CN106323356A - Vehicle evaporative emission operation loss VOCs emission factor measurement method - Google Patents

Abstract

The invention discloses a vehicle evaporative emission operation loss VOCs emission factor measurement method. Based on serial applications of multiple modes, the operation loss emission can be indirectly and quantitatively judged. The method comprises steps of light-duty gasoline vehicle and heavy-duty diesel vehicle exhaust emission laboratory measurement, light-duty gasoline vehicle hot dipping emission VOCs emission factor laboratory measurement, actual road vehicle VOCs comprehensive emission factor tunnel measurement, VOCs species chemical composition analysis and model analysis. Based on the light-duty gasoline vehicle exhaust emission and hot dipping emission in a laboratory airtight cabin or a drum, a single process characteristic source spectrum is built. The model analysis comprises chemical mass balance model analysis and comprehensive emission factor deduction. Operation loss emission factors of a vehicle group in an actual road condition are finally built. The technology makes up for the existing lacked vehicle VOCs operation loss emission testing condition, emission errors caused by inconsistency between the experimental condition and the actual condition when the vehicle VOCs operation loss is tested in the laboratory in the past can be solved, and the vehicle VOCs operation loss emission factors can be accurately acquired.

Description

A kind of motor vehicles discharge vaporization running losses VOCs emission factor measuring method

Technical field

The invention belongs to motor vehicles VOCs discharge vaporization technical field, run particularly to a kind of motor vehicles discharge vaporization and damage Lose VOCs emission factor measuring method.

Background technology

Motor vehicles VOCs discharge is the main source of VOCs in urban atmosphere, and its discharge process mainly has exhaust emissions and steaming Send a manuscript to the compositor and put two classes.Along with the progress of exhaust emission control technology, discharge vaporization contribution in motor vehicles VOCs always discharges is day by day Significantly.Discharge vaporization approach mainly includes discharging between daytime, hot dipping discharge, refuel discharge, infiltration discharge and running losses etc..Discharge Mechanism specifically includes that 1. cause the oil gas generated in fuel tank to expand owing to temperature raises, and enters air via air vent；2. oil product Component molecular, via osmosis, enters air through oil piping system；3. exchanging due to gas-liquid when refueling, oil gas is via oil filler Enter air.The discharge vaporization method of testing of current international main flow is closed cabin method of testing, and relevant main flow testing process has The motor vehicles discharge vaporization method of testing of U.S. EPA and the gasoline car emission control regulations of European Union, common protocol is with closed cabin Collect vehicle launch, travel and stop during various process discharge VOCs.Wherein, the emissions measurement of running losses is in standard work The condition operation phase；The mensuration of hot dipping discharge is after engine stop, the stage that car body temperature declines；Vehicle and closed cabin environment Temperature reach balance after, by simulation temperature control with record vehicle daytime between discharge；Closed cabin is derived in canister aerofluxus To record the infiltration discharge of vehicle.In above-mentioned emission factor, hot dipping discharge, discharge between daytime and permeate emission factor at home Directly measured by existing testing process and experiment condition.

The VOCs running losses emission test of motor vehicles is difficult to carry out the most at home, and concrete reason is for completing to test needs The equipment such as the temperature-changeable closed cabin with rotary drum, and domestic currently without the laboratory of test condition can be met, grind the most at present State six draft intended is only capable of rule of thumb indirectly processing the VOCs discharge vaporization running losses of vehicle, there is no specification trolley The testing standard of VOCs discharge vaporization running losses；Additionally, the VOCs running losses discharge of motor vehicles needs based on meeting reality Border road condition measures, and past research have shown that, current experiment condition cannot reflect the activity of vehicle under real road operating mode State.In sum, the measuring of running losses needs with the closed cabin of rotary drum, lab construction, the transformation of existing laboratory and O&M cost is high, and the vehicle-state under measurement condition may not correspond with real road operating mode, causes domestic motor vehicles VOCs discharge vaporization running losses emission factor is difficult to obtain.

Summary of the invention

In order to overcome the shortcoming of above-mentioned prior art, it is an object of the invention to provide a kind of motor vehicles discharge vaporization and run Loss VOCs emission factor measuring method, can measure an area motor vehicles discharge vaporization running losses VOCs emission factor.

