1、December 2009DEUTSCHE NORM English price group 19No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 13.040.40!$ 2,0), the
2、 velocity at the nozzle edge is smaller than the velocity at the centre of the nozzle due to friction. c) Reynolds number The Reynolds number Re of the gas flow in the nozzle shall be in the region of laminar flow (100 2,5 m to 10,0 m aSeparation efficiency of ISO 7708:1995 at the corresponding part
3、icle diameter with a permissible deviation of 15 % Separation efficiency of ISO 7708:1995 at the corresponding particle diameter with a permissible deviation of 30 % aApproximate diameters. EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 12Table 2 Separation efficiency for the PM10impactor stage Part
4、icle diameter Separation efficiency for mono-disperse latex aerosol and greased collecting plates Separation efficiency for mono-disperse latex aerosol and quartz-fibre filters 2,0 m, to 10,0 m aSeparation efficiency of ISO 7708:1955 at the corresponding particle diameter with a permissible deviatio
5、n of 10 % Separation efficiency of ISO 7708:1995 at the corresponding particle diameter with a permissible deviation of 10 % 10,0 m to 20,0 m aSeparation efficiency of ISO 7708:1995 at the corresponding particle diameter with a permissible deviation of 15 % Separation efficiency of ISO 7708:1995 at
6、the corresponding particle diameter with a permissible deviation of 30 % aApproximate diameters. Key 1 high-risk respirable convention (PM2,5) A separation efficiency, in percent (%) 2 thoracic convention (PM10) d50cut-off diameter, in micrometres (m) Figure 3 Separation curves of PM10and PM2,5speci
7、fied in ISO 7708:1995 6.3 Verification of the separation curves The impactor shall be validated in order to prove that the performance criteria specified in 6.2 are met. The validation shall be carried out by a testing laboratory operating an internationally recognized quality-management system. NOT
8、E Requirements for testing laboratories are specified, for example, in ISO/IEC 17025. The separation efficiency shall be determined in accordance with the following procedure for each stage and the particle diameter ranges specified in Tables 1 and 2. The separation efficiency of the impactor stages
9、 shall be determined by performing two experiments for each stage with mono-disperse latex aerosols of different particle diameters. EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 13First, greased collecting plates are used to increase the adhesion and to reduce possible rebound of particles to eval
10、uate the optimum separation efficiency under laboratory conditions. Second, quartz-fibre filters (with the smooth surface towards the top) are used as collecting plates, as in the intended operation of the impactor. For the PM2,5stage, tests with at least six different particle diameters between 1 m
11、 and 10 m shall be performed. For the PM10stage, tests with at least six different particle diameters between 2 m and 20 m shall be performed. In both cases, the particle diameters shall be distributed over the full range about the cut-off diameter. One of these particle diameters shall be as close
12、as possible to the cut-off diameter. The resulting experimental separation efficiencies shall be compared with the reference curves specified in ISO 7708:1995 (see Figure 3). The deviations of the experimental separation efficiencies shall be within the permissible deviations specified in Tables 1 a
13、nd 2. The values of Stokess number St50for the 2,5 m and 10 m stages of the impactor under examination in relation to the cut-off diameter shall be calculated on the basis of the experimental data (see Annex B). The separation efficiencies and the values of Stokess number determined shall be reporte
14、d. 6.4 Operating conditions To meet the given cut-off limits of 10 m and 2,5 m particle diameters, the impactor shall be operated with a constant sample volumetric flow rate, to be previously determined. For a given impactor design, the volumetric flow rate depends only on the flue gas conditions an
15、d is calculated in accordance with Annex A. Isokinetic sampling should be established by selection of an appropriate sampling nozzle (see 8.3.4). If this is impossible, over-isokinetic sampling is preferred. Over-isokinetic sampling is preferred since the error in the collection efficiency is smalle
16、r than for sampling below isokinetic conditions (see 10.4). The measurement method specified in this International Standard is applicable for the operating conditions given in Table 3. Typical gas compositions range from air to flue gases with up to 30 % carbon dioxide. Table 3 Typical operating con
17、ditions of the measurement method Parameter Mean value Minimum value Maximum value Dust concentration in mg/m310 1 50 Temperature in C 135 20 250 Pressure in hPa 1 000 850 1 100 Humidity in g/m3 a30 0 100 aThe dew-point shall be below the flue gas temperature. If these operating conditions are not m
