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1.
为了解石家庄市2016年春季大气颗粒物的铅污染特征及来源,利用单颗粒气溶胶质谱仪(SPAMS),分析了大气中含铅颗粒的化学成分。结果表明: 研究期间大气环境中含铅颗粒数浓度共出现11次跳跃式升高,跳跃时间段内石家庄均处于轻度污染过程。从成分分析来看,含铅颗粒分为纯铅颗粒、Pb与K(Pb-K)、OC(Pb-OC)、Cl(Pb-Cl)、混合颗粒等八大类。观测结果表明:Pb-K颗粒最多,占到含铅颗粒的84.4%;其次为纯铅颗粒,占比为13.0%。与石家庄市污染源谱库比对进行来源解析,得到Pb-K颗粒主要来自生活垃圾焚烧源, 纯铅颗粒主要来自工业源。结合石家庄市大气污染源排放清单和后向气流轨迹分析,推测含铅颗粒可能来自市区西南方向某区县的生活垃圾焚烧企业。  相似文献   
2.
The sorption of Cu(II) from an aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. Sorption was investigated as a function of pH, ionic strength, foreign ions, humic substances, and temperature. The results indicate that the sorption of Cu(II) on ZSM-5 zeolite is strongly dependent on pH. Sorption is dependent on ionic strength at low pH, but independent of ionic strength at high pH values. The presence of humic/fluvic acid (HA/FA) enhances the sorption of Cu(II) on ZSM-5 zeolite at low pH values, and reduces Cu(II) sorption at high pH values. Sorption isotherms were well simulated by the Langmuir model. Thermodynamic parameters (i.e., deltaH0, deltaS0 and deltaG0) for the sorption of Cu(II) were determined from temperature-dependent sorption isotherms at 293.15, 313.15, and 333.15 K, respectively. Results indicate that the sorption process of Cu(II) on ZSM-5 zeolite is spontaneous and endothermic.  相似文献   
3.
本文通过对呼和浩特市创建国家环保模范城市面临的困难、采取的措施以及取得的效果进行分析,对北方地区创建国家环保模范城市提供借鉴.  相似文献   
4.
颗粒物污染是影响中国城市空气质量的首要因素。工业料堆扬尘是城市大气颗粒物污染的主要来源之一。本文通过对呼和浩特市建成区内典型行业风蚀、作业及交通运输扬尘进行采样分析,应用美国AP-42提供的模型,以2006年作为基准年,建立了呼和浩特市工业料堆排放清单。研究结果表明:呼和浩特市建成区内工业料堆扬尘排放量为TSP:5 305 t/a,PM10:1 012 t/a,PM2.5:267 t/a。从空间分布看玉泉区工业料堆扬尘排放量最大,其次是赛罕区。行业分布上排放最大的行业是建材工业,其次是电力热力工业,最少的是化工工业。在各行业类别的工业料堆排放量中,交通运输扬尘排放量是最大的。  相似文献   
5.
工业锅炉PM2.5产排特性试验研究   总被引:1,自引:0,他引:1  
采用荷电低压颗粒撞击器(ELPI)对哈尔滨市两台燃用烟煤的工业锅炉PM2.5排放特性进行了研究.研究结果表明:PM2.5的粒数和质量浓度分布曲线均呈现单峰分布,前者峰值出现在0.12~0.2μm粒径范围内,这部分粒子主要是由无机物气化-凝结形成的亚微米颗粒物和挥发分未完全燃烧形成的炭黑粒子,而后者峰值出现在0.32μm处,粒子主要是由炭黑粒子形成的亚微米颗粒和残灰粒子形成的超微米颗粒.同时发现,旋风除尘和湿法除尘对PM2.5各级颗粒均有一定的去除效果,采用多管旋风和冲击水浴除尘器联合除尘效率比单种水膜除尘器除尘效率高;湿法脱硫系统对PM2.5的脱除也有明显的作用,由于除雾器不能全部去除小雾滴,这些雾滴中固体颗粒被干燥和水溶性物质结晶析出,PM0.32颗粒物粒数浓度有所增加,而PM0.32~2.5的颗粒物粒数浓度有所减少,但总质量浓度降低.  相似文献   
6.
污水污泥在富氧环境下燃烧特性的实验研究   总被引:4,自引:0,他引:4  
采用综合热分析仪研究了空气气氛和富氧气氛下污水污泥和煤的燃烧曲线,分析比较氧浓度对污泥燃烧特性参数的影响,并计算得到各工况下的动力学参数。结果表明:随着氧浓度增加,污泥燃烧DTG曲线向低温区移动,着火温度和燃尽温度均降低,综合燃烧指数大大提高,污泥燃烧特性得到改善。可用两段一级反应动力学模型来较好的描述污泥的主要燃烧过...  相似文献   
7.
