CN-121976198-A - Buried PCCP cathodic protection and stray current interference cooperative prevention and control system and method

CN121976198ACN 121976198 ACN121976198 ACN 121976198ACN-121976198-A

Abstract

The invention relates to the technical field of pipeline corrosion protection, in particular to a buried PCCP cathodic protection and stray current interference cooperative prevention and control system and method. The system comprises a corrosion environment and interference source comprehensive evaluation module, a cathode protection optimization design module, a stray current cooperative drainage module and an intelligent monitoring and operation management module. According to the invention, the quantitative fusion evaluation of static environment corrosiveness and dynamic interference risk is realized by coupling and weighting the key parameters and grading evaluation of dynamic stray current, an automatically-adjusted response mechanism is established, the hydrogen embrittlement risk of the prestressed steel wire is blocked from an electrochemical source by combining a high-precision Dlight formula for introducing filler correction and mirror effect correction, and meanwhile, dynamic optimization is performed through synchronous on-off test, so that the deep synergy and active adaptation of two systems of cathodic protection and stray current drainage are realized, and the two systems are converted from mutual interference into synergy.

Inventors

LU YUNCAI
LUO WEIBANG
SUN ZHAOBIN
CHEN ZHENJUN
LI JIALUN

Assignees

新疆水利水电勘测设计研究院有限责任公司
青龙管业集团股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260318

Claims (10)

