CN115465991B - Ferric phosphate mother liquor wastewater treatment method and system - Google Patents
Ferric phosphate mother liquor wastewater treatment method and system Download PDFInfo
- Publication number
- CN115465991B CN115465991B CN202211082185.6A CN202211082185A CN115465991B CN 115465991 B CN115465991 B CN 115465991B CN 202211082185 A CN202211082185 A CN 202211082185A CN 115465991 B CN115465991 B CN 115465991B
- Authority
- CN
- China
- Prior art keywords
- water
- mother liquor
- reverse osmosis
- tank
- osmosis membrane
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/008—Control or steering systems not provided for elsewhere in subclass C02F
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
- C02F1/048—Purification of waste water by evaporation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/441—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by reverse osmosis
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/105—Phosphorus compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/20—Heavy metals or heavy metal compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/06—Controlling or monitoring parameters in water treatment pH
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/44—Time
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
- Y02A40/10—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
- Y02A40/20—Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The invention relates to a ferric phosphate mother liquor wastewater treatment method and a system, wherein two mother liquor water flows are respectively introduced into two water collecting tanks, and mother liquor water with different water qualities is mixed, so that the content ratio of polyvalent metal ions and phosphorus in the mother liquor water is controlled to be Mg:P=1:2.6-3, mn:P=1:2-2.2, fe:P=1:1.1, and the content of water quality phosphorus is the sum of the ion ratios; at the moment, the polyvalent metal ions in the mixed mother liquor wastewater are removed by chemical precipitation, and the generated precipitate can be used as slow release fertilizer and phosphorus resource for recycling after dehydration. According to the invention, mother liquor wastewater is separately collected according to water quality, the flow is respectively controlled, and the content ratio of metal ions to phosphorus in the mixed sedimentation tank is adjusted, so that the effect of precipitating metal ions in the pretreatment process is better, the scaling of pipelines and water pump impellers and the fouling situation of a reverse osmosis membrane device are reduced or avoided, the occupied area of a water tank is reduced, and the phosphorus resource is fully utilized.
Description
Technical Field
The invention belongs to the technical field of industrial wastewater treatment, and relates to a method and a system for treating ferric phosphate mother liquor wastewater.
Background
The iron phosphate mother liquor wastewater is residual high-salt wastewater after separation and precipitation in the iron phosphate synthesis process, and the mother liquor wastewater has two strands with different water qualities, and comprises a saturated solution separated after synthesis of raw materials in a synthesis mother liquor, namely an iron phosphate production process, and an aging mother liquor, namely a saturated solution separated after constant-temperature aging process of the synthesized heterogeneous iron phosphate.
At present, the treatment method of the ferric phosphate mother liquor wastewater is divided into a lime precipitation method, a magnesium salt treatment method and a membrane treatment method: (1) Lime precipitation, which is to add a large amount of lime into the wastewater, directly discharge the supernatant without considering the total salt exceeding standard, generate a large amount of sludge which is difficult to treat, and not consider the discharge and treatment of salt; (2) Blowing off high-concentration ammonia nitrogen and precipitating magnesium ammonium phosphate, namely adding magnesium oxide and magnesium hydroxide into the wastewater to generate magnesium ammonium phosphate (struvite); the residual ammonia gas is stripped and absorbed by sulfuric acid to generate ammonium sulfate, but the method has high treatment cost, the waste water is difficult to discharge up to the standard, a subsequent membrane treatment system with excessive magnesium content is difficult to treat, and a system pipeline is easy to scale; (3) The membrane treatment method, namely, the pretreatment of the mother liquor converts most of polyvalent metal ions and phosphorus in the mother liquor into sediment, and carries out solid-liquid separation on the generated solid-liquid mixture, and the clear mother liquor is output; the clear mother liquor separation is used for removing most of particles and multivalent metal ions in the clear mother liquor and outputting low-salt mother liquor; and then water is produced through a two-stage membrane concentration output terminal.
The traditional mother liquor pretreatment method is that two strands of wastewater of the mother liquor are directly introduced into an adjusting tank, so that most of polyvalent metal ions and phosphorus in the mother liquor are converted into sediment and solid-liquid separation is carried out on a generated solid-liquid mixture, as the quality and the quantity of water of synthetic mother liquor and aged mother liquor produced in the production process of anhydrous ferric phosphate are different, the area of the adjusting tank needs to be greatly provided with a function of homogenizing water bodies, the volume of the adjusting tank is small, the mixed mother liquor is poor in treatment effect, metal ions are difficult to sediment, and when the water quality of a workshop is changed, the influence on a water treatment system is easy to cause difficult recovery, such as: the scale of the lifting pump and the pipeline is formed, and the membrane system causes serious pollution and blockage.
In patent No. 202111617465.8, a method for treating iron phosphate wastewater and a system thereof are disclosed, the method comprises the following steps: s1, preprocessing ferric phosphate mother liquor to obtain mother liquor clear filtrate, and preprocessing ferric phosphate washing water to obtain concentrated water A; s2, mixing the mother liquor clarified filtrate with the concentrated water A, and evaporating and concentrating to obtain concentrated water B; s3, cooling and crystallizing the concentrated water B by centrifugation to obtain a solid product and drying the solid product. The processing system comprises: the first pretreatment device is used for pretreating the ferric phosphate mother solution and obtaining mother solution clear filtrate; the second pretreatment device is used for pretreating the ferric phosphate washing water and obtaining concentrated water A; the evaporation concentration device is respectively communicated with the first pretreatment device and the second pretreatment device and is used for evaporating and concentrating the mother liquor clarified filtrate and the concentrated water A to obtain concentrated water B; the centrifugal device is communicated with the evaporation concentration device and is used for centrifuging the concentrated water B; the cooling crystallization device is communicated with the centrifugal device and is used for cooling and crystallizing the centrifuged product; and the drying device is respectively communicated with the centrifugal device and the cooling crystallization device and is used for drying the product after centrifugation and cooling crystallization. According to the technical scheme, the concentrated water after evaporation and concentration is subjected to operations such as centrifugation, cooling crystallization, drying and the like, so that ammonium sulfate, ammonium hydrogen phosphate, magnesium sulfate and pure water in the wastewater are recycled, and the purposes of resource recovery and zero emission are achieved. In the technical scheme, the ferric phosphate production mother liquor is divided into a synthesis mother liquor and an aging mother liquor, wherein the magnesium ion content in the synthesis mother liquor is 300-800ppm, the iron ion content is about 100ppm, the manganese ion content is about 100-150ppm, and the phosphorus content is 100ppm; the content of the impurity ions in the aging mother liquor is less, the phosphorus content is about 1500-2000ppm, two kinds of mother liquor are directly mixed for pretreatment in the 202111617465.8 patent, and because the water quality and the water quantity of the two kinds of mother liquor are different, the pretreatment precipitation multivalent metal ions mainly depend on the condition of insufficient phosphorus source in the water body at different time intervals, so that the magnesium content and the manganese content in the whole system are high, the scaling of a pipeline and a water pump impeller is difficult to clean, the reverse osmosis membrane is oxidized, the system processing capacity is reduced, the operation maintenance labor and the material cost are increased, and the reverse osmosis membrane is irreversibly damaged due to the excessive manganese ions.
