A garbage soil temperature data processing and analysis system and method based on water circulation pipe

Abstract

The present invention discloses a system and method for processing and analyzing landfill soil temperature data based on water circulation pipes. This system relates to the field of landfill soil temperature data processing. By utilizing the equivalent conversion theory of water circulation pipes and water walls, the present invention significantly improves the accuracy and efficiency of landfill soil temperature field calculations. First, the water wall equivalent model overcomes the computational limitations of traditional discrete pipes, achieving simplified calculations for continuous media through parametric derivation. Second, the unequal spacing model combined with a segmented processing method effectively addresses the modeling challenges of temporal and spatial differences in multi-layer circulation systems. Finally, the integration of dual-process simulations of cooling and reheating fully reveals the dynamic laws of landfill soil thermal response. This systematic modeling approach not only reduces computational complexity but also, through precise quantification of heat source terms, provides an important temperature control approach for landfill disaster prevention and control and thermal resource utilization, with significant engineering application value.

Description

Technical Field

[0001] The present invention belongs to the field of garbage soil temperature data processing, and in particular, relates to a garbage soil temperature data processing and analysis system and method based on a water circulation pipe. Background Art

[0002] The degradation of organic matter in landfill soil not only produces landfill gas and leachate, but also generates significant amounts of heat. The continuous accumulation of this heat causes the soil temperature to rise, negatively impacting the safety and stability of the landfill system. Therefore, the temperature variation of landfill soil is an important research topic. The deployment of water circulation pipes is one effective way to regulate the soil temperature. Studying the temperature variation of landfill soil under water circulation has important engineering significance and practical value.

[0003] Excessively high temperature of garbage soil will affect landfill gas production, liner system and landfill engineering quality, posing serious safety hazards to landfills. Summary of the Invention

[0004] In response to the problems in the related art, the present invention proposes a garbage soil temperature data processing and analysis system and method based on a water circulation pipe to overcome the above-mentioned technical problems existing in the existing related art.

[0005] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] The present invention provides a method for processing and analyzing garbage soil temperature data based on a water circulation pipe, comprising the following steps:

[0007] S1. Equivalent the water circulation pipe to a water wall; specifically, setting the basis for equivalent the water circulation pipe to a water wall and deriving the parameters for equivalent the water circulation pipe to a water wall, and obtaining the necessary and sufficient conditions for equivalent the water circulation pipe to a water wall;

[0008] S2. Calculate the final form of the heat source term of the garbage soil around the water wall according to the necessary and sufficient conditions for the equivalent of the water wall in the water circulation pipe;

[0009] S3. Construct an initial calculation model for the unequal spacing arrangement of water circulation pipes based on the multi-layer water circulation pipes. Then, in accordance with the necessary and sufficient conditions for the equivalence of water circulation pipes and water walls, each layer of water circulation pipes is segmented and described by dividing the water flow time. After the processing and description are completed, the final calculation model for the unequal spacing arrangement of water circulation pipes is obtained.

[0010] S4. Based on the final calculation model of the unequal spacing arrangement of water circulation pipes and the final form of the heat source term of the garbage soil around the water wall obtained in S2, and by constructing a garbage soil reheating model, the garbage soil cooling process and the reheating process are calculated respectively.

[0011] Preferably, the setting of the equivalent basis for the water circulation pipe water wall in S1 includes the following steps:

[0012] S111. Set an equivalence principle; the equivalence principle is that the average temperature of the garbage soil on any vertical plane at any time is equal.

[0013] Preferably, the derivation of parameters for water wall equivalence of the water circulation pipe in S1 comprises the following steps:

[0014] S121. Solve the average temperature of the water circulation pipe to obtain the average temperature solution of the water circulation pipe; as follows,

[0015] ;

[0016] ; ;

[0017] in, Indicates the initial temperature of water at the inlet of the water circulation pipe; represents the average temperature function of the water circulation pipe, m =0,1,2..., It indicates the initial temperature of garbage soil; x is the axial coordinate, Indicates time; l is the pipe length, is the thermal conductivity coefficient of garbage soil, is the density of garbage soil, is the attenuation coefficient;

[0018] S122, solving the water wall average temperature according to the water circulation pipe average temperature solution, and obtaining the water wall average temperature solution; as follows,

[0019] ;

[0020] in, A function representing the average temperature of the water wall;

[0021] S123. Construct the necessary and sufficient conditions for the average temperature of the garbage soil around the water circulation pipe and the water wall to be equal at any time and on any vertical plane before and after the water circulation pipe and the water wall are equivalent; as follows:

[0022] ; ; ; ;

[0023] in, represents the thermal conductivity of the garbage soil around the water wall; represents half of the water wall spacing, It represents half the width of the water wall; Indicates the radius of the water circulation pipe's influence area; is the thermal conductivity of the garbage soil around the water circulation pipe; is the radius of the water circulation pipe.

[0024] Preferably, the step S121 includes the following steps:

[0025] S1211. Set several basic assumptions to obtain a first basic assumption set; construct the first water circulation pipe equation, the second water circulation pipe equation, and the third water circulation pipe equation according to the first basic assumption set and the equivalent principle described in S111; they are as follows:

[0026] ;

[0027] Where: Any vertical plane of the water circulation pipe x The heat of the garbage soil; Any vertical plane of the water circulation pipe x The temperature of the garbage soil; Any vertical plane of the water circulation pipe x The average temperature of the garbage soil; For any vertical plane x The water temperature at is the density of garbage soil; is the specific heat capacity of the garbage soil; is the thermal conductivity of water;

[0028] S1212. Perform boundary condition homogenization on the first equation, the second equation, and the third equation of the water circulation pipe, and then use the separation of variables method to obtain the average temperature solution of the water circulation pipe.

[0029] Preferably, the S122 includes the following steps:

[0030] S1221. Set several basic assumptions to obtain a second set of basic assumptions; construct the first water wall equation, the second water wall equation, and the third water wall equation according to the first set of basic assumptions and the equivalent principle described in S111; they are as follows:

[0031] ; ; ;

[0032] in, Any vertical plane of the water wall x The heat of the garbage soil; Any vertical plane of the water wall x The temperature of the garbage soil; Any vertical plane of the water wall xThe average temperature of the garbage soil; z is the vertical coordinate of the water wall;

[0033] S1222. Perform boundary condition homogenization on the first water wall equation, the second water wall equation, and the third water wall equation, and then use the separation of variables method to obtain the average temperature solution of the water wall.

