Portable gas chromatograph mine harmful gas detection system and method

Abstract

The invention relates to the technical field of gas detection, and discloses a portable gas chromatograph mine harmful gas detection system and method, the system comprises a chromatographic data processing module, a signal feature extraction module, a chromatographic signal difference module, a dual-channel construction module, a working curve construction module and a harmful gas concentration acquisition module, collecting original chromatographic data, and removing baseline drift and random noise to obtain standard chromatographic data; identifying a baseline interval, inserting signal features according to the time sequence position to obtain a dynamic baseline signal, and performing differential analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal; selecting a background gas chromatographic peak as an internal reference channel, and taking a preset standard gas response factor as an external reference channel; correcting the response factor of the target harmful gas so as to evolve into a real-time quantitative working curve and obtain harmful gas concentration information; the mine harmful gas detection accuracy can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas detection, and in particular to a portable gas chromatograph mine harmful gas detection system and method. BACKGROUND

[0002] Mine harmful gas detection is the core link to ensure the safety of mining operations. Portable gas chromatographs have become the mainstream detection equipment due to their mobility advantages. However, the existing technology has obvious defects in the data preprocessing stage. The baseline drift and random noise suppression effect in the original chromatographic data is limited, and there is a lack of targeted segmented processing strategy, resulting in abnormal discrete points in the smoothed signal, which cannot form stable and unified standard chromatographic data, directly affecting the accuracy of subsequent signal feature recognition, and making it difficult to provide reliable data basis for harmful gas concentration analysis.

[0003] In the process of harmful gas quantitative analysis, the detection logic of the existing technology has shortcomings. On the one hand, the reference channel design is not perfect, and the characteristics of the background gas are not fully utilized for interference compensation, resulting in a lack of scientific basis for the response factor correction of the target harmful gas. On the other hand, the construction of dynamic baseline signal and the difference analysis method are unreasonable, which easily leaves low-frequency interference and high-frequency burrs, resulting in insufficient purity of the net chromatographic signal. These two problems together result in poor adaptability of the real-time quantitative working curve, and there is a large error in the mapping relationship between peak area and concentration, ultimately causing insufficient precision of harmful gas concentration detection results, and failing to meet the strict requirements of mine operations on detection reliability. Therefore, how to improve the accuracy of harmful gas concentration detection has become a problem to be solved. SUMMARY

[0004] The present application provides a portable gas chromatograph mine harmful gas detection system and method to solve the problems raised in the background technology.

[0005] To achieve the above purpose, the present application provides a portable gas chromatograph mine harmful gas detection system, characterized in that the system comprises a chromatographic data processing module, a signal feature extraction module, a chromatographic signal difference module, a double-channel construction module, a working curve construction module and a harmful gas concentration acquisition module, wherein: The chromatographic data processing module is used to collect gas samples in the mine by a portable gas chromatograph, obtain the original chromatographic data of the mine, and remove the baseline drift and random noise in the original chromatographic data to obtain the standard chromatographic data of the mine. The signal feature extraction module is used to identify the baseline interval in the standard chromatographic data that does not contain the target harmful gas chromatographic peak, and extract the signal features of the baseline interval. a chromatographic signal difference module configured to insert the signal feature according to the time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and to perform difference analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine; a double-channel construction module configured to select a background gas chromatographic peak in the net chromatographic signal as an internal reference channel of the mine, to obtain peak area measured data of the background gas chromatographic peak, and to use a preset standard gas response factor as an external reference channel of the mine; a working curve construction module configured to correct a response factor of a target harmful gas in the external reference channel according to the peak area measured data, and to evolve the corrected response factor into a real-time quantitative working curve of the mine; a harmful gas concentration obtaining module configured to map a peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain harmful gas concentration information of the mine.

[0006] In a preferred embodiment, when the chromatographic data processing module performs removal of baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine, it is specifically configured to: divide the original chromatographic data into a chromatographic peak signal segment and a baseline noise segment according to signal amplitude and change rate of the original chromatographic data of the mine; suppress high-frequency random fluctuations in the baseline noise segment to obtain a smoothed baseline segment of the mine; filter out burr noise in the chromatographic peak signal segment while keeping the basic outline of the peak type unchanged to obtain a smoothed chromatographic peak segment of the mine; connect the smoothed baseline segment and the smoothed chromatographic peak segment in time sequence, and correct abnormal discrete points in the spliced signal data to obtain the standard chromatographic data of the mine.

[0007] In a preferred embodiment, when the signal feature extraction performs identification of a baseline interval in the standard chromatographic data that does not contain a target harmful gas chromatographic peak, and extraction of a signal feature of the baseline interval, it is specifically configured to: identify a continuous time segment in which the signal change amplitude of the standard chromatographic data continuously remains below a standard threshold value in the standard chromatographic data to obtain an initial candidate interval of the standard chromatographic data; evaluate consistency of signal patterns in the initial candidate interval to obtain a smooth baseline interval of the mine; perform comparison and analysis of time information in the smooth baseline interval and a retention time spectrum of a target harmful gas in the mine to obtain a candidate baseline interval of the mine; verify the concentration of signal distribution in the candidate baseline interval, to obtain the baseline interval of the mine; perform multi-dimensional analysis on the baseline interval to obtain the signal characteristics of the baseline interval.

[0008] In a preferred embodiment, when the chromatographic signal difference module inserts the signal characteristics according to the time sequence position of the baseline interval to obtain the dynamic baseline signal of the mine, and performs difference analysis on the standard chromatographic data and the dynamic baseline signal to obtain the net chromatographic signal of the mine, specifically for: establish the control signal sequence of the mine with the center time point of the baseline interval as the time reference and the horizontal reference signal in the signal characteristics as the amplitude reference; extend the control signal sequence in the global time range of the standard chromatographic data, and add reference constraint signals at the beginning and end of the global time range to obtain the complete constraint signal set of the standard chromatographic data; time-align the complete constraint signal set with the standard chromatographic data to obtain the dynamic baseline signal of the standard chromatographic data; eliminate the dynamic baseline signal from the standard chromatographic data to obtain the initial difference signal of the mine; compensate for low-frequency residues in the initial difference signal and smooth high-frequency burrs in the initial difference signal to obtain the net chromatographic signal of the mine.

[0009] In a preferred embodiment, when the dual-channel construction module selects the background gas chromatographic peak in the net chromatographic signal as the internal reference channel of the mine to obtain the peak area measured data of the background gas chromatographic peak, specifically for: monitor the chromatographic peak of the net chromatographic signal, and select the chromatographic peak with regular peak shape and stable broadening as the candidate background gas chromatographic peak of the mine; interval match the retention time of the candidate background gas chromatographic peak with the retention time spectrum of the inherent background gas in the mine to obtain the stable background gas chromatographic peak of the mine; analyze the purity of the stable background gas chromatographic peak, and select the background gas chromatographic peak with single purity as the internal reference channel of the mine; determine the background baseline of the mine according to the peak start point and the peak end point of the background gas chromatographic peak; calculate the peak area measured data of the background gas chromatographic peak according to the background baseline.

[0010] In a preferred embodiment, the calculation formula of the peak area measured data is: ; wherein, represents the peak area measured data of the background gas chromatographic peak, represents the peak height of the background gas chromatographic peak, represents the peak width of the background gas chromatographic peak at a preset proportion height, represents the peak vertex time value of the background gas chromatographic peak, represents the peak start time value of the background gas chromatographic peak, represents the peak end time value of the background gas chromatographic peak, represents a preset peak shape mixing factor, represents an integral function, represents an exponential function, represents a circular constant.

