Zero-discharge equipment and process for electroplating cyanide-containing wastewater

Abstract

The invention discloses zero-discharge equipment and process for electroplating cyanide-containing wastewater, relates to the technical field of electroplating cyanide-containing wastewater discharge, and aims to solve the technical problem of insufficient functions of an aeration device. The zero-discharge equipment comprises an electroplating cyanide-containing wastewater pretreatment box body; an aeration pump feeder is arranged on one side of the top of the electroplating cyanide-containing wastewater pretreatment box body; a pump machine for conveying is arranged on one side of the aeration pump machine; a plurality of aeration systems are sequentially arranged at the top of the electroplating cyanide-containing wastewater pretreatment box body through a plurality of trusses; the aeration system comprises an aeration mechanism which is connected with the truss by connecting a hollow shaft seat; and a double-shaft motor for driving the aeration mechanism to rotate is arranged on the truss. The angle state of the aeration mechanism is adjusted to meet different requirements in the two-stage cyanide breaking reaction process, so that the diversification of the aeration function is realized, and the actual use effect of the zero-discharge aeration device for electroplating cyanide-containing wastewater is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electroplating cyanide-containing wastewater discharge, more particularly to an electroplating cyanide-containing wastewater zero-discharge device and process. BACKGROUND

[0002] The electroplating industry is an important modern processing industry, but the cyanide-containing wastewater generated in its production process is extremely toxic and must be strictly treated. The traditional cyanide-containing wastewater treatment process usually adopts the "alkaline chlorination method" for cyanide breaking treatment, and then is discharged or further subjected to biochemical treatment. However, with the increasingly stringent environmental protection requirements and the highlighting of water resource scarcity problems, realizing wastewater "zero discharge" has become an inevitable requirement for the sustainable development of electroplating enterprises.

[0003] The existing zero-discharge process route generally follows the technical path of "pretreatment + membrane concentration + evaporation crystallization". In this path, the cyanide breaking effect in the pretreatment stage is the key prerequisite for the long-term stable operation of the entire system. If the pretreatment is not thorough, the residual cyanide will poison the subsequent reverse osmosis membrane, causing irreversible damage to the membrane element, and eventually causing the blockage and corrosion of the evaporation crystallization system, resulting in the paralysis of the entire zero-discharge system.

[0004] At present, the cyanide breaking reaction in the pretreatment stage mainly relies on the traditional aeration stirring system. Such system usually has the following inherent defects: Uneven mixing and reaction dead angle: The traditional aeration or stirring method is difficult to form a completely uniform flow field in the reaction tank, and is easy to form "dead zones" at the bottom and corners of the tank. This leads to insufficient mixing of the added reagents (such as NaOH, NaClO) with wastewater, insufficient concentration of reaction substances in local areas, and incomplete cyanide breaking reaction.

[0005] Precipitate accumulation and treatment efficiency decay: A large amount of heavy metal hydroxide precipitate is produced in the cyanide breaking and subsequent neutralization processes. The traditional system has insufficient scouring force on the tank bottom, and the precipitate is easy to accumulate and harden on the tank bottom. These precipitates not only wrap the unreacted cyanide to form a treatment dead angle, but also greatly reduce the effective volume of the reaction tank, leading to a reduction in hydraulic retention time and a gradual decay of treatment efficiency with running time.

[0006] Single function and poor adaptability: The cyanide breaking process involves multiple reagent dosing (such as adding NaOH to adjust the alkali, and then adding NaClO for oxidation), and the requirements for mixing intensity and flow field characteristics are different at different stages. However, the traditional aeration system has a single function and cannot intelligently adapt to the requirements of different process stages, making it difficult to achieve optimal control of the process.

[0007] In view of this, how to overcome the functional deficiencies of the existing aeration device, provide a zero discharge aeration device for electroplating cyanide-containing wastewater, which can intelligently adapt to the requirements of each stage of cyanide breaking process, completely eliminate reaction dead angles and sediment accumulation, and ensure that the cyanide breaking reaction is always efficient and thorough, thereby providing stable and reliable water for the subsequent membrane treatment and evaporation crystallization system, is particularly important. Therefore, we propose a zero discharge device and process for electroplating cyanide-containing wastewater. SUMMARY

[0008] The purpose of the present application is to provide a zero discharge device and process for electroplating cyanide-containing wastewater to solve the technical problem of the functional deficiency of the aeration device.

[0009] To solve the above technical problems, the present application provides the following technical scheme: a zero discharge device and process for electroplating cyanide-containing wastewater, comprising an electroplating cyanide-containing wastewater pretreatment box; an aeration pump feeding machine is arranged on one side of the top of the electroplating cyanide-containing wastewater pretreatment box; a pump machine for conveying is arranged on one side of the aeration pump feeding machine; a plurality of aeration systems are arranged on the top of the electroplating cyanide-containing wastewater pretreatment box in sequence through a plurality of trusses; the aeration system comprises an aeration mechanism connected to the truss through a connecting hollow shaft seat; a double-shaft motor for driving the aeration mechanism to rotate is arranged on the truss; an auxiliary guide block is arranged at the bottom of the electroplating cyanide-containing wastewater pretreatment box; the aeration mechanism has a horizontal state and a vertical state.