To achieve these goals, the technical solution used in the present invention is as follows:

A kind of motor vehicles discharge vaporization running losses VOCs emission factor measuring method, comprises the steps:

Step one: the emission factor of vehicle is surveyed by the laboratory standard method of testing existing according to experiment location Amount, measures discharge VOCs source spectrum species composition simultaneously, and wherein vehicle includes Light-Duty Gasoline Vehicle and heavy-duty diesel vehicle；Emission factor bag Include Light-Duty Gasoline Vehicle hot dipping emission factor, Light-Duty Gasoline Vehicle and the heavy-duty diesel vehicle exhaust emissions factor；

Step 2: to being intended to assess selection tunnel, area, this tunnel environmental data and vehicle in the test period is formed number According to carrying out record, on-the-spot monitoring device continuously is used to carry out VOCs concentration monitor in suitable place；

Step 3: measure and calculate Light-Duty Gasoline Vehicle VOCs combined emission factors in roadway experiment, and deduct laboratory survey The Light-Duty Gasoline Vehicle exhaust emissions factor, calculate this area Light-Duty Gasoline Vehicle VOCs average running losses discharge because of Son；Or obtain, with chemotherapy synergism, the discharge contribution that Light-Duty Gasoline Vehicle VOCs hot dipping is discharged, calculate the light-duty of this area Gasoline car VOCs average running losses emission factor.

Owing to diesel oil volatility is relatively low, heavy-duty diesel vehicle does not the most have a running losses emission factor, the most negligible not Meter.

Domestic not yet have the laboratory test environment meeting motor vehicles VOCs discharge vaporization running losses, at present with existing skill Art is compared, and the present invention can record the VOCs discharge vaporization running losses of motor vehicles under real road operating mode, it is achieved low cost, energy Measure and meet the method for quantitative measuring of motor vehicles VOCs running losses emission factor of real road operating mode for a long time.

Accompanying drawing explanation

Fig. 1 is flow chart of the present invention.

Detailed description of the invention

Embodiments of the present invention are described in detail below in conjunction with the accompanying drawings with embodiment.

As it is shown in figure 1, the present invention has two parallel Technology Ways, the technical scheme being respectively adopted is as follows:

Technological approaches one: environment VOCs mass, wagon flow feature, Light-Duty Gasoline Vehicle and the weight recorded according to repeatedly roadway experiment Type diesel vehicle proportion of composing, resolve Light-Duty Gasoline Vehicle and the respective VOCs of heavy-duty diesel vehicle under real road operating mode always discharge because of Son, and deduct the exhaust emissions factor that laboratory records, obtain under real road operating mode motor vehicles running losses VOCs discharge because of Son, method comprises the following steps.

Step one: according to the vehicle VOCs discharge standard method of testing that this area is existing, select representative light vapor Oil car and heavy-duty diesel vehicle record Light-Duty Gasoline Vehicle and the total carbon hydrocarbon exhaust emissions factor of heavy-duty diesel vehicle of routine, are designated as respectively Light-Duty Gasoline Vehicle exhaust emissions factor EF_LD,TPAnd heavy-duty diesel vehicle exhaust emissions factor EF_HD,TP。

Step 2: this area's road environment and wagon flow feature are investigated, using search and determine suitable tunnel as Road test section, the environmental requirement in tunnel includes that road is smooth and straight, and in section, gas is subject in the diffusion zone of wagon flow Limit, without to outward opening in addition to gateway in tunnel, the atmospheric environment comprising sampled point is stable, without obvious convection current, test section The most unglazed photograph in territory, the neighbouring nothing obvious VOCs emission source in addition to road moving source.

Step 3: with the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs concentration to obtain vehicle VOCs emission factor, according to emission mechanism, the vehicle VOCs discharge quality recorded is total equal to Light-Duty Gasoline Vehicle VOCs during measuring Emission factor and the total emission factor of heavy-duty diesel vehicle VOCs are multiplied by the adduction after vehicle proportion of composing respectively, and formula is E=XL+ YH, in formula X be Light-Duty Gasoline Vehicle vehicle number quantity during testing than percentage, Y be heavy-duty diesel vehicle vehicle number test during Quantity than percentage, L is the total emission factor of VOCs of Light-Duty Gasoline Vehicle during test, and H is heavy-duty diesel vehicle during test The total emission factor of VOCs.To total VOCs emission factor, Light-Duty Gasoline Vehicle vehicle number and heavy-duty diesel vehicle car after repeatedly testing Number calculates equation of linear regression, obtains the total emission factor of VOCs of this area's Light-Duty Gasoline Vehicle and heavy-duty diesel vehicle.

Step 4: according to emission mechanism, Light-Duty Gasoline Vehicle VOCs running losses emission factor is that Light-Duty Gasoline Vehicle VOCs is total Emission factor deducts the VOCs exhaust emissions factor that Light-Duty Gasoline Vehicle is conventional, and formula is L_RL=L-EF_LD,TP。

Technological approaches two: according to motor vehicles VOCs exhaust emissions and discharge vaporization source component spectrum, wagon flow feature and light vapor Oil car and heavy-duty diesel vehicle proportion of composing, applied chemistry Mass balance model, directly parse motor vehicles under real road operating mode Running losses VOCs emission factor, method comprises the following steps.

Step one: according to the vehicle VOCs discharge standard method of testing that this area is existing, select representative light vapor Oil car and heavy-duty diesel vehicle record conventional Light-Duty Gasoline Vehicle and the VOCs exhaust emissions of heavy-duty diesel vehicle and hot dipping discharge species Composition, the VOCs species of mensuration include ethane, ethylene, acetylene, ethanol, propane, propylene, normal butane, iso-butane, pentane, different Pentane, 2-methylpentane, 3-methylpentane, normal hexane, methyl cyclopentane, 2-methyl hexane, 3-methyl hexane, 2,2-dimethyl Butane, o-ethyltoluene, m-ethyltoluene, p-ethyltoluene, cis-2-butene, Trans-2-butene, 1-butylene, benzene, toluene, Ortho-xylene, meta-xylene, p-xylene, ethylbenzene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethyl Benzene, acetone, methyl tertiary butyl ether(MTBE).Calculate above-mentioned species respectively at Light-Duty Gasoline Vehicle total VOCs discharge and the total VOCs of heavy-duty diesel vehicle Mass percent in discharge, obtains Light-Duty Gasoline Vehicle VOCs exhaust emissions source component spectrum, Light-Duty Gasoline Vehicle hot dipping emission source group Open score and heavy-duty diesel vehicle exhaust emissions source component spectrum, be designated as S_LD,TP、S_LD,RLAnd S_HD,TP。

Step 2: this area's road environment and wagon flow feature are investigated, using search and determine suitable tunnel as Road test section, the environmental requirement in tunnel includes that road is smooth and straight, and in section, gas is subject in the diffusion zone of wagon flow Limit, without to outward opening in addition to gateway in tunnel, the atmospheric environment comprising sampled point is stable, without obvious convection current, test section The most unglazed photograph in territory, the neighbouring nothing obvious VOCs emission source in addition to road moving source.

Step 3: with the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs species concentration to obtain Comprehensive vehicle VOCs discharge quality and species composition, VOCs discharge quality and species mass percent to repetitive measurement are made even Average, obtains average quality and the receptor components spectrum of vehicle discharge VOCs.

Step 4: select aforementioned 34 VOCs species in the option of species interface of chemotherapy synergism, after operation Obtaining the source contribution value of calculation (Source Contribution Estimate, SCE) of each source spectrum, being respectively divided by %MASS value can Obtain source spectrum S_LD,TP、S_LD,RLAnd S_HD,TPTo the percentage contribution after receptor spectrum A normalization, it is designated as P_LD,TP、P_LD,RLAnd P_HD,TP, by This can calculate the running losses emission factor of vehicle VOCs, and formula isIn formula, L_RLFor vehicle VOCs average running losses emission factor, M_n-1The vehicle VOCs discharge quality measured for n-th, x_n-1For n-th measure light Type gasoline car vehicle number, L is experimental road segment length.

The present invention to implement means as follows:

1, environmental data and vehicle composition data investigation

Environmental characteristic data and the investigation of vehicle composition characteristic data, environmental characteristic to main roads traffic section, this area Including temperature, relative humidity, background VOCs concentration etc., vehicle composition data pass through the light-duty of test segment in including the unit interval Gasoline car vehicle number, heavy-duty diesel vehicle vehicle number and average overall travel speed.

Test segment environmental characteristic data and vehicle form data investigation, and environmental characteristic data include temperature, the wettest Degree, background VOCs concentration etc., vehicle composition data pass through the Light-Duty Gasoline Vehicle vehicle number of test segment, weight in including the unit interval Type diesel vehicle vehicle number and average overall travel speed, above-mentioned data are as the foundation assessing suitable test segment.

Environmental characteristic and the wagon flow feature of selected test segment should meet claimed below:

[1]. road is smooth and straight, long at least 500 meters, for unidirectional wagon flow.

[2]. the environmental data in environmental data in test segment and road vehicle composition data and main traffic section and Vehicle composition data are similar.

[3]. gas is limited to the diffusion zone of wagon flow vertical direction, the monitored area atmospheric environment including sampled point Stable, without obvious convection current.

[4]. the most unglazed photograph in test zone, the neighbouring nothing obvious VOCs emission source in addition to road moving source.

2, vehicle VOCs Routine purges factor acquisition methods

Selecting the representative vehicle in this area, establishing criteria experiment flow carries out exhaust emission testing and discharge vaporization is surveyed Examination, puts, in all kinds of emission test stage sart point in times t1 and end time, the total carbon hydrocarbonaceous amount that t4 record standard instrument records, For calculating total VOC emission factor, formula is as follows:

EF_v,j=ε_j,t4-ε_j,t1 (4)

In formula, EF is VOCs emission factor, and v is vehicle class, and j is discharge approach, and ε is the VOCs matter that reference instrument records Amount.According to emission mechanism, emission factor is divided into the Light-Duty Gasoline Vehicle exhaust emissions factor, the Light-Duty Gasoline Vehicle discharge vaporization factor and weight Type exhaust gas from diesel vehicle emission factor, is designated as EF respectively_LD,TP、EF_LD,VAPAnd EF_HD,TP。

3, vehicle VOCs average running losses emission factor computational methods

With the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs concentration to obtain vehicle VOCs thing Planting discharge quality, VOCs discharge quality computing formula is as follows:

M=(C_out-C_in)·V (5)

In formula, C_inFor link entry VOCs concentration, C_outFor road way outlet VOCs species concentration, V is that gas diffuser amasss. N measurement result of VOC species is sequentially numbered, such as m₁,m₂,……m_n。

The Light-Duty Gasoline Vehicle by experiment road and heavy-duty diesel vehicle number is recorded, between measuring n time during double sampling Light-Duty Gasoline Vehicle number is numbered, such as x₁,x₂,……x_n-1；Heavy-duty diesel vehicle number between measuring n time is numbered, such as y₁, y₂,……y_n-1.To vehicle number normalization, obtain x_n-1With y_n-1Normalized value X_αAnd Y_α, it may be assumed that

X_α+Y_α=1 (α=1,2 ... n-1) (6)

According to emission mechanism, it is believed that the VOCs VOCs discharge matter equal to period by vehicle of poor quality between twice measurement Amount, the VOCs discharge quality between measuring n time is numbered, such as M₁,M₂,……M_n-1.Then combined emission factors is defined as:

$E_{\mathrm{\α}}=\frac{M_{\mathrm{\α}}}{(x_{\mathrm{\α}}+y_{\mathrm{\α}})l}---\left(7\right)$

In formula, l is experiment link length.

According to emission mechanism, for all gross vehicle emission factors in experiment, following equation should be met:

E_α=X_αL+Y_αH (8)

In formula, L and H is respectively the VOCs emission factor of Light-Duty Gasoline Vehicle and heavy-duty diesel vehicle, and according to formula 6, formula 8 is rewritable For:

E_α=(L-H) X_α+H_i,α (9)

OrderAnd definitionTo E_αAnd X_αSeek equation of linear regression, it may be assumed that

$\widehat{\mathrm{\α}}=\frac{{\Σ}_{\mathrm{\α}=1}^{n-1}{E}_{\mathrm{\α}}{X}_{\mathrm{\α}}-(n-1)\stackrel{\‾}{EX}}{{\Σ}_{\mathrm{\α}=1}^{n-1}{X}_{\mathrm{\α}}^2-(n-1){\stackrel{\‾}{X}}^2}---\left(10\right)$

$\hat{b}={\stackrel{\‾}{E}}_{\mathrm{\α}}-\hat{a}{\stackrel{\‾}{X}}_{\mathrm{\α}}---\left(11\right)$

Therefore, in experiment, the average emission factors of the VOCs species of vehicle may be defined as:

$L=\hat{a}+\hat{b}---\left(12\right)$

$H=\hat{b}---\left(13\right)$

According to emission mechanism, L contain the tail gas VOCs emission factor of light-duty vehicle and running losses VOCs discharge because of Son, therefore the running losses emission factor L of the VOCs species of vehicle in experiment_RLIt is defined as:

L_RL=L-EF_LD,TP (14)

4, vehicle VOCs average running losses emission factor is calculated with chemotherapy synergism

Comprehensive all kinds of discharge approach and emission mechanism, through literature survey etc., select tool table source 34 VOCs of component Species are analyzed, including ethane, ethylene, acetylene, ethanol, propane, propylene, normal butane, iso-butane, pentane, isopentane, 2- Methylpentane, 3-methylpentane, normal hexane, methyl cyclopentane, 2-methyl hexane, 3-methyl hexane, 2,2-dimethylbutane, O-ethyltoluene, m-ethyltoluene, p-ethyltoluene, cis-2-butene, Trans-2-butene, 1-butylene, benzene, toluene, o-two Toluene, meta-xylene, p-xylene, ethylbenzene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, third Ketone, methyl tertiary butyl ether(MTBE) etc..

Species i is calculated respectively in Light-Duty Gasoline Vehicle exhaust emissions, Light-Duty Gasoline Vehicle fortune according to formula 15 and preceding paragraph species composition Relative mass percentage ratio in row loss discharge and heavy-duty diesel vehicle exhaust emissions, due to the similarity of discharge process Yu mechanism, Running losses emission test result is replaced with the experimental result of hot dipping emission test.

For record VOCs discharge species proportion of composing, in experiment start and at the end of use stainless-steel vacuum Soviet Union horse tank respectively adopt Collect a gaseous sample.Material comprises the rustless steel sample can of 3.2 liters, the teflon pipe of 1/4th inch calibre, band granule The rustless steel Sampler valves of thing filtering function.Rustless steel sample can completes 6 clean cycle before experiment starts, and a cleaning follows Ring is defined as extracting gas in sample can out, until vacuum reaches 100 millitorrs in tank, is hereafter passed through 99.999% purity nitrogen gas straight In tank, pressure reaches 23psi, needs to extract gas in tank again out after completing six clean cycle, and making vacuum in tank is 30 millitorrs. Sampler valves is connected before starting by emission test experiment with sample can, uses teflon pipe to be arranged with experimental provision by valve air inlet QI KOU links, and the experiment time started is t1, and experiment starts to open sampling valve simultaneously and imports in sample can by vehicle exhaust, treats system Pressure reach constant after close sampling valve, and record sample end time t2；The experiment end time is t4, and experiment terminates sampling and opens Time beginning is t3, and t3 is equal to t4-t2+t1, is connected with sample can by Sampler valves when t3, uses teflon pipe to be entered by valve QI KOU is connected with experimental provision air vent, and opens sampling valve, treats that experiment terminates to complete sampling simultaneously.

Sample use gas chromatogram tandem mass spectrometer analyze, analyze species at least include ethane, ethylene, acetylene, ethanol, third Alkane, propylene, normal butane, iso-butane, pentane, isopentane, 2-methylpentane, 3-methylpentane, normal hexane, methyl cyclopentane, 2-methyl hexane, 3-methyl hexane, 2,2-dimethylbutane, o-ethyltoluene, m-ethyltoluene, p-ethyltoluene, cis- 2-butylene, Trans-2-butene, 1-butylene, benzene, toluene, ortho-xylene, meta-xylene, p-xylene, ethylbenzene, 1,2,3-front three Base benzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, acetone, methyl tertiary butyl ether(MTBE).According to above-mentioned species in analytical tool Response time numbering, such as ethane numbered 1, ethylene numbered 2, the rest may be inferred.

The sample concentration obtained after sampling analysis during t1 in the experiment of Light-Duty Gasoline Vehicle exhaust emissions is designated as C_1,LD,TP,t1, C_2,LD,TP,t1……C_34,LD,TP,t1；The sample concentration obtained after sampling analysis during t3 in the experiment of Light-Duty Gasoline Vehicle exhaust emissions is designated as C_1,LD,TP,t3,C_2,LD,TP,t3……C_34,LD,TP,t3.The sample obtained after sampling analysis during t1 in heavy gasoline motor car exhausted gas experiment Product concentration is designated as C_1,HD,TP,t1,C_2,HD,TP,t1……C_34,HD,TP,t1；Sampling analysis during t3 in heavy gasoline motor car exhausted gas experiment After the sample concentration that obtains be designated as C_1,HD,TP,t3,C_2,HD,TP,t3……C_34,HD,TP,t3.T1 in Light-Duty Gasoline Vehicle hot dipping Emission test Time sampling analysis after the sample concentration that obtains be designated as C_1,LD,VAP,t1,C_2,LD,VAP,t1……C_34,LD,VAP,t1；Light-Duty Gasoline Vehicle tail gas The sample concentration obtained after sampling analysis during t3 in Emission test is designated as C_1,LD,VAP,t3,C_2,LD,VAP,t3……C_34,LD,VAP,t3。

Calculating VOCs and discharge species relative mass percentage ratio, formula is as follows:

$S_{i,v,j}=\frac{C_{i,v,j,t4}-C_{i,v,j,t1}}{{\Σ}_{i=1}^{34}{C}_{i,v,j,t4}-C_{i,v,j,t1}}---\left(15\right)$

In formula, i is VOCs species, and v is type of vehicle, and j is discharge approach, and S is the confrontation mutually in discharge of the VOCs species Amount percentage ratio.

With the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs concentration to obtain vehicle VOCs thing Planting discharge quality, VOCs species discharge quality computing formula is as follows:

m_i=(C_i,out-C_i,in)·V (16)

In formula, C_i,inFor link entry VOCs species i concentration, C_i,outFor road way outlet VOCs species i concentration, V is gas Diffusion volume, is sequentially numbered, such as m n measurement result of VOC species₁,m₂,……m_n。

According to emission mechanism, it is believed that the VOCs VOCs discharge matter equal to period by vehicle of poor quality between twice measurement Amount, the VOCs species i discharge quality between measuring n time is numbered, such as M_i,1,M_i,2,……M_i,n-1.Between n time is measured VOCs species i discharge quality averaging normalization, formula is as follows:

$A_i=\frac{\stackrel{\‾}{M_{n,i}}}{{\Σ}_{i=1}^{34}\stackrel{\‾}{M_{n,i}}}---\left(17\right)$

In formula, A_iAverage relative content in measuring in n time for VOCs species i, in experiment, the species of all surveys is average Relative amount summation is 1, is calculated receptor VOCs component by model and composes.

Aforementioned 34 VOCs species are selected, fortune in the option of species interface of chemotherapy synergism software (CMB8.2) Obtain the source contribution value of calculation (Source Contribution Estimate, SCE) of each source spectrum after row, be respectively divided by %MASS Available source spectrum S of value_LD,TP、S_LD,RLAnd S_DD,TPTo the percentage contribution after receptor spectrum A normalization, it is designated as P_LD,TP、P_LD,RLAnd P_HD,TP.Therefore, vehicle VOCs average running losses emission factor computing formula is as follows:

$L_{RL}=P_{LD,RL}\·\frac{\stackrel{\‾}{M_{n-1}}}{\stackrel{\‾}{x_{n-1}}}\·\frac{1}{l}---\left(18\right)$

In formula, L_RLFor vehicle VOCs average running losses emission factor, M_n-1The vehicle VOCs measured for n-th discharges matter Amount, x_n-1The Light-Duty Gasoline Vehicle vehicle number measured for n-th, L is experimental road segment length.

Claims (9)

1. a motor vehicles discharge vaporization running losses VOCs emission factor measuring method, it is characterised in that comprise the following steps:

Step one: the emission factor of vehicle is measured by the laboratory standard method of testing existing according to experiment location, with Time measure discharge VOCs source spectrum species composition, wherein vehicle includes Light-Duty Gasoline Vehicle and heavy-duty diesel vehicle；Emission factor includes gently Type gasoline car hot dipping emission factor, Light-Duty Gasoline Vehicle and the heavy-duty diesel vehicle exhaust emissions factor；

Step 2: to being intended to assess selection tunnel, area, enters in environmental data and the vehicle composition data of test period this tunnel Row record, uses on-the-spot monitoring device continuously to carry out VOCs concentration monitor in suitable place；

Step 3: measure and calculate Light-Duty Gasoline Vehicle VOCs combined emission factors in roadway experiment, and deduct what laboratory recorded The Light-Duty Gasoline Vehicle exhaust emissions factor, calculates the Light-Duty Gasoline Vehicle VOCs average running losses emission factor of this area；Or Obtain the discharge contribution of Light-Duty Gasoline Vehicle VOCs hot dipping discharge with chemotherapy synergism, calculate the Light-Duty Gasoline Vehicle of this area VOCs average running losses emission factor.

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step one, the measuring method of emission factor is as follows:

[1]. test selects the representative vehicle in this area, and establishing criteria experiment flow carries out exhaust emission testing and hot dipping row Putting test, according to emission mechanism, emission factor is divided into the Light-Duty Gasoline Vehicle exhaust emissions factor, Light-Duty Gasoline Vehicle hot dipping emission factor And the heavy-duty diesel vehicle exhaust emissions factor, it is designated as EF respectively_LD,TP、EF_LD,VAPAnd EF_HD,TP；

[2]. in exhaust emission testing stage sart point in time t₁And end time point t₄The measuring instrument that record standard specifies records Total carbon hydrocarbonaceous amount difference, for calculating the tail gas total carbon hydrocarbon emission factor of vehicle, formula is EF_v,TPFor VOCs emission factor, v is vehicle class, and d is the VMT Vehicle-Miles of Travel during test, ε_TP,t4T is put for the end time₄ The total carbon hydrocarbonaceous amount of record, ε_TP,t1For sart point in time t₁The total carbon hydrocarbonaceous amount of record；

[3]. in hot dipping emission test stage sart point in time t₁And end time point t₄The measuring instrument that record standard specifies records Total carbon hydrocarbonaceous amount difference, for calculating the hot dipping total carbon hydrocarbon emission factor of vehicle, formula is EF_LD,VAP=ε_VAP,t4-ε_VAP,t1, EF_LD,VAPFor VOCs emission factor, ε_VAP,t4T is put for the end time₄The total carbon hydrocarbonaceous amount of record, ε_VAP,t1For sart point in time t₁Note The total carbon hydrocarbonaceous amount of record.

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step one, VOCs source spectrum species composition measuring method is as follows:

[1]. rustless steel sample can completes before experiment starts six clean cycle, and a clean cycle is defined as sample can In interior gas is drawn to tank, vacuum reaches 100 millitorrs, is hereafter passed through 99.999% purity nitrogen gas until pressure reaches in tank 23psi, needs to extract gas in tank again out after completing six clean cycle, and making vacuum in tank is 30 millitorrs；

[2]. the rustless steel Sampler valves of band particulate matter filtering function is connected before starting by emission test experiment with sample can, uses Sampler valves air inlet is connected by the teflon pipe of 1/4th inch calibre with experimental provision air vent, experiment the time started be t₁, experiment starts to open sampling valve simultaneously and import in sample can by vehicle exhaust, until system pressure reach constant after close sampling Valve, and record sample end time t₂；The experiment end time is t₄, it is t that experiment terminates sample start times₃, and t₃Need to be equal to t₄-t₂+t₁, in t₃Time Sampler valves is connected with sample can, use teflon pipe by valve air inlet and experimental provision air vent Connect, and open sampling valve, treat that experiment terminates to complete sampling simultaneously；

[3]. sample use gas chromatogram tandem mass spectrometer analyze, analyze species at least include ethane, ethylene, acetylene, ethanol, third Alkane, propylene, normal butane, iso-butane, pentane, isopentane, 2-methylpentane, 3-methylpentane, normal hexane, methyl cyclopentane, 2-methyl hexane, 3-methyl hexane, 2,2-dimethylbutane, o-ethyltoluene, m-ethyltoluene, p-ethyltoluene, cis- 2-butylene, Trans-2-butene, 1-butylene, benzene, toluene, ortho-xylene, meta-xylene, p-xylene, ethylbenzene, 1,2,3-front three Base benzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, acetone, methyl tertiary butyl ether(MTBE)；

[4]. according to analytical tool response time, preceding paragraph species are numbered, t in the experiment of Light-Duty Gasoline Vehicle exhaust emissions₁Time sampling point The sample concentration obtained after analysis is designated as C successively_1,LD,TP,t1,C_2,LD,TP,t1……C_34,LD,TP,t1；Light-Duty Gasoline Vehicle exhaust emissions is real Test middle t₃Time sampling analysis after the sample concentration that obtains be designated as C_1,LD,TP,t4,C_2,LD,TP,t3……C_34,LD,TP,t3；The heavy gasoline tailstock T in gas Emission test₁Time sampling analysis after the sample concentration that obtains be designated as C_1,HD,TP,t1,C_2,HD,TP,t1……C_34,HD,TP,t1；Heavy T in gasoline motor car exhausted gas experiment₃Time sampling analysis after the sample concentration that obtains be designated as C_1,HD,TP,t3,C_2,HD,TP,t3…… C_34,HD,TP,t3.T in Light-Duty Gasoline Vehicle hot dipping Emission test₁Time sampling analysis after the sample concentration that obtains be designated as C_1,LD,VAP,t1, C_{2, LD, VAP, t1}……C_34,LD,VAP,t1；T in the experiment of Light-Duty Gasoline Vehicle exhaust emissions₃Time sampling analysis after obtain sample concentration note For C_1,LD,VAP,t3,C_2,LD,VAP,t3……C_34,LD,VAP,t3；

[5]. calculating VOCs and discharge species relative mass percentage ratio, formula isI is VOCs thing Kind, v is type of vehicle, and j is discharge approach, S_i,v,jFor VOCs species relative mass percentage ratio in discharge, experiment records The relative mass percentage ratio summation of all VOCs species be 1, constitute Light-Duty Gasoline Vehicle tail gas VOCs emission source component spectrum, light-duty Gasoline car hot dipping emission source component spectrum and heavy-duty diesel vehicle exhaust emissions source component spectrum are designated as S respectively_LD,TP、S_LD,RLAnd S_HD,TP。

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step 2, vehicle composition data are the wagon flow feature of heavy traffic period in the middle of one day, averagely travel speed including vehicle Degree, by investigating the vehicle number in section, the Light-Duty Gasoline Vehicle passed through in the unit interval and heavy-duty diesel vehicle vehicle in the unit interval Hundreds of proportions by subtraction.

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step 2, tunnel meets following feature:

[1]. road is smooth and straight, long at least 500 meters, for unidirectional wagon flow；

[2]. environmental data and road vehicle in test segment form data and the environmental data in main traffic section and vehicle Composition data are similar；

[3]. in tunnel in addition to gateway without other to outward opening, wagon flow vertical direction atmospheric environment is stable, without obvious convection current；

[4]. the most unglazed photograph in test zone, neighbouring without obvious VOCs emission source in addition to road moving source.

