WO2022088387A1 - 松散泥砂岩地质的中深层无干扰地热供热系统、方法 - Google Patents

松散泥砂岩地质的中深层无干扰地热供热系统、方法 Download PDF

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Publication number
WO2022088387A1
WO2022088387A1 PCT/CN2020/133886 CN2020133886W WO2022088387A1 WO 2022088387 A1 WO2022088387 A1 WO 2022088387A1 CN 2020133886 W CN2020133886 W CN 2020133886W WO 2022088387 A1 WO2022088387 A1 WO 2022088387A1
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Prior art keywords
pipe
return pipe
geothermal well
geothermal
water supply
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PCT/CN2020/133886
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English (en)
French (fr)
Inventor
刘洪涛
刘腾
解振涛
刘攀峰
Original Assignee
陕西西咸新区沣西新城能源发展有限公司
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Priority to US17/527,071 priority Critical patent/US11624530B2/en
Publication of WO2022088387A1 publication Critical patent/WO2022088387A1/zh

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D3/00—Hot-water central heating systems
    • F24D3/18—Hot-water central heating systems using heat pumps
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B33/00—Sealing or packing boreholes or wells
    • E21B33/10—Sealing or packing boreholes or wells in the borehole
    • E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/20—Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S20/00—Solar heat collectors specially adapted for particular uses or environments
    • F24S20/40—Solar heat collectors combined with other heat sources, e.g. using electrical heating or heat from ambient air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S70/00—Details of absorbing elements
    • F24S70/20—Details of absorbing elements characterised by absorbing coatings; characterised by surface treatment for increasing absorption
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24T—GEOTHERMAL COLLECTORS; GEOTHERMAL SYSTEMS
    • F24T10/00—Geothermal collectors
    • F24T10/10—Geothermal collectors with circulation of working fluids through underground channels, the working fluids not coming into direct contact with the ground
    • F24T10/13—Geothermal collectors with circulation of working fluids through underground channels, the working fluids not coming into direct contact with the ground using tube assemblies suitable for insertion into boreholes in the ground, e.g. geothermal probes
    • F24T10/17—Geothermal collectors with circulation of working fluids through underground channels, the working fluids not coming into direct contact with the ground using tube assemblies suitable for insertion into boreholes in the ground, e.g. geothermal probes using tubes closed at one end, i.e. return-type tubes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B10/00—Integration of renewable energy sources in buildings
    • Y02B10/40—Geothermal heat-pumps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/10—Geothermal energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/40—Solar thermal energy, e.g. solar towers

Definitions

  • the invention belongs to the technical field of geothermal heating, in particular to a middle-deep non-interference geothermal heating system and method based on loose mud sandstone geology.
  • Geothermal heating system refers to a heating system that uses geothermal energy as the main heat source.
  • Geothermal energy is the energy stored in the earth itself, which belongs to renewable energy.
  • Geothermal heating system can be divided into direct heating according to the way that geothermal fluid enters the heating system.
  • direct heating means that the geothermal fluid is directly introduced into the heating system
  • indirect heating means that the geothermal fluid transfers thermal energy to the circulating water of the heating system through the heat exchanger, and the geothermal fluid does not directly enter the heating system.
  • the existing heat pump design is to first select the compressor according to the heat load and temperature difference, then design the heat exchanger, and then substitute the heat exchanger parameters into the compressor to check, so as to determine the size and model of each heat pump equipment. Match the temperature of the undisturbed geothermal heat source in the middle and deep layers, so that the heat pump unit is inefficient or even unable to start.
  • the loose structure of the geothermal wells has high water content, and the geothermal wells are prone to collapse during drilling construction, and it is easy to cause shallow groundwater interlayers and shallow groundwater pollution, endangering the The safety of drinking water limits the development of geothermal resources to a certain extent.
  • the purpose of the present invention is to provide a middle-deep non-interference geothermal heating system and method based on loose mud sandstone geology, which has the advantages of environmental protection and solves the problem of geothermal wells under the existing non-interference geothermal well formation process under the existing loose mud sandstone geological conditions. It is easy to collapse, and it is easy to cause shallow groundwater cascade and shallow groundwater pollution, which endangers the safety of drinking water.