[0010] The present application adjusts the angle state of the aeration mechanism to meet the different needs in the two-stage cyanide breaking reaction process, thereby realizing the diversification of the aeration function and further improving the actual use effect of the zero discharge aeration device for electroplating cyanide-containing wastewater.

[0011] Preferably, the aeration system comprises a planetary drive mechanism arranged at the bottom of the truss; the planetary drive mechanism comprises a double-gear drive disc rotatably arranged in the connecting hollow shaft seat, and the double-gear drive disc is provided with an auxiliary driving tooth on the edge; a planet carrier is movably arranged inside the double-gear drive disc; a plurality of planetary gears are arranged on the planet carrier in a ring shape at equal intervals, wherein a center driving gear is rotatably arranged at the middle end of the planet carrier, and the center driving gear is provided with a meshing bevel gear; wherein the connecting hollow shaft seat is respectively provided with a first driving shaft and a second driving shaft; the end of the first driving shaft is provided with an auxiliary driving gear for driving the double-gear drive disc to rotate; the end of the second driving shaft is provided with a meshing driving gear for driving the meshing bevel gear to rotate.

[0012] Preferably, the aeration system further comprises a main aeration shaft rotatably arranged at the end of the connecting hollow shaft; the main aeration shaft is connected to the planetary carrier; a crank is rotatably arranged in the main aeration shaft; the crank is connected to the central drive gear; the central drive gear is internally provided with an aeration conveying channel; and the aeration conveying channel is connected to the shunt channel of the crank.

[0013] Preferably, the crank is hingedly provided with two main drive piston shafts at the middle end; at least one one-way valve is arranged on the main drive piston shaft; a compression pump cavity is arranged on the main aeration shaft relative to the axial position of the main drive piston shaft; a communication cavity is arranged on the two sides of the compression pump cavity in the radial direction; and a uniform distribution cavity is arranged on the inner wall of the main aeration shaft and connected to the communication cavity.

[0014] Preferably, two opposite drive connecting rod shafts are hingedly arranged on both sides of the crank; the two opposite drive connecting rod shafts on one side are connected through a synchronization block; and a multi-stage telescopic mechanism is hingedly arranged at the end of the synchronization block.

[0015] Preferably, the multi-stage telescopic mechanism comprises a main piston shaft sleeve hingedly arranged at the end of the synchronization block; a multi-stage drive main shaft is rotatably arranged at the center of the main piston shaft sleeve; a two-stage telescopic sleeve is arranged inside the main piston shaft sleeve and connected by a key; the two-stage telescopic sleeve and the multi-stage drive main shaft are in cam structure; a two-stage drive sleeve is arranged outside the main piston shaft sleeve relative to the inside of the two-stage telescopic sleeve; a three-stage telescopic sleeve is arranged inside the two-stage telescopic sleeve and connected to the two-stage drive sleeve by a key; a three-stage drive sleeve is arranged outside the two-stage drive sleeve relative to the inside of the three-stage telescopic sleeve; and a four-stage telescopic sleeve is arranged on the outer wall of the three-stage drive sleeve.

[0016] Preferably, the main piston shaft sleeve, the two-stage telescopic sleeve, the three-stage telescopic sleeve, and the four-stage telescopic sleeve are telescopic sleeves, and are nested layer by layer, and the two adjacent telescopic sleeves are connected by a key; the main piston shaft sleeve and the multi-stage drive main shaft are connected by a hooking rotation structure; the two-stage telescopic sleeve and the two-stage drive sleeve are connected by a hooking rotation structure; the three-stage telescopic sleeve and the three-stage drive sleeve are connected by a hooking rotation structure; and the multi-stage drive main shaft, the two-stage drive sleeve, and the three-stage drive sleeve are drive sleeves, and are nested layer by layer, and the two adjacent drive sleeves are connected by a key.

[0017] Preferably, the multi-stage driving main shaft is provided with a driving groove relative to the end surface of the crank; the driving groove is composed of a spiral driving extrusion groove and a linear structure fitting groove; the multi-stage driving main shaft is provided with a rotating driving shaft sleeve relative to the position of the driving groove, and the inner wall of the rotating driving shaft sleeve is provided with an extrusion protrusion; in the vertical state, the rotating driving shaft sleeve located on the upper side is fixedly connected with the main aeration shaft through a connecting shaft; the rotating driving shaft sleeve located on the lower side is key-connected with the main aeration shaft through a connecting shaft; and the rotating driving shaft sleeve located on the lower side is elastically connected with the main aeration shaft through a spring.

[0018] Preferably, in the horizontal state, the two groups of multi-stage telescopic mechanisms and the two groups of main driving piston shafts are relatively close to each other for the same amount of air pumping; in the vertical state, the multi-stage telescopic mechanism located on the upper side and the main driving piston shaft are relatively close to each other for the amount of air pumping, which is less than that of the multi-stage telescopic mechanism located on the lower side and the main driving piston shaft.