18、et, especially at a higher water-vapour content or higher flue gas temperatures, measures shall be taken so that the Reynolds number of each impactor stage is between 100 and 3 000. In this case, the similarity condition according to the theory of Marple (see Reference 11 in the Bibliography) is sti
19、ll fulfilled. The Reynolds number of the flow in each stage can be determined according to A.2.6. 6.5 Components The two-stage impactor shall have the following components: inlet cone in accordance with the requirements of ISO 12141, if needed; NOTE The corresponding requirements are identical to th
20、ose in EN 13284-1. EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 14 PM10nozzle plate; collecting plate for the particle fraction greater than 10 m; first diffuser, if needed; PM2,5nozzle plate; collecting plate for the particle fraction between 10 m and 2,5 m; second diffuser, if needed; backup fil
21、ter for the particle fraction smaller than 2,5 m. 7 Sampling train 7.1 Measuring setup Figure 4 shows an example of the general measurement setup. Key 1 entry nozzle 7 flowmeter 2 two-stage impactor 8 gas-volume measuring device with thermometer 3 suction tube 9 temperature measuring device 4 drying
22、 column 10 Pitot tube with differential pressure meter 5 manometer 11 gas flow in the flue gas duct 6 suction device Figure 4 Example of the design of the sampling system Measurements with an in-stack sampling system with a straight entry nozzle are recommended. EN ISO 23210:2009 (E) DIN EN ISO 2321
23、0:2009-12 15In-stack measurements with a goose-neck nozzle in front of the impactor can cause higher particle losses in the probe. Furthermore, out-stack measurements require an exact external thermal control of the impactor to meet the exact cut-off diameter. If in-stack measurements with a goose-n
24、eck nozzle in front of the impactor are performed, extensive validation experiments shall be performed, including the quantification of losses related to coarse and fine particles. These measurement setups shall only be used if losses of particles in the sampling train are below 10 % of the total ma
25、ss of fine particles collected on the collecting plate and backup filter. The requirements for components downstream of the impactor shall be in accordance with ISO 12141. NOTE The corresponding requirements are identical to those in EN 13284-1. 7.2 Equipment and working materials 7.2.1 Sampling equ
26、ipment The impactor shall be of corrosion-proof material, e.g. titanium or stainless steel. The entry nozzle shall be of the same material as the impactor. A set of nozzles with effective diameters between at least 6 mm and 18 mm shall be available (see Annex F). 7.2.2 Equipment for extraction and a
27、djustment of the sample volumetric flow rate The following equipment for extraction and adjustment of the sample volumetric flow rate shall be provided: bend downstream of the impactor of corrosion-proof material, if needed; suction tube downstream of the bend of corrosion-proof material with an app
28、ropriate internal diameter; for lengths over 2 m, a sufficiently stable supporting tube can be needed; gas-carrying flexible tubes of sufficient length for connecting the parts of the sampling train downstream of the suction tube; special heater for heating up the complete impactor, if needed; dryin
29、g tower with a desiccant for drying the sample gas; suction device (e.g. a corrosion-proof gastight pump with a protective filter and minimum delivery output of 4 m3/h at 400 hPa at the extraction side, preferably with automatic flow-control); gas volume meter of nominal capacity of 6 m3/h; gas flow
30、meter; temperature measuring device for the sample gas flow; pressure measuring device for static pressure in the duct or static differential pressure between the duct and the atmosphere at the measurement site; time measuring device; barometer for measuring the atmospheric pressure at the measureme
31、nt site; shut-off and control valves or other device for adjustment of the sample gas flow. Depending on the gas properties, a condensate trap can be necessary to avoid back-flow of condensate to the measuring filter. If necessary, heating or cooling of the condensate trap shall be provided. NOTE Re
32、quirements concerning the equipment for extraction and adjustment of the sample volumetric flow rate are specified, for example, in ISO 12141 and EN 13284-1. EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 167.2.3 Equipment for measuring the gas velocity, gas composition and reference quantities The
33、following equipment for measuring the gas velocity and the gas composition shall be provided: gas-velocity measuring device, e.g. Pitot tube with a micromanometer; gas analysers for determining CO2and O2in the flue gas; temperature measuring device; humidity measuring device. NOTE Requirements conce
