CN115584957B

CN115584957B - Method for mining salt lake mineral products in segmented and progressive linkage mode

Info

Publication number: CN115584957B
Application number: CN202211417584.3A
Authority: CN
Inventors: 吴蝉
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-11-14
Filing date: 2022-11-14
Publication date: 2024-05-31
Anticipated expiration: 2042-11-14
Also published as: CN115584957A

Abstract

A method for mining salt lake mineral products in a segmented and progressive linkage mode comprises dividing regions into blocks, establishing regional brine seepage fields, peripheral brine recovery and water supplementing, and progressive linkage mining. The method utilizes the original salinized landform and geological structure of the salt lake mining area to divide the mining area, segments the mining body in blocks and mines the mining body one by one, realizes the fine mining of the salt lake mineral product, and is beneficial to the further improvement and improvement of the technical specification and standard of the salt lake mining; by block segmentation arrangement of salt lake mineral products, progressive linkage exploitation and zoned wheel-driven exploitation are adopted, and meanwhile, exploitation of raw salt lake brine, driving exploitation of brine in a residual salt mineral layer and leaching exploitation of solid potassium mineral (substances) in the salt mineral layer are realized; through drainage, driving and leaching tertiary recovery and zonal repeated rotary recovery, the total recovery amount of raw brine ore in a salt deposit can be more than 95%, the leaching recovery rate of solid potassium ore (substance) can be more than 60%, the available resource amount of salt lake potassium, lithium and the like is improved, and the waste of salt lake resources is avoided.

Description

Method for mining salt lake mineral products in segmented and progressive linkage mode

Technical Field

The invention relates to the technical field of mining, in particular to a method for mining salt lake mineral products in a segmented and progressive linkage manner, which is particularly suitable for application of liquid lithium, potassium, boron and other mineral products and symbiotic solid potassium salt ores.

Background

Salt lake minerals include solid soluble salt minerals, liquid brine minerals, which are typically deposited as a layer intergrowth.

The solid soluble salt ore is mainly a mixed deposit ore layer of rock salt, potassium salt and magnesium salt, and the deposit ore layer of the rock salt is mainly composed of rock salt self-shaped crystals with the particle size of 0.5-5 mm, generally contains 1-25% of silt, and is loose, semi-loose or cemented. The deposit mineral layer of potassium salt and magnesium salt is mainly in the form of thin layer, lens or star-like distribution in the rock salt layer, so that the soluble salt mineral product of potassium, also called solid potassium mineral, has no separate exploitation value at present, and is usually converted into liquid brine mineral exploitation. The mineral layer is deposited by stone salt, the thickness is from < 10cm to > 5m, and the mineral layer is frequently deposited alternately with clay, silt and silt layers with different thicknesses and containing salt.

Liquid brine ore is also called brine ore, is called inter-crystalline brine distributed in a rock salt deposit mineral layer, is called pore brine distributed in silt and sand layers, and forms surface water body called lake surface brine. Liquid brine ores can be classified into diving type (also called as immersed brine) and pressure-bearing type (also called as pressure-bearing brine) according to occurrence states, and hydraulic connection between the two is weak. Lake surface brine is usually in close hydraulic connection with diving brine, and the water quantity and water quality are affected by seasonal supply of surface water, and the change is large. The water level burial depth of the brine is 0.2-1 m, the bottom boundary is generally less than 50m, and the brine is an aquifer with a plurality of layers of discontinuously distributed salt-containing clay, silt thin layers or lens bodies. The pressure-bearing brine is sealed and stored underground, the upper covered water-resisting layer is a silt clay layer with the thickness more than 0.2m, the thickness of a single-layer brine-containing salt layer is different from 10cm to more than 5m, the water-resisting layer and the brine-containing salt layer are deposited in a multi-layer superposition mode, the salt grain size, the density, the water content and the pressure of brine pressure bearing are different, the bottom boundary is generally more than 20m and less than 400m, and the initial water level of the water-containing layer is a positive water level. The brine ore is rich in ions such as sodium, potassium, magnesium, lithium, boron, chlorine, sulfate radical and the like, and is a main object of mining of salt lake minerals.

