Dual mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy

Abstract

The present application relates to the technical field of petroleum engineering logging equipment, and particularly relates to a dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy, which comprises a gas permeation unit for separating hydrocarbon gases, a non-dispersive infrared light source for generating double-light-path independent transmission spectrum output gas spectrum data, an arbitration module for generating an arbitration decision result with a light path mode marker, an analysis module for analyzing pulse signals and identifying spectrum patterns, and an output module for fusing concentration values, light path mode markers and classification codes to generate three-tuple data of deep concentration patterns. The present application dynamically releases characteristics through real-time arbitration matching of double-light-paths, captures transient pulse signals through short light paths, converts formation parameters by identifying peak width symmetry characteristics through the analysis module, and forms an unalterable record chain by correlating time and depth dimensions through the output module, so as to eliminate the misjudgment of formation signals caused by the mismatch between artificial detection cycles and gas release dynamic characteristics.

Description

Technical Field

[0001] This invention relates to the field of oilfield logging equipment technology, and in particular to a dual-mode hydrocarbon source gas detection device and method based on nondispersive infrared spectroscopy. Background Technology

[0002] The dual-mode hydrocarbon source gas detection device using nondispersive infrared spectroscopy employs the principle of infrared radiation transmission. Gas molecules selectively attenuate light intensity in characteristic absorption bands, and the concentration of hydrocarbons such as methane is quantified by analyzing the attenuation signal. In the presence of hydrocarbon source gas, molecular vibrations absorb specific infrared wavelengths, and the detector measures the energy loss of transmitted light to infer the gas content. The dual-mode structure integrates two operating states: high response speed and strong anti-interference capability. The former optimizes real-time dynamic monitoring needs, while the latter suppresses the influence of coexisting components through path switching. For example, it balances detection speed and accuracy in complex industrial emissions, thereby improving system adaptability and reliability, and widely serving the safety maintenance of oil and gas pipelines and the control of chemical processes.

[0003] The fundamental flaw of existing gas logging technology in gas detection lies in the conflict between intermittent manual operation and the dynamic characteristics of formation gas release. For example, in limestone formation exploration, the hydrocarbon gas released from porous reservoirs presents as brief high-concentration pulses. However, existing equipment requires on-site personnel to manually replace the adsorption tube to enrich the gas and restart the calibration program, which takes more than 8 minutes. By the time the detection is restored, the peak value of the key gas has decayed to the background level, causing weak karst pores to be misjudged as invalid layers in the logging curve, ultimately resulting in the oil testing operation accidentally drilling through the main producing layer. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a dual-mode hydrocarbon source gas detection device and method based on non-dispersive infrared spectroscopy, which solves the problem of missed detection of key formation signals due to the mismatch between the dynamic release of hydrocarbon gases and the detection cycle of manual intervention.

[0005] To solve the above-mentioned technical problems, the specific details of the present invention are as follows:

[0006] In a first aspect, the present invention provides a dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy, comprising:

[0007] The data acquisition module is used to collect dynamically released hydrocarbon gases through the gas permeation unit and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including the transmittance matrix.

[0008] The arbitration module is used to arbitrate the gas spectral data, dynamically select short or long optical path output mode according to the confidence index, and generate an arbitration decision result including optical path mode marking.

[0009] The analysis module is used to receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and the formation permeability classification code;

[0010] The output module is used to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data.

[0011] The gas spectral data output by the data acquisition module is transmitted to the arbitration module and the analysis module. The arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module. The pulse signal analysis result output by the analysis module is transmitted to the output module. The output module pushes triplet data to capture transient gas release characteristics, solving the problem of missed detection caused by the mismatch between the manual intervention detection cycle and the dynamic release signal.

[0012] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the gas permeation unit includes a fluoropolymer semi-permeable membrane, which isolates liquid and rock debris while allowing hydrocarbon gas molecules to permeate into the detection chamber.

[0013] The permeated hydrocarbon gas molecules are transported to the detection chamber, where they are irradiated by a non-dispersive infrared light source to generate gas spectral data.

[0014] Furthermore, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in this invention, the beam splitter of the dual optical path receives the non-dispersive infrared light source and splits the incident light into a short optical path channel beam and a long optical path channel beam.

[0015] The short optical path channel beam illuminates the first detector through a direct path, generating first spectral data;

[0016] The long optical path channel beam illuminates the second detector after being folded through the reflector group, generating second spectral data;

[0017] The first and second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

[0018] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the arbitration module calculates the short optical path signal-to-noise ratio as a partial confidence index, and the short optical path signal-to-noise ratio quantifies the signal reliability of characteristic absorption peaks in gas spectral data.

[0019] At the same time, the long optical path interference suppression rate is calculated as another confidence index. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectral data.

[0020] The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode based on the confidence index and outputs the arbitration decision result.

[0021] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the arbitration rule execution submodule receives the confidence index and selects the short optical path output mode based on whether the rate of change of the characteristic absorption peak in the confidence index exceeds a set threshold.

[0022] When the environmental interference parameter exceeds the standard, the long optical path output mode is forcibly selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard.

[0023] The submodule outputs the arbitration decision result to the parsing module and the output module, and the decision result generates an optical path selection mark.

[0024] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the analysis module receives the optical path mode marker in the arbitration decision result, and when the marker indicates the short optical path output mode, the long optical path calculation task is interrupted.