34、rning the equipment for measuring the gas velocity and the gas composition are specified, for example, in ISO 12141 and EN 13284-1. 7.2.4 Equipment for pre-treatment and post-treatment in the laboratory The following equipment for the pre-treatment and post-treatment of the filter samples in the lab
35、oratory shall be provided: microbalance, e.g. measuring range: 60 g; resolution: 0,01 mg; drying chamber; transport container for the sampling plates and filters; punch for punching the plane filters, if needed. 7.2.5 Working materials The following working materials shall be provided: plane filter
36、of quartz-fibre material; drying agent, e.g. silica gel with colour indicator. The collecting plates and the backup filter shall consist of quartz-fibre plane filters, which shall comply with the following minimum requirements. a) The filter efficiency shall be better than 99,5 % on a test aerosol w
37、ith a mean particle diameter of 0,3 m at the maximum flow rate anticipated or 99,9 % on a test aerosol of 0,6 m mean diameter. This efficiency shall be certified by the filter supplier. b) The filter material shall not react with, or adsorb, gaseous compounds contained in the gas to be sampled and s
38、hall be thermally stable, taking into account the maximum temperature anticipated (conditioning, sampling, etc.). 8 Preparation, measurement procedure and post-treatment 8.1 General Measurement ports should be consistent with the requirements of International or National Standards with respect to th
39、e location, number and design. The dimensions of the measurement ports should allow straight insertion of the impactor into the flue gas duct without any contact with the inner duct walls. The measurement section shall be in accordance with the requirements of the applicable standard. NOTE Requireme
40、nts concerning the measurement section are specified, for example, in ISO 12141 or EN 15259. EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 17The flue gas conditions should be constant during sampling, to ensure that the isokinetic rate is kept between 90 % and 130 % of the calculated value (see 8.3
41、.4). The impactor shall be used in the flue gas duct with the entry nozzle in the upstream direction (see Figure 4). Sampling shall be performed at a sampling point representative of the flue gas velocity. This representative sampling point shall be determined in accordance with Annex G. It shall be
42、 guaranteed that the cut-off diameter does not change during sampling. Under constant flue gas conditions, this can be realized by a constant sample gas flow. An overall blank sample shall be taken as a quality control measure after each measurement series, or at least once a day without starting th
43、e suction device. This leads to an estimation of the dispersion of results related to the whole procedure, with a dust concentration close to zero, i.e. taking into account the contamination of filters during handling on site, and during transport, storage, handling in the laboratory and weighing. A
44、ll overall blank values shall be reported individually. 8.2 Pre-treatment 8.2.1 Impactor The impactor shall be cleaned in accordance with the manufacturers instructions and at a frequency specified in the measurement plan. NOTE Requirements concerning the measurement plan are specified, for example,
45、 in EN 15259. All internal surfaces of the impactor shall be cleaned between measurements on site, e.g. with a microfibre cloth. 8.2.2 Collecting plates and backup filters Preparation of filter sets shall be carried out in the laboratory. If needed, collecting plates (first and second impactor stage
46、) shall be punched with a concentric hole of an appropriate diameter suitable for the construction of the given impactor stage. After punching, check the punch edges visually and carefully remove loose fibres with a pair of tweezers. Collecting plates shall be used with the smooth surface towards th
47、e top. This International Standard recommends the use of non-greased quartz-fibre filters. However, the separation efficiency can be improved by the use of greased collecting plates. This requires additional validation in the field to take into account, for example, the influence of high temperature
48、s. Collecting plates and backup filters shall be placed in uniquely marked holders. Then the collecting plates and the backup filter with the holders shall be dried, equilibrated and weighed in accordance with ISO 12141. NOTE The corresponding requirements are identical to those in EN 13284-1. The c
49、ollecting plates and the backup filters shall be stored and transported in closed and clearly labelled boxes. 8.3 Measurement procedure 8.3.1 Measurement planning Measurement planning should generally include a) operating conditions of the plant, including fuel or feedstock, flue gas components and reference quantities (e.g. temperature, pressure, water-vapour content) to be measured, EN ISO 23210:2009 (E) DIN EN ISO 23210:2009-12 18b) sampling date and time and location of measurements, c)