In patent No. 202210433515.5, a comprehensive treatment method of wastewater generated in the production of iron phosphate is disclosed, the comprehensive treatment method comprising the steps of: (S1) washing water treatment: (S2) treatment of mother liquor: A. removing fluorine; B. dephosphorization; C. removing manganese; D. producing byproduct calcium sulfate; E. removing calcium and magnesium; F. removing ammonia; G. and (5) circulating. According to the technical scheme, zero emission of the iron phosphate wastewater is realized through process optimization, and the resources are recovered to the maximum extent by grading separation and recovery according to different properties of various impurities; the fluoride ions in the wastewater are removed in the early stage, so that high-quality ferric phosphate byproducts can be obtained, manganese dioxide and calcium sulfate are also respectively obtained in the follow-up stage, new impurities are not introduced while resources are recycled, and the wastewater comprehensive treatment method has economic value through cost benefit accounting and is slightly surplus. In the technical scheme, the pH value is regulated by utilizing calcium hydroxide in the stage D, the pH value is required to be regulated to 11-12, the ferric phosphate wastewater belongs to high ammonia nitrogen wastewater, ammonia water is adopted to regulate the pH value in the stage A and the stage B to introduce ammonium ions, when the pH value is regulated to 11-12, ammonium ions are converted into ammonia gas in high-alkalinity water quality, the ammonia gas is easy to diffuse, the ammonia concentration in the air in the stage D is high at the moment, potential safety hazards of personnel exist, and when the product calcium sulfate sludge filters a solid phase, the ammonia gas volatilizes during drying and dehydration, the operation procedure cannot avoid manual operation, and the risk of ammonia poisoning exists; meanwhile, the mother liquor pretreatment process flow is long, the content of multivalent metal ions in water is limited, and at the moment, the pretreatment agent and the operation energy consumption are high, and the labor cost is high.
In view of this, how to more optimally treat the iron phosphate mother liquor wastewater is a direction of development.
Disclosure of Invention
The invention aims to solve the technical problems, and provides the ferric phosphate mother liquor wastewater treatment method and the ferric phosphate mother liquor wastewater treatment system, which have good pretreatment effect, can ensure that a wastewater treatment system is not influenced even if the water quality of a workshop is changed, and can furthest avoid the scaling of pipelines and water pump impellers and the fouling and blocking of a membrane system during the operation and maintenance of the wastewater treatment system.
The invention is realized by the following technical scheme:
according to the iron phosphate mother liquor wastewater treatment method, two strands of mother liquor are respectively introduced into two water collecting tanks, the water yield of the two water collecting tanks is controlled, and the mother liquor water with different water qualities is mixed, so that the content ratio of multivalent metal ions to phosphorus in the mother liquor water is controlled at Mg:P=1: 2.6-3, mn: P=1:2-2.2, fe: P=1:1.1, the content of phosphorus in water is the sum of the ion proportion, at the moment, the multivalent metal ions in the mixed mother liquor wastewater are removed by chemical precipitation, the multivalent metal ions are reduced to below 5ppm, and the produced precipitate is dehydrated and then is used as slow-release fertilizer and phosphorus resource for recycling, and the produced water is reused.
The ferric phosphate mother liquor wastewater treatment method specifically comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop according to different water qualities;
and a second step of: introducing two mother liquor water flows into a primary mixing reaction tank, controlling the flow rates of the two mother liquor water flows in the primary mixing reaction tank, controlling the ratio of metal ion content to phosphorus content in the primary mixing reaction tank to be Mg:P=1:2.6-3, mn:P=1:2-2.2, fe:P=1:1.1, controlling the water quality phosphorus content to be the sum of the ion ratios, adding ammonia water, controlling the pH value of effluent to be 5.0-6.0, controlling the hydraulic retention time to be 30-60 min, and removing multivalent metal ions in the water by chemical precipitation;
and a third step of: performing mud-water separation on mud-water mixed liquid in the primary mixing reaction tank, squeezing a plate frame, and dehydrating and drying the generated sludge to be recycled as slow-release phosphate fertilizer;
fourth step: the filtered clear liquid in the third step is lifted to a secondary mixing reaction tank, ammonia water is added, the pH value is controlled to be 8.5-9.0, the hydraulic retention time is 15-30 min, and the rest metal ions are removed;
fifth step: carrying out mud-water separation on mud-water mixed liquid in the secondary mixing reaction tank, squeezing a plate frame, dehydrating and drying the generated sludge, wherein the components mainly comprise magnesium ammonium phosphate, and recycling the magnesium ammonium phosphate as slow release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: the water in a water tank in the mother liquor enters a tubular micro-filtration cycle, the produced water enters the next step, and the concentrated water continues the tubular micro-filtration cycle;
seventh step: the produced water in the sixth step is concentrated by a reverse osmosis membrane, and the produced water is used as reuse water;
eighth step: and seventh, evaporating and concentrating MVR, and centrifugally separating salt from the concentrated crystal mixed solution when the density reaches 1.38-1.42 g/cm, wherein the salt product is ammonium sulfate.
The ferric phosphate mother liquor wastewater treatment method comprises the following steps: in the sixth step, concentrated water circulates through pipe type micro-filtration, after ammonia addition and precipitation, mud-water mixture is subjected to mud-water separation plate frame squeezing, and filtered liquid returns to pipe type micro-filtration circulation.
The ferric phosphate mother liquor wastewater treatment system comprises a mother liquor collecting tank, a primary pretreatment system, a secondary pretreatment system, a mother liquor middle water tank, a tubular microfiltration system, a reverse osmosis membrane device, an MVR evaporation device, a centrifuge and a paddle dryer; the mother liquor collecting tank comprises a synthetic mother liquor collecting tank and an aging mother liquor collecting tank; the primary pretreatment system comprises a primary mixing reaction tank, a primary diaphragm plate-and-frame filter press and a primary filtrate collecting tank; the primary mixing reaction tank is used for mixing the synthesis mother liquor and the aging mother liquor and comprises a water inlet pipeline and a water outlet pipeline; the water inlet pipeline comprises a main pipeline, and a first branch and a second branch which are respectively connected with the synthetic mother liquor collecting tank and the aging mother liquor collecting tank; the inlet of the primary diaphragm plate-and-frame filter press is connected with the water outlet pipeline of the primary mixing reaction tank, and the outlet end of the primary diaphragm plate-and-frame filter press is provided with a sludge conveying pipeline and a filtered clear liquid water outlet pipeline; the first-stage filtrate collecting tank is used for collecting filtered clear liquid of the first-stage diaphragm plate-and-frame filter press, and the inlet is connected with a filtered clear liquid outlet pipeline of the first-stage diaphragm plate-and-frame filter press; the secondary pretreatment system comprises a secondary mixing reaction tank and a secondary diaphragm plate-and-frame filter press; the secondary mixing reaction tank is used for removing metal ions, and the water inlet pipeline is connected with the outlet of the primary filtrate collecting tank; the inlet of the secondary diaphragm plate-and-frame filter press is connected with the water outlet pipeline of the secondary mixing reaction tank, and the outlet end of the secondary diaphragm plate-and-frame filter press is provided with a sludge conveying pipeline and a filtered clear liquid water outlet pipeline; the mother liquor water tank is used for collecting filtered clear liquid of the secondary diaphragm plate-and-frame filter press, and the inlet is connected with a filtered clear liquid outlet pipeline of the secondary diaphragm plate-and-frame filter press; the tubular micro-filtration system is used for micro-filtration of water in the mother liquor; the reverse osmosis membrane device is used for concentrating pipe type micro-filtration produced water and is connected with the pipe type micro-filtration system; the inlet of the MVR evaporation device is connected with the concentrated water outlet of the ultra-high pressure reverse osmosis membrane group of the reverse osmosis membrane device; the centrifugal machine is used for centrifugally separating salt from the crystallized mixed solution after being concentrated by the MVR evaporation device; and the inlet of the paddle dryer is respectively connected with sludge conveying pipelines of the first-stage diaphragm plate-and-frame filter press and the second-stage diaphragm plate-and-frame filter press.
