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731.
氰化尾渣资源化应用的清洁生产技术研究   总被引:1,自引:0,他引:1       下载免费PDF全文
以鑫汇金矿的氰化尾渣为研究对象,利用工艺矿物学研究方法,分别进行光谱分析、物相分析和化学分析. 氰化尾渣中w(Pb)和w(Zn)较高,分别达到12.45%和14.00%. 方铅矿和闪锌矿为可回收的铅锌矿物,2种矿粒度主要分布于10~43 μm. 针对方铅矿、闪锌矿的浮选特点,对矿浆进行预处理,并利用新型浮选技术和药剂制度,以提高选矿生产技术指标. 其中铅锌混合精矿中w(Pb)和w(Zn)分别为24.41%和24.55%,锌精矿中w(Zn)为46.63%. 在选矿废水中加入氧化剂,可使其净化后循环利用,由此可节约新鲜水380 m3/d;尾矿可作为制酸原料和水泥原料.   相似文献   
732.
用物化法处理卷烟厂综合废水的实践   总被引:5,自引:0,他引:5  
根据卷烟厂废水的特性,采用气浮加过滤,并在调节池辅以射流曝气的处理工艺,对郴州卷烟厂综合废水进行处理。实践证明,污染物的去除率达85%~95%,满足了达标排放的要求。   相似文献   
733.
扬州市区大气环境污染特征分析及其防治对策   总被引:6,自引:1,他引:5  
以扬州市区“八五"期间大气环境监测数据为基础,评价了大气环境质量的现状,分析了大气污染特征及其产生原因,揭示了污染变化规律,指出了市区大气环境存在的主要问题。最后,提出了市区大气污染防治对策。   相似文献   
734.
介绍了水解 接触氧化 气浮工艺在宠物食品加工废水中的应用。实践表明 ,在进水CODCr、BOD5和SS分别为 2 5 0 0mg/L、1 6 0 0mg/L和 2 5 0mg/L的情况下 ,出水的CODCr、BOD5和SS分别为 70mg/L、1 5mg/L和 4 0mg/L ,达到了《污水综合排放标准》(GB8978 96 )一级标准。经过 1年半的运行表明 ,该工艺具有运行稳定性好、处理效率高、操作管理方便的优点。  相似文献   
735.
针对浮选过程中塑料可浮性波动问题,以表面重构和热力学分析为理论基础,研究了亲水改性后的聚对苯二甲酸乙二醇酯(PET)和聚氯乙烯(PVC)塑料的亲疏水性对环境的响应规律.结果表明,PET在空气、乙醇和水中分别恢复82%、47%和0.2%的疏水性,PVC则恢复100%、37%和2%(温度70℃).与低温极性环境相比,高温非...  相似文献   
736.
• PyLUR comprises four modules for developing and applying a LUR model. • It considers both conventional and novel potential predictor variables. • GDAL/OGR libraries are used to do spatial analysis in the modeling and prediction. • Developed on Python platform, PyLUR is rather efficient in data processing. Land use regression (LUR) models have been widely used in air pollution modeling. This regression-based approach estimates the ambient pollutant concentrations at un-sampled points of interest by considering the relationship between ambient concentrations and several predictor variables selected from the surrounding environment. Although conceptually quite simple, its successful implementation requires detailed knowledge of the area, expertise in GIS, statistics, and programming skills, which makes this modeling approach relatively inaccessible to novice users. In this contribution, we present a LUR modeling and pollution-mapping software named PyLUR. It uses GDAL/OGR libraries based on the Python platform and can build a LUR model and generate pollutant concentration maps efficiently. This self-developed software comprises four modules: a potential predictor variable generation module, a regression modeling module, a model validation module, and a prediction and mapping module. The performance of the newly developed PyLUR is compared to an existing LUR modeling software called RLUR (with similar functions implemented on R language platform) in terms of model accuracy, processing efficiency and software stability. The results show that PyLUR out-performs RLUR for modeling in the Bradford and Auckland case studies examined. Furthermore, PyLUR is much more efficient in data processing and it has a capability to handle detailed GIS input data.  相似文献   
737.