[0025] The pulse signal processing submodule of the analysis module receives short-path spectral data from the gas spectral data and extracts the abrupt change features of the absorption peak;

[0026] The pulse signal processing submodule generates a concentration-time curve;

[0027] The concentration-time curve input analysis module's spectral morphology recognition submodule identifies spectral features and outputs them to the pulse signal analysis results.

[0028] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the spectral morphology recognition submodule extracts the peak width and symmetry features of the concentration-time curve;

[0029] The preset morphology template library is called to match the features, and a morphology consistency index is generated.

[0030] The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis results.

[0031] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the output module receives a system clock signal and superimposes a timestamp onto the concentration value in the pulse signal analysis result;

[0032] Read the optical path mode marker from the arbitration decision result and encode it as a status value;

[0033] The drilling depth data input in real time from the logging system is correlated with the formation permeability classification code;

[0034] The concentration value, state value, and classification code after integrating the superimposed timestamps are used to generate triplet data;

[0035] The triplet data is pushed to the logging system via a communication interface.

[0036] Furthermore, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the communication interface receives triplet data and an error retransmission mechanism, and uses an industrial protocol to encapsulate and generate data frames.

[0037] A verification code is added to the communication interface during the encapsulation process;

[0038] Push the data frame with added verification code to the logging system;

[0039] The error retransmission mechanism monitors the response signal returned by the logging system;

[0040] When the response signal indicates that the verification failed, the most recently stored valid frame data will be retransmitted.

[0041] The valid frame data is extracted from the local cache of the communication interface.

[0042] Secondly, the dual-mode hydrocarbon source gas detection method based on nondispersive infrared spectroscopy provided by the present invention, applied to the aforementioned dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy, includes:

[0043] Step 1: Collect dynamically released hydrocarbon gases through a gas permeation unit, and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including a transmittance matrix.

[0044] Step 2: Arbitrate the gas spectral data, dynamically select short or long optical path output mode based on confidence index, and generate arbitration decision results including optical path mode markings;

[0045] Step 3: Receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and formation permeability classification code;

[0046] Step 4: Integrate the concentration value from the pulse signal analysis result, the optical path mode marker from the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data.

[0047] The gas spectral data output in step 1 is transmitted to steps 2 and 3. The arbitration decision result output in step 2 is transmitted to steps 3 and 4. The pulse signal analysis result output in step 3 is transmitted to step 4. Step 4 pushes triplet data to capture transient gas release characteristics.

[0048] Beneficial effects of this invention;

[0049] The beneficial effects of this invention lie in the dual-optical-path arbitration mechanism dynamically adapting to gas release characteristics. A short optical path with high temporal resolution captures millisecond-level concentration pulse signals. The arbitration module switches detection modes in real time based on the rate of change of characteristic absorption peaks, eliminating the time mismatch between fixed sampling periods and transient release events. The resource scheduling algorithm of the analysis module interrupts non-critical computational tasks, focusing on processing abrupt changes in spectral absorption peaks, generating millisecond-level concentration-time curves, and extracting peak width symmetry parameters, converting them into formation permeability classification codes to avoid missing weak anomalies during manual interpretation. The output module superimposes high-precision timestamps and associates them with drilling depth coordinates, fusing optical path state values ​​to form depth-concentration morphology triplet data. This data is then encapsulated using an industrial protocol and transmitted via a communication link with a retransmission mechanism. The gas release characteristic data, cross-validated in both spatiotemporal dimensions, is solidified in real time into the logging system, preventing the risk of losing critical geological signals due to lag in manual recording and subjective misjudgment. Attached Figure Description

[0050] To more clearly illustrate the present invention, the accompanying drawings used in the embodiments will be briefly described below. Obviously, those skilled in the art can obtain other drawings based on the accompanying drawings without any creative effort.

[0051] Figure 1 This is a system architecture diagram of a dual-mode hydrocarbon source gas detection method based on nondispersive infrared spectroscopy provided in an embodiment of the present invention. Detailed Implementation

[0052] To make the objectives, advantages, and features of this invention clearer, the invention will be described clearly and completely below with reference to specific embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The invention provided by various embodiments will be described in detail below with reference to the accompanying drawings. To better understand the objectives of this invention, it will be described in further detail below.

[0053] In a first aspect, the present invention provides a dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy, comprising:

[0054] The data acquisition module is used to collect dynamically released hydrocarbon gases through the gas permeation unit and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including the transmittance matrix.

[0055] The arbitration module is used to arbitrate the gas spectral data, dynamically select short or long optical path output mode according to the confidence index, and generate an arbitration decision result including optical path mode marking.

[0056] The analysis module is used to receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and the formation permeability classification code;

[0057] The output module is used to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data.

[0058] The gas spectral data output by the data acquisition module is transmitted to the arbitration module and the analysis module. The arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module. The pulse signal analysis result output by the analysis module is transmitted to the output module. The output module pushes triplet data to capture transient gas release characteristics, solving the problem of missed detection caused by the mismatch between the manual intervention detection cycle and the dynamic release signal.

[0059] The gas permeation unit of the data acquisition module is equipped with a fluoropolymer semi-permeable membrane. This membrane selectively isolates liquid components and solid rock cuttings in the drilling fluid based on the principle of molecular sieves, while allowing small hydrocarbon gas molecules to diffuse and permeate. After the hydrocarbon gas molecules enter the sealed detection chamber, a broadband infrared beam is generated by a non-dispersive infrared light source. This beam is split into two independently transmitted short-path and long-path optical paths by a beam splitter. The short-path optical path adopts a direct-light optical path design so that the beam directly illuminates the detector, while the long-path optical path is folded multiple times through a set of reflectors to form a folded optical path. The transmission spectrum data acquired by the two channels are then combined to generate gas spectrum data in the form of a transmittance matrix.