The ferric phosphate mother liquor wastewater treatment system comprises: and the first branch and the second branch are respectively provided with an electric flow regulating valve for regulating the flow of two mother liquor water flows.
The ferric phosphate mother liquor wastewater treatment system comprises: a pipeline mixer and an ammonia adding device are arranged on the primary mixing reaction tank main pipeline; and a stirring device and an acid-resistant and corrosion-resistant pump are arranged in the primary mixing reaction tank.
The ferric phosphate mother liquor wastewater treatment system comprises: the secondary mixing reaction tank is internally provided with a stirring device, the bottom of the secondary mixing reaction tank is provided with an acid-resistant and corrosion-resistant pump, and a pipeline mixer and an ammonia adding device are arranged on a water inlet pipeline.
The ferric phosphate mother liquor wastewater treatment system comprises: the tubular microfiltration system comprises a feeding reaction tank, a water supply pump, a tubular microfiltration concentrated solution tank, a circulating pump, a tubular microfiltration membrane and a tubular microfiltration water producing pool which are connected in sequence; the water outlet end of the tubular microfiltration concentrated solution tank is respectively connected with inlets of the feeding reaction tank, the circulating pump and the secondary diaphragm plate-and-frame filter press; the water outlet end of the tubular microfiltration membrane is respectively connected with the tubular microfiltration water producing pool and the tubular microfiltration concentrate tank.
The ferric phosphate mother liquor wastewater treatment system comprises: the reverse osmosis membrane device comprises a high-pressure reverse osmosis membrane group, a high-pressure reverse osmosis water producing pool, a high-pressure reverse osmosis concentrated water pool, an ultrahigh-pressure reverse osmosis membrane group and a terminal reverse osmosis membrane group; the inlet end of the high-pressure reverse osmosis membrane group is connected with the tubular micro-filtration water producing pool, and a lifting pump, a high-pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the tubular micro-filtration water producing pool to the high-pressure reverse osmosis membrane group; the inlet of the high-pressure reverse osmosis water producing pool is connected with the water producing outlet of the high-pressure reverse osmosis membrane group; the inlet of the high-pressure reverse osmosis concentrated water tank is respectively connected with the concentrated water outlets of the high-pressure reverse osmosis membrane group and the terminal reverse osmosis membrane group; the inlet of the ultra-high pressure reverse osmosis membrane group is connected with the high pressure reverse osmosis concentrated water tank, and a lifting pump, a high pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the high pressure reverse osmosis concentrated water tank to the ultra-high pressure reverse osmosis membrane group; the water outlet of the ultrahigh pressure reverse osmosis membrane group is connected with the tubular microfiltration water producing pool, and the concentrated water outlet is connected with the MVR evaporation device; the inlet of the terminal reverse osmosis membrane group is connected with the high-pressure reverse osmosis water producing tank, and a lifting pump, a high-pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the high-pressure reverse osmosis water producing tank to the terminal reverse osmosis membrane group; and the produced water of the terminal reverse osmosis membrane group is recycled, and the concentrated water outlet is connected with the inlet of the high-pressure reverse osmosis concentrated water tank.
The beneficial effects are that:
the invention separately collects the mother liquor wastewater generated in the production workshop according to the water quality, controls the flow rate respectively, adjusts the content ratio of metal ions and phosphorus in the mixed sedimentation tank, ensures that the effect of sedimentation of the metal ions in the pretreatment process is better, and reduces or avoids the scaling of pipelines and water pump impellers and the fouling situation of a reverse osmosis membrane device.
After the mother liquor water in the anhydrous ferric phosphate production workshop is singly collected according to the water quality, an oversized regulating tank is not required to serve as a homogeneous water body, the sum of the volumes of the synthetic mother liquor collecting tank and the ageing mother liquor collecting tank can be smaller than that of the original mother liquor regulating tank, and the occupied area of a water tank is reduced.
The phosphorus resource is fully utilized, and the extreme situations that metal ions cannot be completely precipitated (equipment is blocked and scaled) and the phosphorus content is rich after the metal ions are precipitated are avoided when two mother liquor water qualities are different and mixed and precipitated.
Drawings
FIG. 1 is a flow chart of the iron phosphate mother liquor wastewater treatment of the present invention;
FIG. 2 is a schematic diagram of the structure of the ferric phosphate mother liquor wastewater treatment system of the present invention;
FIG. 3 is a schematic diagram of the tubular microfiltration system of the ferric phosphate mother liquor wastewater treatment system of the present invention;
fig. 4 is a schematic structural diagram of a reverse osmosis membrane device of the iron phosphate mother liquor wastewater treatment system of the present invention.
Description of the embodiments
The invention relates to a method for treating iron phosphate mother liquor wastewater, which comprises the steps of respectively introducing two strands of mother liquor into two water collecting tanks, arranging a flowmeter and an electric regulating valve at the outlet of a water feeding pump to control the water yield, mixing mother liquor water with different water qualities according to a proportion, controlling the content proportion of multivalent metal ions and phosphorus in the mother liquor water to be optimal, carrying out chemical precipitation at the moment, enabling the removal rate of multivalent metal ions in the mixed mother liquor wastewater to be higher, and dehydrating generated precipitate to be used as a slow-release fertilizer and recycling phosphorus resources in the mother liquor wastewater water treatment range of the anhydrous iron phosphate production process.
