A negative pressure filtration type cyanide gold extraction system and its control method

Abstract

The present invention discloses a negative pressure suction filtration type cyanidation gold extraction system and its control method. A negative pressure chamber is provided below the leaching tank through a filter plate. The upper end of the connecting container of the negative pressure manufacturing device is connected to the negative pressure chamber, and the lower end is connected to the upper end of the L-shaped pipe. The upper end of the L-shaped pipe is connected with a water replenishing pipe and an exhaust pipe, and the lower end is successively connected with a water tank and a water pump. The water tank is equipped with a pneumatic communication pipe and a liquid level gauge. The bottom of the sub-water tank of the boiling pulping device is connected with a plurality of pulping pipes, and one side is connected with a fluid inlet pipe, and the end of the fluid inlet pipe is used to connect a lean liquid submersible pump, a clean water pump or an air compressor. A crane is provided above the leaching tank for loading and excavating gold-containing ore and hanging the boiling pulping device during the leaching process. The leaching efficiency and washing efficiency are improved, the moisture content of the cyanide residue is reduced; the investment cost of the cyanidation gold extraction system is reduced, the operation efficiency is improved, and the process indexes are improved.

Description

Technical Field

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

[0002] Cyanidation gold extraction mainly includes steps such as leaching, washing, carbon adsorption, and cyanide residue dehydration. Among them, leaching is a process of dissolving gold in an oxygen-containing cyanide (or environmentally friendly gold extraction agent) solution; washing is a process of reducing the gold ion concentration in the gold-containing solution after leaching; carbon adsorption is a process of adsorbing and recovering gold ions from the gold-containing solution that has completed cyanidation leaching using activated carbon; cyanide residue dehydration is a process of solid-liquid separation of cyanide residue and lean liquid. Cyanidation gold extraction involves influencing factors such as the state of gold particles, pulp concentration, cyanide (or environmentally friendly gold extraction agent) concentration, oxygen concentration, pH value, and leaching time.

[0003] Traditional cyanidation leaching devices are mechanical stirring leaching tanks, whose tank bodies are rolled and welded from steel plates, with a hollow shaft and a stirring impeller in the middle. The hollow shaft serves as an air inlet, and the impeller serves to stir the pulp. Traditional cyanidation washing devices are single-layer or multi-layer thickeners, which reduce the gold ion concentration in the gold-containing solution in the pulp through a countercurrent washing method to form rich liquid and lean liquid. Traditional cyanidation dehydration devices are filter presses, which inject the pulp into the filter chambers formed by adjacent filter plates through a slurry pump, apply pressure to discharge the water through the filter cloth, and the cyanide residue remains in the filter chamber to form a filter cake. The above-mentioned devices have high investment costs, long construction periods, large floor areas, low washing efficiency, and high moisture content of the cyanide residue filter cake, which have a certain impact on the operating cost and process indicators of the cyanidation gold extraction system. Summary of the Invention

[0004] The technical problems to be solved by the present invention are to provide a negative pressure suction filtration type cyanidation gold extraction system and a control method thereof. First, improve the leaching efficiency, while improving the solid-liquid separation effect, improving the washing efficiency, and reducing the moisture content of the cyanide residue; second, reduce the investment cost of the cyanidation gold extraction system, improve the operating efficiency, and improve the process indicators; third, obtain a higher ore processing capacity.

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

[0006] A negative pressure filtration cyanidation gold extraction system includes a sedimentation tank, a settling tank, a pregnant solution tank, a carbon adsorption device, and a barren solution tank. The system further includes one or more leaching tanks and a boiling pulping device corresponding to each leaching tank one by one. The leaching tank is provided with a drain pipe connecting to the settling tank and an overflow pipe connecting to the sedimentation tank. A negative pressure chamber is provided below the leaching tank through a filter plate. The system also includes a negative pressure generating device. The negative pressure generating device includes a connecting container and an L-shaped pipe. The upper end of the connecting container is connected to each negative pressure chamber through a negative pressure pipe, and the lower end is connected to the upper end of the L-shaped pipe. A water replenishing pipe and an exhaust pipe are connected to the upper end of the L-shaped pipe, and the lower end of the L-shaped pipe is connected to a water tank. The water tank is connected to a water pump driven by a variable frequency speed regulating motor through a water pump inlet pipe. An air pressure connecting pipe is installed at the upper end of the water tank. A liquid level gauge for sensing and measuring the water level in the water tank is also installed on the water tank and is located above the air pressure connecting pipe. The negative pressure generating device further includes a controller for collecting the water level data in the water tank through the liquid level gauge and for controlling the variable frequency speed regulating motor. The system also includes a boiling pulping device. The boiling pulping device includes a water distribution tank. The bottom of the water distribution tank is connected with several pulping pipes, and one side is connected with a fluid inlet pipe. The end of the fluid inlet pipe is used to connect to a barren solution submersible pump, a clean water pump, or an air compressor. A crane for loading and excavating gold-bearing ore and hanging the boiling pulping device during the leaching process is provided above each leaching tank.

[0007] Preferably, the number of the leaching tanks is determined according to Formula 1:

[0008] Formula 1:

[0009] In the formula, G - the number of leaching tanks, unit: piece;

[0010] K - a surplus coefficient, generally taking 1.1 - 1.2;

[0011] Q - the daily ore processing capacity, unit: ton / day;

[0012] t - the leaching time determined according to the boiling pulping leaching test, unit: h;

[0013] a - the length of the leaching tank, unit: m;

[0014] b - the width of the leaching tank, unit: m;

[0015] c - the thickness of the gold-bearing ore layer filled in the leaching tank, unit: m;

[0016] ρ - the bulk density of the ore, unit: t / m 3 。

[0017] Preferably, the diameter and height of the L-shaped pipe are determined according to Formula 2 and Formula 3:

[0018] Formula 2:

[0019] In the formula, φ - the diameter of the L-shaped pipe, unit: m;

[0020] K0 - Coefficient of surplus, generally taken as 1.1 - 1.2;

[0021] μ - Flow velocity of the liquid in the L-shaped pipe, generally designed to be 0.1 - 0.2 m / s;

[0022] V - Filtrate output of the leaching tank determined according to the negative pressure suction filtration experiment, m 3 / s;

[0023] Formula 3: H = K1hP(ρ0 / ρ);

[0024] Where H - Height difference from the lower edge of the exhaust pipe at the top of the L-shaped pipe to the highest liquid level in the water tank, m;

[0025] K1 - Coefficient of surplus, generally taken as 1.1 - 1.2;

[0026] h - Height of the clear water column that can be supported by ten standard atmospheres, taken as 103.4 m / Mpa;

[0027] P - Vacuum degree for the design requirements of the leaching tank, Mpa;

[0028] ρ0 - Density of clear water, t / m 3 ;

[0029] ρ - Density of the filtrate, t / m 3 。

[0030] Preferably, the upper part of the sedimentation tank is a cylindrical barrel with an overflow trough and a feeding cylinder, the lower part is a conical barrel, the bottom end of the conical barrel is connected with an underflow slurry pump through a discharge pipe, and this underflow slurry pump is connected to each leaching tank through a pipeline; the overflow trough is connected to the sedimentation tank through a clear liquid overflow pipe; the feeding cylinder is connected to the liquid discharge end of the overflow pipe.

