An intensive uranium in-situ leaching well arrangement method
By adopting an intensive uranium leaching drilling layout method, which combines vertical main wells and directional wells, the problems of wide well distribution, large land acquisition area and high construction difficulty have been solved. This method has also enabled the concentration of wellheads and monitoring points, reducing the management cost and construction difficulty of the mining area.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING RESEARCH INSTITUTE OF CHEMICAL ENGINEERING AND METALLURGY
- Filing Date
- 2022-03-02
- Publication Date
- 2026-07-24
AI Technical Summary
Existing in-situ leaching uranium mining processes involve a wide distribution of wells, large land acquisition areas, scattered seepage prevention monitoring points, and a large workload for inspections, especially in complex terrain conditions where construction is difficult.
The intensive in-situ leaching uranium drilling layout method is adopted, which involves constructing one set of vertical main wells and multiple sets of directional wells. The wellheads are centrally located, and the directional wells adopt a five-segment structure. The distance between the wellhead and the edge of the well site is reasonably arranged, and the functional zoning of the wells is clearly defined, so as to achieve the centralization of wellheads, seepage prevention monitoring points and inspections.
It reduced the land acquisition area in the mining area, lowered the construction difficulty and cost, simplified the management process, and enabled the centralized layout of wellheads, seepage prevention monitoring points and inspections, thereby improving the management efficiency of the mining area.
Smart Images
Figure CN116733436B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of sandstone-type uranium leaching mining technology, and in particular to an intensive uranium leaching drilling layout method. Background Technology
[0002] With the continuous expansion of exploration results for sandstone-type uranium deposits, the domestic natural uranium industry layout has gradually shifted from hard rock in the south to sandstone in the north. Currently, the main mining technology for sandstone-type uranium deposits in my country is in-situ leaching, or uranium mining for short. Since breakthroughs were achieved in the 1980s, my country's in-situ leaching uranium mining technology has been practiced and applied in multiple sandstone-type uranium deposits, including the Ili Basin and Turpan-Hami Basin in Xinjiang, and the Erenhot Basin, Songliao Basin, and Ordos Basin in Inner Mongolia.
[0003] In-situ leaching (ISL) uranium mining involves drilling a well into a loose sandstone aquifer containing minerals. The leaching agent reacts chemically with the minerals as it flows through the aquifer, dissolving the uranium in the ore. The uranium-containing solution is then pumped to the surface through pumping wells and processed to obtain uranium products. This process eliminates the need for ore transportation, beneficiation, crushing, and tailings dam construction. Although ore is "mined," a solution containing useful components is "extracted." Overall, ISL uranium mining is simple, does not cause displacement of the ore or surrounding rock, produces no tailings, is environmentally friendly, has low costs, and can achieve an economic uranium grade as low as 0.01%. Multiple processes and stages are managed in a closed loop, making it a mining method with typical circular economy characteristics.
[0004] The in-situ leaching uranium mining process can be divided into two parts: the well site and the leaching solution treatment. The well site includes the drilling layout (well type and spacing design and construction), pumping and injection branch pipes and main pipes, the well site control room and supporting equipment, the solution preparation tank, and the gas station. The current mining depth in in-situ leaching areas generally ranges from 200 to 700 meters. The drilling layout is generally a basic regular well type under vertical drilling mining methods, including row, four-point, five-point, or seven-point well types, with a well spacing of generally 20 to 40 meters. The drilling layout area is generally close to the planar distribution area of sandstone-type uranium deposits. Although the wellhead location occupies a small area, the overall distribution of wells in the mining area is wide, and the pipeline network connecting the pumping and injection wells is spread throughout the entire mining area. During actual production and development, the land acquisition area is relatively large, the seepage prevention points to be monitored are not concentrated, and the workload of worker inspections is large. If complex surface topography is encountered, such as deep ditches, ravines, hillsides, and rivers, drilling construction becomes extremely difficult. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to provide an intensive method for the layout of uranium leaching wells, which centrally arranges wells with different inclination angles, reduces the land area to be acquired in the mining area, and realizes a mode of centralized wellhead layout, centralized anti-seepage monitoring points, centralized inspection and pipeline layout.
