A phosphorus-containing waste liquid treatment synchronous phosphorus removal agent regeneration device system

Abstract

The utility model provides a kind of phosphorus-containing waste liquid treatment synchronous phosphorus removal agent regeneration device system, the phosphorus-containing waste liquid treatment synchronous phosphorus removal agent regeneration device system includes phosphorus-containing waste liquid storage device, phosphorus removal reaction device, first filter-press washing device, conversion device, second filter-press washing device, lye storage device and acid liquor storage device;The phosphorus-containing waste liquid storage device, phosphorus removal reaction device, first filter-press washing device, conversion device and second filter-press washing device are sequentially connected;The second filter-press washing device is connected with phosphorus removal reaction device;The lye storage device is connected with phosphorus removal reaction device and conversion device respectively;The acid liquor storage device is connected with phosphorus removal reaction device.The utility model entire device system structure design is reasonable, easy to operate, phosphorus-containing waste liquid treatment cost is low, realizes phosphorus removal agent regeneration reuse, and economic benefit is high.

Description

Technical Field

[0001] This utility model relates to the field of waste liquid treatment technology, and in particular to a system for simultaneous phosphorus removal agent regeneration in the treatment of phosphorus-containing waste liquid. Background Technology

[0002] Existing methods for treating phosphorus-containing wastewater commonly use ferric salts (ferric chloride / ferric sulfate / ferric nitrate, etc.) as phosphorus removal agents. The treatment yields a dephosphorized solution and phosphorus-containing iron sludge. The dephosphorized solution is evaporated and crystallized to obtain pure salt, while the phosphorus-containing iron sludge is outsourced for secondary waste disposal. However, outsourcing the disposal of phosphorus-containing iron sludge wastewater wastes phosphorus resources and requires continuous replenishment of the phosphorus removal agent, leading to increased costs and poor economic efficiency.

[0003] CN119144790A discloses a method for dephosphorizing and extracting iron from high-phosphorus iron-containing materials. This method includes the following steps: pre-reducing the high-phosphorus iron-containing material and then adding a reducing agent for a first melting separation to obtain low-phosphorus slag and high-phosphorus molten iron; adding a reducing agent and a flux to the low-phosphorus slag for a second melting separation to obtain final slag and low-phosphorus molten iron; the flux is lime and / or limestone. Its application is for phosphorus-containing iron materials, used for phosphorus removal during iron smelting, but it does not involve phosphorus recovery and resource utilization.

[0004] CN213231894U discloses a phosphate removal device for cyclohexanone ammonium oxime treatment wastewater. The device includes a wastewater inlet connected to the wastewater outlet of the stripping tower in the ammonium oxime treatment unit. By setting up a two-effect evaporation wastewater pretreatment device comprising a first-effect evaporator and a second-effect evaporator, the phosphorus-containing wastewater from the stripping tower of the ammonium oxime treatment unit is divided into concentrated wastewater and low-salt wastewater. The total phosphorus content in the low-salt wastewater is almost zero, so only the concentrated wastewater needs phosphorus removal, significantly reducing the amount of wastewater requiring phosphorus removal and improving the efficiency of phosphorus removal. The pH value of the concentrated wastewater is adjusted using acidic wastewater from the adipic acid workshop to meet the requirements for phosphorus removal with polyferric sulfate, thus reducing both the amount of acid reagent added and the amount of wastewater discharged from the adipic acid workshop, effectively lowering the cost of phosphorus removal. Using polyferric sulfate as a flocculant for flocculation and precipitation of phosphorus in the concentrated wastewater effectively removes phosphorus from the wastewater, ensuring that wastewater discharge meets environmental protection requirements. However, it only removes phosphorus and does not perform subsequent treatment of the precipitate after phosphorus removal.

