88 results about "Weathering crust" patented technology

The invention provides a leaching method of weathered crust illuviation type ion rare earth ore and relates to improvement of a wet metallurgical rare earth leaching process. The leaching process of the leaching method comprises adding a leaching agent for leaching. The leaching method is characterized in that fulvic acid is further added in the leaching process of the leaching method as a leaching aid. The leaching method of weathered crust illuviation type ion rare earth ore provided by the invention obviously prompts the column leaching effect of rare earth while reducing the dosage of ammonium sulfate, reduces the dosage of the leaching agent ammonium sulfate while improving the rare earth leaching rate, and also effectively reduces the rare earth extraction cost and generation of ammonia-nitrogen wastewater.

The invention provides a recognition method and a device of effective reservoirs of the dolomite of the karstic weathering crust. The method comprises the following steps of: establishing a sedimentary facies belt interpretation model for reservoir logging of the dolomite of the weathering crust; establishing a characteristic chart library for different sedimentary facies belts in the reservoirs of the dolomite of the weathering crust; establishing corresponding relation of different karstic facies belts and effective reservoirs on the basis of typical characteristics of electric imaging of different karstic facies belts and the actual test oil data in an oil field; carrying out recognition on the effective reservoirs in a two-dimensional plane determined by the inclination angle of the formation interface and the productivity of the effective reservoirs; carrying out calculation of mean values and variances on the basis of a porosity spectrum of the electric imaging, determining lower limit values of the porosity and the variance of the effective reservoirs in the two-dimensional plane formed by the mean values and the variances, and carrying out further recognition on the effective reservoirs; recognizing the effective reservoirs of the dolomite of the weathering crust by combining data such as the developmental state of the sedimentary facies belts in the reservoirs of the weathering crust, the size of the inclination angle of the overlying formation and the distribution condition of the mean values and the variances in the porosity spectrum of the electric imaging.

The invention provides a weathering crust illuviation-type rare-earth ore leaching agent and a method for extracting rare earths by using the same, particularly a leaching agent solution for weathering crust illuviation-type rare-earth ores. The active component is citrate, wherein the citrate is any one of ammonium citrate, sodium citrate, potassium citrate and magnesium citrate, or mixture of sodium citrate, potassium citrate and magnesium citrate. The method for extracting rare earths from weathering crust illuviation-type rare-earth ores comprises the following steps: leaching by using the citrate as the active component of the leaching agent to obtain a rare-earth leaching mother solution, removing impurities, and adding a precipitant to obtain a rare-earth enriched substance. In the weathering crust illuviation-type rare-earth extraction process, cation exchange interaction and anion (citrate ion) complex action exist, and the two actions can cooperate to enhance the rare-earth recovery rate and lower the concentration and consumption of the leaching agent.

The invention provides an impurity-inhibiting leaching method for inhibiting leaching of aluminum during weathering crust eluvial type rare earth ore leaching process. The method comprises that acetates are added in an ore leaching solution, the ore leaching solution is an ammonium sulfate solution or an ammonium chloride solution or a composite ammonium salt solution composed of the above solutions, the acetates are any one of ammonium acetate, sodium acetate and potassium acetate or any mixture thereof, and the addition amount of the acetates in the ore leaching solution is 0.005wt%-2wt%. In the method, the addition of the aluminum inhibitors can lower the aluminum ion content in the rare earth leaching solution by above 91% effectively, and has no influence on the leaching rate of rare earth, which are beneficial to subsequent processing of the rare earth mother solution. The addition of the aluminum inhibitors can inhibit expansion of clays well. The acetates are non-poisonous and the cost is low.

The invention belongs to the field of wet metallurgy and in particular discloses a compound leaching agent for preventing landslide in the process of leaching weathering crust deposit type rare earth ore in situ. The compound leaching agent consists of a mixed aqueous solution of an organic amine salt anti-swelling agent, a leaching agent and a pH regulator, wherein the concentration of the organic amine salt anti-swelling agent is 1-15g / L; the concentration of the leaching agent is 5-30g / L; the pH value of the mixed aqueous solution is regulated to be 4.0-6.0 by using the pH regulator. The compound leaching agent is preferably any one of dimethylamine hydrochloride, di-n-propylamine hydrochloride, diethylamine hydrochloride and triethylamine hydrochloride. Due to the addition of the anti-swelling agent, the compound leaching agent has the capacity of well preventing swelling of clay minerals, the rare earth leaching effect is not influenced, the leaching agent has the functions of leaching and preventing swelling, and landslide is effectively avoided in the process of leaching the weathering crust deposit type rare earth ore in situ.

