A short-process, low-cost cyanidation gold extraction system and its control method

Abstract

The invention discloses a short-process low-cost cyanidation gold extraction system and a control method thereof, and belongs to the technical field of precious metal refining. The inside of the leaching tank is covered with gold-containing ore, and an alkaline cyanide solution or an environmentally friendly gold extraction agent solution is injected. A drainage pipe is arranged on the top of the leaching tank, and a drainage ditch is arranged at the bottom. On one side of the leaching tank, a seepage collection tank, a sedimentation tank, a precious liquid tank, and a lean liquid tank are excavated and constructed on the spot below the surface, and a carbon adsorption tank is arranged. The lean liquid is regularly returned to the leaching tank through a submersible pump and a boiling pulping device, which improves the leaching efficiency, realizes the natural stratification of the coarse and fine ore, reduces the water content of the cyanide slag after leaching, and plays a role in washing the lean liquid. The invention has low investment cost, short construction period, short process, low production cost, and is easy to operate and control. In addition, the leaching tank, sedimentation tank, sedimentation tank, etc. have simple structures and large volumes, and can obtain higher processing capacity.

Description

Technical Field

[0001] The invention belongs to the technical field of precious metal refining, relates to a cyanidation gold extraction system, and relates to a control method of the cyanidation gold extraction system. Background Art

[0002] Cyanide gold extraction refers to the method of using an aqueous solution of alkali metal cyanide or an environmentally friendly gold extracting agent as a solvent to dissolve the gold in the gold ore, so that the gold changes from a single substance to an ionic state, and then uses zinc powder replacement or electrodeposition in the gold-containing solution to convert the ionic gold into single substance gold, thereby extracting gold from the ore. Cyanide gold extraction mainly includes leaching, washing, carbon adsorption, cyanide slag dehydration and other steps. Among them, leaching is the process of dissolving gold in an oxygen-containing cyanide solution; washing is the process of reducing the gold ion concentration of the gold-containing solution after leaching; carbon adsorption is the process of recovering gold ions from the gold-containing solution after cyanide leaching by adsorption of activated carbon. Cyanide gold extraction involves factors such as the state of gold particles, ore pulp concentration, cyanide or environmentally friendly gold extracting agent concentration, oxygen concentration, pH value and leaching time.

[0003] The traditional cyanide leaching device is a mechanically stirred leaching tank, the tank body of which is made of rolled and welded steel plates, with a hollow shaft and a stirring impeller in the middle. The hollow shaft plays an aerating role, and the impeller plays a stirring role of the ore pulp. The traditional cyanide washing device is a single-layer or multi-layer thickener, which reduces the gold ion concentration of the gold-containing solution in the ore pulp through the countercurrent washing principle to form precious liquid and lean liquid. The above-mentioned device has high engineering cost, long construction period, high energy consumption, and large surface area, which has a certain impact on the new construction or expansion of the cyanide gold extraction system, as well as the daily operation cost control. On the other hand, the use of traditional cyanide leaching devices and cyanide washing devices generally has the defects of low leaching efficiency and high water content of cyanide residue after leaching. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a short-process low-cost cyanidation gold extraction system and a control method thereof, which firstly greatly reduces the system investment cost and floor space, shortens the construction period and process flow, reduces the production cost and the difficulty of operation control, and on this basis further improves the effective volume and processing capacity of the leaching tank, the sedimentation tank and the precipitation tank; secondly, further improves the leaching efficiency and reduces the water content of the cyanide residue after leaching.

[0005] The technical solution of the present invention is as follows:

[0006] A short-process low-cost cyanide gold extraction system comprises a leaching tank, a settling tank, a sedimentation tank, a noble liquid tank and a lean liquid tank, wherein the leaching tank is in a rectangular shape, and a drainage pipe and an overflow pipe located above the drainage pipe are arranged at the end; at least two drainage ditches are arranged along the length direction below the leaching tank, and a drainage device is arranged at the upper end of the drainage ditches; the upper surface of the drainage device has an anti-seepage layer as the bottom surface of the leaching tank, and the bottom surface has a slope with a gradually decreasing height from the head end to the end along the length direction; a boiling slurry device capable of changing position along the length direction of the leaching tank is arranged above the leaching tank; the boiling slurry device comprises a distributor, and the distributor is fixedly connected with a plurality of slurry pipes arranged longitudinally and used for inserting into the material in the leaching tank from top to bottom; A fluid inlet pipe in the form of a hose is connected to one side of the distributor, and the end of the fluid inlet pipe is used to connect a lean liquid pipeline, a clean water pipeline or a high-pressure air pipeline; a crane is provided above the leaching tank for loading gold-containing ore into the leaching tank, digging gold-containing ore from the leaching tank and hanging the boiling pulping device during the leaching process; a seepage collection tank with a bottom lower than the drainage ditch is connected to the end of the leaching tank; the seepage collection tank is connected to the drainage ditch and is internally equipped with a vertical submersible pump for discharging the seepage in the seepage collection tank to the sedimentation tank; the leaching tank is arranged above the ground surface; the seepage collection tank, sedimentation tank, precious liquid tank and lean liquid tank are arranged below the ground surface; a part of the sedimentation tank is above the ground surface, and the other part is below the ground surface.

[0007] Preferably, the settling tank is provided with an overflow trough and a feeding cylinder, and an underflow slurry pump is connected to the bottom end; the feeding cylinder is connected to the overflow pipe, so that the turbid liquid in the upper layer of the leaching tank flows into the settling tank through the overflow pipe and the feeding cylinder in sequence; the underflow slurry pump is connected to the leaching tank through a pipeline, so that the ore pulp settled in the settling tank is discharged back to the leaching tank; the overflow trough is connected to the sedimentation tank through a pipeline, so that the upper clear liquid in the sedimentation tank overflows into the sedimentation tank; the noble liquid tank is connected to the end of the sedimentation tank, So that the gold-containing liquid purified by the sedimentation tank can flow into the precious liquid pool; a carbon adsorption tank is arranged above the precious liquid pool; a precious liquid submersible pump for extracting the supernatant of the precious liquid pool is installed in the precious liquid pool, the water outlet end of the precious liquid submersible pump is connected to the water inlet of the carbon adsorption tank, and the water outlet of the carbon adsorption tank is connected to the lean liquid pool through a pipeline; a lean liquid submersible pump for transporting lean liquid to the leaching tank is installed in the lean liquid pool; sodium cyanide or environmentally friendly gold extraction agent solution addition pipes and lime solution addition pipes are arranged around the lean liquid pool.

