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551.
人工湿地中基质与植物对污染物去除效率的影响   总被引:10,自引:4,他引:6  
针对太湖五里湖富营养化水体,采用中试规模的人工湿地现场实验开展了不同基质、不同植物的污染物去除效果研究。基质采用炉渣和沸石2种,在一个湿地池种植单一植物茭白,另一个湿地池种植鸢尾+菖蒲混合植物,同时构建了无植物的对照组湿地。研究表明:(1)在运行初期,沸石和炉渣2种基质对TN、TP的去除率差异为12.5%和12.6%,吸附饱和后,2种基质对TN和TP的去除率差异缩小为3.2%和6.1%,从长期运行来看,炉渣和沸石2种基质在人工湿地中的去除效率差异将减小;(2)茭白单一植物湿地对污染物的去除率与鸢尾+菖蒲混合植物湿地对污染物的去除率两者之间差异不大;(3)人工湿地种植植物后对TN、TP的去除率比无植物状态时分别高出13.6%和19.5%,植物在人工湿地中对污染物的去除发挥了重要作用;(4)在本试验条件下,茭白吸收所去除的氮数量为湿地氮总去除量的8.95%,茭白吸收去除磷的数量为湿地磷总去除量的20.16%,在人工湿地中,茭白吸收对磷的去除效率比对氮的去除效率高。  相似文献   
552.
环境监测中确定最佳点位的关键技术   总被引:2,自引:0,他引:2  
环境监测网络设计的关键问题是确定最佳的环境监测点位 ,而最优的监测点位必须既能代表所在区域环境质量的平均水平 ,又能反映该区域环境质量的变化状况。为此提出一个兼容样本贴近与相似程度的统计量——近似度 ,不仅在理论上证明了其合理性 ,而且在厦门的应用中得到满意的结果 ,从而解决了如何确定环境监测中最佳点位的问题  相似文献   
553.
Comprehensive and joint applications of GIS and chemometric approach were applied in identification and spatial patterns of coastal water pollution sources with a large data set (5 years (2000-2004), 17 parameters) obtained through coastal water monitoring of Southern Water Control Zone in Hong Kong. According to cluster analysis the pollution degree was significantly different between September-next May (the 1st period) and June-August (the 2nd period). Based on these results, four potential pollution sources, such as organic/eutrophication pollution, natural pollution, mineral/anthropic pollution and fecal pollution were identified by factor analysis/principal component analysis. Then the factor scores of each monitoring site were analyzed using inverse distance weighting method, and the results indicated degree of the influence by various potential pollution sources differed among the monitoring sites. This study indicated that hybrid approach was useful and effective for identification of coastal water pollution source and spatial patterns.  相似文献   
554.
A gas–solid fluidized bed bioreactor was successfully used to treat air contaminated with a volatile organic compound (VOC). A bioreactor containing both a fluidized and packed bed of moist peat granules removed ethanol, a representative VOC, from an air stream. The fluidized bed operation mode of the bioreactor outperformed the packed bed mode. The maximum elimination capacity (EC) of ethanol in the fluidized mode was 1520 g m−3 h−1, with removal efficiencies ranging between 45 and 100%, at loadings up to 3400 g m−3 h−1. Maximum EC was 530 g m−3 h−1 in the packed bed mode. Removal efficiency in the fluidized bioreactor was best at the lowest velocity, where the bubbling bed fluidization regime predominated. As gas velocity increased, the size and amount of large bubbles (slugs) increased and removal efficiency decreased while elimination capacity increased.  相似文献   
555.
2 200 m3高炉INBA渣处理系统由于工艺流程设计存在一些不合理,系统在运行过程中带泡沫渣的粒化水经溢流口大量外排,造成大量水资源浪费的同时也对附近的河道造成了污染.通过一系列的改造,解决了上述问题.  相似文献   
556.
采用碱性氧化焙烧工艺回收含铬污泥中的铬,以浸出渣作为焙烧填料,最佳工艺条件为:含铬污泥加入量10g,浸出渣加入量8g,焙烧温度700℃,焙烧时间40min,n(Cr2O3):n(NaNO3):n(Na2CO3):n(NaOH)=1:2:3.5:10。在此条件下,碱性氧化焙烧工艺铬浸出率高达98%以上。  相似文献   
557.
Wastewater produced from a metal plating is a major environmental problem. Industrial auditing revealed that the main source of pollution mainly originated from rinsing water. The characterization of final effluent showed that it is highly contaminated with hazardous heavy metals and cyanide. The concentration of copper, hexavalent chromium, nickel, and cyanide in the rinsing water of metal plating department was 14.8, 40.9, 13.3, and 19 mg/l, respectively. The concentration of cyanide and zinc from the galvanizing department reached 60 and 80 mg/l. The remediation scheme included the application of in-plant control measures via changing the rinsing process followed by the destruction of cyanide and reduction of hexavalent chromium bearing wastes. The pretreated wastes were then mixed with other industrial wastes prior to a combined chemical coagulation-sedimentation using lime and/or lime in combination with ferric chloride. The results indicated that, after applying the waste minimization measures alone at the source, prior to final treatment of industrial waste, removal rates of cyanide, copper, nickel, and chromium concentrations were 23.2%, 14.9%, 32.3%, and 55.3%, respectively in the rinse water from metal plating department. Furthermore, the removal rates of cyanide and zinc in the galvanizing department reached 59.7% and 24.3. The integrated control measures and treatment scheme led to more than 99% removal of copper, nickel, chromium, and zinc, while the complete removal of cyanide was achieved in the final effluent.  相似文献   
558.
Habitat valuation methods were implemented to support remedial decisions for aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy (DOE) Oak Ridge Reservation in Oak Ridge, TN, USA. The habitat valuation was undertaken for six contaminated sites: Contractor's Spoil Area, K-901-N Disposal Area, K-770 Scrapyard, K-1007-P1 pond, K-901 pond, and the Mitchell Branch stream. Four of these sites are within the industrial use area of ETTP and two are in the Black Oak Ridge Conservation Easement. These sites represent terrestrial and aquatic habitat for vertebrates, terrestrial habitat for plants, and aquatic habitat for benthic invertebrates. Current and potential future, no-action (no remediation) scenarios were evaluated primarily using existing information. Valuation metrics and scoring criteria were developed in a companion paper, this volume. The habitat valuation consists of extensive narratives, as well as scores for aspects of site use value, site rarity, and use value added from spatial context. Metrics for habitat value were expressed with respect to different spatial scales, depending on data availability. There was significant variation in habitat value among the six sites, among measures for different taxa at a single site, between measures of use and rarity at a single site, and among measures for particular taxa at a single site with respect to different spatial scales. Most sites had aspects of low, medium, and high habitat value. Few high scores for current use value were given. These include: wetland plant communities at all aquatic sites, Lepomid sunfish and waterbirds at 1007-P1 pond, and Lepomid sunfish and amphibians at K-901 pond. Aquatic sites create a high-value ecological corridor for waterbirds, and the Contractor's Spoil Area and possibly the K-901-N Disposal Site have areas that are part of a strong terrestrial ecological corridor. The only example of recent observations of rare species at these sites is the gray bat observed at the K-1007-P1 pond. Some aspects of habitat value are expected to improve under no-action scenarios at a few of the sites. Methods are applicable to other contaminated sites where sufficient ecological data are available for the site and region.  相似文献   
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