The invention discloses a method for recovering rare-earth ions from a weathered crust illuviation-type rare-earth ore leaching solution, which comprises the following steps: (a) leaching weathered crust illuviation-type rare-earth ores with an ammonium salt to obtain a rare-earth leaching solution; (b) modifying a biological adsorbent with dianhydride compounds and N,N-dimethylformamide in an anhydrous environment; (c) adding the modified biological adsorbent into the rare-earth leaching solution, adsorbing under the condition of certain acidity, and carrying out solid-liquid separation to obtain the rare-earth-ion-adsorbed modified biological adsorbent; and (d) calcining the rare-earth-ion-adsorbed modified biological adsorbent to obtain the rare-earth oxides. The method for recovering the rare-earth ions from the rare-earth leaching solution by using the modified biological adsorbent reduces the discharge of toxic and harmful substances in industrial production, utilizes the abundant waste biological adsorbent, and is a green environment-friendly technique for extracting and recovering rare earths.

The invention relates to a volcanic rock weathering crust identification and classification standard based oil and gas exploration method. The volcanic rock weathering crust identification and classification standard based oil and gas exploration method comprises sorting basic data, performing well selection at the target position, establishing a water volcanic rock stratum contained volcanic rock weathering crust secondary porosity well logging evaluation model, establishing an oil-gas cement quality volcanic rock stratum contained volcanic rock weathering crust secondary porosity well logging evaluation model, obtaining a secondary porosity index in an oil-gas cement quality volcanic rock weathering crust, establishing a volcanic rock weathering crust structural identification and classification standard and performing oil and gas reserve evaluation according to structural characteristics of a volcanic rock weathering crust. According to the volcanic rock weathering crust identification and classification standard based oil and gas exploration method, the problem that analysis test data are less in the past and accordingly quantitative identification and classification cannot be performed on the volcanic rock weathering crust structure is solved, the area range of the identification and classification of the volcanic rock weathering crust structure is widened, and accordingly the oil field scientific research personnel can identify and classify out the volcanic rock weathering crust structure easily and the establishment of the volcanic rock weathering crust well logging evaluation models and the identification and classification standard is scientific and universal.

The invention relates to the technical field of intercepting of leaching solution of weathering crust elution-deposited rare earth ores in south China, and provides a weathering crust elution-deposited rare earth ore leaching solution intercepting technology according to landforms and geological characteristics of rare earth mines in view of the shortages in application of an in-situ ore leachingprocess in the weathering crust elution-deposited rare earth mines under complex geological conditions in order to improve the leaching solution recovery rate, reduce leaching solution seepage and enhance applicability of the in-situ ore leaching process. The weathering crust elution-deposited rare earth ore leaching solution intercepting technology mainly comprises four work procedures of solution-collecting roadways, flow guiding holes, cutting of pull grooves and anti-seepage treatment; the solution-collecting roadways are arranged at a bottom plate on the lower portion of a weathering crust elution-deposited rare earth ore body and parallel to the mountain body trend; the two rows of flow guiding holes are obliquely upwards drilled in the two side walls of the solution-collecting roadways, and the flow guiding holes are formed in a staggered mode; the pull grooves are formed in the two sides of the flow guiding holes in a cutting mode, and the pull grooves and the flow guiding holes form the manual intercepting bottom plate which can intercepts the more than 90% of leaching solution flowing through a region; and arcs on the lower parts of the pull grooves and the lower half parts of the flow guiding holes are grouted for seepage preventing, and anti-seepage treatment is conducted on the bottom surfaces of the solution-collecting roadways.

