兼氧—好氧生物流化床氨氮去除及含DMF废水处理效果研究

发布时间：2018-01-15 22:23

本文关键词：兼氧—好氧生物流化床氨氮去除及含DMF废水处理效果研究　出处：《浙江工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：生物流化床作为一种新型的生物膜法技术,具有占地少,传质效果好,剩余污泥少等优点,已经成为国内外水处理技术和工艺研究的热点。在水体污染中,氨氮是造成水体富营养化的关键,也是水体中主要耗氧污染物,对鱼类和某些水生生物有毒害,因此开发高效、节能的污水脱氮工艺具有重大的现实意义。二甲基甲酰胺(DMF)是一种在合成革制造和化工生产中广泛应用的有机溶剂,美国将DMF归类为人体可能致癌物质,目前中低浓度的DMF以降解去除为主,效果不够理想,同时降解过程产生氨氮等无机氮。本文利用流化床工艺对氨氮去除效果和DMF废水处理效果进行研究,为进一步学术研究和工程应用提供参考。实验所用反应器为兼氧-好氧生物流化床,所用载体为粒径0.6~1.2 mm的焦末颗粒。以较低的碳氮比(C/N=0.3)启动实验发现,进水氨氮浓度130 mg/L,经过23天的启动后,出水氨氮值降低至31mg/L,去除率约75%,同时出现较多的钟虫、累枝虫等原生动物。并通过观察启动前期悬浮相悬浮固体浓度(MLSS)和挥发性悬浮固体浓度(MLVSS)的变化发现流化床反应器内微生物主要以附着生长微生物为主,悬浮相微生物数量较少,出水较澄清,悬浮相微生物对废水净化效果不大。较长的水力停留时间有利于反应器对氨氮的去除,在兼氧区的反应中尤其明显,当碳氮比C/N=1时,此时氨氮的去除效果达到最佳,而化学需氧量(COD)的去除效果随着碳氮比的增大而提高,硝态氮的浓度随着COD的增加而减少。当进水氨氮浓度低于141 mg/L时,反应器对氨氮的去除效果能显著提升。反应器对进水DMF浓度为100mg/L的含DMF废水去除效果较好,出水COD值较低,在兼氧区COD和DMF就能达到较好的去除效果。但是,在进水含DMF的条件下,反应器氨氮去除效果明显变差,与不含DMF的废水进行对照实验后,推测DMF对硝化细菌的活性存在一定的抑制。在不投加额外碳源和氮源的条件下,兼氧-好氧流化床装置对于低浓度DMF(100 mg/L)废水也能取得较好的净化效果。
[Abstract]:As a new biofilm technology, biological fluidized bed has the advantages of less occupation, better mass transfer effect, less excess sludge and so on. It has become a hot spot in water treatment technology and technology research at home and abroad. Ammonia nitrogen is the key to eutrophication and the main oxygen-consuming pollutant in water body, which is toxic to fish and some aquatic organisms, so it is highly effective. Energy saving wastewater denitrification process is of great practical significance. Dimethylformamide (DMF) is a widely used organic solvent in synthetic leather manufacturing and chemical production. In the United States, DMF is classified as a possible carcinogen in human body. At present, DMF in medium and low concentrations is mainly degraded and removed, and the effect is not satisfactory. At the same time, ammonia nitrogen and other inorganic nitrogen were produced in the degradation process. In this paper, the removal efficiency of ammonia nitrogen and the treatment efficiency of DMF wastewater were studied by fluidized bed process. The reactor used in the experiment is a facultative aerobic biological fluidized bed. The carrier was coke particles with a diameter of 0.6 ~ 1.2mm. The starting experiment showed that the influent ammonia nitrogen concentration was 130 mg/L with low C / N ratio of C / N ~ (0.3). After 23 days of start-up, the ammonia nitrogen value of the effluent decreased to 31 mg / L, the removal rate was about 75%, and there were more bell worms at the same time. The suspended solid concentration (MLSS) and volatile suspended solid concentration (MLVSSs) of suspension phase in the early stage of initiation were observed. It was found that the main microorganism in fluidized bed reactor was attached growth microorganism. The quantity of suspended microorganism is less, the effluent is more clear, and the suspended microorganism has little effect on the purification of wastewater. The longer HRT is beneficial to the removal of ammonia nitrogen in the reactor, especially in the reaction in the zone of facultative oxygen. When C / N ratio C / N = 1:00, the removal efficiency of ammonia nitrogen reached the best, while the removal efficiency of COD increased with the increase of C / N ratio. The nitrate concentration decreased with the increase of COD, when the influent ammonia concentration was lower than 141 mg/L. The removal efficiency of ammonia nitrogen in the reactor can be improved significantly. The removal efficiency of DMF containing wastewater containing 100 mg / L of influent DMF is better, and the COD value of effluent is lower. The removal efficiency of COD and DMF in the aerobic zone was better than that of the wastewater without DMF. However, under the condition of influent containing DMF, the removal efficiency of ammonia nitrogen in the reactor became worse obviously, which was compared with the wastewater without DMF. It is inferred that DMF can inhibit the activity of nitrifying bacteria to a certain extent, without the addition of additional carbon and nitrogen sources. A facultative aerobic fluidized bed can also be used to purify low concentration DMF(100 mg / L wastewater.
【学位授予单位】：浙江工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703

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