  • the present invention provides the following technical solutions:
  • the embodiment of the present invention provides a middle-deep undisturbed geothermal heating system based on loose mud sandstone geology, including a return pipe and an inlet pipe, the right side of the return pipe is connected with a second high-area return pipe, the second high The right side of the area return pipe is connected with the first high area return pipe, the left side of the water inlet pipe is connected with a meter, the right side of the water inlet pipe is connected with a high area water supply pipe, and between the return pipe and the water inlet pipe A differential pressure overflow pipe is communicated, the right side of the first high-area return pipe is respectively connected with a first return pipe and a return pipe, and the side of the return pipe away from the first high-area return pipe is connected with a heat pump unit, so The side of the first return pipe away from the first high-area return pipe is connected with a bypass pipe, the bottom of the heat pump unit is connected with a water supply pipe and a second return pipe, and the side of the water supply pipe away from the heat pump
  • the first geothermal well water supply pipe, the side of the second water return pipe away from the heat pump unit is connected with the first geothermal well return pipe, and the side of the first geothermal well return pipe away from the second return pipe is connected with the second geothermal well a water return pipe, the side of the first geothermal well water supply pipe away from the water supply pipe is connected with a second geothermal well water supply pipe, and the second geothermal well return water pipe and the ground well water supply pipe are far away from the first geothermal well return pipe and the first geothermal well
  • One side of the water supply pipe is provided with a geothermal well wellhead device, and the side of the geothermal well wellhead device close to the second geothermal well return pipe and the second geothermal well water supply pipe is communicated with the second geothermal well return pipe and the second geothermal well water supply pipe and the bottom of the wellhead device of the geothermal well communicates with the casing heat exchanger arranged in the geothermal well.
  • the side of the bypass pipe away from the first water return pipe is connected with the water supply pipe of the geothermal well, and the side of the heat pump unit away from the return pipe is connected with the return pipe of the geothermal well.
  • a geothermal well water pump is provided on the outside of the second water return pipe, and the side of the geothermal well water pump close to the second water return pipe is communicated with the second water return pipe.
  • a differential pressure controller is provided on the left side of the differential pressure overflow pipe, and the side of the differential pressure controller close to the differential pressure overflow pipe is communicated with the differential pressure overflow pipe.
  • the side close to the heat pump unit is communicated with the heat pump unit.
  • the casing heat exchanger includes an inner tube and an outer tube, the outer tube is sleeved outside the inner tube, and the inner tube is formed by connecting several sections of PE pipes in sequence, and the first section of the PE pipe is a screen. pipe, and the bottom of the first section of PE pipe is provided with a counterweight pipe.
  • the geothermal well includes an inner well wall tube and an outer well wall tube, the inner well wall tube is connected with the outer well wall tube, and a polyurethane thermal insulation layer is arranged between the inner well wall tube and the outer well wall tube.
  • the outer surface of the inner well wall pipe is provided with a solar heat absorbing coating, and the inner surface of the outer well wall pipe and the inner surface of the inner well wall pipe are both provided with an anti-corrosion coating.
  • the embodiment of the present invention also provides a construction method of a middle-deep non-interference geothermal heating system based on loose mud sandstone geology, the method is:
  • Step 1 Construct a geothermal well with a two-opening structure.
  • the surface is downward.
  • the first-opening structure is within 500m of the shallow layer as the cementing section.
  • the 347 bit is used to drill down, the ⁇ 273 surface casing is run, and the cement slurry is cemented;
  • the two-opening structure is 0 -2500m is drilled with 241 bit, and 177 casings are drilled to 2500m;
  • Step 2 Go down the casing heat exchanger. After the geothermal well with the two-open structure is drilled, immediately run down the outer tube of the casing heat exchanger. In the inner tube of the casing heat exchanger, the first section of PE pipe A solid steel pipe is added to the bottom as a counterweight for caissoning.
  • a drilling fluid with a specific gravity of ⁇ 1.08, a funnel viscosity of ⁇ 35s, and a loss of ⁇ 15ml/30min is injected simultaneously; when drilling in a negative pressure formation, it is easy to collapse. 10 meters before the layer, inject drilling fluid with specific gravity 1.04-1.06, funnel viscosity 30-35s, water loss 6-10ml/min, filtrate viscosity 29-31s, and salinity 1-2%.
  • the present invention provides a return pipe, a differential pressure overflow pipe, a gauge, a water inlet pipe, a differential pressure controller, a high-area return pipe, a first return pipe, a return pipe, a bypass pipe, and a high-area return pipe.
  • Water supply pipe high area return pipe, geothermal well return pipe, geothermal well water supply pipe, heat pump unit, second return pipe, water supply pipe, geothermal well water, geothermal well water supply pipe, geothermal well return pipe, geothermal well return pipe, geothermal well.
  • the use of water supply pipes, geothermal well head devices and geothermal wells solves the problem of undisturbed geothermal well formation technology under the existing loose mud sandstone geological conditions, which is easy to cause shallow groundwater interlayers and shallow groundwater pollution, which endangers the safety of drinking water. question.
