Coal mine gas extraction system capability reasonable configuration and dynamic regulation and control method

Abstract

The invention relates to a coal mine gas extraction system capability reasonable configuration and dynamic regulation and control method, and belongs to the field of mine safety. The method comprises the following steps: S1, carrying out rationality evaluation on the installation capacity of the system on the basis of relevant parameters such as occurrence, extraction, tunneling and stoping; s2, pipe network laying rationality evaluation is carried out based on the extraction characteristics, the drilling scale and the pipeline parameters; s3, regulation and control priority index calculation and file division: firstly, for a system with the installation capacity and the pipe network laying being reasonably evaluated, obtaining priority index values of different regulation and control units of a to-be-regulated and controlled area according to a regulation and control priority index calculation model based on a pre-extraction standard reaching rate, an extraction tension degree and an extraction year-on-year growth rate index; secondly, matching different regulation and control gears according to a priority index result; and S4, regulating and controlling system parameter verification and instruction feedback. According to the method, reasonable configuration and dynamic regulation and control of the capacity of the gas extraction system under the negative pressure change response mechanism based on the drilling extraction efficiency are achieved, and interference or over-looseness of negative pressure configuration is avoided.

Description

Technical Field

[0001] The present invention belongs to the field of mine safety and relates to a method for reasonable configuration and dynamic regulation of the capacity of a coal mine gas drainage system. Background Art

[0002] High-gas and outburst-prone mines account for more than 50% of the total number of mines. Due to the relatively high gas content in these mines, special pumping stations need to be established for gas drainage work to ensure the safe production of the mines. During the process of the mining activities in the mine changing with the succession or the overall deployment being adjusted, key factors such as the rationality of the pipeline network laying of the drainage system, the matching degree of the system scale, and the magnitude of the negative pressure configuration at the drainage points need to be calculated and adjusted according to the service scope and the coal seam gas occurrence situation in the target area at different drainage stages. However, the current adjustment of the drainage system is not strictly calculated according to these factors. Especially in specific drainage areas and drainage stages, the configuration of the negative pressure at the drainage points has certain blindness and randomness, lacks scientific basis, and does not consider the dynamics.

[0003] In the current development stage that emphasizes high efficiency, high quality, and intelligence, it is particularly important to realize the on-demand, reasonable, and dynamic configuration and regulation of the drainage capacity of each drainage point of the drainage system based on the mining deployment of the mine, which is the key link to ensure the mine safety and drainage efficiency. At present, many scientific research institutions and enterprises have proposed corresponding solutions to this problem.

[0004] Guangli Technology Co., Ltd. proposed the "Method and System for Dynamic Optimization and Regulation of Coal Mine Gas Drainage" (CN201610797532.1). This method uses whether the rated negative pressure value of the pump group meets the sum of the actual negative pressure values in the drainage area as the basis for selecting the specific regulation logic. For the case where the rated negative pressure value meets the actual negative pressure value in the drainage area, it conducts discrimination and regulation based on gas pre-drainage, drainage while mining, and the rising speeds of the mixed drainage volume and pure drainage volume corresponding thereto. For the case where the rated negative pressure value is less than the actual negative pressure value in the drainage area, it directly regulates the pump group. This method proposes a regulation logic, but the regulation indicators are relatively single, without considering requirements in aspects such as mining deployment and drainage efficiency, and no clear quantification method is proposed after the start of regulation. China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd. proposed the "Intelligent Data Acquisition and Negative Pressure Distribution Regulation System and Method for Drainage Pipeline Network" (CN202210263378.5). This method mainly realizes the distribution regulation of negative pressure based on intelligent data acquisition of the drainage pipeline network and remote control of various valves in the drainage pipeline. This technology mainly focuses on the implementation level of hardware and methods during the regulation process of the drainage pipeline network, and does not involve technical requirements such as "where to regulate, when to regulate, and how much to regulate" for the drainage system capacity. China University of Mining and Technology (Beijing) proposed the "Intelligent Decision-making Regulation System and Method for Gas Drainage Pipeline Network" (CN202211060205.X), and Lu Jianxing of China University of Mining and Technology carried out the research on "Research and Development of Gas Drainage Parameter Field-Zone-Network Model and Intelligent Regulation System in Coal Mines", both of which proposed a drainage pipeline network calculation model based on the graph theory model. With the inlet flow rate and concentration of the pipeline network as characteristic constraint conditions and the valve opening as the decision variable, an intelligent decision-making and regulation model for gas drainage pipeline network is established. Relying on the intelligent decision-making and regulation model for gas drainage, the gas drainage of the pipeline network reaches the optimal; the above technologies are mainly proposed for verifying whether various parameters are optimal during the pre-regulation process before actual regulation based on the pipeline network calculation model. Shanghai Datun Energy Co., Ltd. Kongzhuang Coal Mine and North China Institute of Science and Technology proposed the "Dynamic Regulation System and Method for Mine Gas Drainage". This method first determines whether the safety constraint and efficiency constraint of the gas drainage system are met based on the relevant characteristic parameters of the gas drainage system collected. If not, the intelligent regulation process ends. If so, it conducts predictive modeling based on the ideal drainage characteristic curve obtained from historical data and outputs the regulation strategy, and then compares the actual result of the current regulation strategy with the predicted result and calculates the error; this technology gives the regulation strategy based on the drainage characteristic curve fitted from historical data, but the proposed drainage characteristic curve does not consider the dynamic changes of the connected boreholes, and the overall regulation process does not distinguish the drainage priority required to meet the mining succession.China University of Mining and Technology proposed "An Intelligent Regulation Experiment System and Method for Gas Drainage" (CN202410791203.0). This method builds an experimental platform that can simulate the flow of underground gas in the drainage system, obtains the influence of the drainability of coal seam gas and the degree of air leakage on the adjustment of drainage parameters. At the same time, through the signal analysis and processing subsystem and the monitoring and regulation subsystem, the opening of each electric control valve and the rotation speed of the drainage pump are adjusted to achieve the adjustment of gas concentration and pure flow under different working conditions. The drainage management platform takes the maximum pure gas flow of the main drainage pipe as the goal and solves to obtain the optimal system operation parameters. On the one hand, the application scenario of this technology is the laboratory simulation scenario, mainly to obtain the change laws of some parameters and states. On the other hand, this technology mainly focuses on the adjustment of the operation change of pump group parameters.

