Method and system for determining distance between poisonous gas leakage and railway safety protection

Abstract

The invention discloses a method and a system for determining a distance between toxic gas leakage and railway safety protection, and in the whole scheme, a more accurate and dynamic evaluation scheme is provided by comprehensively applying a railway facility vulnerability analysis method, an accident consequence method and a quantitative risk evaluation method. According to the method, physical and chemical characteristics, leakage conditions and meteorological conditions of toxic gas are considered, and vulnerability analysis is introduced, so that the safety of railway workers and passengers can be effectively protected in a toxic gas leakage event; meanwhile, the invention also aims to provide real-time data integration and processing capability so as to improve the accuracy and the real-time performance of evaluation and ensure that a reliable evaluation result and an emergency response plan can be quickly generated in an emergency. In this way, a scientific basis can be provided for the safety protection distance of railway facilities, and therefore the safety and reliability of railway transportation are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of railway safety protection, and in particular to a method and system for determining the distance between toxic gas leakage and railway safety protection. Background Art

[0002] In the early survey and design stage of railway projects, if there are hazardous chemical facilities adjacent to the line, the external safety protection distance is currently determined based on the "Code for Fire Protection of Building Design", "Code for Fire Protection of Railway Engineering Design", "Regulations on Railway Safety Management", "Petrochemical Combustible Gas and Toxic Gas Detection and Alarm Design Standards" and national or industry construction standards for related facilities. This type of distance usually only considers high-frequency, low-hazard fire scenarios. In reality, it is also necessary to consider the impact of accidents such as toxic gas leakage from related facilities on the railway. If the safety protection distances corresponding to the two different requirements are significantly different, it will lead to difficulties and delays in the progress of railway project construction. In serious cases, it will also affect the timely opening of the railway project or cause temporary additional major investments in the relocation of hazardous chemical enterprise facilities, resulting in a very passive situation in the survey and design work.

[0003] With the rapid development of industrialization, the production and transportation of hazardous chemicals are increasing, including highly toxic gases. These toxic gases may leak during storage, transportation or use, posing a serious threat to the surrounding environment and public safety. As an important land transportation mode, the facilities and operation safety along the railway may be directly affected by nearby toxic gas leakage incidents. At present, domestic and foreign research on the safety protection distance between hazardous chemical facilities and railways mainly focuses on fire and explosion scenarios, while there are relatively few systematic studies on toxic gas leakage scenarios. Existing studies are mostly based on empirical data and simplified models, lacking in-depth analysis of the specific vulnerabilities of railway facilities and the characteristics of toxic gas leakage. In addition, most of the current safety distance specifications do not fully consider the degree of harm that different hazardous chemical facilities may bring, and cannot provide targeted protection measures to ensure the comprehensive safety of railway facilities.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a method and system for determining the distance between toxic gas leakage and railway safety protection, which fully considers the specific vulnerability of railway facilities and the dynamic characteristics of toxic gas leakage, and can accurately and dynamically determine the railway safety protection distance.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for determining the distance between toxic gas leakage and railway safety protection, comprising:

[0008] Step 1: Collect railway facility data, toxic gas facility data and real-time meteorological data;

[0009] Step 2: Conduct vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility;

[0010] Step 3: Apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance;

[0011] Step 4: Use the quantitative risk assessment method to evaluate the risk level under different leakage accidents and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance;

[0012] Step 5: Combining the results of Step 2, Step 3 and Step 4, fit the railway safety protection distance calculation equation, and then determine the railway safety protection distance in combination with the toxic gas storage volume.

[0013] A system for determining the distance between toxic gas leakage and railway safety protection, comprising:

[0014] Data collection unit, used to collect railway facility data, toxic gas data and real-time meteorological data;

[0015] Vulnerability analysis unit, used to perform vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility;

[0016] The accident consequence method execution unit is used to apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance;

[0017] The quantitative risk assessment unit is used to evaluate the risk level under different leakage accidents through the quantitative risk assessment method and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance;

[0018] The comprehensive assessment model is used to integrate the results obtained by the vulnerability analysis unit, the accident consequence method execution unit and the quantitative risk assessment unit, fit the railway safety protection distance calculation equation, and then determine the railway safety protection distance in combination with the toxic gas storage volume.

[0019] A processing device, comprising: one or more processors; a memory for storing one or more programs;

[0020] When the one or more programs are executed by the one or more processors, the one or more processors implement the aforementioned method.

[0021] A readable storage medium stores a computer program, which implements the above method when the computer program is executed by a processor.

