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1.
基于全国空气质量监测网数据,分析2015—2020年昌吉市O3-8h污染状况.结果表明:2015—2020年昌吉市O3-8h和O3-8h-90% 平均浓度为74、113μg/m3,整体呈上升趋势,相比2015年,2020年O3-8h和O3-8h-90% 浓度升高了19、27μg/m3,近4 a来昌吉市O3-8h-90%...  相似文献   

2.
南京市冬季大气颗粒态汞的分布特征   总被引:2,自引:0,他引:2  
采集了南京市2012年冬季4个功能区的PM2.5、PM10、TSP样品,对不同粒径大气颗粒物中的颗粒态汞测试。结果表明,南京冬季大气颗粒物TSP中汞的质量浓度为49.26 pg/m3~257.14 pg/m3,平均质量浓度为161.27 pg/m3;PM10中汞的质量浓度为44.82 pg/m3~228.29 pg/m3,平均质量浓度为147.38 pg/m3;PM2.5中汞的质量浓度为35.98 pg/m3~178.58 pg/m3,平均质量浓度为104.10 pg/m3。不同功能区大气颗粒态汞质量浓度的分布趋势为:交通综合区>旅游区>住宿综合区>商业区。大气颗粒态汞60%以上存在于可吸入肺的PM2.5中,细颗粒物富集汞的能力比粗颗粒物强。  相似文献   

3.
采用菰草(Latifolia griseb)滤床净化模拟村落污水尾水的实验表明,以污染物去除负荷最大值确定滤床的水力负荷为0.9m3/m2·d,此运行条件下水生植物滤床对TN、TP、COD。,的去除率分别为33.5%、39.2%、22.8%;以出水可达《城镇污水处理厂污染物排放标准》(GB18918-2002)一级A排放标准确定水力负荷应不大于0.3m3/m2·d,此条件下TN、TP的去除率分别为52.2%、58.3%。菰草滤床适宜栽培水深为15~25cm。  相似文献   

4.
以福建省某化工危险废物处理工程为例,研究固态危废焚烧处置设施的技术性能。工程采用高温涡流燃烧+二燃室+水冷除尘器+急冷塔+干式吸附+布袋除尘+喷淋吸附+雾水分离工艺,设计处理量为100 kg/h。研究结果表明:在测试工况下,二燃室温度为(1 149.6±13.4)℃;烟气在炉膛的平均停留时间为(5.35±0.12)s,燃烧效率为99.97%;萘与CCl4的焚毁去除率分别为99.996%与99.991%,热灼减率为3.3%;焚烧设施的技术性能达到《危险废物焚烧污染控制标准》(GB 18484—2020)的要求;二噁英的排放值为0.007 6 ngTEQ/m3,HF和CO的排放值分别为1.21 mg/m3和72.8 mg/m3,烟气排放达标。  相似文献   

5.
采用 SUMMA罐采集空气样品,在预浓缩系统中经3级冷阱捕集后,用气相色谱-质谱联用技术测定环境空气中7种痕量有机硫化物。对试验条件进行优化,使得甲硫醇、乙硫醇、甲硫醚、二硫化碳、噻吩、乙硫醚和二甲二硫醚等7种有机硫化物在21.47μg/m3~336.43μg/m3范围内线性良好。试验表明,7种有机硫化物的方法检出限为0.004μg/m3~0.036μg/m3;标准气体平行测定6次结果的 RSD为2.7%~6.2%,加标回收率为92.2%~97.5%。用该方法测定实际空气样品,并与傅立叶红外光谱法测定的结果进行比对,结果令人满意。  相似文献   

6.
离子色谱法测定空气中氟化氢氯化氢和硫酸   总被引:1,自引:0,他引:1  
以多孔玻板吸收管采样,采用离子色谱法同时测定作业场所空气中的氟化氢、氯化氢和硫酸,采样效率>92%。氟化氢在0 mg/L~2.00 mg/L、氯化氢在0 mg/L~2.50 mg/L、硫酸在0 mg/L~4.00 mg/L范围内线性良好,检出限分别为0.003 mg/m3、0.02 mg/m3、0.023 mg/m3(按采样体积60 L计),标准溶液平行测定的RSD≤8.0%,两个质量浓度水平加标的平均回收率为92.6%~106%。  相似文献   