[0006] This invention provides a method for intensive in-situ leaching uranium drilling layout, comprising the following steps:
[0007] Step S1: Construct a set of vertical wells as the main vertical wells, which will be used for pumping fluid.
[0008] Step S2: Construct multiple directional wells centered on the main vertical well. Monitor the drilling process of each directional well and conduct anti-collision directional drilling on the surface. On the surface, the wellheads of the directional wells are closely arranged with the wellhead of the main vertical well as the center.
[0009] The directional well is a two-dimensional directional well, which adopts a five-section design, consisting of the first vertical section, the first build-up section, the stabilization section, the second build-up section, and the second vertical section from the wellhead to the tail.
[0010] The first vertical drilling section starts at a depth greater than 100m, and the second vertical drilling section ends 10-30m above the ore layer; the second vertical drilling section has a drilling angle of 90° and passes through the ore layer.
[0011] Adjacent directional well groups have different well functions;
[0012] The target points of each group of directional wells are evenly distributed according to a rule, with the target point of the main vertical well as the center.
[0013] Step S3: A submersible pump is lowered into the main vertical well or directional well used for pumping to lift the leachate from underground to the surface for further processing.
[0014] Preferably, each group of directional wells consists of 6 to 10 directional wells.
[0015] Preferably, the rule is that the first vertical segment of each group of directional well ore layers is arranged in a regular hexagonal, regular quadrilateral, or linear manner with the target point of the vertical segment of the main vertical well ore layer as the center.
[0016] Preferably, the distance between directional well target points in adjacent groups is 30-50m.
[0017] Preferably, the distance between the target point of the main vertical well and the nearest directional well target point is 30-50m.
[0018] Preferably, the wellhead spacing is 2-5m, and the distance between the outermost wellhead and the edge of the well site is 5-10m.
[0019] Preferably, in step S2, five sets of directional wells are constructed with the main vertical well as the center.
[0020] Preferably, the five groups of directional wells arranged outward from the main vertical well are injection wells, pumping wells, injection wells, pumping wells, and injection wells, respectively.
[0021] Compared with existing technologies, the intensive in-situ leaching uranium drilling layout method of the present invention changes the current scattered and vertical drilling layout of in-situ leaching mines. It adopts a centralized "directional well + vertical well" combined drilling method, which on the one hand greatly reduces the land acquisition area and land acquisition costs, and protects the surface environment to the greatest extent. On the other hand, it reduces the amount of pre-drilling engineering, simplifies the surface gathering and transportation process, and realizes the "four-centralized" model of centralized wellhead layout, centralized anti-seepage monitoring points, centralized inspection, and centralized pipeline layout. This facilitates comprehensive mine management, saves later management costs, and is a new development model that conforms to the development trend. Attached Figure Description
[0022] Figure 1 This diagram illustrates the two-dimensional directional wellbore structure of the present invention.
[0023] Figure 2 This diagram illustrates the well network structure in the first embodiment of the present invention.
[0024] Figure 3 This diagram illustrates the wellhead and well site in the first embodiment of the present invention.
[0025] Figure 4 This is a longitudinal cross-sectional view of the well structure along the well layout axis in the first embodiment of the present invention;
[0026] Figure 5 This is a schematic diagram of the well network structure in the second embodiment of the present invention;
[0027] Figure 6 This diagram illustrates the wellhead and well site in the second embodiment of the present invention.
[0028] Figure 7 This is a schematic diagram of the longitudinal cross-section of the well shaft structure along the well layout axis in the second embodiment of the present invention;
[0029] In the picture,
[0030] 1-Wellhead, 2-First vertical well section, 3-First build-up section, 4-Stabilizing section, 5-Second build-up section, 6-Second vertical well section. Detailed Implementation
[0031] To further understand the present invention, embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the present invention.