[0022] It can be seen from the technical solution provided by the present invention that a more accurate and dynamic assessment solution is provided by comprehensively using railway facility vulnerability analysis, accident consequence method and quantitative risk assessment method, which not only takes into account the physical and chemical properties, leakage conditions and meteorological conditions of toxic gases, but also introduces vulnerability analysis to ensure that in the event of toxic gas leakage, the safety of railway staff and passengers can be effectively protected; at the same time, the present invention also aims to provide real-time data integration and processing capabilities to improve the accuracy and real-time nature of the assessment, and ensure that reliable assessment results and emergency response plans can be quickly generated in emergency situations. In this way, a scientific basis can be provided for the safety protection distance of railway facilities, thereby improving the safety and reliability of railway transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0024] Figure 1 A flow chart of a method for determining the distance between toxic gas leakage and railway safety protection provided by an embodiment of the present invention;

[0025] Figure 2 A flowchart of a quantitative risk assessment method provided by an embodiment of the present invention;

[0026] Figure 3 A flow chart of a method for determining a safe distance for railway facilities provided in an embodiment of the present invention;

[0027] Figure 4 The toxic diffusion level distance of liquid ammonia leakage during the maximum credible accident simulation provided by the embodiment of the present invention;

[0028] Figure 5 The toxic diffusion level distance of liquid chlorine leakage during the maximum credible accident simulation provided by the embodiment of the present invention;

[0029] Figure 6 The toxic diffusion result of liquid ammonia leakage during the maximum credible accident simulation provided by the embodiment of the present invention;

[0030] Figure 7 The toxic diffusion result of liquid chlorine leakage during the maximum credible accident simulation provided by an embodiment of the present invention;

[0031] Figure 8The toxic diffusion level distance of liquid chlorine leakage during the extreme accident scenario simulation provided by the embodiment of the present invention;

[0032] Fig. 9 The toxic diffusion level distance of liquid ammonia leakage during the extreme accident scenario simulation provided by the embodiment of the present invention;

[0033] Fig.10 The toxic diffusion result of liquid ammonia leakage during the extreme accident scenario simulation provided by the embodiment of the present invention;

[0034] Fig.11 The toxic diffusion result of liquid chlorine leakage during the extreme accident scenario simulation provided by the embodiment of the present invention;

[0035] Fig.12 The fitting results of different scenarios of liquid chlorine provided by the embodiment of the present invention;

[0036] Fig.13 The fitting results of different scenarios of liquid chlorine provided by the embodiment of the present invention;

[0037] Fig.14 A schematic diagram of a system for determining the distance between toxic gas leakage and railway safety protection provided by an embodiment of the present invention;

[0038] Fig.15 A schematic diagram of a processing device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0040] First, the terms that may be used in this article are explained as follows:

[0041] The terms "include", "comprises", "contains", "has" or other descriptions with similar semantics should be interpreted as non-exclusive inclusion. For example, including certain technical feature elements (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or products, etc.) should be interpreted as including not only certain technical feature elements explicitly listed, but also other technical feature elements known in the art that are not explicitly listed.

[0042] The term "consisting of..." means excluding any technical feature elements not explicitly listed. If this term is used in a claim, it will make the claim closed, so that it does not contain technical feature elements other than the technical feature elements explicitly listed, except for the conventional impurities related to them. If this term only appears in a clause of a claim, it only limits the elements explicitly listed in the clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0043] The following is a detailed description of a scheme for determining the distance between toxic gas leakage and railway safety protection provided by the present invention. The contents not described in detail in the embodiments of the present invention belong to the prior art known to professionals in the field. If no specific conditions are specified in the embodiments of the present invention, the conditions are carried out according to the conventional conditions in the field or the conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used in the embodiments of the present invention, they are all conventional products that can be purchased commercially.

[0044] Embodiment 1

[0045] In order to address the deficiencies in the prior art in assessing the distance of impact of toxic gas leakage on railway facilities. Specifically, existing methods often rely on simplified models and empirical data, and fail to fully consider the specific vulnerabilities of railway facilities, personnel safety risks, and the dynamic characteristics of leakage events. In addition, existing models may have problems of low computational efficiency and insufficient real-time performance when dealing with large-scale or complex scenarios, and their feasibility and accuracy in practical applications need to be improved. Therefore, an embodiment of the present invention provides a method for determining the distance between toxic gas leakage and railway safety protection, such as Figure 1 As shown, it mainly includes the following steps:

[0046] Step 1: Collect railway facility data, toxic gas data and real-time meteorological data.

