Gas logging system and method in deep-sea conduit-free drilling and production environment

Abstract

The invention relates to the technical field of offshore oil and gas exploration, in particular to a gas logging system and method in a deep-sea conduit-free drilling and production environment, and the system comprises a gas collection module, a gas analysis module, a correction module, a control module and a decision support module. The gas collection module captures gas components in drilling fluid and converts the gas components into bioelectric waveform signals to be output. And the gas analysis module receives the bioelectric waveform signal and converts the bioelectric waveform signal into a digital concentration value for output. And the correction module generates corrected gas concentration and risk probability value output. And the control module responds to the risk probability value grading triggering early warning signal and the control command, and outputs a detection configuration instruction to the gas analysis module. And the decision support module outputs a drilling parameter optimization instruction. Gas transmission delay caused by conduit slurry circulation dependence is eliminated, the problem that conventional equipment loses efficacy in the deep-sea high-pressure low-temperature corrosion environment is solved, and real-time gas detection, well control risk early warning and accurate response of an automatic control system to underground abnormity are achieved.

Description

Technical Field

[0001] This invention relates to the field of marine oil and gas exploration technology, and in particular to a gas logging system and method for deep-sea pipeless drilling and production environments. Background Technology

[0002] In deep-sea drilling and production environments without conduits, gas logging technology continuously monitors the content of hydrocarbon components such as methane and ethane, as well as non-hydrocarbon gases, in the gas returned from drilling fluid to identify potential oil and gas layers and assess formation fluid characteristics. Due to the lack of conduit barriers, formation fluids can easily and rapidly invade the wellbore, increasing well control risks. Therefore, gas logging is crucial for real-time early warning of gas intrusion and overflow. The high pressure and low temperature conditions in the deep sea may affect gas solubility and desorption dynamics. It is necessary to integrate mud gas separation efficiency assessment and pressure gradient correction to improve the accuracy of gas response, thereby providing a reliable basis for drilling optimization and risk assessment.

[0003] Current gas logging technologies heavily rely on mud circulation systems and guide pipe structures, leading to delays in gas detection. This is because gas must circulate with the mud to surface analysis equipment before it can be detected, a process that is time-consuming. In deep-sea drilling and production environments without guide pipes, the lack of a complete mud circulation path further exacerbates these delays. Additionally, the high pressure and low temperature corrosion conditions in the deep sea can easily cause conventional equipment to fail. For example, drilling disturbances in natural gas hydrate exploration can trigger rapid hydrate decomposition and instantaneous gas release. Existing delayed detection methods cannot capture these changes in time, resulting in unannounced gas intrusion events and increased blowout risk, hindering the real-time control system from achieving precise risk adjustment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a gas logging system and method for deep-sea tubular drilling and production environments. This invention solves the technical problems caused by the reliance on tubular mud circulation paths in existing gas logging technologies, which leads to gas transmission delays, and the inability of conventional equipment to withstand the high-pressure, low-temperature, and corrosive environment of deep seas, resulting in real-time gas detection failure, delayed well control risk warnings, and the inability of automatic control systems to accurately respond to downhole anomalies.

[0005] To solve the above-mentioned technical problems, the specific details of the present invention are as follows: In a first aspect, the gas logging system for deep-sea pipeless drilling and production environments provided by the present invention includes: The gas acquisition module is deployed at the drilling wellhead to capture gas components in the drilling fluid underwater in situ and convert the captured gas into a bioelectric waveform signal output. The gas analysis module receives the bioelectric waveform signal output by the gas acquisition module and converts the bioelectric waveform signal into a digital concentration value for output. The calibration module receives the digital concentration value output by the gas analysis module and the real-time bottom hole physical signal input from the outside, and fuses the digital concentration value and the real-time bottom hole physical signal to generate a calibrated gas concentration and risk probability value output. The control module receives the risk probability value output by the correction module, responds to the received risk probability value to trigger a graded early warning signal and generate a control command output, and outputs a detection configuration instruction to the gas analysis module. The decision support module receives the corrected gas concentration and risk probability value of multiple well sections output by the correction module, as well as the equipment status information output by the correction module, and outputs drilling parameter optimization instructions after integration. The gas acquisition module receives the control command output by the control module to adjust the sampling behavior; The calibration module receives the detection configuration command output by the control module and adjusts the calibration behavior.

[0006] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the gas acquisition module includes a dynamic membrane adjustment function, which receives wellbore pressure fluctuation data input, adjusts the electric field strength according to the wellbore pressure fluctuation data to change the membrane pore size, thereby improving the efficiency of gas capture; and uses the changed membrane pore size to capture gas components and output the bioelectric waveform signal.

[0007] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the gas analysis module includes a redundant sensor array, receives the digital concentration value input, identifies when the hydrogen sulfide concentration in the digital concentration value exceeds a preset threshold, generates a switching command to shut down non-critical detection channels, and outputs a channel status flag reflecting the current detection channel status.

