阅读说明：本技术 中深层地热能采集同井抽回系统 (Medium-deep geothermal energy collection same-well pumping-back system ) 是由 冯卫红 于 2019-09-18 设计创作，主要内容包括：本发明公开了一种中深层地热能采集同井抽回系统,包括采集井和换热组件；采集井包括井体,井体包括下部的热能提取区和上部的回灌区,在热能提取区与回灌区之间的相邻处设有封闭装置,在封闭装置的中心设有用于穿过抽水管的通孔,抽水管的下端延伸至热能提取区内,在抽水管的下端连接有用于抽取地热水的潜水泵；在回灌区的井管外侧与井孔内壁之间填充有石英砂滤料层；换热组件包括过滤净化装置和换热器。本发明采用具有抽水和回水功能的采集井,采集利用中深层地热水中的热量,但不消耗地热水,换热后的地热水回灌率高,不会造成地下水位的降低,不会造成地质结构的改变和破坏。本发明占地面积小,便于施工和维护,成本更低,资源利用率更高。(The invention discloses a middle-deep geothermal energy collection same-well pumping system, which comprises a collection well and a heat exchange assembly, wherein the collection well is connected with the heat exchange assembly; the collecting well comprises a well body, the well body comprises a heat energy extraction area at the lower part and a recharge area at the upper part, a sealing device is arranged at the adjacent position between the heat energy extraction area and the recharge area, a through hole for penetrating through a water pumping pipe is arranged at the center of the sealing device, the lower end of the water pumping pipe extends into the heat energy extraction area, and a submersible pump for pumping geothermal water is connected to the lower end of the water pumping pipe; a quartz sand filter material layer is filled between the outer side of a well pipe and the inner wall of a well hole in the reinjection area; the heat exchange assembly comprises a filtering and purifying device and a heat exchanger. The invention adopts the collecting well with the functions of pumping water and returning water to collect and utilize the heat in the geothermal water of the middle-deep layer, but does not consume geothermal water, and the geothermal water after heat exchange has high recharging rate, thus not causing the reduction of the underground water level and the change and the damage of the geological structure. The invention has small floor area, convenient construction and maintenance, lower cost and higher resource utilization rate.)

1. the system is characterized by comprising a collecting well and a heat exchange assembly;

The collecting well comprises a well body, the well body comprises a heat energy extraction area at the lower part and a recharge area at the upper part, the diameter of a well hole of the heat energy extraction area is smaller than that of a well hole of the recharge area, a sealing device is arranged at the adjacent position between the heat energy extraction area and the recharge area, the sealing device comprises a bearing steel plate and a sealing rubber plate fixedly arranged on the lower surface of the bearing steel plate, and the sealing device is arranged at the top of the well hole of the heat energy extraction area; a through hole for penetrating through a water pumping pipe is formed in the center of the bearing steel plate, the lower end of the water pumping pipe extends into the heat energy extraction area, and a submersible pump for pumping geothermal water is connected to the lower end of the water pumping pipe; a quartz sand filter material layer is filled between the outer side of a well pipe of the reinjection area and the inner wall of a well hole;

the heat exchange assembly comprises a filtering and purifying device and a heat exchanger, the water pumping pipe is communicated with the water inlet pipe of the filtering and purifying device, the water outlet pipe of the filtering and purifying device is communicated with the water inlet of the heat exchanger, the heat exchanger is connected into a heating pipe network, the water outlet of the heat exchanger is connected with a water return pipe, the water outlet end of the water return pipe extends to the interior of the recharge area, and geothermal water after heat exchange flows back to the recharge area through the water return pipe.

2. The system for collecting geothermal energy in the middle deep layer of claim 1 and pumping back the geothermal energy in the same well, wherein the filtering and purifying device comprises a tank body with an opening at the top, a water inlet pipe and a water outlet pipe, and a frosted filter material layer, a quartz sand filter material layer and a PVC water-spraying packing layer are sequentially arranged in the tank body from bottom to top; uniformly distributed air inlet holes are formed in the side wall of the tank body in the area corresponding to the PVC water-spraying packing layer, and an oxygen adding fan for exhausting air upwards is arranged at the opening at the top of the tank body; a water retaining groove is arranged at the position of the side wall of the tank body, which covers the air inlet hole area;

The water inlet pipe extends to the inside of the tank body and is positioned above the PVC water spraying packing layer, a plurality of water outlet pipe heads are uniformly distributed on the part of the water inlet pipe positioned in the tank body, and a water inlet valve is arranged on the water inlet pipe; the water outlet is formed in the bottom of the tank body and is connected with a water outlet pipe, and a water outlet valve is arranged on the water outlet pipe.

