酒精废水消化液生物硝化和脱氮试验

酒精糟液厌氧消化液CODCr浓度为3500～4300mgL,BOD5浓度为1500～2100mgL,TN浓度为400～700mgL,NH3N浓度为300～600mgL。采用SBR反应器对该消化液进行生物脱氮试验,对反应器的有机负荷、氨氮负荷、脱氮效果、脱氮过程中氮形态的变化以及碳源提供等进行了研究分析。试验结果表明,当消化液碳源充足,SBR充水比λ=0.35,缺氧时间3h以及BOD5污泥负荷0.26～0.32kgkg·d条件下,SBR处理出水CODCr598～632mgL,BOD560～100mgL,氨氮6～9mgL,总氮200～216mgL,总氮去除率为60%左右。该处理系统中缺氧段反应时间仅为3h,却承担70%～75%的CODCr总去除负荷,显著提高了该系统的有机负荷和氨氮负荷。在消化液碳源不足的条件下,可投加乙酸钠作为生物脱氮的外碳源,投加量宜为500mgL。

EXPERIMENT ON BIOLOGICAL NITRIFICATION AND DENITRIFICATION OF DIGESTION LIQUID OF ALCOHOL WASTEWATER

The digester liquid of alcohol wastewater was identified at COD_ Cr, BOD_5, TN and NH_3-N concentrations of 3 500～ 4 300 mg/L , 1 500～ 2 100 mg/L, 400～700 mg/L and 300～600 mg/L respectively.The objective of this experiment was to investigate the nitrification and denitrification by SBR with specific emphasis on the main operational parameters.The results demonstrated that when the anoxic time was 3 h, the sludge loading 0.26～0.32 kg BOD_5/kg MLSS·d and carbon source enough, the effluent concentrations were 598～632 mg COD_ Cr/L, 60～ 100 mg BOD_5/L, 6～9 mg NH_3-N/L, and 200～216 mg TN/L with about 60% removal efficiency respectively.In spite of the short anoxic time, the system removed by 70%～75% of total COD_ Cr, which improved the organic and ammonia nitrogen loading exceptionally.Sodium acetate can be taken as the external carbon source of biological denitrification with an appropriate dosage of 500 mg/L COD_ Cr under scarce carbon source condition.