[0008] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the correction module receives externally input drill string vibration spectrum signals, digital concentration values ​​output by the gas analysis module, and externally input real-time bottom hole physical signals; based on the drill string vibration spectrum signals, the digital concentration values, and the real-time bottom hole physical signals, a seepage state probability matrix is ​​constructed to output the risk probability value, and a corresponding correction factor is selected based on the seepage state probability matrix.

[0009] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the control module receives the risk probability value output by the correction module; performs a graded judgment on the risk probability value; when the risk probability value is determined to exceed a first threshold, it outputs a high-frequency sampling command to the gas acquisition module; and when the risk probability value is determined to exceed a second threshold, it outputs a lockout command to the blowout preventer system.

[0010] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the decision support module receives the equipment status code output by the correction module; parses the equipment status code; and, based on the parsing result, generates spare parts placement coordinates and drilling speed adjustment suggestions.

[0011] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the control module sends a channel shielding command to the gas analysis module; after receiving the channel shielding command, the gas analysis module closes at least one non-critical detection channel to reduce detection time and outputs the digital concentration value.

[0012] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environment described in this invention, the correction module outputs equipment fault markers to the decision support module; the decision support module generates equipment maintenance coordinates based on the equipment fault markers.

[0013] Furthermore, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the gas acquisition module receives a high-frequency trigger command output by the control module; in response to the high-frequency trigger command, it switches to a millisecond-level continuous sampling mode, captures gas components, and outputs the bioelectric waveform signal; the decision support module receives the risk probability values ​​of multiple continuous well sections output by the correction module; identifies that the risk probability values ​​of the multiple continuous well sections show an increasing trend; and outputs a mud density adjustment value in response to the identification result.

[0014] Secondly, the gas logging method for deep-sea pipeless drilling and production environments provided by this invention is applied to the gas logging system in the deep-sea pipeless drilling and production environment as described above, including: Step 1: Deployed at the drilling wellhead location for underwater in-situ capture of gas components in drilling fluid and conversion of the captured gas into bioelectric waveform signal output; Step 2: Receive the bioelectric waveform signal output in Step 1, and convert the bioelectric waveform signal into a digital concentration value for output. Step 3: Receive the digital concentration value output from Step 2 and the real-time bottom hole physical signal input from the outside, and fuse the digital concentration value and the real-time bottom hole physical signal to generate a corrected gas concentration and risk probability value output. Step 4: Receive the risk probability value output in Step 3, respond to the received risk probability value to trigger a graded early warning signal and generate a control command output, and Step 4 outputs a detection configuration instruction to Step 2; Step 5: Receive the corrected gas concentration and risk probability value of multiple well sections output in Step 3, as well as the equipment status information output in Step 3, and output drilling parameter optimization instructions after integration. Step 1 receives the control command output in step 4 to adjust the sampling behavior; Step 3 receives the detection configuration command output in step 4 to adjust and correct the behavior.

[0015] Beneficial effects of this invention; This invention's technical solution eliminates the path dependence of existing guide tube mud circulation by using the underwater in-situ capture and neural coding output mechanism of the gas acquisition module, achieving millisecond-level gas signal acquisition and solving the transmission delay problem. The redundant sensor array and self-compensation structure of the gas analysis module, combined with the multi-physics field fusion correction algorithm of the correction module, overcomes the influence of the high-pressure, low-temperature, and corrosive environment of the deep sea, ensuring data stability and equipment continuity under extreme conditions. The hierarchical response mechanism of the control module links the dynamic reconstruction of the front-end module, driving the blowout preventer system to execute well control actions in seconds, solving the defects of early warning lag and automatic control failure. The resource prediction and optimization strategy of the decision support module forms a closed-loop maintenance link, actively avoiding drilling risks, and comprehensively improving the real-time performance, reliability, and control accuracy of gas logging in the deep-sea guide tubeless drilling and production environment. Attached Figure Description

[0016] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0017] Figure 1 A flowchart of a gas logging method in a deep-sea pipeless drilling and production environment provided in an embodiment of the present invention. Detailed Implementation

[0018] To make the technical solution of the present invention clearer, the present invention will be clearly and completely described below with reference to specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. The present invention provided by various embodiments will be described in detail below with reference to the accompanying drawings. To better understand the purpose of the present invention, the present invention will be described in further detail below.