  • Fig. 1 is the structural representation of the present invention
  • Fig. 2 is the enlarged view of A in Fig. 1 of the partial structure of the present invention
  • Fig. 3 is the enlarged view of B in Fig. 1 of the partial structure of the present invention.
  • Fig. 4 is the enlarged view of C in Fig. 1 of the partial structure of the present invention.
  • Fig. 5 is the enlarged view of D in Fig. 1 of the partial structure of the present invention.
  • Fig. 6 is the enlarged view of E in Fig. 1 of the partial structure of the present invention.
  • FIG. 7 is an enlarged view of F in FIG. 1 showing a partial structure of the present invention.
  • connection may be a fixed connection, It can also be a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components.
  • connected may be a fixed connection, It can also be a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components.
  • the water return pipe 1, the differential pressure overflow pipe 2, the gauge 3, the water inlet pipe 4, the differential pressure controller 5, the high area return water pipe 6, the first return water pipe 7, the return water pipe 8, the bypass pipe 9, High area water supply pipe 10, high area return water pipe 11, geothermal well return water pipe 12, geothermal well water supply pipe 13, heat pump unit 14, second return water pipe 15, water supply pipe 16, geothermal well water pump 17, first geothermal well water supply pipe 18 , the first geothermal well return pipe 19, the second geothermal well return pipe 20, the second geothermal well water supply pipe 21, the geothermal well wellhead device 22 and the geothermal well 23 and other components are general standard parts or components known to those skilled in the art, Its structure and principles are known to those skilled in the art through technical manuals or through routine experimental methods.
  • a middle-deep undisturbed geothermal heating system based on loose mud sandstone geology including a return pipe 1 and an inlet pipe 4, the right side of the return pipe 1 is connected with the second high-area return pipe 11.
  • the right side of the return pipe 11 in the second high area is connected to the first high area return pipe 6, the left side of the water inlet pipe 4 is connected to the meter 3, the right side of the water inlet pipe 4 is connected to the high area water supply pipe 10, the return pipe 1 and the inlet pipe A differential pressure overflow pipe 2 is communicated between the water pipes 4, and the right side of the first high-area return pipe 6 is connected with a first return pipe 7 and a return pipe 8, respectively, and the return pipe 8 is far away from the first high-area return pipe 6 side
  • the heat pump unit 14 is communicated with, the side of the first return pipe 7 away from the first high area return pipe 6 is connected with a bypass pipe 9, and the bottom of the heat pump unit 14 is respectively connected with a water supply pipe 16 and a second return pipe 15.
  • the water supply pipe 16 The side away from the heat pump unit 14 is connected to the first geothermal well water supply pipe 18, the side of the second return pipe 15 away from the heat pump unit 14 is connected to the first geothermal well return pipe 19, and the first geothermal well return pipe 19 is far from the second return pipe.
  • One side of the water pipe 15 is communicated with a second geothermal well water return pipe 20 , a side of the first geothermal well water supply pipe 18 away from the water supply pipe 16 is connected with a second geothermal well water supply pipe 21 , the second geothermal well return pipe 20 and the second geothermal well
  • the side of the well water supply pipe 21 away from the ground well return pipe 19 and the first geothermal well water supply pipe 18 is provided with a geothermal well wellhead device 22, and the geothermal well wellhead device 22 is close to the second geothermal well return pipe 20 and the second geothermal well water supply pipe 21.
  • One side communicates with the second geothermal well return pipe 20 and the second geothermal well water supply pipe 21 , and the bottom of the geothermal well wellhead device 22 communicates with the casing heat exchanger 24 arranged in the geothermal well 23 .
  • the return pipe 1, the water inlet pipe 4, the first high area return pipe 6, the bypass pipe 9, the high area water supply pipe 10, the second high area return pipe 11, the geothermal well return pipe 12, and the geothermal well water supply pipe 13 communicate with each other.
  • the diameter is DN300.
  • the diameters of the differential pressure overflow pipe 2 and the first water return pipe 7 are DN200.
  • the diameters of the return pipe 8, the second return pipe 15, the water supply pipe 16, the first geothermal well water supply pipe 18, the first geothermal well return pipe 19, the second geothermal well return pipe 20, and the second geothermal well water supply pipe 21 is DN150.
  • the side of the bypass pipe 9 away from the first return pipe 7 is communicated with the geothermal well water supply pipe 13 , and the side of the heat pump unit 14 away from the return pipe 8 is communicated with the geothermal well return pipe 12 .