[0060] After receiving the gas spectral data, the arbitration module calculates the signal-to-noise ratio (SNR) of the characteristic absorption peak in the short-path channel and the interference suppression rate in the long-path channel. The short-path SNR quantifies the reliability of the spectral signal in the methane characteristic band, while the long-path interference suppression rate assesses the anti-interference capability in the water vapor interference band. These two confidence indices are input into the arbitration rule engine. When the rate of change of the characteristic absorption peak exceeds a dynamic threshold, the short-path output mode is activated; when the concentration of environmental interference components exceeds the limit, the long-path mode is forcibly switched. Finally, the arbitration decision result carrying an optical path selection flag is output.

[0061] The analysis module synchronously receives gas spectral data and arbitration decision results. When the optical path mode marker indicates short optical path mode, the long optical path data processing thread is interrupted and computational resources are allocated to the short optical path channel. The pulse signal processing unit extracts the absorption peak abrupt change characteristics of the short optical path spectrum and generates a dynamic curve of concentration change over time. This curve is input to the spectral morphology recognition unit, which analyzes the peak width geometry and symmetry parameters to match a preset formation permeability type template. The generated morphology consistency index is written into the formation permeability classification code field, and the pulse signal analysis result containing the concentration value and classification code is output.

[0062] The output module is associated with the system timing unit and the depth sensor of the logging system. The system clock signal is a concentration value superimposed with a time stamp, the optical path mode mark is encoded and converted into a status identifier, and the drilling depth data is associated with the formation permeability classification code to form a depth morphology mapping. The three sets of data are fused to generate a triplet dataset, which is then encapsulated through the industrial bus protocol and a cyclic redundancy check (CRC) code is added. When the encapsulated data frame is pushed to the logging system via the communication interface, the error retransmission mechanism monitors the link layer response signal. If the check fails, the most recent valid frame in the local cache is called for retransmission.

[0063] Each module forms a closed-loop data processing link: the gas permeation physical layer acquires the raw signal, the arbitration layer dynamically optimizes the detection path, the analysis layer identifies transient release characteristics, and the output layer fuses spatiotemporal dimension information. The data stream is continuously transmitted from the spectral acquisition end to the communication output end, and the spectral feature dimension and engineering parameter dimension are cross-validated to eliminate the time-domain mismatch problem between the manual interpretation period and the dynamic release event.

[0064] Specifically, the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy of the present invention includes a gas permeation unit comprising a fluoropolymer semipermeable membrane, which isolates liquid and rock debris while allowing hydrocarbon gas molecules to permeate into the detection chamber.

[0065] The permeated hydrocarbon gas molecules are transported to the detection chamber, where they are irradiated by a non-dispersive infrared light source to generate gas spectral data.

[0066] The fluoropolymer semi-permeable membrane is made of polytetrafluoroethylene or perfluoroalkoxy resin, and its microporous structure achieves selective permeation based on the diameter of gas molecules. This semi-permeable membrane is positioned between the drilling fluid flow path and the detection chamber. The micropore diameter on the membrane surface is designed to range from 0.3 to 0.5 nanometers, which can block liquid water molecules and rock cuttings larger than 1 micrometer. Hydrocarbon gas molecules, with molecular diameters of 0.38 nanometers for methane and 0.44 nanometers for ethane, penetrate the membrane structure through molecular diffusion, forming a gaseous enrichment zone within the detection chamber.

[0067] The permeation process follows Fick's diffusion law, with hydrocarbon gas molecules continuously migrating into the detection chamber driven by a concentration gradient. The detection chamber maintains a constant negative pressure environment, controlled by a micro-vacuum pump to keep the internal pressure 0.1 to 0.3 atmospheres lower than the external drilling fluid pressure. This pressure difference accelerates the rate at which gas molecules penetrate the semi-permeable membrane while preventing reverse permeation of the drilling fluid. Once the gas concentration in the enriched zone increases, a non-dispersive infrared light source emits a broadband infrared beam that penetrates vertically into the detection chamber.

[0068] The non-dispersive infrared light source employs a silicon carbide ceramic-based blackbody radiator, operating at a temperature maintained between 600 and 800 Kelvin. The radiated beam enters the detection cavity through a calcium fluoride optical window, penetrating a gas-rich region with an optical path length of 15 to 30 millimeters. Hydrocarbon gas molecules absorb infrared energy of specific wavelengths, causing an attenuation in the transmitted light intensity; this attenuation characteristic follows the Beer-Lambert law relationship with the gas concentration. This process generates the original spectral signal, which is then input to the photoelectric conversion unit.

[0069] The output port of the detection cavity is connected to a dual-path beam splitter system, which splits the attenuated infrared beam into independent transmission paths. The dual-channel optical signals are transmitted separately to the short-path and long-path detectors in a spatially separated state, avoiding measurement errors caused by optical path crosstalk. The two detectors simultaneously acquire transmission spectrum data, providing a dual-mode detection basis for the subsequent arbitration module.

[0070] The gas permeation unit and the optical detection unit form a series working chain: the semi-permeable membrane completes the separation and extraction of substances, the detection chamber standardizes the gaseous medium, and the optical system captures molecular absorption characteristics. This design eliminates the shading effect of mud foam on optical measurements, while avoiding the risk of damage to optical devices caused by rock debris scraping, maintaining the continuity and stability of the spectral data acquisition process.

