A system and method for measuring internal leakage in habitable area of ​​main control room of nuclear power plant

Abstract

The present invention belongs to the technical field of habitability testing and evaluation of important habitable areas of nuclear facilities, and specifically relates to a system and method for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant. The system for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant is used to measure the internal leakage of the habitable area of ​​the main control room of the nuclear power plant, including a tracer gas injection device for injecting tracer gas into the habitable area of ​​the main control room, and also including a tracer gas automatic sampling device for collecting and analyzing the tracer gas in the habitable area of ​​the main control room. The present invention can test the internal leakage of the habitable area of ​​the main control room of a nuclear power plant and evaluate the test results, providing a reference for the airtightness design of the habitable area of ​​the main control room under accident conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of habitability testing and evaluation of important habitable areas in nuclear power plants, and in particular relates to an internal leakage measurement system and method for a habitable area in a main control room of a nuclear power plant. Background Art

[0002] Important habitable areas of nuclear facilities refer to areas in nuclear facilities (such as nuclear power plants) that need to provide the necessary habitable atmospheric environment (air temperature, humidity, cleanliness, etc. meet the requirements for personnel residence) for on-duty personnel under abnormal conditions (nuclear leakage, biological and chemical attacks, etc.). Under abnormal conditions, staff on duty in important habitable areas can delay or terminate the development of abnormal conditions in nuclear facilities and reduce or eliminate the consequences of abnormal conditions. Therefore, important habitable areas are of great significance, especially the habitable area of ​​the main control room of a nuclear power plant, which is the key area among important habitable areas.

[0003] The air tightness test of the habitable area of ​​the main control room of a nuclear power plant is used to verify that the air tightness of the habitable area of ​​the main control room under accident conditions meets the design requirements. The specific technical indicator is that the leakage in the habitable area of ​​the main control room (unpurified air enters the habitable area of ​​the main control room through the pressure boundary of the habitable area of ​​the main control room under accident conditions) meets the design requirements. The tracer gas method is used to test the leakage in the habitable area of ​​the main control room. The free volume of the habitable area of ​​the main control room is an important basic parameter. At present, the main control room habitable free volume test and test result evaluation method and the internal leakage test and test result evaluation method are still blank at home and abroad, and it is necessary to design a corresponding test plan to meet this demand. Summary of the invention

[0004] The purpose of the present invention is to provide a device and method for free volume test and test result evaluation and internal leakage test and test result evaluation of the habitable area of ​​the main control room of a nuclear power plant. The device and method can be directly applied to free volume test and test result evaluation and internal leakage test and test result evaluation of the habitable area of ​​the main control room of a nuclear power plant.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is a system for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant, which is used to measure the internal leakage of the habitable area of ​​the main control room of the nuclear power plant through the ventilation system of the habitable area of ​​the main control room, and includes a tracer gas injection device for injecting tracer gas into the habitable area of ​​the main control room, wherein the tracer gas includes high-purity sulfur hexafluoride gas and diluted sulfur hexafluoride gas, wherein the high-purity sulfur hexafluoride gas is sulfur hexafluoride gas with a mass fraction higher than 99.9%; the diluted sulfur hexafluoride gas is sulfur hexafluoride gas diluted in a ratio of 1:n, where n≥1; and also includes a tracer gas automatic sampling device for collecting and analyzing the tracer gas in the habitable area of ​​the main control room.

[0006] Furthermore, the tracer gas injection device includes a first pipeline with a first gas cylinder at the top and a tail end connected to the habitable area of ​​the main control room, the first gas cylinder is used to provide the high-purity sulfur hexafluoride gas; it also includes a first air blower connected to the first pipeline through a second pipeline, and a second air blower connected to the first pipeline through a third pipeline, the second pipeline is close to the top of the first pipeline, and the third pipeline is close to the tail end of the first pipeline; it also includes a gas flow meter arranged on the first pipeline between the second pipeline and the third pipeline; it also includes a sixth pipeline, one end of the sixth pipeline is connected to the first pipeline between the second pipeline and the gas flowmeter, and the other end is connected to the second gas cylinder, the second gas cylinder is used to provide the diluted sulfur hexafluoride gas; it also includes a third air blower connected to the sixth pipeline through a seventh pipeline.

[0007] Furthermore, the tracer gas injection device further comprises:

[0008] a second valve disposed on the second pipeline;

[0009] a fifth valve disposed on the third pipeline;

[0010] A first valve, a ninth valve and a fourth valve are arranged in series on the first pipeline between the second pipeline and the gas flow meter, the first valve is close to the second pipeline, the fourth valve is close to the gas flow meter; the ninth valve is located between the first valve and the fourth valve;

[0011] A seventh valve and an eighth valve are arranged in series on the sixth pipeline;

[0012] A sixth valve is provided on the seventh pipeline.

[0013] Furthermore, the tracer gas injection device further comprises:

[0014] A fourth pipeline having one end connected to the first pipeline, the fourth pipeline being connected to the first pipeline between the sixth pipeline and the fourth valve, and a third valve being provided on the fourth pipeline;

[0015] Also includes a fifth pipeline, one end of the fifth pipeline is connected to the first valve, and the other end is connected to the first pipeline between the first valve and the ninth valve;

[0016] It also includes an eighth pipeline, one end of which is connected to the seventh valve, and the other end of which is connected to the sixth pipeline between the seventh valve and the eighth valve;

[0017] The first valve and the seventh valve are pressure reducing valves, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve and the ninth valve are manual valves; and the eighth valve is an injection pipeline switching valve.

[0018] further,

[0019] The tracer gas automatic sampling device comprises a plurality of sampling pipelines, the top ends of the sampling pipelines are connected to the sampling points in the habitable area of ​​the main control room, the tail ends of the sampling pipelines are connected to a gas sampling bag, and each of the sampling pipelines is provided with a sampling pump and a solenoid valve;

[0020] There are 40 sampling pipelines, including a first sampling pipeline, a second sampling pipeline and a third sampling pipeline;

[0021] A first sampling pump and a first solenoid valve are provided on the first sampling pipeline;

[0022] A second sampling pump and a second solenoid valve are provided on the second sampling pipeline;

[0023] The third sampling pipeline is provided with a third sampling pump and a third solenoid valve.

[0024] Furthermore, the sampling pump and the solenoid valve on the sampling pipeline are connected to the tracer gas concentration analysis device, and are controlled by the automatic control program in the tracer gas concentration analysis device to achieve automatic control start and stop; the tracer gas concentration analysis device provides two control modes of "air volume measurement sampling" and "other measurement sampling", and the air volume measurement sampling uses the first sampling pipeline, the second sampling pipeline and the third sampling pipeline.

[0025] further,

[0026] The main control room habitable area ventilation system includes a normal return air chamber, a normal supply air chamber, a normal fresh air chamber, an emergency return air chamber and an emergency supply air chamber;

[0027] The normal return air chamber is connected to one end of the habitable area of ​​the main control room through a first ventilation line, and the normal supply air chamber is connected to the other end of the habitable area of ​​the main control room through a second ventilation line; the normal return air chamber and the normal supply air chamber are connected through a third ventilation line and a fourth ventilation line, a first normal fan is provided on the third ventilation line, and a second normal fan is provided on the fourth ventilation line; and also includes a fifth ventilation line, one end of the fifth ventilation line is connected to the normal fresh air chamber, and the other end is divided into two paths, one path is connected to the third ventilation line between the normal return air chamber and the first normal fan through a sixth ventilation line, and the other path is connected to the fourth ventilation line between the normal return air chamber and the second normal fan through a seventh ventilation line;

[0028] The emergency return air chamber and the emergency supply air chamber are connected via the tenth ventilation pipeline and the eleventh ventilation pipeline; a first iodine adsorber and a first emergency blower are arranged in series on the tenth ventilation pipeline, wherein the first iodine adsorber is close to the emergency return air chamber; a second iodine adsorber and a second emergency blower are arranged in series on the eleventh ventilation pipeline, wherein the second iodine adsorber is close to the emergency return air chamber;

[0029] The emergency return air chamber is also connected to the first ventilation pipeline via an eighth ventilation pipeline, and the emergency air supply chamber is also connected to the normal return air chamber via a fifteenth ventilation pipeline;

[0030] The emergency return air chamber is also connected to the first emergency fresh air outlet via a twelfth ventilation pipeline, and connected to the second emergency fresh air outlet via a thirteenth ventilation pipeline, and the twelfth ventilation pipeline and the thirteenth ventilation pipeline are connected via a fourteenth ventilation pipeline;

[0031] A first ventilation valve is provided on the twelfth ventilation pipeline between the first emergency fresh air outlet and the fourteenth ventilation pipeline;

[0032] A second ventilation valve is provided on the thirteenth ventilation pipeline between the second emergency fresh air outlet and the fourteenth ventilation pipeline;

[0033] A third ventilation valve is provided on the eighth ventilation line;

[0034] It also includes a ninth ventilation pipeline provided with a fourth ventilation valve, wherein both ends of the ninth ventilation pipeline are connected to the eighth ventilation pipeline at both ends of the third ventilation valve;

[0035] A fifth ventilation valve and a sixth ventilation valve are arranged in series on the fifteenth ventilation pipeline, wherein the sixth ventilation valve is close to the normal return air chamber;

[0036] A seventh ventilation valve and an eighth ventilation valve are arranged in series on the first ventilation pipeline, wherein the seventh ventilation valve is close to the habitable area of ​​the main control room; the eighth ventilation pipeline is connected to the first ventilation pipeline between the seventh ventilation valve and the habitable area of ​​the main control room;

[0037] A ninth ventilation valve and a tenth ventilation valve are arranged in series on the fifth ventilation pipeline, wherein the ninth ventilation valve is close to the normal fresh air chamber;

[0038] The normal operating conditions of the ventilation system in the habitable area of ​​the main control room are as follows:

[0039] One of the first normal fan and the second normal fan is in operation, and the first emergency fan and the second emergency fan are out of operation;

[0040] The first ventilation valve, the second ventilation valve, the third ventilation valve, the fourth ventilation valve, the fifth ventilation valve and the sixth ventilation valve are in a closed state;

[0041] The seventh ventilation valve, the eighth ventilation valve, the ninth ventilation valve and the tenth ventilation valve are in an open state.

