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61.
以电解锰阳极泥与电解锌生产中产生的含SO_2尾气为原料,经过反应、浸出、浸出液两次净化和浓缩结晶制备硫酸锰,考察了反应时间、含SO_2尾气的流量及反应温度对Mn~(4+)转化率的影响.实验结果表明:在反应时间45 min、反应温度20~30 ℃、含SO_2尾气流量16 L/min的条件下,Mn~(4+)转化率达90%以上;尾气中SO_2利用率随尾气流量增加而降低;所得MnSO_4·H_2O产品质量达到GB1622-86<工业级硫酸锰标准>.  相似文献   
62.
生物法同时脱硫脱硝试验研究   总被引:1,自引:0,他引:1  
采用轻质陶粒生物滴滤塔处理摸拟燃煤烟气中二氧化硫和氮氧化物的试验研究,探讨生物法同时脱硫脱硝的影响因素及生物降解宏观动力学。研究结果表明,生物法能有效同时去除烟气中的二氧化硫和氮氧化物,烟气同时脱硫脱硝效率分别可达99.9%和88.9%。为获得最佳烟气同时脱硫脱硝效果,二氧化硫和氮氧化物进气负荷应分别<140 g/(m3·h)和20 g/(m3·h),循环液pH=7~8,空床停留时间为30.28 s,喷淋密度为8.81 L/(m3·h)。  相似文献   
63.
统计2012年10月和11月浦东机场飞机机型和航班架次,根据各类飞机起降的污染物排放设计工作参数,估算出2012年浦东机场飞机起降时排放的NO2、SO2、CO和HC的估算值。利用浦东新区13个空气监测子站二氧化氮和二氧化硫数据绘制等值线图。结果显示,机场所在的江镇点位和祝桥点位二氧化氮浓度变化受飞机影响很大,而飞机排放的二氧化硫对两个点位的影响可以忽略不计。建议采用改进飞机滑行路线、探讨征收飞机碳排放税等措施减少飞机尾气排放对空气质量的影响。  相似文献   
64.
用低浓度SO2诱导驯化方法获得高效脱硫菌群,并用分离培养与16S rRNA基因测序技术相结合的方法鉴定菌群种属,分析驯化过程中种群结构的动态变化,同时研究分离纯菌种的脱硫性能。结果表明,从诱导驯化7 d和14 d菌液中分别分离出23株菌和22株菌,16S rRNA序列分析发现这些菌归属于13个种,其中有6个种(Rhodococcus erythropolis、Pseudomonas putida、Microbacterium oxydans、Sphingomonas koreensis、Acinetobacter junii、Acinetobacter johnsonii)对SO2-3有较强的降解能力,并在持续驯化过程中稳定的生长传代,降解产物以硫酸根为主,还有极少量的单质硫。与含混合菌的驯化菌液降解SO2-3的能力相比,单一脱硫菌的脱硫性能较弱。脱硫功能菌株及其基本特性的研究为微生物处理SO2烟气提供了丰富的菌源信息和理论基础。  相似文献   
65.
为满足石油化工企业总量控制的要求,采取相应的治理措施,降低污染物排放总量,避免采取大量投资和占地的末端治理措施,在工艺过程中采取措施降低主要污染物排放总量是行之有效的途径,采用催化工艺中添加硫转移脱氮剂的办法、热电厂锅炉采用改善炉体燃烧状态、配合石灰石脱硫等工艺过程措施,探讨进一步减少二氧化硫排放总量的可行性。  相似文献   
66.
以黄单胞菌为硫氧化菌种挂膜于生物滴滤塔,研究其去除能力及产物.通过测定压降、生物量确定挂膜时间,以进出气口浓度变化反映去除效率,测定营养液pH值变化,用SEM电镜扫描、能谱分析、X射线衍射对产物进行分析.结果表明,黄单胞菌挂膜时间为4 d,持续运行,菌种均匀地分布于填料表面;保持气体流量为1 L/min,H_2S气体质量浓度在2 000 mg/m~3以下时,去除率大于90.5%,单位体积最大生化去除量为43.23 g/(m~3·h);以10 d为周期添加营养,系统的pH值在5~7;自然沉降得到的黄色颗粒状沉淀粒径为3.161~31.90 μm;能谱分析表面主要成分为C、O、S,应该为微生物和S系物;X射线衍射分析表明干燥粉末的主要无机物质存在形态为S单质.塔在弱酸环境运行,能减少对装置的腐蚀,营养液中通过物理沉降、过滤、低速离心的简单手段,就能回收产物S单质.  相似文献   
67.
