High-salt high-organic-matter silver-containing wastewater treatment method

Abstract

The invention relates to a high-salt and high-organic-matter silver-containing wastewater treatment method. The method comprises the steps of pH value adjustment, heating, gas-phase ammonia nitrogen stripping through an ammonia stripping tower, spraying absorption through a spraying tower, water removal through a demister and organic matter filtration through an activated carbon box. Two layers of spraying packing materials of the lower packing layer are arranged in the spray tower and are piled in a continuously staggered concave-convex shape, the spray tower is shaped and fixed by a mesh enclosure with a wavy cross section, and a gas distribution plate of the upper packing layer is arranged in a wavy shape which is symmetrical to the mesh enclosure up and down; the spraying heads are connected through corrugated pipes sleeved with elastic pieces, one ends of the elastic pieces are fixedly connected with the blocking and pushing plates on the outer sides of the spraying heads, the other ends of the elastic pieces are fixed to the outer sides of the shunting branch pipes, and the spraying heads are opened and closed alternately in a staggered mode. According to the invention, gas can be transversely pushed to the periphery, so that the gas forms transverse turbulent flow and turning between the mesh enclosure and the upper-layer gas distribution plate, and then the gas flow enters the concave-convex wavy filler layer for full contact reaction, so that the contact surface between the gas and liquid is greatly increased, and the spraying effect is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a method for treating high-salt, high-organic-matter, silver-containing wastewater. Background Art

[0002] Heavy metal wastewater mainly comes from wastewater discharged by mining, smelting, electrolysis, electroplating, pesticides, medicines, paints, pigments and other enterprises. If heavy metal wastewater is not treated and directly discharged, it will seriously pollute the environment. Therefore, wastewater needs to be treated by physical, chemical or biological methods to purify wastewater, reduce pollution, and achieve wastewater recycling and reuse, so as to make full use of water resources.

[0003] In the production of silver powder, every ton of silver powder will generate 25 tons of concentrated wastewater and 20 tons of fresh wastewater. For example, if the first phase is based on 60 tons of silver powder and 300 production days, 5 tons of concentrated wastewater and 4 tons of fresh wastewater will be generated every day. Due to the high ammonia nitrogen content in concentrated wastewater and fresh wastewater, if the ammonia nitrogen is not removed in advance and is directly discharged into the silver-containing concentrated water pretreatment system (pretreatment process: pH adjustment + precipitation, in which the wastewater needs to be adjusted to weak acidity) for treatment and then discharged into the sewage station for treatment, it will not only affect or even inhibit the treatment of the silver-containing concentrated water pretreatment system, but also cause ammonia nitrogen pollution in the water body. Summary of the invention

[0004] In view of the technical problems existing in the above-mentioned prior art, the present invention provides a treatment system for silver-containing wastewater, which can effectively solve the technical problems existing in the above-mentioned prior art.

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

[0006] A method for treating high-salt, high-organic-matter silver-containing wastewater comprises the following specific steps:

[0007] S1, collecting silver-containing wastewater through a collection pool and homogenizing and averaging the amount;

[0008] S2, pumping the homogenized and weighed silver-containing wastewater into a pH adjustment tank to adjust the pH value of the silver-containing wastewater to -12;

[0009] S3, adding the pH-adjusted silver-containing wastewater into the intermediate water tank and heating it to 35°C-40°C;

[0010] S4, removing ammonia nitrogen from the heated silver-containing wastewater, including:

[0011] S41, sequentially pumping the heated silver-containing wastewater into at least one stage of ammonia stripping tower, and treating the wastewater in the ammonia stripping tower to obtain a waste gas containing gaseous ammonia nitrogen and a waste liquid free of ammonia nitrogen;