[0011] In a preferred embodiment, the working curve construction module, when performing correction of the response factor of the target harmful gas in the external reference channel according to the peak area measured data, is specifically used for: taking the proportional relationship between the peak area measured data and the standard peak area of the background gas chromatographic peak in the mine as a background interference compensation parameter of the mine; associating the background interference compensation parameter and the response factor of the target harmful gas in the external reference channel to obtain an associated response factor of the target harmful gas; converging the associated response factor according to the distribution characteristics of the background interference compensation parameter to obtain a corrected response factor of the target harmful gas.

[0012] In a preferred embodiment, the working curve construction module, when performing evolution of the corrected response factor into a real-time quantitative working curve of the mine, is specifically used for: constructing a two-dimensional coordinate system of the target harmful gas with the chromatographic peak area of the target harmful gas as the horizontal axis and the gas concentration of the target harmful gas as the vertical axis; mapping the corrected response factor into the two-dimensional coordinate system to construct a concentration basic curve of the target harmful gas; adjusting the slope of the concentration basic curve according to the signal stability index of the net chromatographic signal in the mine to obtain an optimized concentration curve of the target harmful gas; mapping the environmental parameters of the mine and the real-time state parameters of the portable gas chromatograph into boundary constraint conditions of the optimized concentration curve; continuously verifying the optimized concentration curve under the boundary constraint conditions to obtain a real-time quantitative working curve of the mine.

[0013] In a preferred implementation, the harmful gas concentration acquisition module, when performing mapping of the peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain the harmful gas concentration information of the mine, is specifically configured to: point-by-point match the peak area of the target harmful gas chromatographic peak with the real-time quantitative working curve to obtain an initial concentration point of the peak area; verify the reliability of the initial concentration point according to the noise level of the net chromatographic signal and the curvature feature of the real-time quantitative working curve to obtain an effective concentration point of the peak area; based on the distribution of adjacent points on the real-time quantitative working curve, interpolate and correct the effective concentration point to obtain the harmful gas concentration information of the mine.

[0014] To solve the above problems, the application further provides a portable gas chromatograph mine harmful gas detection method, which comprises: S1, collecting a gas sample in a mine by a portable gas chromatograph to obtain original chromatographic data of the mine, and removing baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine; S2, identifying a baseline interval containing no target harmful gas chromatographic peak in the standard chromatographic data, and extracting a signal feature of the baseline interval; S3, inserting the signal feature according to the time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and performing differential analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine; S4, selecting a background gas chromatographic peak in the net chromatographic signal as an internal reference channel of the mine to obtain peak area measured data of the background gas chromatographic peak, and taking a preset standard gas response factor as an external reference channel of the mine; S5, correcting the response factor of a target harmful gas in the external reference channel according to the peak area measured data, and evolving the corrected response factor into a real-time quantitative working curve of the mine; S6, mapping the peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain harmful gas concentration information of the mine.

[0015] Compared with the prior art, the application has the following beneficial effects: 1. The present application effectively removes baseline drift and random noise in the original data through a fine chromatographic data processing flow, extracts and constructs dynamic baseline signals based on the signal characteristics of the baseline interval, obtains high-purity net chromatographic signals through differential analysis, significantly improves the accuracy of target harmful gas chromatographic peak recognition, provides reliable data support for concentration calculation, and ensures the authenticity and effectiveness of harmful gas concentration information.

[0016] 2. The present application uses peak area measurement data to correct the response factor and evolve real-time quantitative working curves, and combines with subsequent interpolation correction and other optimization steps, which greatly improves the timeliness and stability of harmful gas concentration detection, and can quickly output accurate concentration information, providing efficient and reliable technical support for mine harmful gas prevention and control. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The system architecture diagram of a portable gas chromatograph mine harmful gas detection system provided by an embodiment of the present application is provided. Figure 2 The flowchart of a portable gas chromatograph mine harmful gas detection method provided by an embodiment of the present application is provided.

[0018] The implementation, functional characteristics and advantages of the present application will be further described with reference to the drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme of the embodiments of the present application will be described clearly and completely in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiments belong to part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates otherwise. "Multiple" generally includes at least two.

[0021] Depending on context, the word "if" or "if" can be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting", as the case can be. Similarly, the phrase "if determined" or "if [a stated condition or event] is detected" can be interpreted to mean "when determined" or "in response to determining" or "when [stated condition or event] is detected" or "in response to detecting [stated condition or event]", as the case can be.

[0022] In addition, the step sequence in each of the following method embodiments is only an example, and is not strictly limited.

[0023] In fact, the server device deployed by the portable gas chromatograph mine harmful gas detection system can be composed of one or more devices. The portable gas chromatograph mine harmful gas detection system can be implemented as a business instance, a virtual machine, or a hardware device. For example, the portable gas chromatograph mine harmful gas detection system can be implemented as a business instance deployed on one or more devices in a cloud node. In short, the portable gas chromatograph mine harmful gas detection system can be understood as a software deployed on a cloud node, which is used to provide a portable gas chromatograph mine harmful gas detection system for each user terminal. Alternatively, the portable gas chromatograph mine harmful gas detection system can also be implemented as a virtual machine deployed on one or more devices in a cloud node. The virtual machine has application software installed for managing each user terminal. Alternatively, the portable gas chromatograph mine harmful gas detection system can also be implemented as a server composed of a plurality of same or different types of hardware devices, and one or more hardware devices are provided to provide a portable gas chromatograph mine harmful gas detection system for each user terminal.

[0024] In terms of implementation, the portable gas chromatograph mine harmful gas detection system and the user terminal are mutually adapted. That is, the portable gas chromatograph mine harmful gas detection system is an application installed on a cloud service platform, and the user terminal is a client that establishes a communication connection with the application; or the portable gas chromatograph mine harmful gas detection system is implemented as a website, and the user terminal is implemented as a webpage; or the portable gas chromatograph mine harmful gas detection system is implemented as a cloud service platform, and the user terminal is implemented as an applet in an instant messaging application.

[0025] As Figure 1 shown is a system architecture diagram of a portable gas chromatograph mine harmful gas detection system according to an embodiment of the present application.

[0026] The portable gas chromatograph mine harmful gas detection system 100 can be arranged in a cloud server, and in a realization form, can be used as one or more service devices, can be installed on a cloud as an application (for example, a server of a mobile service operator, a server cluster, etc.), or can be developed as a website. According to a function realized, the portable gas chromatograph mine harmful gas detection system 100 can include a chromatographic data processing module 101, a signal feature extraction module 102, a chromatographic signal difference module 103, a double-channel construction module 104, a working curve construction module 105, and a harmful gas concentration acquisition module 106. The modules in the present application can also be referred to as units, which refer to a series of computer program segments capable of being executed by an electronic device processor and capable of completing a fixed function, and are stored in a memory of the electronic device.

[0027] In the embodiment of the present application, each of the above modules can be independently realized and called by other modules. The calling here can be understood as that a module can be connected to multiple modules of another type and provide corresponding services for the connected multiple modules. The portable gas chromatograph mine harmful gas detection system provided in the embodiment of the present application can adjust the application range of the portable gas chromatograph mine harmful gas detection system architecture by increasing modules and directly calling without modifying program codes, realize cluster-type horizontal expansion, so as to achieve the purpose of quickly and flexibly expanding the portable gas chromatograph mine harmful gas detection system. In actual application, the above modules can be arranged in the same device or different devices, or can be arranged in a virtual device, for example, a service instance in a cloud server.