7.
采用微波消解电感耦合等离子体发射光谱法同时测定废气中的铅、镉、砷,在优化的试验条件下,方法在0 mg/L~5.00 mg/L范围内线性良好,铅、镉、砷的检出限分别为0.250 μg/m3、0.125 μg/m3、0.375 μg/m3(按采样体积400 L、定容体积50 mL计),空白滤筒平行测定6次的RSD为2.3%~10.5%,加标回收率为83% ~ 112%,与标准方法的测定结果无显著差异.  相似文献   

8.
全二维气相色谱/飞行时间质谱联用监测环境空气中VOCs   总被引:2,自引:0,他引:2  
采用全采样系统-全二维气相色谱/飞行时间质谱联用技术监测环境空气中的VOCs,优化了调制周期、升温程序、进样体积等分析条件.39种目标化合物在0 μg/m3~10.0 μg/m3范围内线性良好,检出限范围为0.03 μg/m3~0.09 μg/m3,标准气体平行测定的RSD为1.1% ~5.3%.应用于化工园区环境空气样品测定,与热脱附-气相色谱/质谱法相比,目标物的分离效果更佳.  相似文献   

9.
采用HP-INNOWAX毛细管柱、气相色谱氢火焰离子化检测器测定工业废气和废水中的N,N-二甲基甲酰胺,可能共存的丙酮、乙醇和乙酰丙酮均对测试无干扰.方法在0.939 mg/L~75.1 mg/L范围内线性良好,对工业废水、无组织排放工业废气和有组织排放工业废气中N,N-二甲基甲酰胺的检出限分别为0.47 mg/L、0.16 mg/m3和0.31 mg/m3,标准溶液平行测定的RSD为1.9% ~2.2%,废水样品加标回收率为94%~ 97%.  相似文献   

10.
一种评估烟花爆竹燃放对大气PM2.5影响的新方法   总被引:5,自引:1,他引:4  
基于北京市空气质量自动监测系统2013年2月常规污染物监测数据,提出了定量估算烟花爆竹燃放对大气PM2.5影响的污染物相对比值(PM2.5/CO)法。利用该方法研究表明,2013年北京除夕烟花爆竹燃放使PM2.5单站1小时平均浓度最大增加709μg/m3(石景山古城监测点);全市24小时平均浓度增加88μg/m3,达到159μg/m3,空气质量由良好升级为重度污染。元宵节夜间烟花爆竹燃放使PM2.5单站1小时平均浓度最大增加469μg/m3(海淀万柳监测点),全市24小时平均浓度增加54μg/m3。除夕夜、元宵夜全市平均烟花爆竹PM2.5浓度超过75μg/m3的时间分别为5、7 h,达到峰值后半衰期分别为0.9、1.7 h。城区烟花爆竹PM2.5浓度高于郊区,并可导致下风向郊区的PM2.5浓度显著增加。除夕、元宵节北京市区烟花爆竹排放PM2.5总量分别约为1.91×105kg、1.17×105kg。  相似文献   

11.
以污水厂长序列运行数据为基础,反推脱氮实际影响因素,开展反硝化脱氮试验.结果表明,在2019年4月前后TN出水平均浓度降低58%;受季节和污水厂升级改造影响,温度由15℃升高至25℃,混合液悬浮固体质量浓度(MLSS)由4300 mg/L增至8000 mg/L,活性污泥成分增加,脱氮效果提升;BOD5/TN和pH值等变...  相似文献   