The brine resource amount of brine ore is divided into porosity and water supply degree. Porosity refers to the amount of brine contained in various pores, fissures, and holes in a unit halogen-containing mineral layer. The water supply degree refers to the amount of brine exuded from the salt layer by gravity and natural hydrodynamic force in a unit of the halogen-containing mineral layer. Porosity and water cut are generally considered as the amount of brine that can be produced, i.e., the amount of resources that can be produced. According to the measurement of the porosity and the water supply degree of the halogen-containing salt layer, the water supply degree brine amount of the halogen-containing salt layer is generally less than 60% of the porosity brine amount, in theory, about 30-50% of brine ore cannot flow out of pores by gravity and under the natural hydrodynamic force condition and is remained in the salt ore layer, and the supersaturated brine is added with the actions of crystallization under the strong evaporation and disturbance environment, the effect of mixing different brines, and the like, so that the brine is remained in the salt layer or the clastic layer, and part or all of the crystallization is converted into solid or is sealed in the gaps. After the brine is crystallized, the brine is dispersed in a stone salt layer or a clastic layer, and relative microelements such as lithium, potassium, boron and the like in the brine can not meet the corresponding grade requirements according to the solid mineral evaluation indexes, so that the retained brine mineral can not be mined, and the recoverable amount of the brine mineral is reduced greatly.

The scarcity of salt lake mineral products such as potassium, lithium and the like in China requires the adoption of refined exploitation and utilization of salt lake resources. There are no relevant specifications and standards in terms of exploitation of salt lake resources.

At present, lake surface brine is mined by directly extracting brine, a ditch digging engineering and a pit engineering are mainly adopted for the immersed brine with the burial depth less than 20m and the bearing brine, a well mining engineering is mainly adopted for the brine with the burial depth more than 20m, and the brine is extracted after flowing out by gravity and collecting the brine. The mining method can only mine the reserve of water supply, and the retained porosity brine in the salt deposit layer, because the brine is dispersed in the stone deposit layer or the clastic layer after crystallization, the lithium, potassium, boron and other relative microelements can not meet the grade requirement of the mineral products according to the evaluation index of the solid mineral products, thereby the retained brine mineral products can not be mined, in practice, the recoverable amount of the brine mineral is greatly reduced, and the recoverable amount of resources is greatly reduced because the retained brine mineral accounts for more than 40% of the total amount of the salt lake brine mineral.

The foregoing background description is for the purpose of fully explaining the technical problem underlying the present invention and is specifically stated herein that the technical content described in the background of the present invention by the applicant is not an admission of the prior art and is not a part of the prior art, wherein the technical content is also one of the protection matters disclosed in the present invention.

Disclosure of Invention

The invention aims to improve the recovery rate of brine ore, and simultaneously carries out leaching exploitation on solid potassium ore (matters) to realize solid-liquid mineral integrated exploitation. The invention provides a method for mining salt lake mineral products in a segmented and progressive linkage manner, and aims to effectively improve the yield and efficiency of mining salt lake mineral resources.

The invention adopts the technical scheme that: a method for mining salt lake mineral products in a block-segmented and progressive linkage manner comprises the following steps:

S1, dividing areas into block segments:

according to the natural sedimentary landform and geologic structure characteristics of the salt lake mining area and the geological investigation result, relatively independent mining areas are divided for mining according to the sedimentary concave land and the salt lake sedimentary law which are naturally distributed;

According to geological and hydrogeological characteristics of salt mine deposition in the mining area, dividing a salt mine layer with large deposition thickness and deep burial depth into a central mining area, and dividing a plurality of peripheral mining areas at the periphery of the central mining area;

In the partitioned mining areas, a brine collecting well and a brine collecting channel are distributed along the trend of a brine layer, the brine collecting well is distributed in a central mining area as a main part, the brine collecting channel is used as an auxiliary part to form a brine collecting well line, the whole brine layer is uncovered to a bottom plate, the brine collecting channel is distributed in a peripheral mining area as a main part, the brine collecting well is used as an auxiliary part to form a brine collecting channel system, and a covering layer, a brine-containing salt layer and a water-proof interlayer in the depth of the brine collecting channel are uncovered;

The brine production well line and the brine production canal system divide a salt mine layer into a plurality of block sections with different shapes, and each block section is used as a production unit;

the brine production well line and the brine production canal system are used as a water supplementing channel in the earlier brine production and later brine production, so that brine production-water supplementing engineering combining the brine production well line and the brine production canal system is formed; according to the mining planning requirement, the water supplementing mode is sequentially and orderly developed from the peripheral mining area to the central mining area;

S2, establishing a regional brine seepage field: in the exploitation process, along with the exploitation of brine in a central exploitation area, the water level of the brine is reduced to form a water level dropping funnel, so that a hydrodynamic field for converging the brine in the brine-containing salt layer from the peripheral exploitation area to the central exploitation area is established;