[0032] This invention is applicable to mineral deposits with a burial depth greater than 400m that are mined using in-situ leaching technology, including but not limited to sandstone-type uranium deposits.
[0033] An embodiment of the present invention discloses an intensive in-situ leaching uranium mining well layout method, comprising the following steps:
[0034] Step S1: Construct a set of vertical wells as the main vertical wells, which will be used for pumping fluid.
[0035] Preferably, each group of directional wells consists of 6 to 10 directional wells;
[0036] Step S2: Construct multiple directional wells centered on the main vertical well. Monitor the drilling process of each directional well and conduct anti-collision directional drilling on the surface. On the surface, the wellheads of the directional wells are closely arranged with the wellhead of the main vertical well as the center.
[0037] The directional well is a two-dimensional directional well, which adopts a five-section design. From the wellhead 1 to the well tail, it consists of the first vertical well section 2, the first build-up section 3, the stabilization section 4, the second build-up section 5, and the second vertical well section 6.
[0038] The first inclined section 3 has a starting point with a vertical depth greater than 100m, and the second inclined section 5 ends 10-30m above the ore layer; the second vertical well section 6 has an angle of 90° and passes through the ore layer.
[0039] Adjacent directional well groups have different functions; specifically, if one group is for injection wells, then the other group is for pumping wells.
[0040] The target points of each group of directional wells are evenly distributed according to a rule, with the target point of the main vertical well as the center.
[0041] The preferred rule is that the first vertical segment of each group of directional well ore layers is arranged in a regular hexagonal, regular quadrilateral, or linear manner with the target point of the vertical segment of the main vertical well ore layer as the center;
[0042] The distance between adjacent directional well target points in different groups is 30~50m;
[0043] The distance between the target point of the main vertical well and the nearest directional well target point is 30~50m;
[0044] The wellhead spacing is 2-5m, and the distance between the outermost wellhead and the edge of the well site is 5-10m.
[0045] Based on the combination of the main vertical well and the directional wells, preferably, five sets of directional wells are constructed with the main vertical well as the center.
[0046] Centered on the main vertical well, the five groups of directional wells arranged outwards are injection wells, pumping wells, injection wells, pumping wells, and injection wells, respectively.
[0047] Step S3: A submersible pump is lowered into the main vertical well or directional well used for pumping to lift the leachate from underground to the surface for further processing.
[0048] To further understand the present invention, the intensive in-situ leaching uranium mining drilling layout method provided by the present invention will be described in detail below with reference to the embodiments. The scope of protection of the present invention is not limited by the following embodiments.
[0049] Example 1
[0050] A vertical well is constructed as the main vertical well, and five groups of directional wells are arranged outward from the main vertical well. Each group consists of six two-dimensional directional wells, and the well body structure adopts a five-section design.
[0051] Target distribution: The target point for the first directional well group is located at the vertex of a regular hexagon centered on the main vertical well target point, with a distance of 30-50m between the main vertical well target point and the first directional well target point. The vertex of a regular hexagon centered on the main vertical well target point, with a radius twice that of the first directional well group, is the target point for the third directional well group. The vertex of a regular hexagon centered on the main vertical well target point, with a radius three times that of the first directional well group, is the target point for the fifth directional well group. The center points of each side of the regular hexagon formed by the third directional well group target points are used as the target points for the second directional well group, and similarly, the center points of each side of the regular hexagon formed by the fifth directional well group target points are used as the target points for the fourth directional well group. The target structure is as follows: Figure 2 As shown.
[0052] Wellhead Distribution: Centered on the main vertical well, six rays are drawn along the direction of the regular hexagon formed by the target points of the first directional well group. These six rays divide the well site area into six uniformly sized sectors. Each ray represents a well layout axis. Directional wells with target points located on the well layout axis and those located in the sector area counterclockwise from that axis are arranged along the axis in ascending order of distance from the target point of the main vertical well. The spacing between wellheads on the same axis is 2-5 meters. For ease of construction, the outermost wellhead is 5-10 meters from the edge of the well site. The wellhead layout structure is as follows: Figure 3 As shown.