  • a geothermal well water pump 17 is disposed outside the second water return pipe 15 , and the side of the geothermal well water pump 17 close to the second water return pipe 15 is communicated with the second water return pipe 15 .
  • the left side of the differential pressure overflow pipe 2 is provided with a differential pressure controller 5, the side of the differential pressure controller 5 close to the differential pressure overflow pipe 2 is communicated with the differential pressure overflow pipe 2, and the high area water supply pipe 10 is close to the heat pump unit 14. One side is communicated with the heat pump unit 14 .
  • the heat pump unit 14 By arranging the heat pump unit 14, the heat exchange characteristics of the mid-deep geothermal heat can be matched, and the energy efficiency of the unit can be greatly improved.
  • the heat pump unit 14 When in use, the heat pump unit 14 takes the circulating water of the geothermal well 23 as the heat source, and exports the underground heat energy to supply 45°C hot water to the user’s transmission and distribution system.
  • the secondary side transmission and distribution system is designed according to 45/35°C. Years of operating experience are efficiently matched.
  • the system is equipped with a bypass system. When the temperature of the geothermal well is high in the early stage of heating, the geothermal well 23 will directly supply the user without starting the heat pump unit 14, making full use of the geothermal energy for heating.
  • the heat pump unit 14 When descending to the high-efficiency operating range of the heat pump unit 14, the heat pump unit 14 is started to supply heat to achieve the effect of energy cascade utilization.
  • the middle-deep non-interference geothermal heating system based on loose mud sandstone geology, by setting the return pipe 1, the differential pressure overflow pipe 2, the gauge 3, the water inlet pipe 4, the differential pressure controller 5, the high zone Return pipe 6, first return pipe 7, return pipe 8, bypass pipe 9, high area water supply pipe 10, high area return pipe 11, geothermal well return pipe 12, geothermal well water supply pipe 13, heat pump unit 14, second return pipe Water pipe 15, water supply pipe 16, geothermal well water pump 17, first geothermal well water supply pipe 18, first geothermal well return pipe 19, second geothermal well return pipe 20, second geothermal well water supply pipe 21, geothermal well wellhead device 22 and
  • the use of the geothermal well 23 solves the problem that the existing non-interference geothermal well formation process under the geological conditions of loose mud sandstone easily causes shallow groundwater interlayer and shallow groundwater pollution, which endangers the safety of drinking water.
  • the casing heat exchanger includes an inner pipe and an outer pipe, the outer pipe is sleeved outside the inner pipe, and the inner pipe is formed by connecting several sections of PE pipes in sequence, the first section of the PE pipe is a screen pipe, and the third section of the PE pipe is a screen pipe.
  • a counterweight pipe is arranged at the bottom of a PE pipe.
  • the geothermal well 23 includes an inner well wall tube and an outer well wall tube, the inner well wall tube is connected with the outer well wall tube, and a polyurethane thermal insulation layer is arranged between the inner well wall tube and the outer well wall tube, which can meet the long-term requirements.
  • Time insulation requirements, and the polyurethane material has good wear resistance, aging resistance and adhesion, which can be suitable for the use environment of geothermal wells.
  • the outer surface of the inner well wall tube is provided with a solar energy heat absorbing coating. Since the inner well wall tube directly contacts the water source in the geothermal well, the outer surface of the inner well wall tube has a higher temperature, and the solar heat absorbing coating can better absorb infrared rays. Therefore, a heat accumulating layer is formed on the outer surface of the inner well wall pipe, which reduces the heat overflow of the inner well wall pipe and further improves the thermal insulation effect.
  • Both the inner surface of the outer well wall tube and the inner surface of the inner well wall tube are provided with anti-corrosion coatings.
  • the inner well wall pipe and the outer well wall pipe are made of petroleum casing material.
  • the use of petroleum casing material can improve the strength of the wellbore structure, prevent the wellbore from collapsing, and has good corrosion resistance, which can be applied to the complex water source environment in geothermal wells and prolong the service life of geothermal wells.
  • the embodiment of the present invention provides a construction method of a middle-deep non-interference geothermal heating system based on loose mud sandstone geology, the method is:
  • Step 1 Construction of geothermal well 23 with two-opening structure, the surface is downward, the first-opening structure is within 500m of the shallow layer is the cementing section, the 347 bit is used to drill down, the ⁇ 273 surface casing is run, and the cement slurry is cemented; the two-opening structure 0-2500m is drilled with 241 bit, and 177 casing is drilled to 2500m;
  • a drilling fluid with a specific gravity ⁇ 1.08, a funnel viscosity ⁇ 35s, and a loss of ⁇ 15ml/30min is injected simultaneously; when drilling in a negative pressure formation, enter the easily collapsed layer Before the first 10 meters, inject drilling fluid with a specific gravity of 1.04-1.06, a funnel viscosity of 30-35s, a water loss of 6-10ml/min, a filtrate viscosity of 29-31s, and a salinity of 1-2%.