[0019] A zero-emission process for electroplating cyanide-containing wastewater, comprising the following steps: S100, wastewater homogenization: the cyanide-containing wastewater first removes large particles of suspended solids through a grid, and then enters a conditioning tank for homogenization and equalization of water quantity and quality to create conditions for subsequent stable treatment; S200, two-stage cyanide-breaking oxidation pretreatment: this is the core link of the process, which utilizes the two aeration states of the device and precisely cooperates with three reagent dosing: S201, first dosing and mixing: sodium hydroxide (NaOH) is dosed into the pretreatment tank to adjust the pH to 10-11; at this time, the aeration mechanism is controlled to be in a horizontal state for symmetrical and uniform aeration to realize rapid dispersion and mixing of NaOH and create a uniform alkaline environment for oxidation reaction; S202, second dosing and first-stage cyanide breaking: sodium hypochlorite (NaClO) is dosed for first-stage cyanide breaking to oxidize cyanide to cyanate; this stage maintains horizontal state aeration to maintain a stable flow field environment to ensure efficient and uniform oxidation reaction; S203, state switching, third dosing and second-stage cyanide breaking: sodium hypochlorite (NaClO) is dosed for second-stage cyanide breaking, and the pH is adjusted to 7-8 to completely oxidize cyanate to and Meanwhile, heavy metal ions begin to form hydroxide precipitates; at this stage, the aeration mechanism is switched to a vertical state; by utilizing the asymmetric aeration characteristic that the air volume at the bottom is much larger than that at the top, a powerful directional uplift flow is generated; S300, solid-liquid separation: the pretreated wastewater enters the solid-liquid separation stage; first, the suspended hydroxide precipitate is pressed into a mud cake by a filter press and is transported out; the clear liquid enters an ultrafiltration system to further remove colloids, macromolecular organic matter and the like; S400, membrane concentration and reuse: the ultrafiltration water enters a three-stage reverse osmosis system; the reverse osmosis water (fresh water, conductivity < 5 muS / cm) can be directly reused in the electroplating production line to realize water resource recovery; S500, evaporation crystallization and final disposal: the concentrated water produced by reverse osmosis enters an evaporator (such as an MVR evaporator) for evaporation and concentration, and the water is condensed and returned to the front end of the system; the dissolved salt is crystallized and separated out as solid waste and is transported out, and finally zero liquid discharge of wastewater is realized.

[0020] Compared with the prior art, the beneficial effects of the present application are: 1. The present application adjusts the angle state of the aeration mechanism to meet the different needs in the two-stage cyanide breaking reaction process, thereby realizing the diversification of the aeration function and further improving the actual use effect of the zero discharge aeration device for electroplating cyanide-containing wastewater.

[0021] 2. The double-shaft motor drives the primary drive shaft and the secondary drive shaft to rotate, and the double-shaft motor is a combination of two motors, one of which passes through the output shaft of the other motor and is coaxially arranged. The primary drive shaft is controlled to rotate or be locked to control the double gear driving disc to rotate or be locked, thereby achieving vertical or horizontal adjustment of the aeration mechanism.

[0022] 3. The uniform distribution cavity is arranged to uniformly aerate the electroplating cyanide-containing wastewater during pretreatment, effectively increases the gas and electroplating cyanide-containing wastewater removal area, and improves the aeration effect.

[0023] 4. The present application forms an extended piston mechanism through the arrangement of the multi-stage telescopic mechanism, thereby improving the gas pumping amount and improving the aeration treatment effect; and further increasing the axial distance of the main aeration shaft to effectively improve the gas distribution effect.

[0024] 5. The present application changes the traditional screw rotation and performs multi-stage telescoping through cam extrusion, which effectively reduces the number of rotations compared with the traditional operation, effectively adapts the linkage of the pump drive, and reduces the preparation cost.

[0025] 6. The present application realizes the rotation adjustment of the main aeration shaft through the revolution of the planetary drive mechanism, drives the rotation of the crank through the center output of the planetary drive mechanism, realizes the required power output of two kinds, and simultaneously realizes the hooking of the round head end of the rotation drive shaft sleeve on the lower side with the auxiliary guide block when the main aeration shaft is adjusted from horizontal to vertical state. Figure 3The rotation driving shaft sleeve is synchronously stretched by the arc-shaped guide of the auxiliary guide block, so that the rotation driving shaft sleeve moves outward as a whole, and the lower extrusion protrusion is adjusted from the starting end of the fitting groove to the connecting position of the fitting groove and the driving extrusion groove, through the setting, the aeration movement of the main aeration shaft on the upper side is relatively soft, the gas amount is small, and the pumping amplitude is small during the rotation of the crank; the aeration movement of the main aeration shaft on the upper side is relatively large in impact degree, the gas amount is relatively large, and the pumping amplitude is large, and differential pumping work is formed; based on the elastic force of the spring in the horizontal state, the rotation driving shaft sleeves on the two sides are relatively kept consistent, and the aeration effects on the two sides of the main aeration shaft are consistent; through the intelligent switching of the aeration mechanism between the horizontal and vertical states, precise adaptation to the process requirements of three times of reagent addition (sodium hydroxide, sodium hypochlorite and sodium hypochlorite) is realized: the horizontal state is served for the rapid and uniform mixing of the first time of reagent addition (sodium hydroxide) and the efficient primary cyanide breaking of the second time of reagent addition (sodium hypochlorite) in turn due to the symmetrical and uniform aeration characteristics, so that the uniformity and stability of the reaction environment are ensured; and the vertical state is specially used for the deep oxidation and neutralization and precipitation stages after the third time of reagent addition (sodium hypochlorite) through the directional lifting flow generated by the asymmetric aeration (large gas amount), so that the mass transfer efficiency of the slow reaction is keyly strengthened, and the heavy metal hydroxide is effectively prevented from being solidified on the pool bottom, thereby realizing the whole-process optimization from rapid start, stable reaction to thorough purification and obstacle removal for downstream filtration, laying a solid foundation for the efficient, stable and zero-emission process. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a whole three-dimensional structure schematic diagram of the application.