[0034] Preferably, said S2 comprises the following steps:

[0035] S21. Based on the necessary and sufficient condition that the average temperature of the garbage soil around the water wall and the water circulation pipe constructed in S123 is equal, the heat source term of the garbage soil around the water wall and the heat source term of the garbage soil around the water circulation pipe are calculated respectively; they are as follows:

[0036] ;

[0037] in, Indicates the heat generated per unit volume of garbage soil around the water wall; Indicates the temperature of the garbage soil around the water circulation pipe; Indicates the heat generated per unit volume of garbage soil around the water circulation pipe;

[0038] S22, according to the time required for the garbage soil around the water circulation pipe and the water wall to reach the peak heat generation, and then according to the heat generation source term of the garbage soil around the water wall and the heat generation source term of the garbage soil around the water circulation pipe, the final form of the heat generation source term of the garbage soil around the water wall is calculated; as follows,

[0039] ;

[0040] in, Indicates the time required for the garbage soil around the water circulation pipe to reach the peak heat generation; Indicates the peak heat generation rate of the garbage soil around the water circulation pipe.

[0041] Preferably, the step S3 includes the following steps:

[0042] S31, constructing an initial calculation model for the unequally spaced arrangement of water circulation pipes; the calculation model for the unequally spaced arrangement of water circulation pipes includes a first layer of water circulation pipes, a second layer of water circulation pipes, a third layer of water circulation pipes, and a fourth layer of water circulation pipes;

[0043] S32. Based on the necessary and sufficient condition that the average temperature of the garbage soil around the water circulation pipe and the water wall constructed in S123 is equal, each layer of water circulation pipes is equivalent to a water wall according to the horizontal and vertical spacing based on the first layer of water circulation pipes;

[0044] Set the first water flow time , calculated from the time water is just turned on to the time water is turned on Temperature changes of garbage soil in landfills within a time range;

[0045] S33, when the water flow time exceeds Finally, in S32, each layer of water circulation pipes is equivalent to a water wall according to the horizontal and vertical spacing. The one-dimensional heat conduction equation is used to describe the temperature changes of the garbage soil within the current water wall influence range, and the temperature changes of the garbage soil outside the bottom layer and the top layer of the water wall. After the description is completed, the final calculation model of the unequal spacing arrangement of water circulation pipes is obtained.

[0046] Preferably, in S33, using a one-dimensional heat conduction equation to describe the temperature change of the garbage soil within the current water wall influence range, and the temperature change of the garbage soil outside the bottom layer and the top layer of the water wall respectively includes the following steps:

[0047] S331, construct the control equation as follows:

[0048] ;

[0049] in, represents the thermal diffusion coefficient of garbage soil; They represent the peak heat generation rate of the garbage soil around the water wall and the time required for the garbage soil around the water wall to reach the peak heat generation rate;

[0050] S332, according to the temperature change of the garbage soil within the current water wall influence range, the control equation is solved in conjunction with the homogenization of the boundary conditions to obtain the first control equation solution; as follows,

[0051] ;

[0052] ;

[0053] in, For the i The eigenvalues ​​of the characteristic function; is the heat generation rate per unit volume of garbage soil per unit time; is the time-integrated variable; represents the initial temperature at the interface between the water wall and the garbage soil; They respectively represent the lower limit and upper limit of the range of influence of the water wall on the garbage soil; is the spatial characteristic function;

[0054] Then, based on the temperature changes of the garbage soil outside the bottom layer and the top layer of the water wall, the control equation is solved in conjunction with the temperature of the liner layer, the temperature of the geomembrane, and the homogenization of the boundary conditions to obtain the solution of the second control equation; as follows:

[0055] ;

[0056] ;

[0057] in, is the initial temperature distribution function of the garbage soil.

[0058] Preferably, the S4 comprises the following steps:

[0059] S41, calculating the garbage soil cooling process according to the control equation constructed in S331 and changing the heat source term therein;

[0060] S42, constructing a garbage soil reheating model; the control equation of the garbage soil reheating model is as follows:

[0061] ;

[0062] in, represents the initial temperature of the garbage soil; and then the garbage soil temperature regeneration model is used to calculate the garbage soil temperature regeneration process;

[0063] By coupling the calculation model of the cooling and rewarming processes, the entire process of garbage soil from forced cooling to natural rewarming is simulated, and the temperature prediction time span is extended by 3-5 times; it can accurately evaluate the heat exchange efficiency of the water circulation system, provide quantitative indicators for pumping energy consumption optimization, and reduce operating energy consumption; the rewarming model can predict the temperature rebound characteristics of garbage soil after the pump is stopped, identify environmental risks such as abnormal methane generation in advance, and improve the accuracy of early warning.

[0064] A garbage soil temperature data processing and analysis system based on water circulation pipes includes a water circulation pipe water wall equivalent module, a garbage soil heat source item calculation module, a water circulation pipe unequal spacing arrangement calculation model construction module, and a garbage soil return cooling calculation module.

[0065] The present invention has the following beneficial effects:

[0066] 1. This invention significantly improves the accuracy and efficiency of landfill soil temperature field calculations through the equivalent conversion theory of water circulation pipes and water walls. First, the water wall equivalent model breaks through the computational limitations of traditional discrete pipes and achieves simplified calculations of continuous media through parametric derivation. Second, the unequal spacing model combined with a segmented processing method effectively solves the modeling challenge of the temporal and spatial differences in multi-layer circulation systems. Finally, the integration of dual-process simulations of cooling and reheating fully reveals the dynamic laws of landfill soil thermal response. This systematic modeling approach not only reduces computational complexity but also provides an important temperature control method for landfill disaster prevention and control and thermal resource utilization through precise quantification of heat source terms, with significant engineering application value.

[0067] 2. In the present invention, in order to address the situation where the unequal spacing of water circulation pipes in the vertical direction leads to excessive related calculations, the equivalent conversion relationship between sand wells and sand walls in foundation treatment is referred to, and the equivalent principle that the average temperature of garbage soil is equal at any time and on any vertical plane is proposed to treat the water circulation pipes as water walls, and the relationship between the relevant parameters of the water circulation pipes and the water walls is obtained; based on the sand well-sand wall equivalent conversion theory, by establishing the average temperature equivalence principle, the problem of high computational complexity of discrete pipeline systems is effectively solved; secondly, the water wall treatment realizes the overall modeling of multi-layer unequally spaced pipes, avoiding the limitation of traditional methods that require pipe-by-pipe calculations; finally, the establishment of parameter correlation relationships provides a unified calculation framework for the thermodynamic analysis of garbage soil, which can simultaneously optimize the simulation accuracy of the cooling and reheating processes; this equivalent conversion method not only reduces the amount of calculation, but also provides key temperature data support for landfill leachate treatment and greenhouse gas control through accurate quantification of heat source terms.