[0019] In a first aspect, the gas logging system for deep-sea pipeless drilling and production environments provided by the present invention includes: The gas acquisition module is deployed at the drilling wellhead to capture gas components in the drilling fluid underwater in situ and convert the captured gas into a bioelectric waveform signal output. The gas analysis module receives the bioelectric waveform signal output by the gas acquisition module and converts the bioelectric waveform signal into a digital concentration value for output. The calibration module receives the digital concentration value output by the gas analysis module and the real-time bottom hole physical signal input from the outside, and fuses the digital concentration value and the real-time bottom hole physical signal to generate a calibrated gas concentration and risk probability value output. The control module receives the risk probability value output by the correction module, responds to the received risk probability value to trigger a graded early warning signal and generate a control command output, and outputs a detection configuration instruction to the gas analysis module. The decision support module receives the corrected gas concentration and risk probability value of multiple well sections output by the correction module, as well as the equipment status information output by the correction module, and outputs drilling parameter optimization instructions after integration. The gas acquisition module receives the control command output by the control module to adjust the sampling behavior; The calibration module receives the detection configuration command output by the control module and adjusts the calibration behavior.

[0020] This invention provides a gas logging system for deep-sea tubular drilling environments, comprising multiple functional modules that work collaboratively to address issues such as gas detection delays, poor equipment environmental tolerance, and real-time control failures in existing technologies. The following supplementary technical solutions and explanations of each step of the technical solution are provided to ensure that those skilled in the art clearly understand the logical relationships and data flow between modules. The description uses standardized technical terminology; for example, "gas acquisition module" always refers to the underwater in-situ gas capture function, "bioelectric waveform signal" refers to the concentration encoding output, and "risk probability value" refers to the gas intrusion risk assessment result. The data flow logic between modules is as follows: the gas acquisition module acquires raw data, the gas analysis module processes it into quantifiable values, the correction module integrates environmental signals for optimization, the control module responds to risks in real time, and the decision support module makes comprehensive decisions and provides feedback, forming a closed-loop system to achieve efficient early warning and drilling optimization. The supplementary technical solutions are based on the characteristics of the deep-sea high-pressure and low-temperature environment, avoiding reliance on tubular mud circulation paths.

[0021] The gas acquisition module is deployed at the wellhead, directly contacting the drilling fluid through underwater in-situ capture technology. It uses a dynamically adjustable membrane structure to adsorb gas components and converts the captured gas into a bioelectric waveform signal output. Specific underlying technologies include a polyorganosiloxane smart membrane unit, which automatically adjusts the membrane pore size in response to wellbore pressure fluctuations. Under high pressure, the pore size shrinks to inhibit seawater permeation, while under low pressure, it expands to improve light hydrocarbon capture efficiency. Neuronal pulse frequency modulation technology encodes the gas concentration sequence into voltage spike waveforms, achieving millisecond-level data acquisition and eliminating transmission delays caused by existing mud circulation dependencies. The module receives control commands to adjust its sampling behavior; for example, high-frequency trigger commands activate continuous sampling mode, improving response speed. This step, through in-situ capture and neural coding technology, solves the problem of gas acquisition delay in deep-sea, ductless environments, providing rapid input for subsequent analysis.

[0022] The gas analysis module receives the bioelectric waveform signal output from the gas acquisition module and converts it into a digital concentration value output through a signal restoration unit. The lower-level technology employs a redundant sensor array design, including a non-dispersive infrared main channel for detecting methane and carbon dioxide, and an electrochemical backup channel dedicated to hydrogen sulfide. When the hydrogen sulfide concentration in the digital concentration value exceeds a preset threshold, a switching command is generated to shut down non-critical detection channels, outputting a marker reflecting the current channel status, reducing detection time and improving efficiency. The module receives detection configuration commands, such as channel masking commands, to force resource concentration and enhance the sensitivity of remaining sensors. This step, combined with an anti-interference architecture and adaptive switching logic, overcomes the failure risk of conventional equipment due to high pressure and low temperature corrosion in the deep sea, achieving data stability and providing accurate concentration input for the calibration module.

[0023] The calibration module receives digital concentration values ​​from the gas analysis module and real-time bottom-hole physical signals from external input, including temperature, pressure, and drill string vibration spectra. It fuses these signals to generate calibrated gas concentration and risk probability values. The lower-level technology uses a hidden Markov model to construct a seepage state probability matrix. This matrix calculates the formation fluid seepage state transition probability based on the vibration energy mutation rate and pressure gradient, outputting a risk probability value. Simultaneously, it selects calibration factors based on the seepage state; for example, Henry's law is applied to correct solubility in steady-state conditions, and a turbulent diffusion model is used to compensate for mixing effects in critical states, generating equipment status codes to indicate sensor health. The module receives detection configuration commands and adjusts calibration behavior, such as algorithm locking to handle high-risk events. This step, through multi-physics data fusion and dynamic calibration mechanisms, eliminates environmental interference biases, improves gas response accuracy, and provides a reliable risk assessment for the control module.