[0027] Figure 2 It is a three-dimensional structure schematic diagram of the inside of the electroplating cyanide-containing wastewater pretreatment box body of the application.

[0028] Figure 3 It is a front view structure schematic diagram of the inside of the electroplating cyanide-containing wastewater pretreatment box body of the application.

[0029] Figure 4 It is a three-dimensional structure schematic diagram of the installation of the connecting hollow shaft seat of the application.

[0030] Figure 5 It is a three-dimensional structure schematic diagram of the planetary drive mechanism of the application.

[0031] Figure 6 It is a cross-sectional three-dimensional structure schematic diagram of the aeration mechanism of the application.

[0032] Figure 7 It is a top view structure schematic diagram of the inside of the aeration mechanism of the application.

[0033] Figure 8 It is a three-dimensional split structure schematic diagram of the multi-stage telescopic mechanism of the application.

[0034] Figure 9 This is a three-dimensional cross-sectional structural diagram of the multi-stage telescopic mechanism of the present invention.

[0035] Figure 10 This is a three-dimensional structural diagram of the rotary drive bushing and multi-stage drive spindle of the present invention.

[0036] Explanation of the numbers in the diagram: 1. Pretreatment tank for electroplating cyanide-containing wastewater; 2. Aeration pump; 3. Pump; 4. Aeration system; 5. Connecting hollow shaft seat; 6. Aeration mechanism; 7. Dual-shaft motor; 8. Auxiliary guide block; 9. Planetary drive mechanism; 901. Dual-gear drive disc; 9011. Auxiliary drive gear; 902. Planetary carrier; 903. Central drive gear; 9031. Meshing bevel gear; 904. Primary drive shaft; 9041. Auxiliary drive gear; 905. Secondary drive shaft; 9051. Meshing drive gear 10. Wheel; 11. Main aeration shaft; 12. Crank; 13. Main drive piston shaft; 14. Opposite drive connecting rod shaft; 15. Multi-stage telescopic mechanism; 16. Main piston bushing; 17. Multi-stage drive main shaft; 18. Drive groove; 19. Drive extrusion groove; 10. Adaptor groove; 11. Secondary telescopic bushing; 12. Secondary drive bushing; 12. Third-stage telescopic bushing; 12. Fourth-stage telescopic bushing; 13. Rotation drive bushing. Detailed Implementation

[0037] like Figures 1 to 10 As shown, this invention relates to a zero-discharge device for electroplating cyanide-containing wastewater, comprising an electroplating cyanide-containing wastewater pretreatment tank 1; an aeration pump 2 is installed on one side of the top of the electroplating cyanide-containing wastewater pretreatment tank 1; a pump 3 for conveying is installed on one side of the aeration pump 2; several aeration systems 4 are sequentially arranged on the top of the electroplating cyanide-containing wastewater pretreatment tank 1 via several trusses; each aeration system 4 includes an aeration mechanism 6 connected to the trusses via a hollow shaft seat 5; a dual-shaft motor 7 for driving the rotation of the aeration mechanism 6 is installed on the trusses; an auxiliary guide block 8 is installed at the bottom of the electroplating cyanide-containing wastewater pretreatment tank 1; the aeration mechanism 6 has a horizontal state and a vertical state. This invention achieves diversified aeration functions by adjusting the angle of the aeration mechanism 6 to meet different needs in the two-stage cyanide-breaking reaction process, thereby further improving the actual performance of the zero-discharge aeration device for electroplating cyanide-containing wastewater.

[0038] In the embodiment of the present application, the aeration system 4 comprises a planetary drive mechanism 9 arranged at the bottom of the truss; the planetary drive mechanism 9 comprises a double gear driving disc 901 rotatably arranged in the connecting hollow shaft base 5, and the double gear driving disc 901 is provided with auxiliary driving teeth 9011 at the edge; a planet carrier 902 is movably arranged inside the double gear driving disc 901; a plurality of planetary gears are arranged in a ring shape at equal intervals on the planet carrier 902, wherein a central driving gear 903 is rotatably arranged at the middle end of the planet carrier 902, and the central driving gear 903 is provided with a meshing bevel gear 9031; wherein the connecting hollow shaft base 5 is provided with a primary driving shaft 904 and a secondary driving shaft 905, respectively; the end of the primary driving shaft 904 is provided with an auxiliary driving gear 9041 for driving the double gear driving disc 901 to rotate; and the end of the secondary driving shaft 905 is provided with a meshing driving gear 9051 for driving the meshing bevel gear 9031 to rotate. In the present application, the double-shaft motor 7 drives the primary driving shaft 904 and the secondary driving shaft 905 to rotate, and the double-shaft motor is a combination of two motors, wherein one motor output shaft penetrates through the output shaft of the other motor, and they are coaxially arranged; the rotation or locking of the double gear driving disc 901 is controlled by controlling the rotation or locking of the primary driving shaft 904, so as to realize the vertical or horizontal adjustment of the aeration mechanism 6.