[0008] Preferably, there are more than two leaching tanks, which are arranged in parallel in the width direction and whose ends are connected to the same seepage collection tank.

[0009] Preferably, the drainage device includes a drainage plate covering the drainage ditch from the upper side, a geotextile is installed directly above the drainage plate, concrete is poured between the geotextiles above adjacent drainage ditches and between the geotextile and the wall of the leaching tank in the length direction, and the anti-seepage layer is located on the upper surface of the concrete and the geotextile.

[0010] Preferably, a counterweight groove for placing a counterweight block is provided on the top side of the distributor.

[0011] Preferably, the sedimentation tank is composed of multiple sub-tanks operated in series; overflow ports are provided between the sub-tanks, and all sub-tanks are operated in series during normal production. When dredging is required, dredging is stopped individually, and other sub-tanks are operated normally in series.

[0012] Preferably, the number of leaching tanks is calculated and determined according to the following formula:

[0013] formula: ;

[0014] Where G is the number of leaching tanks, pieces;

[0015] K—redundancy coefficient;

[0016] Q—daily processing volume, tons / day;

[0017] t—leaching time determined by boiling pulping leaching test, h;

[0018] a—length of leaching tank, m;

[0019] b—width of leaching tank, m;

[0020] c—thickness of the gold-bearing ore layer in the leaching tank, m;

[0021] ρ—Specific gravity of ore pile.

[0022] Preferably, the settling tank comprises a cylindrical cylinder and a conical cylinder, the overflow tank is arranged on the upper part of the cylindrical cylinder; the feeding cylinder is located directly above the cylindrical cylinder; the lower end of the cylindrical cylinder is connected to the upper end of the conical cylinder, and the bottom end of the conical cylinder is connected to the underflow slurry pump; the diameter of the cylindrical cylinder is calculated using the following formula:

[0023] formula: ;

[0024] In the formula φ —cylinder diameter, m;

[0025] K0—safety factor;

[0026] G—Number of leaching tanks, pieces;

[0027] C1—mass concentration of turbid liquid fed into the sedimentation tank, %;

[0028] C2—mass concentration of underflow slurry discharged from the sedimentation tank, %;

[0029] ρ—true specific gravity of suspended matter in the sedimentation tank;

[0030] S—the mass of suspended solids treated per unit area of ​​the sedimentation tank per unit time, t / (m 2 .h), S=V P / (R1-R2);

[0031] R1—liquid-to-solid ratio when the concentration of turbid liquid fed into the sedimentation tank is C1;

[0032] R2—liquid-to-solid ratio when the concentration of underflow slurry discharged from the sedimentation tank is C2;

[0033] V P —The average settling velocity of suspended matter when a turbid liquid settles to the required underflow concentration, determined by sedimentation experiments, in m / h.

[0034] Based on the control method of the short-process low-cost cyanidation gold extraction system, the steps are as follows:

[0035] Step 1: Use a grab bucket to load gold-bearing ore raw materials into the leaching tank, trim and flatten the surface layer, and form a slope consistent with the anti-seepage layer of the leaching tank from the front end to the end of the leaching tank;

[0036] Step 2: injecting lean solution into the leaching tank, requiring the lean solution to cover the highest point of the gold-containing ore raw material layer;

[0037] Step 3: Use a crane to hang the boiling pulping device from the front end of the leaching tank and perform boiling pulping in sections from front to back; during the boiling pulping process, the boiling pulping device is first filled with high-pressure air, the crane hook falls, and the pulping pipe is inserted into the ore pulp layer to the bottom of the leaching tank; after the high-pressure air is continuously filled in the process, it is changed to be filled with lean liquid; after completion, the crane hook is lifted and moved forward to carry out the next stage of boiling pulping; during the process, part of the liquid is discharged from the bottom of the leaching tank through the drainage plate and the drainage ditch, and then the seepage liquid is discharged to the sedimentation tank for purification through the vertical submersible pump;

[0038] When the lean liquid is charged into the boiling pulping operation, the turbid liquid on the upper layer of the leaching tank is discharged from the end overflow pipe and flows into the sedimentation tank through the feeding cylinder; after the turbid liquid is purified in the sedimentation tank, it overflows into the sedimentation tank for secondary purification; when the concentration of the bottom flow suspended solids reaches more than 40%, it is discharged into the leaching tank where the leaching operation is completed for filtration and dehydration;

[0039] Step 4: After the boiling pulping operation in the leaching tank is completed, let it stand until the supernatant is completely clarified, open the drain pipe, and the supernatant is discharged into the sedimentation tank by gravity; the gold-containing liquid is purified in the sedimentation tank and flows into the precious liquid tank; after the precious liquid recovers gold in the carbon adsorption tank, the barren liquid is discharged into the barren liquid tank;

[0040] During the production process, in order to meet the needs of leaching chemical reactions, sodium cyanide or environmentally friendly gold extraction agent solution and lime solution need to be continuously added to the lean liquid pool according to the consumption. The lean liquid supplemented with sodium cyanide or environmentally friendly gold extraction agent solution and lime solution is fed into the leaching pool or boiling pulping device for recycling through the lean liquid submersible pump.

[0041] Preferably, when the water content in the drainage ditch reaches below 20%, the cyanide slag is removed by a grab bucket.