The invention discloses a method for extracting rare earth from weathered crust strain amass type rare earth ore. The weathered crust strain amass type rare earth ore is leached through a leaching agent to obtain rare earth lixivium; then an alkaline calcium compound is added into the rare earth lixivium to carry out impurity removal and sedimentation, and rare earth hydroxide sediment residues are obtained; an organic auxiliary containing solution is adopted for stirring and washing, and the total molar concentration, the liquid-solid ratio, temperature, pH and the like of an auxiliary are controlled; and the auxiliary is combined with calcium in the sediment residues, calcium sulfate in the residues is dissolved, and therefore the final product purity is improved. In addition, through adding of the auxiliary, the auxiliary can return to be used for ore leaching, the function of enhancing leaching is achieved under the acid condition, and the leaching rate of the rare earth is improved. According to the method, ammonia nitrogen pollution is removed, the rare earth leaching rate is increased, meanwhile, formed calcium sulfate in the sediment process of the alkaline calcium compound is reduced, production cost is reduced, and meanwhile products with qualified purity are obtained.

The invention relates to a method and a device for exploring carbonate rocks with weak seismic reflection features. The method comprises the following steps of: acquiring contrary sub-waves of target stratum seismic reflection waves of carbonate rock inner weathering crusts of at least two wells; acquiring reflection coefficients of the top parts of the carbonate rock inner weathering crusts of the wells according to calibrated weathering crust seismic reflection features of the wells; loading seismic interpretation positions of the target stratums of the carbonate rock inner weathering crusts to a common reflection point trace set so as to acquire seismic sampling points, and acquiring target stratum position reflection coefficients according to the contrary sub-waves and the seismic sampling points; comparing the reflection coefficients of the top parts of the carbonate rock inner weathering crusts with the target stratum position reflection coefficients so as to judge whether the target stratum positions are superior channels; if the reflection coefficients of the top parts of the carbonate rock inner weathering crusts is judged as being accordant with the reflection coefficients of the top parts of the carbonate rock inner weathering crusts, the target stratum positions are superior channels; and overlapping the superior channels so as to acquire seismic data, and exploring the carbonate rocks with the weak seismic reflection features according to the acquired seismic data.

The invention provides a quick impurity removing method for the rare earth leach liquor of weathering crust elution-deposited rare earth ores, and aims to solve the problems that the content of metal ions of impurities in the leach liquor of the weathering crust elution-deposited rare earth ores is high, a conventional impurity removing method is longer in process flow and complicated in operation, the precipitation and sedimentation speed of generated flocculated impurities is lower, and the quantity of adsorbed and carried rare earth is large. The method specifically comprises the following steps of (1) directly adding a mixed solution of ammonium hydrogen carbonate and inorganic sulfide into the rare earth leach liquor; (2) adding ammonia water or sulfuric acid to adjust the pH value of the mixed solution; (3) under the condition of stirring, adding a flocculating agent solution into the mixed solution, continuously stirring for 1h to 3h, then standing for sedimentation, and extracting supernatant liquor to obtain low-impurity rare earth leach liquor. According to the method, the sedimentation time of the impurities can be effectively shortened, the production efficiency is greatly improved, quick and full sedimentation of the impurities can be achieved, the rare earth of the obtained low-impurity rare earth leach liquor is high in recovery rate and high in purity, and the method is suitable for popularization and application.

The embodiment of the invention provides a carbonate rock crack hole reservoir prediction method and device. The method includes the steps that seismic data are prepared; seismic horizon interpretation is performed on the seismic data; the average speed of converted shear waves is generated by the seismic data; the gradient data body and the intercept data body of the converted shear waves are obtained according to the seismic data and the average speed of the converted shear waves, and a lithological character indicator factor data body is generated according to the gradient data body and the intercept data body of the converted shear waves; a simulated hole coefficient data body is generated according to the lithological character indicator factor data body; longitudinal waves and converted shear waves are matched, and the longitudinal span range of the time domain of the wave field of the converted shear waves is determined; according to the simulated hole coefficient data body and the longitudinal span range of the time domain of the wave field of the converted shear waves, carbonate rock weathering crust crack hole reservoirs can be predicted.