S3, peripheral brine collection and water supplementing: after the dropping funnel is formed, brine is collected in the side part of the dropping funnel and the peripheral mining area, a brine water level pit is formed locally, and water is supplemented by introducing water supplement to the water level pit, so that the block section or a plurality of block sections form a certain water surface and serve as a continuous water supplementing water source to raise the water level and increase the hydraulic gradient of the funnel, and the brine in the brine-containing salt mining layer is promoted to flow to the central area of the funnel;

S4, progressive linkage exploitation: adopting a tertiary exploitation mode to conduct exploitation of brine, adopting drainage exploitation for primary exploitation of brine to form a full-area brine water level dropping funnel, and converging brine in an exploitation area to the center of the funnel; the secondary brine is mined by adopting water supplementing-brine driving, the water head pressure is increased along with the introduction of the water supplementing, and brine in a salt deposit and retained brine are driven to flow to the center of a dropping funnel; the third brine recovery adopts the dissolution filtration type exploitation of the water-replenishing soluble mineral, and the water-replenishing flows from the periphery of the brine dropping funnel to the center, so that the solid soluble salt mineral is dissolved and filtered in a dynamic mode of continuous seepage in the salt mineral layer; and the continuous brine production and water supplementing linkage production of the central mining area and the peripheral mining area are formed, so that the progressive production of the full mining area from the periphery to the center block by block is realized.

Further, in step S1, the brine production-water replenishing process includes laying brine production wells, brine production channels, brine delivery channels and corresponding brine extraction, brine delivery, water replenishing, power supply, pre-evaporation concentration salt fields and other auxiliary facilities in each brine production area, so as to form a brine production-brine replenishing-brine-flooding-ore dissolution integrated mining system consisting of brine production well lines, brine production channels, brine delivery channels and auxiliary facilities.

Further, in the step S4, the mining step is to form a brine water level dropping funnel in the central mining area, and then perform brine mining and water supplementing in the peripheral mining area; the water supplementing principle of the supplementing water is that the side block sections of the mining area are continuously conducted from the side block sections to the center block section step by step; in order to adequately ensure percolation time, percolation mining requires wheel mining at multiple peripheral mining areas.

Further, in step S3, after the content of potassium, lithium, etc. in the brine is reduced by continuously replenishing the makeup water, the brine is subjected to pre-evaporation concentration by a solar salt field to meet the production requirement.

Preferably, the makeup water is prepared from salt field waste sodium salt, potash fertilizer production tailings, tail liquid, surface salt crust and the like and salt lake peripheral river water.

Preferably, the mining area needs to monitor the average potassium ion content of the water replenishing block section in mining, and when the average potassium ion content of the brine is more than 2g/l, normal brine is mined; when the average potassium ion content of the brine is less than 2g/l, the exploitation of the block is stopped.

Further, the central mining area may be on one side of the overall production area, and the peripheral mining areas may be fanned or otherwise differently distributed.

Preferably, the bottom boundary burial depth of the salt deposit layer is more than 20m, the thickness is more than 0.5m, the mode of laying the brine collecting well is mainly adopted, the mode of the brine collecting channel is adopted as an auxiliary mode, and the brine collecting well must be penetrated through all the salt deposit layer and the halogen-containing water layer; the diameter of the brine production well hole is 500-1500mm, the well depth is 3-6m below the bottom plate of the aquifer, and the brine production well hole is used as a salt particle sediment settling section; selectively discharging a water filtering pipe or a bare hole according to hydrogeology requirements according to different stratum structure and different clastic interlayers, and discharging a hole protecting pipe at a wellhead; the deep well submerged pump is used for pumping brine from the position 1-5m away from the bottom boundary of the aquifer, when the thickness of the aquifer is large and the burial depth of the bottom boundary is more than 50m, the pump can be lowered to the position 2/3 of the well depth or is selected to be below a stable water level according to the brine pumping strength, and the position of the lower pump is adjusted along with the lowering of the water level.

Preferably, the bottom boundary burial depth of the salt deposit layer is less than 20m, the thickness is more than 0.5m, the brine collecting channel is mainly used as an auxiliary brine collecting well, and the brine collecting channel must be deep into or dig through the mineral deposit layer and the halogen-containing water layer; the depth of the brine collecting channel is less than 20m, and the width of the channel bottom is 1-3m; the length of the brine collecting channel is the same as the connecting line length of the brine collecting well, and brine collecting pump stations are erected at one end or two ends or suitable positions of the brine collecting channel.

Preferably, in the dissolving-filtering type exploitation, the exploitation mode of multi-zone rotary exploitation is implemented, so that the exploitation synchronization is ensured, one exploitation area stops exploitation, and other exploitation areas continue to normally exploit the halogen, and the rotary exploitation interval period is more than 12 months/round.

