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191.
营养源对活性艳红脱色降解体系的影响研究   总被引:2,自引:1,他引:2  
黄民生  邱立俊 《上海环境科学》2002,21(7):419-422,431
选择活性艳红X-3B为脱色和降解对象,将白腐真菌固定在生化填料上构建白腐真菌生物膜反应器,并以接种活性污泥的生物膜反应器为对照,考察了营养源对活性艳红脱色降解的影响。实验表明,对白腐真菌Shu-13采用查氏培养基预培养和在反应器中投加适量蔗糖及酱油废水,均能明显提高活性艳红X-3B的脱色率。城市污水中的营养源,不足以满足白腐真菌对活性艳红X-3B的脱色降解需要,白腐真菌Shu-13对富氮条件存在依赖性。在富营养条件下,白腐真菌Shu-13生物膜反应器对活性艳红X-3B的脱色效果明显优于活性污泥。营养源及其浓度、菌种是影响pH变化的重要因素,活性污泥和酱油曲霉生物膜反应器的出水pH变化规律,与Shu-13存在明显不同,Shu-13对活性艳红X-3B的脱色过程中发生了明显的降解作用,而这种作用对生物膜恢复其污染物净化功能是至关重要。另外,酱油废水中存在的酱油曲霉属于半知菌纲的白腐真菌,其对活性艳红X-3B也有较显著的脱色降解效果。  相似文献   
192.
阐述了用不完全厌氧——好氧工艺和投入优势菌的方法处理丝绸染整及砂洗废水的原理,工艺流程,工艺参数、经济效益及结果分析。从实验室及生产试验数据看,此法可使废水的COD由2000—3000mg/l降低至100mg/l以下,平均去除率达96%。出水BOD小于30mg/l,平均去除率为95%。  相似文献   
193.
受污染饮用水水源生物预处理技术   总被引:27,自引:1,他引:27  
阐述了以石英砂、陶粒和弹性立体为填料的生物滤池、生物流化床和生物接触氧化等几种常见受污染饮用水水源生物预处理技术的工艺特点,运动参数及处理效果,及国内以淮水为源水的蚌埠自来水厂、以姚江为源水的宁波梅林和和以深圳水库为源水的,3个日处理量分别为1万t、4万t和400万t的生物预处理工程情况,并对生物接触氧化法预处理工艺的填料选择、挂膜、气水比和积泥反冲等技术问题进行了讨论。  相似文献   
194.
Controlling hydrogen sulfide (H2S) odors and emissions using a single, effective treatment across a town-scale sewer network is a challenge faced by many water utilities. Implementation of a sewer diversion provided the opportunity to compare the effectiveness of magnesium hydroxide (Mg(OH)2) and two biological dosing compounds (Bioproducts A and B), with different modes of action (MOA), in a field-test across a large sewer network. Mg(OH)2 increases sewer pH allowing suppression of H2S release into the sewer environment while Bioproduct A acts to disrupt microbial communication through quorum sensing (QS), reducing biofilm integrity. Bioproduct B reduces H2S odors by scouring the sewer of fats, oils and grease (FOGs), which provide adhesion points for the microbial biofilm. Results revealed that only Mg(OH)2 altered the microbial community structure and reduced H2S emissions in a live sewer system, whilst Bioproducts A and B did not reduce H2S emissions or have an observable effect on the composition of the microbial community at the dosed site. Study results recommend in situ testing of dosing treatments before implementation across an operational system.  相似文献   
195.
The spores of Cladosporium Link. are often present in the air in high quantities and produce many allergenic proteins, which may lead to asthma. An aerobiological spore monitoring program can inform patients about the current spore concentration in air and help their physicians determine the spore dose that is harmful for a given individual. This makes it possible to develop optimized responses and propose personalized therapy for a particular sensitive patient. The aim of this study was to assess the extent of the human health hazard posed by the fungal genus Cladosporium. For the first time, we have determined the number of days on which air samples in Poland exceeded the concentrations linked to allergic responses of sensitive patients, according to thresholds established by three different groups(2800/3000/4000 spores per 1 m~3 of the air). The survey was conducted over three consecutive growing seasons(April–September, 2010–2012) in three cities located in different climate zones of Poland(Poznan, Lublin and Rzeszow). The average number of days exceeding 2800 spores per cubic meter(the lowest threshold) ranged from 61(2010) through 76(2011) to 93(2012), though there was significant variation between cities. In each year the highest concentration of spores in the air was detected in either Poznan or Lublin, both located on large plains with intensive agriculture. We have proposed that an effective, science-based software platform to support policy-making on air quality should incorporate biological air pollutant data,such as allergenic fungal spores and pollen grains.  相似文献   
196.