3. The system for collecting geothermal energy from a medium depth layer through the same well as recited in claim 2, wherein the filtration and purification device further comprises a back-flushing pipe, one end of the back-flushing pipe is connected with the water inlet pipe, the connection point is located in front of the water inlet valve, the other end of the back-flushing pipe is connected with the water outlet at the bottom of the tank body, and a flushing valve is arranged on the back-flushing pipe and is used for enabling back-flushing water to enter the tank body from the water outlet at the bottom; a water outlet is formed in the side wall of the tank body between the PVC water-spraying filler layer and the quartz sand filter material layer, the water outlet is connected with a water discharge pipe, and a water discharge valve is arranged on the water discharge pipe and used for discharging back washing water; the drain pipe is communicated to an external sedimentation tank.

4. The system of claim 2, wherein the bottom of the water retaining groove is annular and connected to the outer wall of the tank, and the side of the water retaining groove surrounds the circumference of the side wall of the tank and has a height greater than the height of the air inlet hole; and a backflow hole is formed in the side wall of the tank body and is close to the bottom of the inner side of the water retaining groove.

5. The system of claim 2, wherein the PVC water-spraying packing layer is composed of a plurality of PVC water-spraying sheets arranged in parallel in the vertical direction, and the PVC water-spraying sheets are in S-wave shape.

6. The system for collecting geothermal energy from a middle deep layer of claim 2, wherein a filler baffle is arranged at the bottom of the frosted filter layer, and water permeable holes are distributed on the filler baffle; the filler baffle is provided with a water permeable groove which protrudes upwards and has a downward opening, and water permeable holes are uniformly distributed on the side wall and the top surface of the water permeable groove.

7. The system of claim 1, wherein the sealing rubber plate is fastened to the load-bearing steel plate by fixing bolts.

8. The system for collecting and withdrawing geothermal energy from the same well in the middle-deep layer according to claim 1, wherein the quartz sand filter material layer is filled with a quartz sand filter material with a diameter of 2-4 mm.

9. The mid-depth geothermal energy harvesting same well pumpback system of claim 1, wherein the depth of the body of the harvesting well is greater than 1000 meters; the recharge area is located at a position between 100 and 500 meters.

10. the system of claim 1, wherein the well casing of the recharge area is a bridge strainer.

Technical Field

The invention relates to the technical field of geothermal energy collection, in particular to a middle-deep layer geothermal energy collection same-well pumping-back system.

Background

In recent years, the problem of air pollution in China is increasingly severe, the regional air environment problem taking inhalable particles (PM 10) and fine particles (PM 2.5) as characteristic pollutants is particularly prominent, and meanwhile, along with the deep promotion of industrialization and urbanization in China, the energy resource consumption is continuously increased, and the pressure for preventing and controlling the air pollution is continuously increased.

The method for heating rooms or commercial occasions by utilizing the heat energy of the underground water source is a clean energy heating mode, is widely applied in recent years, and has some problems in the energy acquisition system of the existing water source heat pump central air conditioner: 1. the method generally adopts a one-pumping multi-return mode collection well, and has the defects that the underground water level is reduced due to incomplete recharging after long-term use, sand removal is generated during use, and adverse effects such as geological collapse and the like are easily caused after long-term use; 2. a buried pipe soil heat exchanger system is generally adopted, and the defects of large occupied area and high cost are overcome; 3. generally, shallow geothermal energy is used as a heat source, the extracted heat is 15-18 ℃, the heat source conversion rate is not high, and the heating effect is not ideal.

Disclosure of Invention

the invention aims to solve the technical problem of providing a middle-deep geothermal energy collecting same-well pumping-back system, which adopts a collecting well with pumping and water-returning functions, pumps geothermal water for heat exchange to provide heat for a heating pipe network, and the geothermal water after heat exchange flows back into the collecting well, so that the system has the advantages of good heat supply effect, high recharging rate, no damage to a geological structure, energy conservation and environmental protection.