[0042] To achieve the above purpose, the present invention also discloses a method for measuring the amount of fresh air in the habitable area of ​​the main control room of a nuclear power plant, which adopts the internal leakage measurement system of the habitable area of ​​the main control room of the nuclear power plant as described above, and comprises the following steps:

[0043] Step S1, an injection point is set on the upstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline of the tracer gas injection device is connected to the injection point; a sampling point is set on the downstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room; the first sampling pipeline, the second sampling pipeline and the third sampling pipeline of the tracer gas automatic sampling device are connected to the sampling point;

[0044] Step S2, pipeline purging, opening the first valve, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve, the seventh valve, the eighth valve and the ninth valve, opening the first air purge device, the second air purge device and the third air purge device, and purging the first pipeline, the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min;

[0045] Step S3, closing the first valve, the second valve, the third valve, the fifth valve, the sixth valve, the seventh valve, the eighth valve and the ninth valve, and keeping the fourth valve open;

[0046] Step S4, setting the required tracer gas injection flow rate on the gas flow meter;

[0047] Step S5, opening the first gas cylinder and injecting the high-purity sulfur hexafluoride gas into the first pipeline;

[0048] Step S6, adjusting the first valve to a desired opening;

[0049] Step S7, after the tracer gas flow rate on the gas flow meter is stable, start the tracer gas automatic sampling device, the tracer gas injection flow rate is recorded as q, unit: ml / h; the first sampling pipeline, the second sampling pipeline and the third sampling pipeline are controlled by the automatic control program to start at the same start time, the start time is recorded as T0, and the sampling time is 5s;

[0050] Step S8: The three sampling concentrations of the first sampling line, the second sampling line and the third sampling line at the sampling point are C n1 , C n2 and C n3 , whose average value is C n , unit: ppm; when the C n1 , said C n2 and the C n3 Any one of the C n The deviation does not exceed 10%, then the fresh air volume Q used for measuring the internal leakage of the habitable area of ​​the main control room is n =q / C n , unit: m 3 / h;

[0051] Step S9, if the C n1 , said C n2 and the C n3 Any one of the C n If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest;

[0052] Step S10, injection ends;

[0053] Step S11, closing the first gas cylinder and the second gas cylinder;

[0054] Step S12, closing the fourth valve;

[0055] Step S13, opening the fifth valve;

[0056] Step S14, using the second air purger to purge the first pipeline for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0057] Step S15, closing the fifth valve;

[0058] Step S16, opening the third valve;

[0059] Step S17, using the first air purger to purge the first pipeline for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0060] Step S18, closing the third valve;

[0061] Step S19, closing the first valve.

[0062] Further, in step S1,

[0063] The injection point is selected upstream of the elbow or reducer of the upstream air duct;

[0064] The position of the upstream sampling point or the position of the downstream sampling point is selected on the long straight pipe section of the upstream air duct or the downstream air duct;

[0065] The distance between the position of the upstream sampling point or the position of the downstream sampling point and the position of the injection point is ≥5D; when the long straight pipe section is a circular pipe, D refers to the diameter of the long straight pipe section; when the long straight pipe section is a square pipe, D refers to the equivalent diameter of the long straight pipe section;

[0066] When the location of the upstream sampling point or the location of the downstream sampling point is a square tube, the ports of the three sampling lines are arranged equidistantly along a horizontal straight line at the center point of the cross section of the square tube;

[0067] When the location of the upstream sampling point or the location of the downstream sampling point is a circular tube, the ports of the three sampling lines are arranged at equal distances around the center point of the cross section of the circular tube.

[0068] To achieve the above purpose, the present invention also discloses a method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as described above, comprising the following steps:

[0069] Step S1, setting an injection point on the upstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room, and connecting the tail end of the first pipeline of the tracer gas injection device to the injection point; setting 40 sampling points in each room of the habitable area of ​​the main control room, and connecting the 40 sampling pipelines of the tracer gas automatic sampling device to the 40 sampling points one by one;

[0070] Step S2, pipeline purging, opening the first valve, the second valve, the third valve, the fourth valve and the fifth valve, opening the first air purge device and the second air purge device, and purging the first pipeline, the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min;

[0071] Step S3, closing the first valve, the second valve, the third valve and the fifth valve, and keeping the fourth valve open;

[0072] Step S4, setting the required tracer gas injection amount on the gas flow meter;

[0073] Step S5, adjusting the ventilation system of the habitable area of ​​the main control room to a normal operating condition;

[0074] Step S6, opening the first gas cylinder and injecting the sulfur hexafluoride gas into the first pipeline;

[0075] Step S7, adjusting the first valve to a desired opening;

[0076] Step S8, using the new method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as described above to test the air supply volume in the habitable area of ​​the main control room, denoted as Q s , unit: m 3 / h

[0077] Step S9, injection ends;

[0078] Step S10, the tracer gas injection amount is read by the gas flow meter and is recorded as Q2, unit: ml;

[0079] Step S11, closing the first gas cylinder;

[0080] Step S12, closing the fourth valve;

[0081] Step S13, opening the fifth valve;

[0082] Step S14, using the second air purger to purge the first pipeline for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0083] Step S15, closing the fifth valve;

[0084] Step S16, opening the third valve;

[0085] Step S17, using the first air purger to purge the first pipeline for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0086] Step S18, closing the third valve;

[0087] Step S19, closing the first valve;

[0088] Step S20: The designed volume of the habitable area of ​​the main control room is V d , unit: m 3 , after the set time, the tracer gas automatic sampling device is started to sample; the set time is V d / Q s , unit: h;

[0089] Step S21, the tracer gas concentration corresponding to the 40 sampling points is recorded as C vi , 1≤i≤40, unit: ppm, the average concentration of the 40 sampling points is C v , unit: ppm, each of the C vi With the C v The deviation does not exceed 10%, then the free volume of the habitable area of ​​the main control room V = Q s / C v , unit: m 3 ;

[0090] Step S22, if one of the C vi With the C v If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest.

[0091] To achieve the above purpose, the present invention also discloses a method for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as described above, which adopts a constant flow injection method and includes the following steps:

[0092] Step S1, a tracer gas injection point is respectively set on the twelfth ventilation pipeline and the thirteenth ventilation pipeline upstream of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline of the tracer gas injection device is divided into two paths connected to the two tracer gas injection points; 40 sampling points are set in each room of the habitable area of ​​the main control room, and the 40 sampling pipelines of the tracer gas automatic sampling device are connected to the 40 sampling points in a one-to-one correspondence; the background concentration of the 40 sampling points is measured;

[0093] Step S2, pipeline purging, opening the first valve, the second valve, the third valve, the fourth valve, the fifth valve, the sixth valve, the seventh valve, the eighth valve and the ninth valve, opening the first air purge device, the second air purge device and the third air purge device, and purging the first pipeline, the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min;

[0094] Step S3, closing the first valve, the second valve, the third valve, the fifth valve, the sixth valve, the seventh valve, the eighth valve and the ninth valve, and keeping the fourth valve open;

[0095] Step S4, setting the required tracer gas injection amount on the gas flow meter, denoted as q in , unit: ml / h;

[0096] Step S5, using the fresh air volume measurement method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as described above to measure the fresh air volume Qn in the habitable area of ​​the main control room, unit: m 3 / h;

[0097] Step S6, using the above-mentioned method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant to measure the free volume of the habitable area of ​​the main control room, denoted as V, unit: m 3 ;

[0098] Step S7, calculating the ventilation rate A=Qn / V of the habitable area of ​​the main control room;

[0099] Step S8, calculating the time T when the tracer gas in the habitable area of ​​the main control room reaches 95% of the final equilibrium concentration 95％ =3 / A;

[0100] Step S9, opening the first gas cylinder and injecting the high-purity sulfur hexafluoride gas into the first pipeline;

[0101] Step S10, adjusting the first valve to a desired opening;

[0102] Step S11, the injection flow rate of the first gas cylinder is q in1 , unit: ml / h, the continuous injection time of the high-purity sulfur hexafluoride gas T1=2 / A*n; the n represents the dilution multiple of the diluted sulfur hexafluoride gas;

[0103] Step S12, after the injection time T1 is reached, closing the first gas cylinder;

[0104] Step S13, using the first air purger to purge the first pipeline for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0105] Step S14, closing the first valve and the ninth valve;

[0106] Step S15, opening the second gas cylinder and injecting the diluted sulfur hexafluoride gas into the first pipeline;

[0107] Step S16, opening the eighth valve;

[0108] Step S17, adjusting the seventh valve to a desired opening;

[0109] Step S18, the injection flow rate of the second gas cylinder is q in2 , unit: ml / h, the continuous injection time of the diluted sulfur hexafluoride gas T2≥1 / A;

[0110] Step S19, when the tracer gas injection time reaches Tt=2 / A*n+1 / A, start the tracer gas sampling device to perform the first sampling on the 40 sampling points, and the tracer gas injection time is counted from the injection of the high-purity gas;

[0111] Step S20: In the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C 1i , 1≤i≤40, unit: ppm, the average concentration of the first tracer gas at the 40 sampling points is C1, unit: ppm, each C 1i The deviation from the stated C1 does not exceed 10%;

[0112] Step S21, a separate air volume measurement sampling point is set on the twelfth ventilation pipeline and the thirteenth ventilation pipeline upstream of the fan of the ventilation system in the habitable area of ​​the main control room, respectively, and the first sampling is performed at the two separate air volume measurement sampling points. The average value of the tracer gas concentration of the two separate air volume measurement sampling points is recorded as C b1 , unit: ppm, the C b1 The deviation from the stated C1 does not exceed 10%;

[0113] Step S22, after T hours, sampling the 40 sampling points for the second time; T≥0.25h;

[0114] Step S23, in the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C 2i , 1≤i≤40, unit: ppm, each of the C 2i The values ​​are all values ​​after deducting the background concentration; the average concentration of the second tracer gas at the 40 sampling points is C2, unit: ppm, each C 2i The deviation from the stated C2 does not exceed 10%;

