首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到18条相似文献,搜索用时 93 毫秒
1.
综述了国内外固定污染源可凝结颗粒物(CPM)冲击冷凝法和稀释冷凝法2种采样方法,指出CPM是固定污染源排放颗粒物的重要组成部分,国内对于固定污染源CPM排放的监测和研究尚处于起步阶段,缺乏必要的CPM采样标准方法。通过分析2种采样方法的优缺点,提出冲击冷凝采样法需进一步降低SO_2等水溶性气体的影响,提高气相CPM冷凝效果及超细颗粒态CPM的捕集效率;稀释冷凝法需提高采样装置的便携性实现可过滤颗粒物(FPM)和CPM的分离采样,提高采样管路壁面颗粒物回收率。同时,针对我国固定污染源如燃煤电厂大量使用湿法脱硫设备的情况,CPM采样方法需提高对低温高湿且夹带液滴烟气采样的适用性。  相似文献   

2.
针对国内固定源大气颗粒物监测技术的现状及不足,通过对资料总结发现国内固定源排放颗粒物的监测技术现状中存在国标精度要求较低和技术细节不足等问题,并重点从分级采样和大气低浓度颗粒物检测方面深入剖析相关技术的不足与需求,并结合国内外的经验,从国标的修订与补充、分级采样技术体系的建立和低浓度大气颗粒物采样方法的改进等3个方面提出技术与设备方面的改进建议。  相似文献   

3.
硫酸雾测试方法若干问题思考   总被引:1,自引:1,他引:0  
简述了我国硫酸雾测试方法的发展历史,分析和总结了《固定污染源废气硫酸雾的测定离子色谱法》(HJ 544—2016)存在的一些争议和问题,包括硫酸雾的定义、测试方法的干扰控制等。分析认为,相比《硫酸工业污染物排放标准》(GB 26132—2010),HJ 544—2016对硫酸雾的定义更加合理。实验结果表明:硫酸盐是测试方法条件下的目标物,滤筒可以显著地捕捉硫酸盐。9组样品滤筒中,被测目标物所占比例为7.9%~69.1%;滤筒和前吸收液中,被测目标物所占比例为93.7%~97.8%。HJ 544—2016新增加的两级串联碱液吸收瓶可以较完全地捕集穿透滤筒后的硫酸雾,同时也会捕集SO2。SO2会对硫酸雾测试产生正干扰,约42.9%的SO2在被吸收后转化为硫酸雾。  相似文献   

4.
利用拉曼光谱对采样后的滤筒进行分析,发现废气中的硫酸铵-硫酸氢铵气溶胶是造成成都市部分企业烟气排放连续监测系统(CEMS)颗粒物比对监测结果不合格的主要原因。通过比较分析得出:在对含硫酸铵-硫酸氢铵气溶胶废气进行颗粒物浓度比对监测时,参比方法(重量法)测定的颗粒物浓度是一定标干采样体积下废气中固体微粒和硫酸铵-硫酸氢铵液体微粒结晶后产生的晶体的总质量,基于光散射法的CEMS颗粒物浓度测试系统测定的颗粒物浓度只是一定标干采样体积下废气中固体微粒的质量,由此导致参比方法测出的颗粒物浓度远大于CEMS测出的浓度,造成比对误差远超出允许值范围。  相似文献   

5.
简述了我国现阶段大气固定污染源颗粒物监测中遇到的问题及低浓度颗粒物采样与分析技术研究的必要性,归纳了国外低浓度颗粒物采样分析技术要点,包括大体积采样、滤筒上游采样设备堆积颗粒物的回收、有效称重步骤的确立等,并对我国开展低浓度颗粒物采样及分析技术研究提出了相关建议.  相似文献   

6.
用玻璃纤维滤筒采集固定污染源废气颗粒物,借助硝酸和氢氟酸的作用,使滤筒和废气颗粒物在160℃下消解,再用原子荧光法测定消解液中总汞。用50%热硝酸溶液处理玻璃纤维滤筒,消除滤筒本底值不一对测定结果的干扰,并优化消解过程,使该方法在0.050μg/L~1.00μg/L范围内线性良好。当采样体积为10 L时,方法检出限为4.5×10~(-5)mg/m~3,空白加标样6次测定结果的RSD为7.2%,加标回收率为87.0%~113%。将该方法用于测定某固定污染源废气颗粒物中总汞,测定值在标准排放限值内。  相似文献   