[0042] Compared with the prior art, the beneficial effects of the present invention are:

[0043] The system of the present invention provides basic conditions for ore leaching by constructing one or several leaching pools on site, filling the interior with gold-containing ore, and injecting alkaline cyanide solution or environmentally friendly gold extraction agent solution. A drainage pipe is set at the top of the leaching pool, and a drainage ditch is set at the bottom, so as to achieve solid-liquid separation and discharge of gold-containing liquid after leaching. On one side of the leaching pool, a seepage collection pool, a sedimentation pool, a settling pool, a noble liquid pool and a lean liquid pool are excavated on site below the surface, and a carbon adsorption tank is set to achieve gold-containing liquid purification and gold ion adsorption recovery. The lean liquid is regularly returned to the leaching pool through a submersible pump and a boiling pulping device, which improves the leaching efficiency, realizes the natural stratification of ore coarseness and fineness, reduces the water content of cyanide slag after leaching, and has the function of washing lean liquid. The cyanide gold extraction system and control method of the present invention can play the roles of leaching, washing, carbon adsorption, cyanide slag dehydration, etc., with low investment cost, short construction period, short process, low production cost, and easy operation and control. In addition, leaching tanks, sedimentation tanks, and sedimentation tanks have simple structures and large volumes, and can achieve higher processing capacity. The details are as follows:

[0044] (1) The present invention can replace the leaching tank, washing and thickening machine, decarbonization screen and filter press in the prior art. The construction cost of the leaching tank, seepage collection tank, sedimentation tank, precipitation tank, precious liquid tank and lean liquid tank is mostly civil engineering investment, and some facilities are constructed by surface excavation. Under the same processing capacity, the investment can be reduced by 70% compared with the prior art, and the occupied area can be reduced by 50%.

[0045] (2) Compared with the prior art, the present invention has facilities such as leaching tanks that can play multiple roles, with one thing having multiple effects, a short process flow, centralized equipment and facilities, simple production operation, easy to realize production automation, and the number of post personnel can be reduced by 30-40%.

[0046] (3) The boiling pulping device in the present invention can timely charge sodium cyanide or environmentally friendly gold extracting agent, lime and air into the leaching pool, and part of the liquid penetrates the ore layer and is discharged from the bottom, which effectively promotes the efficient leaching reaction. Under the continuous boiling pulping operation, the pulping pipe is continuously inserted into the material layer to charge high-pressure air and sodium cyanide or environmentally friendly gold extracting agent solution. In this process, the materials in the pool are constantly boiling and rolling, and the gold-containing particles, oxygen, sodium cyanide or environmentally friendly gold extracting agent are fully dispersed and contacted, which greatly improves the intensity of the leaching chemical reaction and makes it easy to obtain better process indicators. In addition, the gold-containing ore raw materials in the leaching pool are separated into coarse and fine layers, further strengthening the percolation effect. In the process, the water analysis in the coarse particles at the bottom plays a siphoning role on the water in the upper fine particles, further shortening the solid-liquid separation time and reducing the water content of the cyanide slag. In the last boiling pulping process of the present invention, since the lean liquid is used, it can simultaneously play a washing role. In addition, the moisture content of the final cyanide slag in the production of the system of the present invention is often higher than that of the raw materials. For example, in special cases, the moisture content of the raw materials is high. Since the present invention processes the gold-containing ore raw materials intermittently in batches, it can be aired to reduce its moisture content. Under the above conditions, the last boiling pulping can use part of the clean water to further improve the washing effect and reduce the loss of valuable metals.

[0047] (4) In the production process of the present invention, the gold-containing ore raw materials are only loaded and excavated at the beginning and end of the operation, and are placed in the leaching tank for the rest of the time. The process operation only transports and reverses the clarified liquid or the turbid liquid containing a small amount of suspended matter, and most of the gravity transportation is carried out by utilizing the height difference of the facilities. The operation energy consumption is low, and the equipment and facilities are lightly worn. Under the same processing capacity, the operation cost can be reduced by more than 60% compared with the prior art.

[0048] (5) The whole system has a simple configuration, a short process flow, and a greatly reduced probability of leakage. It also achieves water balance and no sewage is discharged, making it essentially safe and environmentally friendly.

[0049] (6) The present invention realizes digital precision control of system operation by accurately calculating the number of leaching tanks and the radial dimensions of the cylindrical tubes of the sedimentation tanks. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a plan view of an embodiment of a cyanide gold extraction system of the present invention;

[0051] Figure 2 It is a schematic elevation view of an embodiment of a cyanidation gold extraction system of the present invention;

[0052] Figure 3 This is a schematic diagram of the appearance of a leaching tank in an embodiment of a cyanide gold extraction system of the present invention;

[0053] Figure 4 It is a schematic diagram of the structure of the leaching tank of the embodiment of the cyanide gold extraction system of the present invention;

[0054] Figure 5 It is a top view schematic diagram of a seepage plate of an embodiment of a cyanide gold extraction system of the present invention;

[0055] Figure 6 It is a schematic diagram of the side view structure of the sedimentation tank of the embodiment of the cyanide gold extraction system of the present invention;

[0056] Figure 7 It is a schematic diagram of the top view of the sedimentation tank of the embodiment of the cyanide gold extraction system of the present invention;

[0057] Figure 8 It is a schematic diagram of the structure of the boiling pulping device of the embodiment of the cyanide gold extraction system of the present invention.

[0058] Description of reference numerals:

[0059] 100, leaching tank; 101, overflow pipe; 102, drainage pipe; 200, drainage ditch; 201, drainage plate; 300, seepage collection tank; 400, sedimentation tank; 401, cylindrical barrel; 402, conical barrel; 403, feeding barrel; 404, overflow trough; 500, sedimentation tank; 600, precious liquid tank; 700, lean liquid tank; 800, carbon adsorption tank; 900, bottom flow slurry pump; 1000, vertical submersible pump; 1100, precious liquid submersible pump; 1200, lean liquid submersible pump; 1300, boiling slurry making device; 1301, distributor; 1302, slurry making pipe; 1303, diagonal support; 1304, counterweight tank; 1305, fluid inlet pipe; 1400, sodium cyanide or environmental protection gold extraction agent solution addition pipe; 1500, lime solution addition pipe. DETAILED DESCRIPTION

[0060] In order to facilitate better understanding and implementation by those skilled in the art, the present invention is clearly and completely described below in conjunction with embodiments and application examples. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present invention.