[0068] 3. The treatment of the heat source term of the garbage soil around the water wall in the present invention is deduced based on the principle of conservation of heat generated by the garbage soil within the influence range of the water circulation pipe and the water wall before and after the equivalent, and finally the heat source term of the garbage soil around the water wall is determined; the form of the heat source term derived by the conservation principle more realistically reflects the coupling effect of heat generation from biodegradation of garbage soil and heat exchange in the pipeline, reducing the temperature field prediction error; it provides reliable temperature boundary conditions for processes such as landfill leachate treatment and biogas collection, and at the same time provides a methodological reference for equivalent modeling of heat sources in similar underground projects.

[0069] 4. In the present invention, the water circulation pipes are transformed into water walls by arranging the multiple water circulation pipes unevenly according to factors such as the external ambient temperature and the landfill depth, thereby approximately simplifying the non-axisymmetric problem into a one-dimensional temperature field problem.

[0070] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to more clearly illustrate the technical solutions of the embodiments of the invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0072] Figure 1 This is a simplified calculation diagram of the landfill water circulation pipe of the present invention; wherein: L is the calculated length of the water circulation pipe; r 、 x are the radial and axial coordinates respectively;

[0073] Figure 2 This is a simplified diagram for calculating the water wall of a landfill according to the present invention; wherein: L is the calculated length of the water wall, z w is half the width of the water wall, z a is half the distance between water walls, z , x are the vertical and axial coordinates respectively;

[0074] Figure 3 This is a schematic diagram of the calculation model of multiple water circulation pipes arranged at unequal intervals in the present invention. In the figure, there are four layers of water circulation pipes, numbered as the first, second, third, and fourth layers from bottom to top. The cushion layer is below the first layer, and the outside atmosphere is above the fourth layer. The horizontal arrangement spacing of water circulation pipes. S z1 、 S z2 and S z3 These are the vertical arrangement spacing of water circulation pipes. is the distance between the first layer of water circulation pipe and the lining layer, is the distance between the fourth layer of water circulation pipe and the outside atmosphere

[0075] Figure 4 This is a schematic diagram of the calculation of garbage soil between the first and second layers of the present invention;

[0076] Figure 5 This is a schematic diagram of the calculation of garbage soil between the second and third layers of the present invention;

[0077] Figure 6 The left and right figures in the middle are respectively schematic diagrams of the calculation of garbage soil below the first layer and the calculation of garbage soil above the fourth layer according to the present invention;

[0078] Figure 7 Schematic diagram of the change curve of garbage soil temperature with depth in the present invention;

[0079] Figure 8 It is a calculation diagram of the garbage soil reheating model of the present invention. DETAILED DESCRIPTION

[0080] The following will clearly and completely describe the technical solutions in the embodiments of the invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0081] Example 1

[0082] This embodiment is a method for processing and analyzing garbage soil temperature data based on a water circulation pipe, comprising the following steps:

[0083] 1 Equivalent relationship between water circulation pipe water wall;

[0084] 1.1 Equivalence basis of water circulation pipe water wall;

[0085] Referring to the sand wells used in foundation treatment, the horizontally spaced water circulation pipes are equated to continuous, uninterrupted horizontal water walls. Since the primary concern in actual landfills is the overall temperature variation of the landfill soil, the equivalence principle is that the average temperature of the landfill soil at any time and on any vertical plane is equal. This embodiment effectively transforms an axisymmetric temperature field problem into a one-dimensional temperature field problem in a Cartesian coordinate system.

[0086] 1.2 Derivation of parameters related to water wall formation in water circulation pipes;

[0087] 1.2.1 Calculate the average temperature of the water circulation pipe;

[0088] The water in the water circulation pipes in the landfill absorbs heat along the way, causing the water temperature to rise. This heat exchange mainly consists of two parts: heat conduction and heat convection. Heat conduction occurs between the garbage soil and the water, and heat convection is the transfer of heat from one end to the other as the water flows. Therefore, the landfill temperature problem is actually a three-dimensional coupled temperature field problem. The calculation diagram of the water circulation pipe in the landfill is shown in Figure 1 The basic assumptions adopted are as follows:

[0089] 1. In thermodynamics, an object with a unit mass absorbs (or releases) heat Δ in a certain process. Q When the temperature increases (or decreases) Δ T , then it is called Δ Q / Δ T is the specific heat capacity of the object, which is a constant value. Therefore, the heat change of the garbage soil on any vertical plane is proportional to the average temperature change of the garbage soil. After taking the derivative with respect to time, the heat change rate of the garbage soil is proportional to the average temperature change rate.

[0090] 2. In actual projects, the length of the water circulation pipe is much longer than the spacing between them. According to heat conduction theory, the speed of heat wave propagation in solids is proportional to the square of the distance. Since the spacing between the water circulation pipes is much smaller than their length, heat conduction between the garbage and soil during the cooling process mainly occurs in the plane perpendicular to the water circulation pipes. The temperature gradient of the garbage soil along the axial direction of the water circulation pipes can be approximately ignored. In other words, axial heat transfer is generally not considered, and radial heat transfer is considered according to the axisymmetric heat conduction differential equation.

[0091] 3. Due to the small diameter of the water circulation pipe, the radial change of the water temperature in the water circulation pipe is very small and can be ignored. The water temperature on the same vertical plane is assumed to be constant. If the heat loss is not considered, according to the principle of heat conservation, any vertical plane x The heat flowing from the garbage soil into the water circulation pipe along the pipe periphery is equal to the heat increment of the water in the water circulation pipe along the flow direction;

[0092] 4. The thermal resistance of the water circulation pipe has little effect on the temperature of the garbage soil and is not considered;

[0093] According to the above assumptions, only radial heat transfer is considered, and the following equation is obtained, that is,

[0094] (2.3)

[0095] (2.4)

[0096] (2.5)

[0097] Assume that the initial temperature of water at the inlet of the water circulation pipe is ;

[0098] (2.6)

[0099] Considering that the water temperature gradient at the outlet of the water circulation pipe is 0, the second type of boundary condition is adopted:

[0100] (2.7)

