【作者】 王艳捷；

【导师】 邱忠平；

【作者基本信息】 西南交通大学 ， 生物化学与分子生物学， 2008， 硕士

【摘要】 垃圾渗滤液是垃圾卫生填埋过程中产生的难处理的高浓度有机废水,包含多种病原微生物以及某些致癌和促癌物质,对环境的危害很大。厌氧生物处理技术具有能耗少、操作简便、投资及运行费用低等突出特点,且兼有生产气体燃料的功能,是高浓度有机废水处理中最常用、最经济的一种方法。但由于垃圾渗滤液水质十分复杂,含多种有机污染物及重金属离子、氨氮含量高,对微生物有抑制作用,常给厌氧生物工艺运行带来很大的冲击。因此,研究垃圾渗滤液对厌氧微生物的毒性作用,完善垃圾渗滤液的厌氧处理技术,对于垃圾渗滤液的处理与处置具有重要意义。本论文通过厌氧毒性试验（ATA）来研究垃圾渗滤液中氨氮、有机污染物和重金属盐对厌氧微生物的毒性作用,并选用上流式厌氧污泥床（UASB）作为厌氧处理工艺进行实验室模拟试验,考察垃圾渗滤液毒性对厌氧处理工艺运行的影响。研究结果表明:（1）通过气相色谱-质谱联用仪（GC-MS）和原子吸收分光光度计法分别测定“老龄”垃圾渗滤液中有机污染物和重金属,检测出可信度大于60%的有机污染物44种,重金属中砷、铅、铬和镍的含量在0.1mg/L以上。（2）通过ATA试验对“老龄化”特征的渗滤液中重金属、有机污染物和氨氮进行考查。“老龄”渗滤液使污泥相对活性下降55.5%,最大活性区间滞后14d;氨氮、重金属和有机物使厌氧污泥产甲烷活性分别下降36.7%、14.4%和18.1%,最大活性区间分别滞后5d、0d和8d。比较三者的厌氧毒性,受试“老龄”垃圾渗滤液中氨氮对厌氧污泥的毒性影响较大,有机污染物则使厌氧生物体较长的时间才能适应,重金属在浓度较高时,受到抑制的厌氧污泥活性难以恢复。通过线性回归得到氨氮、重金属和有机物的半致死剂量IC₅₀分别为2300mg/L、2.9倍试验用渗滤液的重金属含量和3.2倍试验用渗滤液的有机污染物含量。（3）UASB反应器的实验室模拟试验比较了碱性石灰沉淀、曝气吹脱、以及不同COD浓度在沉淀和吹脱后作为进水的情况,结果表明垃圾渗滤液经石灰沉淀和氨氮吹脱预处理对厌氧处理效果的改善尤为明显,COD去除率达60%,当进水负荷达5kgCOD/m³·d时COD去除率也达50%。就整体而言,UASB运行试验中经长期驯化培养的污泥对毒性物质的适应能力要强于ATA静态试验。（4）垃圾渗滤液在自然存放过程中发生较大程度的自然降解,处理填埋场滞留时间较短的新鲜渗滤液,有毒物质对厌氧微生物的抑制作用表现得较为突出。随着垃圾渗滤液趋于稳定,其COD下降明显,对厌氧微生物的抑制也相应降低,渗滤液呈现“老龄化”特征。但“老龄化”渗滤液的难降解有机物水解成为这类渗滤液生物处理的难点。更多还原

【Abstract】 Municipal landfill leachate, come from the municipal solid wastes(MSW) treatment, contained kinds of pathogeny microorganism and certain substance causing cancer, which is very harmful for the environment.Anaerobic Processing is a sort of low cost and common technology which treats the disposal of wastewater with high concentration. Anaerobic Processing possesses of low energy consumption, convenient operation, low invest and running cost, and accompanied organic degradation with produce gaseous fuel. As a result it is developed broadly and applied. Landfill leachate is a kind of complex organic wastewater with high concentration, and is difficulty treated, which has a inhibition on anaerobic microorganism and creates a hazard in anaerobic processing. So studying and improving the treatment technology of domestic landfill leachate is a important task in the water treatment field today.In this thesis, anaerobic toxicity of landfill leachate is researched by Anaerobic Toxicity Assay (ATA). And UASB was selected as a major object studied and was experimentized analogly in laboratory. The results as follows:1) Atom absorption spectrophotometer and gas chromatograph-mass spectrometer method(GC-MS) were used to measure the concentration of heavy metals and organic pollutants in the landfill leachate. In this kind of landfill leachate, 44 kinds of organic pollutants been discovered were more than 60% in reliability, and As,Pb,Cr and Ni is above 0.1mg/L in the landfill leachate.2) Heavy metal salt, organic and ammonia nitrogen of the leachate that is typical characters of "aging" leachate were study. The results of the experiment showed that the "aging" leachate made the activity decreased 55.5% and the period of most biogas production time delayed 14d. while fresh leachate made the activity of anaerobic sludge been in restrained state in the days of trial, the half lethal dose of heavy metal salt, organic and ammonia nitrogen to anaerobic microorganism is 2.9 times of the content of heavy metal salt of the "aging" leachate, 3.2 times of the content of organic of the "aging" leachate, and 2.3g/L ammonia nitrogen in concentration.3) Compared non-pretreatment leachate with the leachate deposited and blow-off in the basicity with which to act as feed-water of UASB, we found that pretreatment deposited and blow-off in the basicity was of great advantage to anaerobic processing, which the rate of COD removal reached 60 percent. When the load of the leachate by pretreatment reach 5kgCOD/m3·d, the rate of COD removal maintain 50 percent the above.4) Landfill leachate varied relatively large with natural degradation in the course of deposit. The affect of toxicity of leachate for anaerobic microorganism was an important problem need to take into account for fresh leachate. With natural degradation the COD and the biodegradability reduced obviously, and the leachate presented the character of "aging". But the low biodegradability will turn into the difficulty of anaerobic processing.更多还原