[0028] The following will be described in combination with specific embodiments, respectively for each component and specific working process of the portable gas chromatograph mine harmful gas detection system: The chromatographic data processing module 101 is used to collect gas samples in a mine by a portable gas chromatograph, obtain original chromatographic data of the mine, and remove baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine. In the embodiment of the present application, when the chromatographic data processing module removes the baseline drift and random noise in the original chromatographic data to obtain the standard chromatographic data of the mine, it is specifically used for: According to a signal amplitude and a change rate of the original chromatographic data in the mine, the original chromatographic data is divided into a chromatographic peak signal segment and a baseline noise segment; Inhibiting high-frequency random fluctuations in the baseline noise segment to obtain a smooth baseline segment of the mine; In the premise of keeping the basic profile of the peak type in the chromatographic peak signal segment unchanged, the burr noise of the chromatographic peak signal segment is filtered out to obtain the smooth chromatographic peak segment of the mine; In time sequence, the smooth baseline segment and the smooth chromatographic peak segment are connected, and abnormal discrete points in the spliced signal data are corrected to obtain the standard chromatographic data of the mine.

[0029] The signal amplitude corresponding to each time point of the original chromatographic data in the mine is observed, and the change rate of the signal amplitude between adjacent two time points is calculated. Through comparative analysis, the continuous time segment with the signal amplitude obviously higher than the average level of the surrounding area and the change rate exceeding the common stable fluctuation range of the mine chromatographic data is determined as the chromatographic peak signal segment. The continuous time segment with the lower signal amplitude, the smaller change rate and the stable retention is determined as the baseline noise segment, so as to complete the division of the original chromatographic data into the chromatographic peak signal segment and the baseline noise segment.

[0030] The baseline noise segment is processed by using the moving average method. The signal amplitudes corresponding to a plurality of continuous time points in the baseline noise segment are selected as a processing group, the average value of all signal amplitudes in the processing group is calculated, and the average value is used to replace the original signal amplitude of the middle time point in the processing group. Then, the processing group is moved in time sequence, and the same processing is performed on the signal amplitudes of all time points in the baseline noise segment one by one, so as to weaken the sudden high-frequency fluctuation of the signal amplitude in the baseline noise segment. Finally, the smooth baseline segment of the mine with stable signal amplitude change is obtained.

[0031] First, the vertex position, the starting position and the ending position of each chromatographic peak in the chromatographic peak signal segment are identified to clearly define the basic profile range of each chromatographic peak. In the range, a single or continuous small signal point with the signal amplitude suddenly deviating from the amplitudes of adjacent signal points and the deviation degree exceeding the normal fluctuation range in the peak is found. These points are burr noise. The intermediate value of the amplitudes of adjacent normal signal points before and after the burr noise is taken as the intermediate value of the amplitudes of the adjacent normal signal points, and the intermediate value is used to replace the amplitude of the signal point corresponding to the burr noise. In the replacement process, the vertex amplitude, the overall width of the peak and the change trend of the rising edge and the falling edge of the peak are strictly kept unchanged, so as to filter out the burr noise in the premise of keeping the basic profile of the peak type in the chromatographic peak signal segment unchanged, and obtain the smooth chromatographic peak segment of the mine.

[0032] According to the time sequence of the original chromatographic data, the last time point of the smooth baseline segment and the first time point of the smooth chromatographic peak segment adjacent to the last time point are found, the signal amplitudes corresponding to the two time points are connected, the signal amplitude at the connection position is naturally connected from the amplitude of the smooth baseline segment to the amplitude of the smooth chromatographic peak segment, so that the signal amplitude jump is avoided, after the connection, the entire spliced signal data is traversed, the points with the signal amplitude deviating greatly compared with the signal amplitudes of the adjacent time points and not conforming to the normal change trend of the signal are found, these points are abnormal discrete points, for each abnormal discrete point, the amplitude change law of the normal signal points before and after the abnormal discrete point is analyzed, a reasonable amplitude conforming to the overall change trend is calculated according to the law, and the original amplitude of the abnormal discrete point is replaced with the reasonable amplitude, after the connection and the smoothing of the baseline segment and the chromatographic peak segment and the correction of the abnormal discrete points in the spliced signal data, the standard chromatographic data of the mine are finally obtained.

[0033] The implementation process can accurately divide the original chromatographic data into chromatographic peak signal segments and baseline noise segments, ensure that the subsequent processing is highly targeted, obtain a smooth baseline segment when suppressing high-frequency random fluctuations in the baseline noise segment, and completely retain the basic outline of the peak type when filtering out burr noise in the chromatographic peak signal segment, and finally obtain accurate and reliable standard chromatographic data of the mine by connecting the baseline segment and the chromatographic peak segment in time sequence and smoothing and correcting abnormal discrete points, thereby providing high-quality data support for subsequent related component analysis, safety monitoring and other work of the mine, and effectively avoiding the interference of noise and abnormal points on the data analysis result.

[0034] The signal feature extraction module 102 is configured to identify a baseline interval without a chromatographic peak of a target harmful gas in the standard chromatographic data, and extract a signal feature of the baseline interval. In the embodiment of the present application, when the signal feature extraction is performed to identify a baseline interval without a chromatographic peak of a target harmful gas in the standard chromatographic data, and extract a signal feature of the baseline interval, the signal feature extraction is specifically configured to: identify a continuous time period in which the signal change amplitude of the standard chromatographic data is continuously lower than a standard threshold value in the standard chromatographic data, to obtain an initial candidate interval of the standard chromatographic data; evaluate the consistency of the signal form in the initial candidate interval, to obtain a smooth baseline interval of the mine; perform comparison and analysis on the time information in the smooth baseline interval and the retention time spectrum of the target harmful gas in the mine, to obtain a candidate baseline interval of the mine; verify the concentration degree of the signal distribution in the candidate baseline interval, to obtain a baseline interval of the mine; perform multi-dimensional analysis on the baseline interval, to obtain a signal feature of the baseline interval.

[0035] The signal amplitude difference between two adjacent time points is calculated, and the difference is taken as the signal change amplitude. Meanwhile, the preset standard threshold in the standard chromatogram data is called, and the continuous time period of the standard chromatogram data is checked in sections. It is judged whether the signal change amplitudes of all time points in each continuous time period are lower than the standard threshold, and the state of being lower than the threshold needs to meet the preset time length requirement. After the section-by-section screening, the continuous time period meeting the condition of "signal change amplitude continuously lower than the standard threshold" is determined, and the initial candidate interval of the standard chromatogram data is obtained.

[0036] For each initial candidate interval, the amplitude data of all signal points in the interval is extracted, the difference between the maximum and minimum signal amplitudes in the interval is calculated to measure the fluctuation range of the signal in the interval, and the overall change trend of the signal in the interval is observed to determine whether there is a sudden rise, fall or irregular fluctuation. If the fluctuation range of the signal amplitude in a certain initial candidate interval is controlled within a very small preset range, and there is no obvious abnormal fluctuation and stable change trend, it is determined that the signal form of the interval has consistency. Through the one-by-one evaluation of all initial candidate intervals, the interval meeting the signal form consistency requirement is screened out, and the stable baseline interval of the mine is obtained.