[0101] The thermal resistance of the water circulation pipe is not considered at the inner boundary of the garbage soil, so the temperature inside the garbage soil should be equal to the water temperature inside the water circulation pipe. , using the first type of boundary conditions:

[0102] (2.8)

[0103] The outer boundary is an adiabatic boundary, and the second type of boundary condition is adopted:

[0104] (2.9)

[0105] The initial temperature of garbage soil is :

[0106] (2.10)

[0107] Where: Any vertical plane of the water circulation pipe x The heat of the garbage soil; Any vertical plane of the water circulation pipe x The temperature of the garbage soil; Any vertical plane of the water circulation pipe x The average temperature of the garbage soil; For any vertical plane x The water temperature at is the density of garbage soil; is the specific heat capacity of the garbage soil; is the thermal conductivity of the garbage soil around the water circulation pipe; is the thermal conductivity of water;

[0108] The solution process is as follows:

[0109] First, the boundary conditions are homogenized, that is, , then the original equation becomes

[0110] (2.11)

[0111] (2.12)

[0112] (2.13)

[0113] The corresponding boundary conditions and initial conditions are transformed into

[0114] (2.14)

[0115] (2.15)

[0116] (2.16)

[0117] (2.17)

[0118] (2.18)

[0119] in, represents temperature; for both sides of equation (2.12) r Integrate and use the solution condition (2.17) to get

[0120] (2.19)

[0121] On both sides of the above equation, r Integrate and use the solution condition (2.16) to get

[0122] (2.20)

[0123] Then the average temperature of the garbage soil on any vertical plane is

[0124] (2.21)

[0125] Substituting equation (2.20) into equation (2.21), we get

[0126] (2.22)

[0127] Simplify, and we get

[0128] (2.23)

[0129] make , ,but

[0130] (2.24)

[0131] According to equation (2.19), equation (2.13) can be written as

[0132] (2.25)

[0133] Combining equations (2.11), (2.24) and (2.25), we get

[0134] (2.26)

[0135] (2.27)

[0136] Eliminate from equations (2.26) and (2.27) ,have to

[0137] (2.28)

[0138] Using the separation of variables method, let , then the general solution of formula (2.28) is

[0139] (2.29)

[0140] Where: 、 、 is the unknown coefficient, .

[0141] By solving conditions (2.14) and (2.15), we can get , .because 、 cannot be zero at the same time, so we need to make There is a non-zero solution, then Must be established.

[0142] then The special solution is

[0143] (2.30)

[0144] Where: , ( m =0,1,2,...), .

[0145] Superimposing all the special solutions, we get

[0146] (2.31)

[0147] Substituting equation (2.31) into equation (2.27), we get

[0148] (2.32)

[0149] According to the solution condition (2.18) , and use the function system ( m =0,1,2,...) in the interval Orthogonality on .

[0150] From equations (2.11), (2.20), (2.31) and (2.32), we can obtain the average temperature of the garbage soil that satisfies the basic equations and their solution conditions, namely:

[0151] (2.33)

[0152] 1.2.2 Calculation of average water wall temperature

[0153] For the equivalence between the water circulation pipe and the water wall, if we can ensure that the average temperature of the garbage soil in any vertical plane is equal at any time in both cases, we will have grasped the key aspects of the problem. In this section, when deriving the average temperature of the water wall, in order to facilitate the comparison between the two, the solution style and symbols are kept consistent with the previous section as much as possible. The calculation diagram of the water wall is shown in Figure 2 The basic assumptions are similar to those for water circulation pipes, as follows:

[0154] 1. The heat change of the garbage soil on any vertical plane is proportional to the average temperature change of the garbage soil. After taking the derivative with respect to time, the heat change rate of the garbage soil is proportional to the average temperature change rate.

[0155] 2. During the cooling process, heat conduction between the garbage and soil mainly occurs in the plane perpendicular to the water wall. The temperature gradient of the garbage and soil along the axial direction of the water wall can be approximately ignored. That is, axial heat transfer is generally not considered, and vertical heat transfer is considered according to the one-dimensional heat conduction differential equation.

[0156] 3. Due to the small width of the water wall, the vertical temperature variation of the water wall is very small and can be ignored. The water temperature on the same vertical plane is assumed to be constant. Ignoring heat loss, according to the principle of heat conservation, the heat flowing from the garbage soil along the wall into the water wall at any vertical plane x is equal to the heat increment of the water in the water wall along the flow direction.

[0157] 4. The thermal resistance of the water wall has little effect on the temperature of the garbage soil and is not considered.

[0158] According to the above assumptions, only vertical heat transfer is considered, and the following equation is obtained, that is,

[0159]

[0160] Assume that the initial temperature of water at the entrance of the water wall is :

[0161] (2.37)

[0162] Considering the water temperature gradient to be 0 at the water wall outlet, the second type of boundary condition is adopted:

[0163]

[0164] The thermal resistance of the water wall is not considered at the inner boundary of the garbage soil, so the temperature inside the garbage soil should be equal to the water temperature inside the water wall. , using the first type of boundary conditions:

[0165]

[0166] The outer boundary is an adiabatic boundary, and the second type of boundary condition is adopted:

[0167]

[0168] The initial temperature of garbage soil is :

[0169]

[0170] Where: Any vertical plane of the water wall x Heat of the garbage soil (J); Any vertical plane of the water wall x Temperature of the garbage soil (℃); Any vertical plane of the water wall x Average temperature of the garbage soil (℃); For any vertical plane x Water temperature at (℃); is the density of garbage soil (kg / m3); is the specific heat capacity of the garbage soil (J / (kg·℃)); is the thermal conductivity of the garbage soil around the water wall (W / (m·℃)); is the thermal conductivity of water (W / (m·℃)).

[0171] The solution process is as follows:

[0172] First, the boundary conditions are homogenized, that is, , then the original equation becomes

[0173]

[0174] The corresponding boundary conditions and initial conditions are transformed into

[0175]

[0176] For both sides of equation (2.43) z Integrate and use the solution condition (2.48) to get

[0177]

[0178] Then compare both sides of the above formula with z Integrate and use the solution condition (2.47) to get

[0179]

[0180] Then the average temperature of the garbage soil on any vertical plane is

[0181]

[0182] Simplify, and we get

[0183]

[0184] From equation (2.50), equation (2.44) can be written as

[0185]

[0186] Combining equations (2.42), (2.53) and (2.54), we get

[0187]

[0188] Eliminate from equations (2.55) and (2.56) ,have to

[0189]

[0190] Using the separation of variables method, let , then the general solution of formula (2.57) is

[0191]

[0192] Where: 、 、 is the unknown coefficient, .