[0012] S42, using an acid- and alkali-resistant blower to blow the waste gas containing gaseous ammonia nitrogen into at least one level of spray tower for spray treatment in sequence, the spray treatment comprising: passing the waste gas containing gaseous ammonia nitrogen into the spray tower for two spray treatments from bottom to top, and in the process of the waste gas containing gaseous ammonia nitrogen flowing upward, by controlling the staggered spraying of the spray heads, the spray heads in the open state move downward under the action of the impact force of the liquid discharge, and drive the push plate fixed to the outer edge of the spray head to move downward to push the uploaded waste gas containing gaseous ammonia nitrogen downward, so that the gas flows in a horizontal distribution around; the spray heads in the closed state reset and move upward under the action of the elastic potential energy of the elastic member;

[0013] S43, the waste gas containing gaseous ammonia nitrogen from the previous spray tower is discharged to the next spray tower for reabsorption, and the waste gas after absorption by the last spray tower enters the demister to filter out excess moisture in the waste gas, and then the filtered waste gas is passed into the activated carbon box to intercept organic matter, and the treated clean gas is discharged through the chimney to meet the standards;

[0014] S5, the waste liquid free of ammonia nitrogen obtained by treatment in the ammonia stripping tower in step S41 is discharged to the silver-containing concentrated water pretreatment system.

[0015] The silver-containing wastewater in step S1 includes silver-containing concentrated water and silver-containing fresh water collected in an intermediate water tank by a corresponding wastewater collection system. The silver-containing concentrated water and silver-containing fresh water in the intermediate water tank are lifted into a collection pool by pumping.

[0016] All the waste gas containing gaseous phase ammonia nitrogen stripped by the ammonia stripping tower in step S41 and the silver-containing waste gas generated by the production line collected by the gas collecting pipeline are introduced into the spray tower in step S42 for spray absorption treatment. The gas collecting pipeline is externally connected to the waste gas discharge port of the reaction kettle and the washing kettle.

[0017] In step S5, the waste liquid from which ammonia nitrogen has been removed is first discharged into a water outlet tank for temporary storage, and then the waste liquid from which ammonia nitrogen has been removed in the water outlet tank is introduced into a silver-containing concentrated water pretreatment system by pumping, mixed with the original acidic silver-containing concentrated water, and then the pH value of the mixed liquid is adjusted to 4-6 before being discharged into a sewage station for treatment.

[0018] The ammonia nitrogen concentration in the waste liquid obtained by the step S5 is less than 2300 mg / l, the steam-water ratio of the waste gas containing gaseous ammonia nitrogen in the ammonia stripping tower is 3000:1, and the air volume of the acid-alkali resistant blower is 3500m 3 / h-4500m 3 / h; the waste gas volume generated by the reactor and the washing kettle is 700m 3 / h, the air volume of the fan connected to the gas collection pipeline is 1000m 3 / h-1500m 3 / h.

[0019] The step S42 is implemented based on a spray tower, which includes a spray tower body with an air inlet for circulating gaseous ammonia nitrogen-containing waste gas at the bottom, the spray tower body is provided with upper and lower packing layers at intervals, and a spray assembly is installed above the packing layers at intervals; the spray assembly includes a grid main pipe which is connected horizontally and vertically and fixedly installed in the spray tower body, and a plurality of spray heads which can be moved up and down are installed below the grid main pipe, the spray heads are opened and closed alternately and adjacent spray heads are opened and closed alternately, and corresponding push plates are fixedly installed on the top outer side of the spray head; the packing layer is composed of a plurality of packing materials filled on an air distribution plate, and a plurality of air permeable holes with a pore size smaller than the particle size of the packing materials are evenly distributed on the surface of the air distribution plate, the upper surface of the packing materials of the lower packing layer is stacked in a continuously staggered concave-convex shape and is fixed by a mesh cover with a wavy cross-section, and the air distribution plate of the upper packing layer is arranged to be wavy and symmetrical with the mesh cover.

[0020] Corresponding branch pipes are provided below the main grid pipe at the concave and convex positions corresponding to the mesh cover, and the branch pipes are connected to the sprinkler head via corresponding bellows. The outer side of the bellows is sleeved with elastic parts whose ends are respectively fixed to the push plate and the branch pipe.

