Device and method for separating and recovering gold and silver from gold slag using water regia

Abstract

The present invention relates to an apparatus and method for separating and recovering gold and silver from regia water slag, comprising: a recovery crucible formed by connecting an upper crucible body, a middle crucible body, and a lower crucible body arranged sequentially from top to bottom; a smooth dome-shaped condensation cover formed on the top of the upper crucible body; a funnel-shaped reflux receiving member fixedly mounted on the upper end of the middle crucible body, the member having conductive holes extending therethrough; an adjustable fixing mechanism to sequentially abut, tighten, and seal the upper, middle, and lower crucible bodies together to form a recovery crucible; a vacuum unit; a heating mechanism comprising an upper heating element and a lower heating element spaced apart and fixed to the inner wall of an insulated furnace box; and a chlorine absorption mechanism installed within an air duct for graded absorption of chlorine gas discharged from the recovery crucible. The present invention achieves the separation and recovery of gold and silver from regia water and slag, effectively improving the efficiency of gold and silver separation and recovery, achieving thorough gold and silver separation, a high direct metal recovery rate, and a short process.

Description

Technical Field

[0001] The present invention relates to the technical field of non-ferrous metal vacuum metallurgy, specifically to a device and method for separating and recovering gold and silver from aqueous regia metallurgy slag, and relates to precious metal pyrometallurgy, and in particular to a device and method for separating and recovering gold and silver from aqueous regia metallurgy slag by a "low temperature-high temperature" two-stage vacuum distillation and gasification process. Background Art

[0002] Due to its high conductivity and excellent corrosion resistance, gold is widely used in the electronics, aerospace, and medical industries. The main sources of gold are vein gold deposits, placer gold deposits, and associated minerals with heavy metals such as copper and lead. Crude gold primarily contains silver, copper, lead, iron, nickel, and platinum group metals. Aqua regia leaching is a common crude gold refining process. When the impurity silver content in the crude gold exceeds 5%, the silver reacts with chloride ions during the aqua regia leaching process to form a silver chloride precipitate that coats the surface of the gold particles, preventing further dissolution. This ultimately results in an aqua regia gold slag containing 0.5-10% gold.

[0003] Currently, the treatment of regia gold slag is primarily based on the idea of dissolving or converting silver chloride and selectively recovering gold. Common methods include ammonia leaching-hydrazine hydrate reduction, thiosulfate leaching-reduction, thiourea reduction-zinc powder replacement, and direct zinc powder reduction. For example, Chinese patent CN117431407A discloses a method for producing silver chloride from gold-exchanged pyrometallurgical silver slag and recovering the silver using hydrazine hydrate reduction, yielding silver powder with a silver content of 99.5%. Chinese patent CN116372157A employs a similar method to recover silver from silver chloride, ultimately obtaining silver powder with a purity greater than 99.99% by thoroughly washing the silver chloride with various cleaning agents.

[0004] The existing process generally has the problem of incomplete separation due to the mutual coating of silver and gold, resulting in a long process, low direct recovery rate of precious metals, high requirements for raw material composition, and the full wet process inevitably leads to large amounts of toxic wastewater and high consumption of chemical reagents.

[0005] Therefore, the research purpose of the present invention is to design a device and method for separating and recovering gold and silver from aqua regia gold slag with strong applicability to raw materials, thorough gold and silver separation, high metal direct recovery rate and short process. Summary of the Invention

[0006] In response to the technical problems existing in the above-mentioned prior art, the present invention provides a device and method for separating and recovering gold and silver from gold slag using aqua regia. The device and method for separating and recovering gold and silver from gold slag using aqua regia can effectively solve the technical problems existing in the above-mentioned prior art.

[0007] The technical solution of the present invention is:

[0008] A device for separating and recovering gold and silver from aqueous regia gold slag, comprising:

[0009] The insulation furnace box has a corresponding closing door on the front side that can be opened and closed;

[0010] The recovery crucible is detachably installed in the heat-insulating furnace box, and is composed of an upper crucible body, a middle crucible body and a lower crucible body which are sequentially distributed from top to bottom; a smooth dome-shaped condensation cover is formed on the top of the upper crucible body, and a bucket-shaped reflux receiving member is fixedly installed on the upper end of the middle crucible body, and a plurality of partition plates are vertically fixedly installed on the upper end of the reflux receiving member in an annular array, and a corresponding guide plate is vertically fixedly connected to the lower end of the partition plate symmetrically on the left and right, and the distance between the end portions of the two guide plates installed on two adjacent partition plates and arranged oppositely gradually decreases, and the reflux receiving member located between the two guide plates installed on the same partition plate is provided with a conducting hole running through it from top to bottom, and a corresponding receiving groove is formed downwardly in the middle portion of the reflux receiving member;

[0011] An adjusting and fixing mechanism is used to movably mount the lower crucible body up and down, and to fix the upper crucible body and the middle crucible body after the lower crucible body is moved upward into position, and the recovery crucible is formed by abutting, tightening and sealing the upper crucible body, the middle crucible body and the lower crucible body in sequence;

[0012] A vacuum unit, wherein a corresponding air guide pipe is fixedly installed on the top of the insulation furnace box, one end of the air guide pipe extends into the insulation furnace box and its end abuts and communicates with the middle of the dome of the upper crucible body, and the other end is connected to the outside and to the vacuum unit respectively through a corresponding tee pipe and a valve;

[0013] The heating mechanism comprises an upper heating element and a lower heating element, which are spaced apart from each other and fixed to the inner side wall of the heat-insulating furnace box. The upper and lower portions of the reflux receiving element cooperate to form a high-temperature distillation zone. The lower crucible body cooperates with the reflux receiving element to form a low-temperature distillation zone. The upper heating element is used to perform high-temperature heating and distillation on the substance in the high-temperature distillation zone, and the lower heating element is used to perform low-temperature heating and distillation on the substance in the low-temperature distillation zone.