The invention relates to a method for leaching rare earth from weathering crust leaching type rare-earth ore heap. The method comprises the following steps: (1) stripping humus layer ore soil of weathering crust leaching type rare-earth ore; (2) selecting the storage yard site; (3) constructing the storage yard, namely laying a leakproof layer on the compacted site, laying a wood frame, covering a linen piece, stacking a completely weathering layer and a half weathering layer on the site to form the storage yard, and finally flattening and topping; (4) performing heap leaching and extracting the rare earth, namely adding an ammonium salt ore leaching agent into the storage yard from the heap top by virtue of a liquid adding pipe, naturally downwards penetrating the ammonium salt ore leaching agent, collecting the rare-earth leaching mother solution from a confluence trench at the bottom of the storage yard, and precipitating and recycling the rare earth by using oxalic acid or ammonium bicarbonate; and (5) recovering the vegetation. The rare-earth leaching solution obtained by the method is small in amount of impurities, the rare-earth product is high in purity, the later-stage vegetation recovery is promoted, and high-efficiency and green mining can be realized.

The invention relates to a rapid economic evaluation method of ionic adsorption rare earth ore. The method comprises the following steps: carrying out geological exploration to collect geological survey borehole data and borehole sampling and testing data of a target mine area and establishing an ore deposit borehole database; performing 3D ore body modeling by using the borehole data and performing grade interpolation by using a kriging method to obtain an ore deposit ore body model; performing price sensitivity analysis by acquiring a large quantity of mineral products market data and establishing a mineral product price-boundary grade calculating model; using the model to determining the boundary grade of a specific ore deposit under different market prices and then using the boundary grade to constrain the ore deposit ore body model and to delineate an ore body range, and then performing reserves calculation. According to the change of the market price and the operating cost of the enterprise, the profit and loss balance point is determined according to the basic geologic characteristics of the weathering crust and the distribution of the rare earth elements, and the boundary grade and the industrial grade are determined by comprehensively considering the profit margin and the like. further, computer technology is used for delineating the ore bodies and to calculate the reserves of resources, and providing the basis for the reasonable determination of a mining plan.

The invention relates to a method for measuring the cation exchange capacity of a weathered crust illuviation rare earth ore. The method comprises the following steps of: (1) drying: drying a weathered crust illuviation rare earth ore sample; (2) exchanging and eluting; (3) distilling and absorbing ammonium; (4) measuring the ammonium; and (5) calculating the cation exchange capacity of the weathered crust illuviation rare earth ore sample according to a calculation formula. The invention has the beneficial effects that: the defect of the conventional measurement of the cation exchange capacity of a weathered crust illuviation rare earth ore is overcome, the method is suitable for measuring the cation exchange capacities of various weathered crust illuviation rare earth ores, an operationdevice is simple, the cost is low, and high analysis accuracy and repeatability are achieved.

The invention discloses an in-situ leaching and leakage interception method for weathered crust rare earth ore. The method comprises the following steps that a liquid injection well and a guide hole are formed for rare earth ore, a liquid collecting reservoir is arranged, then water catchment planes of different heights are found at the foot of a mine, a multi-stage interception pool is established in sequence from high to low, and according to the effusion rare earth content conditions collected by the multi-stage interception pool, collected effusion is used as a rare earth leaching solutionor recovered and applied to preparing a leaching solution. The concept of further introducing the multi-stage interception pool on the basis of a leaching solution recovery system for a weathered crust rare earth ore in-situ leaching process is first proposed, leakage of the leaching solution containing a rare earth and ammonium salt leaching agent is effectively prevented or reduced, ammonia-nitrogen wastewater pollution to underground water and surface water is effectively reduced, the rare earth recovery rate is remarkably increased, consumption of the leaching agent is reduced, and remarkable environmental and economic benefits are achieved.

The invention belongs to the technical field of wet metallurgy, and provides a method for weathering crust elution-deposited rare earth ore leaching agent ammonium bicarbonate rare earth precipitatingmother liquor reusing and rare earth recovery. The method is provided for solving the problems that the use amount of hydrogen carbonate in existing weathering crust elution-deposited rare earth oreleaching agent is too large, a large amount of leaching solvents of ammonium sulfate or ammonium chloride contain, serious ammonia nitrogen wastewater pollutions and resource waste are caused, and when an existing production process recycles rare earth precipitating mother liquor, sulfuric acid needs to be used for removing residual ammonium bicarbonate. The rare earth ore leaching agent ammoniumbicarbonate rare earth precipitating mother liquor is reused in a circulating manner for recycling rare earth; in the whole rare earth recycling process, the use amount of ammonium bicarbonate is regulated and controlled, the rare earth precipitation recycling rate is ensured, reusing of the mother liquor obtained after rare earth precipitating does not affect the leaching rate of rare earth, efficient recycling of the rare earth resources under the non-acid condition can be achieved, and the important economic and environment benefits are achieved.

