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221.
分体式膜-生物反应器在废水处理中的工艺条件   总被引:11,自引:3,他引:11  
对分体式膜-生物反应器(RMBR)处理废水进行了研究.进水CODCr:312~584mg/L,RMBR的出水CODCr在运行4d后<15 mg/L并稳定.向生物反应器添加0.5g/L(混合液)的粉末活性炭(PAC)后出水CODCr<4.22mg/L.膜侧污水流速在0.9~1.9m/s范围内,临界膜通量随膜侧污水流速的增大而增大.添加PAC,组合添加PAC和Al2(SO4)3·18 H2O均可有效提高临界膜通量.在膜侧流速1.9m/s的条件下,临界膜通量从72L/(m2·h)分别增至76L/(m2·h)和81 L/(m2·h)在22℃~30℃范围内,每升高1℃可提高膜通量1.9%.在连续运行100d中,RMBR可在无任何物理,化学清洗的条件下运行14d而透膜压力无增大,膜通量不降低.对于已污染的膜,水清洗、水碱共间清洗、水碱酸共同清洗可分别恢复至新膜膜通量的47%、83%、94%.  相似文献   
222.
文中利用市及旗县区监测站近几年监测数据对西辽河上游的污染程序进行了讨论 ,并进行了趋势分析 ,提出污染防治对策 ,旨在为辽河治理提供参考  相似文献   
223.
上海地铁车站恶臭气体污染调查   总被引:2,自引:0,他引:2  
对地铁一号线人民广场站和漕宝路站的臭污染情况进行了调查,采用嗅沉测试和公众调查方法对恶臭进行测试和分析。结果表明,人民广场站的IAQ以3级(明显)为主、漕宝路站以2级(轻微)为主,污染程度与人流量和通风状况相关,漕宝路站的空气质量明显好于人民广场站。  相似文献   
224.
为了解不同形式坡道式 车库中汽车尾气污染状况,对4座典型的坡道式停车库进行了空气质量监测,并同时进行车流量统计、计算和分析了信车库内污染物浓度与车流量之间的相关性,监测结果表明,停车库NOx和CO浓度符合相应标准,而地下停车库排气Ox有超桔现象。结论是地面停车主轵成于地下停车库,地下停车库的送排风系统必须合理设置。  相似文献   
225.
区域环评中废水排放量的预测方法研究   总被引:1,自引:0,他引:1  
阐述了区域环评污染物排放源强的预测原则,对区域开发活动中废水量和COD排放量的预测方法作了详细论述,并以温州滨海新区环评为例作了实证研究.  相似文献   
226.
Persulfate can efficiently decolorize azo dyes through oxidizing these compounds, which enabled us to develop a method of rapid spectrophotometric determination of persulfate for monitoring the wastewater treatment on the basis of the oxidation decolorization of azo dyes. Four azo dyes with different molecular structures were investigated as probes, and the influences of operation parameters including reaction time, solution pH, initial dye concentration, and initial concentration of activator Fe(2+) were checked on the determination of persulfate. Under optimum conditions, the decolorization degree of the dyes responded linearly with persulfate concentration for all the four azo dyes, and the linear range and detection limit were found to be 2.0-150 μmol L(-1) and 0.62 μmol L(-1) for rhodamine B, 2.0-100 μmol L(-1) and 0.42 μmol L(-1) for methylene blue, 4.0-150 μmol L(-1) and 0.50 μmol L(-1) for methyl violet, and 20-150 μmol L(-1) and 8.1 μmol L(-1) for orange II. A persulfate treatment of a spiked wastewater sample was satisfactorily monitored with the new method.  相似文献   
227.
Eight heavy metals (Cu, Zn, Fe, Mn, Cd, Cr, Ni, and Pb) in 14 different wild-growing edible mushroom species (Coprinus comatus, Voluariella volvacea, Pleurotus nebrodensis, Hypsizigus marmoreus, Hericium erinaceus, Agrocybe aegerita, Lenfinus edodes, Collybia velutipes, Agaricus bisporus, Russula albida, Clitocybe conglobata, Pleurotus eryngii, Lepista sordida, and Pleurotus ostreatus) collected from Yunnan province, China, were determined by inductively coupled plasma-atomic emission spectrometry after microwave digestion. All element concentrations were determined on a dry weight basis. The ranges of element concentrations for copper, zinc, iron, manganese, cadmium, chromium, nickel, and lead were 6.8-31.9, 42.9-94.3, 67.5-843, 13.5-113, 0.06-0.58, 10.7-42.7, 0.76-5.1, and 0.67-12.9 mg/kg, respectively. In general, iron content was higher than other metals in all mushroom species. The levels of zinc, cadmium, and lead in some edible mushroom samples were found to be higher than legal limits. The relative standard deviations were found below 10%. The accuracy of procedure was confirmed by certified reference material.  相似文献   
228.
Previously it has been suggested that certain organic aerosol components of wood smoke have enhanced ultraviolet absorption at 370 nm relative to 880 nm in two-wavelength aethalometer measurements. This enhanced absorption could serve as an indicator of wood burning particles. Two-wavelength (370 nm and 880 nm) aethalometer measurements were made at urban sites in Rochester, New York and Laredo, Texas from August 1 to December 31, 2009 and from December 23, 2007 to January 2, 2008, respectively. In Rochester, Delta-C (UVBC(370 nm)- BC(880 nm)) values were higher by a factor of 3 during the night than during the day in November and December when residential wood burning was common. In Laredo, particularly high Delta-C values were observed on Christmas Eve and New Year's Eve and were attributed to biomass burning and firework emissions. Exponential decay was found to be a good estimator for predicting BC concentrations at different wind speeds regardless of wind directions.  相似文献   
229.
River water quality and pollution sources in the Pearl River Delta, China   总被引:1,自引:0,他引:1  
Some physicochemical parameters were determined for thirty field water samples collected from different water channels in the Pearl River Delta Economic Zone river system. The analytical results were compared with the environmental quality standards for surface water. Using the SPSS software, statistical analyses were performed to determine the main pollutants of the river water. The main purpose of the present research is to investigate the river water quality and to determine the main pollutants and pollution sources. Furthermore, the research provides some approaches for protecting and improving river water quality. The results indicate that the predominant pollutants are ammonium, phosphorus, and organic compounds. The wastewater discharged from households in urban and rural areas, industrial facilities, and non-point sources from agricultural areas are the main sources of pollution in river water in the Pearl River Delta Economic Zone.  相似文献   
230.
A series of perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have been recently measured in a variety of environmental samples and biological matrices. In order to better understand the human exposure routes of these chemicals, levels of PFOS, PFOA, perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHS) and perfluorooctane sulfonamide (PFOSA) in house dust samples were investigated. The data revealed a correlation between the concentrations of PFCs and the percentage of carpeting in the house; older houses tended to have less carpeting, hence lower levels of these perfluorinated compounds in their dust.  相似文献   
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