CN-122014296-A - Roadway tunnel structure for compressed air energy storage and transformation method

CN122014296ACN 122014296 ACN122014296 ACN 122014296ACN-122014296-A

Abstract

The invention discloses a tunnel cave structure for compressed air energy storage and a transformation method, wherein the tunnel cave structure comprises a surrounding rock body which is reinforced by support; the phase-change concrete lining layer is attached to the inner wall of the surrounding rock body, and the sealing layer is paved on the inner surface of the phase-change concrete lining layer. The transformation method comprises the steps of determining the loosening ring range of the surrounding rock of the roadway cave to be transformed, expanding and digging the roadway cave to be transformed into a preset shape by taking the outer boundary of the loosening ring as the outline, supporting and reinforcing the expanded surrounding rock of the roadway cave, constructing a phase-change concrete lining layer on the surface of the supported surrounding rock, and paving the sealing layer on the surface of the phase-change concrete lining layer. The invention improves the mechanical stability and air tightness of the tunnel and the cave, and ensures that the tunnel and the cave can be used for a compressed air energy storage system.

Inventors

LI YINGSHUN
HUANG YANLI
LI JUNMENG
OUYANG SHENYANG
YANG CHAOGE
LIU JIACHEN
Ding Zizhao

Assignees

中国矿业大学

Dates

Publication Date: 20260512
Application Date: 20260209

Claims (8)

1. The utility model provides a roadway cave structure for compressed air energy storage which characterized in that, roadway cave structure includes from outside to inside in proper order: the surrounding rock body is reinforced by support; the phase-change concrete lining layer is attached to the inner wall of the surrounding rock body, and the sealing layer is paved on the inner surface of the phase-change concrete lining layer; the phase-change concrete lining layer stores and releases heat through a phase-change process, maintains the temperature stability of surrounding rock and supplements heat for gas in the release stage.
2. The roadway tunnel structure for compressed air energy storage of claim 1, wherein the cross section of the roadway tunnel structure is circular, and the radius of the circular shape is not less than the maximum loose coil radius of the surrounding rock mass.
3. The roadway tunnel structure for compressed air energy storage of claim 1, wherein the performance parameters and the satisfied conditions of the phase-change concrete lining layer comprise: Compressive strength of phase-change concrete: ; Wherein, sigma c is the compressive strength of the phase-change concrete, sigma 0 is the stress of the original rock, and sigma g_max is the maximum gas pressure when compressed air stores energy; phase transition temperature of phase transition concrete: ; wherein T 1 is the temperature of the raw rock, Is the phase transition temperature; The heat storage capacity of the phase-change concrete is larger than the heat release capacity of the single compressed air energy storage and inflation stage, and the phase-change enthalpy and construction thickness of the phase-change concrete are as follows: ; Wherein ρL is the phase change enthalpy of the phase change concrete, L is the unit length, A is the inner surface area of the phase change concrete, d is the thickness of the phase change concrete, n 1 is the total air mass under standard atmospheric pressure, n 2 is the total air mass under maximum gas pressure, P 1 is the standard atmospheric pressure, P 2 is the maximum gas pressure, V is the area of the tunnel section after the phase change concrete is laid, and R is the ideal gas constant.
4. A modification method applied to the roadway tunnel structure as claimed in any one of claims 1 to 3, comprising: determining the loose circle range of the surrounding rock of the tunnel cave to be reformed; The outer boundary of the loose ring is taken as a contour, and a roadway cave to be reformed is enlarged, dug and trimmed into a preset shape; supporting and reinforcing the tunnel cave surrounding rock after the expansion and excavation; constructing a phase-change concrete lining layer on the surface of the supported surrounding rock; And paving the sealing layer on the surface of the phase-change concrete lining layer.
5. The improvement as set forth in claim 4 wherein said determination of the loose coil range of said roadway chamber surrounding rock to be improved is: ; Wherein R p is the radius of the loose coil, R 0 is the radius of the roadway, sigma 0 is the stress of the original rock, P i is the supporting resistance provided by the existing supporting on the roadway wall, S is the cohesive force of the surrounding rock, and phi is the internal friction angle of the surrounding rock.
6. The modification method according to claim 4, wherein the enlarging and trimming the tunnel to be modified into a predetermined shape includes: And (3) enlarging and excavating the tunnel cave into a structure with a circular cross section by adopting a heading machine, a blasting or a mechanical mode.
7. The improvement as set forth in claim 4 wherein constructing a phase change concrete lining layer on the supported surrounding rock surface comprises: And according to the preset operation conditions of the tunnel cave structure and the performance parameter conditions of the phase-change concrete lining layer, corresponding phase-change concrete materials are selected or prepared for pouring.
8. The improvement according to claim 4, characterized in that said sealing layer is a steel plate layer or a polymer composite layer, and the permeability of said sealing layer material is less than 1 x 10 -20 m 2 .