[0005] By consulting and analyzing relevant materials, it can be seen that the current related technologies focus on aspects such as the construction of regulation basis based on single-factor indicators, the verification of regulation strategies based on pipe network calculation models, and the experimental methods for regulating working condition parameters based on the operation characteristics of drainage pumps. No reasonable configuration and dynamic regulation method for the coal mine gas drainage system that comprehensively considers multiple factors such as mine excavation deployment, drainage characteristics of borehole groups, differences in drainage periods, and drainage efficiency has been retrieved. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a reasonable configuration and dynamic regulation method for the coal mine gas drainage system, and construct a set of procedures and methods that integrate the rationality evaluation of the drainage system, the reasonable configuration procedure of the drainage system capacity, the quantification method of the drainage system capacity configuration, and the regulation method of the drainage system capacity configuration, so as to realize the reasonable configuration and dynamic regulation of the gas drainage system capacity under the response mechanism of the negative pressure change based on the borehole drainage efficiency, and make the gas gushing and negative pressure configuration in the process of borehole drainage change with time reach a dynamically reasonable state, avoiding over-inflation or over-looseness of the negative pressure configuration.

[0007] To achieve the above purpose, the present invention provides the following technical solutions:

[0008] A method for reasonable allocation and dynamic regulation of the capacity of a coal mine gas drainage system. First, based on relevant parameters such as occurrence, drainage, tunneling, and coal mining, conduct a rationality assessment of the system's installed capacity, and verify the matching of the total amount to be drained and the system scale; second, based on drainage characteristics, borehole scale, and pipeline parameters, conduct a rationality assessment of pipeline network laying, and verify the matching of gas emission volume and pipeline network laying specifications; third, for a system with reasonable assessment of installed capacity and pipeline network laying, based on indicators such as pre-drainage compliance rate, drainage intensity, and growth rate of total drainage volume, calculate the drainage capacity allocation priority index for different states of the areas to be regulated respectively; fourth, construct a drainage volume prediction model with drainage points as the basic unit, considering the connection drainage time of borehole groups, the number of borehole groups, and the effective drainage footage; fifth, based on drainage negative pressure - compliance time - intensity, establish a regulation priority index grading interval and the negative pressure adjustment configuration ratio for the corresponding interval.