[0061] like Figure 1 , Figure 2 , Figure 3 and Figure 4 The embodiment of the system of the present invention includes a leaching tank 100, a seepage collection tank 300, a sedimentation tank 500, a noble liquid tank 600, a lean liquid tank 700, a carbon adsorption tank 800 and a boiling pulping device 1300, and also includes Figure 6 and Figure 7 A settling tank 400 is shown.

[0062] The leaching tank 100 is composed of one or more, and five are used in this embodiment, and they operate independently of each other. The length of the leaching tank 100 is preferably 50.0m, the width is preferably 5.0m, the height is preferably 3.0m, the slope of the bottom of the tank is 1%, and the tank body is all above the ground surface. The side walls and the bottom of the leaching tank 100 are cast with reinforced concrete, and the bottom is treated for anti-seepage. In addition, an overflow pipe 101 and a drainage pipe 102 (the overflow pipe 101 is higher than the drainage pipe 102) are provided at different heights at the end of the leaching tank 100. Four drainage ditches 200 are provided at the bottom of each leaching tank 100; the drainage ditch is 50m long, 0.5m wide at the top, 0.4m wide at the bottom, and inward steps are formed on both sides 0.1m away from the top of the ditch, the ditch depth is 0.5m, the ditch spacing is 0.65m, and the slope is 1%; a drainage plate 201 is laid at the inward step of the drainage ditch 200.

[0063] like Figure 5 The drainage plate 201 is made of steel frame nylon material, length × width × height = 5.0 × 0.5 × 0.05m, and the drainage plate is arranged with 40 × 40mm square drainage holes, with a horizontal center spacing of 100mm and a vertical center spacing of 200mm. A layer of 400g / m 2 Concrete is poured between the geotextiles above the adjacent drainage ditches 200 and between the geotextiles and the wall of the leaching tank 100 in the longitudinal direction. The concrete and the upper surface of the geotextile have an impermeable layer as the bottom of the leaching tank 100 (i.e., the impermeable layer formed by the impermeable treatment of the bottom as mentioned above). A grab-type electric crane is provided above each leaching tank for loading and digging gold-containing ore and for hanging a boiling slurry making device during the leaching process. The leaching tank 100 has the dual functions of leaching gold-containing ore and solid-liquid separation.

[0064] The number of leaching tanks 100 is related to their own size, system processing capacity, ore pile specific gravity and leaching time, and the specific value is calculated and determined according to Formula 1.

[0065] Formula 1: ;

[0066] Where G is the number of leaching tanks, pieces;

[0067] K—redundancy coefficient, generally 1.05;

[0068] Q—daily processing volume, tons / day;

[0069] t—Leaching time determined by boiling slurry leaching test with aeration for 10 min, leaching solution for 20 min, and static immersion for 4.5 h, in hours;

[0070] a—length of leaching tank, m;

[0071] b—width of leaching tank, m;

[0072] c—thickness of the gold-bearing ore layer in the leaching tank, m;

[0073] ρ—Specific gravity of ore pile.

[0074] The seepage collection pool 300 is cast with reinforced concrete, located at the end of the leaching pool 100, preferably 5.0m wide and 1.0m deep below the ground surface, with a vertical submersible pump 1000 installed inside, and the bottom of the pool is treated for anti-seepage. The seepage collection pool 300 is used to collect the seepage liquid from the drainage ditch 200, and discharge the seepage liquid to the sedimentation tank 500 through the vertical submersible pump 1000.

[0075] Combination Figure 6 and Figure 7 The sedimentation tank 400 is made of galvanized canvas, and its upper part is a cylindrical cylinder 401 with an overflow trough 404 and a feeding cylinder 403, with a height of preferably 2.0m, part of which is above the ground surface and part of which is below the ground surface. The lower part of the sedimentation tank 400 is a conical cylinder 402, and the cone angle of the conical cylinder 402 is preferably 60°. The upper end of the conical cylinder 402 is connected to the lower end of the cylindrical cylinder 401, and the bottom end of the conical cylinder 402 is connected to the bottom flow slurry pump 900 through a discharge pipe. During the production process, after the leaching tank is boiled and slurried, the turbid liquid flows into the feeding cylinder 403 of the sedimentation tank 400 by gravity, and the suspended matter gradually settles into the conical cylinder 402 by its own weight. After reaching a certain concentration of slurry, it is discharged through the discharge pipe and the bottom flow slurry pump 900 and returned to the leaching tank 100. The upper clear liquid enters the overflow trough 404 and flows to the sedimentation tank 500 by gravity through the pipeline for subsequent treatment.

[0076] The diameter of the cylindrical tube 401 of the sedimentation tank 400 is related to the concentration of the input turbid liquid, the concentration of the underflow slurry, the processing capacity of the suspended matter, the sedimentation speed, the specific gravity and the number of leaching tanks, and is specifically calculated using Formula 2.

[0077] Formula 2: ;

[0078] In the formula φ —Diameter of the cylindrical tube of the sedimentation tank, m;

[0079] K0—safety factor, take 1.10;

[0080] G—Number of leaching tanks, pieces;

[0081] C1—mass concentration of turbid liquid fed into the sedimentation tank, %;

[0082] C2—mass concentration of underflow slurry discharged from the sedimentation tank, %;

[0083] ρ—true specific gravity of suspended matter;

[0084] S—the mass of suspended solids treated per unit area of ​​the sedimentation tank per unit time, t / (m 2 .h);

[0085] Where S = V P / (R1-R2);

[0086] R1—liquid-to-solid ratio when the concentration of turbid liquid fed into the sedimentation tank is C1;

[0087] R2—liquid-to-solid ratio when the concentration of underflow slurry discharged from the sedimentation tank is C2;

[0088] V P —The average settling velocity of suspended matter when a turbid liquid settles to the required underflow concentration, determined by sedimentation experiments, in m / h.

[0089] Note: Formula 2 is related to the number of leaching pools, but not to the size of the leaching pools. Because the boiling pulping device is operated in a continuous cycle, the amount of water in the boiling pulping device is constant regardless of the length, width, and thickness of the leaching pool; but each leaching pool has a separate boiling pulping device. The more leaching pools there are, the more boiling pulping devices there are, so the number of leaching pools will affect the total amount of water in the boiling pulping.