[0071] Specifically, in the dual-mode hydrocarbon source gas detection device based on non-dispersive infrared spectroscopy described in this invention, the beam splitter of the dual optical path receives the non-dispersive infrared light source and splits the incident light into a short optical path channel beam and a long optical path channel beam.

[0072] The short optical path channel beam illuminates the first detector through a direct path, generating first spectral data;

[0073] The long optical path channel beam illuminates the second detector after being folded through the reflector group, generating second spectral data;

[0074] The first and second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

[0075] The beam splitter employs a cubic prism optical beam-splitting component, with its incident surface coated with a broadband anti-reflection film to reduce reflection loss. The diverging beam emitted from a non-dispersive infrared source is converted into parallel light by a collimating lens and incident on the dichroic coating interface of the beam splitter. This coating layer achieves semi-transmissive and semi-reflective characteristics in the 3-5 micrometer wavelength range, separating the incident beam into a short-path transmission beam and a long-path reflection beam, with the two beams propagating in 90-degree orthogonal directions.

[0076] The short optical path channel transmits the beam along a straight path, with the beam divergence angle controlled within 0.2 degrees. An achromatic focusing lens group is configured in the direct optical path to converge the parallel beam onto the photosensitive target surface of the first detector. The first detector employs a lead sulfide photoconductive sensor with a response time of less than 10 milliseconds. After the beam penetrates the gas sample within a 5 mm effective optical path, the light intensity attenuation signal is converted into a first spectral data electrical signal by a transimpedance amplifier.

[0077] The long-path beam, after being reflected by a beam splitter, enters an optical path folding system consisting of four sets of off-axis parabolic mirrors. The first mirror deflects the beam by 90 degrees, and the subsequent three sets of mirrors extend the optical path length to 50 times the reference distance using a non-coplanar folding method. The beam output from the end mirror is focused by a spherical field mirror and illuminates the mercury cadmium telluride photovoltaic sensitive area of ​​the second detector. During the folding process, the beam transmission distance is controlled to 150 mm, generating second spectral data with high-resolution characteristics.

[0078] The dual-channel data synchronous acquisition unit includes a clock phase-locked circuit, and the output signals of the first and second detectors are aligned with their timestamps via a synchronous sample-and-hold circuit. The two electrical signals are input to a differential analog-to-digital converter, and after common-mode noise is eliminated, they are merged into a composite spectral dataset. This dataset contains a dual-channel transmittance matrix, and its data dimensions correspond to the absorption characteristic spectral lines of gas molecules.

[0079] The beam-splitting structure forms a dual-mode collaborative measurement system: the short optical path channel maintains high temporal resolution, rapidly capturing transient gas pulse changes; the long optical path channel provides high-sensitivity detection capability, accurately quantifying low-concentration gas components. The physical isolation of the dual-channel data avoids spectral aliasing errors in traditional time-division measurements, providing a differentiated feature analysis basis for the arbitration module.

[0080] Specifically, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the arbitration module calculates the short optical path signal-to-noise ratio as a partial confidence index, and the short optical path signal-to-noise ratio quantifies the signal reliability of characteristic absorption peaks in gas spectral data.

[0081] At the same time, the long optical path interference suppression rate is calculated as another confidence index. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectral data.

[0082] The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode based on the confidence index and outputs the arbitration decision result.

[0083] After receiving the dual-channel gas spectral data, the arbitration module uses the short-path data processing unit to calculate the signal-to-noise ratio (SNR) parameter of the characteristic absorption peaks. This parameter is obtained by comparing the amplitude variation of the absorption valley in the methane characteristic band with the baseline noise level, where the baseline noise originates from the detector's dark current and light source fluctuations. The SNR quantization coefficient reflects the current short-path channel's ability to track transient gas concentration changes; a higher SNR value indicates stronger signal reliability.

[0084] The long optical path data processing unit synchronously calculates the interference suppression rate index, focusing on analyzing the background noise attenuation characteristics of the water vapor interference band. The anti-interference capability assessment employs a band-stop filtering algorithm to eliminate non-target gas absorption lines while preserving the integrity of hydrocarbon characteristic peaks. The interference suppression rate coefficient is directly related to the stability of the measurement system in a water-bearing drilling fluid environment; a higher value indicates better environmental adaptability.

[0085] The confidence index analysis engine processes dual-path parameters using a sliding time window. A high-response mode is triggered when the short-path signal-to-noise ratio fluctuation exceeds a dynamically preset threshold; an environmental interference alarm is triggered when the long-path interference suppression rate falls below a critical value. The two-path index input rule base matcher performs weighted decision-making, based on historical operating data analysis and formation fluid characteristic models.

[0086] The arbitration rule execution submodule generates arbitration decision results that include an optical path mode flag. When the short optical path signal-to-noise ratio (SNR) remains within the optimal range, the mode flag is set to a high response state; when the interference suppression rate falls below the safety threshold, the flag is forcibly switched to anti-interference mode. The output decision result carries a timestamp and channel selection parameters, providing optical path control commands to downstream modules.

[0087] A dual-mode arbitration mechanism forms the core of adaptive detection: the signal-to-noise ratio ensures real-time pulse signal acquisition, while interference suppression maintains measurement accuracy in complex environments. The system can dynamically switch optical path characteristics based on formation gas release features, resolving the mismatch between fixed detection modes and dynamic release processes. Decision results are synchronously transmitted to the analysis and output modules via a data bus.