[0193] By solving conditions (2.45) and (2.46), we can get , .because 、 cannot be zero at the same time, so we need to make There is a non-zero solution, then Must be established.

[0194] then The special solution is

[0195]

[0196] Where: , ( m =0,1,2,...), .

[0197] Superimposing all the special solutions, we get

[0198]

[0199] Substituting equation (2.60) into equation (2.56), we get

[0200]

[0201] By solving condition (2.49), and using the function system ( m =0,1,2,...) in the interval Orthogonality on .

[0202] From equations (2.42), (2.51), (2.60) and (2.61), we can get the average temperature of the garbage soil that satisfies the basic equation and its solution conditions, that is,

[0203]

[0204] 1.2.3 Equivalence of water circulation pipe and water wall

[0205] If you use subscript a Indicates water circulation pipe, subscript p represents the water wall, then the average temperature of the garbage soil on any vertical plane of the water circulation pipe is obtained from the above derivation process: ,

[0206]

[0207] in: .

[0208] Average temperature of garbage soil on any vertical plane of the water wall for

[0209]

[0210] in: .

[0211] To make the water circulation pipe and the water wall equivalent, the average temperature of the garbage soil on any vertical plane at any time should be equal, that is, Since the average temperature of the waste soil around the water circulation pipe and the water wall is expressed in the same way, only the parameters are different, only Then, we can further obtain

[0212]

[0213] Arranging formula (2.65), we can get

[0214]

[0215] because For variables, only , Only when both are established at the same time can we ensure that formula (2.66) always holds.

[0216]

[0217] Combining equations (2.67) and (2.68), we can get

[0218]

[0219] Equations (2.69) and (2.70) are necessary and sufficient conditions to ensure that the average temperature of the waste soil around the water circulation pipe and the water wall is equal at any time and on any vertical plane before and after equivalence. In order to best reflect the actual cooling situation of the water circulation pipe, the spacing between the water walls should be equal to the vertical spacing of the water circulation pipe, that is, , and then use equations (2.69) and (2.70) to solve for half the thickness of the water wall Thermal conductivity of garbage soil around the water wall In this way, a corresponding relationship between the water circulation pipe and the water wall is established.

[0220] Since the water circulation pipe and the water wall follow the principle that the average temperature of the garbage soil on any vertical plane at any time is equal, the temperature change trend and heat generation trend of the garbage soil around the water wall should be the same as those in the water circulation pipe. In other words, the heat generation rate curve and total heat generation curve of the garbage soil in the water wall should also be consistent with the change trend in the water circulation pipe. Therefore, the following equation can also be used for fitting:

[0221]

[0222] in (J / h) and (h) is the parameter value. Since there is no actual on-site measurement data, other methods need to be used to derive the parameters.

[0223] Since the equivalence principle between the water circulation pipe and the water wall is that the average temperature of the garbage soil on any vertical plane is equal at any time, the corresponding heat source items of the two should ensure heat conservation before and after equivalence, that is, the heat generated by the garbage soil within the influence range corresponding to the water circulation pipe and the water wall at any time is the same, and after taking the time derivative, the heat generation rate should also be the same.

[0224] The heat generation equation itself represents the heat generated by the degradation of garbage soil. According to the total heat generation equation (2.71), we can get The heat generated by unit volume of garbage soil around the water wall during this time is

[0225]

[0226] and ,have

[0227]

[0228] Divide both sides by , and simplify, when When it is very small, there is

[0229]

[0230] Then the heat source term of the garbage soil around the water wall is

[0231]

[0232] Volume of garbage soil within the influence range of the water wall , then the total heat generated by the garbage soil is

[0233]

[0234] The existing literature gives the heat generation per unit volume of garbage soil around the water circulation pipe as

[0235]

[0236] and ,have

[0237]

[0238] Divide both sides by , and simplify, when When it is very small, there is

[0239]

[0240] Then the heat source term of the garbage soil around the water circulation pipe is

[0241]

[0242] Volume of garbage soil within the influence range of water circulation pipe , then the total heat generated by the garbage soil is

[0243]

[0244] Since the heat generated by the garbage soil around the water circulation pipe and the water wall must satisfy the heat conservation law, let Equation (2.76) and Equation (2.81) be equal, then

[0245]

[0246] Divide both sides by , and simplify, when When it is very small, there is

[0247]

[0248] Will and About time t After taking the derivative, we substitute into equations (2.80) and (2.75) to get

[0249]

[0250] Combining equations (2.83), (2.84) and (2.85), we can get

[0251]

[0252] in, and The physical meanings of are the peak heat generation rate of garbage soil around the water circulation pipe and water wall, and The physical meaning of is the time required for the garbage soil around the water circulation pipe and the water wall to reach the peak heat generation. Since the average temperature of the garbage soil around the water circulation pipe and the water wall is equal at any time, the time required for the garbage soil around the water circulation pipe and the water wall to reach the peak heat generation should be the same, that is, , substitute equation (2.2) into equation (2.86) and simplify, and we get

[0253]

[0254] From this, we can know that the relationship between the heat source parameters of the water circulation pipe and the garbage soil around the water wall is:

[0255]

[0256] 2. Working conditions of unequal spacing arrangement of water circulation pipes

[0257] 2.1 Approximate analysis method based on existing models

[0258] Due to the influence of factors such as external ambient temperature and landfill depth on the temperature of garbage soil, it is necessary to arrange water circulation pipes at non-uniform intervals in the vertical direction to achieve the purpose of improving efficiency and saving resources. The maximum temperature of the external atmosphere rarely exceeds 40℃, which is much lower than the maximum temperature of garbage soil in some landfills. Therefore, for garbage soil in the shallow layer of the landfill, the external atmosphere also has a cooling effect on it. Therefore, as the depth of the garbage soil in the landfill increases, the vertical arrangement spacing of the water circulation pipes should be gradually reduced. The calculation diagram is shown in Figure 3 .

[0259] exist Figure 3 The vertical arrangement spacing of the water circulation pipes increases from bottom to top, that is, , and the distance between the first layer of water circulation pipe and the liner layer, as well as the distance between the fourth layer of water circulation pipe and the outside atmosphere are greater than the distance between the first and second layers of water circulation pipes, that is, , It is assumed that after a period of water flow, the first and second layers of water circulation pipes can affect the garbage soil between the two layers. The reason for this assumption is that if the garbage soil between the two layers of water circulation pipes still cannot be affected after a long period of water flow, it means that the vertical spacing of the water circulation pipes is too large. To meet actual cooling needs, the spacing needs to be reduced.