The implementation of the invention has the beneficial effects that: the invention relates to a mining system and a mining method for mineral products of a fourth-period salt lake, wherein 33 modern salt lakes are distributed in a Qida basin, which is a concentrated distribution area of the salt lakes in China. The invention combines the original landform of the salt lake mining area, the structural characteristics of the salt mine layer and the geological investigation result, realizes and promotes the exploitation and utilization of the salt lake mineral product, and is beneficial to the further improvement and improvement of the technical specification and standard of the salt lake exploitation; by arranging the salt lake mineral products in a block section mode, progressive linkage mining is adopted, and regional wheel mining is carried out, so that brine in a salt mineral layer is efficiently driven to a mining area in the water supplementing process, the defect that the brine cannot be mined due to the fact that the brine is dispersed in a stone salt layer or a chip layer after crystallization is avoided, and meanwhile, the solid potassium mineral (object) is subjected to leaching mining. By adopting the method, the total extraction amount of the raw brine ore can be more than 95 percent, the leaching recovery rate of the solid potassium ore (substance) can be more than 60 percent through repeated cyclic exploitation, and the waste of salt lake resources is avoided to a great extent.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1: a planar schematic diagram of partition block layout of the brine mining engineering;

fig. 2: and a sectional view of partition block layout of the brine production engineering.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the summary, the meanings of technical names used therein are explained as follows, in order to facilitate understanding by those skilled in the art:

development unit: each original sedimentary pit or geological survey area;

mining area: central mining area + peripheral mining area;

Central mining area: the natural concave underground middle ore layer is thick, the ore body distribution area with deep burial is mainly provided with a brine collecting well and an auxiliary brine collecting channel;

peripheral mining area: the periphery of the central mining area aims at the shallow mining body buried in the mining layer, and the central mining area takes a brine mining channel as a main and a brine mining well as an auxiliary layout area;

Mining block section: mining land blocks segmented by projects such as brine production well lines, brine production channels and the like;

Halogen-water collection system: engineering combination of a brine production well line group and a brine production canal group with the dual functions of brine production and water supplement;

mining-water replenishing unit: the brine-water supplementing system comprises a block section distribution range.

Embodiments of the present invention include the following principles and mining methods, referring to fig. 1 and 2, in fig. 1, a central mining area and a peripheral mining area are divided according to a salt deposit center or thickness, mainly to ensure that sufficient brine is produced, and whether the location is located in the center of the mining area is not necessarily associated with the center of the mining area, the central mining area may be located on one side of the entire mining area, and the peripheral mining area may be distributed in a fan shape or other different manners. In fig. 2, after the brine collecting channel at the edge of each peripheral mining area collects brine, the water level of the brine collecting layer at the edge of the brine collecting layer and the brine collecting channels at the two sides of the brine collecting channel is reduced, brine 'water level depression' (see the edge of a sectional view) is shown, and when the water level reaches the bottom of the canal, water is added for supplementing water. When the potassium ion content in the brine extracted from the block section is less than 2g/l, the brine extraction engineering is used as a water supplementing channel, and the process is advanced to the next block section for brine extraction. When the potassium ion content is less than 2g/l or the water level is recovered slowly and halogen cannot be extracted in the peripheral mining area, the peripheral mining area pauses for halogen extraction, wheel rest is carried out, and halogen extraction is continued in other peripheral mining areas and the central mining area, so that the periodic wheel-type mining of each peripheral area is ensured, and the continuous mining of the whole area is ensured.

According to the natural distribution of the sedimentary pit and the sedimentary law of the salt lakes, the sedimentary pit in the salt lake mining area can be divided, and by means of the geological survey results, the geological survey area can be divided, namely, natural units in the form of the sedimentary pit or the geological survey area can be divided. The sedimentary pit or geological survey partition is divided into a plurality of blocks with different shapes by arranging a brine production well group and a brine production canal system. In the divided mining area, the well and canal combined engineering is laid to uncover the covering layer and the water-proof interlayer of the halogen-containing salt ore layer as the channel for early halogen production and later water supplement.

The salt and the clastic mineral layers of each unit are deposited, are horizontally or horizontally-like distributed from the ground surface to the bottom plate, are clamped by a plurality of salt-containing clastic layers, have large deposition thickness of the salt in the center of deposition, have thick water-containing layer, are buried deeply, gradually thin, branch or pinch towards the periphery, and become gradually shallow. Each natural unit may be used for mining as a relatively independent mining area. The salt deposit ore body with the accumulated thickness more than 0.5m containing brine layer group is regarded as the thickness which can be mined, the solid potassium ore and the potassium ore in the salt ore layer are regarded as the potassium which can be filtered, the ore layer with the burial depth of 0 to 10m at the top boundary of the ore body is mainly provided with a brine-mining well for brine mining, the ore layer with the burial depth of 0 to less than 10m at the top boundary of the ore body is mainly provided with a brine-mining channel for brine mining in a canal-mining mode.

