Ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system
By combining polysaccharide reaction, deammoniation, high-pressure reverse osmosis, and evaporation drying equipment to treat the mother liquor from silver powder production, the problem of treating high-concentration ammonia and formaldehyde-containing wastewater has been solved. Byproduct recovery and wastewater discharge meeting standards have been achieved, demonstrating safe and efficient treatment results.
Patent Information
- Application Number
- CN202423310727.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-31
AI Technical Summary
Existing wastewater treatment systems are ineffective at treating the high-concentration ammonia- and formaldehyde-containing mother liquor generated during silver powder production, and it is also difficult to recover valuable by-products.
A combined system consisting of a polysaccharide reaction unit, a deammoniation unit, a high-pressure reverse osmosis unit, an evaporation drying unit, and an AO biochemical unit is adopted. The polysaccharide reaction reduces the formaldehyde concentration, the deammoniation unit recovers ammonia to prepare ammonium sulfate, the high-pressure reverse osmosis reduces the volume of wastewater, the evaporation drying solidifies the wastewater, and the AO biochemical treatment achieves the required discharge standards.
It achieves safe and efficient treatment of mother liquor from silver powder production containing ammonia and formaldehyde, recovers high-purity ammonium sulfate byproduct, reduces hazardous waste, and ensures wastewater meets discharge standards, demonstrating high safety and economic efficiency.
Smart Images
Figure CN223722967U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of industrial wastewater treatment technology, specifically relating to a mother liquor treatment system for silver powder production containing ammonia and formaldehyde. Background Technology
[0002] For many years, the photovoltaic industry has been one of the world's fastest-growing and most stable sectors. In the manufacturing process of solar cells, the cell paste, as a crucial material, significantly influences the cell's conversion efficiency, solderability, tensile strength, printing performance, aging, and other electrical performance indicators. Silver powder is a primary raw material for the conductive paste in solar cells and an essential material for many modern electronic devices; currently, nearly 90% of silver powder is imported. With the rapid development of my country's electronics industry, the demand for silver powder is increasing daily, and several ultrafine silver powder production projects have been launched, accelerating the pace of import substitution.
[0003] Currently, the mainstream process for producing silver powder is the liquid-phase reduction method. One method for producing silver powder is the process of reacting formaldehyde with silver ammonia solution to produce elemental silver. The reaction principle is as follows: Silver nitrate first reacts with ammonia to produce silver hydroxide and ammonium nitrate. Silver hydroxide is unstable and will further generate silver oxide. Silver oxide reacts with ammonia to generate silver ammonia solution. Then, formaldehyde reacts with silver ammonia solution to generate silver powder for recovery.
[0004] AgNO3 + NH4OH → AgOH + NH4NO3
[0005] 2AgOH→Ag2O+H2O
[0006] Ag2O+4NH4OH→2[Ag(NH3)2]OH+3H2O
[0007] 2[Ag(NH3)2]OH+CH2O→2Ag+HC=OONH4+3NH3+H2O
[0008] The reaction mother liquor remaining after the silver powder is recovered in this silver powder production method needs to be treated to meet standards before being discharged (the emission standards typically require COD < 200 mg / L and TN < 40 mg / L). This is because the reaction mother liquor contains high concentrations of formaldehyde, formic acid, ammonia nitrogen, and nitrates, with COD approximately 30,000–40,000 mg / L and NO3... - With a concentration of approximately 15,000–20,000 mg / L and an NH3-N concentration of approximately 9,000 mg / L, the wastewater is complex and highly concentrated. Current treatment systems struggle to effectively treat this type of ammonia- and formaldehyde-containing wastewater and recover valuable byproducts. Utility Model Content
[0009] The utility model discloses a kind of silver powder production mother liquor treatment systems containing ammonia and formaldehyde, which are safe and efficient for the treatment of silver powder production wastewater containing ammonia and formaldehyde and recovery of by-products.