[0090] Still Figure 1 , the sedimentation tank 500 is generally composed of four sub-tanks, which are operated in series. The sedimentation tank 500 is excavated and constructed on site, with a length of 30.0m, a width of 10.0m and a depth of 5.0m. The side walls of the sedimentation tank 500 are cast with reinforced concrete, and the bottom is treated for anti-seepage. Overflow ports are provided between different sub-tanks. During normal production, the four sub-tanks are operated in series. When dredging is required (once every 0.5-1 year), the dredging can be stopped separately, and the other sub-tanks can be operated normally in series. The function of the sedimentation tank 500 is to purify the seepage at the bottom of the leaching tank 100, the upper drainage after the boiling slurry making in the leaching tank, and the sedimentation of the overflow of the sedimentation tank 400, and remove suspended matter in the liquid.

[0091] The precious liquid pool 600 is located at the end of the sedimentation tank 500, and its main functions are to hold precious liquid and secondary sedimentation. The precious liquid pool 600 is excavated on site, with a length of 12.5m, a width of 10.0m, and a depth of 5.0m. The side walls of the precious liquid pool 600 are cast with reinforced concrete, the bottom is treated for anti-seepage, a carbon adsorption tank 800 is provided on the top, and a precious liquid submersible pump 1100 is built in.

[0092] The barren liquid pool 700 is located on one side of the precious liquid pool 600 and is equipped with a barren liquid submersible pump 1200. Its main functions are: first, to contain barren liquid, sodium cyanide or environmentally friendly gold extracting agent and lime solution addition; second, the barren liquid submersible pump 1200 is used to supply barren liquid to the leaching pool 100. The barren liquid pool 700 is excavated on site, with a length of 12.5m, a width of 10.0m and a depth of 5.0m. The side walls of the barren liquid pool 700 are cast with reinforced concrete, and the bottom is treated for anti-seepage. There are sodium cyanide or environmentally friendly gold extracting agent solution addition pipes 1400 and lime solution addition pipes 1500 around it.

[0093] The carbon adsorption tank 800 is made of steel plate rolled and welded. It is cylindrical. The bottom plate is welded to the tank body, and the top plate is fastened with flanges, bolts, and rubber gaskets. A carbon adsorption chamber is set in the middle of the tank body. The bottom plate and top plate of the carbon adsorption chamber are made of perforated sieve plates. 102 layers of cotton sail filter cloth are laid on the top and bottom of the bottom plate to prevent carbon particles from passing through the sieve holes. Water flow channels and pipelines are left above and below the carbon adsorption chamber to achieve liquid in and out. The diameter of the carbon adsorption tank 800 is 1.0-2.0m and the height is 1.5-2.5m. Multiple can be set depending on the gold grade of the precious liquid. The carbon adsorption tank 800 is located above the precious liquid pool 600. During the production process, the supernatant of the precious liquid pool 600 is pumped to the water inlet of the first carbon adsorption tank by a precious liquid submersible pump 1100. The gold-containing precious liquid flows through each tank body in turn to complete carbon adsorption and finally discharged to the lean liquid pool 700. According to the gold grade of activated carbon in each carbon adsorption tank, the old carbon is regularly recovered and new carbon is loaded.

[0094] like Figure 8The boiling pulping device 1300 consists of a distributor 1301, a pulping pipe 1302 in the form of a galvanized pipe, a counterweight tank 1304, a fluid inlet pipe 1305 and an automatic coiler. The distributor 1301 is made of iron plate welding and is in the shape of a cuboid, with a length × width × height = 5.0 × 4.5 × 0.35 m; nine DN25mm pulping pipes 1302 are vertically welded at a spacing of 1.7 m at the bottom of the distributor 1301, each with a length of 3.0 m. The upper 1 / 3 of each pulping pipe 1302 is welded and fixed with a diagonal brace 1303 (20# round steel). In addition, the end of the pulping pipe 1302 is processed into a pointed head to facilitate insertion into the pulp layer. The upper part of the distributor 1301 is welded with a steel plate to form a counterweight tank with a length × width × height = 0.50 × 0.45 × 0.20, which is used to place the counterweight block to help the pulping pipe 1302 insert into the pulp layer. A DN50mm fluid inlet pipe 1305 is connected to one side of the long side of the distributor 1301. It is required to be a hose and fixed with an automatic hose reel. It can move back and forth along the leaching tank 100 with the boiling pulping device 1300. The end is used to connect the lean liquid supply pipeline of the lean liquid submersible pump 1200, the clean water supply pipeline of the clean water pump and the high-pressure gas supply pipeline of the air compressor. Different pipelines are respectively provided with control valves. Among them, the function of the lean liquid supply pipeline is to transport lean liquid to the leaching tank 100, the function of the air compressor high-pressure gas supply pipeline is to transport high-pressure gas to the distributor 1301, and the function of the clean water supply pipeline is to provide clean water for washing after all the boiling pulping operations are completed.

[0095] The production control method of the cyanidation gold extraction system of the present invention is as follows:

[0096] Step 1: Use an electric grab to load gold-containing ore raw materials into the leaching tank 100, and the surface is manually trimmed and flattened. The filling height of the gold-containing ore raw materials is required to be 2.0m (i.e., about two-thirds of the height of the leaching tank 100). The surface forms a 1% slope from the front end to the end of the leaching tank. The role of the slope is to facilitate the flow of liquid in the leaching tank 100 from the front end to the end, so that it can be smoothly discharged through the overflow pipe 101 or the drain pipe 102.

[0097] Step 2: Use the barren liquid submersible pump 1200 to inject barren liquid from the barren liquid pool 700 into the leaching pool 100, and the barren liquid is required to cover the highest point of the gold-containing ore raw material layer by more than 0.3 m.