[0024] The control module receives the risk probability value output by the correction module, responds to this value by triggering graded early warning signals and generating control commands, and outputs detection configuration instructions to the gas analysis module. Lower-level technology performs graded judgments on the risk probability value, setting different thresholds to drive responses. For example, when the risk probability value exceeds the first threshold, a high-frequency sampling command is output to the gas acquisition module to accelerate data acquisition; when it exceeds the second threshold, a lockout command is output to the blowout preventer system to trigger emergency well control, and a channel shielding command is sent to the gas analysis module to optimize resource allocation. The control commands generated by the module are directly fed back to the front-end module, achieving millisecond-level feedback. This step, through graded early warning and reverse control chains, achieves real-time capture of gas intrusion events and precise automatic system response, avoiding the risk of blowouts.

[0025] The decision support module receives corrected gas concentrations, risk probability values, and equipment status information for multiple well sections from the correction module, integrates them, and outputs drilling parameter optimization commands. Lower-level technologies include a closed-loop strategy generation unit, which analyzes the increasing risk trend of consecutive well sections, generates mud density adjustment values ​​or drilling rate adjustment suggestions, outputs spare parts placement coordinates based on equipment status codes, triggers underwater robot maintenance, clears fault markers, and restores system health. After integrating the data, the module outputs optimization commands to the drilling rig control system to execute parameter adjustments. This step achieves closed-loop optimization of drilling operations through dynamic resource allocation and visual reports, proactively avoiding risks and supporting the efficient operation of the overall system.

[0026] The logical relationships between the modules form a closed-loop data flow. The in-situ capture of the gas acquisition module eliminates delays, the redundant design of the gas analysis module resists environmental failures, the multi-signal fusion of the calibration module improves accuracy, the hierarchical response of the control module drives real-time actions, and the comprehensive optimization feedback of the decision support module is fed back to the front end to collaboratively solve technical problems. This structure achieves real-time performance and reliability of gas logging in deep-sea pipeless drilling and production environments.

[0027] Specifically, the gas logging system for deep-sea pipeless drilling and production environments described in this invention includes a gas acquisition module with a dynamic membrane adjustment function. This module receives wellbore pressure fluctuation data input, adjusts the electric field strength according to the wellbore pressure fluctuation data to change the membrane pore size, thereby improving the efficiency of gas capture. It then uses the changed membrane pore size to capture gas components and outputs the bioelectric waveform signal.

[0028] The dynamic membrane regulation function of the gas acquisition module receives wellbore pressure fluctuation data input, which originates from real-time monitoring values ​​of downhole pressure sensors. Based on the pressure fluctuation data, it automatically adjusts the electric field strength applied to the polyorganosiloxane membrane. When the electric field increases, the membrane pore size shrinks to the micrometer level to inhibit seawater permeation; when the electric field decreases, the membrane pore size expands, improving the capture efficiency of light hydrocarbon gases. The membrane structure, with its changed pore size, captures light hydrocarbon components such as methane in the drilling fluid. Using neuronal pulse frequency modulation technology, the gas concentration changes are encoded as voltage spike waveform signals, and a bioelectric waveform signal is output to the gas analysis module. This mechanism achieves adaptive optimization of in-situ gas capture efficiency according to the pressure environment, avoiding the path dependence of existing conduit transport methods.

[0029] Specifically, the gas logging system for deep-sea pipeless drilling and production environments described in this invention includes a gas analysis module comprising a redundant sensor array. The module receives the digital concentration value input, identifies when the hydrogen sulfide concentration in the digital concentration value exceeds a preset threshold, generates a switching command to close non-critical detection channels, and outputs a channel status flag reflecting the current detection channel status.

[0030] The redundant sensor array of the gas analysis module receives its own output digital concentration value, which includes the hydrogen sulfide concentration parameter. When the hydrogen sulfide concentration exceeds a preset safety threshold, a solid-state relay is triggered to cut off the carbon dioxide detection circuit of the non-dispersive infrared sensor, keeping only the electrochemical sensor channel operational. Simultaneously, a marker signal indicating the currently active channel status is output. This marker signal is binary-coded, recording the channel's off state and a timestamp, and is transmitted to the calibration module for equipment status analysis. By shutting down non-critical detection channels, signal interference is reduced, improving the hydrogen sulfide detection response speed.

[0031] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the correction module receives externally input drill string vibration spectrum signals, digital concentration values ​​output by the gas analysis module, and externally input real-time bottom hole physical signals; based on the drill string vibration spectrum signals, the digital concentration values, and the real-time bottom hole physical signals, a seepage state probability matrix is ​​constructed to output the risk probability value, and a corresponding correction factor is selected based on the seepage state probability matrix.