[0010] Specifically, the silver powder production mother liquor treatment system containing ammonia and formaldehyde includes a polysaccharide reaction device, a advanced oxidation device, a deamination device, a high-pressure reverse osmosis device, an evaporation drying device, and an AO biochemical device. The polysaccharide reaction device is provided with a dosing assembly for adding calcium hydroxide to cause polysaccharide reaction of formaldehyde in water. The deamination device is a deamination membrane device or a stripping ammonia stripping device, which is used for deamination treatment of low formaldehyde wastewater to obtain deamination product water and ammonium sulfate solution or ammonia water. The water inlet of the polysaccharide reaction device is connected to the silver powder production mother liquor, the water outlet of the polysaccharide reaction device is communicated with the water inlet of the advanced oxidation device, the water outlet of the advanced oxidation device is communicated with the water inlet of the deamination device, the deamination product water outlet of the deamination device is communicated with the water inlet of the high-pressure reverse osmosis device, the concentrated water outlet of the high-pressure reverse osmosis device is communicated with the water inlet of the evaporation drying device, and the water outlet of the high-pressure reverse osmosis device and the condensed water outlet of the evaporation drying device are communicated with the water inlet of the AO biochemical device.
[0011] In some specific embodiments, the dosing assembly includes a medicament storage tank and a medicament delivery pump, and the medicament storage tank is communicated with the medicament inlet of the polysaccharide reaction device through the medicament delivery pump.
[0012] In some specific embodiments, the polysaccharide reaction device includes a polysaccharide reaction tank and a sedimentation tank in communication. The water inlet of the polysaccharide reaction tank is connected to the silver powder production mother liquor, the supernatant water outlet of the sedimentation tank is communicated with the water inlet of the advanced oxidation device, and the sludge outlet of the sedimentation tank is communicated with the water inlet of the polysaccharide reaction tank. The polysaccharide reaction device is also provided with a heater for controlling the temperature of water in the polysaccharide reaction device.
[0013] In some specific embodiments, the advanced oxidation device is selected from at least one of an ozone oxidation device, a photocatalytic oxidation device, a Fenton oxidation device, and an electrochemical oxidation device.
[0014] In some specific embodiments, the deamination membrane device is provided with N-stage deamination membrane units, and N is 1-3. Each stage of the deamination membrane unit is provided with a water inlet and a deamination product water outlet on one side of the deamination membrane, and a sulfuric acid solution inlet and an ammonium sulfate solution outlet on the other side of the deamination membrane. The water inlet of the first-stage deamination membrane unit is communicated with the water outlet of the advanced oxidation device, the deamination product water outlets of each stage of the deamination membrane unit are communicated with the water inlets of the next-stage deamination membrane units, and the deamination product water outlet of the last-stage deamination membrane unit is communicated with the water inlet of the high-pressure reverse osmosis device.
[0015] In some specific embodiments, the deaminating membrane of the deaminating membrane device is selected from at least one of polytetrafluoroethylene membrane, polypropylene membrane, and polyvinylidene fluoride membrane.
[0016] In some specific embodiments, a reverse osmosis adjusting tank is arranged on a pipeline in communication between the deaminated water outlet of the deaminating device and the water inlet of the high-pressure reverse osmosis device, for adjusting the pH of the deaminated water to 6.5-7; the reverse osmosis adjusting tank is provided with a pH adjusting agent adding assembly I, which comprises a pH adjusting agent storage tank I and a delivery pump I, and the pH adjusting agent storage tank I is in communication with the water inlet of the reverse osmosis adjusting tank through the delivery pump I.
[0017] In some specific embodiments, the evaporation and drying device comprises an evaporation unit and a drying unit, the water inlet of the evaporation unit is in communication with the concentrated water outlet of the high-pressure reverse osmosis device, the evaporation mother liquor outlet of the evaporation unit is in communication with the water inlet of the drying unit, the evaporation condensate water outlet of the evaporation unit is in communication with the water inlet of the AO biochemical device, and the drying condensate water outlet of the drying unit is in communication with the water inlet of the AO biochemical device.