[0088] Specifically, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the arbitration rule execution submodule receives the confidence index and selects the short optical path output mode based on whether the change rate of the characteristic absorption peak in the confidence index exceeds a set threshold.

[0089] When the environmental interference parameter exceeds the standard, the long optical path output mode is forcibly selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard.

[0090] The submodule outputs the arbitration decision result to the parsing module and the output module, and the decision result generates an optical path selection mark.

[0091] After receiving the confidence index input, the arbitration rule execution submodule uses the characteristic absorption peak change rate analysis unit to calculate the instantaneous slope of the methane characteristic band in real time. This slope value is obtained by calculating the first derivative of the spectral data using a differential algorithm, reflecting the rate of change of gas concentration. When the differential value exceeds the dynamic adjustment threshold for three consecutive sampling periods, the logic processor determines that the short optical path mode activation condition is met. The decision state machine sets a high-response flag, indicating that the short optical path data channel should be used preferentially.

[0092] The environmental interference monitoring unit monitors the long optical path interference suppression rate in parallel, focusing on tracking the suppression level of water vapor interference components in characteristic bands. When the absorption intensity of water vapor in the 3.0-micron band exceeds the preset safety boundary, the anti-interference coefficient falls below the critical level. The state converter triggers a forced switching command, overriding the current optical path mode setting and locking the optical path selection parameters to the long optical path anti-interference mode.

[0093] The decision generation engine integrates dual-path decision signals and outputs structured arbitration decision results. The result data structure includes three parts: timestamp, optical path mode marker, and confidence parameter snapshot. The optical path mode marker uses a binary encoding format to represent the channel selection status with minimal data volume. The timestamp is synchronized with the acquisition clock of the data acquisition module to maintain the timing consistency of the entire system.

[0094] The decision results are synchronously transmitted to downstream modules via a parallel data bus. Data packets transmitted to the parsing module include raw spectral index pointers, maintaining the association between spectral data and decision parameters. The decision results transmitted to the output module extract optical path selection markers, which are converted into status identifiers during the data integration phase. A data frame verification mechanism is employed during transmission to prevent transmission errors from causing inaccurate control commands.

[0095] A dynamic decision-making mechanism forms the core of dual-mode collaborative control: monitoring changes in characteristic absorption peaks ensures timely pulse signal acquisition, while environmental interference threshold determination maintains measurement reliability. An arbitration mechanism based on real-time operating conditions optimizes detection resource allocation, establishing a balance between transient response and anti-interference capability. The output of the optical path mode marker provides a unified control benchmark for downstream processing, supporting the system's adaptive operation under complex geological conditions.

[0096] Specifically, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the analysis module receives the optical path mode mark in the arbitration decision result, and when the mark indicates the short optical path output mode, the long optical path calculation task is interrupted.

[0097] The pulse signal processing submodule of the analysis module receives short-path spectral data from the gas spectral data and extracts the abrupt change features of the absorption peak;

[0098] The pulse signal processing submodule generates a concentration-time curve;

[0099] The concentration-time curve input analysis module's spectral morphology recognition submodule identifies spectral features and outputs them to the pulse signal analysis results.

[0100] When the optical path mode flag is read as short optical path output mode by the parsing module, the computing resource scheduler immediately suspends the long optical path data processing task. The scheduler releases digital signal processor resources through the interrupt controller, reallocating floating-point units and memory bandwidth to the short optical path data processing flow. Simultaneously, it freezes write operations to the long optical path data buffer to prevent invalid data from occupying the system bus, thus dynamically tilting computing resources towards critical channels.

[0101] The pulse signal processing submodule receives the redirected short-path spectral data stream, and the feature extraction unit uses a sliding differential algorithm to track the absorption peak change trajectory. A second-order derivative transform is performed on the spectral curve of methane's characteristic band, and abrupt absorption peak events are located by zero-crossing detection. Each abrupt change point is associated with a timestamp and absorption depth parameters, forming a discrete feature point sequence that is output to the concentration reconstruction unit.

[0102] The concentration reconstruction unit converts the feature point sequence into concentration parameters based on the Beer-Lambert absorption law. The time-dimensional alignment module compensates for optical path transmission delay and circuit response lag, generating a concentration data stream with millisecond-level time accuracy. This data stream is then smoothed using a Kalman filter, outputting a dynamic curve of concentration changing over time, with the data point intervals meeting the requirements for analyzing instantaneous release events.

[0103] The spectral morphology recognition submodule receives the concentration-time curve, and the feature geometry analyzer calculates the full width at half maximum (FWHM) and symmetry index of the absorption peak. The FWHM parameter obtains the chromatographic peak broadening characteristics through Gaussian fitting, and the symmetry index is quantified using the left-right half-peak area ratio method. These two parameters are input into a template matching engine, which compares their similarity with pre-stored high-permeability fractured, medium-permeability porous, and low-permeability tight formation templates.

[0104] The morphological feature recognition results are written into the pulse signal analysis result data structure. This structure includes three parts: a concentration data array, a formation permeability classification code, and a feature confidence score. The formation permeability classification code uses a three-bit encoding scheme to characterize the matching template type and its morphological consistency level. The final result is transmitted to the output module via a parallel bus to complete the dynamic feature analysis of the pulse release event.

[0105] Specifically, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the spectral morphology recognition submodule extracts the peak width and symmetry features of the concentration-time curve.