[0009] Specifically, it includes the following steps:

[0010] S1: Rationality assessment of the system's installed capacity: Based on relevant parameters such as occurrence, drainage, tunneling, and coal mining, conduct a rationality assessment of the system's installed capacity, and verify the matching of the total amount to be drained and the system scale;

[0011] The rationality assessment of the system's installed capacity is specifically to determine the expected minimum scale that the gas drainage system should possess according to the service range of the drainage system and the maximum drainage volume within the service cycle. Taking the expected minimum scale as the critical value, evaluate the capacity of the currently operating drainage system, and judge whether the total amount to be drained and the system scale match. If they do not match, it means that the installed capacity of the gas drainage system cannot meet the current gas drainage requirements of the mining and excavation deployment, and cannot ensure the balance of the drainage - tunneling - coal mining connection. It is necessary to specifically optimize the mining and excavation deployment, or expand the capacity of the drainage system, or improve the drainage process, or concentrate the drainage boreholes, etc.; if they match, proceed to the next link - the rationality assessment of pipeline network laying;

[0012] S2: Rationality assessment of pipeline network laying: Based on drainage characteristics, borehole scale, and pipeline parameters, conduct a rationality assessment of pipeline network laying, and verify the matching of gas emission volume and pipeline network laying specifications;

[0013] The rationality assessment of the pipeline network specifically refers to judging whether the specifications of the currently operating pipeline network are reasonable based on the gas emission volume at each drainage point, the average concentration that can be achieved by drainage, and the maximum economic flow rate. If they are not reasonable, it is necessary to optimize the unreasonable pipeline network specifications according to the assessment results; if they are reasonable, the first link of the dynamic regulation of the pipeline network drainage system capacity - the calculation and grading of the regulation priority index - can be entered;

[0014] S3: Calculation and grading of the regulation priority index:

[0015] First, for a system with reasonable evaluation of installation capacity and pipeline network laying, based on the pre-drainage compliance rate, drainage tension degree, and drainage year-on-year growth rate indicators, the priority index values of different regulation units in the area to be regulated are obtained according to the regulation priority index calculation model; secondly, different regulation gears are matched according to the priority index results. Each regulation gear corresponds to a quantization mechanism for negative pressure regulation configuration. Under the corresponding gear, unified regulation is carried out according to the priority index order of different regulation units and the corresponding negative pressure quantization configuration results. The final execution method of the regulation mechanism is the adjustment of the pipeline network valve opening; finally, a simulation regulation judgment of the valve opening is carried out in the pipeline network control and calculation system;

[0016] S4: Verification of regulation system parameters and instruction feedback: Use the results determined in the calculation and grading of the regulation priority index as the proposed regulation indicators for pre-regulation in the pipeline network control and calculation system. The adaptability of the pre-regulation parameters to the pipeline network is reflected through the calculation results. If not adaptable, adjust the regulation values recommended by the gear within the specified range; if adaptable, use the pre-adjusted values as regulation instructions to be sent to the valve controller to adjust the valves.

[0017] Furthermore, in step S3, the calculation and grading of the regulation priority index specifically include the following steps:

[0018] S31: Divide the coal seam area corresponding to the smallest regulation unit according to the service range of the drainage branch pipe;

[0019] S32: Calculate the gas pre-drainage compliance rate index of the coal seam areas corresponding to all the smallest regulation units. If the original value of the pre-drainage compliance rate = 0, the corresponding area is defined as the "planned drainage area", and the index takes 1; if the original value of the pre-drainage compliance rate is within the interval (0, 1), the corresponding area is defined as the "area being drained but not compliant", and the index takes 1; if the original value of the pre-drainage compliance rate = 1, the corresponding area is defined as the "area being drained and compliant", and the index takes 0; if the original value of the pre-drainage compliance rate is greater than 1, the corresponding area is defined as the "area where drainage should be carried out to the fullest extent after compliance", and the index takes 0;

[0020] S33: Calculate the extraction tension degree index for the areas defined as "planned extraction area" and "unqualified extraction area" in step S32. At the same time, the areas defined as "qualified extraction area" and "fully extracted area that should be extracted" enter the calculation link of the extraction year-on-year growth rate index. The original value of the extraction tension degree is defaulted to 0. For the areas that need to calculate the extraction tension degree index in this step, if the original value of the extraction tension degree = 0, only prompt the review result without calculating the index because this result will not occur after the evaluation of the system installation capacity and the rationality of pipeline network laying; if the original value of the extraction tension degree is within the interval (0, 1), the calculation result of the extraction tension degree index should change in the same direction as the original value of the extraction tension degree calculation, that is, the larger the original value of the extraction tension degree calculation, the larger the value of the extraction tension degree index. Further, the corresponding areas are all defined as "reasonable and affluent connection"; if the original value of the extraction tension degree = 1, use the aforementioned same-direction change calculation function to calculate the extraction tension degree index with the original value of the extraction tension degree = 1. Further, the corresponding areas are all defined as "reasonable and tense connection"; if the original value of the extraction tension degree is greater than 1, only prompt the review result without calculating the index because this result will not occur after the evaluation of the system installation capacity and the rationality of pipeline network laying;