[0021] The branch pipes are all equipped with corresponding controllable electromagnetic valves, and the controllable electromagnetic valves are used to control the opening or closing of the sprinkler heads.

[0022] The spray heads of the spray assemblies on the upper and lower layers are opened and closed alternately.

[0023] The waste gas outlet of the ammonia stripping tower is connected to the air inlet of the first spray tower through the corresponding acid-base blower and the waste gas pipe. The spray towers are connected in series, and the air outlet of the front spray tower is connected to the air inlet of the rear spray tower; the first spray tower connected to the waste gas outlet of the ammonia stripping tower is connected to the exhaust port of the production line containing ammonia waste gas through the corresponding gas collecting pipeline.

[0024] Advantages of the present invention:

[0025] 1) The present invention collects and homogenizes the collected silver-containing concentrated water and silver-containing fresh water, adds alkali to adjust the pH value to 11, heats the collected silver-containing concentrated water to 35°C-40°C, and introduces the collected silver-containing concentrated water into at least one ammonia stripping tower, strips the ammonia nitrogen in the silver-containing wastewater in the form of gas phase, and makes the ammonia nitrogen concentration of the pretreated wastewater less than 2300 mg / l. The silver-containing wastewater from which the ammonia nitrogen is removed is directly discharged into the silver-containing concentrated water pretreatment system, mixed with the original acidic silver-containing concentrated water, and the pH value is adjusted to 5 before entering the sewage station for treatment, thereby effectively avoiding the ammonia nitrogen content in the concentrated wastewater and the fresh wastewater. The high amount of waste gas will affect the treatment of the silver-containing concentrated water pretreatment system, and avoid causing ammonia nitrogen pollution to the water body; furthermore, the waste gas containing gaseous ammonia nitrogen is uniformly passed through at least one spray tower, and the gaseous ammonia nitrogen and dilute sulfuric acid liquid are contacted and reacted to the maximum extent by spraying, thereby reducing the ammonia nitrogen concentration in the water and the exhaust gas, and then enters the demister and activated carbon box in turn to filter out excess water in the waste gas and intercept organic matter in the waste gas. Finally, the treated clean gas is discharged through the chimney in compliance with the standards, so as to achieve environmental protection effects and maintain the balance of the water ecosystem.

[0026] 2) The gaseous ammonia nitrogen of the present invention enters the spray tower to react with the dilute sulfuric acid to reduce the ammonia nitrogen concentration in the gas and liquid; two layers of packing layers and two layers of spray components are arranged in the spray tower, the upper surface of the packing material of the lower packing layer is stacked in a continuous and staggered concave-convex shape, and is fixed by a mesh cover with a wavy cross-section, and the gas distribution plate of the upper packing layer is arranged in a wavy shape symmetrical with the mesh cover; and the spray head of the spray component is arranged in a one-to-one correspondence with the concave and convex position of the mesh cover, the spray head is connected to the branch pipe through a bellows, and the controllable solenoid valve is opened to control the liquid outflow. The impact force drives the sprinkler head downward, and drives the push plate fixed on the sprinkler head downward to press down the uploaded airflow, so that it is pushed and diffused laterally around; the opening and closing of the sprinkler head is set to open and close alternately, and the closed sprinkler head drives the push plate upward under the action of the elastic potential energy of the elastic part, further pushing the gas laterally around, so that the gas forms a lateral turbulence and flipping between the mesh cover and the upper air distribution plate, and then the airflow enters the concave and convex wavy filler layer for full contact reaction, greatly increasing the contact area between the gas and the liquid, and further improving the spraying effect.

[0027] 3) The spray heads of the upper and lower spray assemblies of the present invention are also opened and closed alternately. When the lower baffle plate moves up, the upper baffle plate moves down, thereby preventing the gas from rapidly diffusing upward, further controlling the gas to fully contact with the liquid to the maximum extent, and achieving the maximum removal of ammonia nitrogen.