[0047] In an embodiment of the present invention, the collected railway facility data may include: structural characteristics, material type, usage status and surrounding environment, etc.; toxic gas data may include the physical and chemical properties of toxic gases, such as toxicity, density, volatility, etc.; real-time meteorological data may include wind speed, wind direction, atmospheric stability, etc.

[0048] Step 2: Conduct vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility.

[0049] In an embodiment of the present invention, from the perspective of personnel safety, the structural characteristics of railway facilities and the risks of railway facilities when toxic gases leak are analyzed, and the risk points affected by toxic gas leakage are identified; and the railway operation schedule and passenger flow are combined to determine the personnel exposure risks in different time periods; on this basis, the toxic exposure of personnel can be analyzed to determine the basic toxicity threshold of railway facilities.

[0050] Step 3: Apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance.

[0051] In an embodiment of the present invention, the most serious toxic gas leakage accident scenario is determined; an accident consequence model is used to combine the chemical properties of the toxic gas with real-time meteorological data to determine the impact range and toxic gas concentration, and thereby determine the corresponding safety distance.

[0052] Step 4: Use the quantitative risk assessment method to evaluate the risk level under different leakage accidents and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance.

[0053] In the embodiment of the present invention, for each leakage accident, the probability of occurrence and the consequences of the accident are analyzed, and the risk level under each leakage scenario is determined through quantitative risk calculation, and compared with the set risk benchmark to determine the corresponding safety distance. Specifically: historical data and accident statistics on toxic gas leakage can be collected to evaluate the probability of leakage accidents, and the consequences of leakage accidents can be simulated by CASST-QRA software, and then the risk level (including personal risk and social risk) under different leakage accidents can be evaluated by performing quantitative risk assessment, and the corresponding safety distance can be determined in combination with the set risk benchmark.

[0054] In the embodiment of the present invention, the first and second are mainly used as identifiers, indicating that steps 3 and 4 calculate two types of safety distances. Of course, the first and second can be swapped as needed, that is, the safety distance obtained in step 3 is called the second type of safety distance, and the safety distance obtained in step 4 is called the first type of safety distance. Such a swap does not affect the overall understanding of the solution.

[0055] Step 5: Based on the basic toxicity threshold, the first-category safety distance, and the second-category safety distance corresponding to each railway facility, a calculation equation for the railway safety protection distance is fitted, and then the railway safety protection distance is determined based on the storage volume of toxic gases.

[0056] In the embodiment of the present invention, the results of vulnerability analysis, accident consequence method and quantitative risk assessment method are integrated together, so that not only the safety protection distance of railway facilities can be obtained, but also the emergency evacuation area and necessary protection measures can be determined.

[0057] The above scheme provided by the embodiment of the present invention provides a more accurate and dynamic evaluation method by comprehensively using railway facility vulnerability analysis, accident consequence method and quantitative risk assessment method. This method not only takes into account the physical and chemical properties, leakage conditions and meteorological conditions of toxic gases, but also places special emphasis on vulnerability analysis from the perspective of personnel safety to ensure that the safety of railway staff and passengers can be effectively protected in the event of a toxic gas leakage. At the same time, the present invention also aims to provide real-time data integration and processing capabilities to improve the accuracy and real-time nature of the evaluation, and ensure that reliable evaluation results and emergency response plans can be quickly generated in emergency situations. Through this method, a scientific basis can be provided for the safety protection distance of railway facilities, thereby improving the safety and reliability of railway transportation.

[0058] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the method provided by the embodiment of the present invention is described in detail with reference to specific embodiments below.

[0059] 1. Conduct a vulnerability analysis of railway facilities, identify key risk points, crowded areas, and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility.

[0060] This section focuses on assessing the vulnerability of railway facilities, especially from the perspective of personnel safety, including the potential exposure risks of railway staff and passengers. Analyze the structural characteristics of railway facilities and the potential risks of these railway facilities in the event of toxic gas leaks. Consider the railway operating schedule and passenger flow to determine the exposure risks of personnel in different time periods.

[0061] Specifically: First, it is necessary to identify and evaluate key risk points that may be affected by toxic gas leaks, including basic railway facilities such as railway lines, stations, signal systems, bridges and tunnels, as well as crowded areas that may be affected in the event of a leak, such as waiting rooms, platforms and staff areas. Through a detailed analysis of the structural characteristics, material types, usage conditions and surrounding environment of railway facilities, potential weak links and sensitive areas can be identified. In addition, the railway operation schedule and passenger flow must be considered to assess the risk of personnel exposure in different time periods. Through this analysis, the toxic exposure of personnel on the railway can be further analyzed, and then the basic toxicity threshold of railway facilities can be determined, thereby providing basic data and key parameters for subsequent accident consequence simulation and risk assessment, ensuring the accuracy and practicality of the assessment results.