1. The utility model provides a buried PCCP cathodic protection and stray current interference are prevention and control system in coordination which characterized in that includes: The comprehensive evaluation module of the corrosion environment and the interference source is used for carrying out multi-parameter corrosiveness evaluation on soil and water environment along the buried prestress steel cylinder concrete pipeline, carrying out grading quantitative evaluation on direct current and alternating current stray current interference suffered by the pipeline, and outputting an evaluation result; The cathode protection optimization design module is used for communicating and receiving the evaluation result of the corrosion environment and interference source comprehensive evaluation module, and generating an optimized sacrificial anode configuration parameter, an optimized potential control scheme and a guarantee scheme of pipeline electric connection technical specifications by combining the hydrogen embrittlement sensitivity of the prestressed steel wire; The stray current cooperative drainage module is cooperated with the corrosion environment and interference source comprehensive evaluation module and the cathode protection optimization design module, selects a corresponding drainage mode according to the interference evaluation level in the evaluation result, and generates a drainage scheme compatible with the guarantee scheme in terms of spatial layout and electrical parameters, wherein the compatibility is represented by controlling the cathode protection current loss rate to be lower than 5%; The intelligent monitoring and operation and maintenance management module integrates the sensing network of the Internet of things, a data analysis algorithm and a decision support function, and is used for monitoring the running state in real time, diagnosing abnormality, early warning faults and implementing predictive maintenance decisions based on the equipment state.
2. The system for co-controlling and co-protecting the cathode protection and the stray current interference of the buried PCCP according to claim 1, wherein the comprehensive evaluation module for the corrosive environment and the interference source comprises: The water and soil corrosiveness multi-index coupling evaluation unit is configured to collect and analyze key parameters of Cl - content, pH value, oxidation-reduction potential, soil resistivity and polarized current density, calculate a comprehensive grading value through a weighted grading method, automatically judge a strong corrosion environment and trigger a forced cathodic protection mechanism when the comprehensive grading value S is more than or equal to 3.0; The stray current interference grading evaluation unit is configured to monitor the deviation condition of the ground potential of the pipe relative to the natural potential, takes the potential forward deviation not less than 100mV and the accumulated time duty ratio of the deviation state as a direct current grading index, and simultaneously, measures the alternating current density of the surface of the pipe and automatically sorts the alternating current density as an alternating current grading index, wherein the grading index comprises: the current density <30A/m 2 is weak interference, the current density less than or equal to 30 is less than or equal to 100A/m 2 is medium interference, and the current density >100A/m 2 is strong interference.
3. The buried PCCP cathodic protection and stray current interference cooperative prevention and control system as set forth in claim 2, wherein the soil and water corrosiveness multi-index coupling evaluation unit samples at not less than 2 measuring points per kilometer along the pipeline, and comprises: Measuring Cl - content by a molar method, measuring pH value by a glass electrode potential method, measuring oxidation-reduction potential based on the response of an inert electrode to oxidation-reduction pairs in the solution, measuring soil resistivity by a quadrupole method, and measuring polarized current density by a Linear Polarization Resistance (LPR) technology; When the parallel distance between the pipeline and the high-voltage alternating current line is less than 100m, continuous potential monitoring is carried out for 24 hours, and a stray current distribution map is drawn.
4. The co-protection and control system for buried PCCP cathodic protection and stray current interference according to claim 1, wherein said cathodic protection optimization design module comprises: the hydrogen embrittlement constraint potential control unit is configured to limit the polarization potential safety interval of the prestressed steel wire to be between-1000 mV and-850 mV, and is provided with an automatic monitoring and regulating mechanism, and when the potential is continuously negative to-1000 mV for more than 1 hour, the potential regulating device is automatically started to pull the potential back to the safety interval; the sacrificial anode configuration optimizing unit calculates anode grounding resistance by adopting a correction Dright formula which introduces shielding effect coefficients among a plurality of anodes; The standardized design unit for electric connection of pipelines is characterized in that the connection between the prestressed steel wires and the steel cylinders is provided with galvanized flat steel strips with the length of 50mm multiplied by 1.5mm, the galvanized flat steel strips are connected in a spot welding mode, the distance between welding spots is not more than 500mm, the single-point connection resistance is not more than 0.03 omega, the bridging between pipe sections is provided with a 1 multiplied by 25mm 2 XLPE/PVC insulated copper core cable, and the bridging point resistance is not more than 0.01 omega.
5. The co-protection and control system for buried PCCP cathodic protection and spurious current interference according to claim 4, wherein said sacrificial anode configuration optimizing unit comprises: firstly, calculating the grounding resistance of the single vertical sacrificial anode: ; Wherein, the The vertical sacrificial anode is grounded; Is soil resistivity; is the length of the bare sacrificial anode; sacrificial anode diameter for prepackaging; the distance from the center of the sacrificial anode to the ground; the resistivity of the filler is; Is the equivalent diameter of the bare sacrificial anode.
6. And calculating the grounding resistance of the two-branch horizontal sacrificial anode: ; Wherein, the A horizontal sacrificial anode ground resistance; Is soil resistivity; is the length of the bare sacrificial anode; sacrificial anode diameter for prepackaging; the distance from the center of the sacrificial anode to the ground; the resistivity of the filler is; Is the equivalent diameter of the bare sacrificial anode.
7. The co-protection and control system for buried PCCP according to claim 1, wherein the co-drainage module for stray current comprises: the direct current drainage strategy selection unit executes a grading response strategy according to the grading index of the stray current interference grading evaluation unit, and comprises the following steps: For weak interference, direct grounding drainage is adopted, and the grounding resistance is required to be less than or equal to 10Ω; for medium interference, a polar drainer is adopted for drainage, the drainer adopts a Schottky diode, the reverse withstand voltage is more than or equal to 200V, the forward voltage drop is less than or equal to 1V, and the rated current is calculated according to an I_drainage= (V_interference-V_reverse)/R_grounding formula; For strong interference, forced drainage is adopted, the constant potential instrument is used for controlling, the output current is 0-50A and is adjustable, and the potential control precision is +/-0.01V; an alternating current drainage device configuration unit, wherein a solid-state decoupling device is arranged in a region with a grading index of more than medium; and the compatibility control unit is used for realizing dynamic optimization through synchronous on-off test and balancing the optimal drainage effect and the minimum protection interference.
8. The cooperative prevention and control system for cathodic protection and stray current interference of a buried PCCP according to claim 6, wherein the synchronous on-off test in the compatibility control unit comprises the following steps: (1) Measuring and recording a protection potential reference value of each test pile of the pipeline under the closing state of the drainage equipment; (2) Starting drainage equipment, and measuring the potential of each test pile again after the drainage equipment stably operates for 30 minutes; (3) Calculating potential variation delta V= |V opening-V closing|, and if delta V of any test pile is more than 50mV, adjusting the working point or the grounding resistance of the drainage device; (4) Repeating the steps (1) - (3) until the delta V of all the test piles is less than or equal to 50mV and the parameter variation of the cathodic protection system is within the allowable range.
9. The co-protection and control system for buried PCCP cathodic protection and stray current interference according to claim 1, wherein said intelligent monitoring and operation management module comprises: The LoRaWAN wireless sensing network consists of intelligent test piles which are arranged at intervals of 200-500m along a pipeline, each test pile integrates a high-impedance potential probe, a current sensor, a temperature sensor and a 4G/LoRa dual-mode communication unit, and the data sampling frequency can be remotely configured within the range of 1-60 minutes; The self-adaptive fault diagnosis unit is used for calculating performance indexes of potential fluctuation rate, anode current attenuation rate and earth resistance annual growth rate in real time, and triggering three-level early warning according to severity when any performance index exceeds a threshold value; The anode residual life prediction model dynamically predicts the residual life of each anode by using historical and real-time current data, and can automatically generate a work order to be pushed to the mobile terminal of the operation and maintenance personnel for early warning before the life is exhausted.
10. A buried PCCP cathodic protection and stray current interference cooperative prevention and control method applied to the buried PCCP cathodic protection and stray current interference cooperative prevention and control system according to any one of claims 1 to 8, characterized by comprising the following steps: S1, carrying out multi-parameter corrosiveness evaluation on soil and water environment along a buried prestress steel cylinder concrete pipeline through a corrosion environment and interference source comprehensive evaluation module, carrying out grading quantitative evaluation on direct current and alternating current stray current interference suffered by the pipeline, and outputting an evaluation result; s2, receiving an evaluation result through a cathodic protection optimal design module, and generating an optimized sacrificial anode configuration parameter, an electric potential control scheme and a guarantee scheme of pipeline electric connection technical specifications by combining the hydrogen embrittlement sensitivity of the prestressed steel wire; S3, a stray current cooperative drainage module, the corrosion environment and interference source comprehensive evaluation module and the cathode protection optimization design module cooperate to select a corresponding drainage mode according to an interference evaluation level in an evaluation result, and a drainage scheme compatible with the guarantee scheme in terms of spatial layout and electrical parameters is generated; S4, integrating the intelligent monitoring and operation management module with the sensing network of the Internet of things, a data analysis algorithm and a decision support function, and being used for monitoring the running state in real time, diagnosing abnormality, early warning faults and implementing predictive maintenance decisions based on the equipment state.