[0018] In some specific embodiments, the AO biochemical device is provided with a biochemical adjusting tank in front of it, for collecting the produced water of the high-pressure reverse osmosis device and the condensate water of the evaporation and drying device and adjusting the pH to 6.5-7; the biochemical adjusting tank is provided with a pH adjusting agent adding assembly II and a carbon source adding assembly, the pH adjusting agent adding assembly II comprises a pH adjusting agent storage tank II and a delivery pump II, and the pH adjusting agent storage tank II is in communication with the water inlet of the biochemical adjusting tank through the delivery pump II; the carbon source adding assembly comprises a carbon source storage tank and a delivery pump III, and the carbon source storage tank is in communication with the water inlet of the biochemical adjusting tank through the delivery pump III.
[0019] In some specific embodiments, the AO biochemical device comprises a primary AO biochemical unit and a secondary AO biochemical unit in sequence.
[0020] Beneficial effects: in the utility model, the formaldehyde concentration of the silver powder production mother liquor is reduced through the polysaccharide reaction device and the advanced oxidation device, which is beneficial to reducing the ammonia nitrogen concentration in water through the subsequent deamination device, and recovering ammonia in water to obtain high-purity ammonium sulfate by-products or ammonia water, then the high-pressure reverse osmosis device is used to obtain water and concentrated water rich in COD, total nitrogen and other pollutants, so that the wastewater is subjected to reduction treatment, the concentrated water obtained through the evaporation drying device is treated to obtain dried solid, and the dried solid is collected and transported to an institution with solid waste / hazardous waste disposal qualification for further treatment, and the water produced by the high-pressure reverse osmosis device and the condensed water obtained by the evaporation drying device are uniformly introduced into the AO biochemical device for treatment, so that the effluent meets the discharge standard. The key of the utility model is that a specific polysaccharide reaction device, an advanced oxidation device, a deamination device, a high-pressure reverse osmosis device, an evaporation drying device and an AO biochemical device are combined to process the ammonia-containing and formaldehyde-containing silver powder production mother liquor, so that the ammonia in the wastewater can be recovered to obtain high-purity ammonium sulfate by-products, the wastewater can meet the discharge standard, the amount of hazardous waste is reduced, and the treatment process has high safety and process economy. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 is the structure schematic diagram of the ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system provided by the utility model embodiment 1.
[0022] Figure 2 is the local structure schematic diagram of the ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system provided by the utility model embodiment 1.
[0023] Figure 3 is the water inflow and outflow amount statistics diagram of each treatment link of the ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system provided by the utility model embodiment 1. DETAILED DESCRIPTION
[0024] Referring Figure 1 , the ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system provided by the utility model comprises a polysaccharide reaction device, an advanced oxidation device, a deamination device, a high-pressure reverse osmosis device, an evaporation drying device and an AO biochemical device. The water inlet of the polysaccharide reaction device is connected with the silver powder production mother liquor, the water outlet of the polysaccharide reaction device is communicated with the water inlet of the advanced oxidation device, the water outlet of the advanced oxidation device is communicated with the water inlet of the deamination device, the deamination water outlet of the deamination device is communicated with the water inlet of the high-pressure reverse osmosis device, the concentrated water outlet of the high-pressure reverse osmosis device is communicated with the water inlet of the evaporation drying device, and the water outlet of the high-pressure reverse osmosis device and the condensed water outlet of the evaporation drying device are communicated with the water inlet of the AO biochemical device.
[0025] In the utility model, the polysaccharide reaction device is used for de-formaldehyde treatment of the silver powder production mother liquor to obtain de-formaldehyde clear liquid. The polysaccharide reaction device is provided with a dosing assembly for adding calcium hydroxide to make the formaldehyde in water undergo polysaccharide reaction.
[0026] Further, the medicine adding assembly comprises a medicine storage tank and a medicine delivery pump, the medicine storage tank is communicated with the medicine inlet of the polysaccharide reaction device through the medicine delivery pump.
