Substance self-accelerated decomposition temperature detection method and system

Abstract

The invention discloses a substance self-accelerated decomposition temperature detection method and system, and belongs to the technical field of self-accelerated decomposition temperature detection.The method specifically comprises the steps that a to-be-detected substance is taken to be subjected to C80 calorimetric experiments at different temperature rise rates, heat flow-time / heat flow-temperature data are obtained, a base line is constructed according to the heat flow-time data, and the self-accelerated decomposition temperature of the to-be-detected substance is obtained based on the constructed base line; calculating the reaction conversion rate and conversion rate of a substance, selecting a conversion rate calculation interval and a conversion rate interval to screen the time and temperature of experimental data, carrying out minimization calculation by utilizing the processed time and temperature data under a specified conversion rate level, solving the activation energy, analyzing the change relation of the activation energy along with the reaction conversion rate of the substance, and calculating the activation energy according to the change relation. Carrying out isothermal process prediction according to the prediction equation, simulating a heat release process, calculating a heat release-time relation of the substance under an isothermal condition according to heat release characteristics, determining a packaging specification and a material of the substance to be detected, and carrying out modeling; and the risk in the detection process is greatly reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of self-accelerating decomposition temperature detection, and in particular relates to a method and system for detecting the self-accelerating decomposition temperature of a substance. Background Art

[0002] Self-accelerating decomposition temperature (SADT) is a crucial parameter in the storage, transportation and use management of chemical substances. Self-accelerating decomposition temperature refers to the lowest ambient temperature at which the reactive chemical substances in a specified package undergo self-accelerating decomposition within 7 days. It is closely related to the exothermic characteristics of the reactive chemical substances in the package, the materials and specifications of the packaging. Once a chemical substance undergoes self-accelerating decomposition, a large amount of heat will be released, which may cause serious thermal explosion accidents, resulting in casualties and property losses. Traditional detection methods usually require the use of a large number of samples for long-term high-temperature heating, which not only has a high risk, but also has a long measurement time and high cost. Therefore, it is of great practical significance to develop a safe, efficient and low-cost method for detecting the self-accelerating decomposition temperature of substances.

[0003] For example, the Chinese patent with publication number CN113740372A discloses a method for quickly calculating the self-accelerating decomposition temperature of a substance and its use, which belongs to the technical field of studying the rapid determination of the thermal hazard characteristics of a substance. It solves the technical problems of long self-accelerating decomposition temperature test cycle and high danger caused by large test sample quantity. The method includes: testing the decomposition reaction and heat release characteristics of the substance in the air to obtain the heat flow rate curve of the substance; secondly, observing whether the heat flow rate curve has an exothermic peak within room temperature to 300°C. If an exothermic peak occurs, the thermal stability parameter of the substance is calculated, and the thermodynamic parameters of the substance are calculated; according to the thermodynamic parameters, the relationship between the temperature and the reaction heat release rate is made, and according to the packaging parameters corresponding to the substance, the relationship between the temperature and the heat flow rate removed by the cooling system is made; finally, when qe is tangent to qr, the ambient temperature corresponding to qe is the SADT of the substance. The inventive method can quickly and effectively obtain the self-accelerating decomposition temperature of the substance, and has high safety.

[0004] The defects of the above patent are: it adopts a relatively simple situation in the thermal equilibrium relationship of the material-packaging system, and has a high adaptability only to liquid and gas samples, and the solution accuracy and solution adaptability are limited. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a method and system for detecting the self-accelerating decomposition temperature of a substance. In order to solve the problems of high risk, low efficiency and high cost in the prior art, by solving the activation energy and predicting the time, simulation calculation is adopted to quickly and effectively obtain the self-accelerating decomposition temperature of the substance with high safety.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for detecting the self-accelerating decomposition temperature of a substance comprises the following specific steps:

[0008] Step S1: taking the material to be tested and performing a C80 calorimetric experiment at different temperature rise rates to obtain heat flow-time / heat flow-temperature data;

[0009] Step S2: constructing a baseline according to the heat flow-time data, calculating the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and selecting the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data;

[0010] Step S3: using the processed time and temperature data at the specified conversion rate level, perform minimization calculations to solve the activation energy and analyze the relationship between the activation energy and the substance reaction conversion rate;