  • the deep structure of two open wells can effectively separate and block the shallow groundwater layer to prevent the groundwater interlayer pollution.
  • Step 2 Go down the casing heat exchanger. After the geothermal well 23 of the two-open structure is drilled, immediately run down the outer tube of the casing heat exchanger. In the inner tube of the casing heat exchanger, the first section PE A solid steel pipe is added to the bottom of the pipe as a counterweight for caissoning.

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Abstract

一种基于松散泥砂岩地质的中深层无干扰地热供热系统及方法，包括回水管和进水管，回水管的右侧连通有第二高区回水管，第二高区回水管的右侧连通有第一高区回水管。通过设置回水管、差压溢流管、量表、进水管、差压控制器、第一高区回水管、第一回水管、回水管、旁通管、高区供水管、第二高区回水管、地热井回水管、地热井供水管、热泵机组、第二回水管、供水管、地热井供水管、地热井回水管、地热井回水管、地热井供水管、地热井井口装置和地热井的配合使用，解决了现有松散泥砂岩地质条件下的无干扰地热井成井工艺容易造成浅层地下水串层以及浅层地下水污染，危及饮用水安全的问题。

Description

松散泥砂岩地质的中深层无干扰地热供热系统、方法 技术领域
本发明属于地热供热技术领域，具体涉及一种基于松散泥砂岩地质的中深层无干扰地热供热系统及方法。
背景技术
地热供热系统是指利用地热能为主要热源的供热系统，地热能为地球本身蕴藏的能量，属于可再生能源，地热供热系统按照地热流体进入供热系统的方式可分为直接供热和间接供热，直接供热即把地热流体直接引入供热系统，间接供热即地热流体通过换热器将热能传递给供热系统的循环水，地热流体不直接进入供热系统。
现有的热泵设计是根据热负荷及温差先选则压缩机再设计换热器，再用换热器参数代入压缩机校核，从而确定热泵各设备尺寸型号，这样设计得出的热泵机组不能匹配中深层无干扰地热热源温度，从而使得热泵机组效率低甚至无法启动。
在现有松散泥砂岩地质条件下中深层无干扰地热井施工过程中，其结构松散含水性高，钻井施工中容易发生地热井垮塌，且容易造成浅层地下水串层以及浅层地下水污染，危及饮用水安全，在一定程度上限制了地热资源的开发。
发明内容
本发明的目的在于提供一种基于松散泥砂岩地质的中深层无干扰地热供热系统及方法，具备环保的优点，解决了现有松散泥砂岩地质条件下的无干扰地热井成井工艺下地热井易坍塌，易造成浅层地下水串层以及浅层地下水污染，危及饮用水安全的问题。
为实现上述目的，本发明提供如下技术方案：
本发明实施例提供一种基于松散泥砂岩地质的中深层无干扰地热供热系统，包括回水管和进水管，所述回水管的右侧连通有第二高区回水管，所述第 二高区回水管的右侧连通有第一高区回水管，所述进水管的左侧连通有量表，所述进水管的右侧连通有高区供水管，所述回水管和进水管之间连通有差压溢流管，所述第一高区回水管的右侧分别连通有第一回水管和回水管，所述回水管远离第一高区回水管的一侧连通有热泵机组，所述第一回水管远离第一高区回水管的一侧连通有旁通管，所述热泵机组的底部分别连通有供水管和第二回水管，所述供水管远离热泵机组的一侧连通有第一地热井供水管，所述第二回水管远离热泵机组的一侧连通有第一地热井回水管，所述第一地热井回水管远离第二回水管的一侧连通有第二地热井回水管，所述第一地热井供水管远离供水管的一侧连通有第二地热井供水管，所述第二地热井回水管和地井供水管远离第一地热井回水管和第一地热井供水管的一侧设置有地热井井口装置，所述地热井井口装置靠近第二地热井回水管和第二地热井供水管的一侧与第二地热井回水管和第二地热井供水管连通，所述地热井井口装置的底部连通设置在地热井内的套管换热器。
上述方案中，所述旁通管远离第一回水管的一侧连通有地热井供水管，所述热泵机组远离回水管的一侧连通有地热井回水管。
上述方案中，所述第二回水管的外侧设置有地热井水泵，所述地热井水泵靠近第二回水管的一侧与第二回水管连通。
上述方案中，所述差压溢流管的左侧设置有差压控制器，所述差压控制器靠近差压溢流管的一侧与差压溢流管连通，所述高区供水管靠近热泵机组的一侧与热泵机组连通。
上述方案中，所述套管换热器包括内管和外管，所述外管套设在内管的外部，所述内管由若干节PE管依次连接组成，第一节PE管为筛管，并且第一节PE管的底部设置配重管。
上述方案中，所述地热井包括内井壁管和外井壁管，所述内井壁管与外井壁管连接，所述内井壁管和外井壁管之间设置聚氨酯保温层。
上述方案中，所述内井壁管的外表面设置太阳能吸热涂层，所述外井壁管的内表面和内井壁管的内表面均设置有防腐涂层。
本发明实施例还提供一种基于松散泥砂岩地质的中深层无干扰地热供热系统的施工方法，该方法为：