Typically, a central area of deposition of natural cells is selected as the central mining area and a peripheral area is selected as the peripheral mining area around which a plurality of peripheral mining areas may be divided. The central mining area usually has large thickness of a mining layer and deep burial, and is mainly provided with a well mining mode and assisted with a canal mining mode, and brine mining well groups and brine mining canal system combinations are arranged in a concentrated mode. The peripheral mining area usually has small thickness of the mining layer and shallow burial, and mainly adopts canal mining and auxiliary well mining. Because the thickness of the salt layer and the depth of burial are changed on the plane, when the thickness of the mineral layer in the mineral area is changed greatly in the longitudinal direction, the transverse direction and the depth of burial, according to the water level depth of burial and the thickness of the mineral layer, the well mining and the canal mining are distributed alternately, and under special geological conditions, all the areas can be well mining areas or canal mining areas.

The brine mining wells and brine mining channels in the mining area are linearly distributed according to the trend of the ore body to form a plurality of mining engineering combinations such as well line, canal and the like, the range surrounded by each brine mining engineering extension line forms a mining block section, and the mining block section divided by the plurality of brine mining engineering combinations forms a mining block system of the full mining area.

After the brine production engineering of the central mining area continuously produces brine until the water level drops, the mining area forms a brine water level dropping funnel which takes the central mining area as the center and expands outwards, the hydraulic gradient of the brine in the stratum from the periphery to the center is artificially established, and a hydraulic field in which the brine is converged from the periphery of the mining area to the center is formed.

After the mining area dropping funnel is formed, the brine at the edge of the peripheral mining area is mined, and a water level pit is formed at the outer edge of the dropping funnel, so that the water level is reduced, and the hydraulic gradient and the hydraulic pressure are reduced. When the brine production engineering can not continuously produce brine, the brine production engineering can be converted into a water supplementing channel, the prepared mineral solution is used as water supplementing water, water is supplemented to a 'water level concave' area, the water level at the edge of a funnel is improved, the hydraulic gradient and the hydraulic pressure are increased and maintained, the retained brine in a salt layer is extruded, the dynamic balance of brine production and water supplementing is maintained to always face the brine production end of a central mining area, and the retained brine in the salt layer is ensured to flow to the brine production end of the central mining area by the water supplementing.

The water is used to filter the solid potassium (salt) mineral continuously while the water is permeated in the salt mine layer, and the solid potassium (salt) mineral is transported to the center of the funnel together. When the content of potassium ions in brine in the block section is less than 2g/l, the block section pauses mining, water supplementing continues, a high water head is continuously maintained, the water supplementing continues to capture residual brine and solid potassium minerals in the block section, and water supplementing mining is carried out on the adjacent block section, so that the stability of a dropping funnel of a full-mining area is maintained, brine is continuously moved from a peripheral mining area to a central mining area, and full-area linkage brine mining is ensured. According to the condition of brine water level drop in the ore layer, the water supplementing exploitation can be a single segment or a plurality of segments simultaneously, and the water supplementing exploitation is sequentially carried out until the fully exploited area.

The water for supplementing can be prepared by injecting waste sodium salt Tian Rongjie stone salt into the peripheral river and lake water of salt lake, dissolving production tailings (mainly comprising stone salt), preparing surface salt crust and the like, and selecting various modes according to the utilization conditions and the convenience of water supplementing.

According to the distribution of water level dropping funnels in the ore layer, a plurality of peripheral mining areas can be divided in different peripheral directions around the central mining area, so that a plurality of brine-water collecting and supplementing systems of the central mining area and the peripheral mining areas are formed, and each system can serve as a relatively independent mining-water supplementing unit. Because the mining intensity is larger than the flow rate of brine in the stratum and the speed of water supplementing to drive brine and dissolve the mine, a mining mode of wheel-driven mining in a peripheral mining area is required, and the brine driving and dissolving time is ensured. Through repeated wheel-driven mining, salt lake brine ore and solid potassium ore (substances) can be fully mined.

The mining area is matched with mining engineering and public engineering such as construction of brine collecting, brine conveying, water supplementing, power transmission, turnover of salt fields, preparation of water supplementing and the like at the same time of construction of brine collecting engineering.

The mining of each block of mining area is mainly developed by adopting a brine production well and a brine production canal.