[0028] 4) The spray head of the present invention is connected to the branch pipe through a bellows, thereby ensuring that it can move up and down; the controllable solenoid valve is opened, and the impact force of the liquid spraying drives the spray head and the push plate to move downward, and the elastic potential energy of the stretched elastic part is used to drive the closed spray head to move up and reset, so that the spray head and the push plate can be moved up and down without adding other power, thereby ensuring the practical effect of the present invention on the basis of controlling energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The present invention is a process flow chart for treating silver-containing wastewater.

[0030] Figure 2 and Figure 3 It is a schematic diagram of the installation of the spray tower in the present invention.

[0031] Figure 4 It is a schematic diagram of the cutaway structure of the spray tower in the present invention.

[0032] Figure 5 for Figure 4 Enlarged schematic diagram of part A.

[0033] Figure 6 It is a schematic diagram of the structure of the mesh cover.

[0034] Figure 7 Schematic diagram of the structure of the air distribution plate of the upper packing layer.

[0035] In the attached drawings: spray tower body 1, grid main pipe 2, spray head 3, bellows 4, air distribution plate 5, mesh cover 6, branch pipe 7, push plate 8, elastic member 9, circulating water tank 11, dosing barrel 12, demister 13, activated carbon box 14. DETAILED DESCRIPTION

[0036] 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 in conjunction with the accompanying drawings:

[0037] refer to Figure 1-7 A method for treating high-salt, high-organic-content silver-containing wastewater comprises the following specific steps:

[0038] S1, collecting silver-containing wastewater through a collection pool and homogenizing and averaging the amount;

[0039] S2, pumping the homogenized and weighed silver-containing wastewater into a pH adjustment tank to adjust the pH value of the silver-containing wastewater to -12;

[0040] S3, adding the pH-adjusted silver-containing wastewater into the intermediate water tank and heating it to 35°C-40°C;

[0041] S4, removing ammonia nitrogen from the heated silver-containing wastewater, including:

[0042] S41, sequentially pumping the heated silver-containing wastewater into at least one stage of ammonia stripping tower, and treating the wastewater in the ammonia stripping tower to obtain a waste gas containing gaseous ammonia nitrogen and a waste liquid free of ammonia nitrogen;

[0043] S42, using an acid-base resistant blower to blow the waste gas containing gaseous ammonia nitrogen into at least one level of spray tower for spray treatment, the spray treatment comprising:

[0044] The waste gas containing gaseous ammonia nitrogen is introduced into the spray tower and sprayed from bottom to top in two steps. In the process of the waste gas containing gaseous ammonia nitrogen flowing upward, the spray heads 3 are controlled to spray in a staggered manner. The spray heads in the open state move downward under the impact force of the liquid discharge, and drive the push plate 8 fixed to the outer edge of the spray head 3 to move downward to push the waste gas containing gaseous ammonia nitrogen uploaded downward, so that the gas flows in a horizontal distribution around; the spray heads 3 in the closed state are reset and moved upward under the elastic potential energy of the elastic member 9;

[0045] The spray heads 3 repeatedly open and close with delays alternately, and when the spray heads 3 are opened, the adjacent spray heads 3 are closed, and when the spray heads 3 are closed, the adjacent spray heads 3 are opened, so that the adjacent staggered opening and closing are realized, so that the spray heads 3 staggered up and down drive the connected push plates 8 to move up and down alternately, so that the exhaust gas flows horizontally to the surroundings, forming a horizontal turbulence and tumbling, and the exhaust gas is pushed downward and will enter the lower packing layer whose upper cross section is arranged in a wavy shape and fixed by the mesh cover 6 again horizontally, without affecting the exhaust gas circulation. Under the condition of increasing the contact area between the waste gas and the acidic material liquid, the purification treatment effect is improved; and a turbulent flow zone is formed between the upper packing layer and the lower packing layer, so that the waste gas and the acidic material liquid can be in maximum contact, and then the upper air distribution plate 5 with a wavy shape is arranged symmetrically with the mesh cover 6 of the lower packing layer, and the push plate 8 is driven to move upward when the spray head 3 is reset, and the upper air distribution plate 5 with a wavy cross-section is used to make the waste gas go up and be pushed horizontally around, so as to further increase the contact area between the waste gas and the acidic material liquid;