In order to solve the technical problems, the invention adopts the following technical scheme:

Designing a middle-deep geothermal energy collection same-well pumping system, which comprises a collection well and a heat exchange assembly;

The collecting well comprises a well body, the well body comprises a heat energy extraction area at the lower part and a recharge area at the upper part, the diameter of a well hole of the heat energy extraction area is smaller than that of a well hole of the recharge area, a sealing device is arranged at the adjacent position between the heat energy extraction area and the recharge area, the sealing device comprises a bearing steel plate and a sealing rubber plate fixedly arranged on the lower surface of the bearing steel plate, and the sealing device is arranged at the top of the well hole of the heat energy extraction area; a through hole for penetrating through a water pumping pipe is formed in the center of the bearing steel plate, the lower end of the water pumping pipe extends into the heat energy extraction area, and a submersible pump for pumping geothermal water is connected to the lower end of the water pumping pipe; a quartz sand filter material layer is filled between the outer side of a well pipe of the reinjection area and the inner wall of a well hole;

The heat exchange assembly comprises a filtering and purifying device and a heat exchanger, the water pumping pipe is communicated with the water inlet pipe of the filtering and purifying device, the water outlet pipe of the filtering and purifying device is communicated with the water inlet of the heat exchanger, the heat exchanger is connected into a heating pipe network, the water outlet of the heat exchanger is connected with a water return pipe, the water outlet end of the water return pipe extends to the interior of the recharge area, and geothermal water after heat exchange flows back to the recharge area through the water return pipe.

According to the technical scheme, the interior of a well body of one collection well is divided into a heat energy extraction area at the lower part and a recharge area at the upper part, geothermal water in a middle-deep layer is extracted from the heat energy extraction area, the extracted geothermal water flows out through a water pumping pipe and is filtered by a filtering and purifying device, then heat exchange is carried out through a heat exchanger (such as a plate heat exchanger), the heat exchanger is connected into a heating pipe network to provide heat for the heating pipe network, the geothermal water after heat exchange flows back to the recharge area through a closed water return pipeline, a quartz sand filter material is filled between a well pipe and the inner wall of a well hole in the recharge area, and the functions of water filtration and heat storage are achieved, so that the recharge geothermal water is subjected to heat exchange with underground water and. A sealing device is arranged between the heat energy extraction area and the recharge area to effectively separate the heat energy extraction area from the recharge area, geothermal water in the recharge area cannot enter the heat energy extraction area, and the influence of recharge water on the water quality and the water temperature of the heat energy extraction area can be avoided; the geothermal water that extracts can filter through filtering purification device earlier before carrying out the heat transfer, can avoid the mineral substance that deep aquatic contains to pollute shallow layer water such as manganese, iron, sulphur, plays the effect of protection indirect heating equipment and pipeline simultaneously.

Preferably, the filtering and purifying device comprises a tank body with an opening at the top, a water inlet pipe and a water outlet pipe, and a frosted filter material layer, a quartz sand filter material layer and a PVC water pouring filler layer are sequentially arranged in the tank body from bottom to top; uniformly distributed air inlet holes are formed in the side wall of the tank body in the area corresponding to the PVC water-spraying packing layer, and an oxygen adding fan for exhausting air upwards is arranged at the opening at the top of the tank body; a water retaining groove is arranged at the position of the side wall of the tank body, which covers the air inlet hole area;

The water inlet pipe extends to the inside of the tank body and is positioned above the PVC water spraying packing layer, a plurality of water outlet pipe heads are uniformly distributed on the part of the water inlet pipe positioned in the tank body, and a water inlet valve is arranged on the water inlet pipe; the water outlet is formed in the bottom of the tank body and is connected with a water outlet pipe, and a water outlet valve is arranged on the water outlet pipe.

