CN101092873B

CN101092873B - Fluctuant dissolving dipping mining method

Info

Publication number: CN101092873B
Application number: CN2007100528192A
Authority: CN
Inventors: 魏宁; 李小春
Original assignee: Wuhan Institute of Rock and Soil Mechanics of CAS
Current assignee: Wuhan Institute of Rock and Soil Mechanics of CAS
Priority date: 2007-07-24
Filing date: 2007-07-24
Publication date: 2012-07-04
Anticipated expiration: 2027-07-24
Also published as: CN101092873A

Abstract

This invention discloses a wave dipping mining method including the following steps: 1, mixing a liquid containing a dissolving solvent and gas to form high-pressure shrinkage gas-liquid mixed fluid to be injected into seam via an injection well, 2, fluctuating the pressure of the seam continuously by rising and reducing pressure of the injection well and a collection well, 3, collecting solvent liquid with minerals from the injection well or the collection well, 4, repeating the above steps till the mineral concentration got from dissolving is lower than economic exploitation.

Description

Fluctuant dissolving dipping mining method

Technical field

The present invention relates to a kind of mining codes, relate in particular to a kind of fluctuant dissolving dipping mining method, be widely used in the production by dissolving and leaching process field of mineral such as uranium, copper, gold, rare earth, zinc based on miscible (mixing) characteristic of gas-liquid and pressure oscillation.

Background technology

Traditional in-situ leaching mining codes are to apply certain constant pressure at the injection well to inject leachant; Leachant generates leaching solution with some mineral generation physics, chemical reaction in ore bed; And in producing well, directly extract leaching solution, obtain valuable mineral through leaching solution.Recovery ratio is the important indicator of solution mining with the speed of gathering, and is to weigh the index that improves resource utilization, also is an important evidence weighing the production by dissolving and leaching process situation.The relative position that injects well and producing well directly has influence on the molten scope and the molten intensity of soaking of soaking of leachant, and the distributing position difference of drilling well causes the different molten scopes of soaking to soak intensity with dissolving; Geotechnical body is a material heterogeneous simultaneously, because cutting rock such as crack, solution cavity form various rock mass heterogeneous and sillar, has caused the advantage flow region and the advantage flow channel of various kinds.The leachant that conventional method is injected mainly directly gets into producing well through advantage flow region and advantage flow channel.Leachant influences being limited in scope of ore bed, and the relatively little permeable areas in the ore bed, leachant flows slowly or does not flow, and forms " dissolve and soak the dead band " or " dead angle ".

Like Fig. 1 (the production fluid flow schematic diagram under the mobility status that has superiority); Under the situation of flow channel that has superiority; Dissolve and soak fluid mainly along flowing in crack (6), solution cavity advantage flow surfaces such as (8) or the flow channel; And leachant can't fully flow with advantage flow surface (passage) ore bed (7) on every side, mineral are obtained in contact, reaction, thereby ore body that should the zone can't fully be gathered.

Like Fig. 2 (at the production fluid flow schematic diagram that has under the hypotonic regional situation), having under the hypotonic regional situation, leachant mainly oozes zone (5) through height and flows, and does not seldom perhaps have leachant and flows through hypotonic zone (4).

Fig. 1,2 shows that the molten scope (influence basin) of soaking of conventional in-situ leaching exploitation method is very limited, has reduced scope and the recovery ratio of mineral reserve and the speed of gathering of mineral production by dissolving and leaching process.

In sum, traditional in-situ leaching mining has following shortcoming:

1. dissolve and soak the relative position that influence basin injected well and producing well and influence, dissolve the scope of soaking and soak the influence that intensity can receive drill holes, the molten dead angle of soaking is arranged with dissolving;

2. because the heterogeneity of ore bed rock soil medium character and variability cause the leachant advantage to flow, the production by dissolving and leaching process process is limited to the influence of ore bed;

3. the production by dissolving and leaching process in hypotonic zone mainly relies on molecular diffusion rather than convection current, disperse to accomplish the production by dissolving and leaching process process, and therefore the exploitation rate in hypotonic zone is slow, influence the recovery ratio of mineral reserve and the speed of gathering.

How to improve the scope of soaking of dissolving? How to solve because the molten difficulty of soaking that the heterogeneity of ore bed causes? How to improve recovery ratio, the recovering range of production by dissolving and leaching process and the speed of gathering? All are the problems that need emphasis to solve.