As shown in fig. 1, the method for treating the iron phosphate mother liquor wastewater specifically comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop into a synthetic mother liquor collecting tank and an aging mother liquor collecting tank according to different water qualities;
and a second step of: the two strands of mother liquor are introduced into the primary mixing reaction tank by a lifting pump, and the flow of the two strands of mother liquor is controlled by an electric regulating valve, so that the metal ion content and the phosphorus content in the primary mixing reaction tank are mixed and flow into the primary mixing reaction tank to reach the corresponding proportion: mg is p=1:2.6-3, mn is p=1:2-2.2, fe is p=1:1.1, the content of phosphorus in water is the sum of the ion proportions, ammonia water is added by an ammonia adding device when the water flows through a pipeline mixer on a main pipeline, the pH value of the discharged water is controlled to be 5.0-6.0, the hydraulic retention time is 30-60 min, and polyvalent metal ions in the water are removed by chemical precipitation;
and a third step of: the first-stage mixing reaction tank is provided with a stirring device, the bottom of the first-stage mixing reaction tank is provided with an acid-resistant and corrosion-resistant pump, the muddy water mixed solution in the water tank is conveyed into a diaphragm plate-and-frame filter press for muddy water separation, the produced sludge is conveyed into a paddle dryer for dehydration and drying after being pressed by a plate frame, the sludge is recycled as slow-release phosphate fertilizer, and filtered clear liquid enters a first-stage filtrate collecting tank;
fourth step: lifting clear liquid in the primary filtrate tank to a secondary mixing reaction tank by using a lifting pump, adding ammonia water by an ammonia adding device when flowing through a pipeline mixer of a main pipeline, controlling the pH value to be 8.5-9.0, and removing other metal ions after the hydraulic retention time is 15-30 min;
fifth step: conveying the muddy water mixed solution of the secondary mixed reaction tank into a plate-and-frame filter press by an acid-resistant and corrosion-resistant pump for muddy water separation, and conveying the generated sludge into a paddle dryer for dehydration and drying after plate-and-frame squeezing, wherein the components mainly comprise magnesium ammonium phosphate and can be recycled as slow-release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: lifting water in a water tank in mother liquor into a tubular microfiltration system by using a lifting pump, wherein the tubular microfiltration system comprises a feeding reaction tank, a water supply pump, a tubular microfiltration concentrate tank and a circulating pump, a tubular microfiltration membrane is arranged in the water tank in the mother liquor, water produced in the water tank circulates in the tubular microfiltration system, water produced in the water tank enters a tubular microfiltration water producing tank, concentrated water circulates in the tubular microfiltration system, ammonia is added for precipitation and then enters the tubular microfiltration concentrate tank, a bottom muddy water mixed solution conveying pump is conveyed to a plate-and-frame filter press, and filtered solution returns to the feeding reaction tank;
seventh step: and lifting the water in the tubular micro-filtration water producing pool to a reverse osmosis membrane device by using a lifting pump, wherein the reverse osmosis device comprises a high-pressure reverse osmosis membrane group, an ultrahigh-pressure reverse osmosis membrane group, the lifting pump, the high-pressure pump and a security filter. Concentrating the tube-type microfiltration produced water by a membrane device, taking the produced water as reuse water, wherein the electric conductivity is less than or equal to 50 mu s/cm, the salt content of the concentrated water is high, and entering an MVR evaporation device;
eighth step: after high-salt concentrated water entering the MVR device is evaporated and concentrated, the temperature of the water body is increased, the density is increased, when the density reaches 1.38-1.5 g/cm, the concentrated crystal mixed liquid is pumped into a centrifugal machine, salt is separated by the centrifugal machine, and a salt product is ammonium sulfate.
According to the method for treating the wastewater of the ferric phosphate mother liquor, disclosed by the invention, the mother liquor wastewater generated in the production process of the anhydrous ferric phosphate is collected separately according to different water qualities, and the maximum proportion of metal ions and phosphorus content in a mixed water body is controlled by artificial interference, so that the pretreatment effect of the mother liquor is better, the application range is wide, and even if the water quality of a workshop is changed, the sewage treatment system is not influenced; the pretreatment method of the mother liquor is compared with the same homogenizing regulating tank, and under the condition that other coagulation and flocculation medicaments are not added, the metal ion content in the water body can be reduced to the minimum, the scaling of pipelines and water pump impellers and the fouling and blocking of a membrane system during the operation and maintenance of a sewage treatment system are avoided to the maximum extent, and the cost of the operation and maintenance in the later period is reduced.
As shown in fig. 2, the ferric phosphate mother liquor wastewater treatment system adopting the treatment method comprises a mother liquor collecting tank 1, a primary pretreatment system 2, a secondary pretreatment system 3, a pond 4 in mother liquor, a tubular micro-filtration system 5, a reverse osmosis membrane device 6, an MVR evaporation device 7, a centrifugal machine 8 and a paddle dryer 9.
The mother liquor collecting tank 1 comprises a synthetic mother liquor collecting tank 11 and an aging mother liquor collecting tank 12; the synthesis mother liquor collecting tank 11 is used for collecting synthesis mother liquor; the aging mother liquor collecting tank 12 is used for collecting the aging mother liquor.
The primary pretreatment system 2 comprises a primary mixing reaction tank 21, a primary diaphragm plate-and-frame filter press 22 and a primary filtrate collecting tank 23;
the primary mixing reaction tank 21 is used for mixing the synthetic mother solution and the aging mother solution, and comprises a water inlet pipeline and a water outlet pipeline, wherein the water inlet pipeline comprises a main pipeline, and a first branch and a second branch which are respectively connected with the synthetic mother solution collecting tank and the aging mother solution collecting tank; the main pipeline is provided with a pipeline mixer and an ammonia adding device; the first branch and the second branch are respectively provided with an electric flow regulating valve for regulating the flow of two mother liquor water; a stirring device and an acid-resistant and corrosion-resistant pump are arranged in the primary mixing reaction tank;
an inlet of the first-stage diaphragm plate-and-frame filter press 22 is connected with an outlet pipeline of the first-stage mixing reaction tank, and an outlet end of the first-stage diaphragm plate-and-frame filter press is provided with a sludge conveying pipeline and a filtered clear liquid outlet pipeline;
the primary filtrate collecting tank 23 is used for collecting filtered clear liquid of the primary diaphragm plate-and-frame filter press, and the inlet is connected with a filtered clear liquid outlet pipeline of the primary diaphragm plate-and-frame filter press.
The secondary pretreatment system 3 comprises a secondary mixing reaction tank 31 and a secondary diaphragm plate-and-frame filter press 32;
the secondary mixing reaction tank 31 is used for removing metal ions, a water inlet pipeline is connected with an outlet of the primary filtrate collecting tank, and a pipeline mixer and an ammonia adding device are arranged on the water inlet pipeline; a stirring device is arranged in the secondary mixing reaction tank, and an acid-resistant and corrosion-resistant pump is arranged at the bottom of the secondary mixing reaction tank;
the inlet of the second-stage diaphragm plate-and-frame filter press 32 is connected with the water outlet pipeline of the second-stage mixing reaction tank, and the outlet end is provided with a sludge conveying pipeline and a filtered clear liquid water outlet pipeline.
And the mother liquor pond 4 is used for collecting filtered clear liquid of the secondary diaphragm plate-and-frame filter press 32, and the inlet is connected with a filtered clear liquid outlet pipeline of the secondary diaphragm plate-and-frame filter press 32.
The tubular micro-filtration system 5 is used for micro-filtering the water in the mother liquor; as shown in fig. 3, the tubular micro-filtration system 5 comprises a feeding reaction tank 51, a water supply pump 52, a tubular micro-filtration concentrate tank 53, a circulating pump 54, a tubular micro-filtration membrane 55 and a tubular micro-filtration water producing pool 56 which are connected in sequence; the water outlet end of the pipe type micro-filtration concentrated solution tank 53 is respectively connected with the inlets of the feeding reaction tank 51, the circulating pump 54 and the secondary diaphragm plate-and-frame filter press 32, and a pipe type micro-filtration sludge pond 57 is arranged between the pipe type micro-filtration concentrated solution tank 53 and the secondary diaphragm plate-and-frame filter press 32; the water outlet end of the tubular micro-filtration membrane 55 is respectively connected with a tubular micro-filtration water producing tank 56 and a tubular micro-filtration concentrated solution tank 53.