Performance of a full-scale anoxic-oxic activated sludge treatment plant(4.0×10~5 m~3/day for the first-stage project) was followed during a year.The plant performed well for the removal of carbon,nitrogen and phosphorus in the process of treating domestic wastewater within a temperature range of 10.8℃ to 30.5℃.Mass balance calculations indicated that COD utilization mainly occurred in the anoxic phase,accounting for 88.2% of total COD removal.Ammonia nitrogen removal occurred 13.71% in the anoxic zones and 78.77% in the aerobic zones.The contribution of anoxic zones to total nitrogen(TN) removal was 57.41%.Results indicated that nitrogen elimination in the oxic tanks was mainly contributed by simultaneous nitrification and denitrification(SND).The reduction of phosphorus mainly took place in the oxic zones,51.45% of the total removal.Denitrifying phosphorus removal was achieved biologically by 11.29%.Practical experience proved that adaptability to gradually changing temperature of the microbial populations was important to maintain the plant overall stability.Sudden changes in temperature did not cause paralysis of the system just lower removal efficiency,which could be explained by functional redundancy of microorganisms that may compensate the adverse effects of temperature changes to a certain degree.Anoxic-oxic process without internal recycling has great potential to treat low strength wastewater(i.e.,TN 35 mg/L) as well as reducing operation costs.  相似文献   
197.
Nitrous oxide (N2O) is a potent greenhouse gas that can be emitted during biological nitrogen removal. N2O emission was examined in a multiple anoxic and aerobic process at the aeration rates of 600 mL/min sequencing batch reactor (SBRL) and 1200 mL/min (SBRH). The nitrogen removal percentage was 89% in SBRL and 71% in SBRH, respectively. N2O emission mainly occurred during the aerobic phase, and the N2O emission factor was 10.1% in SBRL and 2.3% in SBRH, respectively. In all batch experiments, the N2O emission potential was high in SBRL compared with SBRH. In SBRL, with increasing aeration rates, the N2O emission factor decreased during nitrification, while it increased during denitrification and simultaneous nitrification and denitrification (SND). By contrast, in SBRH the N2O emission factor during nitrification, denitrification and SND was relatively low and changed little with increasing aeration rates. The microbial competition affected the N2O emission during biological nitrogen removal.  相似文献   
198.
以3类常用的碳源(乙酸钠、葡萄糖和甲醇)为研究对象,在3个稳定运行的SBR系统内考察了碳源种类对污水生物脱氮过程中N_2O释放的影响。结果显示,各系统内N_2O的释放主要发生在好氧硝化阶段,且在以乙酸钠为碳源的系统内氨氧化速率最快,TN去除率最大,但同时N_2O的释放速率、累积释放量(4.44 mg)和转化率(1.3%)也最大。而以甲醇为碳源的小试系统脱氮效果较差,TN去除率仅为59.5%,但N_2O的释放速率、累积释放量和转化率均最低。在实际污水处理过程中,当以温室气体N_2O释放作为判断标准时,此研究结果可为碳源的选择提供依据。  相似文献   
199.
基于降低温室效应的航空器运行策略   总被引:2,自引:2,他引:0  
以航空器运行对环境造成温室效应的两个主要因素—CO_2和凝结尾为研究对象,通过绝对全球温变潜势(AGTP)建立科学统一的衡量标准,将CO_2和凝结尾对环境的影响转换为全球地表温度的改变,为降低温室效应提供依据。最后结合典型高空的探空资料对实际增温进行计算,对比分析25、50、100年时间水平下CO_2和凝结尾对全球地表温度造成的影响,为航空器降低温室效应提供飞行高度指导。  相似文献   
200.
Simultaneous anammox and denitrification(SAD) is an efficient approach to treat wastewater having a low C/N ratio; however, few studies have investigated a combination of SAD and partial nitritation(PN). In this study, a lab-scale up-flow blanket filter(UBF) and zeolite sequence batch reactor(ZSBR) were continuously operated to implement SAD and PN advantages, respectively. The UBF achieved a high total nitrogen(TN) removal efficiency of over 70% during the start-up stage(days 1–50), and reached...  相似文献   
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