[0046] The liquid in each level of spray tower flows into the corresponding circulating water tank 11, and all the circulating water tanks 11 are connected to the dosing barrel 12 by means of pumps. Acidic materials are added to each circulating water tank 11 through the dosing barrel 12. After the circulating water tank 11 is dosed, the acidic material liquid is added to the corresponding spray tower by pumping;

[0047] S43, the waste gas containing gaseous ammonia nitrogen from the previous spray tower is discharged to the next spray tower for reabsorption, and the waste gas after absorption by the last spray tower enters the demister 13 to filter out excess moisture in the waste gas, and then the filtered waste gas is passed into the activated carbon box 14 to intercept organic matter, and the treated clean gas is discharged through the chimney;

[0048] S5, the waste liquid free of ammonia nitrogen obtained by treatment in the ammonia stripping tower in step S41 is discharged to the silver-containing concentrated water pretreatment system.

[0049] The silver-containing wastewater in step S1 includes silver-containing concentrated water and silver-containing fresh water collected in an intermediate water tank by a corresponding wastewater collection system. The silver-containing concentrated water and silver-containing fresh water in the intermediate water tank are lifted into a collection pool by pumping.

[0050] All the waste gas containing gaseous phase ammonia nitrogen stripped by the ammonia stripping tower in step S41 and the silver-containing waste gas generated by the production line collected by the gas collecting pipeline are introduced into the spray tower in step S42 for spray absorption treatment. The gas collecting pipeline is externally connected to the waste gas discharge port of the reaction kettle and the washing kettle.

[0051] In step S5, the waste liquid from which ammonia nitrogen has been removed is first discharged into a water outlet tank for temporary storage, and then the waste liquid from which ammonia nitrogen has been removed in the water outlet tank is introduced into a silver-containing concentrated water pretreatment system by pumping, mixed with the original acidic silver-containing concentrated water, and then the pH value of the mixed liquid is adjusted to 4-6 before being discharged into a sewage station for treatment.

[0052] The ammonia nitrogen concentration in the waste liquid obtained by the step S5 is less than 2300 mg / l, the steam-water ratio of the waste gas containing gaseous ammonia nitrogen in the ammonia stripping tower is 3000:1, and the air volume of the acid-alkali resistant blower is 3500m 3 / h-4500m 3 / h; the waste gas volume generated by the reactor and the washing kettle is 700m 3 / h, the air volume of the fan connected to the gas collection pipeline is 1000m 3 / h-1500m 3 / h.

[0053] The invention collects the collected silver-containing concentrated water and silver-containing fresh water, homogenizes and equalizes the amount, adds alkali to adjust the pH value to 11, heats the water to 35°C-40°C, and introduces the water into at least one primary ammonia stripping tower, strips the ammonia nitrogen in the silver-containing wastewater in the form of gas phase, and makes the ammonia nitrogen concentration of the wastewater after pretreatment less than 2300 mg / l, and then directly discharges the silver-containing wastewater with ammonia nitrogen removed into the silver-containing concentrated water pretreatment system, mixes with the original acidic silver-containing concentrated water, and adjusts the pH value to 5 before entering the sewage station for treatment, so as to effectively avoid the high ammonia nitrogen content in the concentrated wastewater and the fresh wastewater. The treatment of the silver-containing concentrated water pretreatment system can be avoided, and ammonia nitrogen pollution in the water body can be avoided; furthermore, the waste gas containing gaseous ammonia nitrogen that is blown off is uniformly passed through at least one spray tower, and the gaseous ammonia nitrogen and dilute sulfuric acid liquid are contacted and reacted to the maximum extent by spraying, thereby reducing the ammonia nitrogen concentration in the water and the exhaust gas, and then enters the demister and activated carbon adsorption box in turn to filter out excess moisture in the waste gas and intercept organic matter in the waste gas. Finally, the treated clean gas is discharged through the chimney to achieve environmental protection effects and maintain the balance of the water ecosystem.