[0031] More preferably, the diameter of the cylindrical barrel is calculated and determined according to Formula 4:

[0032] Formula 4:

[0033] Where φ - Diameter of the cylindrical barrel of the sedimentation tank, m;

[0034] K0 - Safety factor, generally taken as 1.1 - 1.2;

[0035] V1 - Output of the turbid liquid determined according to the boiling pulp-making leaching test, m 3 / h;

[0036] ρ1 - Density of the turbid liquid, t / m 3 ;

[0037] Where ρ1 = 100 / (C1 / ρ2 + 100 - C1)

[0038] C1 - Mass concentration of the turbid liquid fed into the settling pond, %;

[0039] C2 - Mass concentration of the underflow pulp discharged from the settling pond, %;

[0040] ρ2 - Density of suspended solids, t / m 3 ;

[0041] S - Mass of suspended solids processed per unit area of the settling pond per unit time, t / (m 2 .h);

[0042] where S = V P / (R1 - R2);

[0043] R1 - Liquid - solid ratio when the turbid liquid fed into the settling pond has a concentration of C1;

[0044] R2 - Liquid - solid ratio when the underflow pulp discharged from the settling pond has a concentration of C2;

[0045] V P - Average settling velocity of suspended solids under the condition that the turbid liquid settles to the required underflow concentration determined through settling experiments, m / h.

[0046] Preferably, the lean solution pond is located on one side of the pregnant solution pond; the lean solution pond is provided with a sodium cyanide or environmentally friendly gold extraction agent solution addition pipe and a lime solution addition pipe; a lean solution submersible pump for transporting the lean solution in the lean solution pond to the fluid inlet pipe is arranged in the lean solution pond; the pregnant solution pond is located at the end of the sedimentation pond; the carbon adsorption device is arranged above the pregnant solution pond; the water pump is connected to the sedimentation pond through a water pump drain pipe.

[0047] The control method of the negative - pressure suction filtration type cyanide gold extraction system,

[0048] Step 1: Use an electric grab bucket to load the gold - bearing ore raw materials into the leaching pond and trim and level them;

[0049] Step 2: Inject lean solution into the leaching pond, requiring the lean solution to submerge the gold - bearing ore raw material layer;

[0050] Step 3: Start the negative - pressure generating device, and use an electric crane to hang the boiling pulping device to carry out boiling pulping in sections from the front end to the rear end of the leaching pond; during the process, the boiling pulping device first fills high - pressure air through the fluid inlet pipe, the hook of the electric crane drops, the pulping pipe is inserted into the gold - bearing ore raw material layer, and after continuously filling air, it is changed to fill lean solution through the fluid inlet pipe;

[0051] Step 4: After the boiling pulping operation in the leaching pond ends, let it stand until the supernatant is completely clarified, open the drain pipe valve, and the supernatant flows into the sedimentation pond by gravity;

[0052] Step 5: After the above operations are completed, the cyanide residue in the leaching tank is further drained of the internal liquid through negative pressure suction filtration; when the overall moisture content reaches below 15%, an electric grab is used to remove the cyanide residue.

[0053] Furthermore, the specific control method of the negative pressure manufacturing device is as follows:

[0054] Step (1): Close the drain valve of the water tank and the water inlet valve of the water pump, and sequentially open the exhaust pipe valve, the air pressure connecting pipe valve, and the water replenishing pipe valve, and replenish lean liquid into the L-shaped pipe and the water tank through the water replenishing pipe;

[0055] Step (2): Close the air pressure connecting pipe valve when the air pressure connecting pipe starts to overflow; when the exhaust pipe starts to overflow, sequentially close the water replenishing pipe valve and the exhaust pipe valve;

[0056] Step (3): After the water replenishment is completed, sequentially start the water pump, open the water inlet valve of the water pump and the air pressure connecting pipe valve, part of the liquid in the leaching tank is drawn out through the filter plate, and then sequentially passes through the negative pressure pipe, the L-shaped pipe, the water tank, and is discharged to the sedimentation tank by the water pump;

[0057] During the negative pressure suction filtration operation, the operating frequency is adjusted in a timely manner through the liquid level detection data and the controller to control the drainage volume of the water pump, ensure that the liquid level in the water tank is within the set range, and thus obtain a continuous and stable vacuum negative pressure effect.

[0058] Compared with the prior art, the positive effects of the present invention are as follows: The system builds several leaching tanks in place, the interior is fully covered with gold-containing ore, and an alkaline cyanide-containing solution or an environmentally friendly gold extraction agent solution is injected to provide basic conditions for ore leaching. An overflow pipe and a liquid discharge pipe are arranged at the top of the leaching tank, and a negative pressure chamber is arranged at the bottom. The negative pressure chamber is connected to the negative pressure manufacturing device through a negative pressure pipe. Through the negative pressure manufacturing device, the lean liquid uniformly and quickly penetrates the gold ore raw material layer, improving the leaching efficiency, while improving the solid-liquid separation effect, improving the washing efficiency, and reducing the moisture content of the cyanide residue. The present invention excavates and constructs a sedimentation tank, a settling tank, a pregnant solution tank, and a lean liquid tank in place on one side of the leaching tank, and a carbon adsorption tank is arranged to realize the purification of the gold-containing liquid and the adsorption and recovery of gold ions. The cyanidation gold extraction system of the present invention can play roles such as leaching, washing, carbon adsorption, and cyanide residue dehydration, with low investment costs, short construction periods, high operating efficiency, excellent process indicators, and easy operation and control. In addition, the structures of the leaching tank, the settling tank, the sedimentation tank, etc. are simple and have large volumes, and a higher ore processing capacity can be obtained. Specifically as follows:

[0059] (1) The system of the present invention can replace a series of equipment and facilities such as leaching tanks, washing thickeners, decarbonization screens, and filter presses in the prior art. The construction costs of leaching ponds, negative pressure manufacturing devices, sedimentation ponds, settling ponds, rich liquid ponds, lean liquid ponds, etc. are mostly civil engineering investments, and can be constructed using idle mine shafts or mountain terrains in the mine. Under the same processing capacity, the investment can be reduced by about 70% compared with the prior art, and the floor area can be reduced by about 50%.

[0060] (2) Facilities such as the leaching pond of the present invention can play multiple roles, achieving multiple effects with one thing. The process flow is short, the equipment and facilities are concentrated, the production operation is simple, it is easy to realize production automation, and the number of on-site personnel can be reduced by 30 - 50%.

[0061] (3) The boiling pulp-making device in the present invention can continuously charge sodium cyanide or an environmentally friendly gold extraction agent, lime, and air into the leaching pond, and during the boiling pulp-making process, more sufficient dispersion contact of gold particles, sodium cyanide or an environmentally friendly gold extraction agent, and oxygen is achieved, which is more conducive to the efficient progress of the leaching chemical reaction.

[0062] (4) The negative pressure manufacturing device of the present invention can continuously perform negative pressure filtration on the liquid in the leaching pond. A large amount of liquid is forced to penetrate the ore layer and is discharged from the bottom filter plate, ensuring that the leaching reaction of each part of the gold-bearing ore raw material layer is more uniform and efficient.

