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GB/T 13931-2017: Electrostatic precipitator -- Methods of performance tests
Status: Valid GB/T 13931: Evolution and historical versions
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Electrostatic precipitator -- Methods of performance tests
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| GB/T 13931-2002 | English | 639 |
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Methods of performance tests for electrostatic precipitators
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Basic data | Standard ID | GB/T 13931-2017 (GB/T13931-2017) | | Description (Translated English) | Electrostatic precipitator -- Methods of performance tests | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | J88 | | Classification of International Standard | 13.030.40 | | Word Count Estimation | 21,224 | | Date of Issue | 2017-05-12 | | Date of Implementation | 2017-12-01 | | Older Standard (superseded by this standard) | GB/T 13931-2002 | | Issuing agency(ies) | General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China | | Summary | This standard specifies the performance of the electrostatic precipitator test items, test methods and report preparation requirements. This standard applies to the performance test of electrostatic precipitator, wet electrostatic precipitator, electric bag composite dust collector can refer to the implementation. | GB/T 13931-2017: Electrostatic precipitator -- Methods of performance tests---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Electrostatic precipitator.Methods of performance tests
ICS 13.030.40
J88
National Standards of People's Republic of China
Replace GB/T 13931-2002
Electrostatic precipitator performance test method
Released on.2017-05-12
2017-12-01 implementation
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
China National Standardization Administration issued
Content
Foreword I
1 Scope 1
2 Terms and Definitions 1
3 Test item 1
4 Test Method 2
4.1 Dust removal efficiency test 2
4.2 Body Pressure Drop Test 9
4.3 Body Air Leakage Rate Test 9
4.4 Electrostatic precipitator power consumption test 10
4.5 Flue gas flow rate and smoke flow test 11
4.6 Flue gas moisture test 13
4.7 Flue gas temperature test 16
5 test report writing requirements 16
Appendix A (Normative) Water vapor pressure and moisture content when air is saturated at 101,325 Pa
Foreword
This standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB/T 13931-2002 "Test method for performance of electrostatic precipitators". Compared with GB/T 13931-2002, except editing
The main technical changes outside the sexual modification are as follows.
--- Revised the requirements of the filter device requirements (see 4.1.5, 4.1.4 of the.2002 version);
---Modified the filter cartridge preparation and sampling requirements (see 4.1.7,.2002 version of 4.1.6);
--- According to the integrity of the main technical indicators of product performance, the electric precipitator power consumption test (see 4.4).
This standard was proposed by the National Development and Reform Commission of the People's Republic of China.
This standard is under the jurisdiction of the National Environmental Protection Industry Standardization Technical Committee (SAC/TC275).
This standard was drafted. Zhejiang Feida Environmental Protection Technology Co., Ltd., Guodian Environmental Protection Research Institute, machinery industry environmental protection machinery products
Quality Supervision and Inspection Center, State Grid Zhejiang Electric Power Company Electric Power Research Institute.
The main drafters of this standard. Zhu Shaoping, Wu Quanming, Zhu Fahua, Yi Yuping, Yuan Weifeng, Zhou Xiaotong, Li Haitao, Zhou Xusheng, Zhao Jinda,
Chen Li, Zhong Jianfeng.
The previous versions of the standards replaced by this standard are.
---GB/T 13931-1992, GB/T 13931-2002.
Electrostatic precipitator performance test method
1 Scope
This standard specifies the test items, test methods and report preparation requirements for the performance of the electrostatic precipitator.
This standard is applicable to the performance test of electrostatic precipitators. The wet electrostatic precipitator and electric bag composite dust collector can be referred to for implementation.
2 Terms and definitions
The following terms and definitions apply to this document.
2.1
Standard state of gas standardizedstatusoffluegas
The gas state of the flue gas at a temperature of 273 K and an atmospheric pressure of 101,325 Pa, referred to as "standard state".
Note. The concentration of atmospheric pollutants specified in this standard refers to the value of dry flue gas under standard conditions.
2.2
Constant velocity sampling isokineticsampling
The sampling method of the velocity of the dust-containing gas entering the sampling nozzle is equal to the velocity of the dust-containing gas at the sampling point on the cross section of the flue.