[0027] Further, the polysaccharide reaction device comprises a polysaccharide reaction tank and a sedimentation tank which are communicated, the water inlet of the polysaccharide reaction tank is connected with the silver powder production mother liquor, the supernatant outlet of the sedimentation tank is connected with the water inlet of the advanced oxidation device, and the sludge outlet of the sedimentation tank is connected with the water inlet of the polysaccharide reaction tank. The specific shape and size of the polysaccharide reaction tank and the sedimentation tank can be selected and adjusted according to the actual treatment capacity of the silver powder production mother liquor, and the utility model is not particularly limited. The sedimentation tank is preferably a inclined plate sedimentation tank. The silver powder production mother liquor first enters the polysaccharide reaction tank, under the condition of calcium hydroxide and the alkalinity of the silver powder production mother liquor itself, the formaldehyde in water occurs polysaccharide reaction, so that the formaldehyde concentration is greatly reduced, then the supernatant after formaldehyde removal is further treated by the advanced oxidation device through the sludge-water separation effect of the sedimentation tank, and the separated sludge can be returned to the polysaccharide reaction tank to continue participating in the polysaccharide reaction.
[0028] Further, the polysaccharide reaction device is provided with a heater for controlling the temperature of water in the polysaccharide reaction device, so as to better promote the formaldehyde in water to occur polysaccharide reaction to reduce the formaldehyde concentration.
[0029] In the utility model, the advanced oxidation device is used for oxidizing treatment of the formaldehyde-removed clear liquid, further reduces the formaldehyde concentration in water, and low formaldehyde wastewater is obtained. The advanced oxidation device is preferably at least one of an ozone oxidation device, a photocatalytic oxidation device, a Fenton oxidation device and an electrochemical oxidation device, and more preferably is an ozone oxidation device. The specific structure and size of the advanced oxidation device can be selected and adjusted according to the actual treatment capacity of the silver powder production mother liquor and the existing device structure, and the utility model is not particularly limited.
[0030] In the utility model, the deamination device is a deamination membrane device or a steam stripping ammonia device, which is used for deamination treatment of the low formaldehyde wastewater to obtain deamination product water and ammonium sulfate solution or ammonia water. The deamination membrane device uses sulfuric acid solution as the absorption liquid to obtain ammonium sulfate solution and deamination product water. The steam stripping ammonia device is used for treating the steam to obtain free ammonia and deamination wastewater, and the free ammonia is mixed with water to obtain ammonia water.
[0031] Further, the deamination membrane device is provided with N-stage deamination membrane units, and N is 1-3, that is, the deamination membrane device can only comprise a first-stage deamination membrane unit, can comprise a first-stage deamination membrane unit and a second-stage deamination membrane unit, or can comprise a first-stage deamination membrane unit, a second-stage deamination membrane unit and a third-stage deamination membrane unit. The utility model is preferably provided with a first-stage deamination membrane unit, a second-stage deamination membrane unit and a third-stage deamination membrane unit, so as to improve the deamination treatment efficiency and further reduce the ammonia nitrogen concentration in water.
[0032] Further, each stage of the deamination membrane unit is provided with a water inlet and a deamination product water outlet on one side of the deamination membrane, and a sulfuric acid solution inlet and an ammonium sulfate solution outlet on the other side of the deamination membrane.
[0033] Further, the water inlet of the primary deamination membrane unit is in communication with the water outlet of the advanced oxidation device, the deamination product water outlet of each stage of the deamination membrane unit is in communication with the water inlet of the next stage of the deamination membrane unit, and the deamination product water outlet of the last stage of the deamination membrane unit is in communication with the water inlet of the high-pressure reverse osmosis device.
[0034] Further, the deamination membrane of the deamination membrane device is preferably at least one of a polytetrafluoroethylene membrane, a polypropylene membrane, and a polyvinylidene fluoride membrane. The operating pressure of the deamination membrane device is preferably 0.2-0.6 bar, such as 0.2 bar, 0.3 bar, 0.4 bar, 0.5 bar, 0.6 bar, or any value therebetween.