[0063] (5) The present invention uses lean liquid for boiling pulp-making, and after the last boiling pulp-making is completed, negative pressure filtration operation can be continuously carried out for several hours. Based on this, the moisture content of the cyanide residue can be greatly reduced, the amount of gold-bearing liquid in the cyanide residue can be reduced, the dehydration time of the cyanide residue can be greatly shortened, and the operation efficiency can be improved. In addition, since the present invention processes the gold-bearing ore raw material in batches and intermittently, it can be sun-dried to reduce its moisture content. After the sun-drying operation, part of the clear water can be used for the last boiling pulp-making, and it can uniformly penetrate the gold-bearing ore raw material layer through negative pressure filtration, thereby further improving the washing effect and reducing the loss of valuable metals.

[0064] (6) During the production process of the present invention, the gold-bearing ore raw material is only loaded and dug before and after the start and end of the boiling pulp-making operation. The ore raw material is placed in the leaching pond at other times. The process operation only conveys and transfers the clarified liquid or the turbid liquid containing a small amount of suspended matter, and most of it can be self-flowed through the height difference of the facilities. The operation energy consumption is low, the equipment and facilities are lightly worn, and the operation cost can be reduced by more than 40% compared with the prior art under the same processing capacity.

[0065] (7) The whole set of system has a simple configuration, a short process flow, a low probability of running, leaking, dripping, and achieving water balance, no sewage discharge, and realizing intrinsic safety and environmental protection.

[0066] Generally speaking, adopting the system of the present invention can greatly simplify the equipment and facilities of the cyanide gold extraction process, save capital construction investment, reduce the floor area, reduce the number of operating personnel, lower the operation and maintenance costs, and has high production efficiency, excellent process indexes, and high application value and broad popularization prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a plan schematic diagram of an embodiment of the cyanide gold extraction system of the present invention;

[0068] Figure 2 It is an elevation schematic diagram of an embodiment of the cyanide gold extraction system of the present invention;

[0069] Figure 3 It is a front view structural schematic diagram of the leaching tank in an embodiment of the cyanide gold extraction system of the present invention;

[0070] Figure 4 It is a side view structural schematic diagram of the leaching tank in an embodiment of the cyanide gold extraction system of the present invention;

[0071] Figure 5 It is a structural schematic diagram of the settling tank in an embodiment of the cyanide gold extraction system of the present invention;

[0072] Figure 6 It is a structural schematic diagram of the carbon adsorption device in an embodiment of the cyanide gold extraction system of the present invention;

[0073] Figure 7 It is a structural schematic diagram of the boiling pulping device in an embodiment of the cyanide gold extraction system of the present invention;

[0074] Figure 8 It is an upper section structural schematic diagram of the negative pressure manufacturing device in an embodiment of the cyanide gold extraction system of the present invention;

[0075] Figure 9 It is a lower section structural schematic diagram of the negative pressure manufacturing device in an embodiment of the cyanide gold extraction system of the present invention.

[0076] Description of the reference numerals:

[0077] 1. Leaching tank; 1-1. Negative pressure chamber; 1-2. Filter plate; 1-3. Overflow pipe; 1-4. Drain pipe; 1-5. Drain pipe valve; 1-6. Negative pressure pipe; 1-7. Negative pressure pipe valve; 2. Negative pressure manufacturing device; 2-1. Connecting container; 2-2. Make-up water pipe; 2-2-1. Make-up water pipe valve; 2-3. Exhaust pipe; 2-3-1. Exhaust pipe valve; 2-4. L-shaped pipe; 2-5. Water tank; 2-5-1. Air pressure connecting pipe; 2-5-2. Air pressure connecting pipe valve; 2-5-3. Water tank drain pipe; 2-5-4. Water tank drain pipe valve; 2-6. Water pump; 2-6-1. Water pump inlet pipe; 2-6-2. Water pump inlet pipe valve; 2-6-3. Water pump drain pipe; 2-7. Liquid level gauge; 3. Settling tank; 3-1. Cylindrical barrel; 3-2. Conical barrel; 3-3. Feeding barrel; 3-4. Overflow trough; 3-5. Clear liquid overflow pipe; 3-6. Underflow slurry pump; 4. Sedimentation tank; 5. Rich liquid tank; 5-1. Rich liquid submersible pump; 6. Carbon adsorption device; 6-1. Inlet pipe; 6-2. Outlet pipe; 6-3. Carbon adsorption tank; 6-4. Bottom plate; 6-5. Top plate; 6-6. Water inlet channel; 6-7. Water outlet channel; 6-8. Lower sieve plate; 6-9. Upper sieve plate; 7. Lean liquid tank; 7-1. Lean liquid submersible pump; 8. Sodium cyanide or environmentally friendly gold extraction agent solution addition pipe; 9. Lime solution addition pipe; 10. Boiling pulping device; 10-1. Sub-water tank; 10-2. Pulping pipe; 10-3. Diagonal brace; 10-4. Counterweight trough; 10-5. Fluid inlet pipe. Detailed implementation manners

[0078] To enable those skilled in the art to better understand the present invention, the present invention will be further described below in conjunction with embodiments, drawings and on-site application situations. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0079] As Figures 1 to 4 , the embodiment of the cyanide gold extraction system of the present invention includes one or two or more (five in this embodiment) leaching tanks 1 arranged side by side and operating independently. The length of the leaching tank is preferably 50.0 m, the width is preferably 5.0 m, the height is preferably 3.0 m, the slope of the tank bottom is about 1%, and the whole tank body is on the ground surface. The side wall and bottom of the leaching tank are poured with reinforced concrete. In addition, a drain pipe 1-4 and an overflow pipe 1-3 higher than the drain pipe 1-4 are provided at the end of the leaching tank. A drain pipe valve 1-5 is installed on each branch pipeline between each leaching tank and the drain pipe 1-4.

[0080] There is a negative pressure chamber 1-1 below the leaching tank 1. The negative pressure chamber is 50 m long, 5.0 m wide, 0.5 m high, and has a slope of about 1%. The top of the negative pressure chamber is made of H-shaped steel to form a mesh support beam, and the support beam is fixed to the side wall of the leaching tank. A filter plate 1-2 is laid above the support beam. The filter plate is made of steel skeleton nylon material, with a length × width × height of 5.0 × 5.0 × 0.05 m. The filter plate is covered with 40×40 mm square drainage holes, with a transverse center spacing of 100 mm and a longitudinal center spacing of 200 mm. Two layers of 400 g / m 2 geotextile are laid above the filter plate. A grab-type electric crane is provided above each leaching tank, which is used for loading, excavating gold-bearing ore, and hanging the boiling pulp-making device during the leaching process. The leaching tank has multiple functions such as leaching, washing, and dewatering of gold-bearing ore.

[0081] The number of leaching tanks 1 is related to the size of the leaching tank, the ore processing capacity, the ore bulk density, the leaching time, etc. The specific value is determined according to Formula 1.

[0082] Formula 1:

[0083] Where G - the number of leaching tanks, units;

[0084] K - surplus coefficient, generally taking 1.1 - 1.2;

[0085] Q - daily ore processing capacity, tons per day;

[0086] t - leaching time determined according to the boiling pulp-making leaching test, h;

[0087] a - length of the leaching tank, m;

[0088] b - width of the leaching tank, m;

[0089] c - thickness of the gold-bearing ore layer filled in the leaching tank, m;

[0090] ρ - ore bulk density, t / m 3 .