步骤1：施工二开结构的地热井，地表往下，一开结构即浅层500m以内为固井段，采用347钻头下钻，下入φ273表层套管，水泥浆固井；二开结构0-2500m采用241钻头下钻，下入177套管至2500m；
步骤2：套管换热器下井，在二开结构的地热井钻孔完毕后，立即下入套管换热器的外管，在套管换热器的内管中，第一节PE管底部加入实心钢管作为配重进行沉井。
上述方案中，所述步骤1中，在一开地层的钻孔时，同步注入比重≥1.08，漏斗粘度≥35s，漏失量≤15ml/30min的钻井液；在负压地层钻井时，进入易塌层前10米之前，将比重1.04-1.06、漏斗粘度30-35s、失水量6-10ml/min、滤液粘度29-31s、矿化度1-2％的的钻井液注入。
与现有技术相比，本发明通过设置回水管、差压溢流管、量表、进水管、差压控制器、高区回水管、第一回水管、回水管、旁通管、高区供水管、高区回水管、地热井回水管、地热井供水管、热泵机组、第二回水管、供水管、地热井水、地热井供水管、地热井回水管、地热井回水管、地热井供水管、地热井井口装置和地热井的配合使用，解决了现有松散泥砂岩地质条件下的无干扰地热井成井工艺，容易造成浅层地下水串层以及浅层地下水污染，危及饮用水安全的问题。
附图说明
图1为本发明结构示意图；
图2为本发明局部结构的图1中A的放大图；
图3为本发明局部结构的图1中B的放大图；
图4为本发明局部结构的图1中C的放大图；
图5为本发明局部结构的图1中D的放大图；
图6为本发明局部结构的图1中E的放大图；
图7为本发明局部结构的图1中F的放大图。
图中：1回水管、2差压溢流管、3量表、4进水管、5差压控制器、6高区回水管、7第一回水管、8回水管、9旁通管、10高区供水管、11高区回水管、12地热井回水管、13地热井供水管、14热泵机组、15第二回水管、16供水管、17地热井水泵、18地热井供水管、19地热井回水管、20地热井回水管、21地热井供水管、22地热井井口装置、23地热井、24套管换热器。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
在发明的描述中，需要说明的是，术语“上”、“下”、“内”、“外”“前端”、“后端”、“两端”、“一端”、“另一端”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本发明和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本发明的限制。此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性。
在发明的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”、“设置有”、“连接”等，应做广义理解，例如“连接”，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是机械连接，也可以是电连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以具体情况理解上述术语在本发明中的具体含义。
本发明中的回水管1、差压溢流管2、量表3、进水管4、差压控制器5、高区回水管6、第一回水管7、回水管8、旁通管9、高区供水管10、高区回水管11、地热井回水管12、地热井供水管13、热泵机组14、第二回水管15、供水管16、地热井水泵17、第一地热井供水管18、第一地热井回水管19、第二地热井回水管20、第二地热井供水管21、地热井井口装置22和地热井23等 部件均为通用标准件或本领域技术人员知晓的部件，其结构和原理都为本领域技术人员均可通过技术手册得知或通过常规实验方法获知。
请参阅图1-7，一种基于松散泥砂岩地质的中深层无干扰地热供热系统，包括回水管1和进水管4，回水管1的右侧连通有第二高区回水管11，第二高区回水管11的右侧连通有第一高区回水管6，进水管4的左侧连通有量表3，进水管4的右侧连通有高区供水管10，回水管1和进水管4之间连通有差压溢流管2，第一高区回水管6的右侧分别连通有第一回水管7和回水管8，回水管8远离第一高区回水管6的一侧连通有热泵机组14，第一回水管7远离第一高区回水管6的一侧连通有旁通管9，热泵机组14的底部分别连通有供水管16和第二回水管15，供水管16远离热泵机组14的一侧连通有第一地热井供水管18，第二回水管15远离热泵机组14的一侧连通有第一地热井回水管19，第一地热井回水管19远离第二回水管15的一侧连通有第二地热井回水管20，第一地热井供水管18远离供水管16的一侧连通有第二地热井供水管21，第二地热井回水管20和第二地热井供水管21远离地井回水管19和第一地热井供水管18的一侧设置有地热井井口装置22，地热井井口装置22靠近第二地热井回水管20和第二地热井供水管21的一侧与第二地热井回水管20和第二地热井供水管21连通，地热井井口装置22的底部连通设置在地热井23内的套管换热器24。
所述回水管1、进水管4、第一高区回水管6、旁通管9、高区供水管10、第二高区回水管11、地热井回水管12、地热井供水管13的通径为DN300。
所述差压溢流管2、第一回水管7的通径为DN200。
所述回水管8、第二回水管15、供水管16、第一地热井供水管18、第一地热井回水管19、第二地热井回水管20、第二地热井供水管21的通径为DN150.