The bottom boundary burial depth of the mineral bearing layer is more than 20m, the thickness is more than 0.5m, the well mining mode is mainly used, the canal mining mode is auxiliary, and the brine mining well must be penetrated through all the mineral bearing layer and the halogen bearing water layer. The diameter of the brine-producing well hole is 500-1500mm, the depth of the well reaches 3-6m below the bottom plate of the aquifer, and the brine-producing well hole is used as a salt particle sediment settling section. According to different stratum structure and chip interlayer, selectively lowering the water filtering pipe or the bare hole according to hydrogeology requirement, and protecting the hole pipe under the wellhead.

The deep well submerged pump is used for pumping brine from 1-5m away from the bottom boundary of the aquifer after well formation, when the thickness of the aquifer is large and the burial depth of the bottom boundary is more than 50m, the pump can be lowered to the position of 2/3 of the well depth or is selected to be below a stable water level according to the brine pumping strength, and the position of the pump is adjusted along with the lowering of the water level. The brine production wells are distributed along the trend of the mineral bearing layer to form brine production well line groups, the well spacing is 50 m-300 m, the line spacing is 100 m-500 m, and the length and the width of a well mining area are determined by salt deposition and brine layer group burial depth and plane spreading. When the distribution area of the area in the natural unit of the salt lake is large, after the well production lines are continuously distributed, a large-area well production area is formed, and the water level burial depth of the bottom boundary of the water-bearing layer is less than 20m and is the well production boundary.

The bottom boundary of the ore-bearing layer has a burial depth of less than 20m and a thickness of more than 0.5m, the main part is the canal mining, the auxiliary part is the well mining, and the brine mining canal must be deep into or dig through the ore-bearing layer and the halogen-bearing water layer. The depth of the brine collecting channel is less than 20m, the width of the channel bottom is 1-3m, the width of the channel opening is different due to different slope stability of a salt mine layer, the brine collecting channel is generally more than 20m, the channel spacing is 100 m-less than 500m, and the length of the brine collecting channel is the same as the connecting line length of the brine collecting well. And selecting one end or two ends or suitable parts of the canal to erect a brine-collecting pump station, and selecting a mixed flow pump to carry out brine-collecting according to the water quantity.

The width of a single block section in the mining area is less than 500m, the depth is the depth of a seam bottom boundary or a mining engineering, and partial salt ores below the mining engineering depth are driven by edge water supplement and bottom pasting or by brine mining wells. The length of the mining block section is equivalent to that of the brine-producing well line and the brine-producing channel, and the mining block section covers the full-mining area.

The mine with a plurality of sedimentary pockets or geological survey areas is characterized in that each sedimentary pocket and each geological survey area are relatively independent development units, and orderly exploitation can be carried out according to mine development planning.

Aiming at a mining area where salt lake brine and solid mineral products coexist, according to the characteristics of liquid as a main material and interconversion of solid and liquid mineral products, three modes of drainage, driving and dissolving filtration are adopted for mining, and the mining is adopted as a technical scheme for mining of each independent development unit.

And (5) draining and mining. Selecting a region with large thickness and stable distribution of a salt layer and a water-bearing layer in a central mining area, constructing a brine-mining well and canal group, mining after each well and canal mining line is built, and continuously pumping brine. Through continuous brine mining, brine positions in each block section of the central mining area are lowered to form a dropping funnel, and the dropping funnel is deepened and enlarged gradually. The center of the brine dropping funnel and the periphery form a hydraulic gradient. Continuously extracting brine, continuously enlarging and deepening a brine dropping funnel, continuously enlarging the hydraulic gradient, enlarging the flow pressure of brine in a halogen-containing water layer to the center of the dropping funnel, and promoting the brine to flow to a brine collecting end, thereby artificially establishing a hydrodynamic field for underground brine to flow from the periphery of the funnel to the center, and ensuring that brine in each section moves to the center of the funnel. The exploitation of the brine at this stage is the lyophobic exploitation, the structure of the halogenous water stratum is different, the amount of the exploited brine is different, and the exploited brine can generally reach 40-50% of the total amount of the original brine in the halogenous water mineral layer.

Driving the mining. After the bittern water level of the central mining area is generally reduced to a position more than 1/3 below the original water level, the periphery of the dropping funnel of the peripheral mining area is parallel or vertical to the central mining area, and a bittern collecting canal and well group are arranged until the zero boundary of the mining layer. And (5) superposing halogen collection on the water level surface at the edge of the dropping funnel. By continuous brine extraction, a "water level depression" zone is formed on the dropping funnel. When the water level of the brine collecting channel and the brine collecting well is generally reduced or reaches the bottom of the brine collecting channel and the bottom of the brine collecting well, the brine collecting channel and the brine collecting well serve as water supplementing channels, supplementing water is introduced, a water head is increased, the pressure of brine in a brine-containing water layer is increased, and brine in a salt-retaining layer and non-extracted brine in a block section are driven to move towards a brine collecting end in the center of a funnel. The exploitation of the brine at this stage is driven exploitation, and generally, the exploitation can be carried out by 20-30% of the total amount of the raw brine in the halogen-containing water mineral layer.