[0035] Further, the steam stripping ammonia device is provided with a steam inlet, an ammonia gas outlet, a water inlet, and a deamination product water outlet. The water inlet of the steam stripping ammonia device is in communication with the water outlet of the advanced oxidation device, and the deamination product water outlet of the steam stripping ammonia device is in communication with the water inlet of the high-pressure reverse osmosis device. The ammonia gas outlet is mixed with water to obtain ammonia water.
[0036] In the utility model, the high-pressure reverse osmosis device is used for reducing the amount of deamination product water, obtaining concentrated water rich in pollutants such as COD and total nitrogen, and product water containing a small amount of small molecular pollutants such as formic acid and formaldehyde.
[0037] Further, a reverse osmosis conditioning tank is provided on the pipeline in communication between the deamination product water outlet of the deamination device and the water inlet of the high-pressure reverse osmosis device, for adjusting the pH of the deamination product water to 6.5-7, which is more conducive to improving the retention effect of reverse osmosis and prolonging the service life of the reverse osmosis membrane.
[0038] Further, the reverse osmosis conditioning tank is provided with a pH regulator adding assembly I, which includes a pH regulator storage tank I and a delivery pump I. The pH regulator storage tank I is in communication with the water inlet of the reverse osmosis conditioning tank through the delivery pump I. The number of pH regulator storage tanks I and delivery pumps I can be set according to actual needs.
[0039] In the utility model, the evaporation drying device is used for evaporative drying treatment of the concentrated water obtained by the high-pressure reverse osmosis device, obtaining condensed water and dried solids, thereby realizing further reduction of wastewater, and reducing the amount of hazardous waste.
[0040] Further, the evaporation and drying device comprises an evaporation unit and a drying unit, a water inlet of the evaporation unit is communicated with a concentrated water outlet of the high-pressure reverse osmosis device, an evaporation mother liquor outlet of the evaporation unit is communicated with a water inlet of the drying unit, an evaporation condensate water outlet of the evaporation unit is communicated with a water inlet of the AO biochemical device, and a drying condensate water outlet of the drying unit is communicated with a water inlet of the AO biochemical device. The evaporation unit can be selected from various existing evaporation devices, and is preferably a single-effect MVR evaporation device. The drying unit can be selected from various existing drying devices, and is preferably a scraper drying device. The concentrated water obtained by the high-pressure reverse osmosis device is first introduced into the evaporation unit for treatment to obtain evaporation mother liquor and evaporation condensate water, the evaporation mother liquor is introduced into the drying unit for further treatment to obtain drying condensate water and drying solid, the drying solid is collected and transported to an institution with solid waste / hazardous waste disposal qualification for further treatment, and the evaporation condensate water and the drying condensate water are introduced into the subsequent AO biochemical device for treatment.
[0041] In the utility model, the AO biochemical device is used for biochemical treatment of the water produced by the high-pressure reverse osmosis device and the condensate water of the evaporation and drying device to obtain qualified drainage. The condensate water comprises evaporation condensate water and drying condensate water.
[0042] Further, the AO biochemical device is provided with a biochemical adjustment tank in advance, which is used for collecting the water produced by the high-pressure reverse osmosis device and the condensate water of the evaporation and drying device and adjusting the pH to 6.5-7, so that the biochemical treatment effect is improved.
[0043] Further, the biochemical adjustment tank is provided with a pH adjusting agent adding assembly II and a carbon source adding assembly. The pH adjusting agent adding assembly II comprises a pH adjusting agent storage tank II and a delivery pump II, and the pH adjusting agent storage tank II is communicated with the water inlet of the biochemical adjustment tank through the delivery pump II. The number of the pH adjusting agent storage tank II and the delivery pump II can be set according to actual needs.
[0044] Further, the carbon source adding assembly comprises a carbon source storage tank and a delivery pump III, and the carbon source storage tank is communicated with the water inlet of the biochemical adjustment tank through the delivery pump III. The number of the carbon source storage tank and the delivery pump III can be set according to actual needs.
[0045] Further, the AO biochemical device comprises a primary AO biochemical unit and a secondary AO biochemical unit which are communicated in sequence, so that the biochemical treatment effect is improved, and the effluent is qualified.