[0032] The correction module receives drill string vibration spectrum signals from external sensors, digital concentration values ​​from the gas analysis module, and bottom hole temperature and pressure signals. Based on the characteristic frequency energy distribution of the drill string vibration spectrum, the gas concentration variation trend, and bottom hole physical parameters, a hidden Markov probability matrix characterizing the formation seepage state is constructed. This matrix outputs a risk probability value to quantify the gas intrusion risk level. Based on the current state type of the seepage state probability matrix, a solubility correction factor or a turbulence diffusion correction factor is automatically selected and applied to the gas concentration compensation calculation, outputting the corrected gas concentration after environmental interference compensation.

[0033] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the control module receives the risk probability value output by the correction module; performs a graded judgment on the risk probability value; when the risk probability value is determined to exceed a first threshold, it outputs a high-frequency sampling command to the gas acquisition module; and when the risk probability value is determined to exceed a second threshold, it outputs a lockout command to the blowout preventer system.

[0034] The control module receives the risk probability value output by the correction module and performs gradient grading on this value. When the risk probability value exceeds the first warning threshold, it outputs a pulse-width modulated high-frequency sampling command to the gas acquisition module; when the risk probability value exceeds the second safety threshold, it outputs a Manchester-coded lockout command to the blowout preventer control system. The high-frequency sampling command triggers the gas acquisition module to enter millisecond-level sampling mode, and the lockout command drives the blowout preventer hydraulic valve to close the wellhead passage, forming a two-stage well control response mechanism.

[0035] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the decision support module receives the equipment status code output by the correction module; parses the equipment status code; and generates spare parts placement coordinates and drilling speed adjustment suggestions based on the parsing results.

[0036] The decision support module receives the equipment status code output by the correction module. This code is a multi-bit fault code. It parses the bit combinations of the equipment status code to identify the specific fault type and location coordinates, generating a 3D coordinate command for spare parts placement and a recommended drilling rate adjustment value. The coordinate command is transmitted to the underwater robot navigation system, and the drilling rate adjustment value is output to the drilling rig control unit, enabling precise location maintenance of faulty equipment and optimization of drilling efficiency.

[0037] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the control module sends a channel shielding command to the gas analysis module; after receiving the channel shielding command, the gas analysis module closes at least one non-critical detection channel to reduce detection time and outputs the digital concentration value.

[0038] The control module sends a channel shielding command to the gas analysis module, which is triggered by a low-level signal. Upon receiving the channel shielding command, the gas analysis module immediately shuts down preset non-critical gas detection channels to reduce the computational latency caused by multi-channel parallel processing, keeping only the core detection channels running and outputting digital concentration values. Dynamic resource allocation shortens the single detection cycle, meeting real-time requirements under high-risk conditions.

[0039] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the correction module outputs equipment fault markers to the decision support module; the decision support module generates equipment maintenance coordinates based on the equipment fault markers.

[0040] When a correction factor fails consecutively, the correction module generates a fault marker and outputs it to the decision support module. This marker includes the sensor identifier and the cumulative deviation value. Based on the location identifier in the fault marker, the decision support module uses the equipment topology map to generate underwater maintenance coordinates. The maintenance coordinates are three-dimensional data of latitude, longitude, and depth, which are output to the spare parts scheduling system to initiate the replacement process and eliminate correction errors caused by equipment malfunctions.

[0041] Specifically, in the gas logging system for deep-sea pipeless drilling and production environments described in this invention, the gas acquisition module receives a high-frequency trigger command output by the control module; in response to the high-frequency trigger command, it switches to a millisecond-level continuous sampling mode, captures gas components, and outputs the bioelectric waveform signal; the decision support module receives the risk probability values ​​of multiple consecutive well sections output by the correction module; identifies that the risk probability values ​​of the multiple consecutive well sections show an increasing trend; and outputs a mud density adjustment value in response to the identification result.

[0042] The gas acquisition module receives a high-frequency trigger command from the control module, which is a square wave pulse sequence. Responding to the rising edge of the high-frequency trigger command, it switches to a millisecond-level continuous sampling mode, increasing the gas component capture frequency and outputting a high-density bioelectric waveform signal. The decision support module receives risk probability values ​​for three consecutive well sections from the correction module. After identifying a monotonically increasing trend in the probability values, it calls the drilling parameter optimization algorithm to calculate the mud density adjustment value and outputs a density increment command to the mud pump control system to balance the wellbore pressure.

[0043] Secondly, please refer to Figure 1 The gas logging method for deep-sea pipeless drilling and production environments provided by this invention is applied to the gas logging system in the deep-sea pipeless drilling and production environment as described above, and includes: Step 1: Deployed at the drilling wellhead location for underwater in-situ capture of gas components in drilling fluid and conversion of the captured gas into bioelectric waveform signal output; Step 2: Receive the bioelectric waveform signal output in Step 1, and convert the bioelectric waveform signal into a digital concentration value for output. Step 3: Receive the digital concentration value output from Step 2 and the real-time bottom hole physical signal input from the outside, and fuse the digital concentration value and the real-time bottom hole physical signal to generate a corrected gas concentration and risk probability value output. Step 4: Receive the risk probability value output in Step 3, respond to the received risk probability value to trigger a graded early warning signal and generate a control command output, and Step 4 outputs a detection configuration instruction to Step 2; Step 5: Receive the corrected gas concentration and risk probability value of multiple well sections output in Step 3, as well as the equipment status information output in Step 3, and output drilling parameter optimization instructions after integration. Step 1 receives the control command output in step 4 to adjust the sampling behavior; Step 3 receives the detection configuration command output in step 4 to adjust and correct the behavior.

