更显著,且TVFAs含量越高,对应的比反硝化速率μ也越高。以pH为7.0、底物的质量浓度120 g/L、有机负荷率8 g/(L·d),污泥停留时间为8 d的实验条件产生的发酵液,TVFAs的质量分数大于85%,以其作为反硝化碳源能够获得较好的反硝化效果,最大比反硝化速率可达14.2 mg/(g·h)。将该发酵液用于生活污水的脱氮处理,当COD/ρ(NO^3^--N)为6时,TN去除率达到85%左右,出水TN的质量浓度低于6 mg/L。

Fermentation liquid of excess activated sludge and food waste was applied as external carbon source to investigated the availability for deniWification, while the effect of ferrnentation liquid on domestic sewage was proved. The results showed that the proportion of TVFAs in the fermentation liquid was more significant on the denitrification performance compared with the acid production. The higher the proportions of TVFAs, the corresponding ratio of denitrifieation rate （μ） was higher： When the experiment condition of anaerobic fermentation was at pH of 7.0, substrate mass concentration of 120 g/L, OLR of 8 g/（L.d） and SRT of 8 d, the mass fraction of TVFAs was up to 85%. A superior performance of denitdfieation was obtained when the fermentation liquid was used as external carbon source, and the maximum specific denitrification rate of μ achived to 14.2 mg/（g· h）. The utilization of fermentation liquid as carbon source for authentic domestic sewage denitrifieation was proved to be at the optimal situation when the COD/p（NO3--N） was at 6. At the optimal situation, the removal rate of TN was about 85%, while the effluent mass concentration was less than 6 mg/L.