浙江省象山东部的开阔海域接纳沉积了长江和浙北沿岸经济发达地区包括重金属污染物在内的入海物质.为全面了解象山近海沉积物重金属污染状况,基于2017年夏季54个采样点表层沉积物测试资料,分析其中Cr、Cu、Zn、Pb、Hg、As、Cd等7种重金属元素的分布特征、影响因素和主要来源,并应用地质累积指数法和潜在生态风险指数法对重金属元素进行污染状况和生态风险评价.结果表明:研究区Cr、Cu、Zn、Pb、Hg、As、Cd平均质量分数分别为89.860、36.890、108.740、32.150、0.041、6.090和0.134 μg/g,研究区中部和韭山西北侧海域表层沉积物中的重金属含量较高,近岸区域和东南部外海区域含量较低.Cr、Cu、Zn、Pb、Cd受控于粒度和有机质分布,均以陆源输入为主;Hg、As以其他物质来源为主.主成分分析法将全部因子概括为3个主成分.地累积指数评价结果表明,象山近海表层沉积物中Cu和Cd属轻度污染;研究区中部大片区域具有中等潜在生态风险,主要生态风险因子为Hg和Cd.研究显示,象山近海仍以陆源输入型重金属污染物为主,同时受到海洋水动力、理化条件以及人类用海活动的影响.   相似文献   
8.
A hybrid selective noncatalytic reduction/selective catalytic reduction (SNCR/SCR) system that uses two types of technology, low-temperature SCR process and SNCR process, was designed to develop nitrogen oxide (NOx) reduction technology. SCR was conducted with space velocity (SV) = 2400 hr?1 and hybrid SNCR/SCR with SV = 6000 hr?1, since the study focused on reducing the amount of catalyst and both achieved 98% NOx reduction efficiency. Characteristics of NOx reduction by NH3 were studied for low-temperature SCR system at 150 °C using Mn-V2O5/TiO2 catalyst. Mn-added V2O5/TiO2 catalyst was produced, and selective catalyst reduction of NOx by NH3 was experimented. NOx reduction rate according to added Mn content in Mn-V2O5/TiO2 catalyst was studied with varying conditions of reaction temperature, normalized stoichiometric ratio (NSR), SV, and O2 concentration. In the catalyst experiment according to V2O5 concentration, 1 wt.% V2O5 catalyst showed the highest NOx reduction rate: 98% reduction at temperature window of 200~250 °C. As a promoter of the V2O5 catalyst, 5 wt.% Mn was added, and the catalyst showed 47~90% higher efficiency even with low temperatures, 100~200 °C. Mn-V2O5/TiO2 catalyst, prepared by adding 5 wt.% Mn in V2O5/TiO2 catalyst, showed increments of catalyst activation at 150 °C as well as NOx reduction. Mn-V2O5/TiO2 catalyst showed 8% higher rate for NOx reduction compared with V2O5/TiO2 catalyst in 150 °C SCR. Thus, (5 wt.%)Mn-(1 wt.%)V2O5/TiO2 catalyst was applied in SCR of hybrid SNCR/SCR system of low temperature at 150 °C. Low-temperature SCR hybrid SNCR/SCR (150 °C) system and hybrid SNCR/SCR (350 °C) showed 91~95% total reduction rate with conditions of SV = 2400~6000 hr?1 SCR and 850~1050 °C SNCR, NSR = 1.5~2.0, and 5% O2. Hybrid SNCR/SCR (150 °C) system proved to be more effective than the hybrid SNCR/SCR (350 °C) system at low temperature.

Implications:?NOx control is very important, since they are the part of greenhouse gases as well as the cause of acid rain and ozone hole. A technology, so-called hybrid SNCR/SCR process, was tested using Mn-V2O5/TiO2 monolithic catalyst for NOx reduction, and the method is promising. The results of this study would provide some ideas to parties such as policy makers, environmental engineers, and so on.  相似文献   
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10.
IMPLICATIONS: During the production of penicillin, a mass of waste bacterial residue is generated. In the past, the bacterial residues have been used for food additives. Unfortunately, doubts of their suitability as a feedstock have been raised because of the small amount of antibiotics and the degradation products remaining in the bacterial residues. So, penicillin bacterial residue is one of the hazardous wastes. Therefore, penicillin bacterial residue should be managed in accordance with the hazardous waste. To get a right method, the penicillin bacterial residue was characterized.  相似文献   
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