[0054] The step S42 is implemented based on a spray tower, which includes a spray tower body 1 with an air inlet for circulating gaseous ammonia nitrogen-containing waste gas at the bottom, and upper and lower packing layers are installed at intervals in the spray tower body 1, and a spray assembly is installed above the packing layers at intervals; the spray assembly includes a grid main pipe 2 which is connected horizontally and vertically and fixedly installed in the spray tower body 1, and a plurality of spray heads 3 which can be moved up and down are installed below the grid main pipe 2, and the spray heads 3 are opened and closed alternately and adjacent spray heads are opened and closed alternately, and a corresponding push plate 8 is fixedly installed on the top outer side of the spray head 3; the packing layer is composed of a plurality of packing materials filled on an air distribution plate 5, and a plurality of air permeable holes with a pore size smaller than the particle size of the packing materials are evenly distributed on the surface of the air distribution plate 5, and the upper surface of the packing materials of the lower packing layer is stacked in a continuously staggered concave-convex shape and is fixed by a mesh cover 6 with a wavy cross-section, and the air distribution plate 5 of the upper packing layer is set to be wavy and symmetrical with the mesh cover 6.

[0055] The gaseous ammonia nitrogen of the present invention enters the spray tower to react with the dilute sulfuric acid to reduce the ammonia nitrogen concentration in the gas and liquid; two layers of packing layers and two layers of spray components are arranged in the spray tower at intervals, the upper surface of the packing material of the lower packing layer is stacked in a continuous and staggered concave-convex shape and is fixed by a mesh cover 6 with a wavy cross section, and the gas distribution plate 5 of the upper packing layer is arranged in a wavy shape symmetrical to the mesh cover 6; and the spray head 3 of the spray component is arranged in a one-to-one correspondence with the concave and convex positions of the mesh cover 6, the spray head 3 is connected to the branch pipe 7 through a bellows 4, and the electromagnetic valve is opened to Under the action of force, the spray head 3 is driven to move downward, and the push plate 8 fixed to the spray head 3 is driven to move downward to press the uploaded airflow downward, so that it is pushed and diffused laterally to the surrounding areas; the opening and closing of the spray head 3 is set to be staggered and alternately opened and closed, and the closed spray head 3 drives the push plate 8 to move upward under the action of the elastic potential energy of the elastic member 9, further pushing the gas laterally to the surrounding areas, so that the gas forms a lateral turbulence and flipping between the mesh cover 6 and the upper air distribution plate 5, and then the airflow enters the concave and convex wavy filler layer for full contact reaction, greatly increasing the contact area between the gas and the liquid, and further improving the spraying effect.

[0056] Corresponding branch pipes 7 are provided below the grid main pipe 2 at the concave and convex positions corresponding to the mesh cover 6, and the branch pipes 7 are connected to the sprinkler head 3 via corresponding bellows 4. The outer side of the bellows 4 is sleeved with elastic members 9 whose ends are respectively fixed to the push plate 8 and the branch pipe 7.

[0057] The branch pipes 7 are all equipped with corresponding controllable solenoid valves, which are used to control the opening or closing of the sprinkler head 3. That is, the controllable solenoid valve is opened and closed after a delay of T, and the closing time is T. When the controllable solenoid valve is closed, the controllable solenoid valve adjacent to it is opened and delayed for a time of T.

[0058] The spray head 3 of the present invention is connected to the branch pipe 7 through the bellows 4, thereby ensuring that it can move up and down; when the solenoid valve is opened, the impact force of the liquid spraying drives the spray head 3 and the push plate 8 to move downward, and the elastic potential energy of the stretched elastic member 9 is used to drive the closed spray head 3 to move upward and reset, so that the spray head 3 and the push plate 8 can be moved up and down without adding other power, thereby ensuring the practical effect of the present invention on the basis of controlling energy consumption.