[0005] CN116216676A discloses a method for hydrothermal synthesis of ferric phosphate dihydrate from iron-phosphorus waste residue. The steps are as follows: (1) First, place the iron-phosphorus waste residue in an oven at 50-80℃ and dry it for 4-6 hours, then crush and ball mill it for later use; (2) Place the iron-phosphorus waste residue obtained in (1) into a hydrothermal reactor, then add a regulator to the reactor, and finally add industrial-grade phosphoric acid and hydrogen peroxide to the reactor. After reacting at 160-180℃ for 12-24 hours, cool and filter to obtain crude ferric phosphate dihydrate and filtrate 1; after washing and drying the crude ferric phosphate dihydrate, ferric phosphate dihydrate and washing liquid 1 are obtained. It does not involve the removal of impurities in the iron-phosphorus waste residue, but only the morphological transformation under controlled iron-phosphorus conditions, and its application scope is relatively small.

[0006] Therefore, it is of great significance to develop a device system that can treat phosphorus-containing wastewater while regenerating the phosphorus removal agent. Utility Model Content

[0007] In view of the problems existing in the prior art, this utility model provides a phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater. This system achieves phosphorus separation from the wastewater by sequentially connecting a phosphorus-containing wastewater storage device, a phosphorus removal reaction device, a first pressure filtration and washing device, a conversion device, and a second pressure filtration and washing device. Furthermore, the system regenerates the phosphorus removal agent by incorporating an acid storage device. The system has a reasonable structural design, is simple to operate, and is highly economical.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] This utility model provides a system for treating phosphorus-containing waste liquid and simultaneously regenerating phosphorus removal agent. The system includes a phosphorus-containing waste liquid storage device, a phosphorus removal reaction device, a first pressure filtration and washing device, a conversion device, a second pressure filtration and washing device, an alkaline solution storage device, and an acid solution storage device.

[0010] The phosphorus-containing waste liquid storage device, the phosphorus removal reaction device, the first pressure filtration and washing device, the conversion device, and the second pressure filtration and washing device are connected in sequence.

[0011] The second pressure filtration and washing device is connected to the phosphorus removal reaction device;

[0012] The alkaline solution storage device is connected to the phosphorus removal reaction device and the conversion device, respectively.

[0013] The acid storage device is connected to the phosphorus removal reaction device.

[0014] The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system of this utility model includes a phosphorus-containing wastewater storage device, a phosphorus removal reaction device, a first pressure filtration and washing device, a conversion device, and a second pressure filtration and washing device connected in sequence. The phosphorus-containing wastewater undergoes a phosphorus removal reaction under the action of the phosphorus removal agent. After treatment by the first pressure filtration and washing device to remove water-soluble salts, a phosphorus removal solution and phosphorus removal sludge are obtained. The phosphorus removal sludge enters the conversion device to obtain ferric hydroxide and sodium phosphate solution. After treatment by the second pressure filtration and washing device, phosphorus can be fully recovered, realizing the resource utilization of phosphorus. By setting up an acid storage device, the ferric hydroxide precipitate can be dissolved and hydrolyzed by acid, thus regenerating the phosphorus removal agent.

[0015] In the phosphorus removal reaction device described in this invention, ferric hydroxide sludge produced by the second pressure filtration and washing device is first added, followed by the addition of a corresponding acid solution to dissolve the iron. Then, phosphorus-containing waste liquid is added, and finally, an alkaline solution is used to adjust the pH to 5-6 for the phosphorus removal reaction. In this invention, the pH of the phosphorus removal reaction is 5-6, at which point the solution contains fewer hydroxide ions, preferentially forming ferric phosphate precipitate. Simultaneously, the remaining iron also precipitates as ferric hydroxide, resulting in a phosphorus-free and iron-free dephosphorized solution. This dephosphorized solution can be further processed by the first evaporation and crystallization device to obtain the corresponding salt product. In the conversion device, the solution pH is controlled at 9-11, at which point the solution contains more hydroxide ions, preferentially forming ferric hydroxide precipitate, while phosphorus exists in the solution as sodium phosphate. Processing by the second evaporation and crystallization device achieves the resource recovery of phosphorus. The ferric hydroxide precipitate is dissolved using a corresponding acid solution, thus regenerating and reusing the phosphorus removal agent.