[0091] The embodiment of the cyanidation gold extraction system of the present invention further includes a set of negative pressure manufacturing device 2. Combined with Figure 1 、 Figure 2 、 Figure 3 、 Figure 8 and Figure 9, the negative pressure manufacturing device 2 is entirely located below the ground surface. It includes a connection container 2-1 and an L-shaped pipe 2-4. The longitudinal section of the L-shaped pipe 2-4 is perpendicular to the horizontal plane, and the transverse section is parallel to the horizontal plane. The upper end of the connection container 2-1 is connected to each negative pressure chamber 1-1 through a negative pressure pipe 1-6. A negative pressure pipe valve 1-7 is installed on the branch pipeline between the negative pressure pipe 1-6 and each negative pressure chamber 1-1. The lower end of the connection container 2-1 is connected to the upper end of the longitudinal section of the L-shaped pipe 2-4. A water replenishing pipe 2-2 with a water replenishing pipe valve 2-2-1 and an exhaust pipe 2-3 with an exhaust pipe valve 2-3-1 are connected to the upper end of the longitudinal section of the L-shaped pipe 2-4. The outer end of the transverse section of the L-shaped pipe 2-4 is connected to a water tank 2-5.

[0092] The water tank 2-5 is connected to a water pump 2-6 through a water pump inlet pipe 2-6-1 with a water pump inlet pipe valve 2-6-2. The water pump 2-6 is connected to a water pump drain pipe 2-6-3. The other end of the water pump drain pipe 2-6-3 is connected to a sedimentation tank 4.

[0093] Among them, the water pump 2-6 uses a variable frequency speed regulation motor. An air pressure connecting pipe 2-5-1 with an air pressure connecting pipe valve 2-5-2 is installed at the upper end of the water tank 2-5. The air pressure connecting pipe 2-5-1 is vertically arranged. A liquid level gauge 2-7 for sensing and measuring the water level in the water tank 2-5 is also installed on the water tank 2-5 directly above the air pressure connecting pipe 2-5-1. The liquid level gauge 2-7 is generally a radar liquid level gauge, a laser liquid level gauge or an ultrasonic liquid level gauge. A water tank drain pipe 2-5-3 with a water tank drain pipe valve 2-5-4 is also connected to the bottom side or the lower end of the water tank 2-5.

[0094] The embodiment of the system of the present invention further includes a controller for collecting the water level data in the water tank 2-5 through the liquid level gauge 2-7 and for controlling the variable frequency speed regulation motor.

[0095] The diameter and height of the L-shaped pipe are related to the filtrate production in the leaching tank and the designed negative pressure intensity. The specific values are determined according to Formulas 2 and 3.

[0096] Formula 2:

[0097] Where φ - the diameter of the L-shaped pipe, m;

[0098] K0 - the surplus coefficient, generally taking 1.1 - 1.2;

[0099] μ - the flow rate of the liquid in the L-shaped pipe, generally designed to be 0.1 - 0.2 m / s;

[0100] V - the filtrate production in the leaching tank determined according to the negative pressure suction filtration experiment, m 3 / s.

[0101] Formula 3: H = K1hP(ρ0 / ρ);

[0102] Where H is the height difference from the lower edge of the exhaust pipe at the top of the L-shaped pipe to the highest liquid level of the water tank, in m;

[0103] K1 is the safety factor, generally taken as 1.1 - 1.2;

[0104] h is the height of the clear water column that can be supported by ten standard atmospheres, taken as 103.4 m / Mpa;

[0105] P is the vacuum degree according to the design requirements of the leaching tank, in Mpa;

[0106] ρ0 is the density of clear water, t / m 3 ;

[0107] ρ is the density of the filtrate, t / m 3 .

[0108] The embodiment of the cyanide gold extraction system of the present invention further includes a sedimentation tank 3, a settling pond 4, a pregnant solution pond 5, a set of carbon adsorption device 6, a barren solution pond 7, and five sets (the number corresponds to that of the leaching tank 1) of boiling pulp-making devices 10. The overflow end of the overflow pipe 1-3 is connected to the sedimentation tank 3. The drain end of the drain pipe 1-4 is connected to the settling pond 4.

[0109] Such as Figure 7 , the boiling pulp-making device 10 is composed of a water distribution tank 10-1, a pulp-making pipe 10-2 in the form of a galvanized pipe, a counterweight tank 10-4, a fluid inlet pipe 10-5, and an automatic coil winder. Among them, the water distribution tank 10-1 is made by welding iron plates and is in the shape of a cuboid, with length × width × height = 5.0 × 4.5 × 0.35 m; nine DN25mm pulp-making pipes 10-2 are vertically welded to the bottom of the water distribution tank 10-1 at a spacing of 1.7 m, and each pipe has a length of 3.0 m. The upper 1 / 3 of each pulp-making pipe 10-2 is welded and fixed with a diagonal brace 10-3 (20# round steel). In addition, the end of the pulp-making pipe 10-2 is processed into a pointed head for easy insertion into the pulp layer. The upper part of the water distribution tank 10-1 is welded with a steel plate to form a counterweight tank 10-4 with length × width × height = 0.50 × 0.45 × 0.20 for placing counterweight blocks to help the pulp-making pipe 10-2 insert into the pulp layer. One side of the long side of the water distribution tank 10-1 is connected with a DN50mm fluid inlet pipe 10-5, which is required to be a flexible pipe and is fixed with an automatic coil winder. It can reciprocate along the leaching tank 1 with the boiling pulp-making device 10. The end is used to connect the barren solution supply pipeline of the barren solution submersible pump 7-1, the clear water supply pipeline of the clear water pump, or the high-pressure gas supply pipeline of the air compressor. Different pipelines are respectively provided with control valves. Among them, the function of the barren solution supply pipeline is to transport barren solution to the leaching tank 1, the function of the high-pressure gas supply pipeline of the air compressor is to transport high-pressure gas to the water distribution tank 10-1, and the function of the clear water supply pipeline is to provide clear water for washing after all the boiling pulp-making operations are completed.

[0110] As Figure 5 , the sedimentation tank 3 is made of galvanized canvas. Its upper part is a cylindrical barrel 3-1 with an overflow trough 3-4 and a feed cylinder 3-3. The height is preferably 2.0 m, with part above the ground and part below the ground. The lower part of the sedimentation tank 3 is a conical barrel 3-2. The cone angle of the conical barrel 3-2 is preferably 60°. The upper end of the conical barrel 3-2 is connected to the lower end of the cylindrical barrel 3-1. The bottom end of the conical barrel 3-2 is connected with an underflow slurry pump 3-6 through a discharge pipe. The underflow slurry pump 3-6 is connected to each leaching tank 1 through a pipeline. The overflow trough 3-4 is connected to the sedimentation tank 4 through a clear liquid overflow pipe 3-5.

[0111] The diameter (inner diameter) of the cylindrical barrel 3-1 of the sedimentation tank 3 is related to the volume and concentration of the incoming turbid liquid, the underflow pulp concentration, the sedimentation rate, the density of suspended solids, etc., and is specifically calculated using formula 4.