旁通管9远离第一回水管7的一侧连通有地热井供水管13，热泵机组14远离回水管8的一侧连通有地热井回水管12。
第二回水管15的外侧设置有地热井水泵17，地热井水泵17靠近第二回水管15的一侧与第二回水管15连通。
差压溢流管2的左侧设置有差压控制器5，差压控制器5靠近差压溢流管2的一侧与差压溢流管2连通，高区供水管10靠近热泵机组14的一侧与热泵机组14连通。
通过设置专用材料和结构的套管换热器，可优化提升井下水动力工况，提升换热孔的取热量；
通过设置热泵机组14，能够匹配中深层地热的换热特性大大提高了机组的能效。
使用时，热泵机组14以地热井23循环水为热源，将地下热能导出供给用户输配系统45℃热水，二次侧输配系统按照45/35℃设计，热源侧和热泵机组14根据公司多年运行经验高效匹配，该系统具备旁路系统，在供热初期地热井温度较高时，由地热井23直供用户，不启动热泵机组14，充分利用地热能供热，在地热井23温度下降到热泵机组14高效运行区间时，启动热泵机组14供热，达到能量梯级利用的效果。
综上所述：该基于松散泥砂岩地质的中深层无干扰地热供热系统，通过设置回水管1、差压溢流管2、量表3、进水管4、差压控制器5、高区回水管6、第一回水管7、回水管8、旁通管9、高区供水管10、高区回水管11、地热井回水管12、地热井供水管13、热泵机组14、第二回水管15、供水管16、地热井水泵17、第一地热井供水管18、第一地热井回水管19、第二地热井回水管20、第二地热井供水管21、地热井井口装置22和地热井23的配合使用，解决了现有松散泥砂岩地质条件下的无干扰地热井成井工艺，容易造成浅层地下水串层以及浅层地下水污染，危及饮用水安全的问题。
所述套管换热器包括内管和外管，所述外管套设在内管的外部，所述内管由若干节PE管依次连接组成，第一节PE管为筛管，并且第一节PE管的底部设置配重管。
所述地热井23包括内井壁管和外井壁管，所述内井壁管与外井壁管连接，所述内井壁管和外井壁管之间设置聚氨酯保温层，能够满足长时间的保温需求，而且聚氨酯材料具有良好的耐磨性、耐老化性和粘合性，可以适用于地热井的 使用环境。
所述内井壁管的外表面设置太阳能吸热涂层，由于内井壁管直接接触地热井中的水源，导致其外表面有较高的温度，而太阳能吸热涂层能够较好吸收红外线，从而在内井壁管的外表面形成一个聚热层，降低内井壁管的热量溢出，进一步提高了保温效果。
所述外井壁管的内表面和内井壁管的内表面均设置有防腐涂层。
所述内井壁管、外井壁管均为石油套管材质。采用石油套管材质可以提高井身结构的强度，防止井身坍塌，而且具有较好的耐腐蚀性，可以适用于地热井中复杂的水源环境，延长地热井的使用寿命。
本发明实施例提供一种基于松散泥砂岩地质的中深层无干扰地热供热系统的施工方法，该方法为：
步骤1：施工二开结构的地热井23，地表往下，一开结构即浅层500m以内为固井段，采用347钻头下钻，下入φ273表层套管，水泥浆固井；二开结构0-2500m采用241钻头下钻，下入177套管至2500m；
具体地，所述步骤1中，在一开地层的钻孔时，同步注入比重≥1.08，漏斗粘度≥35s，漏失量≤15ml/30min的钻井液；在负压地层钻井时，进入易塌层前10米之前，将比重1.04-1.06、漏斗粘度30-35s、失水量6-10ml/min、滤液粘度29-31s、矿化度1-2％的的钻井液注入。
采用两开井深结构可有效分隔、封堵浅层地下水层，防止地下水串层污染。
步骤2：套管换热器下井，在二开结构的地热井23钻孔完毕后，立即下入套管换热器的外管，在套管换热器的内管中，第一节PE管底部加入实心钢管作为配重进行沉井。
尽管已经示出和描述了本发明的实施例，对于本领域的普通技术人员而言，可以理解在不脱离本发明的原理和精神的情况下可以对这些实施例进行多种变化、修改、替换和变型，本发明的范围由所附权利要求及其等同物限定。

Claims (9)