The reverse osmosis membrane device 6 is used for concentrating the pipe type micro-filtration water production and is connected with the pipe type micro-filtration water production pool 56 of the pipe type micro-filtration system 5; as shown in fig. 4, the reverse osmosis membrane apparatus 6 comprises a high pressure reverse osmosis membrane group 61, a high pressure reverse osmosis water producing tank 62, a high pressure reverse osmosis concentrated water tank 63, an ultra-high pressure reverse osmosis membrane group 64, and a terminal reverse osmosis membrane group 65;
the inlet end of the high-pressure reverse osmosis membrane group 61 is connected with a tubular micro-filtration water producing pool 56, and a lifting pump, a high-pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the tubular micro-filtration water producing pool 56 to the high-pressure reverse osmosis membrane group 61;
an inlet of the high-pressure reverse osmosis water producing pool 62 is connected with a produced water outlet of the high-pressure reverse osmosis membrane group 61;
the inlet of the high-pressure reverse osmosis concentrated water tank 63 is respectively connected with concentrated water outlets of the high-pressure reverse osmosis membrane group 61 and the terminal reverse osmosis membrane group 65;
the inlet of the ultra-high pressure reverse osmosis membrane group 64 is connected with the high pressure reverse osmosis concentrated water tank 63, and a lifting pump, a high pressure pump and a security filter are sequentially arranged on the water inlet pipeline from the high pressure reverse osmosis concentrated water tank 63 to the ultra-high pressure reverse osmosis membrane group 64; the water outlet of the ultrahigh pressure reverse osmosis membrane set 64 is connected with the tubular microfiltration water producing pool 56, and the concentrated water outlet is connected with the MVR evaporation device 7;
the inlet of the terminal reverse osmosis membrane group 65 is connected with the high-pressure reverse osmosis water producing tank 62, and the lifting pump, the high-pressure pump and the security filter are sequentially arranged on the water inlet pipeline of the terminal reverse osmosis membrane group 65 in the high-pressure reverse osmosis water producing tank 62; the produced water of the terminal reverse osmosis membrane group 65 is recycled, and the concentrated water outlet is connected with the inlet of the high-pressure reverse osmosis concentrated water tank 63.
The inlet of the MVR evaporation device 7 is connected with the concentrated water outlet of the ultra-high pressure reverse osmosis membrane group 64 of the reverse osmosis membrane device 6; high-pressure reverse osmosis (more than or equal to 12 Mpa) concentrated water is introduced into a concentrated liquid pool, the concentrated water is introduced into an MVR evaporation device 7 through a lifting pump, and salt crystallization is separated out through evaporation concentration by lifting density.
And a centrifuge 8 for separating salt from the crystal mixture concentrated by the MVR evaporator 7.
And the paddle dryer 9 is used for recycling sludge generated by dehydration and drying as slow release fertilizer, and the inlet is respectively connected with sludge conveying pipelines of the first-stage diaphragm plate-and-frame filter press 22 and the second-stage diaphragm plate-and-frame filter press 32.
The treatment system disclosed by the invention uses the tubular micro-filtration membrane as a front-end treatment device of the reverse osmosis system, the tubular micro-filtration membrane adopts the ceramic membrane, the pressure requirement on the tubular micro-filtration membrane during operation is smaller and is generally lower than 4X 10-4 Pa, and the tubular micro-filtration membrane is safe and stable in operation, compared with the traditional ultra-filtration membrane which adopts a hollow fiber membrane, the operation pressure is generally 4X 10-4 Pa to 7X 10-5 Pa, the membrane is not easy to block in time during cleaning, and membrane filaments are easy to break when the water pressure difference of the produced water is overlarge, so that the tubular micro-filtration system has great advantages.
The invention will be further illustrated with reference to specific examples.
Example 1
The system of the invention is adopted, and the specific processing method comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop into a synthetic mother liquor collecting tank and an aging mother liquor collecting tank according to different water qualities;
and a second step of: introducing two strands of mother liquor into a primary mixing reaction tank by a lifting pump, controlling the flow of the two strands of mother liquor by an electric regulating valve, mixing the two strands of mother liquor and flowing into the primary mixing reaction tank, enabling the metal ion content and the phosphorus content in the water to reach Mg: P=1:2.6, mn: P=1:2, fe: P=1:1.1, and enabling the water phosphorus content to be the sum of the ion proportions, when the water flows through a pipeline mixer on a main pipeline, adding ammonia water by an ammonia adding device, controlling the pH value of effluent to be 6.0, controlling the hydraulic retention time to be 30min, and removing multivalent metal ions in the water by chemical precipitation;
and a third step of: the first-stage mixing reaction tank is provided with a stirring device, the bottom of the first-stage mixing reaction tank is provided with an acid-resistant and corrosion-resistant pump, the muddy water mixed solution in the water tank is conveyed into a diaphragm plate-and-frame filter press for muddy water separation, the produced sludge is conveyed into a paddle dryer for dehydration and drying after being pressed by a plate frame, the sludge is recycled as slow-release phosphate fertilizer, and filtered clear liquid enters a first-stage filtrate collecting tank;
fourth step: lifting clear liquid in the primary filtrate tank to a secondary mixing reaction tank by using a lifting pump, adding ammonia water by an ammonia adding device when flowing through a pipeline mixer of a main pipeline, controlling the pH value to be 9.0, and removing other metal ions after the hydraulic retention time is 20 min;
fifth step: conveying the muddy water mixed solution of the secondary mixed reaction tank into a plate-and-frame filter press by an acid-resistant and corrosion-resistant pump for muddy water separation, and conveying the generated sludge into a paddle dryer for dehydration and drying after plate-and-frame squeezing, wherein the components mainly comprise magnesium ammonium phosphate and can be recycled as slow-release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: lifting water in a water tank in mother liquor into a tubular microfiltration system by using a lifting pump, wherein the tubular microfiltration system comprises a feeding reaction tank, a water supply pump, a tubular microfiltration concentrate tank and a circulating pump, a tubular microfiltration membrane is arranged in the water tank in the mother liquor, water produced in the water tank circulates in the tubular microfiltration system, water produced in the water tank enters a tubular microfiltration water producing tank, concentrated water circulates in the tubular microfiltration system and is subjected to ammonia adding precipitation, a mud-water mixture enters the tubular microfiltration concentrate tank, a bottom mud-water mixed solution conveying pump is conveyed to a secondary plate-and-frame filter press, and filtering liquid of the tubular microfiltration concentrate tank returns to the feeding reaction tank;
seventh step: and lifting the water in the tubular micro-filtration water producing pool to a reverse osmosis membrane device by using a lifting pump, wherein the reverse osmosis device comprises a high-pressure reverse osmosis membrane group, an ultrahigh-pressure reverse osmosis membrane group, the lifting pump, the high-pressure pump and a security filter. Concentrating the tube-type microfiltration produced water by a membrane device, taking the produced water as reuse water, and enabling the concentrated water to enter an MVR evaporation device, wherein the salt content of the concentrated water is high;
eighth step: after the high-salt concentrated water entering the MVR device is concentrated by evaporation, the temperature of the water body is increased, the density is increased, when the density reaches 1.38g/cm, the concentrated crystal mixed solution is pumped into a centrifugal machine, salt is separated by the centrifugal machine, and the salt product is ammonium sulfate.