[0011] Step S4: performing isothermal process prediction according to the prediction equation to simulate the exothermic process;

[0012] Step S5: Calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics;

[0013] Step S6: Determine the packaging specifications and materials of the substance to be tested, and perform modeling;

[0014] Step S7: Obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

[0015] Specifically, the specific steps of step S2 are:

[0016] Step S201: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is:

[0017]

[0018] Among them, α(t) represents the reaction conversion rate of the substance at time t, S(t) represents the heat flow signal at time t, W(t) represents the baseline at time t, t0 represents the initial time of the reaction, t represents any time after the start of the reaction, and t end Indicates the end time of the reaction;

[0019] Step S202: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is:

[0020]

[0021] Among them, α represents the reaction conversion rate of the substance, Indicates the reaction conversion rate of a substance;

[0022] Step S203: Filter the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval, select the conversion rate range as 0-1, the conversion rate interval Δα=0.05, and filter out the temperature and time data corresponding to the conversion rate α=0, 0.05, 0.1, 0.15, 0.2, ..., 0.85, 0.9, 0.95, 1 in each group of experimental data.

[0023] Specifically, the specific steps of step S3 are:

[0024] Step S301: Based on the processed time and temperature data at the specified conversion rate level, a solution formula for the reaction activation energy of the substance is constructed. The specific formula is:

[0025]

[0026] Among them, φ(E α ) represents the formula for solving the activation energy of the reaction of a substance, E α represents the reaction activation energy of the substance, i and j represent the data under different temperature control programs, n represents the number of experimental data groups, J[] represents the temperature integral term, T(t α ) represents the reaction temperature at time t when the conversion rate is α, t α represents the time point corresponding to the conversion rate α, R represents the gas constant, exp() represents the exponential function, and T(t) represents the reaction temperature at time t;

[0027] Step S302: using the Simpson integral solution formula to solve the temperature integral term, the specific formula is:

[0028]

[0029] When the selected conversion rate interval Δα is small enough, it is determined that the reaction activation energy of the substance does not change within the short conversion rate change interval;

[0030] Substitute the solution of the temperature integral term into the solution formula of the reaction activation energy of the substance, and obtain the reaction activation energy E of the substance by minimizing the solution formula of the reaction activation energy of the substance. α .

[0031] Specifically, the specific steps of step S4 are:

[0032] Step S401: According to thermodynamics and isoconversion theory, under the same conversion rate condition, the temperature integrals of different temperature control programs are equal. The temperature integral term J[] is extended to any temperature program. The specific formula is:

[0033]

[0034] in, The reaction time is The corresponding reaction temperature;

[0035] Step S402: construct a reaction time prediction equation, the specific formula is:

[0036]

[0037] Among them, t α represents the reaction time prediction equation, i.e., the predicted reaction time at the conversion rate α, p and q represent the temperature control program of different experiments and the predicted temperature control program, respectively.

[0038] Specifically, the specific formula of the heat release-time relationship of the substance under isothermal conditions in step S5 is:

[0039]

[0040] Among them, Q(t * ) represents the heat release-time relationship of a substance under isothermal conditions, that is, under isothermal conditions, t * The heat released at the time, Q0 represents the specific heat released by the substance in the experiment, represents the predicted reaction rate under isothermal conditions.

[0041] A material self-accelerating decomposition temperature detection system, used to implement a material self-accelerating decomposition temperature detection method, comprising: a data acquisition module, a screening module, an activation energy analysis module, a prediction module, a relationship analysis module, a packaging modeling module and a simulation solution module;

[0042] The data acquisition module is used to perform C80 calorimetric experiments on the substance to be tested at different temperature rise rates to obtain heat flow-time / heat flow-temperature data;

[0043] The screening module is used to construct a baseline according to the heat flow-time data, calculate the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and select the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data;

[0044] The activation energy analysis module is used to use the processed time and temperature data at the specified conversion rate level to perform minimization calculations, solve the activation energy, and analyze the relationship between the activation energy and the substance reaction conversion rate;

[0045] The prediction module is used to perform isothermal process prediction according to the prediction equation and simulate the exothermic process;

[0046] The relationship analysis module is used to calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics;

[0047] The packaging modeling module is used to determine the packaging specifications and materials of the substance to be tested and to perform modeling;

[0048] The simulation solution module is used to obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

[0049] Specifically, the screening module includes: a calculation unit and a screening unit;

[0050] The calculation unit is used to calculate the reaction conversion rate and reaction conversion rate of the substance based on the constructed baseline;

[0051] The screening unit is used to screen the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval.