[0039] In the embodiment of the present application, the aeration system 4 further comprises a main aeration shaft 10 rotatably arranged at the end of the connecting hollow shaft base 5; the main aeration shaft 10 is connected to the planet carrier 902 in a plug-in manner; a crank 11 is rotatably arranged at the middle end of the main aeration shaft 10; the crank 11 is connected to the central driving gear 903 in a plug-in manner, and the central driving gear 903 is internally provided with an aeration conveying passage, and the aeration conveying passage is in communication with the shunt passage of the crank 11.

[0040] In the embodiment of the present application, the crank 11 is hingedly provided with two main driving piston shafts 1101 at the middle end; at least one one-way valve is arranged on the main driving piston shaft 1101; a compression pump cavity is arranged on the main aeration shaft 10 in the axial position of the main driving piston shaft 1101; a communication cavity is arranged on the two sides of the compression pump cavity in a radial direction; and a uniform distribution cavity is arranged on the inner wall of the main aeration shaft 10 and is in communication with the communication cavity. The arrangement of the uniform distribution cavity can form the effect of uniform aeration in the pretreatment of electroplating cyanide-containing wastewater, and can effectively increase the gas and electroplating cyanide-containing wastewater removal area and improve the aeration effect.

[0041] In the embodiment of the present application, two opposite driving connecting rod shafts 1102 are respectively hingedly arranged on both sides of the crank 11; the two opposite driving connecting rod shafts 1102 on one side are connected through a synchronous block, and a multi-stage telescopic mechanism 12 is hingedly arranged at the end of the synchronous block. The multi-stage telescopic mechanism 12 is arranged to form an extended piston mechanism, which improves the gas pumping capacity and improves the aeration treatment effect; and further increases the axial distance of the main aeration shaft 10 to improve the uniform distribution effect of the pumped gas.

[0042] In the embodiment of the present application, the multi-stage telescopic mechanism 12 comprises a main piston shaft sleeve 1201 hingedly arranged at the end of the synchronous block; a multi-stage driving main shaft 1202 is rotatably arranged at the shaft center of the main piston shaft sleeve 1201; a two-stage telescopic shaft sleeve 1203 is key-connectedly arranged inside the main piston shaft sleeve 1201; the two-stage telescopic shaft sleeve 1203 and the multi-stage driving main shaft 1202 are in cam structure; a two-stage driving shaft sleeve 1204 is arranged outside the main piston shaft sleeve 1201 relative to the inside of the two-stage telescopic shaft sleeve 1203; a three-stage telescopic shaft sleeve 1205 is key-connectedly arranged inside the two-stage telescopic shaft sleeve 1203 and is in extrusion fit with the two-stage driving shaft sleeve 1204; a three-stage driving shaft sleeve 1206 is arranged outside the two-stage driving shaft sleeve 1204 relative to the inside of the three-stage telescopic shaft sleeve 1205; and a four-stage telescopic shaft sleeve 1207 is arranged on the outer wall of the three-stage driving shaft sleeve 1206. The multi-stage telescopic mechanism 12 changes the traditional screw rotation and realizes multi-stage telescoping through cam extrusion, effectively reduces the number of rotation operations compared with the traditional operation, effectively adapts the linkage of the pump transmission, and reduces the preparation cost.

[0043] In the embodiment of the present application, the main piston shaft sleeve 1201, the two-stage telescopic shaft sleeve 1203, the three-stage telescopic shaft sleeve 1205, and the four-stage telescopic shaft sleeve 1207 are telescopic shaft sleeves, and are nested layer by layer, and the two adjacent telescopic shaft sleeves are key-connected; the main piston shaft sleeve 1201 and the multi-stage driving main shaft 1202 are in hook-connection rotation structure; the two-stage telescopic shaft sleeve 1203 and the two-stage driving shaft sleeve 1204 are in hook-connection rotation structure; the three-stage telescopic shaft sleeve 1205 and the three-stage driving shaft sleeve 1206 are in hook-connection rotation structure; and the multi-stage driving main shaft 1202, the two-stage driving shaft sleeve 1204, and the three-stage driving shaft sleeve 1206 are driving shaft sleeves, and are nested layer by layer, and the two adjacent driving shaft sleeves are key-connected.