郭鼎 《环境与发展》2020,(1):66-66,68
本文从MODIS数据的气溶胶光学厚度反演为理论出发,以河南省近期某一时段下的大气质量为研究对象,论证了反演手段与地面实测数据的契合性和大气遥感监测在大范围时空区域内的优越性和不可替代性;同时结合地面实测数据对河南省AOD空气质量监测做了研究分析,探讨了大气污染专项防治专项的绩效成果并对其影响因素做了进一步分析。在环境问题日益迫切和国民环保意识越发迫切的当下,大气遥感监测势必将会在环保领域发挥更大的作用。  相似文献   
738.
The objective of this study was to determine the concentrations of inorganic ions present in particulate matter smaller than 10 µm (PM10), released into the environment by industrial, domestic and mobile sources in Duzce. To assess spatial variations, samples were collected from two sampling sites that had urban and suburban characteristics. Further, the process was carried out in two seasons to understand the seasonal variations. An ion chromatography device was used for analyzing the inorganic ion content in the collected samples. The highest levels of inorganic ion concentrations were measured at the urban sampling site during the winter campaign. Furthermore, the highest ion concentrations were measured for SO42? ion at both sampling sites and during both seasons, while the lowest concentrations were measured for Br?. Moreover, there were significant relationships between meteorological parameters and ion concentrations. A comparison of the cation and anion equivalence values using seasonal CE/AE (cation equivalence/anion equivalence) ratios showed that the aerosol matter had alkaline characteristics during both seasons. The mean value for the CE/AE ratios was 1.58 in winter and 2.06 in summer at the urban sampling site and 1.36 in winter and 1.52 in summer at the suburban sampling site. The interrelationships among the ions were determined by Pearson correlation analysis. Based on the correlation analyses, the ions emitted from common sources and those exposed to similar atmospheric conditions displayed strong correlations with each other.  相似文献   
739.
Pesticide air pollution by spraying was evaluated under different temperature, humidity and wind climatic conditions in Brazil. Field experiments were performed with application towards the soil and in guava orchards, where spray dispersion was monitored by adding p-aminobenzoic acid (PABA), a fluorescent substance, as a tracer to the water contained in the spray tanks. Samples were collected with filter membranes (Whatman 180025), and the PABA was extracted from the filters by shaking with water in a Petri dish and measured in a spectrofluorometer. A spray aimed towards the soil with filters positioned on the ground and hung at different heights did not show different upward dispersion as observed when lateral pulverization was conducted. In this case, a tractor with a sprayer moved through a 3 m high and 6 m wide frame with filter membranes mounted at 60 cm intervals. Spray dispersion patterns were modified by guava leaf resistance. No influence of temperature and humidity was observed in this short-lived spraying process. Nevertheless, wind drift can occur during airborne dispersion and is an important pesticide pollution source which requires control. Droplets with PABA powered by assisted spraying upwards returned to the ground by gravity and, therefore, did not constitute a vertical source of atmospheric pollution.  相似文献   
740.
This paper offers an analysis of the implementation performance of the EU Ambient Air Quality directive in the Netherlands. It provides a systematic evaluation of the implementation of a procedural provision – the obligation to design air quality policy. It draws on original data on air quality policy measures that have been collected in 13 medium-sized Dutch municipalities. The analysis of differences in the implementation performance was performed using a novel three-dimensional conceptual framework. The findings illustrate great differences in the implementation performance between the municipalities. The focused comparison allowed establishing very precisely where the implementation performance is poor or even lacking, and which municipalities take their EU implementation task more seriously than others. Most puzzling, environmental problem pressure turned out not to act as a sufficient trigger for municipalities to take far-reaching air quality measures. In contrast to previous research, a more nuanced picture is painted when it comes to the concepts of ‘compliance’, ‘non-compliance’ and ‘over-compliance’. A careful dissection of the implementation performance based on the aspects of the conceptual framework produces hands-on recommendations to municipalities seeking to improve their air quality policy.  相似文献   
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