[0037] First, the start time and end time of each interval are extracted from the recorded data of the stable baseline interval to form the complete time information of the interval. Then, the retention time spectrum of the target harmful gas in the mine is called, which contains the specific time range of the chromatographic peak of each target harmful gas in the chromatographic analysis. The start time and end time of the stable baseline interval are compared with the peak time range of each target harmful gas in the retention time spectrum. If the time range of a certain stable baseline interval does not overlap with the peak time range of any target harmful gas in the retention time spectrum, and is completely in the non-peak time range, the stable baseline interval is determined as the candidate baseline interval of the mine.

[0038] For each candidate baseline interval, the amplitude data of all signal points in the interval is collected, the number of amplitude intervals in which the amplitude data falls is counted, and the amplitude interval with the largest number and the proportion of the number of signal points it contains to the total number of signal points in the candidate baseline interval are calculated. At the same time, the average value and variance of all signal amplitudes in the candidate baseline interval are calculated. If the proportion of signal points in the amplitude interval with the largest number exceeds the preset proportion threshold, and the variance is within the preset small variance range, it means that the signal amplitudes in the candidate baseline interval are mainly concentrated in a certain range, and the signal distribution has a high concentration. Through the verification of the signal distribution concentration of all candidate baseline intervals, the baseline interval of the mine meeting the requirements is finally determined.

[0039] The baseline interval is analyzed from multiple dimensions. Firstly, the time dimension feature of the baseline interval is extracted, the start time, end time and duration obtained by the difference between the start time and end time of the baseline interval are calculated; secondly, the signal amplitude dimension feature is extracted, the average value of all signal amplitudes in the baseline interval, the median value and the difference between the maximum value and the minimum value are calculated to obtain the fluctuation range; finally, the signal stability dimension feature is extracted, the standard deviation of the signal amplitude in the baseline interval is calculated, and the signal features of the baseline interval are integrated by collecting and calculating the information of the three dimensions of time, signal amplitude and signal stability.

[0040] The beneficial effect is that the signal feature extraction implementation process accurately identifies the baseline interval without the target harmful gas chromatographic peak from the standard chromatographic data through multi-step screening, first screens the initial candidate interval through the signal change amplitude, then gradually optimizes through signal morphology consistency evaluation, time comparison analysis and signal distribution concentration verification, ensures that the final obtained baseline interval is accurate and reliable, and the subsequent multi-dimensional analysis of the baseline interval can comprehensively obtain the signal features, provides a pure baseline reference for the subsequent accurate detection of the target harmful gas, effectively avoids the interference of non-target signals on the detection result, and improves the accuracy and stability of the mine harmful gas detection.

[0041] The chromatographic signal difference module 103 is configured to insert the signal feature according to the time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and perform difference analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine. In the embodiment of the present application, when the chromatographic signal difference module performs difference analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine, it is specifically used for: Taking the center time point of the baseline interval as a time reference and taking the horizontal reference signal in the signal feature as an amplitude reference, a control signal sequence of the mine is established. The control signal sequence is expanded in the global time range of the standard chromatographic data, and reference constraint signals are added at the start point and the end point of the global time range to obtain a complete constraint signal set of the standard chromatographic data. The complete constraint signal set is time-aligned with the standard chromatographic data to obtain a dynamic baseline signal of the standard chromatographic data. The dynamic baseline signal is removed from the standard chromatographic data to obtain an initial difference signal of the mine. Low-frequency residues in the initial difference signal are compensated, and high-frequency burrs in the initial difference signal are smoothed to obtain a net chromatographic signal of the mine.

[0042] First, the starting time and the ending time of each baseline interval are extracted from the record of the baseline interval, the starting time is added to the ending time and then divided by two, and the center time point of each baseline interval is calculated, which is taken as the time reference for establishing the control signal sequence, and the level reference signal is retrieved from the previously extracted baseline interval signal features, which is the average of the signal amplitude in the baseline interval. Taking the center time point as the core node, the level reference signal is assigned to the center time point as the corresponding amplitude, and then according to the signal stability characteristics of the baseline interval, the signal amplitudes of the adjacent time points before and after the center time point are kept consistent with the level reference signal, forming a stable amplitude signal sequence, which is the control signal sequence of the mine.

[0043] First, the global time range of the standard chromatographic data is determined, that is, the entire time region covered by the starting time to the ending time of the standard chromatographic data, and the established control signal sequence is extended to the starting end and the ending end of the global time range. During the extension process, the signal amplitude is kept consistent with the amplitude of the control signal sequence. After the extension covers the global time range, an additional signal point is added before the starting point of the global time range as a reference constraint signal, and the amplitude of the signal point is the same as the signal amplitude of the starting point of the global time range. At the same time, an additional signal point is added after the terminal point of the global time range as a reference constraint signal, and the amplitude of the signal point is the same as the signal amplitude of the terminal point of the global time range. Integrating the extended control signal sequence and the two newly added reference constraint signals, the complete constraint signal set of the standard chromatographic data is obtained.

[0044] The time information and the corresponding amplitude information of each signal point in the complete constraint signal set are extracted, and the time information and the amplitude information of each data point in the standard chromatographic data are extracted. Taking the time information as the matching basis, each signal point in the complete constraint signal set is matched with the data point of the same time in the standard chromatographic data one by one, so that the time axis of the complete constraint signal set completely coincides with the time axis of the standard chromatographic data. After the matching is completed, the complete constraint signal set becomes a signal that is completely consistent with the time sequence of the standard chromatographic data, which is the dynamic baseline signal of the standard chromatographic data.

[0045] The signal amplitude corresponding to each time point in the standard chromatographic data is extracted one by one, and the signal amplitude corresponding to the same time point in the dynamic baseline signal is extracted. The difference amplitude of the time point is obtained by subtracting the signal amplitude of the same time point in the dynamic baseline signal from the signal amplitude of the time point in the standard chromatographic data. According to the time sequence, all the time points are arranged in order to form a continuous signal, which is the initial difference signal of the mine.

[0046] The initial differential signal is observed in sections to determine whether there is a low-frequency residual trend of overall slow rise or slow decline, if the trend exists, the average change rate of the low-frequency residual trend is calculated, and the amplitude of each time point in the initial differential signal is adjusted in the opposite direction according to the average change rate, that is, if the trend is rising, each time point is subtracted by the corresponding rising amplitude, and if it is falling, each time point is added by the corresponding falling amplitude, so as to compensate the low-frequency residual in the initial differential signal, then the high-frequency burr point of the initial differential signal is found, which is suddenly deviated from the amplitudes of adjacent signal points, the amplitudes of the two adjacent normal signal points before and after the burr point are referred to, the average value of these adjacent normal signal points is calculated, and the average value is used to replace the amplitude of the burr point, so as to complete the smoothing processing of the high-frequency burr, and finally the net chromatogram signal of the mine is obtained.

[0047] The beneficial effect is that the implementation process first establishes a control signal sequence with key parameters in the baseline interval, obtains a complete constraint signal set through expansion and addition of constraint signals, accurately generates a dynamic baseline signal through time alignment, and then obtains a net chromatogram signal through difference, low-frequency residual compensation and high-frequency burr smoothing processing. The whole process effectively removes the baseline interference in the standard chromatogram data, retains the complete information of the target signal, makes the net chromatogram signal purer, provides a high-quality signal basis for subsequent accurate identification and quantitative analysis of harmful gases in the mine, and improves the reliability and accuracy of detection.