[0014] A chlorine absorption mechanism is installed in the air guide pipe for absorbing the chlorine discharged from the recovery crucible in stages, or is installed at the end of the air guide pipe to collect the chlorine discharged from the recovery crucible.

[0015] The adjusting and fixing mechanism includes a sleeve member fixedly connected to the bottom of the lower crucible body and a stud fixedly installed on the inner bottom of the insulation furnace box, and the inner wall of the sleeve member is evenly distributed with internal threads adapted to the studs; the lower crucible body is fixedly installed in the insulation furnace box by screwing the sleeve member to the studs, and the upper crucible body, the middle crucible body and the lower crucible body are tightened and fixed and sealed by rotating the sleeve member upward to form the recovery crucible.

[0016] Auxiliary tightening mechanisms for enhancing the installation stability of the recovery crucible are provided above and below the recovery crucible. The auxiliary tightening mechanisms include a plurality of support columns spaced apart and fixed to the top or bottom of the insulation furnace box. The support columns are distributed circumferentially with the recovery crucible as the axis. The ends of the support columns that are not connected to the insulation furnace box are fixedly connected to corresponding support rings through corresponding elastic members. After the recovery crucible is installed in place, the elastic member has a movement tendency to push the support ring to press against the top or bottom of the recovery crucible.

[0017] The air guide pipe is a water-cooled sleeve, and its air inlet section and air outlet section are respectively provided with corresponding chlorine absorption zone 1 and chlorine absorption zone 2. The chlorine absorption mechanism includes activated carbon loaded with CuCl2 filled in the chlorine absorption zone 1 and a mixture of Ca(OH)2 and Fe2O3 filled in the chlorine absorption zone 2.

[0018] The upper heating element and the lower heating element are both heating elements that are spirally distributed upward, and the heating element is made of high-purity graphite. The lower heating element is spirally installed on the outside of the lower crucible body, and the upper heating element is spirally installed on the outside of the middle crucible body where the reflux receiving element is located.

[0019] A stepped exhaust hole is provided in the middle of the dome of the upper crucible body. When the recovery crucible is installed in place, the bottom of the air guide tube cooperates with the corresponding gasket to abut and be fixed on the stepped portion of the guide hole of the upper crucible body and is connected to the recovery crucible.

[0020] The inner side wall of the upper crucible body is located at the connection with the lower crucible body to form a downwardly inclined arc surface, and is streamlinedly connected to the inner side wall of the reflux receiving member.

[0021] All side walls and closed doors of the insulation furnace box are sandwich structures and filled with corresponding insulation materials. The insulation material is made of graphite hard felt. The diameters of the middle crucible body and the lower crucible body are the same, and the middle crucible body and the reflux receiving member are made of high-purity quartz, and the lower crucible body is made of high-purity graphite. The vacuum unit is composed of a mechanical pump and a molecular pump, and its vacuum degree is 10 -2 ~10-6 Pa high vacuum, also includes a vacuum measuring device, the vacuum measuring device is a high-precision vacuum gauge, the recovery crucible is also provided with a temperature measuring thermocouple for respectively detecting the middle crucible body and the lower crucible body.

[0022] A method for separating and recovering gold and silver from aqueous regia gold slag, using the above-mentioned apparatus for separating and recovering gold and silver from aqueous regia gold slag, comprises the following steps:

[0023] S1, the lower crucible is fixedly installed in the insulation furnace box, and the aqueous regia metallurgical slag is placed in the lower crucible, and the middle crucible and the upper crucible are sequentially stacked and installed on the lower crucible, and the air guide tube is installed above the upper crucible in abutment and communication manner; the lower crucible is then moved upward and fixed by the adjusting and fixing mechanism, so that the upper crucible, the middle crucible, and the lower crucible are sequentially abutted, tightened, and sealed;

[0024] S2, controlling a certain system pressure and a temperature of the low-temperature distillation zone by a vacuum unit and a heating mechanism, respectively, so that the silver chloride is vaporized and volatilized upward by low-temperature distillation, while the gold remains at the inner bottom of the lower crucible body;

[0025] S3, the vaporized silver chloride produced in step S2 evaporates upward and enters the upper crucible through the conducting hole of the reflux receiving member, the silver chloride liquefies on the smooth dome-shaped condensation cover and sequentially refluxes along the condensation cover to the surrounding edges and the inner sidewall of the upper crucible, and is guided along the reflux receiving member to gather in the receiving groove and the reflux receiving member;

[0026] S4, after the reflux is completed, the temperature of the high-temperature distillation zone is controlled by the heating mechanism, and the silver chloride is decomposed into silver and chlorine in the high-temperature distillation zone through high-temperature distillation. The chlorine evaporates upward and is absorbed or collected by the chlorine absorption mechanism, and the silver remains in the reflux receiving member and the receiving tank.

[0027] The system pressure of the distillation process in step S2 is 10 -3 ~10 -5 Pa; the heating temperature of the low-temperature distillation zone is 750~1000℃, the time of the low-temperature distillation is 30~120min, and during the low-temperature distillation, the heating temperature of the high-temperature distillation zone is 600~750℃; the heating temperature of the high-temperature distillation zone in step S3 is 1100~1300℃, and the time of the high-temperature distillation is 30~120min.