[0112] Formula 4:

[0113] In the formula, φ - the diameter of the cylindrical barrel of the sedimentation tank, m;

[0114] K0 - safety factor, generally taken as 1.1 - 1.2;

[0115] V1 - the output of the turbid liquid determined according to the boiling pulp-making leaching test, m 3 / h;

[0116] ρ1 - the density of the turbid liquid, t / m 3 ;

[0117] where ρ1 = 100 / (C1 / ρ2 + 100 - C1)

[0118] C1 - the mass concentration of the turbid liquid fed into the sedimentation tank, %;

[0119] C2 - the mass concentration of the underflow pulp discharged from the sedimentation tank, %;

[0120] ρ2 - the density of suspended solids, t / m 3 ;

[0121] S - the mass of suspended solids processed per unit area of the sedimentation tank per unit time, t / (m 2 .h);

[0122] where S = V P / (R1 - R2)

[0123] R1 - the liquid-solid ratio when the concentration of the turbid liquid fed into the sedimentation tank is C1;

[0124] R2 - the liquid-solid ratio when the concentration of the underflow pulp discharged from the sedimentation tank is C2;

[0125] VP - The average sedimentation velocity of suspended solids in the turbid liquid sedimented to the required underflow concentration condition determined by the sedimentation experiment, m / h.

[0126] Still as Figure 1 , the sedimentation tank 4 is generally composed of four - stage sub - tanks and operates in series. The sedimentation tank is excavated on - site. It is advisable that the length is 25.0 m, the width is 10.0 m, and the depth is 5.0 m. The side walls and bottom of the sedimentation tank 4 are poured with reinforced concrete. There are overflow ports between different sub - tanks. During normal production, the four sub - tanks operate in series. When dredging is required (once every 0.5 - 1 year), a single sub - tank can be stopped for dredging alone, and the other sub - tanks operate in series normally. The sedimentation tank 4 is mainly used for the precipitation purification of the bottom filtrate of the leaching tank, the upper drainage after the boiling pulp making in the leaching tank, and the overflow of the sedimentation tank, to remove suspended solids in the liquid.

[0127] The negative - pressure manufacturing device 2 utilizes the local vacuum generated by the liquid height difference at both ends of the L - shaped pipe 2 - 4 and the action of the atmospheric pressure to form a negative pressure at the connecting container 2 - 1. Since the connecting container 2 - 1 is connected to the negative - pressure chamber 1 - 1 below the leaching tank 1 through the negative - pressure pipe 1 - 6, a suction filtration effect is formed on the liquid in the negative - pressure chamber 1 - 1. After the liquid is drawn out by the filter plate 1 - 2, it successively enters the connecting container 2 - 1, the L - shaped pipe 2 - 4, the water tank 2 - 5 along the negative - pressure pipe 1 - 6, and finally is discharged to the sedimentation tank 4 by the water pump 2 - 6.

[0128] The pregnant - solution tank 5 is located at the end of the sedimentation tank 4, and its main function is to hold the pregnant solution and perform secondary precipitation. A pregnant - solution submersible pump 5 - 1 is installed in the pregnant - solution tank 5.

[0129] Combined with Figure 6 , the carbon adsorption device 6 includes a tank body with a top plate 6 - 5 at the upper end and a bottom plate 6 - 4 at the lower end. An upper sieve plate 6 - 9 and a lower sieve plate 6 - 8 are arranged in the tank body. The space between the upper sieve plate 6 - 9 and the lower sieve plate 6 - 8 is the carbon adsorption chamber 6 - 3, and the carbon adsorption chamber 6 - 3 is filled with activated carbon particles. There is an outlet channel 6 - 7 between the top plate 6 - 5 and the upper sieve plate 6 - 9, and the outlet channel 6 - 7 is connected to an outlet pipe 6 - 2. There is an inlet channel 6 - 6 between the bottom plate 6 - 4 and the lower sieve plate 6 - 8, and the inlet channel 6 - 6 is connected to an inlet pipe 6 - 1. Further, one or two layers of cotton sail filter cloth are respectively laid on the upper side of the bottom plate 6 - 4 and the lower side of the top plate 6 - 5 to prevent carbon particles from being discharged through the sieve holes and to play a role in filtering and purifying the water quality, further improving the carbon adsorption effect.

[0130] The carbon adsorption device 6 of this embodiment has five tanks. The water outlet pipe 6-2 of the previous-stage tank is connected to the water inlet pipe 6-1 of the adjacent subsequent-stage tank. The water inlet pipe 6-1 of the first-stage tank is connected to the pregnant solution submersible pump 5-1 through a pipeline. The water outlet pipe 6-2 of the last-stage carbon adsorption tank communicates with the barren solution pond 7. The pregnant solution containing gold is supplied to the carbon adsorption device 6 by the pregnant solution submersible pump 5-1, and the barren solution is discharged into the barren solution pond 7 through the water outlet pipe 6-2 of the last-stage tank, realizing the cyclic adsorption of gold.

[0131] The tank is made by rolling and welding steel plates, and is cylindrical. The bottom plate 6-4 is welded to the tank body, and the top plate 6-5 is fastened with flanges, bolts, and rubber gasket seals; there are water flow channels and pipelines left above and below the carbon adsorption tank to realize the entry and exit of liquid. The diameter of the tank is 1.0 - 2.0 m, and the height is 1.5 - 2.5 m. Multiple tanks can be set according to the gold grade of the pregnant solution.

[0132] The barren solution pond 7 is located on one side of the pregnant solution pond 5. Its main functions are to hold the barren solution, add sodium cyanide (or environmentally friendly gold extraction agent) and lime solution, place a submersible pump to supply the barren solution to the leaching tank, and place a submersible pump to fill water into the negative pressure manufacturing device. The barren solution pond 7 is excavated and constructed on the spot. It is appropriate to have a length of 12.5 m, a width of 10.0 m, and a depth of 5.0 m. The side walls and bottom of the barren solution pond 7 are poured with reinforced concrete, and there are sodium cyanide or environmentally friendly gold extraction agent solution addition pipes 8 and lime solution addition pipes 9 around it.

[0133] A barren solution submersible pump 7-1 is arranged in the barren solution pond 7. This barren solution submersible pump 7-1 is used to transport the barren solution in the barren solution pond 7 to the fluid inlet pipe 10-5.

[0134] The pregnant solution pond 5 is located at the end of the sedimentation pond. The pregnant solution pond 5 is excavated and constructed on the spot. It is appropriate to have a length of 12.5 m, a width of 10.0 m, and a depth of 5.0 m. The side walls and bottom of the pregnant solution pond 5 are poured with reinforced concrete, and the carbon adsorption device 6 is arranged above the pregnant solution pond 5.

[0135] The production control method of the cyanide gold extraction system of the present invention is as follows:

[0136] Step 1: Use an electric grab bucket to load the gold-containing ore raw materials into the leaching tank 1, and the surface layer is manually trimmed and leveled. It is required that the loading height of the gold-containing ore raw materials is 2.0 m, and the surface layer forms a slope of about 1% from the front end to the end of the leaching tank 1.

[0137] Step 2: Inject the barren solution into the leaching tank, and it is required that the barren solution is 0.3 m above the highest point of the gold-containing ore raw material layer.