[0044] In the embodiment of the present application, the multi-stage driving main shaft 1202 is provided with a driving groove 12021 at one end surface away from the crank 11; the driving groove 12021 is composed of a driving extrusion groove 12022 in a spiral shape and an adaptive groove 12023 in a straight line structure; the multi-stage driving main shaft 1202 is provided with a rotating driving shaft sleeve 13 at the position of the driving groove 12021, and the inner wall of the rotating driving shaft sleeve 13 is provided with an extrusion protrusion; in the vertical state, the rotating driving shaft sleeve 13 on the upper side is fixedly connected with the main aeration shaft 10 through a connecting shaft; the rotating driving shaft sleeve 13 on the lower side is key-connected with the main aeration shaft 10 through a connecting shaft; and the rotating driving shaft sleeve 13 on the lower side is elastically connected with the main aeration shaft 10 through a spring.

[0045] In the embodiment of the present application, in the horizontal state, two groups of multi-stage telescopic mechanisms 12 and two groups of main driving piston shafts 1101 are relatively close to each other to pump out the same amount of gas; in the vertical state, the multi-stage telescopic mechanism 12 on the upper side and the main driving piston shaft 1101 are relatively close to each other to pump out a smaller amount of gas than the multi-stage telescopic mechanism 12 on the lower side and the main driving piston shaft 1101. The present application realizes the rotation adjustment of the main aeration shaft 10 through the revolution of the planetary driving mechanism 9, and drives the rotation of the crank 11 through the center output of the planetary driving mechanism 9, so as to realize the required two kinds of power output; at the same time, based on the adjustment of the main aeration shaft 10 from the horizontal state to the vertical state, the rotating driving shaft sleeve 13 on the lower side is hooked with the auxiliary guide block 8 through the round head end, and the crank 11 is driven to rotate through the planetary driving mechanism 9, so as to realize the required two kinds of power output. Figure 3The rotation driving shaft sleeve 13 is synchronously stretched by the arc-shaped guide through the auxiliary guide block 8, so that the rotation driving shaft sleeve 13 moves outward as a whole, and the lower extrusion protrusion is adjusted from the starting end of the adaptive groove 12023 to the connecting position of the adaptive groove 12023 and the driving extrusion groove 12022. Through the setting, the aeration movement of the main aeration shaft 10 is relatively soft on the upper side in the rotation of the crank 11, the gas amount is small, and the pumping amplitude is small; the aeration movement of the main aeration shaft 10 is relatively high in impact degree on the upper side, the gas amount is relatively large, and the pumping amplitude is large, forming differentiated pumping work; in the horizontal state, the elastic force of the spring causes the rotation driving shaft sleeves 13 on both sides to be consistent, so that the aeration effects on both sides of the main aeration shaft 10 are consistent; the intelligent switching of the aeration mechanism of the application between the horizontal and vertical states realizes precise adaptation to the process requirements of three times of reagent addition of sodium hydroxide, sodium hypochlorite and sodium hypochlorite: the horizontal state is served for the rapid and uniform mixing of the first addition of sodium hydroxide and the efficient primary cyanide breaking of the second addition of sodium hypochlorite in sequence due to the symmetrical and uniform aeration characteristics, so that the uniformity and stability of the reaction environment are ensured; and the vertical state is specially used for the deep oxidation and neutralization and precipitation stages after the third addition of sodium hypochlorite through the directional lifting flow generated by the large gas amount of the asymmetric aeration, so that the mass transfer efficiency of the slow reaction is keyly strengthened, and the heavy metal hydroxide is effectively prevented from being solidified on the pool bottom, thereby realizing the whole process optimization from rapid start, stable reaction to complete purification and obstacle removal for downstream filtration, and laying a solid foundation for the efficient, stable and zero-emission process.

[0046] Working principle: the embodiment provides a zero-emission process for electroplating cyanide-containing wastewater, and uses the following steps: S100, wastewater homogenization: the cyanide-containing wastewater first removes large particle suspensions through a grid, and then enters an adjusting tank for homogenization and equalization adjustment of water quantity and water quality, so as to create conditions for subsequent stable treatment; S200, two-stage cyanide breaking and oxidation pretreatment: this is the core link of the process, and the two aeration states of the device are used to precisely cooperate with three times of reagent addition: S201, first addition and mixing: sodium hydroxide NaOH is added to the pretreatment box, and the pH is adjusted to 10-11; at this time, the aeration mechanism is controlled to be in a horizontal state, symmetrical and uniform aeration is performed, rapid dispersion and mixing of NaOH are realized, and a uniform strong alkaline environment is created for the oxidation reaction; S202, second addition and primary cyanide breaking: sodium hypochlorite NaClO is added for primary cyanide breaking, and cyanide is oxidized into cyanate; the horizontal state is maintained during this stage, a stable flow field environment is maintained, and the oxidation reaction is ensured to be efficient and uniform; S203, state switching, third addition and secondary cyanide breaking: sodium hypochlorite NaClO is added for secondary cyanide breaking, and the pH is adjusted to 7-8, so that cyanate is completely oxidized into and At the same time, heavy metal ions begin to form hydroxide precipitates; at this stage, the aeration mechanism is switched to a vertical state; taking advantage of its asymmetric aeration characteristic that the air volume at the bottom is much greater than that at the top, a powerful directional lifting flow is generated; (Function 1: Enhanced Oxidation: Strong bottom disturbance greatly enhances mass transfer efficiency, promoting the slow secondary oxidation reaction to near completion; Function 2: Prevents Cementation: The strong bottom flushing force acts directly on the bottom of the tank, effectively preventing hydroxide precipitates from accumulating and caking, keeping them in suspension, and creating optimal conditions for subsequent solid-liquid separation.) S300, Solid-Liquid Separation: The pretreated wastewater enters the solid-liquid separation stage; firstly, the suspended hydroxides are precipitated and filtered into sludge cakes by a filter press and transported off-site; the clear liquid then enters the ultrafiltration system to further remove colloids, macromolecular organic matter, etc. S400, Membrane Concentration and Reuse: Ultrafiltration permeate enters the three-stage reverse osmosis system; Reverse osmosis permeate, with a conductivity of <5μS / cm, can be directly reused in the electroplating production line, realizing water resource recovery; S500, Evaporation Crystallization and Final Disposal: The concentrated water produced by reverse osmosis enters an evaporator such as an MVR evaporator for evaporation and concentration. After the water is condensed, it is returned to the front end of the system. The dissolved salts crystallize out and are transported off-site as solid waste, ultimately achieving zero liquid discharge of wastewater. S600 Intelligent Control: Throughout the treatment process, water quality is monitored in real time through online monitoring instruments such as pH, ORP, cyanide, and turbidity. The automated control system PLC automatically adjusts the dosage of chemicals, the timing of aeration state switching, and equipment operating parameters based on feedback signals to ensure a stable and compliant treatment process.