[0028] Advantages of the present invention:

[0029] 1) In the present invention, gold is separated by lower-layer low-temperature distillation during the separation of aqua regia from gold slag. The vaporized silver chloride flows upward through the conduction hole of the reflux receiving member, condenses into liquid on the dome-shaped condensation cover, and then flows along the dome to the surrounding areas, and then flows downward along the inner side wall of the recovery crucible to the reflux receiving member. The bucket-shaped reflux receiving member is vertically fixed with a plurality of partition plates arranged in a ring array. The lower ends of the partition plates are fixed with relatively arranged guide plates. The distal ends of the guide plates extend to a receiving groove provided in the middle of the reflux receiving member. The guide plates are arranged around the conduction hole to guide and protect the liquid silver chloride, effectively preventing it from flowing back from the conduction hole to the bottom of the recovery crucible, thereby ensuring the effect of separating gold and silver from the gold slag. The non-standard reflux receiving member of the present invention cooperates with the heating mechanisms spaced above and below and set at different temperatures for the gold and silver recovery treatment of gold slag, and can realize the recovery of gold and silver in the same equipment. It can not only ensure that the separated gaseous silver chloride is smoothly transmitted upward, but also guide and collect the condensed liquid silver chloride, and then decompose silver and chlorine through high-temperature distillation. The chlorine is completely absorbed or collected by the chlorine absorption mechanism, thereby realizing the separation and recovery of water regia and gold and silver in the slag, and effectively improving the efficiency of separation and recovery.

[0030] 2) The present invention adds a non-standard reflux receiving part for synchronously separating and recovering silver from gold slag. In order to facilitate the loading and placing of materials, the present invention further divides the recovery crucible into an upper crucible body, a middle crucible body and a lower crucible body, which are sequentially distributed in the upper, middle and lower parts, and adds a corresponding adjustment and fixing mechanism for stable installation and convenient disassembly of the recovery crucible. By fixing a corresponding sleeve part under the lower crucible body and fixing a corresponding stud on the bottom inner side of the insulation furnace box, the lower crucible body is fixedly installed in the insulation furnace box by screwing the sleeve part to the stud, and the material is filled on the lower crucible body; then, the middle crucible body and the upper crucible body are sequentially superimposed and installed on the lower crucible body, and the sleeve part is rotated upward to move the upper crucible body, the middle crucible body and the lower crucible body upward, so that the air guide tube abuts and connects with the step portion of the upper crucible body until the upper crucible body, the middle crucible body and the lower crucible body are tightly fixed to each other and sealed. The present invention utilizes an adjustable fixing mechanism to not only fix and seal the recovery crucible, but also quickly and conveniently disassemble the recovery crucible to facilitate the taking and placing of materials, so that the reflux receiving member can be put into practical use and synchronous silver recovery can be achieved, thereby ensuring the practical effect of the present invention.

[0031] 3) The present invention uses the air guide tubes and the adjusting and fixing mechanisms arranged at the upper and lower parts of the middle part of the recovery crucible to cooperate with each other to tighten and fix the recovery crucible. In order to further improve the support stability and reduce the operation convenience of personnel when installing the recovery crucible, the present invention respectively provides corresponding auxiliary tightening mechanisms at the upper and lower ends of the recovery crucible. When the lower crucible body is screwed to the bottom with the stud through the sleeve part, the elastic part of the auxiliary tightening mechanism on the lower side is compressed; after the recovery crucible is installed, the support ring parts at the upper and lower ends are sleeved on the upper and lower ends of the recovery crucible, and both push the auxiliary support recovery crucible under the elastic force of the elastic parts connected to them, thereby enhancing the stability of the recovery crucible installation. In addition, during installation, the auxiliary tightening mechanism on the lower side supports and limits, which can reduce the support force of personnel on the lower crucible body during installation, further ensuring the practical effect of the present invention.

[0032] 4) The chlorine absorption mechanism of the present invention is installed on a water-cooled jacket and includes activated carbon loaded with CuCl2 and filled in the first chlorine absorption zone and a mixture of Ca(OH)2 and Fe2O3 filled in the second chlorine absorption zone. The activated carbon loaded with CuCl2 and the mixture of Ca(OH)2 and Fe2O3 ensure comprehensive and timely absorption of the separated chlorine.

[0033] 5) The present invention uses an optimized and improved device for separating gold and silver from gold slag using regia water to recover gold and silver simultaneously. -3 ~10 -5 Pa, and heated to 750 ~ 1000 ℃ for low-temperature distillation for 30 ~ 120 minutes, so that the gold is separated and remains in the lower crucible body, and the silver is uploaded as gaseous silver chloride and passes through the conductive hole of the reflux receiving piece and condensed on the dome of the upper crucible body to become liquid, and then flows along the inner wall of the upper crucible body to the reflux receiving piece. During the low-temperature distillation, the heating temperature of the high-temperature distillation zone is 600 ~ 750 ℃, which effectively prevents the gaseous silver chloride from condensing and refluxing at the reflux receiving piece to ensure the separation effect, and the liquid silver chloride evaporates at this temperature The high-temperature distillation zone is preheated to speed up the efficiency of subsequent high-temperature distillation on the basis of ensuring the smooth reflux of liquid silver chloride; the high-temperature distillation zone is then heated to 1100-1300°C for high-temperature distillation for 30-120 minutes to separate the silver, and the chlorine is volatilized and then fully and promptly absorbed by activated carbon loaded with CuCl2 and a mixture of Ca(OH)2 and Fe2O3, thereby ensuring that the method for separating gold and silver from aqua regia gold slag has the advantages of short process, low cost, high efficiency, environmental friendliness, and high precious metal yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the present invention.