[0062] Table 1 provides examples of toxic gas exposure thresholds for construction workers at various railway facilities. The thresholds are used to determine the range or path of toxic spread. The following thresholds refer to the emergency response planning guidelines currently developed by the American Industrial Hygiene Association (AIHA).

[0063] Table 1: Toxic gas exposure thresholds for construction workers at various railway facilities

[0064]

[0065]

[0066] 2. Apply the accident consequence method to simulate the most serious leakage scenario, calculate the impact range and toxic gas concentration, and thereby determine the corresponding safety distance (called the first type of safety distance).

[0067] In the embodiment of the present invention, the accident consequence method is applied, combined with the Gaussian puff model and CASST-QRA software, to simulate the diffusion of toxic gases under the most serious leakage scenario, and calculate the impact range and toxic gas concentration under different leakage conditions. Specifically: determine the most serious toxic gas leakage accident scenario, including: toxic gas reserves, leakage aperture, leakage rate, leakage duration and possible leakage path and other conditions, use accident consequence models, such as Gaussian puff model or plume model, etc., to calculate the diffusion range and impact of toxic gas leakage, and determine the corresponding safety distance based on the calculation results to ensure personnel safety in the worst case.

[0068] 3. Implement quantitative risk assessment method to evaluate the risk level under different leakage scenarios and determine the corresponding safety distance (called the second type of safety distance).

[0069] Risk (probability of death times / year * person) = possibility of accident (probability of occurrence per year / year) × consequence of accident (probability of causing casualties times / person). This formula can assess the risk of hazardous chemical storage facilities to determine the risk level of a leakage scenario.

[0070] The quantitative risk assessment method is a method of quantitatively analyzing and calculating the frequency and consequences of accidents in hazardous chemical production and storage facilities, and determining the safety distance based on acceptable risk standards. Combining the results of the above two parts, a calculation formula for railway safety protection distance can be fitted, such as Figure 2 As shown, the relevant process steps are as follows:

[0071] a) Collect information and data;

[0072] b) determine the evaluation unit;

[0073] c) Hazard identification and leakage scenario recognition;

[0074] d) Analyze the probability of accidents;

[0075] e) Analyze the consequences of the accident;

[0076] f) quantitative risk calculation;

[0077] g) Determine the second type of safety distance.

[0078] In the embodiment of the present invention, the quantitative risk assessment method is a method for quantitatively analyzing and calculating the frequency and consequences of hazardous chemical leakage accidents. In the present invention, for each leakage scenario, historical data and accident statistics on toxic gas leakage will be collected to assess the probability of leakage accidents. At the same time, the scope of leakage accidents is simulated in combination with CASST-QRA software, the consequences of accidents are analyzed, and the personal risk (PAR) and social risk (SAR) under each leakage scenario are calculated, which includes analyzing the casualties, property losses and environmental impacts that may be caused by leakage accidents. Through quantitative risk calculation, the risk level under different leakage scenarios can be determined and compared with the acceptable risk standard (risk benchmark) to determine the corresponding safe distance of railway facilities.

[0079] The safety protection distance guarantees the intrinsic safety of the most common and serious accidents, and the emergency distance guarantees the safety of railway facilities in extreme scenarios. It also provides emergency measures for safety response, including temporary parking, personnel evacuation, line closure, etc., to avoid hazardous accidents that threaten the safety of railway facilities and personnel. The following uses the two scenarios of maximum credible accidents and extreme accidents as examples to introduce the method and process for determining the second type of safety distance in these two scenarios. Figure 3 As shown, Figure 3 The safety protection distance and emergency response distance in the figure are the second-class safety distances corresponding to these two scenarios.

[0080] The leakage diffusion calculation scheme involved in the calculation process of the second and third parts above is introduced as follows.

[0081] Atmospheric stability is usually determined by the Pasquill classification method. Atmospheric stability is divided into six categories: A, B, C, D, E and F. The specific classification of atmospheric stability is shown in Tables 2 and 3.