Summary of the invention

The object of the invention just is to overcome the problems referred to above and the deficiency that prior art exists; Enlarge the scope of application of prior art; A kind of fluctuant dissolving dipping mining method based on ore bed pressure oscillation and gas-liquid mixture high compression or high swell-shrink characteristics is provided; Be a kind of simple, effective, and can exploit the method for accomplishing simultaneously, help improving the recovery ratio of mineral, the speed of gathering and recovering range with conventional in-situ leaching.

The objective of the invention is to realize like this:

The in-situ leaching mining codes have become a kind of production by dissolving and leaching process field that has been widely used in mineral reserve such as uranium, copper, gold, rare earth, zinc, thorium through the development of over half a century.The present invention is the improvement to the in-situ leaching mining codes, and the place is arranged as shown in Figure 3, comprises the following steps:

1. perhaps inject well (1) in hydrometallurgy factory (9), the liquids and gases that comprise leachant mix the gas-liquid mixture fluid that forms high-compressibility and inject ore bed (3) through injecting well (1);

2. constantly fluctuate fluid pressure in the ore bed (3) is promptly through constantly raising or reducing the fluctuation variation that the pressure that injects well (1) and producing well (2) is realized the ore bed mixed-fluid pressure;

3. collect the leaching solution that contains mineral reserve at injection well (1) or producing well (2);

4. repeat above step 1. 2. 3., soak till the mineral reserve concentration of obtaining is lower than the economic exploitation concentration up to dissolving.

Operating principle of the present invention:

Certain pressure forms miscible (or mixing) fluid of leachant and gas down; Increase the breathing character of fluid; Form the high-compressibility fluid-mixing; Fluid-mixing is injected ore bed (3) through injection well (1), constantly reduce and improve the pressure of injection well (1) or producing well (2) then, cause the pressure of the fluid-mixing of ore bed (3) constantly to change fluctuation; Form the swollen compression deformation of fluid-mixing; Make fluid-mixing constantly between the different permeability zones of heterogeneous body ore bed with the flowing of mobile advantage face and non-advantage flow region, increase the mobile time and the chance of leaching solution of hypotonic and non-advantage flow region, then at injection well (1) or producing well (2) is arbitrary or both obtain leaching solution.

The present invention has advantage and good effect:

1. reduce the influence of injection well (1) and producing well (2) well spacing position to recovery ratio and recovering range; Reduce to dissolve and soak the dead angle.

2. weaken because of the non-homogeneous zone of ore bed (height oozes, crack, cave, fingering are serious etc.) causes the advantage of fluid to flow, increase flowing velocity, flow mechanism meeting and the time of leaching solution at hypotonic zone and non-advantage flow region; It is that main solute migration process is that convection current and disperse are main transition process with the molecular diffusion that step-down blends the mobile perimeter zone of advantage, quickens whole production by dissolving and leaching process process, weakens the advantage flow phenomenon to dissolving the negative effect of soaking.

3. under the dynamic pressure effect; Hydraulic gradient in sandstone or the rock mass is dynamic change; Each pressure oscillation all can produce disturbance to the water of hydration on rock particles surface, reduces the retardation of weak water of hydration fluid flow and leach chemistry reaction, accelerates flow process and chemical reaction velocity.

The present invention is applicable to the production by dissolving and leaching process field of mineral such as uranium, copper, gold, rare earth.This method is applicable to any ore bed that can carry out the in-situ leaching exploitation; Also be applicable to the ore bed that is not suitable for carrying out traditional production by dissolving and leaching process method exploitation owing to the ore bed heterogeneity strongly; Be primarily aimed at the latter, the scope and the recovery ratio that improves mineral of big quantum jump tradition production by dissolving and leaching process method.

Description of drawings

Fig. 1 is the production fluid flow schematic diagram under the mobility status that has superiority;

Fig. 2 is at the production fluid flow schematic diagram that has under the hypotonic regional situation;

Fig. 3 is a work sketch map of the present invention;

Fig. 4 is the flow schematic diagram of process medium fluid at ore bed that boost;

Fig. 5 is the flow schematic diagram of step-down process medium fluid at ore bed;

Fig. 6 is that the flow schematic diagram of process medium fluid in advantage flows ore bed pressed in ascending, descending;

Fig. 7 is an injection well pressure variation relation sketch map in time.

Wherein:

1-injection well;

2-producing well;

3-ore bed;

4-hypotonic zone;

5-height oozes the zone;

6-fissure-plane;

7-exploitation dead band;

8-solution cavity (or molten chamber);

9-hydrometallurgy factory (leachant and leaching solution treatment plant).