[0021] S34: Calculate the extraction year-on-year growth rate index for the areas to be regulated. For the areas with equal index calculations mentioned above, conduct secondary division by calculating the extraction year-on-year growth rate index. The specific method is as follows: For the areas where the original value of the pre-extraction qualification rate calculation is within the interval (0, 1), that is, the "planned extraction area" and "unqualified extraction area" for which the extraction tension degree index has been calculated, if the original value of the extraction year-on-year growth rate = 0, only prompt the review result without calculating the index because this result will not occur after the evaluation of the system installation capacity and the rationality of pipeline network laying; if the original value of the extraction year-on-year growth rate is greater than 0, the calculation result of the extraction year-on-year growth rate index should change in the opposite direction to the original value of the extraction year-on-year growth rate calculation, that is, the smaller the original value of the extraction year-on-year growth rate calculation, the larger the value of the extraction year-on-year growth rate index. Further, the corresponding areas are all defined as "preferred allocation under the same conditions"; for the areas where the calculation result of the original value of the pre-extraction qualification rate is greater than or equal to 1, that is, the "qualified extraction area" and "fully extracted area that should be extracted", if the year-on-year growth rate original value = 0, do not calculate the index and close the valve to stop extraction. Further, the corresponding areas are all defined as "no extraction space"; if the year-on-year growth rate original value is greater than 0, the calculation result of the extraction year-on-year growth rate index should change in the opposite direction to the original value of the extraction year-on-year growth rate calculation, that is, the larger the original value of the extraction year-on-year growth rate calculation, the larger the value of the extraction year-on-year growth rate index. Further, the corresponding areas are all defined as "having extraction space";

[0022] S35: Calculate the comprehensive control priority index by weighted average of the pre-drainage compliance rate index, drainage intensity index, and year-on-year drainage growth rate index calculated for the area where the pre-drainage compliance rate is in the interval (0, 1); since the pre-drainage compliance rate index and drainage intensity index are both 0 for the area where the pre-drainage compliance rate is greater than or equal to 1, only the year-on-year drainage growth rate index is calculated, and the calculation method of the comprehensive control priority index for this type of area is the year-on-year drainage growth rate index multiplied by the corresponding weight.

[0023] Furthermore, in step S3, the calculation of the pre-drainage compliance rate, drainage intensity, and year-on-year drainage growth rate is directly or indirectly related to the drainage volume prediction model constructed based on the connection drainage time of the drilling group, the number of drilling groups, and the effective drainage footage; related to the drainage volume prediction model;

[0024] The drainage volume prediction model is used to predict the instantaneous cumulative volume of the control unit at any time and different drainage footages, and the model expression is: In the formula, q(t) is the drainage characteristic model of the control minimum unit on the t-th day after connecting the i-th group of drill holes, and t i is the connection time of the i-th group of drill holes, and this model is obtained based on the investigation of drill holes with a hundred-meter effective drainage footage; n represents the number of drill hole groups.

[0025] Furthermore, in step S3, the calculation model of the pre-drainage compliance rate η is:

[0026]

[0027] In the formula, t 临界 is the critical time for the drainage in the corresponding area of the control minimum unit to reach compliance during reasonable connection, and Q 临界 (t 临界 ) is the critical drainage volume corresponding to the critical time for the drainage in the corresponding area of the control minimum unit to reach compliance, and Q(t′) is the total drainage volume at the time of drainage to t′, which is obtained by statistical measurement of the metering device.

[0028] Furthermore, in step S3, the calculation model of the drainage intensity ξ is: t 规划 is the planned drainage time for the corresponding area of the control minimum unit during reasonable connection, and t 临界 is the critical time for the drainage in the corresponding area of the control minimum unit to reach compliance during reasonable connection.

[0029] Furthermore, in step S3, the calculation model of the original value ε of the year-on-year drainage growth rate is:

[0030]

[0031] The substitution value ε′ of the index calculation is ε′ = f(ε), Where f(ε) is a function that maps ε′ to the interval [0, 1], Q(t2′) is the total gas extraction volume when the extraction of the corresponding area of the minimum regulation unit reaches t2′, and Q(t1′) is the total gas extraction volume when the extraction of the corresponding area of the minimum regulation unit reaches t1′.