[0044] This invention addresses the shortcomings of existing technologies through a modular collaborative mechanism and a closed-loop feedback architecture. The gas acquisition module is directly deployed at the wellhead, utilizing dynamic membrane regulation to capture gas components in the drilling fluid in situ. Neuron pulse coding technology is then used to convert the gas concentration into a real-time bioelectric waveform signal. This design eliminates the physical path of gas relying on mud circulation for sea surface detection, compressing the existing minute-level transmission delay to the millisecond level, and overcoming the bottleneck of gas transmission delay caused by conduit dependence.

[0045] The gas analysis module employs a titanium-zirconium alloy sealed cavity and a redundant sensor array, with non-dispersive infrared sensors and electrochemical sensors operating in parallel. When hydrogen sulfide concentration exceeds the limit, non-critical detection channels are automatically shut down. A self-compensating pressure-reducing unit maintains a constant pressure environment, and a built-in molecular sieve eliminates interference from the high humidity of deep-sea environments. This multi-modal redundancy architecture maintains detection continuity under high pressure, low temperature, and corrosive conditions, avoiding real-time detection interruptions caused by conventional equipment failure.

[0046] The correction module integrates multi-physics field signals to establish a dynamic compensation mechanism. It receives digital concentration values ​​from the gas analysis module and simultaneously integrates drill string vibration spectrum, bottom hole temperature and pressure signals to construct a flow state probability matrix and output risk probability values. Based on the flow state, it automatically switches between Henry's Law solubility correction and turbulence diffusion correction factors to eliminate the dynamic influence of high-pressure, low-temperature environments on gas analysis and improve the accuracy of concentration data.

[0047] The control module implements graded response and reverse control reconfiguration. Based on risk probability values, graded trigger commands are implemented: when the first threshold is exceeded, a high-frequency sampling command is output to the gas acquisition module, activating a millisecond-level continuous sampling mode; when the second threshold is exceeded, a lockout command is output to the blowout preventer system. Simultaneously, a channel shielding command is sent to the gas analysis module, and an algorithm switching command is sent to the calibration module, forcing the front-end modules to reconfigure their operating logic. This multi-module concurrent response mechanism shortens the cycle from downhole anomaly identification to well control action execution to the second level.

[0048] The decision support module forms a resource prediction and optimization chain. It analyzes and corrects the equipment status codes output by the module to generate spare parts deployment coordinates, and coordinates with the underwater robot to replace faulty components in advance. It also identifies the increasing risk trend in continuous well sections, outputs mud density adjustment values, and drives the drilling rig control system to adjust operating parameters. This predictive mechanism transforms reactive measures into proactive avoidance, and collaborates with front-end modules to build self-maintenance capabilities.

[0049] The technical solution addresses the core issues through a four-fold synergistic effect: in-situ data acquisition eliminates transmission delays, multimodal redundancy mitigates environmental failures, closed-loop feedback achieves second-level response, and predictive optimization proactively mitigates risks. The data flows from each module form a complete closed loop: the gas acquisition module outputs a signal to the gas analysis module, the calibration module integrates environmental parameters to optimize the data, the control module hierarchically drives the actuators, and the decision support module provides feedback on resource scheduling instructions.

[0050] The gas logging system for deep-sea tubular drilling and production environments is deployed at the wellhead, directly facing the challenges of high pressure and low-temperature corrosion. The gas acquisition module uses a polyorganosiloxane intelligent membrane unit as its core component. This unit responds to wellbore pressure fluctuations by automatically adjusting the electric field strength to change the membrane pore size; under high pressure, it shrinks the pore size to the micrometer level to suppress seawater permeation, while under low pressure, it expands the pore size to improve the capture efficiency of light hydrocarbon gases. It utilizes the dynamic changes in membrane pore size to capture gas components in the drilling fluid and encodes the gas concentration sequence into a voltage spike waveform signal output through neuronal pulse frequency modulation technology, achieving millisecond-level in-situ data acquisition. This mechanism eliminates the path dependence of existing tubular mud circulation, solving the gas transmission delay problem. When the gas acquisition module receives a high-frequency trigger command from the control module, it switches to a millisecond-level continuous sampling mode, further optimizing the response speed.