[0082] Table 2: Pasquill atmospheric stability determination

[0083]

[0084] Table 3: Determination of sunlight intensity

[0085]

[0086]

[0087] Calculate the toxic gas concentration using the Pasquill-Gifford model:

[0088] (1) Calculate the H r The concentration of toxic gases in a plume from a continuous steady-state source at a given location (x, y, z) is calculated as follows:

[0089]

[0090] in, <c>(x,y,z) is the concentration of toxic gas at a given location (x,y,z) after a stable flow field is formed during continuous emission, in kilograms per cubic meter (kg / m 3 ); x is the downwind distance, y is the crosswind distance, z is the vertical wind direction, all in meters (m); Q is the mass flow rate of continuously discharged materials, in kilograms per second (kg / s); π is pi, u is the wind speed, in meters per second (m / s); σ y With σ z are the diffusion coefficients in the crosswind and vertical wind directions.

[0091] (2) Calculate the H r For a smoke puff at a high altitude, the coordinate system on the ground moves with the smoke puff, and the center of the coordinate system is located at the center of the smoke puff. The average concentration equation of the smoke puff center at x=ut is calculated as follows:

[0092]

[0093] in, <c>(x, y, z, t) is the average concentration of toxic gas at a given location (x, y, z) and time t during instantaneous emission, Q * is the mass of material discharged instantaneously, in kilograms (kg); σ x is the diffusion coefficient in the downwind direction.

[0094] The Pasquill-Gifford model diffusion coefficient is determined using the method in Tables 4 and 5.

[0095] Table 4: Diffusion coefficient equation of the Pasquill-Gifford model for plume diffusion (downwind distance x in meters)

[0096]

[0097]

[0098] Table 5: Pasquill-Gifford model diffusion coefficient equation for smoke puff diffusion (downwind distance x in meters)

[0099]

[0100] The following is for Figure 3 The maximum credible accident and extreme accident scenarios shown are simulated and illustrated.

[0101] 1. Maximum credible accident simulation.

[0102] Simulation conditions: Tank size 50m 3 、90m 3 、120m 3 、200m 3 、400m 3 ; Storage temperature: 20℃; Pressure: 0.6Mpa for liquid chlorine, 1.1Mpa for liquid ammonia; Weather conditions: Wind speed 1.5m / s; Atmospheric stability F; Leakage size: 50mm aperture. The influence of safe distance on the toxic downwind diffusion concentration after leakage of 50mm aperture in different flammable liquid storage tanks is analyzed. The simulation results are shown in Table 6-7.

[0103] Table 6: Diffusion level of toxic gas leaking from different tanks with a pore size of 50 mm

[0104]

[0105] Table 7: Impact of toxic gas load on safety distance of 50mm aperture leakage in different tanks

[0106]

[0107]

[0108] The diffusion impact distance under different reserve conditions, such as Figure 4 to Figure 7 As shown, Figure 4 The toxic diffusion level distance of 50mm for liquid ammonia leakage is: Figure 5 The toxic diffusion level distance of 50mm for liquid chlorine leakage is: Figure 6 The toxic diffusion result of liquid ammonia leakage 50mm, Figure 7 This is the toxic diffusion result of a 50mm liquid chlorine leak.

[0109] The above simulation results show that: under the same conditions, the diffusion concentration of toxic gases affects the distance slightly with the storage capacity of the storage tank, different gases have a greater impact on the safe distance of 50mm aperture leakage, different substances have a more obvious change in the distance affected by downwind, and the diffusion difference is large.

[0110] 2. Simulation of extreme accident scenarios.

[0111] Simulation conditions: Tank size 50m 3 、90m 3 、120m 3 、200m 3 、400m 3 、650m 3 , 1000m 3 , 2000m 3 、3000m 3 ; Storage temperature: 20; Pressure: 0.6Mpa for liquid chlorine, 1.1Mpa for liquid ammonia; Weather conditions: Wind speed 1.5m / s; Atmospheric stability F; Leakage size: 50mm aperture. The influence of safe distance on the toxic downwind diffusion concentration after leakage of 50mm aperture in different flammable liquid storage tanks is analyzed. The simulation results are shown in Table 8-9.

[0112] Table 8: Safe distances for diffusion of toxic gases from complete leakage of different storage tanks

[0113]

[0114] Table 9: Safe distances for toxic loads of toxic gases from completely leaking different tanks

[0115]

[0116] The diffusion impact distance under different reserve conditions, such as Figure 8 to Figure 11 shown. Figure 8 The toxic diffusion level distance of liquid chlorine leakage is: Fig. 9 is the toxic diffusion level distance of liquid ammonia leakage, Fig.10 It is the result of the toxic diffusion of liquid ammonia leakage. Fig.11 It is the result of toxic diffusion caused by liquid chlorine leakage.