[0046] The utility model will be described in detail through specific embodiments.
[0047] Embodiment 1
[0048] This embodiment is used to illustrate a silver powder production mother liquor treatment system containing ammonia and formaldehyde, which refers to Figure 1The system specifically comprises: a polysaccharide reaction device 1, a high-level oxidation device 2, a deamination membrane device 3, a high-pressure reverse osmosis device 4, an evaporation drying device 5, and an AO biochemical device 6.
[0049] The polysaccharide reaction device 1 is provided with a medicament adding assembly, which comprises a medicament storage tank (containing calcium hydroxide solution) and a medicament delivery pump, and the medicament storage tank is communicated with the medicament inlet of the polysaccharide reaction device 1 through the medicament delivery pump. The polysaccharide reaction device 1 comprises a polysaccharide reaction tank and an inclined plate sedimentation tank which are communicated, the water inlet of the polysaccharide reaction tank is connected to the silver powder production mother liquor, the supernatant outlet of the inclined plate sedimentation tank is communicated with the water inlet of the high-level oxidation device 2, and the sludge outlet of the inclined plate sedimentation tank is communicated with the water inlet of the polysaccharide reaction tank. The polysaccharide reaction device is also provided with a heater for controlling the temperature of water in the polysaccharide reaction device.
[0050] The high-level oxidation device 2 comprises a reaction tank and an ozone generator.
[0051] Referring to Figure 2 , the deamination membrane device 3 comprises a first-stage deamination membrane unit 31, a second-stage deamination membrane unit 32 and a third-stage deamination membrane unit 33 which are communicated in sequence, each deamination membrane unit is provided with a water inlet and a deamination product water outlet on one side of the deamination membrane, and a sulfuric acid solution inlet and an ammonium sulfate solution outlet on the other side of the deamination membrane. The water inlet of the first-stage deamination membrane unit 31 is communicated with the water outlet of the high-level oxidation device 2, the deamination product water outlet of the first-stage deamination membrane unit 31 is communicated with the water inlet of the second-stage deamination membrane unit 32, the deamination product water outlet of the second-stage deamination membrane unit 32 is communicated with the water inlet of the third-stage deamination membrane unit 33, and the deamination product water outlet of the third-stage deamination membrane unit 33 is communicated with the water inlet of the high-pressure reverse osmosis device 4. The deamination membranes of the first-stage deamination membrane unit 31, the second-stage deamination membrane unit 32 and the third-stage deamination membrane unit 33 are all polytetrafluoroethylene membranes.
[0052] The deamination product water outlet of the third-stage deamination membrane unit 33 and the water inlet of the high-pressure reverse osmosis device 4 are communicated through a pipeline, and a reverse osmosis adjusting tank is arranged on the pipeline, the reverse osmosis adjusting tank is provided with a pH adjusting agent adding assembly I, and the pH adjusting agent adding assembly I comprises a pH adjusting agent storage tank I and a delivery pump I, and the pH adjusting agent storage tank I is communicated with the water inlet of the reverse osmosis adjusting tank through the delivery pump I.
[0053] The high-pressure reverse osmosis device 4 adopts a single-stage DTRO membrane assembly, the concentrated water outlet of the high-pressure reverse osmosis device 4 is communicated with the water inlet of the evaporation drying device 5, and the product water outlet of the high-pressure reverse osmosis device 4 is communicated with the water inlet of the AO biochemical device 6.
[0054] The evaporation and drying device 5 comprises a single-effect MVR evaporation device and a scraper drying device. The water inlet of the single-effect MVR evaporation device is communicated with the concentrated water outlet of the high-pressure reverse osmosis device 4. The evaporation mother liquor outlet of the single-effect MVR evaporation device is communicated with the water inlet of the scraper drying device. The evaporation condensate water outlet of the single-effect MVR evaporation device is communicated with the water inlet of the biochemical conditioning tank. The drying condensate water outlet of the scraper drying device is communicated with the water inlet of the biochemical conditioning tank.