[0051] The gas analysis module receives the bioelectric waveform signal output from the gas acquisition module and converts it into a digital concentration value output through a signal restoration unit. The module includes a redundant sensor array design; the main channel uses a non-dispersive infrared sensor to detect methane and carbon dioxide, while the backup channel uses an electrochemical sensor specifically for hydrogen sulfide. When the hydrogen sulfide concentration in the digital concentration value exceeds a preset safety threshold, a solid-state relay is triggered to shut down non-critical detection channels, keeping only the core channel running and outputting a binary-coded channel status flag. This array design, combined with a titanium-zirconium alloy sealed cavity and a molecular sieve dehumidification unit, resists the high-pressure, low-temperature corrosion environment of the deep sea, ensuring data stability. The gas analysis module responds to channel shielding commands sent by the control module, forcibly shutting down non-critical detection channels to reduce detection time and improve real-time analysis efficiency under high-risk conditions.

[0052] The calibration module receives digital concentration values ​​from the gas analysis module and real-time bottom-hole physical signals from external input, including temperature, pressure, and drill string vibration spectrum signals. The module constructs a seepage state probability matrix using a hidden Markov model. This matrix calculates the formation fluid seepage state transition probability based on the vibration energy mutation rate and pressure gradient, outputting a risk probability value to quantify the gas intrusion risk level. Simultaneously, based on the current state type of the seepage state probability matrix, it automatically selects either a solubility correction factor or a turbulence diffusion correction factor for gas concentration compensation. For example, Henry's Law is applied to correct solubility deviations in steady-state conditions, while a turbulence diffusion model is used to compensate for mixing effects in critical states, generating a corrected gas concentration. The calibration module outputs a device status code to indicate sensor health and adjusts calibration behavior in response to detection configuration commands from the control module, such as algorithm locking to handle high-risk events. This multi-physics fusion mechanism eliminates detection deviations caused by environmental interference, improving early warning accuracy.

[0053] The control module receives the risk probability value output by the correction module and performs tiered judgment processing. When the risk probability value exceeds the first warning threshold, it outputs a pulse-width modulated high-frequency sampling command to the gas acquisition module, activating a millisecond-level continuous sampling mode. When the risk probability value exceeds the second safety threshold, it outputs a Manchester-coded lockout command to the blowout preventer system, driving the hydraulic valve to close the wellhead channel. Simultaneously, the control module outputs detection configuration commands to the gas analysis module, such as channel shielding commands to optimize resource allocation, and sends an algorithm switching command to the correction module to force a reconfiguration of the working logic. This tiered response mechanism achieves second-level capture of gas intrusion events and real-time execution of well control actions, resolving the defects of early warning lag and automatic control failure.

[0054] The decision support module receives corrected gas concentrations, risk probability values, and equipment status information for multiple well sections from the correction module. The module parses the multi-bit fault codes of the equipment status codes, identifies the specific fault type and location coordinates, and generates a 3D coordinate command for spare parts deployment, which is transmitted to the underwater robot navigation system. Simultaneously, it analyzes the increasing trend of risk probability values ​​in consecutive well sections and calls the drilling parameter optimization algorithm to output mud density adjustment values ​​or drilling speed adjustment suggestions to the drilling rig control unit. This closed-loop strategy generation unit proactively avoids drilling risks and supports resource prediction and optimization. After integrating the data, the decision support module outputs drilling parameter optimization commands, forming a closed-loop feedback to the front-end module, enabling the system's self-maintenance capability.

[0055] The overall system modules form a closed-loop data flow: in-situ capture by the gas acquisition module eliminates transmission delays; redundant design of the gas analysis module resists environmental failures; dynamic compensation by the correction module improves data accuracy; hierarchical response of the control module drives real-time actions; and optimized instruction feedback from the decision support module schedules resources. When implementing the gas logging method in a deep-sea pipeless drilling environment, the process includes: Step 1: Deploying in-situ capture and outputting bioelectric waveform signals; Step 2: Converting the waveform signals into digital concentration values; Step 3: Fusing the digital concentration values ​​and bottom-hole physical signals to generate corrected concentration and risk probability values; Step 4: Hierarchically triggering control commands and detection configuration instructions based on the risk probability values; Step 5: Integrating multi-well section data to output optimization instructions. During implementation, Step 1 responds to the output commands of Step 4 to adjust sampling behavior, and Step 3 responds to the output commands of Step 4 to adjust correction behavior, achieving millisecond-level anomaly response.