[0032] The beneficial effects of the present invention are as follows: In the method of the present invention, the construction of the gas extraction system in the mine is adapted to the gas occurrence in the coal seam of the mine, the mining and excavation deployment, and the gas extraction plan. When there are no major adjustments in the gas occurrence in the coal seam, the mining and excavation deployment, and the gas extraction plan, the total gas extraction capacity of the gas extraction system basically will not change significantly. The adjustable space and links of the gas extraction system are based on the response mechanism of the borehole gas extraction efficiency to the negative pressure change on the premise that the installed capacity of the system and the pipeline laying meet the requirements, so that the gas emission and the negative pressure configuration reach a dynamic reasonable configuration during the process of borehole gas extraction changing with time, avoiding over-inflation or over-looseness of the negative pressure configuration.

[0033] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0035] Figure 1 is the overall framework diagram of the method for reasonable configuration and dynamic regulation of the gas extraction system capacity in the coal mine of the present invention;

[0036] Figure 2 is the detailed flowchart of the method for reasonable configuration and dynamic regulation of the gas extraction system capacity in the coal mine of the present invention;

[0037] Figure 3 is the specific flowchart for determination and division of the regulation area. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following illustrates the embodiments of the present invention through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0039] Please refer to Figures 1 to 3 , an embodiment of the present invention provides a method for reasonable configuration and dynamic regulation of the capacity of a coal mine gas drainage system. Assume that the area corresponding to the smallest unit to be regulated consists of 6 areas, namely areas A, B, C, D, E, and F. The gas drainage characteristic model of the boreholes with effective drainage footage per 100 meters in each area satisfies q(t) = 0.02e -0.001t . The total number of borehole groups connected to the drainage branch pipes in each area is 4 groups, the effective drainage footage of each group is 100 m, and the connection frequency of the borehole groups is 5 days. The critical drainage times obtained based on the drainage characteristic model, the required drainage volume for reaching the standard, and the original gas occurrence in the area are t 临界1 = 150, t 临界2 = 120, t 临界3 = 100, t 临界4 = 90, t 临界5 = 80, t 临界6 = 70, and the corresponding critical drainage volumes are Q 临界1 = 5, Q 临界2 = 7, Q 临界3 = 3, Q 临界4 = 2, Q 临界5 = 5, Q 临界6 = 6. The drainage times based on the mining and excavation deployment plan are t 规划1 = 160, t 规划2 = 120, t 规划3 = 120, t 规划4 = 100, t 规划5 = 90, t 规划6 = 80. The current actual drainage times are t 实际1 = 120, t 实际2 = 100, t 实际3 = 80, t 实际4 = 90, t 实际5 = 100, t 实际6 = 90, and the corresponding on-line metered drainage volumes are Q 实际1 = 3, Q 实际2 = 5, Q 实际3 = 2, Q 实际4 = 1, Q 实际5 = 8, Q 实际6 = 7. The weight ratios ω1, ω2, and ω3 of the drainage tension degree and the year-on-year growth rate are 5%, 90%, and 5% respectively. The negative pressure and drainage volume in different drainage periods satisfy The total configurable negative pressure is p 总 .

[0040] As Figure 1 and Figure 2 shown, the main steps of implementing this method are as follows:

[0041] Step 1: Rationality assessment of the system installation capacity.

[0042] Refer to the "Design Standard for Mine Gas Drainage Engineering" (GB50471-2018) or other relevant effective methods to calculate the maximum drainage scale within the service scope and service cycle of the drainage system, and obtain the maximum pure drainage volume Q that can be achieved during the drainage process. 纯 , and calculate the maximum drainage mixture volume Q based on the average gas drainage concentration C% of the corresponding system at the current stage. 混 = Q 纯 / C%, compare the calculated maximum drainage mixture volume Q 混 with the installed capacity Q of the pump unit 装机 . If Q 混 > Q 装机 , it indicates that the installed capacity is insufficient, and it is necessary to optimize the mining and excavation deployment, expand the drainage system capacity, improve the drainage process, or concentrate the drainage boreholes, etc. If Q 混 ≤Q 装机 , it indicates that the installed capacity meets the requirements. Assuming that the installed capacity of the mine drainage system meets the requirements, proceed to the next link.

[0043] Step 2: Rationality assessment of pipeline laying.

[0044] Based on the drainage characteristics model of the boreholes with an effective advance of 100 meters in the area and the instantaneous cumulative volume calculation model with the borehole group as the incremental control unit, calculate the maximum instantaneous cumulative volume of each area, as shown in the following formula. It can be calculated that the maximum instantaneous cumulative volume is 0.08 m 3 / min.