Sample detection data for example 1 are shown in table 1:
table 1 sample test data of example 1
。
Example 2
The system of the invention is adopted, and the specific processing method comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop into a synthetic mother liquor collecting tank and an aging mother liquor collecting tank according to different water qualities;
and a second step of: introducing two strands of mother liquor into a primary mixing reaction tank by a lifting pump, controlling the flow of the two strands of mother liquor by an electric regulating valve, so that the ratio of metal ion content to phosphorus content in water mixed and flowing into the primary mixing reaction tank is Mg: P=1:3, mn: P=1:2.2, fe: P=1:1.1, and the phosphorus content in water is the sum of the ion ratios, adding ammonia water by an ammonia adding device when the water flows through a pipeline mixer on a main pipeline, controlling the pH value of effluent to be 5.0, controlling the hydraulic retention time to be 40min, and removing multivalent metal ions in the water by chemical precipitation;
and a third step of: the mud-water mixed liquid in the first-stage mixing reaction tank is conveyed into a first-stage diaphragm plate-and-frame filter press to carry out mud-water separation, after the plate-and-frame pressing, the produced sludge is conveyed into a paddle dryer to be dehydrated and dried, and the sludge is recovered as slow-release phosphate fertilizer, and filtered clear liquid enters a first-stage filtrate collecting tank;
fourth step: lifting clear liquid in the primary filtrate tank to a secondary mixing reaction tank by using a lifting pump, adding ammonia water by an ammonia adding device when flowing through a pipeline mixer of a main pipeline, controlling the pH value to be 8.5, and removing other metal ions after the hydraulic retention time is 30 min;
fifth step: conveying the muddy water mixed solution of the secondary mixed reaction tank into a plate-and-frame filter press by an acid-resistant and corrosion-resistant pump for muddy water separation, and conveying the generated sludge into a paddle dryer for dehydration and drying after plate-and-frame squeezing, wherein the components mainly comprise magnesium ammonium phosphate and can be recycled as slow-release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: lifting water in a water tank in mother liquor into a tubular microfiltration system by using a lifting pump, wherein the tubular microfiltration system comprises a feeding reaction tank, a water supply pump, a tubular microfiltration concentrate tank and a circulating pump, a tubular microfiltration membrane is arranged in the water tank in the mother liquor, water produced in the water tank circulates in the tubular microfiltration system, water produced in the water tank enters a tubular microfiltration water producing tank, concentrated water circulates in the tubular microfiltration system, the concentrated water enters the tubular microfiltration concentrate tank after the concentration is improved, a bottom muddy water mixed liquid conveying pump is conveyed to a plate-and-frame filter press, and filtered liquid returns to the feeding reaction tank;
seventh step: lifting water in a pipe-type micro-filtration water producing pool to a reverse osmosis membrane device by using a lifting pump, wherein the reverse osmosis device comprises a high-pressure reverse osmosis membrane group, an ultrahigh-pressure reverse osmosis membrane group, a lifting pump, a high-pressure pump and a security filter; concentrating the tube-type microfiltration produced water by a membrane device, taking the produced water as reuse water, and enabling the concentrated water to enter an MVR evaporation device, wherein the salt content of the concentrated water is high;
eighth step: after the high-salt concentrated water entering the MVR device is concentrated by evaporation, the temperature of the water body is increased, the density is increased, when the density reaches 1.40g/cm, the concentrated crystal mixed liquid is pumped into a centrifugal machine, salt is separated by the centrifugal machine, and the salt product is ammonium sulfate.
Sample detection data for example 2 are shown in table 2:
table 2 sample test data of example 2
。
Example 3
The system of the invention is adopted, and the specific processing method comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop into a synthetic mother liquor collecting tank and an aging mother liquor collecting tank according to different water qualities;
and a second step of: introducing two strands of mother liquor water into a primary mixing reaction tank by a lifting pump, controlling the flow of the water by adopting an electric regulating valve, so that the ratio of metal ion content to phosphorus content in the water mixed and flowing into the primary mixing reaction tank is Mg: P=1:2.8, mn: P=1:2.1, fe: P=1:1.1, and the phosphorus content in the water quality is the sum of the ion ratios, adding ammonia water by an ammonia adding device when the water flows through a pipeline mixer on a main pipeline, controlling the pH value of the water to be 5.5, controlling the hydraulic retention time to be 30min, and removing multivalent metal ions in the water by chemical precipitation;
and a third step of: the first-stage mixing reaction tank is provided with a stirring device, the bottom of the first-stage mixing reaction tank is provided with an acid-resistant and corrosion-resistant pump, the muddy water mixed solution in the water tank is conveyed into a diaphragm plate-and-frame filter press for muddy water separation, the produced sludge is conveyed into a paddle dryer for dehydration and drying after being pressed by a plate frame, the sludge is recycled as slow-release phosphate fertilizer, and filtered clear liquid enters a first-stage filtrate collecting tank;
fourth step: lifting clear liquid in the primary filtrate tank to a secondary mixing reaction tank by using a lifting pump, adding ammonia water by an ammonia adding device when flowing through a pipeline mixer of a main pipeline, controlling the pH value to be 8.9, and removing other metal ions after the hydraulic retention time is 15 min;
fifth step: conveying the muddy water mixed solution of the secondary mixed reaction tank into a plate-and-frame filter press by an acid-resistant and corrosion-resistant pump for muddy water separation, and conveying the generated sludge into a paddle dryer for dehydration and drying after plate-and-frame squeezing, wherein the components mainly comprise magnesium ammonium phosphate and can be recycled as slow-release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: lifting water in a water tank in mother liquor into a tubular micro-filtration system by using a lifting pump, circulating water in the water tank in the mother liquor in the tubular micro-filtration system, enabling produced water to enter a tubular micro-filtration water producing tank, and circulating concentrated water in the tubular micro-filtration system;
seventh step: lifting water in a pipe-type micro-filtration water producing pool to a reverse osmosis membrane device by using a lifting pump, concentrating the pipe-type micro-filtration water producing by using the membrane device, using the water producing water as reuse water, and enabling the concentrated water to have high salt content and enter an MVR evaporation device;
eighth step: and (3) evaporating and concentrating the high-salt concentrated water entering the MVR device, and when the density reaches 1.42g/cm, pumping the concentrated crystal mixed solution into a centrifugal machine, and separating salt by the centrifugal machine.
Sample detection data for example 3 are shown in table 3:
TABLE 3 sample detection data for example 3
。
Example 4
The system of the invention is adopted, and the specific processing method comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop into a synthetic mother liquor collecting tank and an aging mother liquor collecting tank according to different water qualities;
and a second step of: the two strands of mother liquor are introduced into a primary mixing reaction tank by a lifting pump, and the flow of the two strands of mother liquor is controlled by an electric regulating valve, so that the ratio of the metal ion content to the phosphorus content of the water mixed and flowing into the primary mixing reaction tank is as follows: the water quality phosphorus content is the sum of the ion proportions, when the water flows through a pipeline mixer on a main pipeline, ammonia water is added by an ammonia adding device, the pH value of the discharged water is controlled to be 5.6, the hydraulic retention time is 60min, and multivalent metal ions in the water are removed by chemical precipitation;
and a third step of: the first-stage mixing reaction tank is provided with a stirring device, the bottom of the first-stage mixing reaction tank is provided with an acid-resistant and corrosion-resistant pump, the muddy water mixed solution in the water tank is conveyed into a diaphragm plate-and-frame filter press for muddy water separation, the produced sludge is conveyed into a paddle dryer for dehydration and drying after being pressed by a plate frame, the sludge is recycled as slow-release phosphate fertilizer, and filtered clear liquid enters a first-stage filtrate collecting tank;
fourth step: lifting clear liquid in the primary filtrate tank to a secondary mixing reaction tank by using a lifting pump, adding ammonia water by an ammonia adding device when flowing through a pipeline mixer of a main pipeline, controlling the pH value to be 8.7, and removing other metal ions after the hydraulic retention time is 25 min;
fifth step: the mud-water mixed solution of the secondary mixing reaction tank is conveyed to a plate-and-frame filter press for mud-water separation, and after the plate-and-frame filter press, the produced sludge is conveyed to a paddle dryer for dehydration and drying, and the main component of the sludge is magnesium ammonium phosphate which can be recycled as slow release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: lifting water in a water tank in mother liquor into a tubular micro-filtration system by using a lifting pump, circulating water in the water tank in the mother liquor in the tubular micro-filtration system, enabling produced water to enter a tubular micro-filtration water producing tank, and circulating concentrated water in the tubular micro-filtration system;
seventh step: lifting water in a pipe-type micro-filtration water producing pool to a reverse osmosis membrane device by using a lifting pump, concentrating the pipe-type micro-filtration water producing by using the membrane device, using the water producing water as reuse water, and enabling the concentrated water to have high salt content and enter an MVR evaporation device;
eighth step: and (3) evaporating and concentrating the high-salt concentrated water entering the MVR device, and when the density reaches 1.40g/cm, pumping the concentrated crystal mixed solution into a centrifugal machine, and separating salt by the centrifugal machine.