The invention discloses a method for finely restoring karst paleogeomorphology in the technical field of paleogeomorphology restoration. The specific steps of the method for finely restoring karst paleogeomorphology are as follows: S1: Find a relatively accurate representative paleosea in the overlying stratum of ancient weathering crust Plane stratigraphic depositional interface; S2: Obtain the relative height of the topography on the weathering crust through the stratum thickness between the depositional interface and the weathering crust; S3: Use the method of high-resolution sequence stratigraphy to calculate the relative height of the topography in step S2 S4: Construct the seismic profile; S5: Analyze the seismic profile features on the seismic profile, and restore the karst ancient landform. The restoration image of the karst ancient landform in the present invention is intuitive and realistic, with low cost and easy Realized that the restoration of ancient landforms is relatively complete, and at the same time, the impact of the later structure of the landforms is considered, and the restoration accuracy is high.

The invention relates to the field of wet metallurgy, in particular to a composite leaching agent for enhanced leaching of weathered crust elution-deposited rare earth ores and a preparation method thereof and a method for extracting rare earth. The composite leaching agent for enhanced leaching of the weathered crust elution-deposited rare earth ores comprises 1-4 % of an inorganic leaching agentand 0.1-1.2% of one or a combination of more of dimethyl diallyl ammonium chloride, 2-chloroethyl trimetyl ammonium chloride, an acrylamide and dimethyl diallyl ammonium chloride copolymer and acrylamidetrimethyl allyl ammonium chloride according to the mass percentage. The method for extracting the rare earth comprises the step of using the composite leaching agent for enhanced leaching of the weathered crust elution-deposited rare earth ores to leach the rare earth in the rare earth ores. Under the coordination between the inorganic leaching agent and an organic stabilizer, the weathered crust elution-deposited rare earth ores are leached in situ, the permeation of the leaching agent and the leaching process of the rare earth are enhanced, the consumption of the leaching agent is reduced, the expansion of the clay minerals is inhibited, problems that stability of the weathered crust elution-deposited rare earth ores is low and the weathered crust elution-deposited rare earth ores are easy to generate landslide due to the inorganic leaching agent are solved, and the exploration period is also shortened.

The invention relates to a treatment method of waste water generated by mining weathering crust eluvial type rare earth mine. Adsorption treatment is carried out by virtue of cation resin and anion resin. The treatment method comprises settling, filtering, absorbing, waste water detecting and PH value adjusting. Collected waste water is firstly settled, then is discharged to a filter tank to be filtered by quartz stone or anthracite, then is discharged to an absorption tank so that ammonia nitrogen, cation and anion in the waste water are absorbed by the cation resin and the anion resin; then the waste water is discharged to a detection tank for detecting whether the waste water reaches the standard; if reaching the standard, the waste water is discharged to a PH value adjustment tank for adjusting PH value to reach standard, and then directly discharged to the otuside. When rare earth is found in the detection tank, the cation resin and the anion resin are desorbed by utilizing ammonium chloride or sodium chloride; liquid obtained after desorption is treated like mother liquid mined from a rare earth mine; impurities are removed and rare earth is recycled; water with rear earth settled can be used as a leaching agent for mining or used as a farm-oriented fertilizer. After being desorbed, the cation resin and the anion resin in the absorption tank can be recycled.

The invention discloses a formate compound extracting agent for weathering crust elution-deposited rare earth ore. The formate compound extracting agent contains formate solution and ammonium salt solution. Compared with the extracting effect of a traditional extracting agent, the formate compound extracting agent is capable of accelerating a seepage velocity of the extracting agent in an ore body, effectively shortening extraction time of rare earth in the preconditions without affecting a rare earth extracting rate, and effectively inhibiting the extracting of impurity aluminum, beneficial to follow-up impurity-removing working procedures of rare earth mother liquor, and capable of realizing the efficient low-impurity extracting of the weathering crust elution-deposited rare earth ore. The formate compound extracting agent is non-toxic in formate raw material, less in addition amount, low in cost, biodegradable, green and environment-friendly.