[0035] Figure 2for Figure 1 Schematic cross-section diagram.

[0036] Figure 3 It is a structural diagram of the reflux receiving component.

[0037] Figure 4 Schematic diagram of the circulation of gaseous silver chloride and liquid silver chloride in Example 2.

[0038] In the accompanying drawings: insulation furnace box 1, recovery crucible 2, upper crucible body 201, middle crucible body 202, lower crucible body 203, chlorine absorption mechanism 3, reflux receiving member 4, partition plate 5, guide plate 6, guide hole 7, receiving groove 8, adjustment and fixing mechanism 9, sleeve member 901, stud 902, vacuum unit 10, air guide pipe 11, chlorine absorption zone 1101, chlorine absorption zone 2 1102, heating mechanism 12, upper heating element 1201, lower heating element 1202, auxiliary tightening mechanism 13, support column 1301, elastic member 1302, support ring 1303. DETAILED DESCRIPTION

[0039] In order to facilitate understanding by those skilled in the art, the structure of the present invention is further described in detail with reference to the embodiments and the accompanying drawings:

[0040] Example 1

[0041] refer to Figure 1-3 , a device for separating and recovering gold and silver from water regia gold slag, comprising:

[0042] The heat preservation furnace box 1 has a corresponding closing door on its front side that can be opened and closed;

[0043] The recovery crucible 2 is detachably mounted in the heat-insulating furnace box 1 and is connected by an upper crucible body 201, a middle crucible body 202 and a lower crucible body 203 which are sequentially distributed from top to bottom; a smooth dome-shaped condensation cover is formed on the top of the upper crucible body 201, and a bucket-shaped reflux receiving member 4 is fixedly mounted on the upper end of the middle crucible body 202. A plurality of partition plates 5 are vertically fixedly mounted on the upper end of the reflux receiving member 4 in a circular array, and a corresponding guide plate 6 is vertically fixedly fixed to the lower end of the partition plate 5 in a symmetrical manner. The distance between the end portions of the two guide plates 6 installed on two adjacent partition plates 5 and arranged oppositely is gradually reduced. A conducting hole 7 is provided on the reflux receiving member 4 between the two guide plates 6 installed on the same partition plate 5, and a corresponding receiving groove 8 is formed downwardly in the middle of the reflux receiving member 4, wherein the two guide plates 6 connected to one partition plate 5 can also be integrally formed to form a ring structure;

[0044] The adjusting and fixing mechanism 9 is used to movably mount the lower crucible body 203 up and down, and the lower crucible body 203 is used to fix the upper crucible body 201 and the middle crucible body 202 after being moved upward into position, and the upper crucible body 201, the middle crucible body 202 and the lower crucible body 203 are sequentially abutted, tightened and sealed to form the recovery crucible 2;

[0045] The vacuum unit 10 is provided with a corresponding air guide pipe 11 fixedly mounted on the top of the insulation furnace box 1. One end of the air guide pipe 11 extends into the insulation furnace box 1 and abuts against the middle of the dome of the upper crucible body 201. The other end of the air guide pipe 11 is connected to the outside and to the vacuum unit 10 through corresponding tees and valves.

[0046] The heating mechanism 12 comprises an upper heating element 1201 and a lower heating element 1202, which are spaced apart from each other and fixed to the inner sidewall of the heat-insulating furnace box 1. The upper and lower portions of the reflux receiving member 4 cooperate to form a high-temperature distillation zone. The lower crucible body 203 cooperates with the reflux receiving member 4 to form a low-temperature distillation zone. The upper heating element 1201 is used to perform high-temperature heating and distillation on the substance in the high-temperature distillation zone, and the lower heating element 1202 is used to perform low-temperature heating and distillation on the substance in the low-temperature distillation zone.

[0047] The chlorine gas absorption mechanism 3 is installed in the air guide pipe 11 for absorbing the chlorine gas discharged from the recovery crucible 2 in stages or is installed at the end of the air guide pipe 11 to collect the chlorine gas discharged from the recovery crucible 2 .

[0048] In the process of separating gold slag from aqua regia, the present invention separates gold through low-temperature distillation in the lower layer, and the vaporized silver chloride flows upward through the conduction hole 7 of the reflux receiving member 4, and after condensing into liquid on the dome-shaped condensation cover, it is guided to the surroundings along the dome, and is guided downward along the inner wall of the recovery crucible 2 to the reflux receiving member 4. The bucket-shaped reflux receiving member 4 is vertically fixed with a plurality of partition plates 5 arranged in a ring array, and the lower end of the partition plate 5 is fixed with a relatively arranged guide plate 6, and the end portion of the guide plate 6 extends to the receiving groove 8 provided in the middle of the reflux receiving member 4. The guide plate 6 is arranged around the conduction hole 7 to guide and protect the liquid silver chloride, effectively preventing it from flowing back from the conduction hole 7 to the bottom of the recovery crucible 2, thereby ensuring the effect of separating gold and silver from the gold slag. The non-standard reflux receiving member 4 of the present invention cooperates with the heating mechanism 12 spaced apart and set at different temperatures for the gold and silver recovery treatment of gold slag, and can realize the recovery of gold and silver in the same equipment. It can not only ensure that the separated gaseous silver chloride is smoothly transmitted upward, but also guide and collect the condensed liquid silver chloride, and then decompose silver and chlorine through high-temperature distillation. The chlorine is completely absorbed or collected by the chlorine absorption mechanism 3, thereby realizing the separation and recovery of water regia and gold and silver in the slag, and effectively improving the efficiency of separation and recovery.