[0055] The AO biochemical device 6 is provided with a biochemical conditioning tank in advance, which is used for collecting the product water of the high-pressure reverse osmosis device and the condensate water of the evaporation and drying device and adjusting the pH. The biochemical conditioning tank is provided with a pH regulator adding assembly II and a carbon source adding assembly. The pH regulator adding assembly II comprises a pH regulator storage tank II and a delivery pump II. The pH regulator storage tank II is communicated with the water inlet of the biochemical conditioning tank through the delivery pump II.
[0056] The AO biochemical device 6 comprises a primary AO biochemical unit and a secondary AO biochemical unit which are communicated in sequence. The water inlet of the primary AO biochemical unit is communicated with the water outlet of the biochemical conditioning tank. The primary AO biochemical unit comprises a primary A tank and a primary O tank which are communicated in sequence. The secondary AO biochemical unit comprises a secondary A tank and a secondary O tank which are communicated in sequence.
[0057] The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system provided in the embodiment is used to treat 250 t / d of silver powder mother liquor (the water quality of the inlet is shown in Table 1), and the inlet and outlet water quantity statistics diagrams of each treatment link are shown in Figure 3 An ammonium sulfate solution with a mass concentration of about 10% and a purity of 98% is obtained, 15 t / d of dried solid (with a water content of 15%) is produced, and the COD concentration of the outlet water is about 100 mg / L and the total nitrogen concentration is about 30 mg / L, which can be discharged up to the standard.
[0058] Table 1
[0059] Formaldehyde / % Ammonium formate / % Sodium nitrate / % Ammonium nitrate / % Ammonia / % pH Silver powder production mother liquor 1.5 0.7 0.5 1.3 0.7 11
[0060] Embodiment 2
[0061] The embodiment is used to illustrate an ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system, which specifically comprises a polysaccharide reaction device 1, a high-level oxidation device 2, a stripping ammonia evaporation device 3, a high-pressure reverse osmosis device 4, an evaporation and drying device 5, and an AO biochemical device 6. The structures of the devices and the connection modes are the same as those of the embodiment 1. The stripping ammonia evaporation device 3 is provided with a steam inlet, an ammonia gas outlet, a water inlet, and a deamination product water outlet. The water inlet of the stripping ammonia evaporation device is communicated with the water outlet of the high-level oxidation device 2. The deamination product water outlet of the stripping ammonia evaporation device 3 is communicated with the water inlet of the high-pressure reverse osmosis device 3. The ammonia gas outlet is mixed with water to obtain ammonia water.
[0062] The silver powder mother liquor treatment system provided by the embodiment is used to treat 250 t / d of silver powder mother liquor (the water quality of which is shown in Table 1), and about 20% ammonia water with a purity of ≥98% can be obtained, 15 t / d of dried solid (with a water content of 15%) is generated, the COD concentration of the effluent is about 100 mg / L, the total nitrogen concentration is about 30 mg / L, and the effluent can be discharged up to the standard.
[0063] Although the embodiments of the utility model have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the utility model, and the ordinary skilled in the art can change, modify, replace and transform the above-mentioned embodiments within the scope of the utility model without departing from the principles and purposes of the utility model.
Claims
1. A system for treating a mother liquor for producing ammonia-containing and formaldehyde-containing silver powder, characterized by comprising: The device comprises a polysaccharide reaction device, an advanced oxidation device, a deamination device, a high-pressure reverse osmosis device, an evaporation drying device, and an AO biochemical device. The polysaccharide reaction device is provided with a dosing assembly for adding calcium hydroxide to cause polysaccharide reaction of formaldehyde in water; the deamination device is a deamination membrane device or a stripping ammonia stripping device, which is used for deamination treatment of low formaldehyde wastewater to obtain deamination product water and ammonium sulfate solution or ammonia water; the water inlet of the polysaccharide reaction device is connected to the silver powder production mother liquor, the water outlet of the polysaccharide reaction device is communicated with the water inlet of the advanced oxidation device, the water outlet of the advanced oxidation device is communicated with the water inlet of the deamination device, the deamination product water outlet of the deamination device is communicated with the water inlet of the high-pressure reverse osmosis device, the concentrated water outlet of the high-pressure reverse osmosis device is communicated with the water inlet of the evaporation drying device, and the water outlet of the high-pressure reverse osmosis device and the condensate water outlet of the evaporation drying device are communicated with the water inlet of the AO biochemical device. The dosing assembly comprises a medicament storage tank and a medicament delivery pump, and the medicament storage tank is communicated with the medicament inlet of the polysaccharide reaction device through the medicament delivery pump.
2. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The polysaccharide reaction device comprises a polysaccharide reaction tank and a sedimentation tank in communication, the water inlet of the polysaccharide reaction tank is connected to the silver powder production mother liquor, the supernatant water outlet of the sedimentation tank is communicated with the water inlet of the advanced oxidation device, and the sludge outlet of the sedimentation tank is communicated with the water inlet of the polysaccharide reaction tank.
3. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The polysaccharide reaction device is further provided with a heater for controlling the temperature of water in the polysaccharide reaction device. The advanced oxidation device is selected from at least one of an ozone oxidation device, a photocatalytic oxidation device, a Fenton oxidation device, and an electrochemical oxidation device.
4. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The deamination membrane device is provided with N-stage deamination membrane units, and N is 1-3.
5. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, Each stage of the deamination membrane unit is provided with a water inlet and a deamination product water outlet on one side of the deamination membrane, and a sulfuric acid solution inlet and an ammonium sulfate solution outlet on the other side of the deamination membrane. The water inlet of the first-stage deamination membrane unit is communicated with the water outlet of the advanced oxidation device, the deamination product water outlets of the deamination membrane units are communicated with the water inlets of the next-stage deamination membrane units, and the deamination product water outlet of the last-stage deamination membrane unit is communicated with the water inlet of the high-pressure reverse osmosis device. The deamination membrane of the deamination membrane device is selected from at least one of a polytetrafluoroethylene membrane, a polypropylene membrane, and a polyvinylidene fluoride membrane.
6. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, A reverse osmosis adjusting tank is arranged on the pipeline in communication between the deamination product water outlet of the deamination device and the water inlet of the high-pressure reverse osmosis device, for adjusting the pH of the deamination product water to 6.5-7.
7. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The reverse osmosis adjusting tank is provided with a pH regulator dosing assembly I, and the pH regulator dosing assembly I comprises a pH regulator storage tank I and a delivery pump I, and the pH regulator storage tank I is communicated with the water inlet of the reverse osmosis adjusting tank through the delivery pump I. 8. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The evaporation and drying device comprises an evaporation unit and a drying unit, a water inlet of the evaporation unit is communicated with a concentrated water outlet of the high-pressure reverse osmosis device, an evaporation mother liquor outlet of the evaporation unit is communicated with a water inlet of the drying unit, an evaporation condensate water outlet of the evaporation unit is communicated with a water inlet of the AO biochemical device, and a drying condensate water outlet of the drying unit is communicated with a water inlet of the AO biochemical device.
9. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The AO biochemical device is provided with a biochemical adjusting tank in advance, which is used for collecting water produced by the high-pressure reverse osmosis device and condensate water of the evaporation and drying device and adjusting pH to 6.5-7; The biochemical adjusting tank is provided with a pH adjusting agent adding assembly II and a carbon source adding assembly, the pH adjusting agent adding assembly II comprises a pH adjusting agent storage tank II and a conveying pump II, and the pH adjusting agent storage tank II is communicated with a water inlet of the biochemical adjusting tank through the conveying pump II; The carbon source adding assembly comprises a carbon source storage tank and a conveying pump III, and the carbon source storage tank is communicated with the water inlet of the biochemical adjusting tank through the conveying pump III.
10. The ammonia-containing and formaldehyde-containing silver powder production mother liquor treatment system according to claim 1, characterized by, The AO biochemical device comprises a primary AO biochemical unit and a secondary AO biochemical unit which are communicated in sequence.