[0115] Step S24, a second sampling is performed at the two separate air volume measurement sampling points, the tracer gas concentrations at the two separate air volume measurement sampling points are subtracted from the background concentration, and then the average value of the tracer gas concentrations at the two separate air volume measurement sampling points is calculated, which is recorded as C b2 , unit: ppm, the C b2 The deviation from the stated C2 does not exceed 10%;

[0116] Step S25, determine (C2-C1) / T<0.05*q in2 / V is established;

[0117] Step S26, if the inequality in step S25 holds, the test ends, and C2 is used as the final equilibrium concentration of the tracer gas in the habitable area of ​​the main control room of this test;

[0118] Step S27, the continuous injection direct test ends;

[0119] Step S28, closing the second gas cylinder;

[0120] Step S29, using the third air purger to purge the first pipeline, the purge time is 3-5 minutes, and the purge flow rate is 50-100 ml / min;

[0121] Step S30, closing the sixth valve, the seventh valve and the eighth valve;

[0122] Step S31, closing the fourth valve;

[0123] Step S32, opening the fifth valve;

[0124] Step S33, using the second air purger to purge the first pipeline, the purge time is 3-5 minutes, and the purge flow rate is 50-100 ml / min;

[0125] Step S34, closing the fifth valve;

[0126] Step S35,

[0127] If in step S20, any one of the C 1i Deviation from the stated C1 exceeds 10%;

[0128] Alternatively, in step S21, the C b1 Deviation from the stated C1 exceeds 10%;

[0129] Alternatively, in step S23, any one of the C 2i Deviation from said C2 exceeds 10%;

[0130] Alternatively, in step S24, the C b2 Deviation from said C2 exceeds 10%;

[0131] Alternatively, the inequality in step S25 does not hold;

[0132] Then it is necessary to find the cause, and after solving the problem, return to step S2 and retest;

[0133] Step S36, calculating the internal leakage of the habitable area of ​​the main control room: Q leak =q in2 / C2-Q n , unit: m3 / h;

[0134] Step S37, repeat the test n times, n≥1, calculate the internal leakage of the habitable area of ​​the main control room respectively, and take the average value as the final test result.

[0135] To achieve the above purpose, the present invention also discloses a measurement result evaluation method for the above-mentioned method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant, comprising the following steps:

[0136] Step S1, determining the resolution δ1 of the gas flow meter; unit: ml / h;

[0137] Step S2, determining the tracer gas injection flow rate q; unit: ml / h;

[0138] Step S3, calculating the uncertainty u(q) of the tracer gas injection flow rate q = 0.29δ1; unit: ml / min;

[0139] Step S4, determining the resolution δ2 of the tracer gas analyzer; unit: ppm;

[0140] Step S5, calculating the tracer gas concentration C at the air volume measurement point n =(C n1 +C n2 +C n3 ) / 3; unit: ppm;

[0141] Step S6, calculating the uncertainty of the tracer gas concentration u(C n )=0.167δ2; unit: ppm;

[0142] Step S7, using the fresh air volume measurement method as described above to calculate the fresh air volume Qn = q / C n ; Unit: m 3 / h;

[0143] Step S8, calculating the uncertainty of the fresh air volume, Unit: m 3 / h;

[0144] Step S9, in the jth test, in the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C j1i In the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C j2i ; 1≤j≤n, 1≤i≤40; unit: ppm;

[0145] Step S10, calculating the uncertainty u(C j1i )=u(Cj2i )=0.29δ2; unit: ppm;

[0146] Step S11, calculating the average concentration of the second tracer gas at the 40 sampling points of the second sampling of the jth test Unit: ppm;

[0147] Step S12, calculating the internal leakage Q of the jth test of the habitable area of ​​the main control room j , leak =q j , in / C j2 -Q n ; Unit: m 3 / h;q j，in It refers to the injection flow rate of diluted tracer gas in the jth test, ml / h;

[0148] Step S13, calculating the internal leakage of the habitable area of ​​the main control room Unit: m 3 / h;

[0149] Step S14, calculating the uncertainty of the leakage in the habitable area of ​​the main control room Unit: m 3 / h;

[0150] Step S15, calculating the uncertainty of n measurements of the internal leakage in the habitable area of ​​the main control room Unit: m 3 / h;

[0151] Step S16, determine the t corresponding to the t distribution when the degree of freedom is (n-1) 95％ value;

[0152] Step S17, calculate the comprehensive uncertainty of n measurements of the internal leakage in the habitable area of ​​the main control room: U(Q e,leak ) = t 95％ *u(Q e,leak ); Unit: m 3 / h;

[0153] Step S18, draw the conclusion: the internal leakage test result Q of the habitable area of ​​the main control room is e,leak , confidence interval [-U(Q e,leak ),U(Q e,leak )], confidence probability 95%; unit: m 3 / h.

[0154] The beneficial effect of the present invention is that the present invention can test the internal leakage of the habitable area of ​​the main control room of a nuclear power plant and evaluate the test results, providing a reference for the airtightness design of the habitable area of ​​the main control room under accident conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0155] Figure 1 is a schematic diagram of a ventilation system for a habitable area of ​​a main control room according to a specific embodiment of the present invention;

[0156] Figure 2 is a schematic diagram of a tracer gas injection device according to a specific embodiment of the present invention, the tracer gas injection device is arranged on the pipeline of the ventilation system of the habitable area of ​​the main control room, and also includes the first sampling pipeline to the third sampling pipeline of the tracer gas automatic sampling device;

[0157] Figure 3 is a schematic diagram of the automatic sampling device for tracer gas described in a specific embodiment of the present invention;

[0158] Figure 4 It is a diagram of the arrangement of sampling points inside the air duct described in a specific embodiment of the present invention;

[0159] Figure 5 It is a sampling point arrangement diagram of a habitable area of ​​a main control room of a nuclear power plant described in a specific embodiment of the present invention, indicating the positions of 40 sampling points for a measurement method for measuring leakage in the habitable area of ​​a main control room of a nuclear power plant using a constant flow injection method (the sampling points are used to connect with an automatic tracer gas sampling device);

[0160] Figure 6 is a schematic diagram of a ventilation system for a habitable area of ​​a main control room according to a specific embodiment of the present invention, in which the range of an internal leakage measurement test (see the dotted area) is indicated, and a tracer gas injection point 145 and a separate air volume measurement sampling point 146 for a measurement method for measuring internal leakage in a habitable area of ​​a main control room of a nuclear power plant are also indicated;

[0161] In the figure: 1-first gas cylinder, 2-second gas cylinder, 3-first air purge, 4-second air purge, 5-third air purge, 6-first valve, 7-second valve, 8-third valve, 9-fourth valve, 10-fifth valve, 11-sixth valve, 12-seventh valve, 13-eighth valve, 14-ninth valve, 15-gas flow meter, 16-first pipeline, 17-second pipeline, 18-third pipeline, 19-fourth pipeline, 20-fifth pipeline, 21-sixth pipeline, 22-seventh pipeline, 23-eighth pipeline, 24-first sampling pump, 25-second sampling pump, 26-third sampling pump, 27-fourth sampling pump, 28-fifth sampling pump, 29-sixth sampling pump, 30-seventh sampling pump pump, 31-eighth sampling pump, 32-ninth sampling pump, 33-tenth sampling pump, 34-eleventh sampling pump, 35-twelfth sampling pump, 36-thirteenth sampling pump, 37-fourteenth sampling pump, 38-fifteenth sampling pump, 39-sixteenth sampling pump, 40-seventeenth sampling pump, 41-eighteenth sampling pump, 42-nineteenth sampling pump, 43-twentieth sampling pump, 44-twenty-first sampling pump, 45-twenty-second sampling pump, 46-twenty-third sampling pump, 47-twenty-fourth sampling pump, 48-twenty-fifth sampling pump, 49-twenty-sixth sampling pump, 50-twenty-seventh sampling pump, 51-twenty-eighth sampling pump, 52-twenty-ninth sampling pump, 53-thirtieth sampling pump, 54-thirty-first sampling pump, 55-the thirty-second sampling pump, 56-the thirty-third sampling pump, 57-the thirty-fourth sampling pump, 58-the thirty-fifth sampling pump, 59-the thirty-sixth sampling pump, 60-the thirty-seventh sampling pump, 61-the thirty-eighth sampling pump, 62-the thirty-ninth sampling pump, 63-the fortieth sampling pump, 64-the first solenoid valve, 65-the second solenoid valve, 66-the third solenoid valve, 67-the fourth solenoid valve, 68-the fifth solenoid valve, 69-the sixth solenoid valve, 70-the seventh solenoid valve, 71-the eighth solenoid valve, 72-the ninth solenoid valve, 73-the tenth solenoid valve, 74-the eleventh solenoid valve, 75-the twelfth solenoid valve, 76-the thirteenth solenoid valve, 77-the fourteenth solenoid valve, 78-the fifteenth solenoid valve, 79-the sixteenth solenoid valve, 8 0-the seventeenth solenoid valve, 81-the eighteenth solenoid valve, 82-the nineteenth solenoid valve, 83-the twentieth solenoid valve, 84-the twenty-first solenoid valve, 85-the twenty-second solenoid valve, 86-the twenty-third solenoid valve, 87-the twenty-fourth solenoid valve, 88-the twenty-fifth solenoid valve, 89-the twenty-sixth solenoid valve, 90-the twenty-seventh solenoid valve, 91-the twenty-eighth solenoid valve, 92-the twenty-ninth solenoid valve, 93-the thirtieth solenoid valve, 94-the thirty-first solenoid valve, 95-the thirty-second solenoid valve, 96-the thirty-third solenoid valve, 97-the thirty-fourth solenoid valve, 98-the thirty-fifth solenoid valve, 99-the thirty-sixth solenoid valve, 100-the thirty-seventh solenoid valve, 101-the thirty-eighth solenoid valve, 102-the thirty-ninth solenoid valve,103-the 40th solenoid valve, 104-the tracer gas concentration analysis device, 105-the gas collection bag, 106-the habitable area of ​​the main control room, 107-the normal return air chamber, 108-the normal supply air chamber, 109-the normal fresh air chamber, 110-the emergency return air chamber, 111-the emergency supply air chamber, 112-the first ventilation pipeline, 113-the second ventilation pipeline, 114-the third ventilation pipeline, 115-the fourth ventilation pipeline, 116-the fifth ventilation pipeline, 117-the sixth ventilation pipeline, 118-the seventh ventilation pipeline, 119-the eighth ventilation pipeline, 120-the ninth ventilation pipeline, 121-the tenth ventilation pipeline, 122-the eleventh ventilation pipeline, 123-the twelfth ventilation pipeline, 124-the thirteenth ventilation pipeline, 1 25-the fourteenth ventilation pipeline, 126-the fifteenth ventilation pipeline, 127-the first normal fan, 128-the second normal fan, 129-the first emergency fan, 130-the second emergency fan, 131-the first iodine adsorber, 132-the second iodine adsorber, 133-the first emergency fresh air outlet, 134-the second emergency fresh air outlet, 135-the first ventilation valve, 136-the second ventilation valve, 137-the third ventilation valve, 138-the fourth ventilation valve, 139-the fifth ventilation valve, 140-the sixth ventilation valve, 141-the seventh ventilation valve, 142-the eighth ventilation valve, 143-the ninth ventilation valve, 144-the tenth ventilation valve, 145-the tracer gas injection point, 146-the individual air volume measurement sampling point. DETAILED DESCRIPTION