[0260] This condition is a non-axisymmetric temperature field problem. Equation (2.2) cannot be used directly to determine the influence range of the water circulation pipe, nor can it be simplified directly using a water wall. Non-axisymmetric temperature problems are difficult to solve directly, so other methods are needed to approximate them.

[0261] This example will focus on analyzing Figure 3The water circulation pipes and garbage soil within the medium-thick line can be extended to the entire landfill. The following are the solutions to this problem:

[0262] Step 1: Based on the first layer of water circulation pipes, that is, according to the equivalent relationship between the water circulation pipes and the water wall, each layer of water circulation pipes is arranged at a horizontal spacing. and vertical spacing Simplified to a water wall, such as Figure 4 As shown. It is easy to know that as the water flow time increases, the influence range of the water wall will continue to expand, so the water flow time can be calculated. , the water wall happens to affect , from which we can get the The temperature variation of the garbage soil in the landfill within the time range is the same as that when the water circulation pipes are evenly arranged;

[0263] Step 2: Discuss the time it takes for water to flow Temperature changes of garbage soil between the second and third layers of water walls: Take the garbage soil between the second and third layers of water walls as an example. Figure 5 When the water flow time exceeds After that, the water wall will affect the area beyond the thick dotted line. Since the water circulation pipe has been simplified to a water wall, the two-dimensional temperature field problem has been simplified to a one-dimensional temperature field problem. The temperature change of the garbage soil within the enclosure can be described by a one-dimensional heat conduction equation.

[0264] Governing equations:

[0265]

[0266] Assume that the initial temperature of the garbage soil is , because in the water When the water wall has not yet affected the garbage soil within the range, the initial condition should be set as the natural degradation of the garbage soil. Temperature after time:

[0267]

[0268] The inner boundary should be the outer boundary of the water wall in the first step The temperature of the garbage soil at is the starting time, which changes continuously with time to ensure the continuity of temperature:

[0269]

[0270] Since the outer boundary is located between two water walls, it should be affected equally by the two water walls. Therefore, an adiabatic condition is adopted, with no heat exchange and a temperature gradient of 0:

[0271]

[0272] The temperature changes of the garbage soil between the third and fourth water circulation pipes can be analyzed according to the above steps.

[0273] See Figure 6 , Step 3: Discuss the water flow time exceeding Temperature changes of the garbage soil outside the bottom and top water walls: The analysis method is similar to that in the second step. The control equations and initial and internal boundary conditions are the same as those in the second step, but the external boundary conditions are different.

[0274] For waste soil below the first layer, the external boundary condition should be set to the temperature of the liner layer:

[0275]

[0276] For the fourth layer of garbage soil and above, the outer boundary condition should be set to the temperature of the outside atmosphere:

[0277]

[0278] The above is an approximate analysis method for the problem of unequal spacing of water circulation pipes. No matter how many layers the water circulation pipes are arranged, they can be approximated using the above method.

[0279] 2.2 Calculation of garbage soil cooling based on approximate method

[0280] Since the equations involved in this approximate analysis method are coupled and difficult to solve directly, COMSOL Multiphysics software is used for analysis. The temperature drop of the garbage soil around the four-layer water circulation pipe is calculated. The specific parameters and values ​​are shown in Table 1; as follows,

[0281] Table 1 Parameters and values ​​required for calculation

[0282]

[0283] If the landfill surface is taken as the horizontal reference plane, the distribution of the garbage soil temperature between the bottom water circulation pipe and the landfill surface is calculated by COMSOL after 6 months, 1 year, 2 years and 5 years of water supply, as shown in the following figure: Figure 7 shown.

[0284] Depend on Figure 7 The following conclusions can be drawn:

[0285] (1) Taking the curve of 6 months of water supply as an example, it can be found that the smaller the spacing between the water circulation pipes, the greater the impact of the water circulation pipes on the temperature of the garbage soil, and the faster the garbage soil cools down;

[0286] (2) The temperature rise of the garbage soil closer to the water wall due to self-degradation is not enough to offset the cooling effect of the water cycle, and the temperature of the garbage soil decreases; while the garbage soil farther from the water wall takes a long time to be affected by the cooling effect of the water cycle, and its own degradation temperature rise plays a dominant role. Therefore, there is no obvious temperature drop phenomenon within the calculation time, but as time goes by, the temperature of the garbage soil farther away will inevitably decrease;

[0287] (3) The external atmosphere will affect the temperature of the garbage soil, and the degree of influence will increase over time. However, in actual working conditions, the temperature of the external atmosphere is constantly changing. In order to simplify the calculation, this embodiment takes the atmospheric temperature as a constant value.

[0288] 3 Calculation of the cooling process of garbage soil

[0289] 3.1 Cooling calculation based on the on-site multi-water circulation pipe model

[0290] The present invention establishes a multi-water circulation pipe model, which simulates the temperature change of the surrounding garbage soil under the action of the multi-water circulation pipe.

[0291] The governing equations of the model are:

[0292]

[0293] Initial conditions and internal and external boundary conditions:

[0294]

[0295] The temperature of the garbage soil is lowered to a range suitable for its degradation or gas production by water circulation. It is assumed that the temperature of the garbage soil is cooled by water circulation after it stabilizes. The temperature of the garbage soil reaches its maximum value after about one year and remains stable. The temperature is about 39.2℃ when it is stable. If water is passed through the system to cool it down at this time, the heat source term and the initial condition value in the control equation need to be changed. Because the temperature of the garbage soil stabilizes after one year, the time of the heat source term in the equation needs to be changed. In units of hours (h), the time t becomes ( t +8760), at which time the landfill soil degradation is basically complete, and the influence of the heat source on the landfill soil temperature can be ignored in subsequent calculations using the model. The initial condition of the equation becomes the temperature of the landfill soil after one year of degradation, that is, The circulating water temperature is 39.2℃ It is still 15.5℃, and it is assumed that the temperature of water when it flows out of the garbage soil is equal to the temperature when it flows in. In fact, due to heat conduction between water and garbage soil and heat convection during the flow process, the temperature of water when it flows out is slightly higher than the temperature when it flows in. However, because the temperature change law of garbage soil is mainly studied when calculating the cooling process of garbage soil, the water temperature in the water circulation pipe is assumed to be a constant value, which is conducive to simple calculation. In addition, according to field tests, the inlet and outlet temperatures of circulating water are not much different, so it can be ignored.