[0049] The adjusting and fixing mechanism 9 includes a sleeve member 901 fixedly connected to the bottom of the lower crucible body 203 and a stud 902 fixedly installed on the inner bottom of the insulation furnace box 1. The inner wall of the sleeve member 901 is evenly distributed with internal threads that are compatible with the stud 902; the lower crucible body 203 is fixedly installed in the insulation furnace box 1 by screwing the sleeve member 901 to the stud 902, and the upper crucible body 201, the middle crucible body 202 and the lower crucible body 203 are tightened and fixed by rotating the sleeve member 901 upward and sealed to form the recovery crucible 2.

[0050] The present invention adds a non-standard reflux receiving part 4 for synchronous separation and recovery of silver in gold slag. In order to facilitate the loading and unloading of materials, the present invention further divides the recovery crucible 2 into an upper crucible body 201, a middle crucible body 202 and a lower crucible body 203 which are sequentially arranged in the upper, middle and lower parts, and adds a corresponding adjustment and fixing mechanism 9 for stable installation and convenient disassembly of the recovery crucible 2. By fixing a corresponding sleeve member 901 under the lower crucible body 203 and fixing a corresponding stud 902 on the inner bottom of the heat preservation furnace box, the sleeve member 901 is screwed to the screw. The column 902 securely mounts the lower crucible 203 within the heat-insulating furnace box, and the lower crucible 203 is filled with material. The middle crucible 202 and the upper crucible 201 are then sequentially stacked and mounted on the lower crucible 203. The sleeve 901 is rotated upward to move the upper, middle, and lower crucibles 201, 202, and 203 upward, allowing the air guide 11 to abut and connect with the stepped portion of the upper crucible 201, until the upper, middle, and lower crucibles 201, 202, and 203 are tightly secured to each other and sealed. The present invention utilizes the adjustable fixing mechanism 9 to not only securely and sealably mount the recovery crucible 2, but also quickly and conveniently disassemble the recovery crucible 2 to facilitate the removal of material, thereby enabling the practical application of the reflux receiving member 4 and achieving simultaneous silver recovery, thereby ensuring the practical effects of the present invention.

[0051] Auxiliary tightening mechanisms 13 for enhancing the installation stability of the recovery crucible 2 are provided above and below the recovery crucible 2. The auxiliary tightening mechanism 13 includes a plurality of support columns 1301 spaced apart and fixed to the top or bottom of the insulation furnace box 1. The support columns 1301 are distributed circumferentially with the recovery crucible 2 as the axis. The end of the support column 1301 not connected to the insulation furnace box 1 is fixedly connected to a corresponding support ring 1303 through a corresponding elastic member 1302. After the recovery crucible 2 is installed in place, the elastic member 1302 has a movement tendency to push the support ring 1303 to press tightly against the top or bottom of the recovery crucible 2.

[0052] The present invention is to fix the recovery crucible 2 by cooperating with the air guide tube 11 and the adjustment fixing mechanism 9 arranged at the upper and lower middle parts of the recovery crucible 2 to tighten each other for fixing the recovery crucible 2. In order to further improve the support stability and reduce the operation convenience of personnel when installing the recovery crucible 2, the present invention is respectively provided with corresponding auxiliary tightening mechanisms 13 at the upper and lower ends of the recovery crucible 2. When the lower crucible body 203 is screwed to the bottom with the stud 902 through the sleeve member 901, the elastic member 1302 of the auxiliary tightening mechanism 13 on the lower side is compressed; after the recovery crucible 2 is installed, the support ring members 1303 at the upper and lower ends are sleeved on the upper and lower ends of the recovery crucible 2, and both push the auxiliary support recovery crucible 2 under the elastic force of the elastic members 1302 connected thereto, thereby enhancing the stability of the installation of the recovery crucible 2, and the auxiliary tightening mechanism 13 on the lower side is supported and limited during installation, which can reduce the support force of personnel on the lower crucible body 203 during installation, further ensuring the practical effect of the present invention.

[0053] The air guide pipe 11 is a water-cooled sleeve, and its air inlet section and air outlet section are respectively provided with corresponding chlorine absorption zone 1101 and chlorine absorption zone 2 1102. The chlorine absorption mechanism 3 includes activated carbon loaded with CuCl2 filled in the chlorine absorption zone 1101 and a mixture of Ca(OH)2 and Fe2O3 filled in the chlorine absorption zone 2 1102.

[0054] The upper heating element 1201 and the lower heating element 1202 are both heating elements that are spirally distributed upward, and the heating element is made of high-purity graphite. The lower heating element 1202 is spirally installed on the outside of the lower crucible body 203, and the upper heating element 1201 is spirally installed on the outside of the middle crucible body 202 where the reflux receiving element 4 is located.

[0055] A stepped exhaust hole is provided in the middle of the dome of the upper crucible body 201. When the recovery crucible 2 is installed in place, the bottom of the air guide tube 11 cooperates with the corresponding gasket to abut and be fixed to the stepped portion of the guide hole 7 of the upper crucible body 201, and is connected to the recovery crucible 2.

[0056] The inner sidewall of the upper crucible body 201 is located at the connection with the lower crucible body 203 and forms a downwardly inclined arc surface, and forms a streamlined connection with the inner sidewall of the reflux receiving member 4 .