[0117] The above simulation results show that: under the same conditions, the diffusion concentration level ERPG-1 of toxic gas has the longest impact distance, and the concentration impact distance varies greatly with the storage capacity of the tank. Different toxic gases have different effects on the safe distance of leakage. The main reason is that toxic gases are highly volatile. Under the same environment, the diffusion of different substances changes significantly with the downwind impact distance, and the diffusion range varies greatly.

[0118] 4. Use a comprehensive assessment model to determine railway safety protection distances.

[0119] In an embodiment of the present invention, a comprehensive assessment model is developed to integrate the results of vulnerability analysis, accident consequence method and quantitative risk assessment method to determine the final safety protection distance. The model takes into account the characteristics of various toxic gases, such as toxicity, density, volatility, etc., as well as the impact of meteorological conditions on gas diffusion. The model ultimately outputs the railway safety protection distance, and also outputs the corresponding emergency evacuation area and necessary protective measures. In the specific application process, the model can also provide a set of detailed safety protection distance charts, including safety distances under different toxic gases and different leakage conditions. Through this model, railway safety managers can easily input parameters, run simulations, and view results, thereby providing a scientific basis for the safety protection and emergency response of railway facilities.

[0120] In general, after calculations in the above three parts, the first type of safety distance can be compared with the second type of safety distance to obtain the basic toxic threshold impact distance range of the corresponding railway facilities, thereby drawing an impact range map to determine the corresponding safety distance, and taking the toxic gas reserves as a variable to determine the safety distance corresponding to different toxic gas reserves, and thereby fitting the railway safety protection distance calculation equation, after which the toxic gas storage amount can be brought in to determine the railway safety protection distance; wherein the toxic gas reserves are parameters included when simulating the most serious toxic gas leakage accident scenario and evaluating the risk levels under different leakage accidents.

[0121] In practical applications, different railway safety protection distance calculation equations can be fitted according to different leakage scenarios. For example, corresponding railway safety protection distance calculation equations can be fitted for continuous leakage and instantaneous leakage respectively.

[0122] Taking liquid ammonia and liquid chlorine as examples, the simulation results of liquid ammonia and liquid chlorine were fitted and compared according to the toxicity measurement level to obtain the influence of the storage tank on their diffusion distance. The fitting results are as follows: Figure 12-13 As shown, Fig.12 The fitting results of different scenarios of liquid chlorine are: Fig.13 are the fitting results of different scenarios of liquid ammonia. The y in the figure is the fitting formula result (i.e., the railway safety protection distance calculation equation), x is the input in the formula (i.e., the toxic gas reserves), R 2 is the determination coefficient, the closer to 1 the better.

[0123] The fitting results are explained below.

[0124] (1) Analysis of the safe distance for continuous leakage of liquid ammonia with a leakage hole diameter of 50 mm. Before reaching the maximum value of 400 cubic meters, the safe distance of the following storage tanks is calculated according to the following formula:

[0125] Ds=217.51ln(V1)-308.36

[0126] Among them, V1 is the storage capacity of the liquid ammonia tank, unit: cubic meter; Ds is the safety protection distance of railway facilities, unit: meter.

[0127] The safety distance analysis of the continuous leakage of liquid chlorine with a leakage aperture of 50mm shows that the safety distance of the tank with a maximum value of more than 200 cubic meters is about 9400 meters, while the safety distance of the tank with a leakage aperture of less than 200 cubic meters is calculated according to the following formula:

[0128] Ds=2653.5ln(V2)-4282.5

[0129] Among them, V2 is the storage capacity of liquid chlorine storage tank, unit: cubic meter.

[0130] (2) The safety distance for instantaneous leakage of storage tank inventory is fitted. There is a positive correlation between the safety distance and the volume of the storage tank, and the effect of the storage tank inventory on toxic gas leakage is calculated.

[0131] Ds=73.402V1 0.3899

[0132] Ds=629.93V2 0.4617

[0133] Among them, V1 is the storage capacity of liquid ammonia storage tank, V2 is the storage capacity of liquid chlorine storage tank, and Ds is the safety protection distance of railway facilities.

[0134] In the above two sets of formulas, the numerical values ​​involved are coefficients obtained by fitting based on the scheme introduced above. The numerical values ​​are only illustrative in the above example scenarios and do not constitute a limitation. In practical applications, they can be adjusted according to actual conditions.