[0053] Distribution of pumping and injection functions: The main vertical well is the pumping well, the 1st, 3rd and 5th directional well groups are the injection wells, and the 2nd and 4th directional well groups are the pumping wells.
[0054] Along the well placement axis, the longitudinal profile of the well placement system is as follows: Figure 4 As shown.
[0055] Example 2
[0056] One row of vertical wells is constructed as the main vertical well row, and three rows of directional wells are constructed on each side of the vertical well. Each directional well is a two-dimensional directional well, and the well body structure adopts a five-section design.
[0057] Target distribution: The spacing between targets in each row is the same, 25m, and the spacing between targets in each row of directional wells is the same, 35m. Targets in adjacent rows of directional wells are staggered, meaning that the targets in one row are located on the center line of the line connecting the targets in another row. The target structure is as follows: Figure 5 As shown.
[0058] Fluid pumping / injection function distribution: Each row of wells has the same pumping / injection function, while adjacent rows have opposite functions; that is, one row is for injection wells, and the other row is for pumping wells. The main vertical well row is designated as pumping wells, the adjacent directional well rows on both sides are for injection wells, and further outwards are pumping wells. The function distribution of each well is as follows: Figure 5 As shown.
[0059] Wellhead distribution: The main vertical well row serves as the well layout axis. Pumping wells are arranged closer to the axis, while injection wells are located outside the pumping wells. The spacing between wellheads in each row is 2m, and the spacing between rows is 5m. To facilitate construction, the outermost wellhead is positioned 5-10m from the edge of the well site. The wellhead layout structure is as follows: Figure 6 As shown.
[0060] Along the well placement axis, the longitudinal profile of the well placement system is as follows: Figure 7 As shown.
[0061] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.
[0062] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for intensive in-situ leaching uranium mining well layout, characterized in that, Includes the following steps: Step S1: Construct a set of vertical wells as the main vertical wells, which will be used for pumping fluid. Step S2: Construct multiple directional wells centered on the main vertical well. Monitor the drilling process of each directional well and conduct anti-collision directional drilling on the surface. On the surface, the wellheads of the directional wells are closely arranged with the wellhead of the main vertical well as the center. The directional well is a two-dimensional directional well, which adopts a five-section design, consisting of the first vertical section, the first build-up section, the stabilization section, the second build-up section, and the second vertical section from the wellhead to the tail. The first vertical drilling section starts at a depth greater than 100m, and the second vertical drilling section ends 10m to 30m above the ore layer; the second vertical drilling section has a drilling angle of 90° and passes through the ore layer. Adjacent directional well groups have different functions; if one group is for injection wells, then the other group is for pumping wells. The target points of each group of directional wells are evenly distributed according to a rule, with the target point of the main vertical well as the center; each group of directional wells consists of 6 to 10 directional wells; the distance between the target points of adjacent groups of directional wells is 30m to 50m; the distance between the target point of the main vertical well and the nearest directional well target point is 30m to 50m. Step S3: A submersible pump is lowered into the main vertical well or directional well used for pumping to lift the leachate from underground to the surface for further processing.
2. The intensive in-situ leaching uranium drilling layout method according to claim 1, characterized in that, The rule is that the first vertical well section of each group of directional wells is arranged in a regular hexagonal, regular quadrilateral, or linear manner, with the target point of the vertical section of the main vertical well as the center.
3. The intensive in-situ leaching uranium mining well layout method according to claim 1, characterized in that, The wellhead spacing is 2m to 5m, and the distance between the outermost wellhead and the edge of the well site is 5m to 10m.
4. The intensive in-situ leaching uranium mining well layout method according to claim 1, characterized in that, In step S2, five sets of directional wells are constructed with the main vertical well as the center.
5. The intensive in-situ leaching uranium drilling layout method according to claim 4, characterized in that, Centered on the main vertical well, the five groups of directional wells arranged outwards have the functions of injection wells, pumping wells, injection wells, pumping wells, and injection wells, respectively.