[0098] Step 3: The electric crane hangs the boiling pulping device 1300 from the front end of the leaching tank 100 and starts boiling pulping in sections from front to back. During the boiling pulping process, the boiling pulping device 1300 is first filled with high-pressure air, and the electric crane hook slowly falls. Under the action of the counterweight and high-pressure air, the pulping pipe 1302 is inserted into the pulp layer to the bottom of the leaching tank 100. After the air is continuously filled for 10 minutes during the process, it is changed to fill the lean liquid in the lean liquid pool 700 for 20 minutes. After completion, the electric crane hook is slowly lifted and moved forward to carry out the next stage of boiling pulping. Each section of gold-containing ore raw material is subjected to boiling pulping for 0.5 hours, and then soaked for 4.5 hours in a continuous cycle until the leaching time requirement is met. During the leaching process, part of the liquid is discharged from the bottom of the leaching tank 100 through the drainage plate 201 and the drainage ditch 200, and then the seepage is discharged to the sedimentation tank 500 for purification through the vertical submersible pump 1000.

[0099] When the lean liquid is charged in the boiling pulping operation, the turbid liquid on the upper layer of the leaching tank 100 is discharged from the terminal overflow pipe 101 and flows into the sedimentation tank 400 by gravity through the feeding cylinder 403. After the turbid liquid is purified in the sedimentation tank 400, the overflow flows through the overflow tank 404 into the sedimentation tank 500 for secondary purification. When the concentration of the bottom flow suspended solids reaches more than 40%, it is discharged into the leaching tank where the leaching operation is completed for filtration and dehydration.

[0100] Step 4: After the boiling pulping operation in the leaching tank 100 is completed, the leaching tank 100 is left to stand until the supernatant is completely clarified, and the terminal drain pipe 102 is opened, and the supernatant is discharged into the sedimentation tank 500 by gravity.

[0101] After the gold-containing liquid is purified in the sedimentation tank 500 at four stages, it flows by gravity into the precious liquid tank 600. After the precious liquid is gold-recovered in the carbon adsorption tank 800, the barren liquid is discharged into the barren liquid tank 700.

[0102] During the production process, in order to meet the requirements of leaching chemical reactions, sodium cyanide or environmentally friendly gold extraction agent solution and lime solution need to be continuously added to the barren liquid pool 700 according to the consumption determined by production experience. The barren liquid supplemented with sodium cyanide or environmentally friendly gold extraction agent solution and lime solution is fed into the leaching pool 100 or the boiling pulping device 1300 through the barren liquid submersible pump 1200 for recycling.

[0103] The cyanide residue (gold-containing ore after leaching) in the leaching tank 100 is filtered by static filtration, and the internal liquid is discharged from the bottom of the leaching tank 100 through the drainage plate 201 and the drainage ditch 200. When the overall water content reaches below 20%, the cyanide residue is taken out by an electric grab. The system enters the next cycle operation.

[0104] Application Examples

[0105] A gold mine originally used the beneficiation process of crushing, grinding and flotation, and the gold concentrate produced was sold to the smelter for further processing; the tailings were discharged to the tailings pond for storage. Due to years of mining, the mine's resources have been exhausted. In order to extend the life of the enterprise, it was decided to recover the old tailings pond that had been closed and recover the residual gold in the tailings. The tailings pond has a stock of 2 million tons of tailings, with an average gold grade of 1.0g / t. The mine plans to recover and utilize 600 tons of tailings per day, operate 330 days a year, and can be recovered and utilized for 10 years. Since the tailings pond has been closed for a long time and the tailings are severely oxidized, the recovery rates of gravity separation and flotation processes are low; if the cyanide gold extraction process is used, the impact of tailings oxidation can be avoided and a higher recovery rate can be obtained. In view of this situation, the design institute commissioned by the mine uses existing technology to design the gold extraction system. The main equipment to be selected is as follows: 2 3.0×3.5m slurry mixing barrels; 12 5.0×5.5m aerated mechanical stirring leaching tanks; 2 3060 vibrating screens; 1 24m thickener; 225m 2 3 diaphragm filter presses; 6 slurry pumps; 2 Roots blowers; 2 clean water pumps. The main operating parameters are as follows: leaching time 16h; leaching concentration 40%; sodium cyanide concentration 1‰; slurry pH value 11-12. The laboratory conducted a cyanide leaching test on the ore samples of the mine, and the leaching rate was 90.0%. According to the design institute's plan, the mine's cyanide gold extraction system is expected to cover an area of ​​10,000m 2 The estimated investment is RMB 45 million. According to the equipment to be selected, the energy consumption of the cyanide gold extraction system built by the mine using existing technology is about 25.77 kwh / t, and there are 40 operators and maintenance personnel.

[0106] In view of the above situation, the mine adopted the short-process low-cost cyanidation gold extraction system of the present invention to replace the original design for tailings cyanidation gold extraction production under confidentiality conditions. The specific parameters are as follows: five leaching pools, located on the surface, each 50m long, 5.0m wide, 3.0m high, with a tailings layer filling thickness of 2.0m, containing four infiltration trenches; the seepage collection pool is constructed by surface excavation, 25m long, 5.0m wide, and 1.0m deep; the sedimentation tank is made of galvanized canvas material, semi-underground construction, the cylindrical tube is 2.0m high, 20m in diameter, the cone angle is 60°, and the cone is supported by the ground after excavation The bottom of the sedimentation tank is supported by a support, leaving space for the installation and operation of a slurry pump; the sedimentation tank adopts a four-stage sedimentation system, which is constructed by surface excavation, with each sub-tank being 15.0m long, 5.0m wide and 5.0m deep; the precious liquid tank is constructed by surface excavation, with a length of 12.5m, a width of 10.0m and a depth of 5.0m, and five groups of carbon adsorption tanks are arranged on the upper part; the lean liquid tank is constructed by surface excavation, with a length of 12.5m, a width of 10.0m and a depth of 5.0m, and is equipped with five submersible pumps; there are five groups of boiling slurry making devices.

[0107] 1.1 The number of leaching tanks is calculated according to the formula ;

[0108] Where G is the number of leaching tanks, pieces;

[0109] K—redundancy coefficient, 1.05;

[0110] Q—Daily processing capacity, 600 tons / day;

[0111] t—Leaching time determined by boiling slurry leaching test with aeration for 10 minutes, leaching solution for 20 minutes, and static immersion for 4.5 hours, 80 hours;

[0112] a—length of leaching tank, 50m;

[0113] b—Width of leaching tank, 5m;

[0114] c—Thickness of the gold-bearing ore layer in the leaching pool, 2m;

[0115] ρ—Specific gravity of ore pile, 1.3.