And (5) leaching and mining. When the average content of potassium ions in brine adopted in the block section is less than 2g/l, the block section is stopped from collecting brine, the supplementing water is continuously introduced into a brine collecting channel or a brine collecting well, a seepage-dissolution filtering field from one side of supplementing water to the brine collecting end is formed in a dropping funnel, and dynamic ore dissolution is carried out on the supplementing water flowing through the block section. The goaf is enabled to continuously restore the water level, residual brine, solid potassium ores and potassium minerals distributed in a star-like manner in the stratum are dissolved, and brine recovery is achieved when the average content of potassium ions in the brine in the block section is more than 2 g/l. The brine exploitation at this stage is the leaching exploitation. Through repeated cyclic exploitation, combined with drainage and driving exploitation, the total exploitation amount of the original brine ore can be more than 95%, and the leaching recovery rate of the solid potassium ore (substance) can be more than 60%.

And (5) leaching and rotary mining. The leaching of solid potassium by leaching exploitation is a dynamic seepage-leaching circulation process, and needs to be continuously carried out until the hydraulic gradient is gradually reduced, the water level is gradually recovered, and the phenomenon that solid potassium minerals cannot be fully leached due to water-passing shortcuts caused by various natural channels in the stratum is avoided. The water replenishing during the leaching type mining and the driving type mining is continuous, and the water replenishing during the driving type mining is started to carry out leaching on the solid potassium minerals. Because the water is small in specific gravity, the water can float on the water after contacting with the original brine, and in addition, no mixing space exists in the stratum, so that the water is connected with the original brine of the stratum end to end, the seepage path is basically consistent, the water is deficient in potassium, and potassium minerals are dissolved into liquid phase when meeting in the seepage process, thereby achieving the purpose of exploiting solid potassium. The difference is that when the driving type mining is performed, the brine mining end is used for continuously mining brine, and the brine is the original brine during the deposition of ore formation. When the leaching type mining is performed, the brine mining end is used for intermittent brine mining. And when the production is stopped, the water level of the make-up water is gradually recovered in a seepage-leaching mode. The whole water supplementing-seepage-dissolving and filtering process is a process of mixing the water supplementing with the residual raw brine in the salt layer, dissolved salt mineral solution such as sodium potassium and the like to form regenerated brine with high potassium content, and the raw brine is replaced by the regenerated brine.

The periphery of the central mining area is provided with a plurality of peripheral mining areas, the mining areas enter a dissolving filtering type mining stage, a mining mode of multi-area regional wheel-driven mining is implemented, the mining synchronization is ensured, one mining area stops mining, the other mining areas continue to normally mine halogen, the wheel-driven mining interval period is more than 12 months/round, and when the average potassium ion content of the brine is more than 2g/l, the mining is carried out again. After the content of potassium ions in brine in the block sections is generally lower than 2g/l through repeated wheel-driven exploitation, the exploitation of each block section of the brine exploitation area is completed.

The development sequence of each mining block section in the mining area is sequentially carried out from edge to center, so that the mineral development of the mining area is ensured to be carried out from edge to center, the mineral layer is from thin to thick, and the mineral layer is from lean to rich in order and is efficiently utilized.

And (5) preparing and utilizing the makeup water. The method comprises the steps of preparing the waste sodium salt Tian Rongjie stone salt filled with stone salt by injecting the river and lake water around a mining area, preparing the waste sodium salt Tian Rongjie stone salt by using production tailings (mainly comprising stone salt) and waste liquid and natural river and lake water, preparing the salt shell on the surface by using the natural river and lake water, and selecting various modes to prepare according to the utilization conditions and the convenience of water supplementing. The main indexes of the makeup water preparation liquid are mineralization degree and sodium ion content, wherein the mineralization degree is 100-280g/l, and the sodium ion content is 40-80g/l. The mineralization degree and the sodium ion content can be selected according to the structural structure of the salt layer containing the halogen water and the conditions of the overlying production and living facilities of the salt layer, the salt layer is compact, the water with lower mineralization degree and the sodium ion content is generally used for supplementing the water with higher mineralization degree and the sodium ion content in the early stage of supplementing, the damage to a stone salt skeleton is avoided, the water with longer supplementing path and longer dissolving and filtering salt layer time are used for the middle and later stage of supplementing, the water with lower mineralization degree and the water with higher sodium ion content is generally used for the area needing to control the subsidence of the ground, and the water with higher mineralization degree and the water with higher sodium ion content is needed to be used for the area needing to be controlled.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.