12.
In this study, the variation of sewage quality was investigated and the active fraction of different microbial functional groups in biofilm was quantified in a 5.6-km trunk sewer line. The sewage quality including suspended solids, biochemical oxygen demand, total chemical oxygen demand (COD), total nitrogen, total Kjeldahl nitrogen, ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen were measured and compared with the values in literatures. The results indicated that since the wastewater treatment plant was not operated at its full capacity, the concentrations of different compounds were lower compared with the values in literatures. The values of heterotrophic growth rate constant lay between 5.6 and 8.6 day???1. Its average value was 7.7 day???1. The values of heterotrophic lysis rate constant lay between 0.2 and 0.4 day???1. The active heterotrophic biomass in biofilm varied from 240 to 800 mg COD m???2 and average value was 497 mg COD m???2. The biofilm mass varied from 880 to 1,080 mg m???2. The percentage of heterotroph to biofilm mass fall within the range of 24.0–90.9% and average value was 52.9%. In the oxygen uptake rate batch tests, the biomass, growth rate constant, and lysis rate constant of autotroph could not be determined because the fraction of autotroph in biofilm was relatively few. It revealed that the degradation of organic matters, nitrification, and denitrification occurred in the trunk sewer line. But the results indicate that the condition seem favorable for nitrification.  相似文献   

13.
An anoxic biofilm involved in continuous denitrificationprocess was monitored to investigate the effect of differentconcentrations of influent dissolved oxygen (DO) or nitrite onthe biofilm. Microelectrode measurements evidenced nitrateremoval activity of biofilm. When different concentrations ofDO were applied to the reactor, generally decreasedconcentrations of DO were observed as bed depth increased fromthe bottom of the reactor. Greatest decrease of the DO wasobserved in the lower 20% of the bed depth. Nitrate removalefficiency was inversely proportional to influent DOconcentrations (8.3-11.9 DO mg L-1) or nitrite loadingrates (0-5.5 N-NO2 - kg m-3 day-1) employed in this study. Nitrite loading rates to achieve morethan 90% of nitrate removal efficiency were 1.46 N-NO2 -kg m-3 day-1 or less at pH 7.5 and 0.34 N-NO2 - kg m-3 day-1 or less at pH 6.8. Nitrate removal efficiency was 63% or more within the lower 20% of the bed depth at the nitrite loading rates that allowed more than 90% of nitrate removal efficiency of the reactor. The results of this study provide first quantitative data that nitrate removalperformance of an anoxic biofilm is inhibited by DO or nitrite,reported to be a limiting factor in the suspended biologicaldenitrification process.  相似文献   

14.
In this research, two types of sequencing batch reactors (SBRs) with 8 h of cycle times, namely non-powdered activated carbon (NPAC-SBR) and powdered activated carbon (PAC-SBR), were used for the treatment of raw leachates at Kulim and Pulau Burung landfill sites. To test the performance of SBRs, phenols, total iron, zinc, ammonia, nitrite, nitrate, color, suspended solids, chemical oxygen demand, biochemical oxygen demand, and total dissolved salts removal efficiencies and sludge volume index (SVI) were studied at both sites. The rates of phenols removal, for instance in NPAC-SBRs and PAC-SBRs at Kulim, were 25% and 55%, respectively, whereas those at Pulau Buring were 94.81% and 97.75%, respectively. PAC as adsorbent in PAC-SBRs enhanced the removal efficiencies of the aforementioned pollutants from leachates at both sites. In addition, PAC as adsorbent decreased the SVI values at Kulim (59.7 mL/g) and Pulau Burung (91.4 mL/g) leachates and improved the nitrification and denitrification processes.  相似文献   

15.
A novel technology for the removal of nitrogen from wastewater, autotrophic denitrification process with sulfur particle, has been developed. A respirometer was employed for the monitoring of nitrogen gas produced in the reactor. It was found that the autotrophic denitrification studied by gas production rate and nitrate depletion rate followed a first order reaction from the relationship. The reaction rate constant based on effective volume, kN was ranged from 2.67 to 3.07 h–1. The effective height was around 23.8 and 50% of the total height for 11.8 and 5.9 h of packed bed contact time, respectively. It was assumed that the reaction rate constants were similar in each experimental condition, PBCT = 11.9 and 5.9 h because there was little gradient of biomass concentration within 50% of the total height. The respirometry was found to be a simple and fast way to monitor the denitrification process. The method was especially useful for the determination of kinetic parameters.  相似文献   

