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991.
微生物技术改善河道水质的研究   总被引:1,自引:0,他引:1  
该课题是探索直接利用人工培养的微生物改善河道水质的研究。在桂林桃花江河道投放反硝化细菌制剂2个月后,水质有了一定程度的改善,COD和TN的浓度降低,但TP和浊度变化幅度不大。受进水水质和低温天气的影响,反硝化细菌制剂的净化作用及反硝化作用不能充分发挥。  相似文献   
992.
993.
生物反硝化除氮研究   总被引:12,自引:0,他引:12  
  相似文献   
994.
通过水力停留时间对亚硝酸氮积累的影响研究发现,在HRT相对亚硝酸菌的增殖富足的条件下,体系内的碱度是影响亚硝酸氮积累的主要因素。24h连续监测表明,针对“中老龄”垃圾渗滤液这一特定水质,将HRT设在4.5d为宜。  相似文献   
995.
Effect of added carbon source and nitrate concentration on the denitrifying phosphorus removal by DPB sludge was systematically studied using batch experiments, at the same time the variation of ORP was investigated.Results showed that the denitrifying and phosphorus uptake rate in anoxic phase increased with the high initial anaerobic carbon source addition. However once the initial COD concentration reached a certain level, which was in excess to the PHB saturation of poly-P bacteria, residual COD carried over to anoxic phase inhibited the subsequent denitrifying phosphorus uptake. Simultaneously, phosphate uptake continued until all nitrate was removed, following a slow endogenous release of phosphate. High nitrate concentration in anoxic phase increased the initial denitrffying phosphorus rate. Once the nitrate was exhausted, phosphate uptake changed to release. Moreover, the time of this turning point occurred later with the higher nitrate addition. On the other hand, through on-line monitoring the variation of the ORP with different initial COD concentration, it was found ORP could be used as a control parameter for phosphorus release, but it is impossible to utilize ORP for controlling the denitrificaion and anoxic phosphorus uptake operations.  相似文献   
996.
反硝化实验方法研究综述   总被引:3,自引:0,他引:3  
氮磷是富营养化评价和预测的主要指标之一,由氮磷引发的水体快速富营养化和污染是当今全球面临的一个重大环境问题。沉积物是水体生态系统中N的归宿场所之一,反硝化作用是脱氮的重要机制。本文重点介绍了沉积物—水界面上反硝化常用的实验方法(乙炔抑制法,氮气通量法,同位素对法等)以及它们的优点和存在的缺陷,并指出了今后反硝化实验的研究方向。  相似文献   
997.
氧化沟同时硝化反硝化的生物脱氮机理   总被引:12,自引:1,他引:12  
氧化沟是一种得到广泛应用的有机废水生物反应器 ,简要介绍了氧化沟生物废水处理技术的特点和典型工艺 ,并就氧化沟的硝化反硝化脱氮功能和同时硝化反硝化进行了讨论 ,运用电子计量学方法 ,推导并讨论了同时硝化反硝化反应的计量方程式。  相似文献   
998.
同时硝化反硝化的试验研究   总被引:33,自引:0,他引:33  
在培养和富集硝化菌的基础上,通过控制溶解氧浓度(0.5-1mg/L)观察到同时硝化反硝化现象的存在。进水氨氮投加浓度为50mg/L和100mg/L的2个试验组,总氮分别有58.4%和62.6%损失,作者还结合试验结果,对同时硝化反硝化过程的影响因素和可能机理进行了分析。  相似文献   
999.
Anaerobic ammonium oxidation (ANAMMOX) technology has potential technical superiority and economical efficiency for the nitrogen removal from landfill leachate, which contains high-strength ammonium nitrogen (NH4 -N) and refractory organics. To complete the ANAMMOX process, a preceding partial nitritation step to produce the appropriate ratio of nitrite/ammonium is a key stage. The objective of this study was to determine the optimal conditions to acquire constant partial nitritation for landfill leachate treatment, and a bench scale fixed bed bio-film reactor was used in this study to investigate the effects of the running factors on the partial nitritation. The results showed that both the dissolved oxygen (DO) concentration and the ammonium volumetric loading rate (Nv) had effects on the partial nitritation. In the controlling conditions with a temperature of 30±1℃, Nv of 0.2-1.0 kg NH4 -N/(m3d), and DO concentration of 0.8-2.3 mg/L, the steady partial nitritation was achieved as follows: more than 94% partial nitritation efficiency (nitrite as the main product), 60%-74% NH4 -N removal efficiency, and NO2--N/NH4 -N ratio (concentration ratio) of 1.0-1.4 in the effluent. The impact of temperature was related to iVv at certain DO concentration, and the temperature range of 25-30癈 was suitable for treating high strength ammonium leachate. Ammonium-oxidizing bacteria could be acclimated to higher FA (free ammonium) in the range of 122-224 mg/L. According to the denaturing gradient gel electrophoresis analysis result of the bio-film in the reactor, there were 25 kinds of 16S rRNA gene fragments, which indicated that abundant microbial communities existed in the bio-film, although high concentrations of ammonium and FA may inhibit the growth of the nitrite-oxidizing bacteria and other microorganisms in the reactor.  相似文献   
1000.
Using the surface of poly (sulfone) hollow fiber membrane segments as grafted layer, the hydrophilic acrylamide chain was grafted on by UV-photoinduced grafting polymerization. The gained improvement of surface wettability for the modified membrane was tested by measuring the contact-angle as well as FTIR spectra. Then correlation between the hydrophilic ability of support material and the biofilm adherence ability was demonstrated by comparing the pollutant removal rates from urban wastewater via two identical lab-scale up-flow biological aerated filters, one employed the surface wettability modified poly (sulfone) hollow fiber membrane segment as biofilm carder and the other employed unmodified membrane segment as biofilm carder. The experimental results showed that under the conditions of influent flux 5 L/h, hydraulic retention time 9 h and gas to liquid ratio (G/L) 10: 1, the removal rates of chemical oxygen demand (COD) and ammonium nitrogen (NH4^+-N) for the modified packing filter and the unmodified packing filter was averaged at 83.64% and 96.25%, respectively, with the former filter being 5%-20% more than the latter. The effluent concentration of COD, NH4^+-N and turbidity for the modified packing filter was 25.25 mg/L, 2 mg/L and 8 NTU, respectively. Moreover, the ammonium nitrogen removal performance of the filter packing the modified PSF was compared with the other bioreactor packing of an efficient floating medium. The biomass test indicated that the modified membrane matrixes provided better specific adhesion (3310-5653 mg TSS/L support), which gave a mean of 1000 mg TSS/L more than the unmodified membrane did. In addition, the phenomenon of simultaneous denitrification on the inner surface of the support and nitrification on the outer surface was found in this work.  相似文献   
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