[0135] The above solution provided by the embodiment of the present invention mainly achieves the following beneficial effects:

[0136] 1. Promote land use and urban development planning: Understanding the optimal safety distance can avoid the construction of hazardous chemical facilities near densely populated areas. This technical solution helps to plan appropriate land use and urban development to ensure the sustainable development of the city and the safety of residents.

[0137] 2. Reduce economic losses: By reasonably determining the safety protection distance between hazardous chemical facilities and railway lines, this technical solution helps to avoid recurring or disruptive problems in the later stages of the project, reduce railway project delays or additional relocation investment caused by insufficient safety distance, and thus reduce economic losses.

[0138] 3. Improve the efficiency of railway project promotion: This technical solution establishes a set of rapid quantitative methods to guide the route selection of hazardous chemical facilities in railway survey and design, provide important technical support for the early route selection demonstration of railway survey and design, stabilize the railway line plan, and improve the efficiency of railway project promotion.

[0139] 4. Enhance the safety of railway operations: This technical solution helps to take more effective safety measures during the railway operation stage and enhance the overall safety of the railway system by analyzing the vulnerability of railway facilities in detail and identifying key risk points and crowded areas.

[0140] 5. Enhance emergency preparedness capabilities: This solution provides important technical support for the formulation of emergency preparedness plans and response strategies by simulating the changes in the storage capacity of various flammable and explosive hazardous chemicals storage facilities and the regular changes in the external safety protection distance of the railway, thereby enhancing the ability to respond to possible accidents or leaks.

[0141] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above embodiments can be implemented by software, or by means of software plus necessary general hardware platforms. Based on such understanding, the technical solutions of the above embodiments can be embodied in the form of software products, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0142] Embodiment 2

[0143] The present invention also provides a system for determining the distance between toxic gas leakage and railway safety protection, which is mainly used to implement the method provided in the above embodiment, such as Fig.14 As shown, the system mainly includes:

[0144] Data collection unit, used to collect railway facility data, toxic gas data and real-time meteorological data;

[0145] Vulnerability analysis unit, used to perform vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility;

[0146] The accident consequence method execution unit is used to apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance;

[0147] The quantitative risk assessment unit is used to evaluate the risk level under different leakage accidents through the quantitative risk assessment method and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance;

[0148] The comprehensive assessment model is used to integrate the results obtained by the vulnerability analysis unit, the accident consequence method execution unit and the quantitative risk assessment unit, fit the railway safety protection distance calculation equation, and then determine the railway safety protection distance in combination with the toxic gas storage volume.

[0149] Considering that the main technical details involved in the system have been introduced in detail in the previous embodiments, they will not be repeated here.

[0150] Technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the system can be divided into different functional modules to complete all or part of the functions described above.

[0151] Embodiment 3

[0152] The present invention also provides a processing device, such as Fig.15 As shown, it mainly includes: one or more processors; a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the methods provided in the aforementioned embodiments.

[0153] Furthermore, the processing device also includes at least one input device and at least one output device; in the processing device, the processor, memory, input device, and output device are connected via a bus.

[0154] In the embodiment of the present invention, the specific types of the memory, input device and output device are not limited; for example:

[0155] The input device may be a touch screen, an image acquisition device, a physical button or a mouse, etc.;

[0156] The output device may be a display terminal;

[0157] The memory may be a random access memory (RAM) or a non-volatile memory, such as a disk memory.

[0158] Embodiment 4

[0159] The present invention also provides a readable storage medium storing a computer program, which implements the method provided in the above embodiment when the computer program is executed by a processor.

[0160] In the embodiment of the present invention, the readable storage medium is a computer-readable storage medium and can be set in the aforementioned processing device, for example, as a memory in the processing device. In addition, the readable storage medium can also be a U disk, a mobile hard disk, a read-only memory (ROM), a disk or an optical disk, etc., which can store program codes.

[0161] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.< / c> < / c>

Claims

1. A method for determining the distance between toxic gas leakage and railway safety protection, characterized in that: include: Step 1: Collect railway facility data, toxic gas data and real-time meteorological data; Step 2: Conduct vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility; Step 3: Apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance; Step 4: Use the quantitative risk assessment method to evaluate the risk level under different leakage accidents and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance; Step 5: Combining the results of Step 2, Step 3 and Step 4, fit the railway safety protection distance calculation equation, and then determine the railway safety protection distance in combination with the toxic gas storage volume.