[0052] Specifically, the activation energy analysis module includes: a formula solving unit, a temperature integral solving unit and an activation energy solving unit;

[0053] The formula solving unit is used to construct a formula for solving the reaction activation energy of the substance based on the time and temperature data at the specified conversion rate level after processing;

[0054] The temperature integral solving unit is used to solve the temperature integral term by using the Simpson integral solving formula;

[0055] The activation energy solving unit is used to solve the reaction activation energy of the substance by minimizing the reaction activation energy solving formula of the substance.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] 1. The present invention proposes a method for detecting the self-accelerating decomposition temperature of a substance. Unlike conventional detection which requires real packaging and a large sample mass and is heated in a high-temperature environment for a long time, the present invention adopts simulation calculation, which greatly reduces the risk in the detection process and has high safety.

[0058] 2. The present invention proposes a method for detecting the self-accelerating decomposition temperature of a substance, which is a thermal simulation solution method based on trace (several hundred milligrams) experiments, which significantly shortens the solution time of SADT and greatly saves costs. The traditional measurement method requires multiple groups of heating experiments for a long time, has a long measurement time and has high requirements on the detection instrument and sample quality, which increases the experimental cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A flow chart of a method for detecting the self-accelerating decomposition temperature of a substance provided by the present invention;

[0060] Figure 2 The multi-rate calorimetric heat flow-temperature / time image diagram provided by the present invention;

[0061] Figure 3 The conversion rate-temperature curve provided by the present invention;

[0062] Figure 4 The conversion rate-time curve diagram provided by the present invention;

[0063] Figure 5 This is an architecture diagram of a material self-accelerating decomposition temperature detection system provided by the present invention. DETAILED DESCRIPTION

[0064] The present application is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements can also be made without departing from the concept of the present application. These all belong to the protection scope of the present application.

[0065] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0066] It should be noted that, if there is no conflict, the various features in the embodiments of the present application can be combined with each other, all within the scope of protection of the present application. In addition, although the functional module division is performed in the device schematic diagram and the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in a sequence different from the module division in the device or the flow chart. In addition, the words "first", "second", "third" and the like used in the present application do not limit the data and the execution order, but only distinguish the same items or similar items with substantially the same functions and effects.

[0067] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0068] Example 1

[0069] See also Figure 1-4 The present invention provides an embodiment: a method for detecting the self-accelerating decomposition temperature of a substance, comprising the following specific steps:

[0070] Step S1: Take a small amount of the substance to be tested and perform multiple groups of C80 calorimetric experiments at different temperature rise rates to obtain multiple groups of heat flow-time / heat flow-temperature data. Usually, the experimental heat flow-time data of reactive chemical substances is composed of one or more heat flow peaks, see Figure 2 , if no exothermic decomposition peak appears in the experimental temperature range, the SADT solution is not performed;

[0071] The C80 calorimetric experiment used a C80 calorimeter, developed by the French company Setram, which uses 3D-Cavlet calorimetry;

[0072] Step S2: constructing a baseline according to the heat flow-time data, calculating the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and selecting the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data;

[0073] The specific steps of step S2 are:

[0074] Step S201: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is:

[0075]

[0076] Where α(t) represents the reaction conversion rate of the substance at time t, S(t) represents the heat flow signal at time t, W(t) represents the baseline at time t, t0 represents the initial time of the reaction, which is generally the time when the heat flow begins to deviate from the baseline, t represents any time after the start of the reaction, and t end Indicates the end time of the reaction, generally the time when the heat flow returns to the baseline;