  1. 一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：包括回水管和进水管，所述回水管的右侧连通有第二高区回水管，所述第二高区回水管的右侧连通有第一高区回水管，所述进水管的左侧连通有量表，所述进水管的右侧连通有高区供水管，所述回水管和进水管之间连通有差压溢流管，所述第一高区回水管的右侧分别连通有第一回水管和回水管，所述回水管远离第一高区回水管的一侧连通有热泵机组，所述第一回水管远离第一高区回水管的一侧连通有旁通管，所述热泵机组的底部分别连通有供水管和第二回水管，所述供水管远离热泵机组的一侧连通有第一地热井供水管，所述第二回水管远离热泵机组的一侧连通有第一地热井回水管，所述第一地热井回水管远离第二回水管的一侧连通有第二地热井回水管，所述第一地热井供水管远离供水管的一侧连通有第二地热井供水管，所述第二地热井回水管和地井供水管远离第一地热井回水管和第一地热井供水管的一侧设置有地热井井口装置，所述地热井井口装置靠近第二地热井回水管和第二地热井供水管的一侧与第二地热井回水管和第二地热井供水管连通，所述地热井井口装置的底部连通设置在地热井内的套管换热器。
  2. 根据权利要求1所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：所述旁通管远离第一回水管的一侧连通有地热井供水管，所述热泵机组远离回水管的一侧连通有地热井回水管。
  3. 根据权利要求2所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：所述第二回水管的外侧设置有地热井水泵，所述地热井水泵靠近第二回水管的一侧与第二回水管连通。
  4. 根据权利要求3所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：所述差压溢流管的左侧设置有差压控制器，所述差压控制器靠近差压溢流管的一侧与差压溢流管连通，所述高区供水管靠近热泵机组的一侧与热泵机组连通。
  5. 根据权利要求4所述的一种基于松散泥砂岩地质的中深层无干扰地热供 热系统，其特征在于：所述套管换热器包括内管和外管，所述外管套设在内管的外部，所述内管由若干节PE管依次连接组成，第一节PE管为筛管，并且第一节PE管的底部设置配重管。
  6. 根据权利要求5所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：所述地热井包括内井壁管和外井壁管，所述内井壁管与外井壁管连接，所述内井壁管和外井壁管之间设置聚氨酯保温层。
  7. 根据权利要求6所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统，其特征在于：所述内井壁管的外表面设置太阳能吸热涂层，所述外井壁管的内表面和内井壁管的内表面均设置有防腐涂层。
  8. 一种基于松散泥砂岩地质的中深层无干扰地热供热系统的施工方法，其特征在于，该方法为：
    步骤1：施工二开结构的地热井，地表往下，一开结构即浅层500m以内为固井段，采用347钻头下钻，下入φ273表层套管，水泥浆固井；二开结构0-2500m采用241钻头下钻，下入177套管至2500m；
    步骤2：套管换热器下井，在二开结构的地热井钻孔完毕后，立即下入套管换热器的外管，在套管换热器的内管中，第一节PE管底部加入实心钢管作为配重进行沉井。
  9. 根据权利要求8所述的一种基于松散泥砂岩地质的中深层无干扰地热供热系统的施工方法，其特征在于，所述步骤1中，在一开地层的钻孔时，同步注入比重≥1.08，漏斗粘度≥35s，漏失量≤15ml/30min的钻井液；在负压地层钻井时，进入易塌层前10米之前，将比重1.04-1.06、漏斗粘度30-35s、失水量6-10ml/min、滤液粘度29-31s、矿化度1-2％的的钻井液注入。
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