This standard is established in order to implement the national and local air pollutants emission standards and adjust the supervision of organized emission of stationary pollution source, especially collection method of sample.
The determination contents of particulates specified in this standard include sampling, determination and calculation. The supervision on stationary pollution source is generally implemented according to this standard, unless otherwise stated in relevant emission standard or analytical method standard, such as heat engine plant shall be according to emission standard; chromic (sulfur) acid mist, plumbum (or other metal) and its compounds shall be according to analytical method standard. Other provisions shall be complied with too. The emission monitoring of gaseous pollutants is complex. The sampling contents specified in this standard shall be regarded as general requirements. The sampling shall also comply with the specific provisions in emission standard and analytical method for gaseous pollutants standard.
This standard dose not relate to the requirements for operation condition and frequency of monitoring on the final acceptance of stationary pollution source and routine supervisory monitoring; the monitoring shall also be in accordance with relevant emission standard, monitoring regulations and provisions of the monitoring on the final acceptance of construction project by National Environmental Protection Agency.
Due to the requirements for monitoring conditions of boiler emission are specified not in the emission standard but in measuring method for smoke and dust, GB 5468-91 "Measuring Method for Smoke and Dust of Boiler Emission" is reserved even though this standard has been approved and issued. It must not be considered that this standard conflicts to it. The monitoring is carried out according to provisions, and this standard is cited for any unknown place. Added to this, GB 9078-88 "Determination of the Smoke and Dust of Industrial Kiln and Furnace" has been included in this standard.
GB 9078-88 "Determination of the Smoke and Dust of Industrial Kiln and Furnace" is abolished on the implementation date of this standard.
China Environmental Monitoring Central Station is responsible for the explanation of this standard.
This standard was proposed by the State Environment Protection Administration-Department of Science, Technology and Standards.
China Academy of Preventive Medicine, Institute of Environmental Health and sanitary Engineering is responsible for the draft of this standard.
Chief drafting staffs of this standard: Liu Guangshuan, Chang Dehua, Zhou Yangsheng, Zhou Guangfa and Liu Jiang.
1 Subject Content and Application Scope
1.1 This standard specifies the determination of particulates and sampling methods of gaseous pollutants emitted from exhaust gas of flue, chimney and exhaust funnel (hereinafter referred to as flue) and other stationary sources.
1.2 This standard is applicable to the determination of particulates and sampling of gaseous pollutants emitted from exhaust gas of boiler, industrial kiln, furnace and other stationary source.
1.3 In the determination of particulate concentration of exhaust gas from stationary sources, if the concentration is less than or equal to 20mg/m3, the gravimetric method in HJ 836 for the determination of low concentration particles in exhaust gas from stationary sources applies; but if it is larger than 20mg/m3 and does not exceed 50mg/m3, both this standard and HJ 836 apply. If the concentration determined according to this standard is less than or equal to 20mg/m3, the result shall be described as "< 20mg/m3".
2 Definitions
2.1 Particulates
Particulates refer to solid and liquid granular substance suspending in the emission gas generated by fuel and other substance during the process of burning, composition, decomposition as well as various materials in the mechanical processing.
2.2 Gaseous pollutants
Gaseous pollutants refer to various pollutants dispersed over the emission gas in gaseous state.
2.3 Dry exhaust gas at standard condition
Dry exhaust gas at standard condition refers to the moisture free exhaust gas when the temperature is 273 K and pressure is 101300 Pa.
3 Determination and Calculation Contents
3.1 Determination of exhaust parameters (temperature, pressure, moisture content and element).
3.2 Calculation of exhaust density and gas molecule.
3.3 Determination of exhaust flow rate and flow.
3.4 Determination of particulates in exhaust gas and calculation of emission concentration and emission rate.
3.5 Sampling of gaseous pollutants in exhaust gas and calculation of emission concentration and emission rate.
4 Basic Requirements of Sampling
4.1 Sampling condition
The sampling shall be carried out when the production equipments are at normal operation or at the specified operation condition according to the requirements of standards for the pollutants emission.
4.2 Sampling location and sampling point
4.2.1 Sampling location
4.2.1.1 Sampling location shall be prior selected at the vertical pipe section and turn aside flue elbow and cross-section position with rapid change. Sampling position shall be set no less than 6 times the diameter away from the downstream direction of the elbow, valve and reducer pipe and no less than 3 times the diameter away from the upstream direction of above parts. For rectangular flue, the equivalent diameter D = 2AB / (A + B), where A and B are side lengths.
4.2.1.2 For gaseous pollutants, the sampling location may not be restricted with above provisions due to the even mix, but it shall turn aside the vortex cavity. If simultaneously determinate the exhaust flow, the sampling location is selected according to 4.2.1.1.
4.2.1.3 Sampling location shall turn aside the locations that may danger the testing personnel.
4.2.2 Sampling hole
4.2.2.1 Open sampling hole on the selected determination position; the inner diameter of sampling hole shall not be less than 80mm; pipe range of sampling hole shall not be larger than 50mm. When it is out of service, it shall be blocked with cover plate, casing cap or pipe cap (Figure 1, Figure 2 and Figure 3). If the sampling hole is only used to sample gaseous pollutants, the inner diameter shall not be less than 40mm.
Figure 1 Sampling Hole with Cover Plate Figure 2 Sampling Hole with Casing Cap Figure 3 Sampling Hole with Pipe cap
(unit: mm) (unit: mm) (unit: mm)
4.2.2.2 The flue transport high temperature or toxic gas at positive pressure shall be adopted with sealed sampling hole with paddle valve (Figure 4).