[0045]

[0046] Based on the average gas drainage concentration of 80% of the corresponding borehole group at the current stage, the maximum drainage mixture flow rate of the drainage branch pipe can be calculated as 0.08 / (80%) = 0.1 m 3 / min. Combine with the pipeline selection method in the "Design Standard for Mine Gas Drainage Engineering" (GB50471-2018) to calculate the corresponding minimum pipe diameter specification d at the economic flow rate min , and then compare it with the actual pipeline network specification d 实际 . If d min > d 实际 , it indicates that the pipeline specification does not meet the requirements, and it is necessary to optimize the pipeline network accordingly. If d min ≤d 实际 , it indicates that the pipeline specification meets the requirements, and this calculation meets the requirements, then proceed to the next link.

[0047] Step 3: Calculation and grading of the regulation priority index, as Figure 3 shown.

[0048] The first small step: Division of the corresponding area of the minimum control unit. Divide the coal seam area corresponding to the minimum control unit according to the service range of the extraction branch pipe; The second small step: Calculation of the pre-extraction compliance rate. Substitute the relevant data into the formula It can be calculated that η1 = 0.600, η2 = 0.714, η3 = 0.667, η4 = 0.500, η5 = 1.600, η6 = 1.167. Then, A, B, C, and D are "areas where extraction is in progress but not yet compliant", and the index takes the value of 1. E and F are "areas where extraction is in progress and already compliant", and the index takes the value of 0; The third small step: Calculation of the extraction intensity. For the "areas where extraction is in progress and already compliant" E and F, they directly enter the calculation link of the year-on-year growth rate of extraction. For the "areas where extraction is in progress but not yet compliant" A, B, C, and D, calculate the extraction intensity. Substitute the relevant data into the formula It can be calculated that ξ1 = 0.938, ξ2 = 1.000, ξ3 = 0.833, ξ4 = 0.900; The fourth small step: Calculation of the year-on-year growth rate of extraction. First, substitute the relevant data into the formula Calculate the original value of the year-on-year growth rate. The extraction volume is the extraction increment from 10 to 40 days after the actual extraction time in each area. The specific results of the year-on-year increment of the extraction volume are as follows:

[0049]

[0050] The original value of the extraction growth rate ε1 = 0.070, ε2 = 0.071, ε3 = 0.073, ε4 = 0.072, ε5 = 0.071, ε6 = 0.072. The substitution value for index calculation ε1′ = f(ε1) = 0.039, ε2′ = f(ε2) = 0.043, ε3′ = f(ε3) = 0.047, ε4′ = f(ε4) = 0.045, ε5′ = f(ε5) = 0.043, ε5′ = f(ε5) = 0.045. The fifth small step: Calculation of the comprehensive index of control priority. The specific calculation method is index = η×ω1 + ξ×ω2 + ε×ω3. The results are: index1 = 0.8957, index2 = 0.9522, index3 = 0.8024, index4 = 0.8623, index5 = 0.0022, index6 = 0.0023.

[0051] Step 6: Regulate the priority index grading and calculate the recommended values of corresponding regulation parameters. According to the actual situation of the mine, the regulation priority comprehensive index 0 ≤ index < 0.1 is divided into the first grade, which is the regulation grade for the area where the pre-drainage compliance rate ≥ 1; the regulation priority comprehensive index 0.1 ≤ index < 0.4 is divided into the second grade; the regulation priority comprehensive index 0.4 ≤ index < 0.6 is divided into the third grade; the regulation priority comprehensive index 0.6 ≤ index < 0.8 is divided into the fourth grade; the regulation priority comprehensive index 0.8 ≤ index < 1 is divided into the fifth grade. The second, third, fourth, and fifth grades are the regulation grades for the area where the pre-drainage compliance rate < 1. The negative pressure quantization configuration mechanism corresponding to different regions in each grade is determined by the relationship between the negative pressure and the drainage volume in different periods of drainage. Assume that according to the relationship The negative pressure configuration results considering only the drainage time factor are p i , i = 1 to 6. The recommended values of negative pressure configuration corresponding to different regions in each grade are calculated as shown in the following formula. Finally, the recommended values of negative pressure configuration are calculated using the following formula. The calculation results of each index item are shown in Table 1 below.