[0059] The spray heads 3 of the spray assemblies on the upper and lower layers are opened and closed alternately. That is, when the spray head 3 of the spray assembly on the lower layer is opened, the spray head 3 of the spray assembly on the upper layer is closed, and when the spray head 3 of the spray assembly on the lower layer is closed, the spray head 3 of the spray assembly on the upper layer is opened.

[0060] The spray heads 3 of the upper and lower spray assemblies of the present invention are also opened and closed alternately. When the lower baffle plate 8 moves up, the upper baffle plate 8 moves down, thereby preventing the gas from rapidly diffusing upward, further controlling the gas to fully contact with the liquid to the maximum extent, and achieving the maximum removal of ammonia nitrogen.

[0061] The waste gas outlet of the ammonia stripping tower is connected to the air inlet of the first spray tower through the corresponding acid-base blower and the waste gas pipe. The spray towers are connected in series, and the air outlet of the front spray tower is connected to the air inlet of the rear spray tower; the first spray tower connected to the waste gas outlet of the ammonia stripping tower is connected to the exhaust port of the production line containing ammonia waste gas through the corresponding gas collecting pipeline.

[0062] 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 principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for treating high-salt, high-organic silver-containing wastewater, characterized in that: The specific steps include: S1, collecting silver-containing wastewater through a collection pool and homogenizing and averaging the amount; S2, pumping the homogenized and weighed silver-containing wastewater into a pH adjustment tank to adjust the pH value of the silver-containing wastewater to -12; S3, adding the pH-adjusted silver-containing wastewater into the intermediate water tank and heating it to 35°C-40°C; S4, removing ammonia nitrogen from the heated silver-containing wastewater, including: S41, sequentially pumping the heated silver-containing wastewater into at least one stage of ammonia stripping tower, and treating the wastewater in the ammonia stripping tower to obtain a waste gas containing gaseous ammonia nitrogen and a waste liquid free of ammonia nitrogen; S42, using an acid- and alkali-resistant blower to blow the waste gas containing gaseous ammonia nitrogen into at least one level of spray tower for spray treatment in sequence, the spray treatment comprising: passing the waste gas containing gaseous ammonia nitrogen into the spray tower for two spray treatments from bottom to top, and in the process of the waste gas containing gaseous ammonia nitrogen flowing upward, by controlling the spray heads (3) to spray in a staggered manner, the spray heads in the open state move downward under the action of the impact force of the liquid discharge, and drive the push plate (4) fixed to the outer edge of the spray head (3) to move downward to push the uploaded waste gas containing gaseous ammonia nitrogen downward, so that the gas flows in a horizontal distribution around; the spray heads (3) in the closed state reset and move upward under the action of the elastic potential energy of the elastic member (9); S43, the waste gas containing gaseous ammonia nitrogen from the previous spray tower is discharged to the next spray tower for reabsorption, and the waste gas after absorption by the last spray tower enters the demister (13) to filter out excess moisture in the waste gas, and then the filtered waste gas is passed into the activated carbon box (14) to intercept organic matter, and the treated clean gas is discharged through the chimney to meet the standards; S5, the waste liquid free of ammonia nitrogen obtained by treatment in the ammonia stripping tower in step S41 is discharged to the silver-containing concentrated water pretreatment system.

2. A method for treating high-salt, high-organic silver-containing wastewater according to claim 1, characterized in that: The silver-containing wastewater in step S1 includes silver-containing concentrated water and silver-containing fresh water collected in an intermediate water tank by a corresponding wastewater collection system. The silver-containing concentrated water and silver-containing fresh water in the intermediate water tank are lifted into a collection pool by pumping.

3. A method for treating high-salt, high-organic silver-containing wastewater according to claim 1, characterized in that: All the waste gas containing gaseous phase ammonia nitrogen stripped by the ammonia stripping tower in step S41 and the silver-containing waste gas generated by the production line collected by the gas collecting pipeline are introduced into the spray tower in step S42 for spray absorption treatment. The gas collecting pipeline is externally connected to the waste gas discharge port of the reaction kettle and the washing kettle.