[0138] Step 3: Start the negative pressure manufacturing device 2, and use an electric crane to hang the boiling pulp-making device 10 to carry out boiling pulp-making in sections from the front end to the rear end of the leaching tank 1. During the process, the boiling pulp-making device 10 is first filled with high-pressure air through the fluid inlet pipe 10-5. The hook of the electric crane slowly descends. Under the action of the counterweight and high-pressure air, the pulp-making pipe 10-2 is inserted into the pulp layer to the bottom of the leaching tank 1. After continuously filling air for 10 minutes during the process, it is changed to fill the lean liquid through the fluid inlet pipe 10-5 for 20 minutes. After completion, the hook of the electric crane is slowly lifted and moved forward to carry out the next section of boiling pulp-making. Each section of gold-bearing ore raw material is continuously circulated according to 0.5 hours of boiling pulp-making and 4.5 hours of static soaking until the leaching time requirement is met.

[0139] The turbid liquid on the upper layer of the leaching tank flows into the feeding cylinder 3-3 of the sedimentation tank 3 by gravity through the overflow pipe 1-3. After the turbid liquid is purified in the sedimentation tank 3, the suspended matter gradually settles by its own weight and enters the conical cylinder 3-2. When the bottom flow suspended matter concentration reaches more than 40%, it is discharged outside through the bottom flow slurry pump 3-6 and returned to the leaching tank 1. The upper layer of clear liquid enters the overflow tank 3-4 and flows into the sedimentation tank 4 by gravity through the clear liquid overflow pipe 3-5 for subsequent treatment. When the liquid level is too high due to the filling of the lean liquid during the boiling pulp-making operation, the excess turbid liquid on the upper layer of the leaching tank 1 is discharged from the overflow pipe 1-3 and flows into the sedimentation tank 3 by gravity.

[0140] Step 4: After the boiling pulp-making operation in the leaching tank 1 is completed, let it stand until the supernatant is completely clarified. Open the valve of the drain pipe 1-5, and the supernatant flows into the sedimentation tank 4 by gravity.

[0141] After the gold-bearing liquid is purified in four stages in the sedimentation tank 4, it flows into the pregnant solution tank 5 by gravity. After the gold in the pregnant solution is recovered by the carbon adsorption device 6, the lean liquid is discharged into the lean liquid tank 7. Add sodium cyanide (or environmentally friendly gold extraction agent) solution and lime solution into the lean liquid tank 7. After restoring to the required reagent concentration and pH value, it is fed into the leaching tank 1 and the boiling pulp-making device 10 by the lean liquid submersible pump 7-1 for recycling.

[0142] Step 5: After the above operations are completed, the cyanide residue (gold-bearing ore after leaching) in the leaching tank is further subjected to negative pressure filtration for several hours, and most of the internal liquid is discharged through the negative pressure manufacturing device. When the overall moisture content reaches below 15%, use an electric grab to take out the cyanide residue. The system enters the next cycle operation.

[0143] Among them, the specific control method of the negative pressure manufacturing device 2 is as follows:

[0144] Step (1): Close the valve 2-5-4 of the water tank drain pipe and the valve 2-6-2 of the water pump inlet pipe, and sequentially open the valve 2-3-1 of the exhaust pipe, the valve 2-5-2 of the air pressure connecting pipe, and the valve 2-2-1 of the water replenishing pipe. Add lean liquid to the L-shaped pipe 2-4 and the water tank 2-5 through the water replenishing pipe 2-2;

[0145] Step (2): When the air pressure connecting pipe 2-5-1 starts to overflow, close the air pressure connecting pipe valve 2-5-2; when the exhaust pipe 2-3 starts to overflow, close the make-up water pipe valve 2-2-1 and the exhaust pipe valve 2-3-1 in sequence.

[0146] Complete the water replenishment operation into the L-shaped pipe 2-4 and the water tank 2-5 through Step (1) and Step (2).

[0147] Step (3): After the water replenishment is completed, start the water pump 2-6 in sequence, open the water pump inlet pipe valve 2-6-2 and the air pressure connecting pipe valve 2-5-2. At this time, a vacuum negative pressure is formed inside the connecting container 2-1. After opening the negative pressure pipe valve 1-7, the leaching tank 1 connected thereto starts to discharge the filtrate. Part of the liquid in the leaching tank 1 passes through the filter plate 1-2 and is extracted, and then passes through the negative pressure pipe 1-6, the L-shaped pipe 2-4, the water tank 2-5 in sequence, and finally is discharged to the sedimentation tank 4 by the water pump 2-6.

[0148] During the negative pressure filtration operation, the running frequency of the variable frequency speed regulating motor is adjusted timely through the detection data of the liquid level gauge 2-7 and the controller, and the drainage volume of the water pump 2-6 is reasonably controlled to ensure that the liquid level in the water tank 2-5 is within a certain set range (for example, the liquid level in the water tank is not lower than the upper edge of the horizontal section of the L-shaped pipe and not lower than the upper edge of the water pump inlet pipe), so as to obtain a continuous and stable vacuum negative pressure effect.

[0149] Embodiment

[0150] A certain gold mine originally adopted the beneficiation process of crushing, grinding, and flotation, and the tailings were discharged to the tailings pond for stacking. With the continuous rise of the gold price, the mine decided to recover the old tailings pond that had been closed and recover the residual gold in the tailings. The tailings inventory in this tailings pond is 4 million tons, and the average gold grade is 0.9 g / t. The mine plans to recover and utilize the tailings at a rate of 600 t / d, operate for 330 days a year, and can be recovered and utilized for 12 years. Since the tailings pond has been closed for a long time and the tailings are severely oxidized, the recovery rates of the gravity separation and flotation processes are both low; if the cyanidation gold extraction process is adopted, the influence of tailings oxidation can be avoided, a higher recovery rate can be obtained, and the economic feasibility of the tailings pond recovery can be ensured. In view of this situation, the design institute entrusted by the mine designed the gold extraction system using existing technologies, and the main equipment to be selected is as follows: 2 sets of 4.0×4.5 m pulp mixing tanks; 10 sets of 7.0×7.5 m pneumatic mechanical agitation leaching tanks; 2 sets of 3060 vibrating screens; 1 set of 32-meter thickener; 225 m 25 diaphragm filter presses; 6 slurry pumps; 2 Roots blowers; 2 water pumps. The main operating parameters are as follows: leaching time 24 h; leaching concentration 40%; sodium cyanide concentration 1‰; pulp pH value 11 - 12. The laboratory conducted cyanide leaching tests on the ore samples of this mine, with a leaching rate of 90.2%, a washing rate of 88.1%, and a moisture content of cyanide residue of 15%. According to the design institute's plan, the cyanide gold extraction system of this mine is expected to cover an area of 11,000 m 2 , and the estimated investment is 60 million yuan. According to the equipment to be selected, the energy consumption of the cyanide gold extraction system built by this mine using existing technology is about 24.63 kwh / t, and there are 50 operation and maintenance personnel.