[0047] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A zero-discharge device for electroplating wastewater containing cyanide, characterized in that, It includes a pretreatment tank (1) for electroplating cyanide-containing wastewater; an aeration pump feeder (2) is provided on one side of the top of the pretreatment tank (1); and a pump (3) for conveying is provided on one side of the aeration pump feeder (2). The top of the electroplating cyanide-containing wastewater pretreatment tank (1) is equipped with several aeration systems (4) arranged in sequence through several trusses. The aeration system (4) includes an aeration mechanism (6) connected to the truss via a connecting hollow shaft seat (5); the truss is provided with a dual-axis motor (7) for driving the aeration mechanism (6) to rotate. The bottom of the electroplating cyanide-containing wastewater pretreatment tank (1) is provided with an auxiliary guide block (8); The aeration mechanism (6) has a horizontal state and a vertical state.

2. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 1, characterized in that, The aeration system (4) includes a planetary drive mechanism (9) arranged at the bottom of the truss; the planetary drive mechanism (9) includes a double gear drive disk (901) rotatably arranged in the connecting hollow shaft seat (5), and the double gear drive disk (901) is provided with auxiliary drive teeth (9011) on its edge; a planet carrier (902) is movably arranged inside the double gear drive disk (901); a plurality of planetary gears are arranged in a ring at equal intervals on the planet carrier (902), wherein a central drive gear (903) is rotatably arranged at the middle end of the planet carrier (902), and the central drive gear (903) is provided with a meshing bevel gear (9031). The hollow connecting shaft seat (5) is provided with a primary drive shaft (904) and a secondary drive shaft (905); the end of the primary drive shaft (904) is provided with an auxiliary drive gear (9041) for driving the double gear drive disk (901) to rotate; the end of the secondary drive shaft (905) is provided with a meshing drive gear (9051) for driving the meshing bevel gear (9031) to rotate.

3. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 2, characterized in that, The aeration system (4) further includes a main aeration shaft (10) rotatably arranged at the end of the connecting hollow shaft seat (5); the main aeration shaft (10) is plugged into the planetary frame (902); a crank (11) is rotatably provided at the middle end of the main aeration shaft (10); the crank (11) is plugged into the central drive gear (903), and the central drive gear (903) is provided with an aeration conveying channel inside, and the aeration conveying channel is connected to the diversion channel of the crank (11).

4. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 3, characterized in that, Two main drive piston shafts (1101) are hinged at the middle end of the crank (11); at least one check valve is provided on the main drive piston shaft (1101); The main aeration shaft (10) is provided with a compression pump outlet chamber at an axial position relative to the main drive piston shaft (1101); the compression pump outlet chamber is provided with communicating chambers on both radial sides; the inner wall of the main aeration shaft (10) is provided with uniformly distributed chambers communicating with the communicating chambers.

5. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 4, characterized in that, Two opposing drive linkage shafts (1102) are respectively hinged on both sides of the crank (11); wherein, the two opposing drive linkage shafts (1102) located on one side are connected by a synchronizing block, and a multi-stage telescopic mechanism (12) is hinged at the end of the synchronizing block.

6. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 5, characterized in that, The multi-stage telescopic mechanism (12) includes a main piston bushing (1201) hinged to the end of the synchronizing block; a multi-stage drive main shaft (1202) is rotatably arranged at the axis of the main piston bushing (1201); a secondary telescopic bushing (1203) is keyed inside the main piston bushing (1201); a cam structure is formed between the secondary telescopic bushing (1203) and the multi-stage drive main shaft (1202); A secondary drive bushing (1204) is provided outside the main piston bushing (1201) and inside the secondary telescopic bushing (1203); a tertiary telescopic bushing (1205) is keyed inside the secondary telescopic bushing (1203) and is in compression fit with the secondary drive bushing (1204). A third-stage drive bushing (1206) is provided on the outside of the second-stage drive bushing (1204) relative to the inside of the third-stage telescopic bushing (1205). The outer wall of the three-stage drive bushing (1206) is provided with a four-stage telescopic bushing (1207).