[0162] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0163] like Figure 1 As shown, the ventilation system of the habitable area of ​​the main control room of a nuclear power plant includes a normal return air chamber 107, a normal supply air chamber 108, a normal fresh air chamber 109, an emergency return air chamber 110 and an emergency supply air chamber 111;

[0164] The normal return air chamber 107 is connected to one end of the main control room habitable area 106 through the first ventilation pipeline 112, and the normal supply air chamber 108 is connected to the other end of the main control room habitable area 106 through the second ventilation pipeline 113; the normal return air chamber 107 and the normal supply air chamber 108 are connected through the third ventilation pipeline 114 and the fourth ventilation pipeline 115, the third ventilation pipeline 114 is provided with a first normal fan 127, and the fourth ventilation pipeline 115 is provided with a second normal fan 128; it also includes a fifth ventilation pipeline 116, one end of the fifth ventilation pipeline 116 is connected to the normal fresh air chamber 109, and the other end is divided into two paths, one path is connected to the third ventilation pipeline 114 between the normal return air chamber 107 and the first normal fan 127 through the sixth ventilation pipeline 117, and the other path is connected to the fourth ventilation pipeline 115 between the normal return air chamber 107 and the second normal fan 128 through the seventh ventilation pipeline 118;

[0165] The emergency return air chamber 110 and the emergency supply air chamber 111 are connected via the tenth ventilation pipeline 121 and the eleventh ventilation pipeline 122; the first iodine adsorber 131 and the first emergency fan 129 are arranged in series on the tenth ventilation pipeline 121, wherein the first iodine adsorber 131 is close to the emergency return air chamber 110; the second iodine adsorber 132 and the second emergency fan 130 are arranged in series on the eleventh ventilation pipeline 122, wherein the second iodine adsorber 132 is close to the emergency return air chamber 110;

[0166] The emergency return air chamber 110 is also connected to the first ventilation line 112 via the eighth ventilation line 119, and the emergency supply air chamber 111 is also connected to the normal return air chamber 107 via the fifteenth ventilation line 126;

[0167] The emergency return air chamber 110 is also connected to the first emergency fresh air outlet 133 through the twelfth ventilation pipeline 123, and connected to the second emergency fresh air outlet 134 through the thirteenth ventilation pipeline 124. The twelfth ventilation pipeline 123 and the thirteenth ventilation pipeline 124 are connected through the fourteenth ventilation pipeline 125;

[0168] A first ventilation valve 135 is provided on the twelfth ventilation line 123 between the first emergency fresh air outlet 133 and the fourteenth ventilation line 125;

[0169] A second ventilation valve 136 is provided on the thirteenth ventilation line 124 between the second emergency fresh air outlet 134 and the fourteenth ventilation line 125;

[0170] A third ventilation valve 137 is provided on the eighth ventilation line 119;

[0171] It also includes a ninth ventilation pipeline 120 provided with a fourth ventilation valve 138, and both ends of the ninth ventilation pipeline 120 are connected to the eighth ventilation pipeline 119 at both ends of the third ventilation valve 137;

[0172] A fifth ventilation valve 139 and a sixth ventilation valve 140 are arranged in series on the fifteenth ventilation pipeline 126, wherein the sixth ventilation valve 140 is close to the normal return air chamber 107;

[0173] A seventh ventilation valve 141 and an eighth ventilation valve 142 are arranged in series on the first ventilation pipeline 112, wherein the seventh ventilation valve 141 is close to the habitable area 106 of the main control room; the eighth ventilation pipeline 119 is connected to the first ventilation pipeline 112 between the seventh ventilation valve 141 and the habitable area 106 of the main control room;

[0174] A ninth ventilation valve 143 and a tenth ventilation valve 144 are arranged in series on the fifth ventilation pipeline 116 , wherein the ninth ventilation valve 143 is close to the normal fresh air chamber 109 .

[0175] The normal operating conditions of the ventilation system in the habitable area of ​​the main control room are as follows:

[0176] One of the first normal fan 127 and the second normal fan 128 is in operation, and the first emergency fan 129 and the second emergency fan 130 are out of operation;

[0177] The first ventilation valve 135, the second ventilation valve 136, the third ventilation valve 137, the fourth ventilation valve 138, the fifth ventilation valve 139 and the sixth ventilation valve 140 are in a closed state;

[0178] The seventh ventilation valve 141 , the eighth ventilation valve 142 , the ninth ventilation valve 143 and the tenth ventilation valve 144 are in an open state.

[0179] The main control room of a nuclear power plant can be occupied by the main control room, computer center, technical support center, safety office, study room, restaurant, locker room, toilet, corridor, morning meeting room, isolation office, duty room, etc. The sampling point arrangement is detailed in Figure 5 .

[0180] An internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant

[0181] like Figure 2As shown, the present invention provides a system for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant, which is used to measure the internal leakage of the habitable area 106 of the main control room of the nuclear power plant through the ventilation system of the habitable area of ​​the main control room, and includes a tracer gas injection device for injecting tracer gas into the habitable area 106 of the main control room, wherein the tracer gas includes high-purity sulfur hexafluoride gas and diluted sulfur hexafluoride gas, wherein the high-purity sulfur hexafluoride gas is sulfur hexafluoride gas with a mass fraction higher than 99.9%, and the diluted sulfur hexafluoride gas is sulfur hexafluoride gas diluted 1:n, where n≥1 (the specific dilution multiple is determined according to actual conditions); and also includes a tracer gas automatic sampling device for collecting and analyzing the tracer gas in the habitable area 106 of the main control room.

[0182] like Figure 2 As shown, the tracer gas injection device includes a first pipeline 16 with a first gas cylinder 1 at the top and a tail end connected to the habitable area 106 of the main control room, the first gas cylinder 1 is used to provide high-purity sulfur hexafluoride gas; it also includes a first air purge 3 connected to the first pipeline 16 through a second pipeline 17, and a second air purge 4 connected to the first pipeline 16 through a third pipeline 18, the second pipeline 17 is close to the top of the first pipeline 16, and the third pipeline 18 is close to the tail end of the first pipeline 16; it also includes a gas flow meter 15 arranged on the first pipeline 16 between the second pipeline 17 and the third pipeline 18, which is used to record the tracer gas injection amount; it also includes a sixth pipeline 21, one end of the sixth pipeline 21 is connected to the first pipeline 16 between the second pipeline 17 and the gas flow meter 15, and the other end is connected to the second gas cylinder 2, the second gas cylinder 2 is used to provide diluted sulfur hexafluoride gas; it also includes a third air purge 5 connected to the sixth pipeline 21 through a seventh pipeline 22.

[0183] The tracer gas injection device also includes:

[0184] A second valve 7 disposed on the second pipeline 17;

[0185] a fifth valve 10 disposed on the third pipeline 18;

[0186] The first valve 6, the ninth valve 14 and the fourth valve 9 are arranged in series on the first pipeline 16 between the second pipeline 17 and the gas flow meter 15, the first valve 6 is close to the second pipeline 17, the fourth valve 9 is close to the gas flow meter 15; the ninth valve 14 is located between the first valve 6 and the fourth valve 9;

[0187] A seventh valve 12 and an eighth valve 13 are arranged in series on the sixth pipeline 21;

[0188] The sixth valve 11 is arranged on the seventh pipeline 22 .

[0189] The tracer gas injection device also includes:

[0190] A fourth pipeline 19 having one end connected to the first pipeline 16, the fourth pipeline 19 being connected to the first pipeline 16 between the sixth pipeline 21 and the fourth valve 9, and the fourth pipeline 19 being provided with a third valve 8;

[0191] The fifth pipeline 20 is also included, one end of the fifth pipeline 20 is connected to the first valve 6, and the other end is connected to the first pipeline 16 between the first valve 6 and the ninth valve 14;

[0192] The eighth pipeline 23 is also included, one end of the eighth pipeline 23 is connected to the seventh valve 12, and the other end is connected to the sixth pipeline 21 between the seventh valve 12 and the eighth valve 13;

[0193] The first valve 6 and the seventh valve 12 are pressure reducing valves, the second valve 7, the third valve 8, the fourth valve 9, the fifth valve 10, the sixth valve 11 and the ninth valve 14 are manual valves; the eighth valve 13 is an injection pipeline switching valve.

[0194] like Figure 3 As shown, the tracer gas automatic sampling device includes a plurality of sampling pipelines, the top ends of the sampling pipelines are connected to the sampling points of the habitable area 106 of the main control room, the tail ends of the sampling pipelines are connected to a gas sampling bag 105, and a sampling pump and a solenoid valve are arranged on each sampling pipeline;

[0195] There are 40 sampling lines, including the first sampling line, the second sampling line and the third sampling line;

[0196] A first sampling pump 24 and a first solenoid valve 64 are provided on the first sampling pipeline;

[0197] A second sampling pump 25 and a second solenoid valve 65 are provided on the second sampling pipeline;

[0198] The third sampling pipeline is provided with a third sampling pump 26 and a third solenoid valve 66 .