[0077] In this embodiment, Describes the accumulation of the difference between the actual heat generated by the substance and the baseline heat from the start of the reaction to time t, that is, the actual heat released during the reaction. The total heat release during the entire reaction process is obtained by performing the above processing on multiple groups (at least five groups of data) of experimental data to obtain five groups of conversion rate-temperature / conversion rate-time data (curves) with different experimental temperature rise rates. Figure 3 (Conversion rate-temperature curve) and Figure 4 (Conversion rate-time curve), through the ratio of the two, we can get the conversion rate of the reaction at time t, that is, the proportion of the reacted part to the total reaction amount, so that we can intuitively understand the degree of reaction;

[0078] Step S202: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is:

[0079]

[0080] Among them, α represents the reaction conversion rate of the substance, Indicates the reaction conversion rate of a substance;

[0081] Step S203: Filter the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval, select the conversion rate range as 0-1, the conversion rate interval Δα=0.05, and filter out the temperature and time data corresponding to the conversion rate α=0, 0.05, 0.1, 0.15, 0.2, ..., 0.85, 0.9, 0.95, 1 in each group of experimental data.

[0082] Step S3: using the processed time and temperature data at the specified conversion rate level, perform minimization calculations to solve the activation energy and analyze the relationship between the activation energy and the substance reaction conversion rate;

[0083] The specific steps of step S3 are:

[0084] Step S301: Based on the processed time and temperature data at the specified conversion rate level, a solution formula for the reaction activation energy of the substance is constructed. The specific formula is:

[0085]

[0086] Among them, φ(E α ) represents the formula for solving the activation energy of the reaction of a substance, E α represents the reaction activation energy of the substance, i and j represent the data under different temperature control programs, n represents the number of experimental data groups, J[] represents the temperature integral term, T(t α ) represents the reaction temperature at time t when the conversion rate is α, t α represents the time point corresponding to the conversion rate α, which is used to determine the temperature integration range at this conversion rate, R represents the gas constant, which is a constant, exp() represents the exponential function, and T(t) represents the reaction temperature at time t;

[0087] The principle of the above formula is: This formula is based on the Arrhenius equation in chemical reaction kinetics. Under the constant conversion rate theory, for a given conversion rate interval Δα, the integral of the reaction rate constant J[E α ,T(t α )], can be established with the reaction activation energy E α , thus providing a basis for the subsequent solution of activation energy. Since the integral form is relatively complex, it cannot be solved directly under normal circumstances, so numerical methods such as Simpson integration are used for approximate calculations.

[0088] Step S302: using the Simpson integral solution formula to solve the temperature integral term, the specific formula is:

[0089]

[0090] When the selected conversion rate interval Δα is small enough, it can be considered that the reaction activation energy of the substance does not change within the short conversion rate change interval;

[0091] In this embodiment, Simpson integration is a numerical integration method, which uses a quadratic function to approximate the integrand, thereby improving the accuracy of integration to a certain extent. For the above-mentioned temperature integral term, due to the complexity of its exponential form, it is difficult to solve it by analytical method, so Simpson formula is used for approximate calculation;

[0092] Step S303: Substitute the solution of the temperature integral term into the solution formula of the reaction activation energy of the substance, and obtain the reaction activation energy E of the substance by minimizing the solution formula of the reaction activation energy of the substance. α .

[0093] In this embodiment, the basic idea of ​​calculating the activation energy of the reaction of the substance is to use the experimental data under different temperature control programs, and to construct a model about the activation energy E by comparing the differences in the temperature integral term J[] of different groups of data at the same conversion rate. α The solution formula φ(E α ), when φ(E α ) is the smallest, the corresponding E α The value is the reaction activation energy that best fits the experimental data. Statistical analysis and optimization based on multiple sets of experimental data can more accurately determine the reaction activation energy, because different temperature rise rate experiments can provide more comprehensive reaction information and reduce the error and uncertainty of a single experiment.

[0094] Step S4: performing isothermal process prediction according to the prediction equation to simulate the exothermic process;

[0095] The specific steps of step S4 are:

[0096] Step S401: According to thermodynamics and isoconversion theory, at a specified conversion rate level, the reaction activation energy of a substance is related to the reaction temperature, that is, under the same conversion rate conditions, the temperature integrals of different temperature control programs are equal. The temperature integral term J[] is extended to any temperature program. The specific formula is:

[0097]

[0098] in, The reaction time is The corresponding reaction temperature;

[0099] Step S402: construct a reaction time prediction equation, the specific formula is:

[0100]

[0101] Among them, t α represents the reaction time prediction equation, that is, the predicted reaction time at the conversion rate α, p and q represent the temperature control program of a certain experiment and the predicted temperature control program, respectively.