[0048] The double-channel construction module 104 is configured to select a background gas chromatographic peak in the net chromatogram signal as an internal reference channel of the mine, to obtain peak area measured data of the background gas chromatographic peak, and to use a preset standard gas response factor as an external reference channel of the mine. In the embodiment of the present application, when the double-channel construction module selects a background gas chromatographic peak in the net chromatogram signal as an internal reference channel of the mine to obtain peak area measured data of the background gas chromatographic peak, it is specifically configured to: Monitor the chromatographic peaks of the net chromatogram signal, and select a chromatographic peak with regular peak shape and stable peak broadening from the chromatographic peaks as a candidate background gas chromatographic peak of the mine. Interval match the retention time of the candidate background gas chromatographic peak with the retention time spectrum of the inherent background gas in the mine, to obtain a stable background gas chromatographic peak of the mine. Analyze the purity of the stable background gas chromatographic peak, and select a background gas chromatographic peak with single purity as the internal reference channel of the mine. Determine the background baseline of the mine according to the peak start point and the peak end point of the background gas chromatographic peak. Calculate the peak area measured data of the background gas chromatographic peak according to the background baseline.

[0049] The calculation formula of the peak area measured data is: wherein, represents the peak area measured data, represents the peak height of the background gas chromatographic peak, represents the peak width of the background gas chromatographic peak at a preset proportion height, represents the peak vertex time value of the background gas chromatographic peak, represents the peak starting time value of the background gas chromatographic peak, represents the peak ending time value of the background gas chromatographic peak, represents a preset peak shape mixing factor, represents an integral function, represents an exponential function, represents a circular constant.

[0050] The signal amplitude changes of each time point in the net chromatographic signal are observed, and the parts with signal amplitudes obviously higher than the surrounding baseline and forming convex shapes are identified. These convex parts are the chromatographic peaks of the net chromatographic signal. Then, the peak shape of each chromatographic peak is checked one by one to determine whether the rising edge and the falling edge of the peak are symmetrical, without obvious distortion or deformation. At the same time, the width of the chromatographic peak at different horizontal positions on both sides of the peak vertex is measured to confirm that the peak width remains consistent and does not suddenly widen or narrow within the entire peak range. After screening the regularity of the peak shape and the stability of the peak width of all the chromatographic peaks, the chromatographic peaks meeting the conditions are determined as the candidate background gas chromatographic peaks of the mine.

[0051] The time corresponding to the vertex of each candidate background gas chromatographic peak is extracted, which is the retention time of the candidate background gas chromatographic peak. At the same time, the retention time spectrum of the inherent background gas in the mine is called, which records the respective peak time ranges of the common inherent background gases in the mine in chromatographic analysis. The retention time of each candidate background gas chromatographic peak is compared with the peak time range of each inherent background gas in the retention time spectrum. If the retention time of the candidate background gas chromatographic peak completely falls within the peak time range of a certain inherent background gas, and the coincidence degree meets the preset requirement, the candidate background gas chromatographic peak is determined as the stable background gas chromatographic peak of the mine.

[0052] ​The signal shape of the peak is checked point by point from the start point of the peak to the end point of the peak, whether the profile of the peak only has one obvious vertex, and whether additional small protrusions, shoulder peaks or signal fluctuations appear in the rising and falling edges of the peak, if the peak only has a single peak structure in the whole range, and no other impurity peaks or interference peaks are superimposed on the peak, it is determined that the purity of the stable background gas chromatographic peak is single, and the stable background gas chromatographic peak with single purity is selected as the internal reference channel of the mine.

[0053] For the background gas chromatographic peak as the internal reference channel, from the rising edge of the peak, the time point when the signal amplitude first exceeds the average amplitude of the baseline around the peak by a certain small amplitude is found, which is the start point of the background gas chromatographic peak, and from the falling edge of the peak, the time point when the signal amplitude first falls below the average amplitude of the baseline around the peak by a certain small amplitude is found, which is the end point of the background gas chromatographic peak, then connecting the signal amplitude points corresponding to the start point and the end point of the peak on the baseline forms a smooth straight line or curve, which is the background baseline of the mine.

[0054] With the determined background baseline as the reference, the time interval from the start point to the end point of the background gas chromatographic peak is determined as the range for calculating the peak area, in the time interval, the difference between the signal amplitude of each time point of the background gas chromatographic peak and the signal amplitude of the corresponding time point of the background baseline is obtained point by point, which is the effective peak height of each time point, the time interval between all adjacent time points in the time interval is taken as the calculation unit, the effective peak height of each adjacent time point is regarded as the two bases of the trapezoidal area, and the time interval is regarded as the height of the trapezoidal area, the area of each small trapezoidal area is calculated and the areas of all small trapezoidal areas are added, the total area calculated by this method is the measured data of the peak area of the background gas chromatographic peak.

[0055] The detection data of the background gas is obtained by chromatographic detection, the highest value of the chromatographic peak is found by analyzing the data, and the value corresponding to the peak height of the background gas chromatographic peak is obtained; a fixed proportion value is set, the peak height position corresponding to the proportion in the chromatographic detection data of the background gas is found, and the time difference value corresponding to the left and right sides of the position is measured, which is the value corresponding to the peak width of the background gas chromatographic peak at the preset proportion height; the chromatographic detection data of the background gas is analyzed to find the time point corresponding to the highest value of the chromatographic peak, which is the value corresponding to the peak top time value of the background gas chromatographic peak; the chromatographic detection data of the background gas is continuously analyzed, and when the detection signal value significantly rises from the baseline and reaches the preset start point judgment threshold, the corresponding time point is the value corresponding to the peak start point time value of the background gas chromatographic peak; the chromatographic detection data of the background gas is continuously analyzed, and when the chromatographic peak signal value decreases to the baseline level and meets the preset stop point judgment condition, the corresponding time point is the value corresponding to the peak stop point time value of the background gas chromatographic peak; according to the known characteristics of the background gas, the chromatographic detection experimental conditions and the statistical results of the historical detection data, a fixed value is set in advance to adjust the weight proportion of the two peak shape functions, which is the value corresponding to the preset peak shape mixing factor.

[0056] The time point corresponding to the peak start point time value is taken as the starting point of integration, and the time point corresponding to the peak stop point time value is taken as the end point of integration. In the time interval, the square root of pi is first calculated and multiplied by 2, and then the result is multiplied by the value corresponding to the peak height of the background gas chromatographic peak to obtain the basic coefficient; the difference between the time variable and the value corresponding to the peak top time value is calculated, the square of the difference is divided by the square of the value corresponding to the peak width of the background gas chromatographic peak at the preset proportion height, the inverse of the result is calculated, and then the result is multiplied by the value corresponding to the preset peak shape mixing factor to obtain the first function result; the difference between the time variable and the value corresponding to the peak top time value is calculated, the result is divided by the value corresponding to the peak width of the background gas chromatographic peak at the preset proportion height, and then the square of the result is added to 1, the result is divided by the addition result, and then the result is multiplied by the result of 1 minus the value corresponding to the preset peak shape mixing factor to obtain the second function result; the two function results are added to obtain the comprehensive function value, the integration time interval is divided into infinite small time elements, the product of the comprehensive function value corresponding to each time element and the length of the element time is calculated, all the products are added and summed, and finally the accumulated result is the value corresponding to the peak area measured data, which is used to accurately represent the area size of the background gas chromatographic peak in the corresponding time interval and reflect the measured information related to the content of the background gas in the detection process.