[0052]

[0053] Table 1 Calculation results of each index item

[0054]

[0055] Step 4: Verify the regulation system parameters and give instruction feedback. Take the results determined in the calculation and grading of the regulation priority index as the proposed regulation indicators for pre-regulation in the drainage control and calculation system. The adaptability of the pre-regulation parameters to the pipeline network is reflected by the calculation results. If they are not adaptable, adjust the regulation values recommended for the grade within the specified range. If they are adaptable, send the pre-adjusted values as regulation instructions to the valve controller to adjust the valves. The valve opening adjustment mechanism is established based on the relationship model between the opening of valves of different specifications and the pipeline negative pressure obtained through experiments.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A method for reasonable configuration and dynamic control of coal mine gas extraction system capacity, characterized in that: The method specifically comprises the following steps: S1: Evaluation of the rationality of system installed capacity: Based on the relevant parameters of occurrence, extraction, excavation and mining, the rationality of system installed capacity is evaluated to determine the matching between the total amount to be extracted and the system scale; The rationality assessment of the system installed capacity is to determine the estimated minimum scale that the drainage system should have based on the service scope of the drainage system and the maximum drainage volume within the service period, and to evaluate the capacity of the currently operating drainage system with the estimated minimum scale as the critical value to determine whether the total amount to be extracted matches the system scale. If not, it means that the installed capacity of the drainage system cannot meet the gas drainage demand of the current mining deployment, and cannot ensure the balance of extraction-excavation-extraction connection. It is necessary to optimize the mining deployment or expand the capacity of the drainage system or improve the drainage process or increase the concentration of the drainage drilling. If it matches, proceed to the next link - rationality assessment of pipeline network laying. S2: Pipeline network laying rationality assessment: Based on the extraction characteristics, drilling scale and pipeline parameters, the rationality of the pipeline network laying is assessed to verify the matching between the gas emission volume and the pipeline network laying specifications; The rationality assessment of the pipeline network specifically refers to judging whether the specifications of the current operating pipeline network are reasonable based on the outflow volume of each extraction point, the average concentration that can be achieved by extraction, and the maximum economic flow rate as basic indicators. If it is not reasonable, it is necessary to optimize the unreasonable pipeline network specifications based on the evaluation results; if it is reasonable, it can enter the first link of dynamic regulation of the pipeline network extraction system capacity - calculation and classification of the regulation priority index; S3: Calculation and classification of control priority index: Firstly, for the system with reasonable installed capacity and pipeline network laying evaluation, based on the pre-pumping compliance rate, extraction intensity and extraction year-on-year growth rate indicators, the priority index values ​​of different control units in the area to be regulated are obtained according to the control priority index calculation model; secondly, different control gears are matched according to the priority index results. Each control gear corresponds to a quantitative mechanism of negative pressure regulation configuration. Under the corresponding gear, unified regulation is carried out according to the priority index sequence of different control units and the corresponding negative pressure quantitative configuration results. The final execution mode of the control mechanism is the adjustment of the valve opening of the pipeline network; finally, the simulation control judgment of the valve opening is carried out in the pipeline network control and solution system; S4: Verification of control system parameters and instruction feedback: The results determined in the control priority index calculation and the gear division are used as the proposed control indicators for pre-control in the pipeline control and solution system. The solution results reflect the compatibility of the pre-control parameters with the pipeline network. If they are not compatible, the control value recommended by the gear position is adjusted within the specified range; if they are compatible, the pre-adjusted value is sent to the valve controller as a control instruction to adjust the valve.