2. A method for determining the distance between toxic gas leakage and railway safety protection according to claim 1, characterized in that: The vulnerability analysis of railway facility data, identification of risk points and personnel exposure risks, and calculation of the basic toxicity thresholds corresponding to each railway facility include: From the perspective of personnel safety, the structural characteristics of railway facilities and the risks of railway facilities in the event of toxic gas leakage are analyzed to identify risk points affected by toxic gas leakage. In addition, the railway operation schedule and passenger flow are combined to determine the personnel exposure risks in different time periods. Based on this, the toxic exposure of personnel is analyzed to determine the basic toxicity threshold of railway facilities.

3. The method for determining the distance between toxic gas leakage and railway safety protection according to claim 1, characterized in that: The accident consequence method is used to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance, including: Determine the most serious toxic gas leak accident scenario; use the accident consequence model, combine the chemical properties of toxic gases with real-time meteorological data to correspond to the impact range and toxic gas concentration, and thereby determine the corresponding safe distance.

4. A method for determining the distance between toxic gas leakage and railway safety protection according to claim 1 or 3, characterized in that: Also includes: Calculate toxic gas concentrations using the Pasquill-Gifford model, including: Calculate the ground H r The concentration of toxic gases in a plume from a continuous steady-state source at a given location (x, y, z) is calculated as follows: in, <c>(x, y, z) is the concentration of toxic gas at a given location (x, y, z) after a stable flow field is formed during continuous discharge. x is the downwind distance, y is the sidewind distance, and z is the vertical wind distance. Q is the mass flow rate of the continuously discharged material, π is the circumference, u is the wind speed, σ y With σ z is the diffusion coefficient in the crosswind and vertical wind directions;< / c> Calculate the ground H r For a smoke puff at a high altitude, the coordinate system on the ground moves with the smoke puff, and the center of the coordinate system is located at the center of the smoke puff. The average concentration equation of the smoke puff center at x=ut is calculated as follows: in, <c>(x, y, z, t) is the average concentration of toxic gas at a given location (x, y, z) and time t during instantaneous emission, Q * is the mass of material discharged instantaneously, σ x is the diffusion coefficient in the downwind direction.< / c> 5. The method for determining the distance between toxic gas leakage and railway safety protection according to claim 1 is characterized in that: The quantitative risk assessment method is used to evaluate the risk level under different leakage accidents and calculate the corresponding safety distance under different leakage accidents, including: For each leakage accident, the probability of occurrence and the consequences of the accident are analyzed, and the risk level under each leakage scenario is determined through quantitative risk calculation. It is then compared with the set risk benchmark to determine the corresponding safety distance.

6. A method for determining the distance between toxic gas leakage and railway safety protection according to claim 5, characterized in that: The analysis of the occurrence probability includes: collecting historical data and accident statistics about toxic gas leakage to evaluate the occurrence probability of leakage accidents.

7. The method for determining the distance between toxic gas leakage and railway safety protection according to claim 1, characterized in that: The results of step 2, step 3 and step 4 are integrated to fit the railway safety protection distance calculation equation, and then the railway safety protection distance is determined in combination with the toxic gas storage volume, including: After calculations in steps 2, 3, and 4, the first type of safety distance is compared with the second type of safety distance to obtain the basic toxicity threshold impact distance range of the corresponding railway facilities to determine the corresponding safety distance; the toxic gas reserves are used as variables to determine the safety distances corresponding to different toxic gas reserves, and the railway safety protection distance calculation equation is fitted accordingly, and then the toxic gas storage amount is brought in to determine the railway safety protection distance; wherein the toxic gas reserves are parameters included when simulating the most serious toxic gas leakage accident scenario and evaluating the risk levels under different leakage accidents.

8. A system for determining the distance between toxic gas leakage and railway safety protection, characterized in that: include: Data collection unit, used to collect railway facility data, toxic gas data and real-time meteorological data; Vulnerability analysis unit, used to perform vulnerability analysis on railway facility data, identify risk points and personnel exposure risks, and calculate the basic toxicity threshold corresponding to each railway facility; The accident consequence method execution unit is used to apply the accident consequence method to simulate the most serious toxic gas leakage accident scenario and determine the corresponding safety distance, which is called the first type of safety distance; The quantitative risk assessment unit is used to evaluate the risk level under different leakage accidents through the quantitative risk assessment method and calculate the corresponding safety distance under different leakage accidents, which is called the second type of safety distance; The comprehensive assessment model is used to integrate the results obtained by the vulnerability analysis unit, the accident consequence method execution unit and the quantitative risk assessment unit, fit the railway safety protection distance calculation equation, and then determine the railway safety protection distance in combination with the toxic gas storage volume.

9. A processing device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of claims 1 to 7.

10. A readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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