微生物强化猪场沼液脱氮工艺研究

发布时间：2018-03-25 01:38

  本文选题：猪场沼液　切入点：微生物强化　出处：《华中农业大学》2015年硕士论文

【摘要】：猪场沼液是猪场废水经过厌氧发酵后产生的具有高氨氮(NH4~(+)-N)和高化学需氧量(COD)的有机养殖废水。由于沼液的低COD/N特性,微生物再利用困难,氮磷排放不达标成为技术难题。本课题在实验室模拟条件下对猪场沼液除氨菌株、工艺条件以及生物强化序批式生物反应器(SBR)工艺脱氮效果进行了研究,主要结果如下:(1)筛选得到氨氧化细菌AT7(AOB,Nitrosomonas europaea),在起始NH4~(+)-N浓度为200 mg/L-250 mg/L的沼液中处理3 d后,NH4~(+)-N去除率达71.1%;筛选得到亚硝酸氧化细菌Y3-2(NOB,Nitrobacter winogradskyi),4 d后亚硝酸盐(NO2~(-)-N)的积累量降低41.7%。(2)同时接种AT7和Y3-2,浓度分别为105 CFU/m L,转速为200 r/min,吸附剂稻草粉的添加量为0.3 g/100 m L,对于NH4~(+)-N浓度为200 mg/L-250 mg/L的沼液,3 d后NH4~(+)-N去除率达77.8%;对于低NH4~(+)-N为60 mg/L以下的沼液,需添加甲醇为碳源,补加频率为2 d一次,3 d后NH4~(+)-N去除率为80.4%。(3)在SBR系统中,采用曝气和静止交替进行,作用时间分别为6 h和2 h,接种AT7、Y3-2各105 CFU/m L,3 d后NH4~(+)-N去除率为89.3%,转化而成的硝酸盐(NO3~(-)-N)升高39.7%。(4)调节COD/N的最适比例为11:1;以甲醇为碳源,接种硝化细菌和反硝化细菌,NH4~(+)-N、TN、COD和TP的去除率分别为98.7±0.4%,83.7±0.8%,97.4±0.2%,70.6±5.0%。低聚果糖废液能替代甲醇,降低成本,NH4~(+)-N、TN、COD和TP的去除率分别为98.9±0.3%,95.1±1.5%,97.1±0.3%,73.9±3.9%。(5)对NH4~(+)-N浓度为771 mg/L的高浓度沼液,以系统出水循环利用稀释进水的模式,降低NH4~(+)-N浓度至200 mg/L-250 mg/L,SBR系统运行21 d后稳定,NH4~(+)-N、TN、COD和TP去除率分别为98.2±0.2%,77.8±0.5%,94.1±0.6%,77.1±1.6%。(6)室外模拟试验中,日平均温度在9℃-20℃之间,NH4~(+)-N、TN、COD和TP去除率分别可达97.9±0.2%,73.8±0.9%,92.1±0.9%,80.4±1.9%。说明在一定的温度范围内,温度变化对SBR系统的运行没有太大的影响。
[Abstract]:Pig farm biogas liquor is an organic culture wastewater with high ammonia nitrogen (NH4N) and high chemical oxygen demand (COD) produced by anaerobic fermentation of pig wastewater. Because of the low COD/N characteristics of the biogas, it is difficult for microorganism to reuse. It has become a technical problem that the nitrogen and phosphorus discharge is not up to standard. In this paper, the denitrification effect of bioreactor SBR and the strain of ammonia removal from biogas liquid of pig farm were studied under the condition of laboratory simulation. The main results were as follows: 1) the ammonia oxidizing bacteria AT7 AOBN Nitrosomonas europaeaan was screened. After 3 days of treatment in the biogas containing 200 mg/L-250 mg/L concentration of nitrite N, the removal rate of nitrite was 71.1; the nitrite oxidizing bacteria Y3-2NOBNitrobacter winogradskyianine 4 days later, the accumulation of nitrite nitrite no _ 2no _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2O _ 2-N was decreased after screening. AT7 and Y3-2 were inoculated at the same time with a concentration of 105 CFU/m / L, a rotational speed of 200rr / min, an amount of 0.3 g / 100 mL of adsorbent straw powder, and a removal rate of 77.8% for NH _ 4N (N = 200 mg/L-250 mg/L) for 3 days after inoculation; for biogas with low NH _ 4N concentration of less than 60 mg/L, When methanol was added as carbon source, NH _ 4N was added at a frequency of 2 days once a time for 3 days, and NH _ 4N removal efficiency was 80.4. N ~ (3). In SBR system, aeration and rest were used alternately. The optimum ratio of NH _ 4N (removal rate of nitrate-N is 89.3g) to nitrate-nitrate-no _ 3 (-N) increased 39.7g / L ~ (-1) after inoculation with AT7N _ 3-2 105 CFU/m / L ~ (-1) for 6 h and 2 h, respectively, and methanol was used as carbon source. Inoculated with nitrifying bacteria and denitrifying bacteria, the removal rates of COD and TP were 98.7 卤0.410 卤83.7 卤0.810 卤97.4 卤0.2 and 70.6 卤5.0 respectively. Fructose oligosaccharide waste liquid could replace methanol and reduce the cost of NH _ 4 (removal rates of -NTNCOD and TP were 98.9 卤0.35.1 卤95.1 卤1.35 卤3.93.90 卤3.9. 5, respectively). In the outdoor simulation experiment, the NH _ 4N concentration up to 200 mg/L-250 mg 路L ~ (-1) SBR system was reduced by diluting the influent by the system, and the NH _ 4 ~ + _ 4 (COD and TP removal rates were 98.2 卤0.22 ~ 77.8 卤0.5 ~ 94.1 卤77.1 卤1.6.1 卤1.6.6m ~ (-1) respectively) in the outdoor simulation experiment, and the NH _ 4N concentration was reduced to 200 mg/L-250 路L ~ (-1) / L ~ (-1) SBR system for 21 days. The average daily temperature is between 9 鈩，

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