[0057] When the time variable gradually changes in the time interval corresponding to the peak start time value to the peak vertex time value, the absolute value of the difference between the time variable and the value corresponding to the peak vertex time value gradually decreases, both the first function result and the second function result gradually increase, the comprehensive function value gradually increases, the product result corresponding to each time microelement gradually increases after combining with the basic coefficient, and the value corresponding to the peak area measured data presents an upward trend; after the time variable passes the time point corresponding to the peak vertex time value, when the time variable continues to change in the time interval corresponding to the peak vertex time value to the peak end time value, the absolute value of the difference between the time variable and the value corresponding to the peak vertex time value gradually increases, both the first function result and the second function result gradually decrease, the comprehensive function value gradually decreases, the product result corresponding to each time microelement gradually decreases after combining with the basic coefficient, and the value corresponding to the peak area measured data presents a downward trend; when the value corresponding to the preset peak shape mixing factor increases, the weight proportion of the first function result in the comprehensive function value increases, if the peak value of the first function is more concentrated, the value of the comprehensive function value near the peak vertex time value is larger, and the value corresponding to the peak area measured data after integration is correspondingly increased; when the value corresponding to the preset peak shape mixing factor decreases, the weight proportion of the second function result increases, if the peak shape of the second function is more gentle, the distribution of the comprehensive function value in the time interval is more uniform, and the value corresponding to the peak area measured data after integration is correspondingly decreased; when the value corresponding to the peak width of the background gas chromatographic peak at the preset proportion height increases, the change rate of the two functions slows down, the distribution range of the comprehensive function value in the time interval is wider, and the value corresponding to the peak area measured data after integration increases; when the value corresponding to the peak width of the background gas chromatographic peak at the preset proportion height decreases, the change rate of the two functions speeds up, the distribution of the comprehensive function value is more concentrated, and the value corresponding to the peak area measured data after integration decreases; when the value corresponding to the peak height of the background gas chromatographic peak increases, the basic coefficient correspondingly increases, the comprehensive function value as a whole increases in proportion, and the value corresponding to the peak area measured data after integration increases in the same proportion; when the value corresponding to the peak height of the background gas chromatographic peak decreases, the basic coefficient correspondingly decreases, the comprehensive function value as a whole decreases in proportion, and the value corresponding to the peak area measured data after integration decreases in the same proportion.

[0058] The beneficial effect is that the implementation process is screened and verified through multiple steps, first ensures that the peak shape and broadening of the candidate background gas chromatographic peak meet the requirements, then locks the chromatographic peak corresponding to the inherent background gas of the mine through retention time matching, then determines the reliable internal reference channel through the purity singularity, and finally calculates the peak area measured data based on the accurately determined background baseline. The whole process is progressive, effectively eliminates the influence of interference peaks and abnormal signals, provides a stable and accurate internal reference basis for subsequent mine target harmful gas detection, significantly improves the reliability and precision of harmful gas quantitative analysis results, and ensures the accuracy of mine gas monitoring work.

[0059] The working curve construction module 105 is configured to correct the response factor of the target harmful gas in the external reference channel according to the peak area measured data, and evolve the corrected response factor into the real-time quantitative working curve of the mine. In the embodiment of the present application, when the working curve construction module is used to correct the response factor of the target harmful gas in the external reference channel according to the peak area measured data, it is specifically used for: Taking the proportional relationship between the peak area measured data and the standard peak area of the background gas chromatographic peak in the mine as the background interference compensation parameter of the mine; Correlating the background interference compensation parameter and the response factor of the target harmful gas in the external reference channel to obtain the associated response factor of the target harmful gas; According to the distribution characteristics of the background interference compensation parameter, the associated response factor is converged to obtain the corrected response factor of the target harmful gas.

[0060] When the working curve construction module is used to evolve the corrected response factor into the real-time quantitative working curve of the mine, it is specifically used for: Taking the chromatographic peak area of the target harmful gas as the horizontal axis and the gas concentration of the target harmful gas as the vertical axis, a two-dimensional coordinate system of the target harmful gas is constructed; The corrected response factor is mapped into the two-dimensional coordinate system to construct the concentration basic curve of the target harmful gas; According to the signal stability index of the net chromatographic signal in the mine, the slope of the concentration basic curve is adjusted to obtain the optimized concentration curve of the target harmful gas; The environmental parameters of the mine and the real-time state parameters of the portable gas chromatograph are mapped as the boundary constraint conditions of the optimized concentration curve; Under the boundary constraint conditions, the continuity of the optimized concentration curve is verified to obtain the real-time quantitative working curve of the mine.

[0061] The standard peak area of the background gas chromatographic peak in the mine is retrieved, the ratio of the peak area measured data to the standard peak area is calculated, and the ratio is determined as the background interference compensation parameter of the mine.

[0062] The pre-set response factor of the target harmful gas in the external reference channel is retrieved, the background interference compensation parameter and the response factor are multiplied to establish the numerical correlation between the two, and the associated response factor of the target harmful gas is obtained.

[0063] The numerical distribution of the statistical background interference compensation parameter in multiple measurements is determined, the numerical interval of the concentrated distribution is determined, the numerical value of the correlation response factor exceeding the interval is adjusted to the interval, the correlation response factor converges to the concentrated interval, and the corrected response factor of the target harmful gas is obtained.

[0064] A two-dimensional coordinate system of the target harmful gas is established with the chromatographic peak area of the target harmful gas as the horizontal axis and the specific numerical scale marked, and the gas concentration of the target harmful gas as the vertical axis and the corresponding concentration scale marked.

[0065] A plurality of target harmful gas standard samples of different concentrations are selected, the chromatographic peak area and the corresponding concentration of each sample in the two-dimensional coordinate system are measured, the corrected response factor is substituted into the peak area and concentration corresponding relationship of each sample, a plurality of coordinate points are obtained, and the coordinate points are sequentially connected to form a smooth curve to construct a concentration basic curve of the target harmful gas.

[0066] The signal stability index is extracted as the signal amplitude fluctuation amplitude of the net chromatographic signal in the preset time period, if the fluctuation amplitude is large, the signal stability is poor, and the slope of the concentration basic curve is appropriately reduced to reduce the concentration calculation error, if the fluctuation amplitude is small, the signal stability is good, and the slope of the concentration basic curve is kept or slightly adjusted to obtain an optimized concentration curve of the target harmful gas.

[0067] The environmental parameters of the mine are collected, including the environmental temperature, humidity, air pressure, and the real-time state parameters of the portable gas chromatograph, including the carrier gas flow and detector temperature, according to the normal value range of these parameters, the upper limit and lower limit of the peak area and concentration corresponding relationship in the optimized concentration curve are set, and the upper and lower limits are used as boundary constraint conditions of the optimized concentration curve.

[0068] The concentration change between adjacent coordinate points along the horizontal axis direction of the optimized concentration curve is checked point by point, if there is a concentration mutation point, the concentration value of the mutation point is adjusted within the range allowed by the boundary constraint condition to make the curve change smooth, after the continuity verification is completed, a real-time quantitative working curve of the mine is obtained.