4. A method for treating high-salt, high-organic silver-containing wastewater according to claim 1, characterized in that: In step S5, the waste liquid from which ammonia nitrogen has been removed is first discharged into a water outlet tank for temporary storage, and then the waste liquid from which ammonia nitrogen has been removed in the water outlet tank is introduced into a silver-containing concentrated water pretreatment system by pumping, mixed with the original acidic silver-containing concentrated water, and then the pH value of the mixed liquid is adjusted to 4-6 before being discharged into a sewage station for treatment.

5. A method for treating high-salt, high-organic silver-containing wastewater according to claim 3, characterized in that: The ammonia nitrogen concentration in the waste liquid obtained by the step S5 is less than 2300 mg / l, the steam-water ratio of the waste gas containing gaseous ammonia nitrogen in the ammonia stripping tower is 3000:1, and the air volume of the acid-alkali resistant blower is 3500m 3 / h-4500m 3 / h; the waste gas volume generated by the reactor and the washing kettle is 700m 3 / h, the air volume of the fan connected to the gas collection pipeline is 1000m 3 / h-1500m 3 / h.

6. A method for treating high-salt, high-organic silver-containing wastewater according to claim 1, characterized in that: The step S42 is implemented based on a spray tower, wherein the spray tower comprises a spray tower body (1) having an air inlet at the bottom for circulating gaseous ammonia nitrogen-containing waste gas, wherein two upper and lower packing layers are installed at intervals in the spray tower body (1), and a spray assembly is installed at intervals above the packing layers; the spray assembly comprises a grid main pipe (2) which is connected horizontally and vertically and fixedly installed in the spray tower body (1), wherein a plurality of spray heads (3) which can be moved up and down are installed at the bottom of the grid main pipe (2), and the spray heads (3) are opened and closed alternately and Adjacent spray heads are opened and closed in a staggered manner, and a corresponding push plate (4) is fixedly installed on the outer side of the top of the spray head (3); the packing layer is composed of a plurality of packing materials filled on an air distribution plate (5), and a plurality of air holes with a pore size smaller than the particle size of the packing materials are evenly distributed on the surface of the air distribution plate (5); the upper surface of the packing materials of the lower packing layer is stacked in a continuously staggered concave-convex shape and is fixed by a mesh cover (6) with a wavy cross-section; the air distribution plate (5) of the upper packing layer is set to a wavy shape that is symmetrical with the mesh cover (6) in the upper and lower directions.

7. A method for treating high-salt, high-organic silver-containing wastewater according to claim 6, characterized in that: Corresponding branch pipes (7) are provided below the main mesh pipe (2) and are connected to the concave and convex positions of the mesh cover (6), and the branch pipes (7) are connected to the sprinkler head (3) via corresponding bellows (8). The outer side of the bellows (8) is sleeved with an elastic member (9) whose ends are respectively fixed to the push plate (4) and the branch pipe (7).

8. A method for treating high-salt, high-organic silver-containing wastewater according to claim 7, characterized in that: The branch pipes (7) are each equipped with a corresponding controllable electromagnetic valve (), and the controllable electromagnetic valve () is used to control the opening or closing of the spray head (3).

9. A method for treating high-salt, high-organic silver-containing wastewater according to claim 8, characterized in that: The spray heads (3) of the spray assemblies on the upper and lower layers are opened and closed alternately.

10. A method for treating high-salt, high-organic-matter silver-containing wastewater according to claim 9, characterized in that: The waste gas outlet of the ammonia stripping tower is connected to the air inlet of the first spray tower through the corresponding acid-base blower and the waste gas pipe. The spray towers are connected in series, and the air outlet of the front spray tower is connected to the air inlet of the rear spray tower; the first spray tower connected to the waste gas outlet of the ammonia stripping tower is connected to the exhaust port of the production line containing ammonia waste gas through the corresponding gas collecting pipeline.

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