7.
本法适用于化工厂的排放筒排放的高浓度的硫酸雾(包括SO_3),测定浓度范围广(50—3000毫克/米~3)。用超细玻璃纤维滤筒阻留法等速采样,样品用去离子水加热近沸情况下洗脱,过滤并通过阳离子树脂去除锶、镁、锆、钍等金属离子的干扰。该方法对300mg/m~3以上的样品相对误差在0.5%以下,50—100毫克/米~3的样品相对误差一般在1%左右。  相似文献   

8.
通过采用玻璃纤维滤筒采集、吸收液吸收和S材料滤筒采样三种不同采集原理的油烟采样方法的试验,研究出一种油烟采样新材料--SM材料,其填充后制成的S材料滤筒的油烟采集效率大于96%的采样方法.  相似文献   

9.
铬酸钡分光光度法测固定污染源中硫酸雾刘拴丽(陕西省渭南市环境监测站,渭南714000)本文对统一分析方法作如下改进:①利用氯化钡与铬酸钾等摩尔反应生成铬酸钡沉淀物为显色剂,操作简单。②预处理时将滤筒放入250ml锥形瓶中,加100ml水浸没后用玻棒捣...  相似文献   

10.
以赤市2种采样方法获得的数据为基础,运用数据统计中的双因素方差法及一元线性回归法对2种采样方法的相关性进行了验证。结果表明,连续采样法代替五日手工采样法后,对于SO2、NOx2种方法之间无显著差异,对于TSP两方法的延续性很差。  相似文献   

11.
采用玻璃纤维滤筒采集工业废气中铍及其化合物,硝酸-氢氟酸混酸体系微波消解滤筒、硝酸镁一硝酸混合液作为基体改进剂,石墨炉原子吸收法测定铍。本方法前处理操作过程简单、省时、酸用量少、环境污染小,方法的灵敏度和准确度都有很大的提高。当采样体积为30L,工业废气中铍的最低检出质量浓度为1×10μmg/m^3。  相似文献   

12.
In this paper we demonstrate the use of SPE cartridges for sampling of organophosphate triesters in indoor air by adsorptive enrichment. The method has been optimised for the sampling and analysis of organophosphate triesters using a 25 mg aminopropyl silica SPE cartridge. The same cartridge is used for the active air sampling as well as for the subsequent extraction and clean-up of the sample. This makes the method fast and eliminates some tedious and time-consuming manual sample handling steps. Sampling and extraction efficiency was high for the investigated organophosphates, and limit of detection was in the range 0.1-0.3 ng m(-3). The method was applied to measurements of organophosphate triesters in two lecture halls and an electronics dismantling facility, and was compared with results from common filter/adsorbent sampling at each site. Analysis was made by GC with selective detection by NPD set in phosphorus mode, and by GC-MS. Thirteen organophosphate triesters (not counting isomers) were detected in the electronic dismantling facility. Chlorinated organophosphate triesters were detected in all locations with concentrations over 1 microg m(-3) in the lecture halls. This kind of adsorptive enrichment using an SPE cartridge could be adjusted to other types of analytes as well.  相似文献   

13.
The dialdehyde glyoxal (ethanedial) is an increasingly used industrial chemical with potential occupational health risks. This study describes the development of a personal sampling methodology for the determination of glyoxal in workroom air. Among the compounds evaluated as derivatizing agents; N-methyl-4-hydrazino-7-nitrobenzofurazan (MNBDH), 1,2-phenylenediamine (OPDA), 1-dimethylaminonaphthalene-5-sulfonylhydrazine (dansylhydrazine, DNSH) and 2,4-dinitrophenylhydrazine (DNPH), DNPH was the only reagent that was suitable. Several different samplers were evaluated for sampling efficiency of glyoxal in workroom air using DNPH as derivatizing agent; in-house DNPH coated silica particles packed in two different types of glass tubes, impingers containing acidified DNPH solution, filter cassettes containing glass fibre filters coated with DNPH, a commercially available solid phase cartridge sampler originally developed for formaldehyde sampling (Waters Sep-Pak DNPH-silica cartridge), and the commercially available SKC UMEx 100 passive sampler originally developed for formaldehyde sampling. Aldehyde atmospheres for sampler evaluation were generated with an in-house made vapour atmosphere generator coupled to a sampling unit, with the possibility of parallel sampling. The resulting glyoxal-DNPH derivative was determined using both LC-UV and LC-APCI-MS with negative ionization. By far, the highest recovery of glyoxal was obtained employing one of the in-house DNPH coated silica samplers (93%, RSD = 3.6%, n = 12).  相似文献   