Claims (2)
1. The method for treating the iron phosphate mother liquor wastewater comprises the steps of respectively introducing two mother liquor into two water collecting tanks, controlling the water yield of the two water collecting tanks, mixing mother liquor water with different water qualities, controlling the content ratio of multivalent metal ions and phosphorus in the mother liquor water to be Mg:P=1:2.6-3, mn:P=1:2-2.2, fe:P=1:1.1 and the content of water quality phosphorus to be the sum of the ion ratios, performing chemical precipitation to remove the multivalent metal ions in the mixed mother liquor wastewater, reducing the multivalent metal ions to below 5ppm, dehydrating the generated precipitate, and recovering the precipitate as slow-release fertilizer and phosphorus resources, and recycling the produced water;
the ferric phosphate mother liquor wastewater treatment method specifically comprises the following steps:
the first step: respectively collecting mother liquor water of an anhydrous ferric phosphate production workshop according to different water qualities;
and a second step of: introducing two mother liquor water flows into a primary mixing reaction tank, controlling the flow rates of the two mother liquor water flows in the primary mixing reaction tank, controlling the ratio of metal ion content to phosphorus content in water after the two mother liquor water flows into the primary mixing reaction tank in a mixing way to be Mg:P=1:2.6-3, mn:P=1:2-2.2, fe:P=1:1.1, controlling the pH value of water to be 5.5-6.0, controlling the hydraulic retention time to be 30-60 min, and removing multivalent metal ions in water by chemical precipitation;
and a third step of: performing mud-water separation on mud-water mixed liquid in the primary mixing reaction tank, squeezing a plate frame, and dehydrating and drying the generated sludge to be recycled as slow-release phosphate fertilizer;
fourth step: the filtered clear liquid in the third step is lifted to a secondary mixing reaction tank, ammonia water is added, the pH value is controlled to be 8.5-9.0, the hydraulic retention time is 15-30 min, and the rest metal ions are removed;
fifth step: carrying out mud-water separation on mud-water mixed liquid in the secondary mixing reaction tank, squeezing a plate frame, dehydrating and drying the generated sludge, wherein the components mainly comprise magnesium ammonium phosphate, and recycling the magnesium ammonium phosphate as slow release fertilizer; filtering clear liquid and then entering a pool in mother liquor;
sixth step: the water in a water tank in the mother liquor enters a tubular micro-filtration cycle, the produced water enters the next step, and the concentrated water continues the tubular micro-filtration cycle;
seventh step: the produced water in the sixth step is concentrated by a reverse osmosis membrane, and the produced water is used as reuse water;
eighth step: the seventh step of evaporating and concentrating MVR to obtain concentrated crystal mixture with concentration of 1.38-1.42 g/cm and centrifugally separating salt to obtain ammonium sulfate as salt product;
in the sixth step, concentrated water circulates through pipe type micro-filtration, after ammonia addition and precipitation, mud-water mixture is subjected to mud-water separation plate frame squeezing, and filtered liquid returns to pipe type micro-filtration circulation.
2. An iron phosphate mother liquor wastewater treatment system, which adopts the iron phosphate mother liquor wastewater treatment method as set forth in claim 1, and is characterized in that: the treatment system comprises a mother liquor collecting tank, a primary pretreatment system, a secondary pretreatment system, a mother liquor middle water tank, a tubular micro-filtration system, a reverse osmosis membrane device, an MVR evaporation device, a centrifuge and a paddle dryer;
the mother liquor collecting tank comprises a synthetic mother liquor collecting tank and an aging mother liquor collecting tank;
the primary pretreatment system comprises a primary mixing reaction tank, a primary diaphragm plate-and-frame filter press and a primary filtrate collecting tank;
the primary mixing reaction tank is used for mixing the synthesis mother liquor and the aging mother liquor and comprises a water inlet pipeline and a water outlet pipeline; the water inlet pipeline comprises a main pipeline, and a first branch and a second branch which are respectively connected with the synthetic mother liquor collecting tank and the aging mother liquor collecting tank; a pipeline mixer and an ammonia adding device are arranged on the primary mixing reaction tank main pipeline; the first branch and the second branch are respectively provided with an electric flow regulating valve for regulating the flow of two mother liquor water; a stirring device and an acid-resistant and corrosion-resistant pump are arranged in the primary mixing reaction tank;
the inlet of the primary diaphragm plate-and-frame filter press is connected with the water outlet pipeline of the primary mixing reaction tank, and the outlet end of the primary diaphragm plate-and-frame filter press is provided with a sludge conveying pipeline and a filtered clear liquid water outlet pipeline;
the first-stage filtrate collecting tank is used for collecting filtered clear liquid of the first-stage diaphragm plate-and-frame filter press, and the inlet is connected with a filtered clear liquid outlet pipeline of the first-stage diaphragm plate-and-frame filter press;
the secondary pretreatment system comprises a secondary mixing reaction tank and a secondary diaphragm plate-and-frame filter press;
the secondary mixing reaction tank is used for removing metal ions, and the water inlet pipeline is connected with the outlet of the primary filtrate collecting tank; a stirring device is arranged in the secondary mixing reaction tank, an acid-resistant and corrosion-resistant pump is arranged at the bottom of the secondary mixing reaction tank, and a pipeline mixer and an ammonia adding device are arranged on a water inlet pipeline;
the inlet of the secondary diaphragm plate-and-frame filter press is connected with the water outlet pipeline of the secondary mixing reaction tank, and the outlet end of the secondary diaphragm plate-and-frame filter press is provided with a sludge conveying pipeline and a filtered clear liquid water outlet pipeline;
the mother liquor water tank is used for collecting filtered clear liquid of the secondary diaphragm plate-and-frame filter press, and the inlet is connected with a filtered clear liquid outlet pipeline of the secondary diaphragm plate-and-frame filter press;
the tubular micro-filtration system is used for micro-filtration of water in the mother liquor;
the reverse osmosis membrane device is used for concentrating pipe type micro-filtration produced water and is connected with the pipe type micro-filtration system;
the inlet of the MVR evaporation device is connected with the concentrated water outlet of the ultra-high pressure reverse osmosis membrane group of the reverse osmosis membrane device;
the centrifugal machine is used for centrifugally separating salt from the crystallized mixed solution after being concentrated by the MVR evaporation device;
the inlet of the paddle dryer is respectively connected with sludge conveying pipelines of the primary diaphragm plate-and-frame filter press and the secondary diaphragm plate-and-frame filter press;
the tubular microfiltration system comprises a feeding reaction tank, a water supply pump, a tubular microfiltration concentrated solution tank, a circulating pump, a tubular microfiltration membrane and a tubular microfiltration water producing pool which are connected in sequence;
the water outlet end of the tubular microfiltration concentrated solution tank is respectively connected with inlets of the feeding reaction tank, the circulating pump and the secondary diaphragm plate-and-frame filter press;