[0102] In this embodiment, the principle of the above formula is: the integral calculation of each fragment is performed and the sum is calculated to achieve the prediction of the whole reaction process time, and the predicted isothermal temperature is input. The calculated activation energy-conversion rate relationship, experimental data (here the experimental data corresponding to the median of the experimental temperature rise rate is selected as the numerator), and the integral calculation is also calculated using the Simpson integral formula to obtain the specified temperature The reaction time under the condition of isothermal process can be predicted.

[0103] Step S5: Calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics;

[0104] The specific formula for the heat release-time relationship of the substance under isothermal conditions in step S5 is:

[0105]

[0106] Among them, Q(t * ) represents the heat release-time relationship of a substance under isothermal conditions, that is, under isothermal conditions, t * The heat released at the time, Q0 represents the specific heat released by the substance in the experiment, represents the predicted reaction rate under isothermal conditions, as a function of time.

[0107] Step S6: Determine the packaging specifications and materials of the substance to be tested, and perform modeling;

[0108] Step S7: Obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

[0109] Determine the packaging model: Determine the packaging specifications and materials of the substance to be tested according to the "United Nations - Dangerous Goods Transport Regulations". The usual packaging specifications are: 0.5, 10, 25, 50kg (total weight of substance + packaging, with a mass error of ±1.5% allowed for the total packaging weight). After determining the packaging mass and material, calculate the packaging thickness and specific material loading based on the material density, packaging density and outer packaging size (a certain standard states that the maximum container loading for the transportation of hazardous chemicals shall not exceed 95% of the container volume).

[0110] According to the heat release-time relationship of the substance under isothermal conditions, combined with the substance volume model, the actual heat release of the substance in the package is calculated; after determining the specific size of the package, SolidWorks structure modeling is performed. The modeling model includes: the sample with determined size, the packaging shell, and the packaging shell cover, and the assembly components are used to assemble the substance to be tested-the outer packaging.

[0111] In this embodiment, a SADT experiment process simulation is provided:

[0112] Simulation theoretical basis: SADT definition: the lowest ambient temperature at which the reactive chemical substances in a specified package undergo self-accelerating decomposition within 7 days. Therefore, the ambient temperature Tenv can be set through thermal simulation to simulate the reaction process of the substance in the specified package, and observe whether the temperature at the center of the substance is higher than the ambient temperature by 6°C within 7 days. If so, it is considered that the substance has undergone self-accelerating decomposition in the specified package under the preset ambient temperature Tenv. At this time, the ambient temperature Tenv should be lowered, the isothermal condition prediction under Tenv should be re-performed, the heat release should be calculated, and the simulation should be re-performed; if the temperature at the center of the substance does not exceed the ambient temperature by 6°C within 7 days, the ambient temperature should be increased, the heat release should be calculated, and the simulation should be performed; the lowest ambient temperature at which the substance in the package undergoes self-accelerating decomposition is found by approximating the simulation temperature, which is the SADT of the substance under the package (there is a discrepancy with the flow chart here, and the solution method is mainly described here);

[0113] The temperature change of the substance-package at a specified temperature within 7 days is divided into two simulation steps:

[0114] 1) The process of heat transfer from the ambient temperature to the inside, and the temperature of the substance is consistent with that of the ambient temperature: set the ambient temperature Tenv as the heat source condition, perform transient thermal simulation, and record the time t1 when the center temperature of the sample is consistent with the ambient temperature according to the simulation results;

[0115] 2) The process of the material in the package being stored under Tenv, releasing heat and transferring heat to the outside: Take the simulation result of 1) as the initial condition, and import the heat release-time relationship of the material into the material as the internal heat generation heat load for simulation. According to the simulation results, record the time t2 corresponding to the central temperature of the sample being 6°C higher than the ambient temperature;

[0116] Calculate the reaction time. If t1+t2>7 days, it is considered that the substance has not undergone self-thermal decomposition under this temperature condition, and the isothermal temperature Tenv can be appropriately increased, and the heat release of the substance under the isothermal condition-time calculation is performed; if t1+t2<7 days, the isothermal temperature Tenv should be appropriately reduced, and the heat release calculation and thermal simulation should be performed again until the lowest ambient temperature for self-accelerating decomposition of the substance in the package is determined, which is the SADT of the substance under the package.