14.
目前,对固定污染源废气中磷酸雾的检测并无统一的方法,相关含磷污染物的控制指标主要是磷化氢、单质磷以及五氧化二磷。在调研国内外分析方法及相关文献的基础上,通过对几种典型含磷污染源的实样测试,提出了固定污染源废气中磷酸雾的检测方法。结果表明,使用石英滤筒捕集固定污染源废气中的磷酸雾,采样效率可达98%以上。捕集到的总磷酸雾不仅包含磷酸,还包含磷酸盐以及含磷氧化物等,是一项综合指标。该指标能够反映含磷污染物的排放特征,可为未来此类污染物的排放控制提供依据。  相似文献   

15.
建立连续流动注射间接测定空气中五氧化二磷的方法。空气中的五氧化二磷用过氯乙烯滤膜或滤筒采样,加入去离子水反应生成正磷酸,过滤、洗涤、定容后运用连续流动注射仪进行测定。优化了抗坏血酸浓度、硫酸浓度、钼酸盐浓度以及恒温室温度等影响显色的因素。最佳条件下,实际样品五氧化二磷加标回收率为96.0%~102%,相对标准偏差在4%以下;采样体积为300 L时,方法检出限为0.001 6 mg/m~3。t检验结果表明,所建方法与现行国标法的测定结果无显著性差异。方法分析速度快、重现性好、灵敏度高,适用于空气中五氧化二磷的测定。  相似文献   

16.
An overview is presented of sampling techniques and flow injection analysis (FIA) methods for low concentrations of Fe, Mn and Al in filtered seawater. On the basis of sampling procedures, filtration techniques, accuracy, blanks, detection limits, intercalibration results and oceanographic consistency, the feasibility of these FIA methods was evaluated. It was found that these metals could be measured on board with a minimum risk of contamination and with good accuracy even at low subnanomolar levels (<0.5 nM). Results for reference seawater were in the case of Fe-FIA and Mn-FIA in excellent agreement with the certified values. Data from samples analyzed by Fe-FIA and by cathodic stripping voltametry (CSV) compared well, as did Mn-FIA and GFAAS. All three methods gave results that were mostly in good agreement with data from the same ocean regions published by other research groups. Two different types of surface water sampling were also tested and compared, namely conventional hand filling of a sample bottle from a rubber dinghy away from the ship, and underway pumping of seawater using a 'tow fish'. The latter method gave the best results. Also, conventional membrane filtration and cartridge filtration for large volume filtration were compared using Fe and Al data from water column samples. Good agreement was found for both filter types, although for defining dissolved metal species the latter filter type was preferred.  相似文献   

17.
根据PM2.5中重金属监测国标分析方法,从PM2.5采样方法、采样保存条件、滤膜材质性能等方面说明利用空气自动采样滤膜监测PM2.5中铅和镉是可行的;对手工采样(石英滤膜)和Beta射线法自动采样(自动采样滤膜)2种方法,对PM2.5实际样品中铅和镉的结果进行比较,结果显示:自动采样滤膜的空白检出和检出限均满足铅和镉的监测需求,铅和镉的回收率分别为95.2%~107%和91.8%~105%,与手工采样方法相比测得铅和镉的相对误差分别为3.6%~8.4%和1.3%~10.8%,从实践角度进一步证明了利用自动采样滤膜对PM2.5中铅和镉进行监测是可行的。  相似文献   

18.
The objective of this study was to determine filter materials and extraction methods that are appropriate to use for environmental sampling of B. anthracis. Four types of filters were tested: mixed cellulose ester (MCE) with a pore size of 3 microm, polytetrafluoroethylene (PTFE) with pore sizes of 1 and 3 microm, and gelatin with a pore size of 3 microm. Bacillus subtilis var. niger endospores (also known as Bacillus globigii[BG]) were used as a surrogate for B. anthracis. Endospores were collected into Button Inhalable Aerosol Samplers with sampling times of 15 minutes, 1 hour, and 4 hours. Physical collection efficiency was determined by measuring upstream and downstream B. subtilis concentrations with an optical particle counter. Vortexing with ultrasonic agitation and vortexing with shaker agitation extraction methods were evaluated. The MCE, 1 microm PTFE, and gelatin filters provided physical collection efficiencies of 94% or greater. The 3 microm PTFE filter showed inconsistent physical efficiency characteristics between filters. Epifluorescence microscopic analysis of the gelatin filter extraction fluid revealed the presence of contamination by non-culturable bacteria. Mean differences for microbial culturability were not statistically significant for filter materials and extraction methods. However, the vortexing with shaker agitation extraction method resulted in higher total microbial counts in the extraction fluids for MCE and 1 microm PTFE filters when compared to vortexing with ultrasonic agitation. In summary, the MCE and 1 microm PTFE filters in combination with vortexing and shaker extraction demonstrated the best performance for the filter collection and extraction of BG spores.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号