[0069] The beneficial effects are that the implementation process corrects the target harmful gas response factor through the background interference compensation parameter, effectively offsets the influence of the background interference on the response factor, and constructs the real-time quantitative working curve in combination with the corresponding relationship between the peak area and the concentration, the signal stability, the environment and instrument parameters, so that the working curve is more suitable for the actual detection scene of the mine, and the accuracy and adaptability of the quantitative analysis of the target harmful gas are improved, and a reliable quantitative basis is provided for the accurate monitoring of the harmful gas in the mine.

[0070] The harmful gas concentration obtaining module 106 is configured to map the peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain the harmful gas concentration information of the mine.

[0071] In the embodiment of the present application, when the harmful gas concentration obtaining module maps the peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain the harmful gas concentration information of the mine, the harmful gas concentration obtaining module is specifically configured to: point-by-point match the peak area of the target harmful gas chromatographic peak with the real-time quantitative working curve to obtain an initial concentration point of the peak area; verify the reliability of the initial concentration point according to the noise level of the net chromatographic signal and the curvature feature of the real-time quantitative working curve to obtain an effective concentration point of the peak area; interpolate and correct the effective concentration point based on the distribution of adjacent points on the real-time quantitative working curve to obtain the harmful gas concentration information of the mine.

[0072] Specifically, the peak area of the target harmful gas chromatographic peak is extracted, the horizontal axis of the real-time quantitative working curve is observed, the horizontal axis corresponds to the peak area of the target harmful gas chromatographic peak, the position point on the horizontal axis that is completely consistent with the extracted peak area value is accurately positioned, a straight line perpendicular to the horizontal axis is drawn along the position point, the straight line intersects with the real-time quantitative working curve to form an intersection point, the concentration value on the vertical axis corresponding to the intersection point is read, and the concentration value is determined as the initial concentration point of the peak area.

[0073] The noise level of the net chromatographic signal is analyzed, the amplitudes of all signal points in the baseline part of the net chromatographic signal are calculated, the maximum value and the minimum value of the amplitudes are found out, the difference between the maximum value and the minimum value is the fluctuation range of the baseline signal, the larger the fluctuation range is, the higher the noise level is, and the smaller the fluctuation range is, the lower the noise level is; meanwhile, the curvature feature of the real-time quantitative working curve is observed, the bending degree of the curve at the position of the horizontal axis corresponding to the initial concentration point is judged, if the change of the tangent slope at the position is small, it indicates that the curvature is gentle, if the change of the tangent slope is large, it indicates that the curvature is large; if the noise level of the net chromatographic signal is low and the curvature at the corresponding position of the working curve is gentle, it is directly determined that the reliability of the initial concentration point is high; if the noise level is high or the curvature is large, the change trend of the initial concentration point and the adjacent concentration points on the working curve is compared, if the initial concentration point obviously deviates from the trend, it is determined that the reliability of the initial concentration point is low and the initial concentration point is removed, and the initial concentration point that meets the trend is reserved as the effective concentration point of the peak area.

[0074] On the real-time quantitative working curve, the two adjacent peak area-concentration points corresponding to the peak area of the effective concentration point on the horizontal axis and the two adjacent peak area-concentration points after the effective concentration point are determined, the four points jointly constitute the adjacent points of the effective concentration point, and the peak area value and the corresponding concentration value of each adjacent point are recorded; the concentration change rule of the adjacent points is analyzed, if the concentration of the adjacent points increases or decreases uniformly and linearly with the increase of the peak area, the average value of the concentration of the four adjacent points is calculated, if the deviation of the effective concentration point from the average value is within the preset allowable range, the effective concentration point is kept unchanged, if the deviation exceeds the range, the concentration of the effective concentration point is adjusted according to the linear change ratio of the adjacent points; if the concentration of the adjacent points changes nonlinearly, the corrected concentration value fitting the change amplitude of the concentration of the adjacent points is calculated, and the corrected concentration value is used to replace the concentration of the original effective concentration point, and the harmful gas concentration information of the mine is obtained through the interpolation correction based on the distribution of the adjacent points.

[0075] The beneficial effect is that the implementation process accurately obtains the initial concentration point through point-by-point matching, verifies the effective concentration point by combining the noise level of the net chromatographic signal and the curvature characteristics of the real-time quantitative working curve, ensures the reliability of the concentration point, and further optimizes the concentration value based on the interpolation correction of the adjacent point distribution, thereby effectively reducing the influence of the peak area matching error, noise interference and local characteristics of the curve on the result, and finally obtaining accurate mine harmful gas concentration information, which provides accurate data support for real-time monitoring, risk warning and safety control of mine harmful gas, and helps to take targeted measures to ensure mine operation safety in time.

[0076] Referring to Figure 2 Fig. 1 is a flowchart of a detection method of a mine harmful gas provided by an embodiment of the present application. In the embodiment, the detection method of the mine harmful gas includes the following steps. S1, collecting a gas sample in a mine by a portable gas chromatograph to obtain original chromatographic data of the mine, and removing baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine; S2, identifying a baseline interval in the standard chromatographic data which does not contain a target harmful gas chromatographic peak, and extracting a signal feature of the baseline interval; S3, inserting the signal feature according to the time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and performing differential analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine; S4, selecting a background gas chromatographic peak in the net chromatographic signal as an internal reference channel of the mine to obtain peak area measured data of the background gas chromatographic peak, and taking a preset standard gas response factor as an external reference channel of the mine; S5. According to the peak area measured data, the response factor of the target harmful gas in the external reference channel is corrected, and the corrected response factor is evolved into a real-time quantitative working curve of the mine; S6. The peak area of the target harmful gas chromatographic peak is mapped to the real-time quantitative working curve to obtain the harmful gas concentration information of the mine.

[0077] It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.

[0078] The embodiments of the present application can acquire and process related data based on artificial intelligence technology. The artificial intelligence is the theory, method, technology and application system for simulating, extending and expanding human intelligence by using a digital computer or a machine controlled by a digital computer, perceiving an environment, acquiring knowledge and using the knowledge to obtain optimal results.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A portable gas chromatograph mine harmful gas detection system, characterized in that, The system comprises a chromatographic data processing module, a signal feature extraction module, a chromatographic signal difference module, a double-channel construction module, a working curve construction module and a harmful gas concentration acquisition module, wherein: The chromatographic data processing module is configured to collect gas samples in a mine by a portable gas chromatograph, obtain original chromatographic data of the mine, and remove baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine. The signal feature extraction module is configured to identify a baseline interval in the standard chromatographic data that does not contain a chromatographic peak of a target harmful gas, and extract a signal feature of the baseline interval. The chromatographic signal difference module is configured to insert the signal feature according to a time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and perform difference analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine. The double-channel construction module is configured to select a background gas chromatographic peak in the net chromatographic signal as an internal reference channel of the mine, acquire peak area measured data of the background gas chromatographic peak, and use a preset standard gas response factor as an external reference channel of the mine. The working curve construction module is configured to correct a response factor of a target harmful gas in the external reference channel according to the peak area measured data, and evolve the corrected response factor into a real-time quantitative working curve of the mine. The harmful gas concentration acquisition module is configured to map a peak area of the chromatographic peak of the target harmful gas to the real-time quantitative working curve to obtain harmful gas concentration information of the mine.