Claims

1. A gas logging system for deep-sea pipeless drilling and production environments, characterized in that, include: The gas acquisition module is deployed at the drilling wellhead to capture gas components in the drilling fluid underwater in situ and convert the captured gas into a bioelectric waveform signal output. The gas analysis module receives the bioelectric waveform signal output by the gas acquisition module and converts the bioelectric waveform signal into a digital concentration value for output. The calibration module receives the digital concentration value output by the gas analysis module and the real-time bottom hole physical signal input from the outside, and fuses the digital concentration value and the real-time bottom hole physical signal to generate a calibrated gas concentration and risk probability value output. The control module receives the risk probability value output by the correction module, responds to the received risk probability value to trigger a graded early warning signal and generate a control command output, and outputs a detection configuration instruction to the gas analysis module. The decision support module receives the corrected gas concentration and risk probability value of multiple well sections output by the correction module, as well as the equipment status information output by the correction module, and outputs drilling parameter optimization instructions after integration. The gas acquisition module receives the control command output by the control module to adjust the sampling behavior; The calibration module receives the detection configuration command output by the control module and adjusts the calibration behavior.

2. The gas logging system for deep-sea pipeless drilling and production environments according to claim 1, characterized in that, The gas acquisition module includes a dynamic membrane adjustment function, which receives wellbore pressure fluctuation data input, adjusts the electric field strength according to the wellbore pressure fluctuation data to change the membrane pore size, and improves the efficiency of gas capture; it uses the changed membrane pore size to capture gas components and outputs the bioelectric waveform signal.

3. The gas logging system for deep-sea pipeless drilling and production environments according to claim 2, characterized in that, The gas analysis module includes a redundant sensor array, receives the digital concentration value input, identifies when the hydrogen sulfide concentration in the digital concentration value exceeds a preset threshold, generates a switching command to shut down non-critical detection channels, and outputs a channel status flag reflecting the current detection channel status.

4. The gas logging system for deep-sea pipeless drilling and production environments according to claim 3, characterized in that, The correction module receives the drill string vibration spectrum signal, the digital concentration value output by the gas analysis module, and the real-time bottom hole physical signal from the outside; based on the drill string vibration spectrum signal, the digital concentration value, and the real-time bottom hole physical signal, it constructs a seepage state probability matrix, outputs the risk probability value, and selects the corresponding correction factor based on the seepage state probability matrix.

5. The gas logging system for deep-sea pipeless drilling and production environments according to claim 4, characterized in that, The control module receives the risk probability value output by the correction module; classifies the risk probability value; when the risk probability value exceeds a first threshold, it outputs a high-frequency sampling command to the gas acquisition module; when the risk probability value exceeds a second threshold, it outputs a lockout command to the blowout preventer system.

6. The gas logging system for deep-sea pipeless drilling and production environments according to claim 5, characterized in that, The decision support module receives the equipment status code output by the correction module; parses the equipment status code; and generates spare parts placement coordinates and drilling speed adjustment suggestions based on the parsing results.

7. The gas logging system for deep-sea pipeless drilling and production environments according to claim 6, characterized in that, The control module sends a channel shielding command to the gas analysis module; after receiving the channel shielding command, the gas analysis module shuts down at least one non-critical detection channel to reduce detection time and outputs the digital concentration value.

8. The gas logging system for deep-sea pipeless drilling and production environments according to claim 7, characterized in that, The correction module outputs a device fault marker to the decision support module; the decision support module generates device maintenance coordinates based on the device fault marker.

9. The gas logging system for deep-sea pipeless drilling and production environments according to claim 8, characterized in that, The gas acquisition module receives a high-frequency trigger command output by the control module; in response to the high-frequency trigger command, it switches to a millisecond-level continuous sampling mode, captures gas components, and outputs the bioelectric waveform signal; the decision support module receives the risk probability values ​​of multiple consecutive well sections output by the correction module. The risk probability values ​​of the multiple consecutive well sections are identified as increasing; in response to the identification results, mud density adjustment values ​​are output.

10. A gas logging method for deep-sea pipeless drilling and production environments, applied to the gas logging system for deep-sea pipeless drilling and production environments as described in any one of claims 1 to 9, characterized in that, include: Step 1: Deployed at the drilling wellhead location for underwater in-situ capture of gas components in drilling fluid and conversion of the captured gas into bioelectric waveform signal output; Step 2: Receive the bioelectric waveform signal output in Step 1, and convert the bioelectric waveform signal into a digital concentration value for output. Step 3: Receive the digital concentration value output from Step 2 and the real-time bottom hole physical signal input from the outside, and fuse the digital concentration value and the real-time bottom hole physical signal to generate a corrected gas concentration and risk probability value output. Step 4: Receive the risk probability value output in Step 3, respond to the received risk probability value to trigger a graded early warning signal and generate a control command output, and Step 4 outputs a detection configuration instruction to Step 2; Step 5: Receive the corrected gas concentration and risk probability value of multiple well sections output in Step 3, as well as the equipment status information output in Step 3, and output drilling parameter optimization instructions after integration. Step 1 receives the control command output in step 4 to adjust the sampling behavior; Step 3 receives the detection configuration command output in step 4 to adjust and correct the behavior.

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