After the middle-deep groundwater is pumped up, the groundwater enters the filtering and purifying device through the water inlet pipe, and flows in from the upper part of the tank body, the water inlet pipe adopts a plurality of water outlet pipe heads to realize shunting, and a plurality of pipe heads simultaneously discharge water and disperse water flow, so that the water flow is fully contacted with the PVC water spraying packing layer, and preliminary filtration is realized. Water flows downwards along gaps of the PVC water spraying filler, and meanwhile, under the action of the upper oxygen adding fan, outside air enters the PVC water spraying filler layer part in the tank body through the air inlet hole and is then pumped out by the upper fan, oxygen in the air and the water flow are fully contacted to play an oxidation role, and minerals in geothermal water are more easily filtered subsequently under the oxidation role. The water flowing downwards passes through the quartz sand filter material layer and the frosted filter material layer in sequence to realize further filtration, and the filtered water flows to subsequent heat exchange equipment through the lower water outlet pipe. When rivers pass through PVC trickle filler layer part, some water probably spatters jar external portion through the inlet port, through set up the manger plate groove on jar external wall, can avoid this partial rivers to jar external portion influence other equipment, also avoids wasting water resources, and the manger plate groove can be collected the water of spill and flow back to jar internal again.

Preferably, the filtering and purifying device further comprises a back washing pipe, one end of the back washing pipe is connected with the water inlet pipe, the connection position of the back washing pipe is located in front of the water inlet valve, the other end of the back washing pipe is connected with the water outlet at the bottom of the tank body, and a washing valve is arranged on the back washing pipe and used for enabling back washing water to enter the tank body from the water outlet at the bottom; a water outlet is formed in the side wall of the tank body between the PVC water-spraying filler layer and the quartz sand filter material layer, the water outlet is connected with a water discharge pipe, and a water discharge valve is arranged on the water discharge pipe and used for discharging back washing water; the drain pipe is communicated to an external sedimentation tank.

The tank body can be periodically back-flushed, at the moment, a water source enters through a water outlet at the lower part, flows in the tank body from bottom to top, and carries out back flushing on the frosting filter material layer and the quartz sand filter material layer, wherein impurities flow upwards along with water flow and are discharged to an external sedimentation tank through a water discharge pipe, and after sedimentation, subsequent treatment and discharge are carried out.

Preferably, the bottom surface of the water retaining groove is annular and is connected with the outer wall of the tank body, and the side surface of the water retaining groove surrounds the circumference of the side wall of the tank body and is higher than the air inlet hole area; and a backflow hole is formed in the side wall of the tank body and is close to the bottom of the inner side of the water retaining groove.

The water collected in the water retaining groove can flow back to the tank body through the air inlet, and a backflow hole with a larger aperture can be arranged to prevent the air inlet of the air inlet from being influenced or prevent the water from flowing smoothly due to the smaller aperture of the air inlet, so that the water in the water retaining groove can flow back to the tank body smoothly.

Preferably, the PVC water sprinkling packing layer is composed of a plurality of vertical PVC water sprinkling sheets which are arranged in parallel, and the PVC water sprinkling sheets are in an S-wave shape.

Preferably, a filler baffle is arranged at the bottom of the frosting filter material layer, and water permeable holes are distributed in the filler baffle; the filler baffle is provided with a water permeable groove which protrudes upwards and has a downward opening, and water permeable holes are uniformly distributed on the side wall and the top surface of the water permeable groove.

preferably, the sealing rubber plate is fastened with the bearing steel plate through a fixing bolt.

preferably, the quartz sand filter material layer is formed by filling a quartz sand filter material with the diameter of 2-4 mm.

Preferably, the depth of the well body of the collecting well is more than 1000 meters; the recharge area is located at a position between 100 and 500 meters.

Preferably, the well pipe of the recharge area is a bridge type strainer.

Preferably, the diameter of the well bore of the recharge area is 600mm, and the diameter of the well pipe of the recharge area is 300 mm.

Preferably, the diameter of a well hole of a region with the depth of 500-1000 meters in the heat energy extraction zone is 300mm, the well pipe is a spiral pipe with the thickness of 250mm, and water is not taken from the region; the water taking area is located in an area with the depth of more than 1000 meters, the diameter of a well hole is 250mm, water is taken from cracks of the bedrock, and a well pipe does not need to be placed.