Description

Roadway tunnel structure for compressed air energy storage and transformation method Technical Field The invention relates to the technical field of energy storage and underground space recycling, in particular to a tunnel cave structure for compressed air energy storage and a transformation method. Background The compressed air energy storage is used as a high-efficiency and extensible large-scale energy storage technology, and is a key means for solving the intermittent problem of renewable energy sources such as wind energy, solar energy and the like. Roadway cave spaces are considered as potential underground compressed air energy storage candidate places due to stable geological structures, huge space capacity and lower development cost. The roadway tunnel compressed air energy storage system has two main problems of roadway tunnel thermal fatigue caused by cold and hot circulation and low energy conversion rate of the system: (1) And the tunnel cave collapses caused by the cold and hot circulation. The essence of compressed air energy storage is the conversion between electric energy and molecular potential energy and heat energy, the stored electric energy or released electric energy every day can lead the temperature of stored gas to be suddenly increased to 140 ℃ or suddenly reduced to-40 ℃, so that the roadway is in a cold and hot circulating environment with different degrees and thermal fatigue damage occurs, the thermal fatigue life of surrounding rock which is closer to the roadway is shorter, the design service life of the roadway compressed air energy storage system is 30-50 years, but the thermal fatigue life of rock materials is generally less than 1 year. (2) The energy conversion rate of the system is low. The nature of compressed air energy storage is conversion between electric energy and molecular potential energy and heat energy, so that the surface turbine needs to be subjected to heat-supplementing power generation when electric energy is released, the volume specific surface area of the tunnel space is larger, the heat exchange loss of an interface in the energy storage process is more obvious, a large amount of natural gas needs to be combusted on the surface to supplement heat for the turbine, and the total life cycle cost of the tunnel compressed air energy storage is 15% -45% higher than that of a salt cavern compressed air energy storage system of the same type, and an enterprise is 'uneconomical'. Therefore, how to modify the tunnel and cave when constructing the compressed air energy storage system of the tunnel and cave, so that the tunnel and cave are prevented from being corroded by thermal fatigue damage, and the energy conversion efficiency of the system is improved, and the technical problem to be solved by the person skilled in the art is urgent. Disclosure of Invention In order to solve the technical problems in the prior art, the invention provides a tunnel structure for storing compressed air and a modification method thereof, so as to improve the mechanical stability and air tightness of the tunnel. In order to achieve the above object, the present invention provides a tunnel structure for storing compressed air, the tunnel structure sequentially comprising, from outside to inside: the surrounding rock body is reinforced by support; the phase-change concrete lining layer is attached to the inner wall of the surrounding rock body, and the sealing layer is paved on the inner surface of the phase-change concrete lining layer; the phase-change concrete lining layer stores and releases heat through a phase-change process, maintains the temperature stability of surrounding rock and supplements heat for gas in the release stage. Preferably, the cross section of the tunnel cave structure is circular, and the radius of the circular shape is not smaller than the maximum loose circle radius of the surrounding rock body. Preferably, the performance parameters and the satisfied conditions of the phase-change concrete lining layer include: Compressive strength of phase-change concrete: ; Wherein, sigma c is the compressive strength of the phase-change concrete, sigma 0 is the stress of the original rock, and sigma g_max is the maximum gas pressure when compressed air stores energy; phase transition temperature of phase transition concrete: ; wherein T 1 is the temperature of the raw rock, Is the phase transition temperature; The heat storage capacity of the phase-change concrete is larger than the heat release capacity of the single compressed air energy storage and inflation stage, and the phase-change enthalpy and construction thickness of the phase-change concrete are as follows: ; Wherein ρL is the phase change enthalpy of the phase change concrete, L is the unit length, A is the inner surface area of the phase change concrete, d is the thickness of the phase change concrete, n 1 is the total air mass under standard atmospheric pressure, n 2 is the total air mass under max