the water outlet end of the tubular microfiltration membrane is respectively connected with the tubular microfiltration water producing pool and the tubular microfiltration concentrate tank;
the reverse osmosis membrane device comprises a high-pressure reverse osmosis membrane group, a high-pressure reverse osmosis water producing pool, a high-pressure reverse osmosis concentrated water pool, an ultrahigh-pressure reverse osmosis membrane group and a terminal reverse osmosis membrane group;
the inlet end of the high-pressure reverse osmosis membrane group is connected with the tubular micro-filtration water producing pool, and a lifting pump, a high-pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the tubular micro-filtration water producing pool to the high-pressure reverse osmosis membrane group;
the inlet of the high-pressure reverse osmosis water producing pool is connected with the water producing outlet of the high-pressure reverse osmosis membrane group;
the inlet of the high-pressure reverse osmosis concentrated water tank is respectively connected with the concentrated water outlets of the high-pressure reverse osmosis membrane group and the terminal reverse osmosis membrane group;
the inlet of the ultra-high pressure reverse osmosis membrane group is connected with the high pressure reverse osmosis concentrated water tank, and a lifting pump, a high pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the high pressure reverse osmosis concentrated water tank to the ultra-high pressure reverse osmosis membrane group; the water outlet of the ultrahigh pressure reverse osmosis membrane group is connected with the tubular microfiltration water producing pool, and the concentrated water outlet is connected with the MVR evaporation device;
the inlet of the terminal reverse osmosis membrane group is connected with the high-pressure reverse osmosis water producing tank, and a lifting pump, a high-pressure pump and a security filter are sequentially arranged on a water inlet pipeline from the high-pressure reverse osmosis water producing tank to the terminal reverse osmosis membrane group; and the produced water of the terminal reverse osmosis membrane group is recycled, and the concentrated water outlet is connected with the inlet of the high-pressure reverse osmosis concentrated water tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211082185.6A CN115465991B (en) | 2022-09-06 | 2022-09-06 | Ferric phosphate mother liquor wastewater treatment method and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211082185.6A CN115465991B (en) | 2022-09-06 | 2022-09-06 | Ferric phosphate mother liquor wastewater treatment method and system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115465991A CN115465991A (en) | 2022-12-13 |
| CN115465991B true CN115465991B (en) | 2023-09-19 |
Family
ID=84370590
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211082185.6A Active CN115465991B (en) | 2022-09-06 | 2022-09-06 | Ferric phosphate mother liquor wastewater treatment method and system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115465991B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108675529A (en) * | 2018-04-20 | 2018-10-19 | 深圳市华虹清源环保科技有限公司 | A method of the phosphatic waste water of processing |
| CN208151007U (en) * | 2017-11-10 | 2018-11-27 | 浙江威明环境科技有限公司 | Desulfurization wastewater Zero discharging system |
| CN109437463A (en) * | 2018-12-29 | 2019-03-08 | 江苏卓博环保科技有限公司 | Coal calcination vanadium extraction high-salt wastewater advanced treatment and reclamation device and application method |
| CN110759532A (en) * | 2019-11-07 | 2020-02-07 | 山东鑫动能锂电科技有限公司 | High-salt concentrated water treatment process for producing iron phosphate by sodium method |
| CN111635053A (en) * | 2020-05-25 | 2020-09-08 | 深圳能源资源综合开发有限公司 | Desulfurization wastewater zero-discharge treatment system and method |
| CN113860546A (en) * | 2021-09-28 | 2021-12-31 | 四川思达能环保科技有限公司 | Treatment system and treatment method for wastewater generated in production of anhydrous iron phosphate |
| CN114105392A (en) * | 2021-12-27 | 2022-03-01 | 昆山三一环保科技有限公司 | Iron phosphate wastewater treatment method and system |
-
2022
- 2022-09-06 CN CN202211082185.6A patent/CN115465991B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN208151007U (en) * | 2017-11-10 | 2018-11-27 | 浙江威明环境科技有限公司 | Desulfurization wastewater Zero discharging system |
| CN108675529A (en) * | 2018-04-20 | 2018-10-19 | 深圳市华虹清源环保科技有限公司 | A method of the phosphatic waste water of processing |
| CN109437463A (en) * | 2018-12-29 | 2019-03-08 | 江苏卓博环保科技有限公司 | Coal calcination vanadium extraction high-salt wastewater advanced treatment and reclamation device and application method |
| CN110759532A (en) * | 2019-11-07 | 2020-02-07 | 山东鑫动能锂电科技有限公司 | High-salt concentrated water treatment process for producing iron phosphate by sodium method |
| CN111635053A (en) * | 2020-05-25 | 2020-09-08 | 深圳能源资源综合开发有限公司 | Desulfurization wastewater zero-discharge treatment system and method |
| CN113860546A (en) * | 2021-09-28 | 2021-12-31 | 四川思达能环保科技有限公司 | Treatment system and treatment method for wastewater generated in production of anhydrous iron phosphate |
| CN114105392A (en) * | 2021-12-27 | 2022-03-01 | 昆山三一环保科技有限公司 | Iron phosphate wastewater treatment method and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115465991A (en) | 2022-12-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106946395A (en) | A kind of method and device of desulfurization wastewater sub-prime crystallization treatment | |
| CN109293112B (en) | Treatment method for recycling viscose fiber acid wastewater | |
| CN115124178A (en) | Recycling treatment device and method for wastewater generated in iron phosphate production by ammonia process | |
| CN112624448A (en) | Method for treating wastewater generated in white carbon black production process by precipitation process | |
| CN101870639A (en) | Method for producing kelp mannitol with low energy consumption | |
| CN115465991B (en) | Ferric phosphate mother liquor wastewater treatment method and system | |
| CN210419601U (en) | Desulfurization waste water resourceful treatment system | |
| CN115557652B (en) | Zinc-nickel-containing wastewater recycling treatment system and method | |
| CN111960601A (en) | System and method for synchronously treating copper-containing wastewater and organic wastewater | |
| CN217709144U (en) | Ferric phosphate effluent disposal system | |
| CN115108673B (en) | Recycling process for ferric phosphate mother liquor produced by oxidation method | |
| CN216918911U (en) | Treatment system for zero discharge and recycling of lithium iron phosphate production wastewater | |
| CN216472254U (en) | Sulfuric acid process titanium white powder is washed weak waste acid membrane integration resourceful treatment system once | |
| CN110065961A (en) | A kind of system and method for calcium remover and nanofiltration membrane combined treatment evaporated waste ammonia liquid | |
| CN112624505A (en) | Treatment method and system for evaporation mother liquor of high-salt-content wastewater | |
| CN113429053A (en) | Silica gel wastewater recycling treatment method | |
| CN112062366A (en) | Coal-fired power plant desulfurization wastewater comprehensive treatment system and method | |
| CN107473488B (en) | Treatment method of para-ester production wastewater | |
| CN116282717B (en) | Comprehensive treatment method for production wastewater | |
| CN219297154U (en) | System for be used for purifying fertilizer level wet process phosphoric acid | |
| CN220265499U (en) | Ferric phosphate waste water's processing apparatus | |
| CN215924819U (en) | Sweet potato protein extraction and separation device | |
| CN219991378U (en) | Ribose, VC and derivative preparation wastewater treatment system thereof | |
| CN114988606A (en) | Treatment system and treatment method for phosphogypsum leachate and washing water in phosphorus chemical industry | |
| CN219929865U (en) | Treatment system for graphite production wastewater |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |