Emission accounting method for non-road mobile machinery operation process based on remote monitoring data

Abstract

The present invention discloses a method for calculating emissions during the operation of non-road mobile machinery based on remote monitoring data. The method comprises the following steps: removing invalid data and invalid data containing invalid NOx values ​​from the daily monitoring data uploaded daily by the non-road mobile machinery to the remote monitoring platform; determining valid data according to a valid data determination program; first calculating the instantaneous emissions of gaseous pollutants and the instantaneous power of the diesel engine; then calculating the window average power percentage; determining the effective power-based window based on the window average power percentage; calculating the effective power-based window ratio emission; counting the number of effective power-based windows whose effective power-based window ratio emission meets the pollutant emission limit; and calculating the ratio of the effective power-based window ratio to the total number of effective power-based windows; and if the proportion of effective power-based windows exceeding the pollutant emission limit exceeds a predetermined threshold, the daily emissions are deemed to exceed the limit. The present invention enables remote monitoring of emissions during the operation of non-road mobile machinery.

Description

Technical Field

[0001] The present invention relates to the technical field of remote monitoring and testing of emissions from non-road mobile machinery, and in particular to a method for calculating emissions during the operation of non-road mobile machinery based on remote monitoring data. Background Art

[0002] Currently, the problem of mobile source emissions is becoming increasingly prominent and is a major source of air pollution. According to relevant reports, automobiles (both light and heavy) emit large amounts of nitrogen oxides and particulate matter. Non-road mobile machinery emissions are even worse, and emission control is relatively slow and difficult: non-road mobile machinery is of various types and widely distributed, especially construction machinery, most of which work in cities and cannot be restricted; non-road mobile machinery works intermittently, and the life of each unit is long and the replacement cycle is long; at the same time, due to the special operating conditions, most of them cannot be electrified and can only continue to be powered by diesel. These problems have led to a large number of non-road mobile machinery with different emission stages scattered in cities for a long time in the future. These machines will emit large amounts of primary and secondary particles, replacing heavy-duty diesel vehicles as the main source of urban mobile source pollution.

[0003] To control emissions from non-road mobile machinery, many cities have introduced the concept of "low-emission zones," requiring high-emission machinery to remain outside these zones. At the same time, for machinery with lower emissions, DPFs and SCRs are being retrofitted to reduce emissions. These measures have reduced urban air pollution from non-road mobile machinery to a certain extent, but they have also brought new regulatory challenges:

[0004] 1. Mechanical work is often stationary for short periods of time but highly mobile for extended periods. Different regulatory requirements exist within and outside low-emission zones, complicating law enforcement. 2. The post-processing market for machinery (including modifications) is chaotic, with widespread tampering and cheating, and a lack of effective regulatory technology. 3. Existing air quality analysis primarily relies on questionnaires and air quality analysis, lacking the tools and technology to evaluate mobile source pollution. This presents significant challenges for the government in formulating emission reduction targets and policies.

[0005] Extensive research and development and testing have demonstrated that the accuracy and authenticity of data received by remote monitoring platforms, as well as the precise positioning of vehicles, meet standard requirements, and remote emissions monitoring systems are gradually maturing. To regulate non-road mobile machinery, the currently published HJ1014-2020 "Technical Requirements for Pollutant Emission Control of Non-road Diesel Mobile Machinery" sets forth requirements for remote monitoring data for emissions from non-road mobile machinery. The "Requirements for Remote Online Monitoring and Networking of Non-road Diesel Mobile Machinery (Draft for Comment)" further clarifies the functional and performance requirements for on-board terminals and precise positioning systems for remote online monitoring of non-road mobile machinery, as well as requirements for enterprise platforms.

[0006] According to Appendix E of HJ1014-2020, "Technical Requirements for Pollutant Emission Control of Non-road Diesel Mobile Machinery," PEMS testing for non-road mobile machinery is required to be conducted during actual operation of the machinery, and methods for data processing and emissions assessment are proposed. However, there is currently no technology that can effectively monitor the actual emissions of non-road mobile machinery, addressing the challenges of regulation, enforcement, and evaluation. Summary of the Invention

[0007] The purpose of the present invention is to address the technical defects existing in the prior art and to provide a non-road mobile machinery operation process emission accounting method based on remote monitoring data. It aims to verify the actual emission level of non-road mobile machinery connected to the remote monitoring platform based on the big data received by the non-road mobile machinery emission remote monitoring platform, and realize supervision. It can verify and calculate the emission data of the actual working process of non-road mobile machinery connected to the remote monitoring platform and identify and mark the excessive-emission machinery, and can be used for law enforcement and supervision by the ecological and environmental authorities.

[0008] The technical solution adopted to achieve the purpose of the present invention is:

[0009] A method for calculating emissions from non-road mobile machinery operations based on remote monitoring data, including:

[0010] Based on the invalid data determination program, the data with invalid NOx values ​​in the daily monitoring data uploaded to the remote monitoring platform by non-road mobile machinery are eliminated and invalid data is determined;

[0011] Determine valid data based on valid data determination procedure;

[0012] Calculate the emission results of valid data; first calculate the instantaneous emissions of gaseous pollutants and the instantaneous power of the diesel engine, then calculate the window average power percentage, determine the effective power base window based on the window average power percentage, calculate the effective power base window ratio emission, count the number of effective power base windows whose effective power base window ratio emissions meet the pollutant emission limit, and calculate the proportion of the total number of effective power base windows; if the proportion of effective power base windows that exceed the pollutant emission limit exceeds the predetermined threshold, it is considered that the daily emissions exceed the standard.

[0013] Among them, the invalid data includes: data where the engine power is less than 10% of the maximum net power; data corresponding to the cold engine state: the coolant temperature of the diesel engine is less than 70°C, and the coolant temperature changes by more than or equal to 2°C within 5 minutes, no later than 20 minutes after the diesel engine is started; data where the ambient temperature is less than 10°C or greater than 38°C or the altitude exceeds 1700m.

[0014] Among them, the invalid data is divided into short invalid data and long invalid data according to the duration; among them, invalid data shorter than 120s is valid data, and valid data shorter than 120s is invalid data; the startup phase after the long invalid data until the exhaust temperature reaches 250°C is invalid data. If the exhaust temperature does not reach 250°C within 240s, the data after 240s is regarded as valid data; the invalid data for 120s after the end of the valid data is valid data.

[0015] Among them, the windows with a window average power percentage greater than 20% are valid power-base windows. If the number of windows with a window average power percentage greater than 20% is less than 50% of the total number of windows, the 20% requirement for the window average power percentage will be gradually reduced in steps of 1%, and the minimum cannot be less than 15%.

[0016] Among them, if the effective power base window that exceeds the emission limit exceeds the predetermined 10%, it is considered that the daily emission exceeds the standard.

[0017] The instantaneous emission mass of the gaseous pollutants is calculated according to the following formula:

[0018]

[0019] Where, NOx t is the instantaneous emission of gaseous pollutants; NOx conc is the instantaneous concentration of gaseous pollutants in the original exhaust gas; G exh is the instantaneous exhaust flow rate, which is obtained by subtracting the fuel flow rate from the intake flow rate.

[0020] The instantaneous power of the diesel engine is calculated based on the actual speed and torque value of the diesel engine, and then multiplied by the time interval. The calculation formula is as follows:

[0021]

[0022] Where W t is the instantaneous power of the diesel engine, T t is the instantaneous net torque, n t is the instantaneous speed.

[0023] The calculation window average power percentage is calculated using the following formula:

[0024]

[0025] Where, P max is the maximum net power of the diesel engine, AWP is the window average power percentage;

[0026] For the i-th work basis window, it satisfies:

[0027]

[0028] t 2,i Should meet

[0029] Where, t 1,i and t 2,i are the start time and end time of the i-th power basis window, W ref is the work done by the diesel engine in transient cycle NRT; Δt is the data sampling period.

[0030] Among them, the calculation of effective power base window ratio emission is calculated using the following formula:

[0031]

[0032] Where, EF gas Indicates the effective power basis window ratio emission.

[0033] The present invention is a calculation method for remote monitoring of emissions from non-road mobile machinery. It is based on the emission big data received by the remote monitoring platform. By establishing a remote monitoring model for verifying and calculating the emissions of networked machinery, it can monitor the emission levels of the machinery during its actual working process and accurately identify and enforce the law against machinery with excessive emissions. This meets the requirements of the ecological and environmental authorities for remote supervision of emissions from non-road mobile machinery and improves supervision efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a flow chart of the emission accounting method of the non-road mobile machinery operation process based on remote monitoring data of the present invention.

[0035] Figure 2 It is a schematic diagram of the effective data determination process of the present invention.

[0036] Figure 3 It is a schematic diagram of the effective window and window emission calculation of the present invention. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] The method of the present invention is applicable to the regulatory use of non-road mobile machinery that meets the fifth stage emission standard and is equipped with an SCR (selective catalytic reduction) post-treatment device.

[0039] like Figure 1 As shown, the method for calculating emissions during the operation of non-road mobile machinery based on remote monitoring data according to an embodiment of the present invention is implemented by the following steps:

[0040] Step 1. Data input;

[0041] Step 2. Invalid data determination;

[0042] Based on the data uploaded daily to the remote monitoring platform by non-road mobile machinery, data with invalid NOx values ​​are excluded. The following data among other data should be considered invalid:

[0043] A. Data where the engine power is less than 10% of the maximum net power;

[0044] B. Data corresponding to the cold engine state (cold start): when the coolant temperature of the diesel engine is lower than 70°C, and the coolant temperature changes by 2°C or more within 5 minutes, but not later than 20 minutes after the diesel engine is started;

[0045] C. Data when the ambient temperature is less than 10°C or greater than 38°C or the altitude exceeds 1700m.

[0046] Step 3. Valid data determination

[0047] Data other than invalid data determined according to the above principle (step 2) is considered valid data, and the duration is calculated for each data. According to the calculated duration, invalid data is divided into short invalid data (duration ≤ 600s) and long invalid data (duration > 600s).

[0048] The embodiment of the present invention further determines invalid data according to the following principles:

[0049] Step 3.1: Invalid data shorter than 120s is considered valid data;

[0050] Step 3.2: Valid data shorter than 120s is invalid data;

[0051] Step 3.3: The data from the startup phase after a long period of invalid data until the exhaust temperature reaches 250°C is also invalid. If the exhaust temperature does not reach 250°C within 240 seconds, the data after 240 seconds should be considered valid.

[0052] Step 3.4: The invalid data in the first 120 seconds after the end of the valid data is valid data.

[0053] Step 4. Calculation of emission results

[0054] The data included in the invalid data determined according to the above principles will not be included in the emission calculation, and only valid data can be used for calculation.

[0055] Step 4.1: Calculate the instantaneous emission mass of gaseous pollutants:

[0056] Instantaneous emission mass of gaseous pollutants NOx t(g / s) is calculated according to the following formula (assuming that the density of the exhaust gas at 273K (0℃) and 101.3kPa is 1.293kg / m 3 ):

[0057]

[0058] Where, NOx t is the instantaneous emission of each gaseous pollutant, in g·s -1 ; NOx conc (expressed in C1 equivalent) is the instantaneous wet basis concentration of each gaseous pollutant in the original exhaust gas, in ppm; G exh It is the instantaneous exhaust flow rate in kg / h, which can be obtained by subtracting the fuel flow rate from the intake flow rate.

[0059] Step 4.2: Calculate the instantaneous power of the diesel engine. Calculate the diesel engine output power based on the actual speed and torque value of the diesel engine, and multiply it by the time interval to obtain the instantaneous power of the diesel engine (unit: kWh).

[0060]

[0061] Where W t is the instantaneous power, in kWh; T t is the instantaneous net torque, in Nm; n t is the instantaneous speed, in r / min.

[0062] Step 4.3: Calculate the window average power percentage;

[0063] For the i-th work basis window

[0064] Where, t 2,i Should meet

[0065] Where, t 1,i and t 2,i are the start time and end time of the i-th power base window, in seconds; W ref is the diesel engine transient cycle (NRTC) work, in kWh; Δt is the data sampling period, generally 1 Hz.

[0066] Step 4.4: Calculate the window average power percentage:

[0067]

[0068] Where, P max It is the maximum net power of the diesel engine in kW.

[0069] Windows with an average window power percentage greater than 20% are effective power-base windows. If the number of windows with an average window power percentage greater than 20% is less than 50% of all windows, the requirement of 20% average window power percentage can be gradually reduced in steps of 1%, but the minimum cannot be less than 15%.

[0070] Step 4.5: Calculate the effective work basis window ratio emission:

[0071]

[0072] Count the number of windows in the effective power base window whose emissions meet the pollutant emission limits, and calculate their proportion to the total number of effective power base windows. If the proportion of effective power base windows exceeding the emission limits exceeds 10%, the daily emissions are considered to exceed the limit.

[0073] The method of the embodiment of the present invention can solve the "three difficulties" of non-road mobile machinery supervision, law enforcement, and evaluation, and fill the gap in the current remote supervision method of non-road mobile machinery emissions.

[0074] The method of the embodiment of the present invention is based on the emission data of networked machinery received by the remote monitoring platform, verifies whether the emission level of the calculated machinery meets the emission standard requirements and screens out machinery with excessive emissions, which can provide the ecological and environmental authorities with clues of illegal violations of non-road mobile machinery emissions exceeding the standard.

[0075] The basic principles, main features and advantages of the present invention are shown and described above. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0076] The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are therefore intended to be embraced therein.

[0077] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for calculating emissions from non-road mobile machinery operations based on remote monitoring data, characterized in that: The following steps are involved: Based on the invalid data determination program, the data with invalid NOx values ​​in the daily monitoring data uploaded to the remote monitoring platform by non-road mobile machinery are eliminated and invalid data is determined; Determine valid data based on valid data determination procedure; Calculate the emission results of valid data; first calculate the instantaneous emissions of gaseous pollutants and the instantaneous power of the diesel engine, then calculate the window average power percentage, determine the effective power base window based on the window average power percentage, calculate the effective power base window ratio emission, count the number of effective power base windows whose effective power base window ratio emissions meet the pollutant emission limit, and calculate the proportion of the total number of effective power base windows; if the proportion of effective power base windows that exceed the pollutant emission limit exceeds the predetermined threshold, it is considered that the daily emissions exceed the standard.

2. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1 is characterized in that: The invalid data includes: data where the engine power is less than 10% of the maximum net power; data corresponding to the engine cold state: the coolant temperature of the diesel engine is less than 70°C, and the coolant temperature changes by more than or equal to 2°C within 5 minutes, no later than 20 minutes after the diesel engine is started; data where the ambient temperature is less than 10°C or greater than 38°C or the altitude exceeds 1700m.

3. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1 is characterized in that: The invalid data is divided into short invalid data and long invalid data according to the duration; among them, invalid data shorter than 120s is valid data, and valid data shorter than 120s is invalid data; the startup phase after the long invalid data until the exhaust temperature reaches 250°C is invalid data. If the exhaust temperature does not reach 250°C within 240s, the data after 240s is regarded as valid data; the invalid data for 120s after the end of the valid data is valid data.

4. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1 is characterized in that: Windows with an average window power percentage greater than 20% are valid power-base windows. If the number of windows with an average window power percentage greater than 20% is less than 50% of the total number of windows, the 20% requirement for the average window power percentage will be gradually reduced in steps of 1%, and the minimum requirement cannot be less than 15%.

5. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1 is characterized in that: If the effective power base window that exceeds the emission limit exceeds the predetermined 10%, the daily emission is considered to be in excess of the limit.

6. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1, characterized in that: The instantaneous emission of gaseous pollutants is calculated according to the following formula: Where, NOx t is the instantaneous emission of gaseous pollutants; NOx conc is the instantaneous concentration of gaseous pollutants in the original exhaust gas; G exh is the instantaneous exhaust flow rate, which is obtained by subtracting the fuel flow rate from the intake flow rate.

7. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 1, characterized in that: The instantaneous power of the diesel engine is obtained by calculating the output power of the diesel engine based on the actual speed and torque value of the diesel engine and multiplying it by the time interval; The calculation formula is as follows; Where W t is the instantaneous power of the diesel engine, T t is the instantaneous net torque, n t is the instantaneous speed.

8. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 7 is characterized in that: The average power percentage of the calculation window is calculated using the following formula: Where, P max is the maximum net power of the diesel engine, AWP is the window average power percentage; For the i-th work basis window, it satisfies: t 2,i Should meet Where, t 1,i and t 2,i are the start time and end time of the i-th power basis window, W ref is the transient cycle work of the diesel engine; Δt is the data sampling period.

9. The method for calculating emissions during non-road mobile machinery operations based on remote monitoring data according to claim 8, characterized in that: The effective power base window ratio emission is calculated using the following formula: Where, EF NOx Indicates the effective power basis window ratio emission.

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