Air pollutant concentrations from a monitoring campaign in Buenos Aires City, Argentina, are used to investigate the relationships between ambient levels of ozone (O3), nitric oxide (NO) and nitrogen dioxide (NO2) as a function of NO x (=NO + NO2). This campaign undertaken by the electricity sector was aimed at elucidating the apportionment of thermal power plants to air quality deterioration. Concentrations of carbon monoxide (CO) and sulphur dioxide (SO2) were also registered. Photo stationary state (PSS) of the NO, NO2, O3 and peroxy radicals species has been analysed. The ‘oxidant’ level concept has been introduced, OX (=O3 + NO2), which varies with the level of NO x . It is shown that this level is made up of NO x -independent and NO x -dependent contributions. The former is a regional contribution that equates the background O3 level, whereas the latter is a local contribution that correlates with the level of primary pollution. Furthermore, the anticorrelation between NO2 and O3 levels, which is a characteristic of the atmospheric photo stationary cycle has been verified.The analysis of the concentration of the primary pollutants CO and NO strongly suggests that the vehicle traffic is the principal source of them. Levels of continuous measurements of SO2 for Buenos Aires City are reported in this work as a complement of previously published results.  相似文献   
68.
Air pollution has become an actual problem in Balikesir because of rapid urbanisation and increasing of the polluting sources. Air pollutionproblems occur under the unfavorable meteorological conditions which increase in frequency of occurrence in winter due to use of low quality lignite coals for heating. The `Protection of Air Quality' in Turkey dated 1986 is based on the human health criteria. But the critical limit values are lethal for the forest trees as far as SO2 is concerned. The field observations showed that leaves of the trees have yellow spots indicating acid burns in Balikesir. This study aims at determining the relationships between the SO2 concentrationsin the air under selected climatic conditions, and the effects of air pollution on forest trees in Balikesir. Samples of leaves were collected from the City Parks in Balikesir, Deirmenboaz forested area located 10 km far fromBalikesiron the Balikesir-Bursa highway, and from the forestation areas near the Balikesir-Edremit highway. Sulfur contents of the leaves were very high especially in the city (2650–5300 g m-3).Samples from other areas had values lower than this range but above the usual values (850–3612 g m-3). The diameter increments of the trees were found to be lower and these results clearly showed the adverse impacts. Negative correlations were found between these sulfur concentrations and the daily mean temperatures and wind speeds. Positive correlation was seen between these concentrations and pressures, humidities. Emission sources must be controlled in order to safeguard the forests which protects the soil, facilitate water production, assimilate carbon dioxide in air and produce oxygen. It must be considered that the problems are not only regional but have a global identity.  相似文献   
69.
The size and isotopic behavior of sulfur pools in210Pb-dated peat cores were investigated to obtain aninsight into retention mechanisms of pollutant S in twomountain-top peatlands of the Northern Czech Republic, CentralEurope. The bogs were situated 40 km apart in an area whichbetween the years 1985 and 1995 received as much as 130 kg Sha-1 yr-1 from the atmosphere. Vertical peataccretion was faster at Pod Jelení horou (JH) than atVelký moál (VM). Organic carbon-bonded S was themost abundant sulfur pool, constituting 77 and 65 wt. % at JHand VM, respectively. At JH both the S concentration maximumand the highest annual S deposition rate were displaceddownward by more than 20 years (from 1987 to the 1960s)indicating that the buried S is vertically mobile. At VM the Sconcentration was the highest in the topmost 2-cm section eventhough atmospheric S deposition peaked in 1987. Differentmechanisms of S isotope redistribution prevailed in thetopmost peat layers at JH, where a negative 34Sshift occurred, and at VM, where a positive 34Sshift occurred. Bacterial sulfate reduction was responsiblefor the negative 34S shift at JH. One possibleexplanation of the positive 34S shift at VM isrelease of 32S-enriched products of mineralization duringpeat diagenesis. There was a strong positive correlationbetween the abundance of total and pyrite S along the profiles.The presence of pyrite S at VM (526 ± 60 ppm) suggestedthat even at VM bacterial sulfate reduction occurred. Ananaerobic incubation of JH peat indicated sulfate reductionrate of 600 nmol g-1 day-1. The turnover times forinorganic S pools were shorter than for the organic S pools.Cumulative S contents in the Czech peat bogs were found to besignificantly lower than in similar sites in the NortheasternU.S., even though the atmospheric S inputs were more thanthree times higher at the Czech sites. Possible causes of suchdiscrepancy are discussed.  相似文献   
70.
设计并介绍分户报警与短信群发结合的报警方式,包括系统采用的布局方法、方案总体设计、整体结构、信息传输网络设计;提出分户报警的新报警策略,并给出分户报警的区域划分方法以及划分的理由和依据。在硬件方面,重点介绍分户警铃的方案,其中包括的两个重要组成部分:无线应急广播发射中心和无线应急广播接收设备;提出采用可寻址智能无线广播的新的技术方法,同时给出建议的设备,总结并分析分户报警系统的功能和特点。通过该警报系统的采用,能大大提高警报通知效率,节省疏散所需的时间。  相似文献   
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