Figure 4 Sealed Sampling Hole with Paddle Valve
4.2.2.3 For circular flue, the sampling hole shall be set on the orthogonal diameter lines containing the measuring points (Figure 5). For rectangular or square flue, the sampling hole shall be set on the extension line containing all the measuring points (Figure 6 and Figure 7).
Figure 6 Measuring Points of Rectangular Section Figure 7 Measuring Points of Square Section
4.2.3 Sampling platform
Sampling platform is set for sampling by testing personnel. It shall be with adequate working area to enable the worker to operate safely and conveniently. The area of platform shall not be less than 1.5m2 and set with 1.1m guard fence. The sampling hole is about 1.2~1.3m away from the platform surface.
4.2.4 Position and number of sampling points
4.2.4.1 Circular flue
a) Divide the flue into right quantity of concentric rings with equal-area; every measuring point shall be selected with the intersection point of the center line of each ring and the two vertical crossed diameter lines; one of the diameter lines shall be on the plane which is expected to have the maximum concentration change; If the measuring point is behind the elbow, the diameter line shall be on the A-A plane with elbow (Figure 8).
Figure 8 Measuring Points behind the Elbow on Circular Flue
b) For flue meeting 4.2.1.1. It may select the measuring points on only one of the diameter lines which are expected to the maximum concentration change.
c) For small flue with diameter less than 0.3m, uniform and symmetrical velocity distribution, and meets the requirements of 4.2.1.1, it may select the center of flue.
d) See Table 1 for the equal-area ring number, measuring diameter and measuring point number of circular flue with different diameter; measuring points shall not be less than 20 in principle.
Table 1 Determination of Ring and Measuring Point Number on Circular Flue
Flue diameter, m Equal-area ring number Measuring diameter number Measuring points number
<0.3
0.3~0.6
0.6~1.0
1.0~2.0
2.0~4.0
>4.0
1~2
2~3
3~4
4~5
5
1~2
1~2
1~2
1~2
1~2 1
2~8
4~12
6~16
8~20
10~20
c) See Figure 9 for the distance between measuring point and flue inwall, and the distance is determined according to Table 2. If the distance between measuring point and flue inwall is less than 25mm, take 25mm.
Figure 9 Distance Table of Sampling Point to Flue Inwall
Table 2 Distances between Measuring Point and Flue Inwall (Calculated by Flue Diameter D)
Measuring point number Ring number
1 2 3 4 5
1
2
3
4
5
6
7
8
9
10 0.146
0. 854 0.067
0.250
0.750
0.933 0.044
0.146
0.296
0.704
0.854
0.956 0.033
0.105
0.194
0.323
0.677
0.806
0.895
0.967 0.026
0.082
0.146
0.226
0.342
0.658
0.774
0.854
0.918
0.974
4.2.4.2 Rectangular or square flue
a) Divide flue section into right quantity of small block with equal-area; the center of each block is the measuring point. The number of small blocks is selected according to Table 3. The measuring point is less than 20 in principle.
Table 3 Block and Measuring Point Number on Rectangular (Square) Flue
Flue section area (m2) The long side length of equal-area small block (m) Total number of measuring points
<0.1 <0.32 1
0.1~0.5 <0.35 1~4
0.5~1.0 <0.50 4~6
1.0~4.0 <0.67 6~9
4.0~9.0 <0.75 9~16
>9.0 ≤1.0 ≤20
b) If the flue section area is less than 0.1m2, the velocity distribution is uniform and symmetrical and meets the requirements of 4.2.1.1; the cross-section center may be selected as measuring point.
4.2.4.3 If the flue arrangement cannot meet the requirements of 4.2.1.1, more sampling lines and measuring points shall be added.
5 Determination of Exhaust Parameters
5.1 Determination of exhaust temperature
5.1.1 Measuring position and measuring point
Generally it may be measured at the point near the flue center according to 4.2.1 and 4.2.4.
5.1.2 Instrument
a) Thermocouple or resistance thermometer: the indication error shall not be larger than ±3℃.
b) Mercury glass thermometer: the accuracy shall not be less than 2.5% , and the minimum division value shall not be larger than 2℃.
5.1.3 Determination process
a) Insert temperature measuring element into measuring point of flue, block the sampling hole and read after temperature stable.
b) When using mercury glass thermometer, the mercury glass thermometer can not be extracted from flue to read.
5.2 Determination of moisture content in exhaust gas
The moisture content in exhaust gas shall be determined with one of the methods of condensation method, dry/wet bulb method or weight method according to different measurement objects.
5.2.1 Sampling location and measuring point
Take sample on one measuring point near flue center according to 4.2.1 and 4.2.4.
5.2.2 Condensation method
5.2.2.1 Principle
Abstract a certain volume of exhaust gas from flue and pass it through condenser, calculate the moisture content in exhaust gas according to the condensing out water amount and saturated gas exhausted from condenser.
Foreword I
1 Subject Content and Application Scope
2 Definitions
3 Determination and Calculation Contents
4 Basic Requirements of Sampling
5 Determination of Exhaust Parameters
6 Calculations of Exhaust Density and Gas Molecular Weight
7 Determination of Exhaust Flow Rate and Flow
8 Determination of Particulates in Exhaust Gas
9 Sampling Method for Gaseous Pollutants
10 Calculation of Sampling Volume
11 Concentration and Emission Rate Calculation of Particulates or Gaseous Pollutants
12 Instrumental Correction