The specific embodiment

Below in conjunction with accompanying drawing and embodiment the present invention is further specified:

1, about preparation:

Through some existing treatment measures (as: methods such as vacuum method, aeration, gas displacement) the part moisture in the ore bed (3) is discharged formation unsaturation rock mass (not being liquid entirely in the rock mass hole), get into hypotonic zone so that comprise the high compression fluid-mixing of leachant.

2,1. about step:

The liquids and gases that will comprise leachant through liquid gas mixed method (like spray-on process, bubble method etc.) mix in hydrometallurgy factory (9) or injection well (1), mix the fluid-mixing that forms high-compressibility; Gas componant is for being inertia or the little gas (as: gases such as oxygen, nitrogen, carbon dioxide, hydrogen, methane, ammonia) of reaction influence to chemical reaction in molten the soaking, and the volume of gas is in 0.01～1000 times of scope of leaching solution volume; Different ratios can obtain different constrictive fluid-mixings;

Through gas-liquid mixture fluid (comprise leachant) warp injection well (1) the injection ore bed (3) of high pressure injection device (like pump, forcing press, high-pressure bottle etc.) with high-compressibility.

3,2. about step:

Constantly reduce or increase the pressure that injects well (1) and producing well (2) through high pressure injection device (like water pump, high-pressure pump etc.) and realize that the mixed-fluid pressure fluctuation of ore bed (3) changes, its core purpose constantly expands and shrinkage strain in ore bed for the fluid-mixing of realizing high-compressibility.Its pressure oscillation variation changes in time can be any relation, as among Fig. 7 being wherein a kind of variation relation.

* in the process of boosting, miscible (mixing) fluid contraction is oozed zone (5) through height and flowed into hypotonic zone (4), and is as shown in Figure 4.

* in the step-down process, fluid expands in hypotonic zone (4), and flows out hypotonic zone (4), gets into height and oozes zone (5), and is as shown in Figure 5.

* the fluid-flow mode under the situation of the flow surface that has superiority (passage) is as shown in Figure 6; Miscible (mixing) fluid is constantly back and forth exchange between the fissure-plane (6) of the exploitation dead band (7) of non-advantage flow region and advantage flow surface or passage, solution cavity (8), changed the limitation that the conventional method leachant can not arrive non-advantage flow region.

4,3. about step

Collect the leaching solution that contains mineral reserve at injection well (1) or producing well (2); The practical implementation method is for generally obtaining the method for underground fluid, and form is varied: can be employed in injection well (1) and producing well (2) and utilize high-pressure pump to extract the ore bed fluid; Also can adopt fluid in fluid displacement such as the leachant displacement ore bed to obtain to contain after the fluctuation exploitation ore bed fluid of mineral; Also can utilize the high-compressibility (high-expansion) of ore bed fluid to flow out automatically through discharging the pressure that injects well and producing well; Perhaps in the pressure oscillation process, obtain (also can 2. carry out simultaneously) with step.

Claims

1. a fluctuant dissolving dipping mining method is characterized in that comprising the following steps:

4. repeat above step 1. 2. 3., soak till the mineral reserve concentration of obtaining is lower than the economic exploitation concentration up to dissolving;

Said step is 1.:

The liquids and gases that will comprise leachant through liquid gas mixed method mix the fluid-mixing that forms high-compressibility in hydrometallurgy factory (9) or injection well (1); Gas componant is for being inertia or the little gas of reaction influence to chemical reaction in molten the soaking, and the volume of gas is in 0.01～1000 times of scope of leaching solution volume;

Through the high pressure injection device gas-liquid mixture fluid of high-compressibility is injected ore bed (3) through injecting well (1);

Said step is 2.:

Constantly reduce or increase the pressure that injects well (1) and producing well (2) through the high pressure injection device and realize that the mixed-fluid pressure fluctuation of ore bed (3) changes;

This method is applicable to any ore bed that can carry out the in-situ leaching exploitation;

Mixed-fluid pressure fluctuation constantly reducing or increase the pressure realization ore bed (3) that injects well (1) and producing well (2) changes, and realizes fluid-mixing constantly expansion and shrinkage strain in ore bed of high-compressibility;

In the process of boosting, miscible or fluid-mixing shrinks, and oozes the zone through height and flows into hypotonic zone; In the step-down process, fluid expands in hypotonic zone, and flows out hypotonic zone, gets into height and oozes the zone; In the pressure lifting cyclic process, make fluid-mixing constantly between the different permeability zones of heterogeneous body ore bed with the flowing of mobile advantage face and non-advantage flow region, increase the mobile time and the chance of leaching solution of hypotonic and non-advantage flow region.