16.
通过对系统渗透系数及氮素浓度变化的长期监测,考察长期污水处理条件下无植物生物滞留池(Biological Re-tention Cell,BRC)渗透性能及脱氮性能之间的变化规律.结果表明,无植物BRC在长期污水处理运行过程中,TN去除率随着渗透系数的降低而降低.脱氮效率降低是由于系统内基质堵塞导致,渗透系数降低是由于...  相似文献   

17.
Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) in Delhi were evaluated to study particulate PAHs profiles during the different seasons of 2003. Samples of urban suspended particulate matter were collected during January 2003 to December 2003 at three locations (Okhla, Dhaulakuan and Daryaganj), using a high volume sampler provided with glass fiber filters. Samples were analyzed using the gas chromatography technique. The annual average concentrations of total PAHs were found as 1,049.3 ng/m(3) at Okhla, 1,344.37 ng/m(3) at Daryaganj, and 1,117.14 ng/m(3) at Dhaulakuan. The seasonal average concentrations were found to be maximum in winter and minimum during the monsoon season. Principal Component Analysis (PCA) of the data was also carried out and the results indicate that diesel and gasoline driven vehicles are the principal sources of PAHs at all the three sites under investigation. Other sources might come from stationary combustion sources such as cooking fuel combustion and industrial emission.  相似文献   

18.
This study presents a full-scale performance of a natural treatment system (NTS) facility in Taiwan with nearly 2 years of observations. The study site, composed of several treatment ponds in series, was designed primarily to reduce polluted stormwater runoff from tea gardens and partially to untreated domestic wastewater from nearby villages. Thus, both nonpoint source and point source pollution are treated in this system. From 28 field samplings in 2006-2007, the NTS site shows satisfactory treatment performance and the effluent water quality is significantly improved. Seven of the 28 sampling events are storm events (nonpoint source pollution) and the remainder are from regular monitoring (point source pollution). The average volume of influent and effluent is 533 CMD and 196 CMD, respectively. In order to determine the removal efficiency, several assessment measures are employed in an attempt to obtain unbiased conclusions. They are removal rate (RR), efficiency rate (ER), summation of loads (SOL), flux rate (FR), and effluent probability method (EPM). The average percent removal efficiency of NH(3)-N is 53.5-75.2% and of TP is 59.0-84.7%, in which the highest result is calculated by SOL method and the lowest rate is obtained from RR. In FR evaluation, larger treatment capacity for NH(3)-N than for TP is provided in the site and the average FR is respectively 0.230 g/m(2) day and 0.017 g/m(2) day. Of the methods examined, EPM is the only method capable of illustrating data distribution. Finally, recommendations on the usefulness of these measures are summarized to facilitate the understandings of NTS performance evaluations.  相似文献   

19.
There is an increasing need to monitor concentrations of polar organic contaminants in the aquatic environment. Integrative passive samplers can be used to assess time weighted average aqueous concentrations, provided calibration data are available and sampling rates are known. The sampling rate depends on environmental factors, such as temperature and water flow rate. Here we introduce an apparatus to investigate the sampling properties of passive samplers using river-like flow conditions and ambient environmental matrices: river water and treated sewage effluent. As a model sampler we selected Empore SDB-RPS disks in a Chemcatcher housing. The disks were exposed for 1 to 8 days at flow rates between 0.03 and 0.4 m s(-1). Samples were analysed using a bioassay for estrogenic activity and by LC-MS-MS target analysis of the pharmaceuticals sulfamethoxazole, carbamazepine and clarithromycin. In order to assess sampling rates of SDB disks, we also measured aqueous concentrations of the pharmaceuticals. Sampling rates increased with increasing flow rate and this relationship was not affected by the environmental matrix. However, SDB disks were only sampling in the integrative mode at low flow rates <0.1 m s(-1) and/or for short sampling times. The duration of linear uptake was particularly short for sulfamethoxazole (1 day) and longer for clarithromycin (5 days). At 0.03 m s(-1) and 12-14 degrees C, the sampling rate of SDB disks was 0.09 L day(-1) for clarithromycin, 0.14 L day(-1) for sulfamethoxazole and 0.25 L day(-1) for carbamazepine. The results show that under controlled conditions, SDB disks can be effectively used as passive sampling devices.  相似文献   

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