高盐高氮榨菜废水生物脱氮试验研究

Study on biological nitrogen removal in mustard tuber wastewater with high salinity and high nitrogen concentration

针对榨菜生产过程中产生的高盐高氮废水,探讨了在高盐条件下有机负荷、氮负荷、DO、pH等因素对SBBR反应器脱氮效能的影响.研究结果表明,在SBBR反应器中接种从榨菜腌制废水中筛选出的耐盐菌后,可使反应器对高盐废水具有良好的适应性,同时镜检发现其生物膜中存在大量丝状菌;反应器具有较强的同时硝化反硝化能力,有机负荷、氮负荷、DO、pH等因素对反应器脱氮效能的影响显著;研究得出其最优运行参数为有机负荷小于1·0kg·m^(-3)·d^(-1)、氮负荷小于0·15kg·m^(-3)·d^(-1)、DO大于5mg·L^(-1)、进水pH大于7及温度大于20℃,在此条件下可使进水盐度(以NaCl计)为2%、CODCr为3500mg·L^(-1),TN为530mg·L^(-1),NH_4^+-N为150mg·L^(-1)的榨菜废水,其出水CODCr小于80mg·L^(-1)、NH_4^+-N小于3mg·L^(-1)、TN小于16mg·L^(-1),NH_4^+-N和TN的去除率分别为98%和96%。

Aiming at the high salinity and high nitrogen of the wastewater produced in the manufacturing process of mustard tuber, the influence of the factors such as organic loading rate （ OLR）, nitrogen loading rate （NLR）, DO and pH on the effect of the nitrogen removal of SBBR reactor in the condition of high salinity was studied. The results showed that if the halophilic bacteria selected from mustard tuber wastewater were inoculated in the SBBR reactor, the reactor could get a better adaptability to the high salinity. And by the observation of microscope, it was found that there were a great many of filamentous organisms proliferating on the biological film. The reactors had relatively strong simultaneous nitrification and denitrification capacity, the influences of OLR, NLR, DO and pH on the nitrogen removal were significant. And the operating conditions were OLR≤ 1.0 kg·m^-3 ·d^-1 , NLR≤0.15 kg·m^-3 ·d^-1 , DO≥5 mg·L^-1 , pH≥7, T≥20℃. Under this condition, if the influent salinity of the wastewater（ as NaCl） was 2%, COD = 3500 mg· L^- 1 , TN = 530 mg· L^-1 , NH4^＋ -N = 150 mg· L^-1, and the effluent quality will be COD 〈 80 mg· L^- 1 ,TN 〈 16 mg· L^-1 , NH^4＋ -N 〈 3 mg· L^-1. NH4^＋ -N and TN removals rates were 98% and 96% respectively.