[0106] The preset morphology template library is called to match the features, and a morphology consistency index is generated.

[0107] The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis results.

[0108] The peak width feature extraction unit receives the concentration-time curve and uses the half-peak full-width algorithm to calculate the width of the gas absorption peak. This algorithm locates the position from the peak to the maximum concentration, and determines the width boundary points at concentrations decreasing by 50% on both sides of the peak. The peak width value characterizes the diffusion rate of the gas release process. Simultaneously, the symmetry calculation module analyzes the geometric characteristics of the peak profile, quantifying the peak symmetry index by the ratio of the distance from the left boundary to the peak to the distance from the right boundary to the peak, reflecting the homogeneity of the formation's permeability structure.

[0109] The feature parameter set is input into the template matching engine, which calls a pre-stored formation permeability morphology template library for similarity comparison. The template library contains three types of standard spectra: high-permeability fracture type, medium-permeability porosity type, and low-permeability tight type. Each type of template stores the peak width benchmark value and symmetry benchmark range of typical concentration-time curves. The similarity calculation uses the Euclidean distance algorithm to map the measured peak width and symmetry into a multi-dimensional feature space and measure the degree of deviation from the standard template.

[0110] The matching result generation module outputs a morphological consistency index, which expresses the degree of agreement between the measured features and the target template as a percentage. The index calculation is a weighted result that combines peak width matching degree and symmetry deviation degree, with the weighting coefficients preset based on geological exploration experience data. When the measured parameters simultaneously fall within the peak width tolerance zone and symmetry tolerance zone of the target template, the index is automatically increased to the preferred range.

[0111] The data writing controller loads the morphological consistency index into the structured dataset of the pulse signal analysis results and locks it into the formation permeability classification code field. The classification code uses a three-bit binary encoding format, with the high-order bits identifying the template type and the low-order bits carrying the index classification information. The writing operation is synchronized with the timestamp of the original concentration data to maintain the spatiotemporal consistency of the data records.

[0112] Template-driven analysis establishes a mapping relationship between spectral morphology and geological properties: peak width characteristics reflect formation fluid transport capacity, and symmetry indicates the degree of heterogeneity of reservoir pore structure. The consistency index, as a quantitative evaluation indicator, is embedded in the classification code structure, providing programmable and analytical permeability parameters for the logging system, supporting rapid identification of reservoir properties during drilling.

[0113] Specifically, in the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention, the output module receives a system clock signal and superimposes a timestamp onto the concentration value in the pulse signal analysis result.

[0114] Read the optical path mode marker from the arbitration decision result and encode it as a status value;

[0115] The drilling depth data input in real time from the logging system is correlated with the formation permeability classification code;

[0116] The concentration value, state value, and classification code after integrating the superimposed timestamps are used to generate triplet data;

[0117] The triplet data is pushed to the logging system via a communication interface.

[0118] The system clock signal is input to the output module through a precision timing circuit, and this signal source is synchronized with the Coordinated Universal Time (UTC) system. The timestamp overlay processor reads the concentration value data stream from the pulse signal analysis results and uses a hardware-level time stamping unit to add a microsecond-level time stamp to each concentration sampling point. The stamping process follows the IEEE 1588 precision time protocol, and the time stamp is embedded in the extended field of the concentration data frame to form an enhanced data packet with complete time-domain characteristics.

[0119] The optical path mode tag decoder extracts the binary encoded signal from the arbitration decision result. The tag conversion logic circuit performs state mapping according to a predefined encoding table: short optical path mode is encoded as a high-response state identifier, and long optical path mode is encoded as an anti-interference state identifier. The conversion process maintains the integrity of the encoded metadata, and the output state value maintains a strict correspondence with the original tag.

[0120] The drilling depth correlation unit interfaces with the logging system data bus to acquire drilling depth pulse signals generated by the rotary encoder in real time. The depth data calibration module eliminates drill pipe compression errors and measurement hysteresis effects, generating absolute coordinate values ​​for the current well depth. These coordinate values ​​are indexed and associated with the formation permeability classification code in a relational database, and the depth data is bound to formation characteristic parameters through a foreign key constraint mechanism.

[0121] The data fusion engine performs the integration of three information streams. The concentration data packets with time-domain labels are loaded into the triplet concentration data field, the optical path state identifier is written into the state value field, and the formation permeability classification code from the depth index is loaded into the morphological data field. The fusion process follows a packet serialization protocol to generate structured triplet data blocks, with the block header containing a frame synchronization sequence and a length checksum.

[0122] The communication interface controller receives triplet data blocks and encapsulates the application layer data using the industrial real-time Ethernet protocol. During encapsulation, a transmission control header and data link layer address are added, and the data is pushed to the remote terminal of the logging system via a physical layer signal driver. The push mechanism employs both periodic and event-triggered modes, prioritizing the transmission of abnormal status data while maintaining the basic transmission rate.

[0123] A multi-dimensional data fusion mechanism constructs a feature association system: time stamping enables the temporal location of transient gas events, depth association establishes a vertical distribution map of formation characteristics, and status indicators provide feedback on the system's operating conditions. The ternary data structure provides the analytical basis for spatiotemporal correlation of the logging system, supporting the dynamic geological interpretation of gas release events during drilling.

[0124] Specifically, the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy described in this invention has a communication interface that receives triplet data and an error retransmission mechanism, and uses an industrial protocol to encapsulate and generate data frames.