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step 2, on-the-spot monitoring device and its set-up site continuously meet following feature:

[1]. equipment possesses continuous monitoring function under real road environment, and sampling analysis interval cannot be greater than 30 minutes, can be given The VOCs species concentration of sampling analysis time point, ambient temperature and humidity, and the recordable preservation of analysis result；

[2]. the VOCs species at least including that preceding paragraph step 2 is listed can be analyzed；

[3]. set-up site at least includes at section entrance 100 meters and at section exports 100 meters, and sampled point is away from ground level At least 1 meter, without obvious barrier in addition to guardrail near set-up site.

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 1, it is characterised in that In described step 3, in roadway experiment, Light-Duty Gasoline Vehicle VOCs combined emission factors computational methods are as follows:

[1]. with the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs concentration to calculate vehicle VOCs thing Plant discharge quality, VOCs discharge quality computing formula m=(C_out-C_in) V, C_inFor link entry VOCs concentration, C_outFor road Outlet VOCs species concentration, V is that gas diffuser amasss, and is sequentially numbered n measurement result of VOC species into m₁, m₂,……m_n；

[2]. record the Light-Duty Gasoline Vehicle by experiment road and heavy-duty diesel vehicle number during twice measurement, by n measurement phase Between the Light-Duty Gasoline Vehicle number that passes through be designated as x respectively₁,x₂,……x_n-1；Heavy-duty diesel vehicle number between measuring n time is designated as y respectively₁, y₂,……y_n-1, to vehicle number normalization, obtain normalized value X_αAnd Y_α, i.e. X_α+Y_α=1 (α=1,2 ... n-1)；

[3]. the VOCs VOCs discharge quality equal to period by vehicle of poor quality between twice measurement, between n time is measured VOCs discharge quality is designated as M respectively₁,M₂,……M_n-1, then combined emission factors is defined asIn formula, l is real Test link length；

[4]. in experiment, vehicle combined emission factors answers coincidence formula E_α=X_αL+Y_αH, L and H are respectively Light-Duty Gasoline Vehicle and heavy type The total emission factor of VOCs of diesel vehicle；

[5]. orderAnd orderTo E_αAnd X_αSeek equation of linear regression, obtain AndTherefore, in experiment, the total emission factor of the VOCs of Light-Duty Gasoline Vehicle and heavy-duty diesel vehicle is defined asAnd

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 7, it is characterised in that In described step 3, Light-Duty Gasoline Vehicle VOCs average running losses emission factor L_RLIt is defined as L_RL=L-EF_LD,TP。

Motor vehicles discharge vaporization running losses VOCs emission factor measuring method the most according to claim 7, it is characterised in that In described step 3, obtain the discharge contribution of Light-Duty Gasoline Vehicle VOCs hot dipping discharge with chemotherapy synergism, real to calculate The method of the average running losses emission factor testing the VOCs of middle vehicle is as follows:

[1]. with the continuous monitoring device in scene simultaneously experiments of measuring link entry and outlet VOCs concentration to obtain vehicle VOCs thing Planting discharge quality, VOCs species discharge quality computing formula is m_i=(C_i,out-C_i,in) V, C_i,inFor link entry VOCs species I concentration, C_i,outFor road way outlet VOCs species i concentration, V is that gas diffuser amasss, to n measurement result of VOC species sequentially It is numbered as m₁,m₂,……m_n；

[2]. the VOCs VOCs discharge quality equal to period by vehicle of poor quality between twice measurement, between n time is measured VOCs species i discharge quality is numbered as M_i,1,M_i,2,……M_i,n-1；VOCs species i discharge quality between measuring n time is asked Average normalization, formula isA_iAverage relative content in measuring in n time for VOCs species i, experiment In the average relative content summation of species of all surveys be 1, constitute receptor VOCs component spectrum；

[3]. in the option of species interface of chemotherapy synergism, select aforementioned 34 VOCs species, after operation, obtain each row Put source contribution value of calculation (Source Contribution Estimate, SCE), be respectively divided by %MASS and be worth to source spectrum S_LD,TP、S_LD,RLAnd S_HD,TPTo the percentage contribution after receptor spectrum A normalization, it is designated as P_LD,TP、P_LD,RLAnd P_HD,TP；Therefore, vehicle VOCs average running losses emission factor computing formula isL_RLAveragely run for vehicle VOCs Loss emission factor, M_n-1The vehicle VOCs discharge quality measured for n-th, x_n-1The Light-Duty Gasoline Vehicle vehicle measured for n-th Number, l is experimental road segment length.