[0117] Example 2

[0118] See also Figure 4 , another embodiment provided by the present invention: a material self-accelerating decomposition temperature detection system, comprising: a data acquisition module, a screening module, an activation energy analysis module, a prediction module, a relationship analysis module, a packaging modeling module and a simulation solution module;

[0119] The data acquisition module is used to perform C80 calorimetric experiments on the substance to be tested at different temperature rise rates to obtain heat flow-time / heat flow-temperature data;

[0120] The screening module is used to construct a baseline according to the heat flow-time data, calculate the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and select the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data;

[0121] The activation energy analysis module is used to use the processed time and temperature data at the specified conversion rate level to perform minimization calculations, solve the activation energy, and analyze the relationship between the activation energy and the substance reaction conversion rate;

[0122] The prediction module is used to perform isothermal process prediction according to the prediction equation and simulate the exothermic process;

[0123] The relationship analysis module is used to calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics;

[0124] The packaging modeling module is used to determine the packaging specifications and materials of the substance to be tested and to perform modeling;

[0125] The simulation solution module is used to obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

[0126] The screening module comprises: a calculation unit and a screening unit;

[0127] The calculation unit is used to calculate the reaction conversion rate and reaction conversion rate of the substance based on the constructed baseline;

[0128] The screening unit is used to screen the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval.

[0129] The activation energy analysis module includes: a formula solving unit, a temperature integral solving unit and an activation energy solving unit;

[0130] The formula solving unit is used to construct a formula for solving the reaction activation energy of the substance based on the time and temperature data at the specified conversion rate level after processing;

[0131] The temperature integral solving unit is used to solve the temperature integral term by using the Simpson integral solving formula;

[0132] The activation energy solving unit is used to solve the reaction activation energy of the substance by minimizing the reaction activation energy solving formula of the substance.

[0133] In addition, the parts of the above-mentioned technical solutions provided in the embodiments of the present application that are consistent with the implementation principles of the corresponding technical solutions in the prior art are not described in detail to avoid excessive redundancy.

[0134] The specific implementation modes as described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation mode of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting the self-accelerating decomposition temperature of a substance, characterized in that: The specific steps include: Step S1: taking the material to be tested and performing a C80 calorimetric experiment at different temperature rise rates to obtain heat flow-time / heat flow-temperature data; Step S2: constructing a baseline according to the heat flow-time data, calculating the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and selecting the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data; Step S3: using the processed time and temperature data at the specified conversion rate level, perform minimization calculations to solve the activation energy and analyze the relationship between the activation energy and the substance reaction conversion rate; Step S4: performing isothermal process prediction according to the prediction equation to simulate the exothermic process; Step S5: Calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics; Step S6: Determine the packaging specifications and materials of the substance to be tested, and perform modeling; Step S7: Obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

2. A method for detecting the self-accelerating decomposition temperature of a substance as claimed in claim 1, characterized in that: The specific steps of step S2 are: Step S201: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is: Among them, α(t) represents the reaction conversion rate of the substance at time t, S(t) represents the heat flow signal at time t, W(t) represents the baseline at time t, t0 represents the initial time of the reaction, t represents any time after the start of the reaction, and t end Indicates the end time of the reaction; Step S202: Based on the constructed baseline, the reaction conversion rate of the substance is calculated. The specific formula is: Among them, α represents the reaction conversion rate of the substance, Indicates the reaction conversion rate of a substance; Step S203: Filter the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval, select the conversion rate range as 0-1, the conversion rate interval Δα=0.05, and filter out the temperature and time data corresponding to the conversion rate α=0, 0.05, 0.1, 0.15, 0.2, ..., 0.85, 0.9, 0.95, 1 in each group of experimental data.