[0116] Calculation results: =4.85.

[0117] According to the calculation results, in order to ensure normal indicators during production fluctuations, the number of leaching tanks was determined to be five.

[0118] 1.2 The diameter of the sedimentation tank is based on the formula: ;

[0119] In the formula φ —Diameter of the cylindrical tube of the sedimentation tank, m;

[0120] K0—safety factor, take 1.10;

[0121] G—Number of leaching tanks, five;

[0122] C1—mass concentration of turbid liquid fed into the sedimentation tank, 10%;

[0123] C2—mass concentration of underflow slurry discharged from the sedimentation tank, 40%;

[0124] ρ—true specific gravity of suspended matter, 2.7;

[0125] S—the mass of suspended solids treated per unit area of ​​the sedimentation tank per unit time, t / (m 2 .h);

[0126] Where S = V P / (R1-R2);

[0127] R1—liquid-to-solid ratio when the concentration of turbid liquid fed into the sedimentation tank is C1, 9;

[0128] R2—liquid-to-solid ratio when the concentration of underflow slurry discharged from the sedimentation tank is C2, 1.5;

[0129] V P —The average settling velocity of suspended matter when the turbid liquid settles to the required underflow concentration, determined by sedimentation experiments, is 0.0996 m / h.

[0130] S=0.0996 / (9-1.5)=0.0133.

[0131] Calculation results: =19.66.

[0132] According to the calculation results, the diameter of the cylindrical tube of the sedimentation tank is determined to be 20m.

[0133] The mine uses the present invention to carry out cyanide gold extraction treatment on tailings in the tailings pond. According to statistics, the present invention is compared with the existing technology after construction and commissioning as follows: (1) The total investment of the system of the present invention is 10 million yuan, which reduces the investment cost by 78% compared with the existing technology; (2) The system of the present invention occupies an area of ​​5000m 2 , the surface area is reduced by 50% compared with the prior art; (3) the operating energy consumption of the system of the present invention is 5.82 kwh / t, which is 77% lower than that of the prior art; (4) the number of operating and maintenance personnel is reduced to 25, which reduces the labor cost by 38% compared with the prior art; (5) in terms of production indicators, the cyanide leaching rate reaches 90.2%, which is higher than the prior art indicators.

[0134] Although the present invention has been described in detail by reference to the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A short-process, low-cost cyanide gold extraction system, comprising a leaching tank (100), a settling tank (400), a sedimentation tank (500), a noble liquid tank (600) and a lean liquid tank (700), characterized in that: The leaching tank (100) is in the shape of a rectangular parallelepiped, and is provided with a drainage pipe (102) and an overflow pipe (101) located above the drainage pipe (102) at the end thereof; at least two drainage trenches (200) are provided below the leaching tank (100) along the length direction, and drainage devices are provided at the upper ends of the drainage trenches (200); the upper surface of the drainage device has an anti-seepage layer serving as the bottom surface of the leaching tank (100), and the bottom surface has a slope whose height gradually decreases from the head end to the tail end along the length direction; A boiling pulping device (1300) capable of changing position along the length direction of the leaching tank (100) is provided above the leaching tank (100); the boiling pulping device (1300) comprises a distributor (1301), the distributor (1301) being fixedly connected to a plurality of pulping pipes (1302) arranged longitudinally and used to be inserted into the material in the leaching tank (100) from top to bottom; a fluid inlet pipe (1305) in the form of a hose is connected to one side of the distributor (1301), The end of the fluid inlet pipe (1305) is used to connect to a lean liquid pipeline, a clean water pipeline or a high-pressure air pipeline; a crane is provided above the leaching tank (100) for loading the leaching tank (100) with gold-containing ore, digging the gold-containing ore from the leaching tank (100) and hanging the boiling pulping device (1300) during the leaching process; the end of the leaching tank (100) is connected to a seepage collection tank (300) whose bottom is lower than the seepage drainage ditch (200); the seepage collection tank (300) 00) is connected to the drainage ditch (200) and is internally provided with a vertical submersible pump (1000) for discharging the seepage liquid in the seepage liquid collection tank (300) to the sedimentation tank (500); the leaching tank (100) is arranged above the ground surface; the seepage liquid collection tank (300), the sedimentation tank (500), the precious liquid tank (600), and the lean liquid tank (700) are arranged below the ground surface; a part of the sedimentation tank (400) is above the ground surface, and another part is below the ground surface; The settling tank (400) is provided with an overflow trough (404) and a feeding cylinder (403), and is connected to an underflow slurry pump (900) at its bottom end; the feeding cylinder (403) is connected to the overflow pipe (101), so that the turbid liquid in the upper layer of the leaching tank (100) flows into the settling tank (400) through the overflow pipe (101) and the feeding cylinder (403) in sequence; the underflow slurry pump (900) is connected to the leaching tank (100) through a pipeline, so that the slurry settled in the settling tank (400) is discharged back to the leaching tank (100); the overflow trough (404) is connected to the sedimentation tank (500) through a pipeline, so that the clear liquid in the upper layer of the sedimentation tank (400) overflows into the sedimentation tank (500); the noble liquid tank (600) is connected to the sedimentation tank (500) The end of the precious liquid tank (500) is provided to facilitate the gold-containing liquid purified by the sedimentation tank (500) to flow into the precious liquid tank (600); a carbon adsorption tank (800) is provided above the precious liquid tank (600); a precious liquid submersible pump (1100) for extracting supernatant liquid from the precious liquid tank (600) is installed in the precious liquid tank (600); the water outlet end of the precious liquid submersible pump (1100) is connected to the water inlet of the carbon adsorption tank (800), and the water outlet of the carbon adsorption tank (800) is connected to the barren liquid tank (700) through a pipeline; a barren liquid submersible pump (1200) for transporting barren liquid to the leaching tank (100) is installed in the barren liquid tank (700); a sodium cyanide or environmentally friendly gold extraction agent solution addition pipe (1400) and a lime solution addition pipe (1500) are provided around the barren liquid tank (700).