[0057] All side walls and closed doors of the heat preservation furnace box 1 are sandwich structures and filled with corresponding heat preservation materials. The material of the heat preservation material is graphite hard felt. The diameters of the middle crucible body 202 and the lower crucible body 203 are the same. The middle crucible body 202 and the reflux receiving member 4 are made of high-purity quartz, and the material of the lower crucible body 203 is high-purity graphite. The vacuum unit 10 is composed of a mechanical pump and a molecular pump, and its vacuum degree is 10-2 ~10 -6 Pa high vacuum, also includes a vacuum measuring device, the vacuum measuring device is a high-precision vacuum gauge, the recovery crucible 2 is also provided with a temperature measuring thermocouple for respectively detecting the middle crucible body 202 and the lower crucible body 203, the top of the insulation furnace box 1 is also provided with a corresponding pressure relief valve and a pressure gauge, after the distillation is completed, the pressure can be released through the pressure relief valve to facilitate the removal of gold and silver.

[0058] Example 2

[0059] refer to Figure 4 A method for separating and recovering gold and silver from aqueous regia gold slag using the above-mentioned aqueous regia gold slag separation and recovery device comprises the following steps:

[0060] S1, the lower crucible body 203 is fixedly installed in the insulation furnace box 1, and the aqueous regia metallurgical slag is placed in the lower crucible body 203, and the middle crucible body 202 and the upper crucible body 201 are sequentially stacked and installed on the lower crucible body 203, and the air guide tube 11 is installed above the upper crucible body 201 in abutment and communication; then, the lower crucible body 203 is moved upward and fixed by the adjusting and fixing mechanism 9, so that the upper crucible body 201, the middle crucible body 202, and the lower crucible body 203 are sequentially abutted, tightened, and sealed;

[0061] S2, controlling the system pressure and the temperature of the low-temperature distillation zone by the vacuum unit 10 and the heating mechanism 12, respectively, so that the silver chloride vaporizes and evaporates upward through low-temperature distillation, while the gold remains on the inner bottom of the lower crucible body 203;

[0062] S3, the vaporized silver chloride produced in step S2 evaporates upward and enters the upper crucible body 201 through the conducting hole 7 of the reflux receiving member 4, the silver chloride liquefies on the smooth dome-shaped condensation cover and sequentially refluxes along the condensation cover to the surrounding edges and the inner wall of the upper crucible body 201, and is guided along the reflux receiving member 4 to gather in the receiving groove 8 and the reflux receiving member 4;

[0063] S4, the temperature of the high-temperature distillation zone is controlled by the heating mechanism 12, and the silver chloride is decomposed into silver and chlorine in the high-temperature distillation zone through high-temperature distillation. The chlorine evaporates upward and is absorbed or collected by the chlorine absorption mechanism 3, and the silver remains in the reflux receiving member 4 and the receiving tank 8.

[0064] The system pressure of the distillation process in step S2 is 10 -3 ~10 -5Pa; the heating temperature of the low-temperature distillation zone is 750~1000℃, the time of the low-temperature distillation is 30~120min, and during the low-temperature distillation, the heating temperature of the high-temperature distillation zone is 550~800℃; the heating temperature of the high-temperature distillation zone in step S3 is 1100~1300℃, and the time of the high-temperature distillation is 30~120min.

[0065] The invention uses an optimized and improved device for separating gold and silver from gold slag by using water regia to recover gold and silver simultaneously. -3 ~10 -5 Pa, and heated to 750-1000°C for low-temperature distillation for 30-120 minutes, so that the gold is separated and remains in the lower crucible body 203, and the silver is uploaded as gaseous silver chloride and passes through the conducting hole 7 of the reflux receiving member 4 and condensed into liquid on the dome of the upper crucible body 201, and then guided along the inner wall of the upper crucible body 201 to the reflux receiving member 4. During the low-temperature distillation, the heating temperature of the high-temperature distillation zone is 600-750°C, which effectively prevents the gaseous silver chloride from condensing and refluxing at the reflux receiving member, thereby ensuring the separation effect, and the liquid silver chloride is At this temperature, the volatility is low, and on the basis of ensuring the smooth reflux of liquid silver chloride, the high-temperature distillation zone is preheated to accelerate the efficiency of subsequent high-temperature distillation; the high-temperature distillation zone is then heated to 1100-1300°C for high-temperature distillation for 30-120 minutes to separate the silver. After the chlorine volatilizes, it is fully and timely absorbed by activated carbon loaded with CuCl2 and a mixture of Ca(OH)2 and Fe2O3, thereby ensuring that the method for separating gold and silver from aqua regia gold slag has a short process, low cost, high efficiency, environmental friendliness, and a high yield of precious metals.

[0066] Example 3

[0067] The difference from Example 2 is that: a slag containing 0.5% gold by mass and 73.3% silver by mass is placed in the lower crucible 203, and the system pressure is 10 -4 Vacuum distillation separation was performed under the conditions of Pa, distillation temperature of the low-temperature zone was 900°C, distillation time was 45 minutes, during the low-temperature distillation, the heating temperature of the high-temperature distillation zone was 650°C, the distillation temperature of the high-temperature zone was 1150°C, and the distillation time was 45 minutes; after treatment, gold was enriched in the bottom lower crucible body 203, with a purity of 99.7% and a direct yield higher than 99.9%; silver was produced by the decomposition of silver chloride and enriched in the reflux receiving member 4 of the middle crucible body 202 in the high-temperature distillation zone, with a purity of 99.3% and a direct yield of 97.2%. A small amount of silver chloride vapor diffused into the chlorine absorption device before decomposition, resulting in a decrease in the direct yield of silver. This part of silver can be recovered after the absorption device fails.