3. A method for detecting the self-accelerating decomposition temperature of a substance as claimed in claim 2, characterized in that: The specific steps of step S3 are: Step S301: Based on the time and temperature data at the specified conversion rate level after processing, the reaction activation energy solution formula of the substance is calculated. The specific formula is: Among them, φ(E α ) represents the formula for solving the activation energy of the reaction of a substance, E α represents the reaction activation energy of the substance, i and j represent the data under different temperature control programs, n represents the number of experimental data groups, J[] represents the temperature integral term, T(t α ) represents the reaction temperature at time t when the conversion rate is α, t α represents the time point corresponding to the conversion rate α, R represents the gas constant, exp() represents the exponential function, and T(t) represents the reaction temperature at time t; Step S302: using the Simpson integral solution formula to solve the temperature integral term, the specific formula is: When the selected conversion rate interval Δα is small enough, it is determined that the reaction activation energy of the substance does not change within the short conversion rate change interval; Substitute the solution of the temperature integral term into the solution formula of the reaction activation energy of the substance, and obtain the reaction activation energy E of the substance by minimizing the solution formula of the reaction activation energy of the substance. α .

4. A method for detecting the self-accelerating decomposition temperature of a substance as claimed in claim 3, characterized in that: The specific steps of step S4 are: Step S401: According to thermodynamics and isoconversion theory, under the same conversion rate condition, the temperature integrals of different temperature control programs are equal. The temperature integral term J[] is extended to any temperature program. The specific formula is: in, The reaction time is The corresponding reaction temperature; Step S402: construct a reaction time prediction equation, the specific formula is: Among them, t α represents the reaction time prediction equation, i.e., the predicted reaction time at the conversion rate α, p and q represent the temperature control program of different experiments and the predicted temperature control program, respectively.

5. A method for detecting the self-accelerating decomposition temperature of a substance as claimed in claim 4, characterized in that: The specific formula of the heat release-time relationship of the substance under isothermal conditions in step S5 is: Among them, Q(t * ) represents the heat release-time relationship of a substance under isothermal conditions, that is, under isothermal conditions, t * The heat released at the time, Q0 represents the specific heat released by the substance in the experiment, represents the predicted reaction rate under isothermal conditions.

6. A material self-accelerating decomposition temperature detection system, used to implement a material self-accelerating decomposition temperature detection method according to any one of claims 1 to 5, characterized in that: include: Data acquisition module, screening module, activation energy analysis module, prediction module, relationship analysis module, packaging modeling module and simulation solution module; The data acquisition module is used to perform C80 calorimetric experiments on the substance to be tested at different temperature rise rates to obtain heat flow-time / heat flow-temperature data; The screening module is used to construct a baseline according to the heat flow-time data, calculate the reaction conversion rate and conversion rate of the substance based on the constructed baseline, and select the conversion rate calculation interval and conversion rate interval to screen the time and temperature of the experimental data; The activation energy analysis module is used to use the processed time and temperature data at the specified conversion rate level to perform minimization calculations, solve the activation energy, and analyze the relationship between the activation energy and the substance reaction conversion rate; The prediction module is used to perform isothermal process prediction according to the prediction equation and simulate the exothermic process; The relationship analysis module is used to calculate the heat release-time relationship of the substance under isothermal conditions according to the heat release characteristics; The packaging modeling module is used to determine the packaging specifications and materials of the substance to be tested and to perform modeling; The simulation solution module is used to obtain the self-accelerating decomposition temperature of the substance through experimental simulation.

7. A material self-accelerating decomposition temperature detection system as claimed in claim 6, characterized in that: The screening module comprises: a calculation unit and a screening unit; The calculation unit is used to calculate the reaction conversion rate and reaction conversion rate of the substance based on the constructed baseline; The screening unit is used to screen the processed conversion rate-temperature and conversion rate-time data according to the specified conversion rate interval.

8. A material self-accelerating decomposition temperature detection system as claimed in claim 7, characterized in that: The activation energy analysis module includes: a formula solving unit, a temperature integral solving unit and an activation energy solving unit; The formula solving unit is used to construct a formula for solving the reaction activation energy of the substance based on the time and temperature data at the specified conversion rate level after processing; The temperature integral solving unit is used to solve the temperature integral term by using the Simpson integral solving formula; The activation energy solving unit is used to solve the reaction activation energy of the substance by minimizing the reaction activation energy solving formula of the substance.

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