2. The portable gas chromatograph mine harmful gas detection system according to claim 1, characterized in that, When the chromatographic data processing module removes the baseline drift and random noise in the original chromatographic data to obtain the standard chromatographic data of the mine, it is specifically configured to: divide the original chromatographic data into a chromatographic peak signal segment and a baseline noise segment according to signal amplitude and change rate of the original chromatographic data of the mine; suppress high-frequency random fluctuations in the baseline noise segment to obtain a smooth baseline segment of the mine; filter out burr noise of the chromatographic peak signal segment while keeping the basic profile of the chromatographic peak signal segment unchanged to obtain a smooth chromatographic peak segment of the mine; connect the smooth baseline segment and the smooth chromatographic peak segment in time sequence, and correct abnormal discrete points in the spliced signal data to obtain the standard chromatographic data of the mine.

3. The portable gas chromatograph mine harmful gas detection system of claim 1, wherein, When the signal feature extraction module identifies the baseline interval in the standard chromatographic data that does not contain the chromatographic peak of the target harmful gas, and extracts the signal feature of the baseline interval, it is specifically configured to: identify a continuous time segment in the standard chromatographic data whose signal change amplitude continuously drops below a standard threshold value of the standard chromatographic data to obtain an initial candidate interval of the standard chromatographic data; evaluate consistency of signal patterns in the initial candidate interval to obtain a smooth baseline interval of the mine; perform comparison and analysis on time information in the smooth baseline interval and a retention time spectrum of the target harmful gas in the mine to obtain a candidate baseline interval of the mine. Verify the concentration of signal distribution in the candidate baseline interval to obtain the baseline interval of the mine; Perform multi-dimensional analysis on the baseline interval to obtain the signal characteristics of the baseline interval.

4. The portable gas chromatograph mine harmful gas detection system of claim 1, wherein, When the color spectrum signal difference module inserts the signal characteristics according to the time sequence position of the baseline interval to obtain the dynamic baseline signal of the mine, and performs difference analysis on the standard color spectrum data and the dynamic baseline signal to obtain the net color spectrum signal of the mine, specifically for: Taking the center time point of the baseline interval as a time reference, and taking the horizontal reference signal in the signal characteristics as an amplitude reference, a control signal sequence of the mine is established; In the global time range of the standard color spectrum data, the control signal sequence is extended, and reference constraint signals are added at the beginning and end of the global time range to obtain a complete constraint signal set of the standard color spectrum data; The complete constraint signal set is time-aligned with the standard color spectrum data to obtain a dynamic baseline signal of the standard color spectrum data; The dynamic baseline signal is removed from the standard color spectrum data to obtain an initial difference signal of the mine; Low-frequency residues in the initial difference signal are compensated for, and high-frequency burrs in the initial difference signal are smoothed to obtain a net color spectrum signal of the mine.

5. The portable gas chromatograph mine harmful gas detection system of claim 1, wherein, When the double-channel construction module selects a background gas chromatographic peak in the net color spectrum signal as an internal reference channel of the mine to obtain peak area measured data of the background gas chromatographic peak, specifically for: Monitoring the chromatographic peak of the net color spectrum signal, and selecting a chromatographic peak with regular peak shape and stable broadening as a candidate background gas chromatographic peak of the mine from the chromatographic peak; Interval matching is performed on the retention time of the candidate background gas chromatographic peak and the retention time spectrum of the inherent background gas in the mine to obtain a stable background gas chromatographic peak of the mine; The purity of the stable background gas chromatographic peak is analyzed, and a background gas chromatographic peak with single purity is taken as the internal reference channel of the mine; A background baseline of the mine is determined according to the peak start point and the peak end point of the background gas chromatographic peak; The peak area measured data of the background gas chromatographic peak is calculated according to the background baseline.

6. The portable gas chromatograph mine harmful gas detection system of claim 5, wherein, The calculation formula of the peak area measured data is: ； wherein, represents the peak area measured data of the peak, represents the peak height of the background gas chromatographic peak, represents the peak width of the background gas chromatographic peak at a preset proportion height, represents the peak vertex time value of the background gas chromatographic peak, represents the peak start time value of the background gas chromatographic peak, represents the peak end time value of the background gas chromatographic peak, represents a preset peak shape mixing factor, represents an integral function, represents an exponential function, represents a circular constant.

7. The portable gas chromatograph mine gas detection system of claim 1, wherein, When the working curve construction module corrects the response factor of the target harmful gas in the external reference channel according to the peak area measured data, specifically for: Taking the ratio relationship between the peak area measured data and the standard peak area of the background gas chromatographic peak in the mine as a background interference compensation parameter of the mine; Associating the background interference compensation parameter and the response factor of the target harmful gas in the external reference channel to obtain an associated response factor of the target harmful gas; According to the distribution characteristics of the background interference compensation parameter, the associated response factor is converged to obtain a corrected response factor of the target harmful gas.

8. The portable gas chromatograph mine gas detection system of claim 1, wherein, When the working curve construction module evolves the corrected response factor into a real-time quantitative working curve of the mine, specifically for: A two-dimensional coordinate system of the target harmful gas is constructed with a chromatographic peak area of the target harmful gas as an abscissa and a gas concentration of the target harmful gas as an ordinate; The corrected response factor is mapped into the two-dimensional coordinate system to construct a concentration basic curve of the target harmful gas; According to a signal stability index of the net chromatographic signal in the mine, a slope of the concentration basic curve is adjusted to obtain an optimized concentration curve of the target harmful gas; An environmental parameter of the mine and a real-time state parameter of the portable gas chromatograph are mapped as a boundary constraint condition of the optimized concentration curve; Under the boundary constraint condition, continuity of the optimized concentration curve is verified to obtain a real-time quantitative working curve of the mine.

9. The portable gas chromatograph mine gas detection system of claim 1, wherein, When the harmful gas concentration acquisition module maps the peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain harmful gas concentration information of the mine, the harmful gas concentration acquisition module is specifically configured to: The peak area of the target harmful gas chromatographic peak is matched with the real-time quantitative working curve point by point to obtain an initial concentration point of the peak area; According to a noise level of the net chromatographic signal and a curvature feature of the real-time quantitative working curve, the credibility of the initial concentration point is verified to obtain an effective concentration point of the peak area; Based on a distribution of adjacent points on the real-time quantitative working curve, the effective concentration point is interpolated and corrected to obtain the harmful gas concentration information of the mine.

10. A method for detecting harmful gases in a mine using a portable gas chromatograph, characterized by, The method for detecting harmful gas in a mine using the portable gas chromatograph of claim 1 comprises the following steps: S1, collecting a gas sample in the mine by the portable gas chromatograph to obtain original chromatographic data of the mine, and removing baseline drift and random noise in the original chromatographic data to obtain standard chromatographic data of the mine; S2, identifying a baseline interval without a target harmful gas chromatographic peak in the standard chromatographic data, and extracting a signal feature of the baseline interval; S3, inserting the signal feature according to a time sequence position of the baseline interval to obtain a dynamic baseline signal of the mine, and performing differential analysis on the standard chromatographic data and the dynamic baseline signal to obtain a net chromatographic signal of the mine; S4, selecting a background gas chromatographic peak in the net chromatographic signal as an internal reference channel of the mine to obtain peak area measured data of the background gas chromatographic peak, and taking a preset standard gas response factor as an external reference channel of the mine; S5, correcting a response factor of a target harmful gas in the external reference channel according to the peak area measured data, and evolving the corrected response factor into a real-time quantitative working curve of the mine; S6, mapping a peak area of the target harmful gas chromatographic peak to the real-time quantitative working curve to obtain harmful gas concentration information of the mine.

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