[0068] Example 4

[0069] The difference from Example 2 is that: a slag containing 8% gold by mass and 68.2% silver by mass is placed in the lower crucible 203 in the low temperature zone, and the slag is heated to 10°C. -4 Vacuum distillation separation was carried out under the conditions of Pa, distillation temperature of the low-temperature zone was 950°C, distillation time was 45 minutes, during the low-temperature distillation, the heating temperature of the high-temperature distillation zone was 750°C, the distillation temperature of the high-temperature zone was 1200°C, and the distillation time was 45 minutes; after treatment, gold was enriched in the lower crucible body 203 at the bottom, with a purity of 99.6% and a direct yield higher than 99.5%; silver was produced by the decomposition of silver chloride and enriched in the reflux receiving part 4 of the middle crucible body 202 in the high-temperature distillation zone, with a purity of 99.1% and a direct yield of 96.4%.

[0070] Comparative Example 1:

[0071] The same gold content of 0.5% and silver content of 70.3% in the regia gold slag was distilled and separated in a single temperature zone vacuum distillation furnace. The system pressure was 10 -4 Pa, distillation temperature 900 ° C, distillation time 90 minutes; after treatment, gold is enriched at the bottom of the high-purity graphite crucible with a purity of 98.4% and a direct yield higher than 99.9%; silver is enriched in the form of silver chloride in the upper condensation zone, and elemental silver cannot be directly obtained.

[0072] Comparative Example 2:

[0073] The same gold content of 0.5% and silver content of 70.3% in the regia gold slag was distilled and separated in a single temperature zone vacuum distillation furnace. The system pressure was 10 -4 Pa, distillation temperature 1200 ° C, distillation time 90 minutes; after treatment, gold is enriched at the bottom of the high-purity graphite crucible with a purity of 98.4% and a direct yield of 92.6%. A small amount of gold evaporates with silver chloride to the upper condensation zone, and the crude silver in the condensation zone contains 8.4% chlorine. The silver chloride is not completely decomposed, and the purpose of completely separating gold and silver and obtaining the metal element in one step cannot be achieved.

[0074] Thus, using the device and method of the present invention to process gold slag can yield crude gold and silver with a gold and silver content exceeding 99%, a direct gold recovery rate exceeding 99.5%, and a direct silver recovery rate exceeding 96.7%. The entire process generates no waste, three wastes, and features a short process, low cost, and high efficiency.

[0075] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A device for separating and recovering gold and silver from gold slag using aqua regia, characterized in that: include: A heat preservation furnace box (1) having a corresponding closing door on the front side thereof which can be opened and closed; The recovery crucible (2) is detachably mounted in the heat-insulating furnace box (1) and is formed by connecting an upper crucible body (201), a middle crucible body (202) and a lower crucible body (203) which are sequentially arranged from top to bottom; a smooth dome-shaped condensation cover is formed on the top of the upper crucible body (201); a bucket-shaped reflux receiving member (4) is fixedly mounted on the upper end of the middle crucible body (202); and a plurality of reflux receiving members (4) are vertically fixedly mounted on the upper end of the reflux receiving member (4) in a circular array. A plurality of partition plates (5), wherein the lower ends of the partition plates (5) are fixedly connected to corresponding guide plates (6) in a symmetrical manner on both sides, and the distance between the end portions of the two guide plates (6) installed on two adjacent partition plates (5) and arranged opposite to each other gradually decreases, and the return flow receiving member (4) located between the two guide plates (6) installed on the same partition plate (5) is provided with a conducting hole (7) passing through the upper and lower parts thereof, and the middle part of the return flow receiving member (4) is formed with a corresponding receiving groove (8) downwardly; An adjusting and fixing mechanism (9) is used to movably install the lower crucible body (203) up and down, and the lower crucible body (203) is used to fix the upper crucible body (201) and the middle crucible body (202) after being moved upward to a position, and the upper crucible body (201), the middle crucible body (202) and the lower crucible body (203) are sequentially abutted, tightened and sealed to form the recovery crucible (2); A vacuum unit (10), wherein a corresponding air guide pipe (11) is fixedly installed on the top of the heat-insulating furnace box (1), one end of the air guide pipe (11) extends into the heat-insulating furnace box (1) and its end abuts against the middle of the dome of the upper crucible body (201), and the other end is connected to the outside and to the vacuum unit (10) through corresponding three-way pipes and valves; The heating mechanism (12) comprises an upper heating element (1201) and a lower heating element (1202) which are arranged at an upper and lower interval and fixed to the inner side wall of the heat-insulating furnace box (1), wherein the upper heating element (1201) is used to perform high-temperature heating and distillation on the substance in the high-temperature distillation zone, and the lower heating element (1202) is used to perform low-temperature heating and distillation on the substance in the low-temperature distillation zone; A chlorine gas absorption mechanism (3) is installed in the air guide pipe (11) and is used for gradingly absorbing the chlorine gas discharged from the recovery crucible (2) or is installed at the end of the air guide pipe (11) to collect the chlorine gas discharged from the recovery crucible (2).

2. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: The adjusting and fixing mechanism (9) comprises a sleeve member (901) fixedly connected to the bottom of the lower crucible body (203) and a stud (902) fixedly installed at the inner bottom of the heat-insulating furnace box (1), and the inner wall of the sleeve member (901) is evenly distributed with internal threads that are compatible with the stud (902); the lower crucible body (203) is fixedly installed in the heat-insulating furnace box (1) by screwing the sleeve member (901) to the stud (902), and the upper crucible body (201), the middle crucible body (202) and the lower crucible body (203) are tightened, fixed and sealed by rotating the sleeve member (901) upwards to form the recovery crucible (2).

3. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: Auxiliary tightening mechanisms (13) for enhancing the installation stability of the recovery crucible (2) are provided above and below the recovery crucible (2), and the auxiliary tightening mechanism (13) comprises a plurality of support columns (1301) spaced apart and fixed to the top or bottom of the insulation furnace box (1), the support columns (1301) are distributed circumferentially with the recovery crucible (2) as the axis, and the end of the support column (1301) not connected to the insulation furnace box (1) is fixedly connected to a corresponding support ring (1303) through a corresponding elastic member (1302); after the recovery crucible (2) is installed in place, the elastic member (1302) has a movement tendency to push the support ring (1303) to press against the top or bottom of the recovery crucible (2).

4. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: The air guide pipe (11) is a water-cooled sleeve, and its air inlet section and air outlet section are respectively provided with a corresponding chlorine absorption zone (1101) and a chlorine absorption zone (1102). The chlorine absorption mechanism (3) comprises activated carbon loaded with CuCl2 filled in the chlorine absorption zone (1101) and a mixture of Ca(OH)2 and Fe2O3 filled in the chlorine absorption zone (1102).

5. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: The upper heating element (1201) and the lower heating element (1202) are both heating elements that are spirally distributed upward, and the heating element is made of high-purity graphite. The lower heating element (1202) is spirally installed on the outside of the lower crucible body (203), and the upper heating element (1201) is spirally installed on the outside of the middle crucible body (202) located at the position of the reflux receiving element (4).

6. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: A stepped exhaust hole is provided in the middle of the dome of the upper crucible body (201). When the recovery crucible (2) is installed in place, the bottom of the air guide tube (11) cooperates with a corresponding gasket to abut and be fixed on the stepped portion of the conducting hole (7) of the upper crucible body (201), and is communicated with the recovery crucible (2).

7. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: The inner side wall of the upper crucible body (201) is located at the connection with the lower crucible body (203) to form a downwardly inclined arc surface, and forms a streamlined connection with the inner side wall of the reflux receiving member (4).

8. The device for separating and recovering gold and silver from aqua regia gold slag according to claim 1, characterized in that: All side walls and closed doors of the heat-insulating furnace box (1) are sandwich structures and filled with corresponding heat-insulating materials. The heat-insulating materials are made of graphite hard felt. The diameters of the middle crucible body (202) and the lower crucible body (203) are the same. The middle crucible body (202) and the reflux receiving member (4) are made of high-purity quartz, and the lower crucible body (203) is made of high-purity graphite. The vacuum unit (10) is composed of a mechanical pump and a molecular pump, and its vacuum degree is 10 -2 ~10 -6 Pa high vacuum, further comprising a vacuum measuring device, wherein the vacuum measuring device is a high-precision vacuum gauge, and the recovery crucible (2) is further provided with a temperature measuring thermocouple for respectively detecting the middle crucible body (202) and the lower crucible body (203).

9. A method for separating and recovering gold and silver from water regia gold slag, characterized in that: The device for separating and recovering gold and silver from aqua regia gold slag according to any one of claims 1 to 8 comprises the following steps: S1, the lower crucible body (203) is fixedly installed in the heat-insulating furnace box (1), and the Regia metallurgical slag is placed in the lower crucible body (203), and the middle crucible body (202) and the upper crucible body (201) are sequentially stacked and installed on the lower crucible body (203), and the air guide tube (11) is installed above the upper crucible body (201) in abutment and communication; then, the lower crucible body (203) is moved upward and fixed by the adjusting and fixing mechanism (9), so that the upper crucible body (201), the middle crucible body (202) and the lower crucible body (203) are sequentially abutted, pressed, and sealed; S2, controlling a certain system pressure and a temperature of the low-temperature distillation zone by means of a vacuum unit (10) and a heating mechanism (12), respectively, so that the silver chloride is vaporized and volatilized upward by low-temperature distillation, while the gold remains at the inner bottom of the lower crucible body (203); S3, the vaporized silver chloride produced in step S2 evaporates upward and enters the upper crucible body (201) through the conducting hole (7) of the reflux receiving member (4), the silver chloride liquefies on the smooth dome-shaped condensation cover and flows back along the condensation cover to the surrounding edges and the inner wall of the upper crucible body (201), and is guided along the reflux receiving member (4) and gathered into the receiving groove (8) and the reflux receiving member (4); S4, after the reflux is completed, the temperature of the high-temperature distillation zone is controlled by the heating mechanism (12), and the silver chloride in the reflux receiving member (4) is decomposed into silver and chlorine in the high-temperature distillation zone by high-temperature distillation. The chlorine evaporates upward and is absorbed or collected by the chlorine absorption mechanism (3), and the silver remains in the reflux receiving member (4) and the receiving tank (8).

10. The method for separating and recovering gold and silver from aqua regia gold slag according to claim 9, characterized in that: The system pressure of the distillation process in step S2 is 10 -3 ~10 -5 Pa; the heating temperature of the low-temperature distillation zone is 750~1000℃, the time of the low-temperature distillation is 30~120min, and during the low-temperature distillation, the heating temperature of the high-temperature distillation zone is 600~750℃, the heating temperature of the high-temperature distillation zone in step S3 is 1100~1300℃, and the time of the high-temperature distillation is 30~120min.

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