[0296] According to the existing calculation results, the impact range of a single water circulation pipe is found two years later. It can reach 6m, if the multiple water circulation pipes are arranged in a rectangular shape and the horizontal spacing is and vertical spacing When the length of each water circulation pipe is 10.3m, the influence range of each water circulation pipe is 6m. The multiple water circulation pipes are simplified into water walls for approximate calculation. At this time, the thickness of the water wall is 2 z w =0.0018m, spacing 2 z a =10.3m, the corresponding heat conductivity coefficient of garbage soil =0.0275(W / (m·K)), taking the garbage soil at 0.5m, 1m, 2m, 3m and 5m vertically away from the water wall as calculation points, and using this model to calculate the change process of garbage soil temperature within one year and two years;

[0297] 4 Calculation of garbage soil reheating process

[0298] 4.1 Analysis of the temperature recovery pattern of garbage soil

[0299] The process of garbage soil warming up is as follows: after water has been flowing through the water circulation pipe for a period of time, the average temperature of the garbage soil will drop to a certain value. If the water circulation is stopped at this time, due to the lack of the cooling effect of the water circulation, the higher temperature of the garbage soil farther away from the water circulation pipe will transfer heat to the lower temperature of the garbage soil closer to the water circulation pipe, causing the temperature of the garbage soil that has previously cooled down to rise again.

[0300] Figure 8 This is a schematic diagram of the calculation of the garbage soil reheating model. Assume that the influence of the water circulation system on the garbage soil is within Within the affected area, the temperature of the garbage soil is relatively low due to water cooling, especially the garbage soil temperature near the water circulation pipe is almost equal to the water temperature. However, the garbage soil outside the affected area is far away from the water circulation pipe, and the water circulation system has basically not affected this area, so the temperature of the garbage soil outside the affected area is still kept at a relatively high state.

[0301] The governing equations of the model at this time are:

[0302]

[0303] Initial conditions:

[0304]

[0305] Since the inner boundary is not permeable to water, an adiabatic boundary is used:

[0306]

[0307] The outer boundary is assumed to be constant temperature, and the first type of boundary condition is used:

[0308]

[0309] in: t 0 is the time (h) for cooling water through the water circulation pipe. Since the time required to cool the garbage soil to different temperatures is different, the control equation t 0 is also different. For the outer boundary condition, the outer boundary temperature after the water circulation pipe is cooled is more accurate, and this temperature should be lower than the temperature when the landfill soil is degraded. However, for the convenience of the solution, the temperature when the landfill soil is degraded is used as the outer boundary temperature for simplified calculation.

[0310] Taking the first water supply situation as an example, the water circulation pipes are arranged at a distance of 10.3m. After the average temperature of the garbage soil drops to 30℃, the water supply is stopped and the subsequent temperature rise process of the garbage soil is calculated using the temperature recovery model. t 0 is 6.63 years, which needs to be converted into hours.

[0311] Example 2

[0312] This embodiment discloses a garbage soil temperature data processing and analysis system based on water circulation pipes. The system can implement the method of the above embodiment and includes a water circulation pipe water wall equivalent module, a garbage soil heat source term calculation module, a water circulation pipe unequal spacing arrangement calculation model construction module, and a garbage soil return temperature calculation module.

[0313] The water circulation pipe water wall equivalent module equates the water circulation pipe to a water wall; specifically, it includes setting the water circulation pipe water wall equivalent basis and deriving the parameters for the water circulation pipe water wall equivalent, and obtaining the necessary and sufficient conditions for the water circulation pipe water wall equivalent;

[0314] The heat source term calculation module of the garbage soil calculates the final form of the heat source term of the garbage soil around the water wall according to the necessary and sufficient conditions for the equivalent of the water wall of the water circulation pipe;

[0315] The water circulation pipe unequal spacing arrangement calculation model construction module constructs an initial water circulation pipe unequal spacing arrangement calculation model based on multiple layers of water circulation pipes; then, in accordance with the necessary and sufficient conditions for water circulation pipe water wall equivalence, each layer of water circulation pipes is segmented and described by dividing the water flow time; after the processing and description are completed, the final water circulation pipe unequal spacing arrangement calculation model is obtained;

[0316] The garbage soil cooling and reheating calculation module calculates the garbage soil cooling process and the reheating process respectively according to the final water circulation pipe unequal spacing arrangement calculation model and the final form of the heat source term of the garbage soil around the water wall obtained in S2, and by constructing a garbage soil reheating model.

[0317] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0318] The preferred embodiments of the invention disclosed above are intended only to help illustrate the invention. These preferred embodiments do not exhaust all details, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A method for processing and analyzing landfill soil temperature data based on a water circulation pipe, characterized in that: The following steps are involved: S1. Equivalent the water circulation pipe to a water wall; specifically, setting the basis for equivalent the water circulation pipe to a water wall and deriving the parameters for equivalent the water circulation pipe to a water wall, and obtaining the necessary and sufficient conditions for equivalent the water circulation pipe to a water wall; The derivation of the parameters for water wall equivalent of the water circulation pipe described in S1 includes the following steps: S121. Solve the average temperature of the water circulation pipe to obtain the average temperature solution of the water circulation pipe; as follows, ； ； ； in, Indicates the initial temperature of water at the inlet of the water circulation pipe; represents the average temperature function of the water circulation pipe, m =0,1,2..., It indicates the initial temperature of garbage soil; x is the axial coordinate, Indicates time; l is the pipe length, is the thermal conductivity coefficient of garbage soil, is the density of garbage soil, is the attenuation coefficient; S122, solving the water wall average temperature according to the water circulation pipe average temperature solution, and obtaining the water wall average temperature solution; as follows, ； in, A function representing the average temperature of the water wall; S123. Construct the necessary and sufficient conditions for the average temperature of the garbage soil around the water circulation pipe and the water wall to be equal at any time and on any vertical plane before and after the water circulation pipe and the water wall are equivalent; as follows: ； ； ； ； in, represents the thermal conductivity of the garbage soil around the water wall; represents half of the water wall spacing, It represents half the width of the water wall; Indicates the radius of the water circulation pipe's influence area; is the thermal conductivity of the garbage soil around the water circulation pipe; is the radius of the water circulation pipe; S2. Calculate the final form of the heat source term of the garbage soil around the water wall according to the necessary and sufficient conditions for the equivalent of the water wall in the water circulation pipe; Specifically include: S21. Based on the necessary and sufficient condition that the average temperature of the garbage soil around the water wall and the water circulation pipe constructed in S123 is equal, the heat source term of the garbage soil around the water wall and the heat source term of the garbage soil around the water circulation pipe are calculated respectively; they are as follows: ； in, Indicates the heat generated per unit volume of garbage soil around the water wall; Indicates the temperature of the garbage soil around the water circulation pipe; Indicates the heat generated per unit volume of garbage soil around the water circulation pipe; S22, according to the time required for the garbage soil around the water circulation pipe and the water wall to reach the peak heat generation, and then according to the heat generation source term of the garbage soil around the water wall and the heat generation source term of the garbage soil around the water circulation pipe, the final form of the heat generation source term of the garbage soil around the water wall is calculated; as follows, ； in, Indicates the time required for the garbage soil around the water circulation pipe to reach the peak heat generation; Indicates the peak heat generation rate of garbage soil around the water circulation pipe; S3. Construct an initial calculation model for the unequal spacing arrangement of water circulation pipes based on the multi-layer water circulation pipes. Then, in accordance with the necessary and sufficient conditions for the equivalence of water circulation pipes and water walls, each layer of water circulation pipes is segmented and described by dividing the water flow time. After the processing and description are completed, the final calculation model for the unequal spacing arrangement of water circulation pipes is obtained. S4. Based on the final calculation model of the unequal spacing arrangement of water circulation pipes and the final form of the heat source term of the garbage soil around the water wall obtained in S2, and by constructing a garbage soil reheating model, the garbage soil cooling process and the reheating process are calculated respectively.

2. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 1, characterized in that: The equivalent basis for setting the water circulation pipe water wall in S1 includes the following steps: S111. Set an equivalence principle; the equivalence principle is that the average temperature of the garbage soil on any vertical plane at any time is equal.

3. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 2, characterized in that: The S121 includes the following steps: S1211. Set several basic assumptions to obtain a first basic assumption set; construct the first water circulation pipe equation, the second water circulation pipe equation, and the third water circulation pipe equation according to the first basic assumption set and the equivalent principle described in S111; they are as follows: ； ； ； Where: Any vertical plane of the water circulation pipe x The heat of the garbage soil; Any vertical plane of the water circulation pipe x The temperature of the garbage soil; Any vertical plane of the water circulation pipe x The average temperature of the garbage soil; For any vertical plane x The water temperature at is the density of garbage soil; is the specific heat capacity of the garbage soil; is the thermal conductivity of water; S1212. Perform boundary condition homogenization on the first equation, the second equation, and the third equation of the water circulation pipe, and then use the separation of variables method to obtain the average temperature solution of the water circulation pipe.

4. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 3 is characterized in that: The S122 includes the following steps: S1221. Set several basic assumptions to obtain a second set of basic assumptions; construct the first water wall equation, the second water wall equation, and the third water wall equation according to the first set of basic assumptions and the equivalent principle described in S111; they are as follows: ； ； ； in, Any vertical plane of the water wall x The heat of the garbage soil; Any vertical plane of the water wall x The temperature of the garbage soil; Any vertical plane of the water wall x The average temperature of the garbage soil; z is the vertical coordinate of the water wall; S1222. Perform boundary condition homogenization on the first water wall equation, the second water wall equation, and the third water wall equation, and then use the separation of variables method to obtain the average temperature solution of the water wall.

5. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 4 is characterized in that: The S3 includes the following steps: S31, constructing an initial calculation model for the unequally spaced arrangement of water circulation pipes; the calculation model for the unequally spaced arrangement of water circulation pipes includes a first layer of water circulation pipes, a second layer of water circulation pipes, a third layer of water circulation pipes, and a fourth layer of water circulation pipes; S32. Based on the necessary and sufficient condition that the average temperature of the garbage soil around the water circulation pipe and the water wall constructed in S123 is equal, each layer of water circulation pipes is equivalent to a water wall according to the horizontal and vertical spacing based on the first layer of water circulation pipes; Set the first water flow time , calculated from the time water is just turned on to the time water is turned on Temperature changes of garbage soil in landfills within a time range; S33, when the water flow time exceeds Finally, in S32, each layer of water circulation pipes is equivalent to a water wall according to the horizontal and vertical spacing. The one-dimensional heat conduction equation is used to describe the temperature changes of the garbage soil within the current water wall influence range, and the temperature changes of the garbage soil outside the bottom layer and the top layer of the water wall. After the description is completed, the final calculation model of the unequal spacing arrangement of water circulation pipes is obtained.

6. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 5, characterized in that: In S33, a one-dimensional heat conduction equation is used to describe the temperature changes of the garbage soil within the current water wall influence range, the temperature changes of the garbage soil outside the bottom layer and the top layer of the water wall, respectively, including the following steps: S331, construct the control equation as follows: ； in, represents the thermal diffusion coefficient of garbage soil; They represent the peak heat generation rate of the garbage soil around the water wall and the time required for the garbage soil around the water wall to reach the peak heat generation rate; S332, according to the temperature change of the garbage soil within the current water wall influence range, the control equation is solved in conjunction with the homogenization of the boundary conditions to obtain the first control equation solution; as follows, ； ； in, For the i The eigenvalues ​​of the characteristic function; is the heat generation rate per unit volume of garbage soil per unit time; is the time-integrated variable; represents the initial temperature at the interface between the water wall and the garbage soil; They respectively represent the lower limit and upper limit of the range of influence of the water wall on the garbage soil; is the spatial characteristic function; Then, based on the temperature changes of the garbage soil outside the bottom layer and the top layer of the water wall, the control equation is solved in conjunction with the temperature of the liner layer, the temperature of the geomembrane, and the homogenization of the boundary conditions to obtain the solution of the second control equation; as follows: ； ； in, is the initial temperature distribution function of the garbage soil.

7. The method for processing and analyzing landfill soil temperature data based on a water circulation pipe according to claim 6, characterized in that: The S4 comprises the following steps: S41, calculating the garbage soil cooling process according to the control equation constructed in S331 and changing the heat source term therein; S42, constructing a garbage soil reheating model; the control equation of the garbage soil reheating model is as follows: ； in, represents the initial temperature of the garbage soil; and then the garbage soil reheating model is used to calculate the garbage soil reheating process.

8. A garbage soil temperature data processing and analysis system based on a water circulation pipe, characterized by: Used to implement a garbage soil temperature data processing and analysis method based on a water circulation pipe as described in any one of claims 1-7.

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