The invention discloses a weathered crust recognition device which comprises a signal collector, a filter, a wireless emitter and a wireless receiver. The signal collector is installed at the top of a drill column and used for collecting vibration sound waves generated when rock is broken by a drill bit. The filter is connected with the signal collector. The wireless emitter is connected with the filter and used for emitting the vibration sound waves filtered by the filter. Wireless communication between the wireless receiver and the wireless emitter is achieved through electromagnetic waves. The wireless receiver is connected with an external computer. The computer generates vibration sound wave frequency spectrum. The weathered crust recognition device can effectively extract the characteristics of vibration sound wave frequencies of the upper formation lithology and the lower formation lithology of weathered crust.

The invention provides a method for eluting residual ammonium salt in a closed mine field of weathering crust elution-deposited rare earth ore, and relates to the field of mining area pollution control and soil remediation. The method comprises the following steps that (1), a metal salt solution is injected into the closed field of the weathering crust elution-deposited rare earth ore for elutionand removal so as to obtain a residual ammonium salt-containing eluate, wherein the mass ratio of the metal salt solution to the rare earth ore is (1-3):1; and 2), and the residual ammonium salt-containing eluate is collected into a liquid collecting tank through a flow guide hole for ammonia nitrogen centralized treatment. According to the method, in the first step, the metal salt solution is injected into an original liquid injection pipe in the closed mine field subjected to heap eluting or in-situ eluting to serve as an eluting agent, then eluting liquid is collected through the flow guidehole to be subjected to ammonia nitrogen centralized treatment; and compared with the process that the residual ammonium salt in the closed mine field is directly eluted and removed through clear water, the method is high in efficiency and low in cost, and a large amount of residual ammonium salt ore eluting agent in the closed field of the weathering crust elution-deposited rare earth ore can beefficiently eluted and removed.

The invention relates to the field of hydrometallurgy, in particular to an ore leaching method of weathered crust ion-adsorption type rare earth ore and a rare earth product. The ore leaching method of weathering crust ion-adsorption type rare earth ore comprises the following steps that the weathering crust ion-adsorption type rare earth ore is leached with a leaching agent, and a rare earth leaching solution flowing out from the bottom of ore soil is collected twice; and after impurities are removed and rare earth is precipitated from the rare earth leaching solution collected for the firsttime, the rare earth leaching solution is mixed with the rare earth leaching solution collected for the second time, the leaching agent is added, and a mixed solution is returned to the rare earth oreas a fresh leaching agent for leaching operation. The ore leaching method is simple and feasible, the operation load of hydrometallurgy work is reduced, and economic and environment protection are achieved.

The invention discloses an extraction method of weathering crust elution-deposited rare earth ore. According to the extraction method, a biological leaching and organic acid (salt) combined leaching process is mainly adopted in the leaching stage, clean and efficient extraction of rare earth resources is achieved on the premise that the environment is not polluted, and the extraction method has the advantages of being good in leaching effect, low in cost, environmentally friendly and the like. According to the process, impurity dissolution can be reduced, and the rare earth separation efficiency and the product quality can be improved; microorganisms and metabolites of the microorganisms can enhance the permeability of a leaching agent, reduce leaching blind areas and increase the effective utilization rate of the rare earth resources, and pollutant degradation and ecological restoration are partially facilitated; and rare earth elements are enriched through solvent extraction and reverse extraction technologies, and then a high-quality rare earth product can be obtained through a precipitation method.