2. The short-process low-cost cyanidation gold extraction system according to claim 1, characterized in that: There are more than two leaching tanks (100), which are arranged in parallel in the width direction and whose ends are connected to the same seepage collection tank (300).

3. The short-process low-cost cyanidation gold extraction system according to claim 1, characterized in that: The drainage device comprises a drainage plate (201) covering the drainage ditch (200) from the upper side, a geotextile is installed directly above the drainage plate (201), concrete is poured between the geotextiles above adjacent drainage ditches (200) and between the geotextiles and the wall of the leaching tank (100) in the length direction, and the anti-seepage layer is located on the upper surface of the concrete and the geotextile.

4. The short-process low-cost cyanidation gold extraction system according to claim 1, characterized in that: The top side of the distributor (1301) is provided with a counterweight groove (1304) for placing a counterweight block.

5. The short-process low-cost cyanidation gold extraction system according to claim 1, characterized in that: The sedimentation tank (500) is composed of multiple sub-tanks that are operated in series. Overflow ports are provided between the sub-tanks. During normal production, all sub-tanks are operated in series. When dredging is required, only one sub-tank is stopped for dredging, and the other sub-tanks are operated in series normally.

6. The short-process low-cost cyanidation gold extraction system according to any one of claims 1 to 5, characterized in that: The number of the leaching tanks (100) is determined by calculation according to the following formula: official: ; Where G is the number of leaching tanks, pieces; K—redundancy coefficient; Q—daily processing volume, tons / day; t—leaching time determined by boiling pulping leaching test, h; a—length of leaching tank, m; b—width of leaching tank, m; c—thickness of the gold-bearing ore layer in the leaching tank, m; ρ—Specific gravity of ore pile.

7. The short-process low-cost cyanidation gold extraction system according to any one of claims 1 to 5, characterized in that: The settling tank (400) comprises a cylindrical barrel (401) and a conical barrel (402); the overflow trough (404) is arranged on the upper part of the cylindrical barrel (401); the feeding barrel (403) is located directly above the cylindrical barrel (401); the lower end of the cylindrical barrel (401) is connected to the upper end of the conical barrel (402), and the bottom end of the conical barrel (402) is connected to the underflow slurry pump (900); the diameter of the cylindrical barrel (401) is calculated using the following formula: official: ; In the formula φ — diameter of cylindrical tube (401), m; K0—safety factor; G—Number of leaching tanks, pieces; C1—mass concentration of turbid liquid fed into the sedimentation tank (400), %; C2—mass concentration of underflow slurry discharged from sedimentation tank (400), %; ρ—true specific gravity of suspended matter in the sedimentation tank (400); S—mass of suspended solids treated per unit area per unit time in sedimentation tank (400), t / (m 2 .h), S=V P / (R1-R2); R1—liquid-to-solid ratio when the concentration of turbid liquid fed into the sedimentation tank is C1; R2—liquid-to-solid ratio when the concentration of underflow slurry discharged from the sedimentation tank is C2; V P —The average settling velocity of suspended matter when a turbid liquid settles to the required underflow concentration, determined by sedimentation experiments, in m / h.

8. A control method for a short-process, low-cost cyanidation gold extraction system according to any one of claims 1 to 7, characterized in that Here are the steps: Step 1: Use a grab bucket to load gold-containing ore raw materials into the leaching tank (100), trim and flatten the surface layer, and form a slope consistent with the anti-seepage layer of the leaching tank from the front end to the end of the leaching tank; Step 2: injecting lean solution into the leaching tank (100), requiring the lean solution to cover the highest point of the gold-containing ore raw material layer; Step 3: A boiling slurry making device (1300) is suspended by a crane and starts from the front end of the leaching tank (100) to perform boiling slurry making in sections from front to back; during the boiling slurry making process, the boiling slurry making device (1300) is first filled with high-pressure air, the crane hook is lowered, and the slurry making pipe (1302) is inserted into the slurry layer to the bottom of the leaching tank (100); after the high-pressure air is continuously filled in the process, the lean liquid is filled instead; after completion, the crane hook is lifted and moved forward to perform the next boiling slurry making; during the process, part of the liquid is discharged from the bottom of the leaching tank (100) through the drainage plate (201) and the drainage ditch (200), and then the seepage liquid is discharged to the sedimentation tank (500) for purification through the vertical submersible pump (1000); When the lean liquid is charged in the boiling pulping operation, the turbid liquid on the upper layer of the leaching tank (100) is discharged from the end overflow pipe (101) and flows into the sedimentation tank (400) through the feeding cylinder (403); after the turbid liquid is purified in the sedimentation tank (400), it overflows into the sedimentation tank (500) for secondary purification; when the concentration of the bottom flow suspended solids reaches more than 40%, it is discharged into the leaching tank where the leaching operation is completed for filtration and dehydration; Step 4: After the boiling slurrying operation in the leaching tank (100) is completed, the leaching tank is left to stand until the supernatant is completely clarified, and the drain pipe (102) is opened, and the supernatant is discharged by gravity into the sedimentation tank (500); the gold-containing liquid is purified in the sedimentation tank (500) and flows into the precious liquid tank (600); after the precious liquid recovers gold in the carbon adsorption tank (800), the barren liquid is discharged into the barren liquid tank (700); During the production process, in order to meet the requirements of the leaching chemical reaction, sodium cyanide or environmentally friendly gold extraction agent solution and lime solution need to be continuously added to the barren liquid pool (700) according to the consumption. The barren liquid added with sodium cyanide or environmentally friendly gold extraction agent solution and lime solution is fed into the leaching pool (100) or the boiling pulping device (1300) through the barren liquid submersible pump (1200) for recycling.

9. The control method of the short-process low-cost cyanidation gold extraction system according to claim 8, characterized in that: When the water content in the drainage ditch (200) reaches below 20%, the cyanide residue is removed by a grab bucket.

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