[0199] The sampling pump and the solenoid valve on the sampling pipeline are connected to the tracer gas concentration analysis device 104, and are controlled by the automatic control program in the tracer gas concentration analysis device 104 to realize automatic control start and stop; the tracer gas concentration analysis device 104 provides two control modes of "air volume measurement sampling" and "other measurement sampling", and the air volume measurement sampling uses the first sampling pipeline, the second sampling pipeline and the third sampling pipeline.

[0200] A fresh air volume measurement method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant

[0201] The present invention also discloses a method for measuring the amount of fresh air in the habitable area of ​​the main control room of a nuclear power plant, which adopts the internal leakage measurement system for the habitable area of ​​the main control room of the nuclear power plant as described above, and comprises the following steps:

[0202] Step S1, such as Figure 2 As shown, an injection point is set in the upstream air duct of the fan of the ventilation system in the habitable area of ​​the main control room, and the tail end of the first pipeline 16 of the tracer gas injection device is connected to the injection point; a sampling point ( Figure 6 145 is an injection point, 146 is a sampling point); the first sampling line, the second sampling line and the third sampling line of the tracer gas automatic sampling device are connected to the sampling point;

[0203] The injection point is selected at the upstream of the elbow or reducer of the upstream air duct;

[0204] The location of the upstream sampling point or the downstream sampling point is selected on the long straight pipe section of the upstream air duct or the downstream air duct;

[0205] The distance between the upstream sampling point or the downstream sampling point and the injection point is ≥5D; when the long straight pipe section is a circular pipe, D refers to the diameter of the long straight pipe section; when the long straight pipe section is a square pipe, D refers to the equivalent diameter of the long straight pipe section;

[0206] like Figure 4 As shown, when the location of the upstream sampling point or the location of the downstream sampling point is a square tube, the ports of the three sampling lines are arranged at equal distances along a horizontal straight line at the center point of the cross section of the square tube;

[0207] like Figure 4 As shown, when the location of the upstream sampling point or the location of the downstream sampling point is a circular tube, the ports of the three sampling lines are arranged around the center point of the cross section of the circular tube at equal distances;

[0208] Step S2, pipeline purging, open the first valve 6, the second valve 7, the third valve 8, the fourth valve 9, the fifth valve 10, the sixth valve 11, the seventh valve 12, the eighth valve 13 and the ninth valve 14, open the first air purge 3, the second air purge 4 and the third air purge 5, purge the first pipeline 16, the purge time is 5-10min, and the purge flow rate is 50-100ml / min;

[0209] Step S3, close the first valve 6, the second valve 7, the third valve 8, the fifth valve 10, the sixth valve 11, the seventh valve 12, the eighth valve 13 and the ninth valve 14, and keep the fourth valve 9 open;

[0210] Step S4, setting the required tracer gas injection flow rate on the gas flow meter 15;

[0211] Step S5, opening the first gas cylinder 1, and injecting high-purity sulfur hexafluoride gas into the first pipeline 16;

[0212] Step S6, adjusting the first valve 6 to a desired opening;

[0213] Step S7, after the tracer gas flow rate on the gas flow meter 15 is stable, start the tracer gas automatic sampling device, the tracer gas injection flow rate is recorded as q, unit: ml / h; the first sampling pipeline, the second sampling pipeline and the third sampling pipeline are controlled by the automatic control program to start at the same start time, the start time is recorded as T0, and the sampling time is 5s;

[0214] Step S8: The three sampling concentrations of the first sampling line, the second sampling line and the third sampling line at the sampling point are C n1 , C n2 and C n3 , whose average value is C n , unit: ppm; when C n1 , C n2 and C n3 Any one of C n If the deviation does not exceed 10%, the fresh air volume Q used for measuring the internal leakage of the habitable area 106 of the main control room is n =q / C n , unit: m 3 / h;

[0215] Step S9, if C n1 , C n2 and C n3 Any one of C n If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest;

[0216] Step S10, injection ends;

[0217] Step S11, closing the first gas cylinder 1 and the second gas cylinder 2;

[0218] Step S12, closing the fourth valve 9;

[0219] Step S13, opening the fifth valve 10;

[0220] Step S14, using the second air purge device 4 to purge the first pipeline 16 for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0221] Step S15, closing the fifth valve 10;

[0222] Step S16, opening the third valve 8;

[0223] Step S17, using the first air purge device 3 to purge the first pipeline 16 for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0224] Step S18, closing the third valve 8;

[0225] Step S19, closing the first valve 6.

[0226] A measurement method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant

[0227] The present invention also discloses a method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as described above, comprising the following steps:

[0228] Step S1, an injection point is set in the upstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline 16 of the tracer gas injection device is connected to the injection point; 40 sampling points are set in each room of the habitable area 106 of the main control room, and 40 sampling pipelines of the tracer gas automatic sampling device are connected to the 40 sampling points one by one;

[0229] Step S2, pipeline purging, open the first valve 6, the second valve 7, the third valve 8, the fourth valve 9 and the fifth valve 10, open the first air purge 3 and the second air purge 4, purge the first pipeline 16, the purge time is 5-10min, and the purge flow rate is 50-100ml / min;

[0230] Step S3, closing the first valve 6, the second valve 7, the third valve 8 and the fifth valve 10, and keeping the fourth valve 9 open;

[0231] Step S4, setting the required tracer gas injection amount on the gas flow meter 15;

[0232] Step S5, adjusting the ventilation system of the habitable area of ​​the main control room to a normal operating condition;

[0233] Step S6, opening the first gas cylinder 1, and injecting sulfur hexafluoride gas into the first pipeline 16;

[0234] Step S7, adjusting the first valve 6 to a desired opening;

[0235] Step S8, using the new method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as described above to test the air supply volume of the habitable area 106 of the main control room, denoted as Q s , unit: m 3 / h

[0236] Step S9, injection ends;

[0237] Step S10, the tracer gas injection amount is read by the gas flow meter 15, recorded as Q2, unit: ml;

[0238] Step S11, closing the first gas cylinder 1;

[0239] Step S12, closing the fourth valve 9;

[0240] Step S13, opening the fifth valve 10;

[0241] Step S14, using the second air purge device 4 to purge the first pipeline 16 for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0242] Step S15, closing the fifth valve 10;

[0243] Step S16, opening the third valve 8;

[0244] Step S17, using the first air purge device 3 to purge the first pipeline 16 for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0245] Step S18, closing the third valve 8;

[0246] Step S19, closing the first valve 6;

[0247] Step S20: The designed volume of the habitable area 106 of the main control room is V d , unit: m 3 , after the set time, start the tracer gas automatic sampling device to take samples; the set time is V d / Q s , unit: h;

[0248] Step S21, the tracer gas concentration corresponding to the 40 sampling points is recorded as C vi , 1≤i≤40, unit: ppm, the average concentration of 40 sampling points is C v , unit: ppm, each C vi With C v The deviation does not exceed 10%, then the free volume V of the habitable area 106 of the main control room is Q s / C v , unit: m 3 ;

[0249] Step S22, if a C vi With C v If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest.

[0250] A measurement method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant

[0251] The present invention also discloses a method for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as described above, which adopts a constant flow injection method and includes the following steps:

[0252] Step S1, such as Figure 6 As shown, a tracer gas injection point 145 is respectively set on the twelfth ventilation pipeline 123 and the thirteenth ventilation pipeline 124 upstream of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline 16 of the tracer gas injection device is divided into two paths connected to the two tracer gas injection points 145; 40 sampling points are set in each room of the habitable area 106 of the main control room, and 40 sampling pipelines of the tracer gas automatic sampling device are connected to the 40 sampling points one by one; the background concentration of the 40 sampling points is measured;

[0253] Step S2, pipeline purging, open the first valve 6, the second valve 7, the third valve 8, the fourth valve 9, the fifth valve 10, the sixth valve 11, the seventh valve 12, the eighth valve 13 and the ninth valve 14, open the first air purge 3, the second air purge 4 and the third air purge 5, purge the first pipeline 16, the purge time is 5-10min, and the purge flow rate is 50-100ml / min;

[0254] Step S3, close the first valve 6, the second valve 7, the third valve 8, the fifth valve 10, the sixth valve 11, the seventh valve 12, the eighth valve 13 and the ninth valve 14, and keep the fourth valve 9 open;

[0255] Step S4, setting the required tracer gas injection amount on the gas flow meter 15, denoted as q in , unit: ml / h;

[0256] Step S5, using the fresh air volume measurement method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as described above to measure the fresh air volume Qn of the habitable area 106 of the main control room, unit: m 3 / h;

[0257] Step S6, using the above-mentioned method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant to measure the free volume of the habitable area of ​​the main control room of the nuclear power plant, denoted as V, unit: m 3 ;

[0258] Step S7, calculating the ventilation rate A=Qn / V of the habitable area 106 of the main control room;

[0259] Step S8, calculating the time T when the tracer gas in the habitable area 106 of the main control room reaches the final equilibrium concentration of 95% 95％ =3 / A;

[0260] Step S9, opening the first gas cylinder 1, and injecting high-purity sulfur hexafluoride gas into the first pipeline 16;

[0261] Step S10, adjusting the first valve 6 to a desired opening;

[0262] Step S11, the injection flow rate of the first gas cylinder 1 is q in1 , unit: ml / h, continuous injection time of high-purity sulfur hexafluoride gas T1 = 2 / A*n; n represents the dilution multiple of the tracer gas of the diluted sulfur hexafluoride gas (for example, 20% tracer gas, then n = 5)

[0263] Step S12, after the injection time T1 is reached, the first gas cylinder 1 is closed;

[0264] Step S13, using the first air purge device 3 to purge the first pipeline 16 for 3-5 minutes, with a purge flow rate of 50-100 ml / min;

[0265] Step S14, closing the first valve 6 and the ninth valve 14;

[0266] Step S15, opening the second gas cylinder 2, and injecting diluted sulfur hexafluoride gas into the first pipeline 16;

[0267] Step S16, opening the eighth valve 13;

[0268] Step S17, adjusting the seventh valve 12 to a desired opening;

[0269] Step S18, the injection flow rate of the second gas cylinder 2 is q in2 , unit: ml / h, continuous injection time of diluted sulfur hexafluoride gas T2≥1 / A;

[0270] Step S19, when the tracer gas injection time reaches Tt=2 / A*n+1 / A, the tracer gas sampling device is started to perform the first sampling of 40 sampling points. The tracer gas injection time is counted from the injection of high-purity gas;

[0271] Step S20: In the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C 1i , 1≤i≤40, unit: ppm, the average concentration of the first tracer gas at the 40 sampling points is C1, unit: ppm, each C 1i The deviation from C1 does not exceed 10%;

[0272] Step S21, as Figure 6As shown, a separate air volume measurement sampling point 146 is set on the twelfth ventilation pipeline 123 and the thirteenth ventilation pipeline 124 upstream of the fan of the ventilation system in the habitable area of ​​the main control room, respectively. The first sampling is performed at the two separate air volume measurement sampling points 146, and the average value of the tracer gas concentration of the two separate air volume measurement sampling points 146 is recorded as C b1 , unit: ppm, C b1 The deviation from C1 does not exceed 10%;

[0273] Step S22, after T hours, sampling the 40 sampling points for the second time; T≥0.25h;

[0274] Step S23, in the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C 2i , 1≤i≤40, unit: ppm, each C 2i The values ​​are all after subtracting the background concentration; the average concentration of the second tracer gas at the 40 sampling points is C2, unit: ppm, each C 2i The deviation from C2 does not exceed 10%;

[0275] Step S24, a second sampling is performed at two separate air volume measurement sampling points 146, the tracer gas concentrations at the two separate air volume measurement sampling points 146 are subtracted from the background concentration, and then the average value of the tracer gas concentrations at the two separate air volume measurement sampling points 146 is calculated and recorded as C b2 , unit: ppm, C b2 The deviation from C2 does not exceed 10%;

[0276] Step S25, determine (C2-C1) / T<0.05*q in / V is established;

[0277] Step S26, if the inequality in step S25 holds, the test ends, and C2 is used as the final equilibrium concentration of the tracer gas in the habitable area of ​​the main control room of this test;

[0278] Step S27, the continuous injection direct test ends;

[0279] Step S28, closing the second gas cylinder 2;

[0280] Step S29, using the third air purge device 5 to purge the first pipeline 16, the purge time is 3-5 minutes, and the purge flow rate is 50-100 ml / min;

[0281] Step S30, closing the sixth valve 11, the seventh valve 12 and the eighth valve 13;

[0282] Step S31, closing the fourth valve 9;

[0283] Step S32, opening the fifth valve 10;

[0284] Step S33, using the second air purge device 4 to purge the first pipeline 16, the purge time is 3-5 minutes, and the purge flow rate is 50-100 ml / min;

[0285] Step S34, closing the fifth valve 10;

[0286] Step S35,

[0287] If in step S20, any C 1i Deviation from C1 exceeds 10%;

[0288] Alternatively, in step S21, C b1 Deviation from C1 exceeds 10%;

[0289] Alternatively, in step S23, any one C 2i Deviation from C2 exceeds 10%;

[0290] Alternatively, in step S24, C b2 Deviation from C2 exceeds 10%;

[0291] Or, the inequality in step S25 does not hold;

[0292] Then you need to find the cause, and after solving the problem, return to step S2 and test again;

[0293] Step S36, calculate the internal leakage of the habitable area 106 of the main control room: Q leak =q in2 / C2-Q n , unit: m 3 / h;

[0294] Step S37, repeat the test n times, n≥1, calculate the internal leakage of the habitable area 106 of the main control room respectively, and take the average value as the final test result.

[0295] A method for evaluating measurement results

[0296] The present invention also discloses a method for evaluating the measurement results of the above-mentioned method for measuring the leakage in the habitable area of ​​the main control room of a nuclear power plant, comprising the following steps:

[0297] Step S1, determining the resolution δ1 of the gas flow meter 15; unit: ml / h;

[0298] Step S2, determining the tracer gas injection flow rate q; unit: ml / h;

[0299] Step S3, calculating the uncertainty of the tracer gas injection flow rate q u(q) = 0.29δ1; unit: ml / min;

[0300] Step S4, determining the resolution δ2 of the tracer gas analyzer; unit: ppm;

[0301] Step S5, calculating the tracer gas concentration C at the air volume measurement point n =(C n1 +C n2 +C n3 ) / 3; Unit: ppm; (This "air volume measurement point" is the "sampling point" in step S8 of the air volume measurement method as described above)

[0302] Step S6, calculating the uncertainty of the tracer gas concentration u(C n )=0.167δ2; unit: ppm;

[0303] Step S7, using the fresh air volume measurement method as described above (the method in step S8) to calculate the fresh air volume Qn = q / C n ; Unit: m 3 / h;

[0304] Step S8, calculate the uncertainty of the fresh air volume, Unit: m 3 / h;

[0305] Step S9, in the jth test, in the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C j1i ; In the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C j2i ; 1≤j≤n, 1≤i≤40; unit: ppm;

[0306] Step S10, calculating the uncertainty u(C j1i )=u(C j2i )=0.29δ2; unit: ppm;

[0307] Step S11, calculate the average concentration of the second tracer gas at the 40 sampling points of the second sampling of the jth test Unit: ppm;

[0308] Step S12, calculating the internal leakage of the jth test of the habitable area 106 of the main control room

[0309] Q j , leak =q j，in / C j2 -Q n ; Unit: m 3 / h;q j，in Refers to the injection flow rate of diluted tracer gas (second gas cylinder 2) in the jth test, ml / h;

[0310] Step S13, calculating the internal leakage of the habitable area 106 of the main control room Unit: m 3 / h;

[0311] Step S14, calculating the uncertainty of the leakage in the habitable area 106 of the main control room Unit: m 3 / h;

[0312] Step S15, calculating the uncertainty of n measurements of the internal leakage of the habitable area 106 of the main control room Unit: m 3 / h;

[0313] Step S16, determine the t corresponding to the t distribution when the degree of freedom is (n-1) 95％ value;

[0314] Step S17, calculate the combined uncertainty of n measurements of the internal leakage of the habitable area 106 of the main control room: U(Q e,leak ) = t 95％ *u(Q e,leak ); Unit: m 3 / h;

[0315] Step S18, it is concluded that the internal leakage test result Q of the habitable area 106 of the main control room is e,leak , confidence interval [-U(Q e,leak ),U(Q e,leak )], confidence probability 95%; unit: m 3 / h.

[0316] The device described in the present invention is not limited to the embodiments described in the specific implementation manner. Those skilled in the art may derive other implementation manners based on the technical solution of the present invention, which also fall within the technical innovation scope of the present invention.

Claims

1. A system for measuring internal leakage in the habitable area of ​​a nuclear power plant main control room, characterized by: Used to measure the internal leakage of the habitable area (106) of the main control room of a nuclear power plant through the main control room habitable area ventilation system, comprising a tracer gas injection device for injecting tracer gas into the habitable area (106) of the main control room, wherein the tracer gas comprises high-purity sulfur hexafluoride gas and diluted sulfur hexafluoride gas, wherein the high-purity sulfur hexafluoride gas is sulfur hexafluoride gas with a mass fraction higher than 99.9%; the diluted sulfur hexafluoride gas is sulfur hexafluoride gas diluted in a ratio of 1:n, where n≥1; and also comprising a tracer gas automatic sampling device for collecting and analyzing the tracer gas in the habitable area (106) of the main control room; The main control room habitable area ventilation system comprises a normal return air chamber (107), a normal supply air chamber (108), a normal fresh air chamber (109), an emergency return air chamber (110) and an emergency supply air chamber (111); The normal return air chamber (107) is connected to one end of the main control room habitable area (106) via a first ventilation pipeline (112), and the normal supply air chamber (108) is connected to the other end of the main control room habitable area (106) via a second ventilation pipeline (113); the normal return air chamber (107) and the normal supply air chamber (108) are connected via a third ventilation pipeline (114) and a fourth ventilation pipeline (115), wherein the third ventilation pipeline (114) is provided with a first normal fan (127), and the fourth ventilation pipeline (115) is provided with a first normal fan (127). A second normal fan (128) is provided; and a fifth ventilation pipeline (116) is further provided, one end of the fifth ventilation pipeline (116) being connected to the normal fresh air chamber (109), and the other end being divided into two paths, one of which is connected to the third ventilation pipeline (114) between the normal return air chamber (107) and the first normal fan (127) through a sixth ventilation pipeline (117), and the other of which is connected to the fourth ventilation pipeline (115) between the normal return air chamber (107) and the second normal fan (128) through a seventh ventilation pipeline (118); The emergency return air chamber (110) and the emergency supply air chamber (111) are connected via a tenth ventilation pipeline (121) and an eleventh ventilation pipeline (122); a first iodine adsorber (131) and a first emergency fan (129) are arranged in series on the tenth ventilation pipeline (121), wherein the first iodine adsorber (131) is close to the emergency return air chamber (110); a second iodine adsorber (132) and a second emergency fan (130) are arranged in series on the eleventh ventilation pipeline (122), wherein the second iodine adsorber (132) is close to the emergency return air chamber (110); The emergency return air chamber (110) is also connected to the first ventilation pipeline (112) via an eighth ventilation pipeline (119), and the emergency air supply chamber (111) is also connected to the normal return air chamber (107) via a fifteenth ventilation pipeline (126); The emergency return air chamber (110) is also connected to the first emergency fresh air outlet (133) via a twelfth ventilation pipeline (123), and is connected to the second emergency fresh air outlet (134) via a thirteenth ventilation pipeline (124); the twelfth ventilation pipeline (123) and the thirteenth ventilation pipeline (124) are connected via a fourteenth ventilation pipeline (125); A first ventilation valve (135) is provided on the twelfth ventilation pipeline (123) between the first emergency fresh air outlet (133) and the fourteenth ventilation pipeline (125); A second ventilation valve (136) is provided on the thirteenth ventilation pipeline (124) between the second emergency fresh air outlet (134) and the fourteenth ventilation pipeline (125); A third ventilation valve (137) is provided on the eighth ventilation line (119); It also includes a ninth ventilation pipeline (120) provided with a fourth ventilation valve (138), and two ends of the ninth ventilation pipeline (120) are connected to the eighth ventilation pipeline (119) at two ends of the third ventilation valve (137); A fifth ventilation valve (139) and a sixth ventilation valve (140) are arranged in series on the fifteenth ventilation pipeline (126), wherein the sixth ventilation valve (140) is close to the normal return air chamber (107); A seventh ventilation valve (141) and an eighth ventilation valve (142) are arranged in series on the first ventilation pipeline (112), wherein the seventh ventilation valve (141) is close to the habitable area (106) of the main control room; the eighth ventilation pipeline (119) is connected to the first ventilation pipeline (112) between the seventh ventilation valve (141) and the habitable area (106) of the main control room; A ninth ventilation valve (143) and a tenth ventilation valve (144) are arranged in series on the fifth ventilation pipeline (116), wherein the ninth ventilation valve (143) is close to the normal fresh air chamber (109); The normal operating conditions of the ventilation system in the habitable area of ​​the main control room are as follows: One of the first normal fan (127) and the second normal fan (128) is in operation, and the first emergency fan (129) and the second emergency fan (130) are out of operation; The first ventilation valve (135), the second ventilation valve (136), the third ventilation valve (137), the fourth ventilation valve (138), the fifth ventilation valve (139) and the sixth ventilation valve (140) are in a closed state; The seventh ventilation valve (141), the eighth ventilation valve (142), the ninth ventilation valve (143) and the tenth ventilation valve (144) are in an open state.

2. The internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 1, characterized in that: The tracer gas injection device comprises a first pipeline (16) with a first gas cylinder (1) at the top and a tail end connected to the habitable area (106) of the main control room, wherein the first gas cylinder (1) is used to provide the high-purity sulfur hexafluoride gas; and further comprises a first air purge (3) connected to the first pipeline (16) via a second pipeline (17), and a second air purge (4) connected to the first pipeline (16) via a third pipeline (18), wherein the second pipeline (17) is close to the top of the first pipeline (16), and the third pipeline (18) is close to the first pipeline (16). ) at the tail end of the gas flow meter (15) disposed on the first pipeline (16) between the second pipeline (17) and the third pipeline (18); further comprising a sixth pipeline (21), one end of the sixth pipeline (21) being connected to the first pipeline (16) between the second pipeline (17) and the gas flow meter (15), and the other end being connected to a second gas cylinder (2), the second gas cylinder (2) being used to provide the diluted sulfur hexafluoride gas; and further comprising a third air purge (5) connected to the sixth pipeline (21) via a seventh pipeline (22).

3. The internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 2, characterized in that: The tracer gas injection device also includes: a second valve (7) disposed on the second pipeline (17); a fifth valve (10) disposed on the third pipeline (18); A first valve (6), a ninth valve (14) and a fourth valve (9) are arranged in series on the first pipeline (16) between the second pipeline (17) and the gas flow meter (15), wherein the first valve (6) is close to the second pipeline (17), and the fourth valve (9) is close to the gas flow meter (15); and the ninth valve (14) is located between the first valve (6) and the fourth valve (9); A seventh valve (12) and an eighth valve (13) are arranged in series on the sixth pipeline (21); A sixth valve (11) is arranged on the seventh pipeline (22).

4. The internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 3 is characterized in that: The tracer gas injection device also includes: a fourth pipeline (19) having one end connected to the first pipeline (16), the fourth pipeline (19) being connected to the first pipeline (16) between the sixth pipeline (21) and the fourth valve (9), and a third valve (8) being provided on the fourth pipeline (19); It also includes a fifth pipeline (20), one end of which is connected to the first valve (6), and the other end of which is connected to the first pipeline (16) between the first valve (6) and the ninth valve (14); It also includes an eighth pipeline (23), one end of the eighth pipeline (23) is connected to the seventh valve (12), and the other end is connected to the sixth pipeline (21) between the seventh valve (12) and the eighth valve (13); The first valve (6) and the seventh valve (12) are pressure reducing valves; the second valve (7), the third valve (8), the fourth valve (9), the fifth valve (10), the sixth valve (11) and the ninth valve (14) are manual valves; and the eighth valve (13) is an injection pipeline switching valve.

5. The internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 4, characterized in that: The tracer gas automatic sampling device comprises a plurality of sampling pipelines, the top ends of the sampling pipelines are connected to the sampling points of the habitable area (106) of the main control room, the tail ends of the sampling pipelines are connected to a gas sampling bag (105), and each of the sampling pipelines is provided with a sampling pump and a solenoid valve; There are 40 sampling pipelines, including a first sampling pipeline, a second sampling pipeline and a third sampling pipeline; The first sampling pipeline is provided with a first sampling pump (24) and a first solenoid valve (64); The second sampling pipeline is provided with a second sampling pump (25) and a second solenoid valve (65); The third sampling pipeline is provided with a third sampling pump (26) and a third solenoid valve (66).

6. The internal leakage measurement system for the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 5, characterized in that: The sampling pump and the electromagnetic valve on the sampling pipeline are both connected to a tracer gas concentration analysis device (104), and are controlled by an automatic control program in the tracer gas concentration analysis device (104) to achieve automatic control start and stop; the tracer gas concentration analysis device (104) provides two control modes, namely "air volume measurement sampling" and "other measurement sampling", and the air volume measurement sampling uses the first sampling pipeline, the second sampling pipeline and the third sampling pipeline.

7. A method for measuring the amount of fresh air in the habitable area of ​​a nuclear power plant main control room, using the internal leakage measurement system for the habitable area of ​​a nuclear power plant main control room as claimed in claim 6, comprising the following steps: Step S1, an injection point is set on the upstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline (16) of the tracer gas injection device is connected to the injection point; a sampling point is set on the downstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room; the first sampling pipeline, the second sampling pipeline and the third sampling pipeline of the tracer gas automatic sampling device are connected to the sampling point; Step S2, pipeline purging, opening the first valve (6), the second valve (7), the third valve (8), the fourth valve (9), the fifth valve (10), the sixth valve (11), the seventh valve (12), the eighth valve (13) and the ninth valve (14), opening the first air purge (3), the second air purge (4) and the third air purge (5), and purging the first pipeline (16), the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min; Step S3, closing the first valve (6), the second valve (7), the third valve (8), the fifth valve (10), the sixth valve (11), the seventh valve (12), the eighth valve (13) and the ninth valve (14), and keeping the fourth valve (9) open; Step S4, setting the required tracer gas injection flow rate on the gas flow meter (15); Step S5, opening the first gas cylinder (1) and injecting the high-purity sulfur hexafluoride gas into the first pipeline (16); Step S6, adjusting the first valve (6) to a desired opening; Step S7, after the tracer gas flow rate on the gas flow meter (15) is stable, start the tracer gas automatic sampling device, the tracer gas injection flow rate is recorded as q, unit: ml / h; the first sampling pipeline, the second sampling pipeline and the third sampling pipeline are controlled by the automatic control program to start at the same start time, the start time is recorded as T0, and the sampling time is 5s; Step S8: The three sampling concentrations of the first sampling line, the second sampling line and the third sampling line at the sampling point are C n1 , C n2 and C n3 , whose average value is C n , unit: ppm; when the C n1 , said C n2 and the C n3 Any one of the C n The deviation of is no more than 10%, then the fresh air volume Q used for measuring the internal leakage of the habitable area (106) of the main control room is n =q / C n , unit: m 3 / h; Step S9, if the C n1 , said C n2 and the C n3 Any one of the C n If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest; Step S10, injection ends; Step S11, closing the first gas cylinder (1) and the second gas cylinder (2); Step S12, closing the fourth valve (9); Step S13, opening the fifth valve (10); Step S14, using the second air purge device (4) to purge the first pipeline (16) for 3-5 minutes at a purge flow rate of 50-100 ml / min; Step S15, closing the fifth valve (10); Step S16, opening the third valve (8); Step S17, using the first air purge device (3) to purge the first pipeline (16) for 3-5 minutes, with a purge flow rate of 50-100 ml / min; Step S18, closing the third valve (8); Step S19, closing the first valve (6).

8. The method according to claim 7, characterized in that: exist In the step S1, The injection point is selected upstream of the elbow or reducer of the upstream air duct; The position of the upstream sampling point or the position of the downstream sampling point is selected on the long straight pipe section of the upstream air duct or the downstream air duct; The distance between the position of the upstream sampling point or the position of the downstream sampling point and the position of the injection point is ≥5D; when the long straight pipe section is a circular pipe, D refers to the diameter of the long straight pipe section; when the long straight pipe section is a square pipe, D refers to the equivalent diameter of the long straight pipe section; When the location of the upstream sampling point or the location of the downstream sampling point is a square tube, the ports of the three sampling lines are arranged equidistantly along a horizontal straight line at the center point of the cross section of the square tube; When the location of the upstream sampling point or the location of the downstream sampling point is a circular tube, the ports of the three sampling lines are arranged at equal distances around the center point of the cross section of the circular tube.

9. A method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 6, comprising the following steps: Step S1, setting an injection point in the upstream air duct of the fan of the ventilation system of the habitable area of ​​the main control room, and connecting the tail end of the first pipeline (16) of the tracer gas injection device to the injection point; setting 40 sampling points in each room of the habitable area (106) of the main control room, and connecting the 40 sampling pipelines of the tracer gas automatic sampling device to the 40 sampling points in a one-to-one correspondence; Step S2, pipeline purging, opening the first valve (6), the second valve (7), the third valve (8), the fourth valve (9) and the fifth valve (10), opening the first air purge (3) and the second air purge (4), and purging the first pipeline (16), the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min; Step S3, closing the first valve (6), the second valve (7), the third valve (8) and the fifth valve (10), and keeping the fourth valve (9) open; Step S4, setting the required tracer gas injection amount on the gas flow meter (15); Step S5, adjusting the ventilation system of the habitable area of ​​the main control room to a normal operating condition; Step S6, opening the first gas cylinder (1) and injecting the sulfur hexafluoride gas into the first pipeline (16); Step S7, adjusting the first valve (6) to a desired opening; Step S8, using the new method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 8 to test the air supply volume of the habitable area (106) of the main control room, denoted as Q s , unit: m 3 / h Step S9, injection ends; Step S10, the tracer gas injection amount is read by the gas flow meter (15), recorded as Q2, unit: ml; Step S11, closing the first gas cylinder (1); Step S12, closing the fourth valve (9); Step S13, opening the fifth valve (10); Step S14, using the second air purge device (4) to purge the first pipeline (16) for 3-5 minutes at a purge flow rate of 50-100 ml / min; Step S15, closing the fifth valve (10); Step S16, opening the third valve (8); Step S17, using the first air purge device (3) to purge the first pipeline (16) for 3-5 minutes, with a purge flow rate of 50-100 ml / min; Step S18, closing the third valve (8); Step S19, closing the first valve (6); Step S20, the design volume of the habitable area (106) of the main control room is V d , unit: m 3 , after the set time, the tracer gas automatic sampling device is started to sample; the set time is V d / Q s , unit: h; Step S21, the tracer gas concentration corresponding to the 40 sampling points is recorded as C vi , 1≤i≤40, unit: ppm, the average concentration of the 40 sampling points is C v , unit: ppm, each of the C vi With the C v The deviation of does not exceed 10%, then the free volume V of the habitable area (106) of the main control room is Q s / C v , unit: m 3 ; Step S22, if one of the C vi With the C v If the deviation exceeds 10%, it is necessary to find the cause. After solving the problem, return to step S2 and retest.