[0125] A verification code is added to the communication interface during the encapsulation process;

[0126] Push the data frame with added verification code to the logging system;

[0127] The error retransmission mechanism monitors the response signal returned by the logging system;

[0128] When the response signal indicates that the verification failed, the most recently stored valid frame data will be retransmitted.

[0129] The valid frame data is extracted from the local cache of the communication interface.

[0130] The data encapsulation unit of the communication interface receives the triplet data stream generated by the output module, using the real-time industrial Ethernet protocol as the application layer transmission standard. The encapsulation process constructs a seven-layer protocol stack structure: the destination MAC address and source device identifier are added at the data link layer; the IP datagram header is allocated at the network layer; and the TCP retransmission control mechanism is implemented at the transport layer. The application layer payload contains triplet data blocks, and the entire data frame structure conforms to the ISO / IEC standardization framework.

[0131] The frame check sequence generator performs cyclic redundancy check (CRC) calculations at the end of the encapsulation. This calculation generates a 32-bit checksum based on the CRC-32 polynomial, which is appended to the frame check sequence field at the end of the data frame. The checksum covers the area from the start-of-frame character to the application-layer data tail, providing the ability to detect bit errors during transmission. The data frame with the added checksum is temporarily stored in the transmit buffer queue.

[0132] The data frame push engine retrieves complete frames from the buffer queue and converts them into Manchester-coded electrical signals via a physical layer differential signal driver. The signals are then transmitted to the logging system receiver via twisted-pair or fiber optic media. The push timing controller employs a dual-mode approach: fixed-period polling and interrupt triggering. While maintaining the basic transmission rate, it prioritizes the transmission of flagged data frames with abnormal states.

[0133] The error retransmission mechanism's acknowledgment monitoring unit continuously monitors link layer control signals. The standard acknowledgment protocol generated by the logging system receiver includes frame sequence number acknowledgment and checksum status bits. The status parser compares the sent frame sequence number with the acknowledgment number in the acknowledgment frame. When the checksum status bit is set to fail or no acknowledgment is received three times consecutively, a data retransmission request signal is triggered.

[0134] After responding to a retransmission request, the retransmission executor retrieves the most recently valid frame data from the local circular buffer of the communication interface. This buffer stores original copies of sent data frames and maintains a fixed capacity using a first-in, first-out replacement strategy. Retransmitted frames are added with a special retransmission flag and inserted at the head of the transmission queue, taking precedence over regular data frames. If a failure response is still received after retransmission, the process is escalated to an exception handling procedure, and the link quality assessment report is updated.

[0135] A data integrity maintenance mechanism establishes a reliable transmission assurance system: standardized protocol encapsulation maintains compatibility with heterogeneous systems, cyclic redundancy check provides bit-level error detection, and acknowledgment monitoring and retransmission control respond to link quality fluctuations. A local caching mechanism provides temporary storage for critical data, preventing geological information loss due to transient failures and supporting the logging system in continuously acquiring highly reliable formation gas release characteristics.

[0136] Secondly, please refer to Figure 1 The present invention provides a dual-mode hydrocarbon source gas detection method based on nondispersive infrared spectroscopy, which is applied to the aforementioned dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy, comprising:

[0137] Step 1: Collect dynamically released hydrocarbon gases through a gas permeation unit, and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including a transmittance matrix.

[0138] Step 2: Arbitrate the gas spectral data, dynamically select short or long optical path output mode based on confidence index, and generate arbitration decision results including optical path mode markings;

[0139] Step 3: Receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and formation permeability classification code;

[0140] Step 4: Integrate the concentration value from the pulse signal analysis result, the optical path mode marker from the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data.

[0141] The gas spectral data output in step 1 is transmitted to steps 2 and 3. The arbitration decision result output in step 2 is transmitted to steps 3 and 4. The pulse signal analysis result output in step 3 is transmitted to step 4. Step 4 pushes triplet data to capture transient gas release characteristics.

[0142] This invention utilizes a dual-optical-path system to generate independent short-path and long-path channels via a beam splitter, maintaining high temporal resolution in the short-path path. An arbitration module calculates both the rate of change of the characteristic absorption peak in the short-path path and the interference suppression rate in the long-path path in real time, activating the short-path mode immediately when the change in the characteristic absorption peak exceeds a dynamic threshold. The optical path mode flag triggers the parsing module to interrupt the long-path calculation task, concentrating computing power to process the millisecond-level pulse signals in the short-path spectrum, thus avoiding the omission of transient signals caused by manually setting a fixed sampling period.

[0143] The pulse signal processing submodule of the analysis module extracts the abrupt change trajectory of short-path spectral absorption peaks, generating millisecond-level concentration-time curves. The spectral morphology recognition submodule analyzes the peak width and symmetry characteristics of the curves, matches them with preset templates for high-permeability fractured, medium-permeability porous, and low-permeability tight formations, generates a morphology consistency index, and writes it into the formation permeability classification code. This process transforms the transient characteristics of gas release into quantifiable formation parameters, avoiding the neglect of weak anomalous signals during manual interpretation.

[0144] The output module overlays concentration values ​​with microsecond-level timestamps, while simultaneously linking them to the real-time drilling depth and formation permeability classification codes from the logging system. The fused depth-concentration-morphology triplet data is encapsulated using an industrial protocol and pushed to the logging system via an error retransmission mechanism. The time dimension marks and locks the pulse occurrence moment, the depth dimension correlates and locates the released stratigraphic level, and the morphology classification code translates into geological meaning. These three dimensions of data collaboratively construct an irreversible recording chain, preventing the loss of critical information due to delays and misjudgments in manual recording.