2. The method for reasonable configuration and dynamic control of coal mine gas extraction system capacity according to claim 1 is characterized in that: In step S3, the control priority index calculation and file division specifically include the following steps: S31: Divide the coal seam area corresponding to the minimum control unit according to the service range of the extraction branch pipe; S32: Calculate the gas pre-extraction compliance rate index of the coal seam area corresponding to all minimum control units. If the original value of the pre-extraction compliance rate = 0, the corresponding area is defined as the "planned extraction area" and the index is 1; if the original value of the pre-extraction compliance rate is between the interval (0, 1), the corresponding area is defined as the "area that is being extracted but not meeting the standard" and the index is 1; if the original value of the pre-extraction compliance rate = 1, the corresponding area is defined as the "area that is being extracted and has met the standard" and the index is 0; if the original value of the pre-extraction compliance rate is greater than 1, the corresponding area is defined as the "area that has met the standard and should be exhausted" and the index is 0; S33: Calculate the extraction tension index for the areas defined as "planned extraction area" and "extraction area that does not meet the standard" in step S32. At the same time, the areas defined as "extraction area that has met the standard" and "extraction area that has met the standard" enter the extraction year-on-year growth rate index calculation link, and the original value of the extraction tension is 0 by default. For the area where the extraction tension index needs to be calculated in this step, if the original value of the extraction tension = 0, only the review result is prompted without calculating the index; if the original value of the extraction tension is between the interval (0, 1), the calculation result of the extraction tension index should change in the same direction as the original value of the extraction tension calculation, that is, the larger the original value of the extraction tension calculation, the larger the extraction tension index value, and the corresponding areas are further defined as "connected and reasonable and rich"; if the original value of the extraction tension = 1, the extraction tension index with the original value of the extraction tension = 1 is calculated using the same direction change calculation function, and the corresponding areas are further defined as "connected and reasonable and tight"; if the original value of the extraction tension is greater than 1, only the review result is prompted without calculating the index; S34: Calculate the year-on-year growth rate index of extraction in the area to be regulated, and divide the areas with the same calculated index into two parts by calculating the year-on-year growth rate index of extraction. The specific method is as follows: for the areas where the original value of the pre-extraction compliance rate is between the interval (0, 1), that is, the "planned extraction area" and "extraction non-compliance area" where the extraction tension index is calculated, if the original value of the year-on-year growth rate of extraction = 0, only the review result is prompted without calculating the index; if the original value of the year-on-year growth rate of extraction is greater than 0, the calculation result of the year-on-year growth rate index of extraction should change inversely with the original value of the year-on-year growth rate of extraction, that is, the smaller the original value of the year-on-year growth rate of extraction is, the higher the year-on-year growth rate of extraction is. The larger the value of the growth rate index is, the corresponding area is further defined as "priority allocation under the same conditions"; for areas where the original value of the pre-pumping compliance rate is greater than or equal to 1, that is, "areas that have met the standards in the process of pumping" and "areas that have met the standards and should be pumped as much as possible", if the original value of the year-on-year growth rate is 0, the index is not calculated and the valve is closed and pumping is stopped, and the corresponding areas are further defined as "no pumping space"; if the original value of the year-on-year growth rate is greater than 0, the calculation result of the year-on-year growth rate index of the extraction should change in the opposite direction to the original value of the year-on-year growth rate calculation of the extraction, that is, the larger the original value of the year-on-year growth rate calculation of the extraction, the larger the value of the year-on-year growth rate index of the extraction, and the corresponding areas are further defined as "there is pumpable space"; S35: Calculate the control priority comprehensive index by weighted average of the pre-pumping compliance rate index, extraction tension index and extraction year-on-year growth rate index calculated for regions where the pre-pumping compliance rate is between the interval (0, 1); since the pre-pumping compliance rate index and extraction tension index for regions where the pre-pumping compliance rate is greater than or equal to 1 are both 0, only the extraction year-on-year growth rate index is calculated, and the control priority comprehensive index for this type of region is calculated by multiplying the extraction year-on-year growth rate index by the corresponding weight.

3. The method for reasonable configuration and dynamic control of coal mine gas extraction system capacity according to claim 1 or 2, characterized in that: In step S3, the calculation of the pre-pumping compliance rate, the degree of pumping intensity and the year-on-year growth rate of pumping are directly or indirectly related to the pumping volume prediction model constructed based on the drilling group pumping time, the number of drilling groups and the effective pumping footage; the pumping volume prediction model is related; The extraction volume prediction model is used to predict the instantaneous cumulative volume of the control unit at any time and with different extraction depths. The model expression is: Where q(t) is the drainage characteristic model of the smallest unit controlled on the tth day after the i-th group of boreholes are connected, t i is the access time of the i-th group of drilling holes, and n represents the number of drilling groups.

4. The method for reasonable configuration and dynamic control of coal mine gas extraction system capacity according to claim 3 is characterized in that: In step S3, the calculation model of the pre-pumping standard-reaching rate η is: Where, t 临界 In order to reasonably adjust the critical time for the minimum unit corresponding to the area to reach the standard, Q 临界 (t 临界 ) is the critical extraction volume corresponding to the critical time for the extraction of the corresponding area of ​​the smallest unit to meet the standard, and Q(t′) is the total extraction volume at t′, which is obtained by the metering device.

5. The method for reasonable configuration and dynamic control of coal mine gas extraction system capacity according to claim 3 is characterized in that: In step S3, the calculation model of the extraction intensity ξ is: t 规划 In order to reasonably connect the minimum unit and the corresponding area planning extraction time, t 临界 In order to achieve reasonable connection, the critical time for the minimum unit corresponding to the area to achieve extraction standards is adjusted.

6. The method for reasonable configuration and dynamic control of coal mine gas extraction system capacity according to claim 3 is characterized in that: In step S3, the calculation model of the original value of the year-on-year growth rate ε is: Index calculation Substitute the value ε′=f(ε), Where f(ε) is the function that maps ε′ to the interval [0,1], Q(t2′) is the total amount of extraction from the area corresponding to the minimum control unit to t2′, and Q(t1′) is the total amount of extraction from the area corresponding to the minimum control unit to t1′.

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