10. A method for measuring the internal leakage of the habitable area of ​​the main control room of a nuclear power plant using the internal leakage measurement system of the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 6, using a constant flow injection method, comprising the following steps: Step S1, a tracer gas injection point (145) is respectively provided on the twelfth ventilation pipeline (123) and the thirteenth ventilation pipeline (124) upstream of the fan of the ventilation system of the habitable area of ​​the main control room, and the tail end of the first pipeline (16) of the tracer gas injection device is divided into two paths connected to the two tracer gas injection points (145); 40 sampling points are provided in each room of the habitable area (106) of the main control room, and the 40 sampling pipelines of the tracer gas automatic sampling device are connected to the 40 sampling points in a one-to-one correspondence; and the background concentration of the 40 sampling points is measured; Step S2, pipeline purging, opening the first valve (6), the second valve (7), the third valve (8), the fourth valve (9), the fifth valve (10), the sixth valve (11), the seventh valve (12), the eighth valve (13) and the ninth valve (14), opening the first air purge (3), the second air purge (4) and the third air purge (5), and purging the first pipeline (16), the purging time is 5-10 minutes, and the purging flow rate is 50-100 ml / min; Step S3, closing the first valve (6), the second valve (7), the third valve (8), the fifth valve (10), the sixth valve (11), the seventh valve (12), the eighth valve (13) and the ninth valve (14), and keeping the fourth valve (9) open; Step S4, setting the required tracer gas injection amount on the gas flow meter (15), denoted as q in , unit: ml / h; Step S5, using a fresh air volume measurement method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant in claim 7 to measure the fresh air volume Qn of the habitable area (106) of the main control room, unit: m 3 / h; Step S6, using the method for measuring the free volume of the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 9 to measure the free volume of the habitable area of ​​the main control room (106), denoted as V, unit: m 3 ; Step S7, calculating the ventilation rate A=Qn / V of the habitable area (106) of the main control room; Step S8, calculating the time T when the tracer gas in the habitable area (106) of the main control room reaches the final equilibrium concentration of 95% 95％ =3 / A; Step S9, opening the first gas cylinder (1) and injecting the high-purity sulfur hexafluoride gas into the first pipeline (16); Step S10, adjusting the first valve (6) to a desired opening; Step S11, the injection flow rate of the first gas cylinder (1) is q in1 , unit: ml / h, the continuous injection time of the high-purity sulfur hexafluoride gas T1=2 / A*n; the n represents the dilution multiple of the diluted sulfur hexafluoride gas; Step S12, after the injection time T1 is reached, closing the first gas cylinder (1); Step S13, using the first air purge device (3) to purge the first pipeline (16) for 3-5 minutes, with a purge flow rate of 50-100 ml / min; Step S14, closing the first valve (6) and the ninth valve (14); Step S15, opening the second gas cylinder (2) and injecting the diluted sulfur hexafluoride gas into the first pipeline (16); Step S16, opening the eighth valve (13); Step S17, adjusting the seventh valve (12) to a desired opening; Step S18, the injection flow rate of the second gas cylinder (2) is q in2 , unit: ml / h, the continuous injection time of the diluted sulfur hexafluoride gas T2≥1 / A; Step S19, when the tracer gas injection time reaches Tt=2 / A*n+1 / A, start the tracer gas sampling device to perform the first sampling on the 40 sampling points, and the tracer gas injection time is counted from the injection of the high-purity gas; Step S20: In the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C 1i , 1≤i≤40, unit: ppm, the average concentration of the first tracer gas at the 40 sampling points is C1, unit: ppm, each C 1i The deviation from the stated C1 does not exceed 10%; Step S21, a separate air volume measurement sampling point (146) is respectively set on the twelfth ventilation pipeline (123) and the thirteenth ventilation pipeline (124) upstream of the fan of the ventilation system in the habitable area of ​​the main control room, and the first sampling is performed at the two separate air volume measurement sampling points (146). The average value of the tracer gas concentration at the two separate air volume measurement sampling points (146) is recorded as C b1 , unit: ppm, the C b1 The deviation from the stated C1 does not exceed 10%; Step S22, after T hours, sampling the 40 sampling points for the second time; T≥0.25h; Step S23, in the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C 2i , 1≤i≤40, unit: ppm, each of the C 2i The values ​​are all after deducting the background concentration; The average concentration of the second tracer gas at the 40 sampling points is C2, unit: ppm, and each C 2i The deviation from the stated C2 does not exceed 10%; Step S24, a second sampling is performed at the two separate air volume measurement sampling points (146), the tracer gas concentrations at the two separate air volume measurement sampling points (146) are subtracted from the background concentration, and then the average value of the tracer gas concentrations at the two separate air volume measurement sampling points (146) is calculated and recorded as C b2 , unit: ppm, the C b2 The deviation from the stated C2 does not exceed 10%; Step S25, determine (C2-C1) / T<0.05*q in2 / V is established; Step S26, if the inequality in step S25 holds, the test ends, and C2 is used as the final equilibrium concentration of the tracer gas in the habitable area of ​​the main control room of this test; Step S27, the continuous injection direct test ends; Step S28, closing the second gas cylinder (2); Step S29, using the third air purge device (5) to purge the first pipeline (16), with a purge time of 3-5 minutes and a purge flow rate of 50-100 ml / min; Step S30, closing the sixth valve (11), the seventh valve (12) and the eighth valve (13); Step S31, closing the fourth valve (9); Step S32, opening the fifth valve (10); Step S33, using the second air purge device (4) to purge the first pipeline (16), the purge time is 3-5 minutes, and the purge flow rate is 50-100 ml / min; Step S34, closing the fifth valve (10); Step S35, If in step S20, any one of the C 1i Deviation from the stated C1 exceeds 10%; Alternatively, in step S21, the C b1 Deviation from the stated C1 exceeds 10%; Alternatively, in step S23, any one of the C 2i Deviation from said C2 exceeds 10%; Alternatively, in step S24, the C b2 Deviation from said C2 exceeds 10%; Alternatively, the inequality in step S25 does not hold; Then it is necessary to find the cause, and after solving the problem, return to step S2 and retest; Step S36, calculating the internal leakage of the habitable area (106) of the main control room: Q leak =q in2 / C2-Q n , unit: m 3 / h; Step S37, repeat the test n times, n≥1, calculate the internal leakage of the habitable area (106) of the main control room respectively, and use the average value as the final test result.

11. A method for evaluating measurement results of the method for measuring leakage in the habitable area of ​​the main control room of a nuclear power plant as claimed in claim 10, comprising the following steps: Step S1, determining the resolution δ1 of the gas flow meter (15); unit: ml / h; Step S2, determining the tracer gas injection flow rate q; Unit: ml / h; Step S3, calculating the uncertainty u(q) of the tracer gas injection flow rate q = 0.29δ1; unit: ml / min; Step S4, determining the resolution δ2 of the tracer gas analyzer; unit :ppm; Step S5, calculating the tracer gas concentration C at the air volume measurement point n =(C n1 +C n2 +C n3 ) / 3; unit: ppm; Step S6, calculating the uncertainty of the tracer gas concentration u(C n )=0.167δ2; unit: ppm; Step S7, using the fresh air volume measurement method in claim 7 to calculate the fresh air volume Qn = q / C n ; Unit: m 3 / h; Step S8, calculating the uncertainty of the fresh air volume, Unit: m 3 / h; Step S9, in the jth test, in the first sampling, the first tracer gas concentration corresponding to the 40 sampling points is recorded as C j1i In the second sampling, the second tracer gas concentration corresponding to the 40 sampling points is recorded as C j2i ; 1≤j≤n, 1≤i≤40; Unit: ppm; Step S10, calculating the uncertainty u(C j1i )=u(C j2i )=0.29δ2; Unit :ppm; Step S11, calculating the average concentration of the second tracer gas at the 40 sampling points of the second sampling of the jth test Unit: ppm; Step S12, calculating the internal leakage of the jth test of the habitable area (106) of the main control room Q j , leak =q j，in / C j2 -Q n ; Unit: m 3 / h;q j，in It refers to the injection flow rate of diluted tracer gas in the jth test, ml / h; Step S13, calculating the internal leakage of the habitable area (106) of the main control room Unit: m 3 / h; Step S14, calculating the uncertainty of the leakage in the habitable area (106) of the main control room Unit: m 3 / h; Step S15, calculating the uncertainty of n measurements of the internal leakage of the habitable area (106) of the main control room Unit: m 3 / h; Step S16, determine the t corresponding to the t distribution when the degree of freedom is (n-1) 95％ value; Step S17, calculating the comprehensive uncertainty of n measurements of the internal leakage of the habitable area (106) of the main control room: U(Q e,leak ) = t 95％ *u(Q e,leak ); Unit: m 3 / h; Step S18, draw the conclusion: the internal leakage test result Q of the habitable area (106) of the main control room is e,leak , confidence interval [-U(Q e,leak ),U(Q e,leak )], confidence probability 95%; unit: m 3 / h.

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