Claims

1. The method for mining the salt lake mineral products in a segmented and progressive linkage manner is characterized by comprising the following steps of:

S1, dividing areas into block segments:

2. The method for block-segmented progressive linkage mining of salt lake mineral products according to claim 1, wherein in step S1, the brine-water replenishing process comprises laying brine producing wells, brine producing channels, brine conveying channels and corresponding mining auxiliary facilities in each brine producing area to form a brine-brine replenishing-brine-flooding-ore-dissolving integrated mining system consisting of brine producing well lines, brine producing channel systems, brine conveying channel systems and mining auxiliary facilities; the exploitation auxiliary facilities comprise brine extraction, brine delivery, water supplementing, power supply and pre-evaporation concentration salt fields.

3. The method for mining salt lake mineral products in a segmented and progressive linkage manner according to claim 1, wherein in step S4, the mining step is to first center the mining area, form a brine water level dropping funnel, and then perform brine mining and water supplementing in the peripheral mining area; the water supplementing principle of the supplementing water is that the side block sections of the mining area are continuously conducted from the side block sections to the center block section step by step; in order to adequately ensure percolation time, percolation mining requires wheel mining at multiple peripheral mining areas.

4. The method for mining salt lake mineral products in a segmented and progressive linkage manner according to claim 1, wherein in the step S3, after the potassium and lithium contents in the brine are reduced due to continuous replenishment of the makeup water, the salt lake mineral products are pre-evaporated and concentrated by a solar salt field to meet production requirements.

5. The method for mining salt lake mineral products by block segmentation and progressive linkage according to any one of claims 1 to 4, wherein the makeup water is prepared by utilizing waste sodium salt of a salt pan and potash fertilizer to produce tailings and tail liquid, and surface salt shells and peripheral river and lake water of the salt lake.

6. The method for mining salt lake mineral products in a segmented and progressive linkage manner according to claim 5, wherein the mining area needs to monitor the average potassium ion content of the water block segment in the mining process, and normal brine is adopted when the average potassium ion content of the brine is more than 2 g/l; when the average potassium ion content of the brine is less than 2g/l, the exploitation of the block is stopped.

7. The method for segmented, progressive and linked mining of salt lake mineral product of claim 6 wherein the central mining area is on one side of the entire mining area and the peripheral mining areas are in a fan-shaped distribution or other different distribution patterns.

8. The method for mining salt lake mineral products in a segmented and progressive linkage manner according to claim 6, wherein the bottom boundary burial depth of the salt mineral layer is more than 20m, the thickness is more than 0.5m, the brine production well is mainly arranged, the brine production canal is assisted, and the brine production well must be penetrated through all the salt mineral layer and the halogen-containing water layer; the diameter of the brine production well hole is 500-1500mm, the well depth is 3-6m below the bottom plate of the aquifer, and the brine production well hole is used as a salt particle sediment settling section; selectively discharging a water filtering pipe or a bare hole according to hydrogeology requirements according to different stratum structure and different clastic interlayers, and discharging a hole protecting pipe at a wellhead; and pumping brine from the deep well submersible pump to a position 1-5m away from the bottom boundary of the aquifer, when the thickness of the aquifer is large and the burial depth of the bottom boundary is more than 50m, pumping down to the position 2/3 of the well depth or selecting a position below a stable water level according to the brine pumping strength, and adjusting the position of the lower pump along with the lowering of the water level.

9. The method for block-segmented progressive linkage mining of salt lake mineral product according to claim 6, wherein the bottom boundary burial depth of the salt mineral layer is less than 20m, the thickness is more than 0.5m, the brine collecting channel is mainly used, the brine collecting well is auxiliary, and the brine collecting channel must be deep into or dig through the mineral layer and the halogen-containing water layer; the depth of the brine collecting channel is less than 20m, and the width of the channel bottom is 1-3m; the length of the brine collecting channel is the same as the connecting line length of the brine collecting well, and brine collecting pump stations are erected at one end or two ends or suitable positions of the brine collecting channel.

10. The method for block progressive linkage mining of salt lake mineral products of claim 6, wherein in the dissolving-filtering type mining, the mining mode of multi-zone rotary mining is implemented, so that the mining synchronization is ensured, one brine mining area stops mining, the other brine mining areas continue normal brine mining, and the rotary mining interval is more than 12 months/round.