影响滤筒分析质量的主要因素和改进方法

介绍了影响滤筒称量恒重的原因,指出空气湿度、冷却时间和烘干时间等对滤筒称量恒重都有影响。提出使用标准空白滤筒、在平衡室中冷却、称量滤筒、并采用专用滤筒盒和刚玉滤筒采样减小系统误差。     

不同滤筒中无机元素含量探讨

选择国内10家制造商的玻璃纤维滤筒和国外2家制造商的石英滤筒,分别测定空白滤筒中的铍、铬、铅等17种元素,探讨不同滤筒中各元素的含量分布,同时结合相关分析方法标准的质控要求,评价各制造商玻璃纤维滤筒在废气监测中的适用性。     

烟尘监测时采样滤筒的质量控制

介绍了合格滤筒的筛选方法和采样滤筒在实验室分析中的质量控制,分析了影响滤筒称量恒重的原因,指出空气湿度、冷却时间和烘干时间对滤筒称量恒重都有影响.     

解决滤筒不粘压环的方法

方法 1 :将装好滤筒的采样管背向气流放在采样点上预热 5至 1 0 min,估计滤筒的温度大致上升到烟气温度 ,即可开始采样。这种方法虽好 ,但不足之处是 ,浪费的时间长。同时也增加了扶采样管的人的工作量。方法 2 :在安装滤筒前 ,用布将滤筒的压环和滤筒夹的口部 ,认真地擦几遍 ,直到擦试干净为止 ,即可装滤筒开始采样。这种方法较容易掌握 ,且操作简单 ,建议大家一试。解决滤筒不粘压环的方法@王启华$焦作市中州铝厂安环处!河南焦作454174     

高通量固定污染源废气颗粒物中总汞的测定

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。     

植物油烟组分的色质联机分析

将植物油烟采集在玻璃纤维滤筒中 ,用环己烷处理样品 ,样品经过净化处理 ,然后进行色质联机分析。对油烟化学成分的分析有助于人们研究油烟对人体健康的影响     

烟尘测试中滤筒称重问题

烟尘测试中滤筒称重问题张萍萍（福建龙岩地区环境监测站，龙岩３６４０００）①当滤筒放入天平称重时，滤筒湿度较天平内空气湿度小，产生吸湿现象，天平显示不稳。实验表明，最初称量的５个滤筒应放回干燥器内重新干燥、重新称量。②干燥时间的确定：实验表明，在内径为...     

影响滤简分析质量的主要因素和改进方法

介绍了影响滤简称量恒重的原因，指出空气湿度、冷却时间和烘干时间等对滤简称量恒重都有影响。提出使用标准空白滤筒、在平衡室中冷却、称量滤筒、并采用专用滤简盒和刚玉滤筒采样减小系统误差。     

微波消解石墨炉原子吸收法测定工业废气中铍及其化合物

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。     

不同采集原理的油烟采样方法研究

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.     

State estimation in wastewater engineering: Application to an anaerobic process

The use of an extended Kalman filter for state estimation in biological wastewater treatment processes is discussed. The application of the technique requires an adequate mechanistic dynamic model and the identification and modelling of the major sources of stochastic disturbances in the process. The filter allows the on-line tracking of process variables which are not directly measurable. The use of an extended Kalman filter is illustrated through a simulated application to a high rate anaerobic wastewater treatment process.     

X射线荧光光谱分析空气滤膜颗粒物中多种元素

采用X射线荧光光谱分析空气滤膜采集悬浮颗粒物中的多种元素,样品不需要前处理,不使用试剂,测量1个样品中40余种元素约耗时1 h。重复测量10次NIST SRM 2783空气滤膜标准样品,多数元素的测量值与标准值基本一致,测量值的标准偏差较小;测量20个空气滤膜实际样品,并与ICP-MS法作比对,大多数元素两种方法测量结果的相对偏差较小,测量值基本一致。     

Application of Non-Conventional Filtration Technologies in Pollution Control

Deep bed filtration is becoming increasing important in wastewater treatment particularly in tertiary treatment as stringent water quality standards are emphasized. A detailed pilot-scale filtration study conducted with secondary effluent in a sewage treatment plant indicated that tertiary filtration with prior alum flocculation is capable of producing high quality effluent, particularly an effluent with phosphorus content of less than 0.3 mg/L (Vigneswaran and Ngo, 1994). Main problem of dual media filter has been rapid headloss development thus frequent backwash requirement. To overcome this problem two independent experimental studies were conducted: one with mobile bed filtration (MBF) and the other with combined downflow floating medium flocculator/prefilter (DFF) and coarse sand filter (CSF) system. A semi-pilot scale mobile bed filtration study conducted using oxidation pond effluent indicated that MBF with contact-flocculation arrangement was good in removing COD, T-P and turbidity with practically no headloss development. Sand of 0.6-0.84 nm dia and 50 cm depth was sufficient to reduce the COD and P from 55 mg/L and 4.5 mg/L to 15 mg/L and 0.5 mg/L respectively at a filtration rate of 7.5 m3/m2.h. Another experimental study with combined DFF-CSF system indicated that the DFF with in-line flocculation addition is a good pretreatment unit to reduce the phosphate upto 80-90%. The fact that DFF resulted in uniform filterable-flocs, it can also successfully be used as a static flocculator/prefilter unit. The introduction of DFF on top of a coarse sand filter increased the filter run time and removal efficiency (more 90-95% of NH3-N and T-P removal respectively). Most importantly, the backwashing of this system was achieved with small quantity of water at low backwash indicated that the removal efficiency was also superior with this system apart from the major advantage of low operating cost.     