Claims

1. A dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy, characterized in that, include: The data acquisition module is used to collect dynamically released hydrocarbon gases through the gas permeation unit and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including the transmittance matrix. The arbitration module is used to arbitrate the gas spectral data, dynamically select short or long optical path output mode according to the confidence index, and generate an arbitration decision result including optical path mode marking. The analysis module is used to receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and the formation permeability classification code; The output module is used to fuse the concentration value in the pulse signal analysis result, the optical path mode mark in the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data. The gas spectral data output by the data acquisition module is transmitted to the arbitration module and the analysis module. The arbitration decision result output by the arbitration module is transmitted to the analysis module and the output module. The pulse signal analysis result output by the analysis module is transmitted to the output module. The output module pushes triplet data to capture transient gas release characteristics. The arbitration module calculates the short optical path signal-to-noise ratio as a partial confidence index, and the short optical path signal-to-noise ratio quantifies the signal reliability of characteristic absorption peaks in gas spectral data. At the same time, the long optical path interference suppression rate is calculated as another confidence index. The long optical path interference suppression rate evaluates the anti-interference ability of the interference band in the gas spectral data. The confidence index is input into the arbitration rule execution submodule, which selects the optical path mode based on the confidence index and outputs the arbitration decision result. The arbitration rule execution submodule receives the confidence index and selects the short optical path output mode based on whether the change rate of the characteristic absorption peak in the confidence index exceeds a set threshold. When the environmental interference parameter exceeds the standard, the long optical path output mode is forcibly selected, and the component corresponding to the long optical path interference suppression rate of the environmental interference parameter exceeds the standard. The submodule outputs the arbitration decision result to the parsing module and the output module, and the decision result generates an optical path selection mark; The parsing module receives the optical path mode flag from the arbitration decision result. When the flag indicates a short optical path output mode, the long optical path calculation task is interrupted. The pulse signal processing submodule of the analysis module receives short-path spectral data from the gas spectral data and extracts the abrupt change features of the absorption peak; The pulse signal processing submodule generates a concentration-time curve; The concentration-time curve input analysis module's spectral morphology recognition submodule identifies spectral features and outputs them to the pulse signal analysis results. The spectral morphology recognition submodule extracts the peak width and symmetry features of the concentration-time curve; The preset morphology template library is called to match the features, and a morphology consistency index is generated. The morphological consistency index is written into the formation permeability classification code field in the pulse signal analysis results.

2. The dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy according to claim 1, characterized in that, The gas permeation unit includes a fluoropolymer semi-permeable membrane, which isolates liquids and rock fragments while allowing hydrocarbon gas molecules to permeate into the detection chamber. The permeated hydrocarbon gas molecules are transported to the detection chamber, where they are irradiated by a non-dispersive infrared light source to generate gas spectral data.

3. The dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy according to claim 2, characterized in that, The dual-path beam splitter receives a non-dispersive infrared light source and splits the incident light into a short-path channel beam and a long-path channel beam. The short optical path channel beam illuminates the first detector through a direct path, generating first spectral data; The long optical path channel beam illuminates the second detector after being folded through the reflector group, generating second spectral data; The first and second spectral data are combined to form the gas spectral data, which is then transmitted to the arbitration module.

4. The dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy according to claim 3, characterized in that, The output module receives the system clock signal and adds a timestamp to the concentration value in the pulse signal parsing result; Read the optical path mode marker from the arbitration decision result and encode it as a status value; The drilling depth data input in real time from the logging system is correlated with the formation permeability classification code; The concentration value, state value, and classification code after integrating the superimposed timestamps are used to generate triplet data; The triplet data is pushed to the logging system via a communication interface.

5. The dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy according to claim 4, characterized in that, The communication interface receives triplet data and has an error retransmission mechanism, and uses an industrial protocol to encapsulate and generate data frames. A verification code is added to the communication interface during the encapsulation process; Push the data frame with added verification code to the logging system; The error retransmission mechanism monitors the response signal returned by the logging system; When the response signal indicates that the verification failed, the most recently stored valid frame data will be retransmitted. The valid frame data is extracted from the local cache of the communication interface.

6. A dual-mode hydrocarbon source gas detection method based on nondispersive infrared spectroscopy, applied to the dual-mode hydrocarbon source gas detection device based on nondispersive infrared spectroscopy as described in any one of claims 1 to 5, characterized in that, include: Step 1: Collect dynamically released hydrocarbon gases through a gas permeation unit, and generate dual-path independent transmission spectra using a non-dispersive infrared light source, outputting gas spectral data including a transmittance matrix. Step 2: Arbitrate the gas spectral data, dynamically select short or long optical path output mode based on confidence index, and generate arbitration decision results including optical path mode markings; Step 3: Receive the gas spectral data and the arbitration decision result, analyze the pulse signal and identify the spectral morphology features, and output the pulse signal analysis result containing the concentration value and formation permeability classification code; Step 4: Integrate the concentration value from the pulse signal analysis result, the optical path mode marker from the arbitration decision result, and the formation permeability classification code, and output triplet data to the logging system. The triplet data includes depth data, concentration data, and morphology data. The gas spectral data output in step 1 is transmitted to steps 2 and 3. The arbitration decision result output in step 2 is transmitted to steps 3 and 4. The pulse signal analysis result output in step 3 is transmitted to step 4. Step 4 pushes triplet data to capture transient gas release characteristics.

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