7. A zero-discharge device for electroplating cyanide-containing wastewater according to claim 6, characterized in that, The main piston bushing (1201), the secondary telescopic bushing (1203), the tertiary telescopic bushing (1205), and the quaternary telescopic bushing (1207) are all telescopic bushings, and they are nested in layers, and the two adjacent telescopic bushings are connected by a key. The main piston bushing (1201) and the multi-stage drive main shaft (1202) are connected by a rotating structure; The secondary telescopic bushing (1203) and the secondary drive bushing (1204) are connected by a rotating structure; The three-stage telescopic bushing (1205) and the three-stage drive bushing (1206) are connected by a rotating structure; The multi-stage drive spindle (1202), the second-stage drive bushing (1204), and the third-stage drive bushing (1206) are all drive bushings, and they are nested in layers. Furthermore, adjacent drive bushings are connected by a key.

8. The zero-discharge equipment for electroplating cyanide-containing wastewater according to claim 7, characterized in that, The multi-stage drive spindle (1202) has a drive groove (12021) on the surface of the end opposite to the crank (11); the drive groove (12021) is composed of a spiral drive extrusion groove (12022) and a straight adapter groove (12023); The multi-stage drive spindle (1202) is provided with a rotating drive bushing (13) at a position relative to the drive groove (12021), and the inner wall of the rotating drive bushing (13) is provided with extrusion protrusions; In the vertical state, the rotating drive bushing (13) located on the upper side is fixedly connected to the main aeration shaft (10) via a connecting shaft; the rotating drive bushing (13) located on the lower side is keyed to the main aeration shaft (10) via a connecting shaft; and the rotating drive bushing (13) located on the lower side is elastically connected to the main aeration shaft (10) via a spring.

9. A zero-discharge device for electroplating cyanide-containing wastewater according to claim 8, characterized in that, In a horizontal state, the two sets of multi-stage telescopic mechanisms (12) are relatively close to the two sets of main drive piston shafts (1101) to pump out the same amount of air. In the vertical state, the gas pumping volume of the multi-stage telescopic mechanism (12) located on the upper side is relatively close to the main drive piston shaft (1101) and is less than the gas pumping volume of the multi-stage telescopic mechanism (12) located on the lower side and the main drive piston shaft (1101) located relatively close to each other.

10. A zero-discharge process for cyanide-containing electroplating wastewater, applicable to the zero-discharge equipment for cyanide-containing electroplating wastewater as described in claim 9, characterized in that, Includes the following steps: S100 Wastewater homogenization: Cyanide-containing wastewater first passes through a screen to remove large suspended solids, and then enters an equalization tank for homogenization and equalization of water volume and quality, creating conditions for subsequent stable treatment. S200, two-stage cyanide oxidation pretreatment: This is the core of this process, utilizing the two aeration states of the equipment of this invention, precisely coordinated with three-stage reagent dosing: S201, First addition and mixing: Add sodium hydroxide (NaOH) to the pretreatment tank and adjust the pH to 10-11; at this time, control the aeration mechanism to be in a horizontal state, and carry out symmetrical and uniform aeration to achieve rapid dispersion and mixing of NaOH, creating a uniform strongly alkaline environment for the oxidation reaction. S202, Second Dosing and Primary Cyanide Decomposition: Sodium hypochlorite (NaClO) is added to perform primary cyanide decomposition, oxidizing cyanide to cyanate. During this stage, horizontal aeration is maintained to ensure a stable flow field environment and to ensure that the oxidation reaction proceeds efficiently and uniformly. S203, State Switching and Third Dosing and Secondary Cyanide Decomposition: Sodium hypochlorite (NaClO) is added for secondary cyanide decomposition, and the pH is adjusted to 7-8 to completely oxidize the cyanate. and At the same time, heavy metal ions begin to form hydroxide precipitates; During this stage, the aeration mechanism will be switched to a vertical position; It utilizes the asymmetric aeration characteristic that the air volume at the bottom is much greater than that at the top to generate a powerful directional lift flow; S300, Solid-Liquid Separation: The pretreated wastewater enters the solid-liquid separation stage; firstly, the suspended hydroxides are precipitated and filtered into sludge cakes by a filter press and transported off-site; the clear liquid then enters the ultrafiltration system to further remove colloids, macromolecular organic matter, etc. S400, Membrane Concentration and Reuse: Ultrafiltration permeate enters the three-stage reverse osmosis system; Reverse osmosis permeate (fresh water, conductivity <5μS / cm) can be directly reused in the electroplating production line to achieve water resource recovery; S500, Evaporation Crystallization and Final Disposal: The concentrated water produced by reverse osmosis enters the evaporator for evaporation and concentration. After the water condenses, it returns to the front end of the system. The dissolved salts crystallize out and are transported off-site as solid waste, ultimately achieving zero liquid discharge of wastewater.

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