2.3
Equivalent diameter equivalentdiameter
The diameter of the flue when the flue is a circular pipe; when the flue is a rectangular pipe, it is equal to twice the product of length and width divided by the sum of length and width (unit. m).
2.4
Internal sampling internalsampling
Place the sample nozzle and filter in the flue for direct sampling.
2.5
Multi-point moving sampling method multi-pointsmovingsampling
A sampling method in which sampling is performed at each determined sampling point by the same sampling device, and the sampling time of each point is equal.
2.6
Flue gas moisture content fluegashumidity
The amount of water vapor in the flue gas coexisting with 1kg of dry flue gas.
2.7
Electric precipitator power consumption powerconsumptionofelectrostaticprecipitator
The total active power (unit. kW) consumed by the ESP high and low voltage power supply unit per unit time.
3 test items
Test items include.
a) dust removal efficiency test;
b) body pressure drop test;
c) body air leakage rate test;
d) Electrostatic precipitator power consumption test.
4 test methods
4.1 Dust removal efficiency test
4.1.1 Overview
At the same time, the dust concentration of the flue gas at the inlet and outlet of the electrostatic precipitator and the air leakage rate of the main body of the electrostatic precipitator are tested, and the dust removal efficiency is obtained through calculation.
4.1.2 Provisions for sampling position, sampling hole and sampling point
4.1.2.1 Sampling position
The sampling position should be selected in the straight pipe section where the airflow is stable, and other interference sources such as elbows and reducers are more than 6 times equivalent diameter in the downstream direction.
The upstream direction is greater than 3 equivalents in diameter. When selecting a position, the vertical pipe section should be given priority. When the length of the flue cannot meet the above requirements, it can be rooted.
According to the actual situation, a relatively suitable pipe segment is selected as the sampling position.
4.1.2.2 Sampling hole
The size of the sampling hole should be sufficient to insert the largest sampling device into the flue. The short tube of the orifice should not be too long, and the structure of the sampling hole can be determined by itself.
4.1.2.3 Number of sampling points
4.1.2.3.1 Circular flue
On the selected test section, set two sampling holes perpendicular to each other, and then divide the flue section into a certain number of concentric circles.
Ring, through the sampling hole along the diameter direction of the section, take 4 points on each of the equal area rings as sampling points, as shown in Figure 1.
Figure 1 Circular flue sampling point
The number of sampling points is determined according to Table 1.
Table 1 Circular ring and other area ring and sampling points
Flue diameter/m number of sampling points (total of two holes)
D≤1
1 \u003cd≤2
2 \u003cd≤3
3 \u003cd≤5
5 \u003cd≤7
1~2
2~3
3~4
4~5
5~6
4~8
8~12
12~16
16~20
20~24
Note. When the diameter d of the flue exceeds 7m, it is calculated as not less than 4m2 per ring area.
The distance between each sampling point from the center of the flue is calculated according to formula (1).
Ri=R×
2i-1
2n
(1)
In the formula.
Ri --- the distance of the sampling point from the center of the flue, in meters (m);
R --- flue radius, in meters (m);
i --- the sequence number of the sampling point from the center of the flue;
n --- The number of rings divided.
The position of the sampling point can be expressed by the distance of the sampling point from the inner wall of the flue. See the multiple of the diameter of the flue from the inlet end of the sampling hole to each sampling point.
Table 2.
Table 2 Flue diameter multiple of the sampling point from the inner wall of the flue
Sampling point number
Ring number
0.146
0.854
0.067
0.250
0.750
0.933
0.044
0.146
0.294
0.706
0.854
0.956
0.033
0.105
0.195
0.321
0.679
0.805
0.895
0.967
0.022
0.082
0.145
0.227
0.344
0.656
0.773
0.855
0.918
0.978
4.1.2.3.2 Rectangular flue
Divide the flue section into a number of small rectangles of equal area, so that the ratio of the adjacent sides of the small rectangle is close to 1, and the center of each small rectangle is
Samples, as shown in Figure 2.
Figure 2 Location of rectangular flue sampling points (N, n are the number of rows and columns of sampling points respectively)
The number of sampling points is determined according to Table 3.
Table 3 Rectangular flue sampling points
Flue stop area A/m2 equal area small rectangle number of sampling points
A≤1
1 \u003cA≤4
4 \u003cA≤9
9 \u003cA≤16
16 \u003cA≤20
20 \u003cA≤24
2×2
3×3
3×4
4×4
4×5
5×5
Note. When the flue cross-sectional area A is greater than 24m2, the length of the small rectangle is less than 1m.
4.1.3 Sampling method
Multi-point moving internal sampling.
4.1.4 Sampling method
4.1.4.1 Predictive flow rate method for constant velocity sampling
4.1.4.1.1 Test equipment. ordinary type smoke tester, ordinary type sampling tube.
4.1.4.1.2 Test method. pre-measure the flue gas flow rate at each sampling point in the flue, and then according to this flow rate and the selected sample nozzle diameter,
Calculate the sampling flow required for each point at constant speed, and then sample at each measurement point according to the calculated flow. See the forecasting flow rate sampling system
image 3.
Description.
1---flue; 7 --- regulating valve;
2---sampling tube; 8 --- pump;
3---condenser; 9 --- cumulative flow meter;
4---thermometer; 10---rotor flowmeter;
5---temperature gauge; 11---dryer.
6---vacuum pressure gauge;
Figure 3 Predictive flow rate sampling system
4.1.4.2 Dynamic pressure equalization method for constant velocity sampling
4.1.4.2.1 Test equipment. dynamic pressure balance type smoke tester, dynamic pressure balance type combination sampling tube.
4.1.4.2.2 Test method. By adjusting the sampling flow rate, the differential pressure reading of the orifice plate is equal to the gas dynamic pressure reading of the pitot tube, and the isokinetic sampling is achieved.
Sample requirements. The dynamic pressure balance sampling system is shown in Figure 4.
Description.
1---back-type pitot tube; 7 --- vacuum pressure gauge;
2---flue; 8 --- thermometer;
3---double micro-pressure gauge; 9 --- dryer;
4---exhaust pump; 10---condenser;
5---Rotor flowmeter; 11--- orifice plate;
6---cumulative flow meter; 12---sampling tube.
Figure 4 Dynamic pressure balance sampling system
4.1.4.3 Static pressure equalization method for constant velocity sampling
4.1.4.3.1 Test equipment. static pressure balance type smoke tester, static pressure balance type sampling tube.
4.1.4.3.2 Test method. By adjusting the sampling flow, the static pressure inside and outside the sampling tube is kept balanced to achieve the constant speed sampling requirement. Static pressure balance
The sampling system is shown in Figure 5.
Description.
1---flue; 6---rotor flowmeter;
2---sampling tube; 7---vacuum pressure gauge;
3---pressure deviation indicator; 8---temperature gauge;
4---exhaust pump; 9---dryer.
5---cumulative flow meter;
Figure 5 Static pressure balance sampling system
4.1.4.4 Pitot tube parallel velocity measurement
4.1.4.4.1 Test equipment. Pitot parallel smoke tester, multi-functional combination sampling tube.
4.1.4.4.2 Test method. Combine sampling tube, back-type pitot tube and thermocouple thermometer, according to the measured flow rate and other parameters
Value, adjust the sampling flow in time to ensure constant speed sampling conditions. The pitot tube parallel velocity sampling system is shown in Figure 6.
Description.
1---combination sampling tube; 6---rotor flowmeter;
2---flue; 7---vacuum pressure gauge;
3---micro pressure gauge; 8---temperature gauge;
4---exhaust pump; 9---dryer.
5---cumulative flow meter;
Figure 6 Pitot tube parallel velocity measurement sampling system
4.1.5 Filter device requirements
With the filter cartridge (membrane) method, the filter cartridge (film) requires that the capture rate for particles of 0.3 μm should be not less than 99.9%. Smoke temperature is lower than
At 300 ° C, the filter cartridge (membrane) material should be selected from quartz fiber and polytetrafluoroethylene. When it is higher than 300 °C, corundum is used.
4.1.6 Sampling calculation method
4.1.6.1 Calculation of sampling volume
The sampling volume is calculated according to formula (2).
Vsnd=0.0027Vm×
Pa pr
273 Tr
(2)
In the formula.
Vsnd---the sampling volume of dry flue gas under standard conditions, in liters (L);
Vm --- the sampling volume of dry flue gas under actual working conditions, the unit is liter (L);
Pa --- local atmospheric pressure, the unit is Pascal (Pa);
Pr --- the flue gas pressure before the flow meter, the unit is Pascal (Pa);
Tr --- Flue gas temperature before the flow meter, in degrees Celsius (°C).
4.1.6.2 Calculation of dust concentration of flue gas
The dust concentration of the flue gas is calculated according to formula (3) and formula (4).
c=
Vsnd×
103 (3)
In the formula.
c --- The dust concentration of dry flue gas under standard conditions, in milligrams per cubic meter (mg/m3);
m --- the amount of dust collected in milligrams (mg);
Vsnd---the sampling volume of dry flue gas under standard conditions, in liters (L).
m=m2-m1 (4)
In the formula.
m --- the amount of dust collected in milligrams (mg);
M2---The quality of the filter cartridge after sampling, in milligrams (mg);
M1---The mass of the filter cartridge before sampling, in milligrams (mg).
4.1.6.3 Calculation of dust removal efficiency
Dust removal efficiency is calculated by concentration method or gravimetric method.
a) The concentration method is calculated according to formula (5).
η=
Cin-cout(1 Δα)
Cin ×
100% (5)
In the formula.
η --- dust removal efficiency, expressed in %;
Cin---Dust concentration of imported flue gas (dry flue gas under standard conditions), the unit is milligrams per cubic meter (mg/m3);
Cout---Export flue gas dust concentration (dry flue gas under standard conditions), the unit is milligrams per cubic meter (mg/m3);
Δα---body air leakage rate, expressed in %.
b) The gravimetric method is calculated according to equation (6).
η=
Qmin-qmout
Qmin ×
100% (6)
In the formula.
η --- dust removal efficiency, expressed in %;
Qmin --- Total mass flow of imported soot, in kilograms per hour (kg/h);
Qmout---Total mass flow of export fumes, in kilograms per hour (kg/h).
4.1.7 Filter cartridge preparation and sampling requirements
Note the following points during filter cartridge preparation and sampling.
a) Filter cartridge preparation. put the qualified filter cartridges into the oven and bake at.200 °C for 1 h to eliminate the weight loss of the filter cartridge during high temperature sampling.
ring. After cooling, it is dried at a constant temperature of 105 ° C ~ 110 ° C for 2 h, placed in a special filter cylinder weighing bottle, placed in a desiccator
However, to room temperature, the mass m1 of the filter cartridge was weighed on a 0.01 mg balance and recorded. Repeat under constant temperature and humidity conditions
In the above operation, the weighing of the same filter cartridge is not more than 0.3mg twice, and two are reserved as the constant weight filter cartridge.
b) Record the temperature and humidity under constant temperature and humidity conditions, and ensure that the weighing conditions of the filter cartridge are consistent before and after sampling.
c) The sampling time depends on the dust particle concentration. For the low concentration test, the sampling time and flow rate are required to ensure that the final increment of the filter cartridge is not less than
2mg.
d) When sampling, the angle between the center line of the nozzle and the flue gas flow should be less than 5°.
e) Sampling shall be carried out simultaneously at the inlet and outlet of the electrostatic precipitator, and at least three valid tests shall be repeated under the same working conditions and averaged.
f) After the sampling is completed, put the sampled filter cartridge and two constant weight filter cartridges into the oven, bake at.200 ° C for 1 h, then cool and then
Dry at a constant temperature of 105 ° C ~ 110 ° C for 2 h, put it into a special filter cylinder weighing bottle, place it in a desiccator and cool to room temperature, then
The mass m2 of the filter cartridge was weighed on a 0.01 mg balance and recorded. Repeat the above operation under constant temperature and humidity conditions, the same
A filter cartridge is weighed twice to a difference of no more than 0.3 mg. The mass of the constant weight filter cartridge is different from the mass of the constant weight filter cartridge before the sampling.
Above 0.3 mg, the weighing result of the sampling filter cartridge is considered to be within the quality control range, and the result is reliable.
4.2 Body Pressure Drop Test
4.2.1 Test location
The test position should be as close as possible to the inlet and outlet of the electrostatic precipitator. Select a straight pipe section with an equivalent diameter of 1 inch from the inlet and outlet of the electrostatic precipitator.
on. If the objective conditions are not allowed, the efficiency hole test can also be used, but the pressure drop of some flue should be deducted from the test data.
4.2.2 Arrangement of measuring points and number of measuring points
Execute as specified in 4.1.2.
4.2.3 Test equipment
Pitot tube, micro pressure gauge, U-type pressure gauge.
4.2.4 Test method
Test the section on both sides of the inlet and outlet of the electrostatic precipitator and test the full pressure at each point, and measure the density of the atmosphere and the gas passing through the electrostatic precipitator.
Then calculate according to formula (7) and formula (8).
Δp=pin-pout pH (7)
In the formula.
Δp --- pressure drop in Pascal (Pa);
Pin --- the total pressure of the inlet section, the unit is Pascal (Pa);
Pout --- the average pressure of the exit section, in Pascal (Pa);
pH --- Correction of buoyancy of high temperature gas in Pascal (Pa).
pH=(ρa-ρ)gH (8)
In the formula.
pH --- correction value of high temperature gas buoyancy in Pascal (Pa);
Ρa --- atmospheric density in kilograms per cubic meter (kg/m3);
ρ --- the density of gas passing through the electrostatic precipitator in kilograms per cubic meter (kg/m3);
g --- gravitational acceleration in meters per square second (m/s2);
H --- Height difference of the entrance and exit test position, in meters (m).
4.3 Body air leakage rate test
4.3.1 Test location
Performed in accordance with 4.2.1.
4.3.2 Arrangement of measuring points and number of measuring points
Execute as specified in 4.1.2.
4.3.3 Test equipment
The electrochemical oxygen meter has an accuracy of not less than grade 1; a pitot tube and a micromanometer.
4.3.4 Test method
For the test of the air leakage rate of the main body, the following two methods are mainly used.
a) Using the oxygen balance method, that is, testing the oxygen content in the flue gas at the inlet and outlet sections of the electrostatic precipitator, and calculating by formula (9).
Δα=
O2out-O2in
21-O2out ×
100% (9)
In the formula.
Δα --- electric precipitator air leakage rate, expressed in %;
O2out---the average oxygen content of the flue gas at the exit section of the electrostatic precipitator, expressed in %;
O2in --- The average oxygen content of the flue gas in the inlet section of the electrostatic precipitator is expressed in %.
b) Test the pneumatic pressure of the inlet and outlet of the electrostatic precipitator, and find the flow of flue gas at both ends of the inlet and outlet, and then calculate by formula (10).
Δα=
Qvout-qvin
Qvin ×
100% (10)
In the formula.
Δα --- electric precipitator air leakage rate, expressed in %;
Qvout---The output of the standard dry smoke of the electrostatic precipitator, the unit is cubic meters per hour (m3/h);
Qvin --- Electrostatic precipitator imports the standard dry smoke volume, the unit is cubic meters per hour (m3/h).
4.4 Electrostatic precipitator power consumption test
4.4.1 Measurement method
4.4.1.1 Test equipment
Three-phase active energy meter.
4.4.1.2 Test method
Install the three-phase active energy meter at the dust removal and output bus of the electrostatic precipitator. According to the meter reading and measurement time before and after the measurement,
Calculate the power consumption P (unit. kW) of the electric precipitator, and calculate it according to formula (11).
P=
W2-W1
(11)
In the formula.
W2---Measure the reading of the electric energy meter in kilowatt-hours (kW·h);
W1---Measure the reading of the electric energy meter before the unit is kilowatt-hour (kW·h);
t --- Measurement time in hours (h).
There is any objection to the test results, whichever is the measurement method.
4.4.2 Calculation method
According to the primary current, voltage and power factor, meter reading, the power consumption of high and low voltage equipment (unit. kW) can be calculated.
The high pressure part is calculated according to formula (12) and formula (13).
Single phase (power frequency).
Phv=∑
i=1
(I1i×U1i×cosφ×10-3) (12)
Three-phase (high frequency).
Phv=∑
i=1
(3×I1i×U1i×cosφ×10-3)(13)
In the formula.
Phv --- power consumption of high voltage power supply equipment, in kilowatts (kW);
I1i --- primary current in amps (A);
U1i --- primary voltage in volts (V);
n --- number of electric fields;
Cosφ---power factor (0.7 for power frequency power supply and 0.9 for high frequency power supply).
The low-voltage rapping part is calculated according to formula (14).
Pr= 3×Ir×U3a×cosφ×10-3 (14)
In the formula.
Pr --- low-voltage rapping equipment power consumption, in kilowatts (kW);
Ir --- average current of low-voltage rapping equipment in ampere (A);
U3a --- three-phase average voltage in volts (V);
Cosφ---power factor (take 1).
The heating part is calculated according to formula (15).
Ph= 3×Ih×U3a×cosφ×10-3 (15)
In the formula.
Ph --- heating equipment power consumption, in kilowatts (kW);
Ih --- average current of low-voltage heating equipment in ampere (A);
U3a --- three-phase average voltage in volts (V);
Cosφ---power factor (take 1).
The electricity consumption of the electrostatic precipitator is calculated according to formula (16).
P=Phv Pr Ph (16)
In the formula.
P --- electric precipitator power consumption, the unit is kilowatts (kW);
Phv---Power consumption of high-voltage power supply equipment, in kilowatts (kW);
Pr --- low-voltage rapping equipment power consumption, in kilowatts (kW);
Ph --- Heating equipment power consumption, in kilowatts (kW).
4.5 Flue gas flow rate and smoke flow test
4.5.1 Test position and measuring point
Execute as specified in 4.1.2.
4.5.2 Test equipment
Pitot tube, tilt micromanometer or electronic micromanometer.
Pitot tube. it should be calibrated in the standard wind tunnel, the calibration coefficient can be measured before it can be used for measurement, and the standard pitot tube requires its calibration system.
The number is 1±0.01, and the back-type pitot tube requires a correction factor of 0.84±0.01.
Micro-pressure gauge. the accuracy of the tilting micro-pressure gauge should be no less than 2%, and the minimum graduation value should be no more than 2Pa, such as the fluctuation of the liquid column up and down during the test.
Large, the average value of the reading; the accuracy of the electronic micro-pressure gauge is not less than 1%, such as the micro-pressure gauge reading jumps larger during the test, the reading is flat
Mean.
4.5.3 Test method
Test the parameters of the pneumatic pressure, static pressure and temperature in the flue, calculate the flue gas flow rate, and calculate the flue gas volume. Test the smoke pneumatic pressure
The connection method is shown in Figure 7.
Description.
1---flue;
2---standard pitot tube;
3---inclined tube micromanometer;
4---back type pitot tube.
Figure 7 smoke pneumatic pressure test system
4.5.4 Calculation method
The average flow rate is calculated according to equations (17) and (18).
Us=0.0766Kp 273 ts× pd (17)
In the formula.
Us --- The average flow rate of smoke, in meters per second (m/s);
Kp --- pitot tube correction factor;
Ts --- flue gas temperature in degrees Celsius (°C);
Pd --- smoke pneumatic square root average, calculated according to formula (18).
Pd =
Pd1 pd2 pd3 pdn
(18)
In the formula.
Pd---the average value of the square root of the smoke pneumatic pressure;
Pdi --- measured value of dynamic pressure (i = 1, 2,, n) of each measuring point, the unit is Pascal (Pa);
n --- number of points.
The flue gas flow is calculated according to formula (19).
qVs=3600×us×A (19)
In the formula.
qVs---flue gas flow, the unit is cubic meters per hour (m
3/h);
Us --- The average flow rate of smoke, in meters per second (m/s);
A --- The cross-sectional area of the flue test station...
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