Description

Buried PCCP cathodic protection and stray current interference cooperative prevention and control system and method Technical Field The invention relates to the technical field of pipeline corrosion protection, in particular to a buried PCCP cathodic protection and stray current interference cooperative prevention and control system and method. Background PCCP is widely applied to large-scale diversion projects due to high bearing capacity and economy, however, as shown in figure 3, a macro battery formed by a steel cylinder, a prestressed steel wire, a cement mortar protection layer and soil electrolyte is adopted, steel components (the steel cylinder and the prestressed steel wire) in the structure form a corrosion battery in a buried complex environment due to the soil electrolyte, and the corrosion is accelerated due to the interference of stray current generated by subways, electrified railways, high-voltage transmission lines and the like, so that the structural integrity and the operation safety of a pipeline are seriously threatened; However, when co-controlling buried PCCP cathodic protection and stray current interference, there are the following drawbacks: Firstly, the cathode protection system and the stray current drainage system are usually guided by different specifications, are completed in different design stages and are implemented by different construction units, and can generate conflict on physical space and an electric loop, for example, a drainage grounding electrode can "steal" cathode protection current, so that the protection efficiency is reduced (the current flow is abnormal by more than 10 percent) to form a protection blind area, otherwise, the cathode protection system can also influence the drainage effect, so that the protection blind area is frequent; Secondly, whether the cathodic protection potential meets the standard is mainly focused at present, a quantitative evaluation method for dynamic and multi-source stray current interference is lacking, an evaluation model for coupling environmental corrosiveness and interference risks is lacking, meanwhile, a prestressed steel wire in PCCP is high-strength steel and is extremely sensitive to hydrogen embrittlement, and if the cathodic protection is pursued for a 'more negative and better' protection potential, the potential is extremely easy to be subjected to minus 1000mV (CSE) for a long time, so that a large number of hydrogen atoms infiltrate into the steel wire to cause Hydrogen Induced Cracking (HIC), and catastrophic brittle fracture is caused; Thirdly, relying on manual periodic inspection (usually in units of months or quarters), data acquisition is discontinuous, fault discovery is delayed (response time is often more than 24 hours), and fault early warning and predictive maintenance based on equipment states cannot be achieved. In view of this, we propose a buried PCCP cathodic protection and spurious current interference co-control system and method. Disclosure of Invention The invention aims to provide a buried PCCP cathodic protection and stray current interference cooperative prevention and control system and method, which are used for solving the problems in the background art. In order to achieve the above object, one of the objects of the present invention is to provide a cooperative prevention and control system for cathode protection and stray current interference of a buried PCCP, comprising: The comprehensive evaluation module of the corrosion environment and the interference source is used for carrying out multi-parameter corrosiveness evaluation on soil and water environment along the buried prestress steel cylinder concrete pipeline, carrying out grading quantitative evaluation on direct current and alternating current stray current interference suffered by the pipeline, and outputting an evaluation result; The cathode protection optimization design module is used for communicating and receiving the evaluation result of the corrosion environment and interference source comprehensive evaluation module, and generating an optimized sacrificial anode configuration parameter, an optimized potential control scheme and a guarantee scheme of pipeline electric connection technical specifications by combining the hydrogen embrittlement sensitivity of the prestressed steel wire; The stray current cooperative drainage module is cooperated with the corrosion environment and interference source comprehensive evaluation module and the cathode protection optimization design module, selects a corresponding drainage mode according to the interference evaluation level in the evaluation result, and generates a drainage scheme compatible with the guarantee scheme in terms of spatial layout and electrical parameters, wherein the compatibility is represented by controlling the cathode protection current loss rate to be lower than 5%; The intelligent monitoring and operation and maintenance management module integrates the se