The invention discloses a method for strengthening leaching of weathering crust elution-deposited rare earth ore by utilizing an additive. The method comprises the following steps of: preparing a salt ion leaching agent and the additive into an aqueous solution according to a set concentration, then adjusting the pH of the solution to obtain a leaching solution, and then performing column leaching on the weathering crust elution-deposited rare earth ore by using the leaching solution to obtain a leaching solution containing rare earth elements. The method disclosed by the invention improves the leaching efficiency of rare earth ions, effectively reduces the use concentration and the use amount of the salt ion leaching agent, and reduces ammonia nitrogen and salt ion pollution; by adding small molecular organic acid, the dissolution of impurity elements can be inhibited, the subsequent impurity removal process is simplified, and the separation efficiency of the rare earth elements in the subsequent leaching solution is improved; and the additive adopted in the method has the advantages of environmental protection, low cost, high efficiency, easily available raw materials and the like, is beneficial to ecological restoration and improvement, and has a relatively good application value.

The invention discloses a method for leaching weathering crust leaching type rare earth ore by using a plant extract. The method comprises the following steps of (1) preparing a plant extracting solution; and (2) leaching the weathering crust leaching rare earth ore by utilizing the plant extracting solution. According to the method, the plant extract is adopted as a leaching agent or an auxiliary leaching agent of the weathering crust leaching type rare earth ore, and the plant extract contains rich organic matters (such as phenols, ketones and organic acids), so that rare earth elements can be efficiently leached out. The method is good in leaching effect, environmentally friendly and low in cost, raw materials are easy to obtain, plant extract components are beneficial to ecological restoration and improvement, and the method has good application value.

The invention discloses a weathered crust karst fracture-cavity type oil reservoir oil well water breakthrough time prediction method based on machine learning. The method comprises the following steps of S01 determining the karst background of a fractured-vuggy oil reservoir to be weathered crust karst, and determining the reservoir type of a reservoir where an oil well is located; S02 identifying the oil pressure change type of the water-seen high-yield oil well by using a knn algorithm; S03 establishing a characteristic corresponding relation between the fracture-cavity reservoir driving stage and the oil well oil pressure stage; S04 establishing a quantitative plate of each reservoir type of the fracture-cavity oil reservoir; S05 counting water breakthrough influence factors and waterbreakthrough time of the fracture-cavity oil reservoir oil well; S06 determining an initial clustering center k of the fracture-cavity reservoir oil well; S07 establishing a mean value clustering prediction model of the water breakthrough time of the fracture-cavity type oil reservoir oil well. According to the present invention, the water breakthrough early warning quantitative chart and water breakthrough time k-means clustering prediction method has the advantages of being wide in application range, being easy to operate and the like, and being able to quickly guide adjustment of on-site measures.

The invention provides a method for evaluating the water-resisting property indexes of a Middle Ordovician limestone ancient weathering crust. According to the technical scheme, the method is characterized by including the following steps that firstly, it is determined that water-resisting property indexes are depicted; secondly, thematic maps of the water-resisting property indexes are established; thirdly, weight coefficients of the indexes are determined based on the information fusion technology; fourthly, the thematic maps of the water-resisting property indexes are overlapped; fifthly, a water-resisting property evaluation model is established; sixthly, the water-resisting property is divided and evaluated. A mine lot is divided into five sub lots, a weak water-resisting property lot, a weaker water-resisting property lot, a transition water-resisting property lot, a stronger water-resisting property lot and a strong water-resisting property lot. The method for evaluating the water-resisting property indexes of the Middle Ordovician limestone ancient weathering crust is provided for the first time, and the water inrush evaluation and prediction defects that in the mining practice, the water inrush phenomenon never occurs on many water inrush points with the values far larger than a critical value in the seam floor water inrush evaluation process are overcome.

The invention discloses a profile control and displacement system suitable for a carbonate weathered crust reservoir. The system comprises, by mass, 0.5-2% of nano-silica, 0.01-3.0% of a quaternary ammonium salt surfactant, and the balance of water. The invention also discloses a preparation method of the system. The preparation method comprises the following steps: adding the nano-silica into water at room temperature, performing stirring, and carrying out ultrasonic treatment to achieve uniform dispersion in water; and adding the quaternary ammonium salt surfactant, and performing stirring to fully dissolve the surfactant in order to obtain the system. The profile control and displacement system adopting the quaternary ammonium salt surfactant and the easily available silica nano-material has the advantages of certain decompression and augmented injection effect, good stability, good stratum injectivity, good interface stabilizing ability and good emulsification performance, plays arole in oil displacement, and also can be used for the profile control of the stratum.