[0151] In view of the above situation, this mine uses a negative pressure suction filtration type cyanide gold extraction system of the present invention to replace the original design for tailings cyanide gold extraction operations under confidentiality conditions. The specific parameters are as follows: 5 leaching ponds, located on the ground surface, with a length of 50 m, a width of 5.0 m, and a height of 3.0 m. The supporting negative pressure chamber has a length of 50 m, a width of 5.0 m, and a height of 0.5 m. The thickness of the gold-bearing tailings raw material layer in the leaching pond is 2.0 m; the negative pressure manufacturing device is built using an idle vertical shaft. The negative pressure auxiliary generating pipe is a seamless steel pipe with a model of 480×12 mm, and the height difference between the water supply pipe at the top of the auxiliary pipe and the water tank liquid level is 30 m; the sedimentation pond is made of galvanized canvas, built semi-underground, with a cylindrical barrel height of 2.0 m and a diameter of 15 m, and the included angle of the conical body is 60°. The conical body is supported by the ground after excavation, and there is a space for installing and operating the slurry pump at the bottom; the sedimentation pond adopts 4-stage sedimentation, excavated and built on the ground surface. Each sub-pond has a length of 12.5 m, a width of 5.0 m, and a depth of 5.0 m; the pregnant solution pond is excavated and built on the ground surface, with a length of 12.5 m, a width of 10.0 m, and a depth of 5.0 m. Five groups of carbon adsorption tanks are set on the upper part; the barren solution pond is excavated and built on the ground surface, with a length of 12.5 m, a width of 10.0 m, and a depth of 5.0 m. There are 6 submersible pumps; 5 groups of boiling pulp-making devices.

[0152] 1.1 Number of leaching ponds According to the formula:

[0153] In the formula, G - number of leaching ponds, unit: piece; K - surplus coefficient, taking 1.1; Q - daily ore treatment volume, 1000 tons / day; t - leaching time determined according to the boiling pulp-making leaching test, 45 h; a - length of the leaching pond, 50 m; b - width of the leaching pond, 5 m; c - thickness of the gold-bearing tailings filling layer in the leaching pond, 2.0 m; ρ - tailings bulk density, 1.6 t / m 3 .

[0154] Calculation result:

[0155] According to the calculation result, the number of leaching ponds is determined to be five.

[0156] 1.2 Diameter of L-shaped pipe According to the formula:

[0157] In the formula, φ is the diameter of the L-shaped pipe, in m; K0 is the surplus coefficient, taken as 1.2; μ is the flow velocity of the liquid in the L-shaped pipe, designed to be 0.15 m / s; V is the filtrate output of the leaching tank determined according to the negative pressure suction filtration experiment, 0.017 m 3 / s.

[0158] Calculation result:

[0159] According to the calculation result, the inner diameter of the L-shaped pipe is determined to be 456 mm, and it is made of a standard seamless steel pipe of 480×12 mm.

[0160] 1.3 The height of the L-shaped pipe is calculated according to the formula: H = K1hP(ρ0 / ρ);

[0161] In the formula, H is the height difference from the lower edge of the exhaust pipe at the top of the L-shaped pipe to the highest liquid level of the water tank, in m; K1 is the surplus coefficient, taken as 1.2; h is the height of the clear water column that can be supported by ten standard atmospheric pressures, taken as 103.4 m / Mpa; P is the vacuum degree required for the design of the leaching tank, 0.25 Mpa; ρ0 is the density of clear water, 1.00 t / m 3 ; ρ is the density of the filtrate, 1.02 t / m 3 .

[0162] Calculation result: H = 1.2×103.4×0.25×(1.00 / 1.02) = 30.41 m.

[0163] According to the calculation result, the height difference from the lower edge of the exhaust pipe at the top of the L-shaped pipe to the highest liquid level of the water tank is determined to be 30 m.

[0164] 1.4 The diameter of the sedimentation tank is calculated according to the formula:

[0165] In the formula, φ is the diameter of the cylindrical barrel of the sedimentation tank, in m; K0 is the safety factor, taken as 1.1; V1 is the output of the turbid liquid determined according to the boiling pulp-making leaching test, 12.24 m 3 / h; ρ1 is the density of the turbid liquid, t / m 3 ; where ρ1 = 100 / (C1 / ρ2 + 100 - C1), in the formula, C1 is the mass concentration of the turbid liquid fed into the sedimentation tank, 10%; C2 is the mass concentration of the underflow pulp discharged from the sedimentation tank, 40%; ρ2 is the density of the suspended matter, 3.0 t / m 3 ; calculating ρ1 is 1.07 t / m 3 ; S is the mass of the suspended matter processed per unit area of the sedimentation tank per unit time, t / (m 2 .h); where S = V P / (R1 - R2), in the formula, R1 is the liquid-solid ratio when the turbid liquid fed into the sedimentation tank has a concentration of C1, 9:1; R2 is the liquid-solid ratio when the underflow pulp discharged from the sedimentation tank has a concentration of C2, 3∶2; VP - The average sedimentation velocity of suspended solids when the turbid liquid settles to the required underflow concentration condition determined by the sedimentation experiment is 0.0722 m / h; the calculated S is 0.00963 t / (m 2 .h).

[0166] Calculation result:

[0167] According to the calculation result, the diameter of the cylindrical barrel of the sedimentation tank is determined to be 15 m.

[0168] This mine uses the present invention to carry out cyanidation gold extraction treatment on the tailings in the tailings pond. According to statistics, the comparison between the present invention after construction and commissioning and the prior art is as follows: (1) The total investment of the system of the present invention is 12 million yuan, and the investment cost is reduced by 80% compared with the prior art; (2) The floor area of the system of the present invention is 5000 m 2 , and the floor area is reduced by 55% compared with the prior art; (3) The operating energy consumption of the system of the present invention is 8.83 kwh / t, and the energy consumption is reduced by 64% compared with the prior art; (4) The number of operation and maintenance personnel is reduced to 25, and the labor cost is reduced by 50% compared with the prior art; (5) In terms of production indexes, the cyanidation leaching rate reaches 90.5%, which is 0.3% higher than the prior art index; the washing rate of cyanide residue reaches 92.3%, which is 4.2% higher than the prior art index; the water content of cyanide residue is 12.2%, which is 2.8% lower than the prior art index.

[0169] Although the present invention has been described in detail by referring to the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, those of ordinary skill in the art can make various equivalent modifications or substitutions to the embodiments of the present invention, and all such modifications or substitutions should be within the scope of the present invention / Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A negative pressure suction filtration type cyanide gold extraction system, comprising a sedimentation tank (3), a precipitation tank (4), a noble liquid tank (5), a carbon adsorption device (6) and a lean liquid tank (7), characterized in that: The system further comprises one or more leaching tanks (1) and boiling pulping devices (10) corresponding to the leaching tanks (1) one by one; the leaching tank (1) is provided with a drainage pipe (1-4) connected to the sedimentation tank (4) and an overflow pipe (1-3) connected to the settling tank (3); a negative pressure chamber (1-1) is provided below the leaching tank (1) through a filter plate (1-2); the system further comprises a negative pressure manufacturing device (2); the negative pressure manufacturing device (2) comprises a connection container (2- 1) and an L-shaped tube (2-4); the upper end of the connecting container (2-1) is connected to each negative pressure chamber (1-1) through a negative pressure tube (1-6), and the lower end is connected to the upper end of the L-shaped tube (2-4); the upper end of the L-shaped tube (2-4) is connected to a water supply pipe (2-2) and an exhaust pipe (2-3), and the lower end of the L-shaped tube (2-4) is connected to a water tank (2-5); the water tank (2-5) is connected to a water pump (2-6-1) driven by a variable frequency speed regulating motor 2-6); an air pressure connecting pipe (2-5-1) is installed at the upper end of the water tank (2-5); a liquid level meter (2-7) is also installed on the water tank (2-5) and is located above the air pressure connecting pipe (2-5-1) and is used to sense and measure the water level in the water tank (2-5); the negative pressure manufacturing device (2) also includes a controller for collecting water level data in the water tank (2-5) through the liquid level meter (2-7) and for controlling the variable frequency speed regulating motor; the system also includes a boiling pulping device ( 10); the boiling pulping device (10) comprises a water distribution tank (10-1), the bottom of which is connected to a plurality of pulping pipes (10-2), and one side of which is connected to a fluid inlet pipe (10-5), the end of which is used to connect to a lean liquid submersible pump (7-1), a clean water pump or an air compressor; a crane is provided above each leaching tank for loading and digging gold-containing ore and hanging the boiling pulping device (10) during the leaching process.