滤膜在颗粒物无机元素监测中的适用性研究

筛选国内外12个制造商的玻璃纤维、石英、特氟龙、聚丙烯、乙酸纤维、硝酸纤维和混合纤维等7类材质34种滤膜,测定滤膜中的铍、铬、锰、钴、镍、铜、锌、砷、钼、镉、锡、锑、铊和铅等14种元素含量,探讨不同材质滤膜中各元素的质量分数分布,采用大气固定源污染物排放标准中项目限值和分析方法标准中质量控制要求,对铜、锌之外的12种元素进行适用性评价。结果表明:玻璃纤维滤膜比其他材质滤膜中无机元素的质量分数高1～5个数量级,进口玻璃纤维滤膜中铬、镍、砷、镉等4种元素质量分数高于多数国产玻璃纤维滤膜,国产A、H玻璃纤维滤膜中14种元素质量分数相对较低;仅混合纤维滤膜中镉、铅的测定值浓度低于最严标准限值的10%,玻璃纤维滤膜之外的其他材质滤膜均能满足监测其余10种元素的本底需求。     

Systematic evaluation of dissolved lead sorption losses to particulate syringe filter materials

Distinguishing between soluble and particulate lead in drinking water is useful in understanding the mechanism of lead release and identifying remedial action. Typically, particulate lead is defined as the amount of lead removed by a 0.45-μm filter. Unfortunately, there is little guidance regarding selection of filter membrane material and little consideration to the possibility of the sorption of dissolved lead to the filter. The objective of this work was to examine the tendency of 0.45-μm syringe filter materials to adsorb lead. Tests were performed with water containing 40 and 24 μg/L soluble lead at pH 7 buffered with 50 mg C/L dissolved inorganic concentration (DIC). The amounts of lead sorbed greatly varied by filter, and only two filter types, polypropylene and mixed cellulose esters, performed well and are recommended. Great care must be taken in choosing a filter when filtering soluble lead and interpreting filter results.     

自制模拟样及留样复测的质控技术探讨

介绍了环境监测标准滤膜、标准滤筒、模拟降尘的制备方法、使用方法、实际效果。阐述了滤膜中铅、土壤样品、底泥（沉积物）、污水厂处理污泥等留样的来源、必要性及作用。探讨了滤膜中铅留样复测质控的评判依据。     

利用自动采样滤膜监测PM_(2.5)中铅和镉的可行性

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。     

Filtering effect of wind flow turbulence on atmospheric pollutant dispersion

This paper presents a model for coupling the statistics of wind velocity distribution and atmospheric pollutant dispersion. The effect of wind velocity distribution is modeled as a three-dimensional finite-impulse response (3D-FIR) filter. A phase space representation of the 3D-FIR filter window is discussed. The resulting pollutant dispersion is the multiplication in the phase space of the 3-D Fourier transform of the pollutant concentration and the volume described by the filter window coefficients. The shape of the filter window in the phase space enables representing such effects as vortex shedding thermal currents, etc. The impact of spatial distribution of the sensors on the resulting pollutant spatial distribution and the 3-D FIR filter model employed also discuss. The case of a neutrally buoyant plume emitted from an elevated point source in a turbulent boundary layer considers. The results show that wind turbulence is an important factor in the pollutant dispersion and introduces expected random fluctuations in pollutant distribution and leads to spreading the distribution due to wind mixing.     

Conditioning of Oily Sludge with Alum

Sludge dewatering is a process whereby water is removed from sludge so as to reduce its volume and alter its physical state from semisolid to damp solid. This physical change reduces the volume of sludge considerably and therefore the cost of disposal. The degree of reduction of sludge volume or dewatering is a function of the characteristics of sludge and the type of dewatering device. Sludge characteristics such as specific resistance, capillary suction time(CST), filter yield and solid content can be determined in the laboratories. Knowledge of these characteristics with different dosages of sludge conditioners helps in effective dewatering and sludge handling operations.Oil and grease have an affinity for suspended solids. Experiences show that the presence of oil in wastewater results in poor substrate utilization causing less aerobic treatment and subsequently hinder settling and dewatering processes. Sludge samples with different oil contents varying from 1.8% to 8.0% by weight have been examined in the laboratory to find out their specific resistance, capillary suction time and filter yield. Alum was used as a conditioner. Different dosages of alum varying from 2% to 12% by weight were used to determine the optimum chemical dosage for varying oil contents. Buchner funnel apparatus, filter leaf apparatus and capillary suction time test apparatus were used to determine the dewatering characteristics specific resistance, filter yield and capillary suction time respectively.Addition of alum decreases the specific resistances and capillary suction times of oily sludges rapidly upto 4% dosages. Alum dosages beyond 4% only increase the solids content in the sludge cake and increase the sludge volume to be handled. The total suspended solids of filtrate decrease with alum dosage. The correlations between dewatering characteristics were studied. A correlation between CST and specific resistance to filtration was established. CST can be measured easily and quickly in the laboratories. Using the CST and the correlation a quick prediction on dewaterability can be established.