The invention has the beneficial effects that:

1. the invention relates to a clean energy heating mode for heating rooms or commercial occasions by using underground middle-deep layer heat energy as energy, which is mainly used for collecting geothermal water heat in strata below 800 meters and heating buildings. The collecting well can return water while extracting heat, only collects energy in the underground water of a middle-deep layer, does not consume the underground water, extracts the geothermal water and returns to the well after heat exchange of an external heat exchange device, the recharge rate is close to 100 percent, and the collecting well does not have high temperature and high pressure in operation and does not have sand deposition in long-term operation.

2. the system is characterized in that the system is connected with a purifying and filtering device in series through pipelines, mineral substances such as manganese, iron, sulfur and the like contained in deep water can be filtered, the filtering and purifying device adopts an integrated design and a structure of sequential multiple filtration, a PVC water spraying packing layer is adopted for preliminary filtration, a plurality of water outlet pipe heads disperse water flow, the contact range of the water flow and the PVC water spraying packing layer is enlarged, the water flow is fully contacted with outside air while flowing through the PVC water spraying packing layer through an oxygen adding motor and an air inlet, an oxidation effect is achieved, the mineral substances in the water flow are oxidized, and subsequent further filtration is facilitated. The water splashed out of the air inlet hole area can be collected by arranging the water retaining groove and flows back into the tank body; the back washing of the filtering device can be realized by arranging a back washing pipe. This filtration purification device is compact reasonable, and is small, takes up an area of fewly, the on-the-spot installation of being convenient for, and operation safe and reliable can effectively filter the deep groundwater of centering, avoids aquatic impurity to damage indirect heating equipment and pipeline, pollutes groundwater when avoiding the backward flow simultaneously, and cooperation deep geothermal water gathers and heating system result of use is better.

3. The invention has high heat utilization rate and good heat supply effect, does not damage the underground geological structure and does not pollute the underground geological structure, and the filtering purification device filters the underground geological structure and then carries out heat exchange and recharging to avoid polluting shallow water and simultaneously plays a role in protecting the heat exchange device and the pipeline.

4. The system of the invention has less land occupation, is convenient for construction, installation and maintenance, the position of the collecting well can be arranged beside a road, in a green belt and the like, only one standard well cover is seen in the appearance, and compared with the existing geothermal collecting mode adopting the heat exchange of the soil of the buried pipe, the system can save a large amount of land occupation area and construction cost.

Drawings

FIG. 1 is a schematic diagram of a deep geothermal energy harvesting same well pumpback system of the present invention;

FIG. 2 is a schematic view of the closure device;

FIG. 3 is a schematic view of the structure of the filtration purification apparatus;

FIG. 4 is a schematic top view of a water retaining tank portion of the filtration purification apparatus;

Fig. 5 is a schematic view showing the development of the air inlet hole portion in the filtration purification apparatus.

Reference numbers in the figures: 1, a heat energy extraction area, 2 a recharge area, 3 a sealing device, 4 a bearing steel plate, 5 a sealing rubber plate, 6 a water pumping pipe, 7 a submersible pump, 8 a water return pipe, 9 a quartz sand filter material layer and 10 a fixing bolt; 11 tank bodies, 12 water inlet pipes, 13 water outlet pipes, 14 frosting filter material layers, 15 quartz sand filter material layers and 16PVC water spraying filler layers; 17 air inlet holes, 18 oxygenation fans; 19 water retaining groove; 20 water outlet pipe heads, 21 backwashing pipes, 22 water discharge pipes, 23 sedimentation tanks, 24 backflow holes, 25 filler baffles and 26 water permeable grooves; 27 bedrock, 28 heat exchangers, 29 filtration and purification devices.

f1 water inlet valve, F2 flushing valve, F3 water outlet valve and F4 water outlet valve.

In fig. 3: arrow A is the water inlet flow direction, arrow B is the back washing water flow direction, and arrow C is the air flow direction driven by the oxygenation fan.

The arrows in fig. 1 indicate the direction of water flow.

Detailed Description

The following examples are given to illustrate specific embodiments of the present invention, but are not intended to limit the scope of the present invention in any way. The apparatus elements referred to in the following examples are, unless otherwise specified, conventional apparatus elements; the industrial raw materials are all conventional industrial raw materials which are sold on the market, if not specifically mentioned.