2. The negative pressure filtration type cyanide gold extraction system as claimed in claim 1, characterized in that The number of the leaching tanks (1) is determined by calculation according to Formula 1: Formula 1: Where G is the number of leaching tanks, pieces; K—redundancy coefficient, 1.1~1.2; 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—ore bulk density, t / m 3 .

3. The negative pressure filtration type cyanide gold extraction system as claimed in claim 1, characterized in that The diameter and height of the L-shaped tube (2-4) are calculated and determined according to Formula 2 and Formula 3: Formula 2: Where φ is the diameter of L-shaped tube, m; K0—redundancy coefficient, 1.1~1.2; μ—Liquid flow rate in the L-shaped tube, designed to be 0.1-0.2 m / s; V—The filtrate output of the leaching tank determined by the negative pressure filtration experiment, m 3 / s; Formula 3: H = K1hP (ρ0 / ρ); Wherein, the height difference between the lower edge of the exhaust pipe at the top of the H-L-shaped tube and the highest liquid level in the water tank is m; K1—Redundancy coefficient, 1.1~1.2; h—the height of a water column that can be supported by ten standard atmospheres, which is 103.4m; P—vacuum degree required for leaching tank design, MPa; ρ0—Clean water density, t / m 3 ; ρ—filtrate density, t / m 3 .

4. The negative pressure filtration type cyanide gold extraction system according to claim 1, characterized in that: The upper part of the sedimentation tank (3) is a cylindrical cylinder (3-1) with an overflow trough (3-4) and a feed cylinder (3-3), and the lower part is a conical cylinder (3-2). The bottom end of the conical cylinder (3-2) is connected to an underflow slurry pump (3-6) through a discharge pipe, and the underflow slurry pump (3-6) is connected to each leaching tank (1) through a pipeline; the overflow trough (3-4) is connected to the sedimentation tank (4) through a clear liquid overflow pipe (3-5); and the feed cylinder (3-3) is connected to the discharge end of the overflow pipe (1-3).

5. The negative pressure filtration type cyanide gold extraction system as claimed in claim 4, characterized in that The diameter of the cylindrical barrel (3-1) is calculated and determined according to Formula 4: Formula 4: Where φ is the diameter of the cylindrical tube of the sedimentation tank, m; K2—safety factor, take 1.1~1.2; V1—The turbid liquid output determined by boiling pulping leaching test, m 3 / h; ρ1—density of turbid liquid, t / m 3 ; Where ρ1=100 / (C1 / ρ2+100-C1) C1—mass concentration of turbid liquid fed into the sedimentation tank, %; C2—mass concentration of bottom flow slurry discharged from the sedimentation tank, %; ρ2—suspended matter density, t / m 3 ; S—the mass of suspended solids treated per unit area of ​​the sedimentation tank per unit time, t / (m 2 .h); Where 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.

6. The negative pressure filtration type cyanide gold extraction system according to claim 1, characterized in that: The lean liquid pool (7) is located at one side of the precious liquid pool (5); the lean liquid pool (7) is provided with a sodium cyanide or environmentally friendly gold extraction agent solution addition pipe (8) and a lime solution addition pipe (9); the lean liquid pool (7) is provided with a lean liquid submersible pump (7-1) for conveying the lean liquid in the lean liquid pool (7) to the fluid inlet pipe (10-5); the precious liquid pool (5) is located at the end of the sedimentation tank (4); the carbon adsorption device (6) is arranged above the precious liquid pool (5); the water pump (2-6) is connected to the sedimentation tank (4) through a water pump drainage pipe (2-6-3).

7. A control method for a negative pressure filtration type cyanidation gold extraction system according to any one of claims 1 to 6, characterized in that: Step 1: using an electric grab bucket to load gold-containing ore raw materials into the leaching tank (1) and trim and flatten them; Step 2: injecting lean solution into the leaching tank (1), requiring the lean solution to cover the gold-containing ore raw material layer; Step 3: start the negative pressure manufacturing device (2), and use an electric crane to hang the boiling pulping device (10) from the front end to the rear end of the leaching tank (1) to perform boiling pulping in sections; during the process, the boiling pulping device (10) is first filled with high-pressure air through the fluid inlet pipe (10-5), the electric crane hook is dropped, and the pulping pipe (10-2) is inserted into the gold ore raw material layer. After the air is continuously filled in the process, the lean liquid is filled in through the fluid inlet pipe (10-5); Step 4: After the boiling pulping operation in the leaching tank (1) is completed, the liquid is allowed to stand until the supernatant is completely clarified, and the valve of the discharge pipe (1-5) is opened, and the supernatant is discharged into the sedimentation tank (4) by gravity; Step 5: After the above operations are completed, the cyanide residue in the leaching tank is further discharged through negative pressure filtration; when the overall moisture content reaches below 15%, the cyanide residue is taken out using an electric grab.

8. The control method according to claim 7, characterized in that The specific control method of the negative pressure manufacturing device (2) is as follows: Step (1): close the water tank drain pipe valve (2-5-4) and the water pump inlet pipe valve (2-6-2), and open the exhaust pipe valve (2-3-1), the air pressure connecting pipe valve (2-5-2) and the water supply pipe valve (2-2-1) in sequence, and add lean liquid into the L-shaped pipe (2-4) and the water tank (2-5) through the water supply pipe (2-2); Step (ii): when the air pressure connecting pipe (2-5-1) begins to overflow, the air pressure connecting pipe valve (2-5-2) is closed; when the exhaust pipe (2-3) begins to overflow, the water supply pipe valve (2-2-1) and the exhaust pipe valve (2-3-1) are closed in sequence; Step (iii): after the water replenishment is completed, the water pump (2-6) is started in sequence, the water pump water inlet pipe valve (2-6-2) and the air pressure connecting pipe valve (2-5-2) are opened, and part of the liquid in the leaching tank (1) is extracted through the filter plate (1-2), and then sequentially discharged to the sedimentation tank (4) through the negative pressure pipe (1-6), the L-shaped pipe (2-4), and the water tank (2-5) by the water pump (2-6); During the negative pressure filtration operation, the liquid level meter (2-7) detects data and the controller timely adjusts the operating frequency to control the drainage volume of the water pump (2-6) to ensure that the liquid level in the water tank (2-5) is within the set range, thereby obtaining a continuous and stable vacuum negative pressure effect.

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