[0016] The acid solution in the acid storage device described in this invention refers to an acid solution whose composition matches that of the phosphorus-containing waste liquid, without introducing additional impurities. If the phosphorus-containing waste liquid is a sodium chloride solution containing phosphorus, hydrochloric acid is used as the acid solution; if the phosphorus-containing waste liquid is a sodium sulfate solution containing phosphorus, sulfuric acid is used as the acid solution; if the phosphorus-containing waste liquid is a sodium nitrate solution containing phosphorus, nitric acid is used as the acid solution.

[0017] Preferably, the phosphorus-containing wastewater treatment and phosphorus removal agent regeneration device system further includes a cleaning water storage device.

[0018] Preferably, the cleaning water storage device is connected to the first pressure filtration and washing device.

[0019] Preferably, the cleaning water storage device is also connected to the second pressure filter washing device.

[0020] This invention utilizes a cleaning water storage device to provide cleaning water to the first and second pressure filtration and washing devices, enabling the pressure filtration and washing devices to not only have a pressure filtration function but also a water washing function, thereby efficiently separating phosphorus-containing waste liquid and achieving resource recovery.

[0021] Preferably, the phosphorus-containing wastewater treatment and phosphorus removal agent regeneration device system further includes a first evaporation and crystallization device.

[0022] Preferably, the first evaporation crystallization device is connected to the first pressure filtration and washing device.

[0023] Preferably, the phosphorus-containing wastewater treatment and phosphorus removal agent regeneration device system further includes a second evaporation and crystallization device.

[0024] Preferably, the second evaporation crystallization device is connected to the second pressure filtration and washing device.

[0025] The first and second pressure filtration and washing devices of this invention perform pressure filtration followed by washing.

[0026] Preferably, the conversion device includes a reaction vessel.

[0027] Preferably, the phosphorus-containing waste liquid storage device is connected to the component analysis device.

[0028] Preferably, the phosphorus removal reaction device is connected to the phosphorus removal agent storage device.

[0029] The phosphorus removal agent used in this invention is an existing phosphorus removal agent, including ferric chloride, ferric sulfate, or ferric nitrate. The composition of the phosphorus-containing waste liquid is confirmed by a component analysis device. If the phosphorus-containing waste liquid contains phosphorus in sodium chloride solution, ferric chloride is used as the phosphorus removal agent; if the phosphorus-containing waste liquid contains phosphorus in sodium sulfate solution, ferric sulfate is used as the phosphorus removal agent; if the phosphorus-containing waste liquid contains phosphorus in sodium nitrate solution, ferric nitrate is used as the phosphorus removal agent.

[0030] The method of using the phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system provided by this utility model includes the following steps:

[0031] (1) After the component analysis device determines the components of the phosphorus-containing waste liquid, the corresponding phosphorus removal agent is loaded into the phosphorus removal agent storage device;

[0032] (2) The phosphorus-containing waste liquid in the phosphorus-containing waste liquid storage device and the phosphorus removal agent in the phosphorus removal agent storage device enter the phosphorus removal reaction device, and the alkali solution in the alkali solution storage device is added to adjust the pH to 5-6 to carry out the phosphorus removal reaction.

[0033] (3) The mixture after the reaction enters the first water washing and filter press device for filter press 1 to obtain the dephosphorization mud of the dephosphorization liquid; the dephosphorization mud is washed with water 1 to remove the water-soluble salts therein to obtain washing mud 1 and washing water 1; the washing water 1 is added to the dephosphorization liquid and enters the first evaporation and crystallization device to obtain the salt product; the washing water storage device provides washing water to the first water washing and filter press device.

[0034] (4) The washing mud 1 enters the conversion device, and after adjusting the pH to 9-11 with the alkali solution in the alkali storage device, it enters the second water washing and filter press device for filter press 2 to obtain sodium phosphate solution and conversion mud; the conversion mud is washed with water 2 to remove water-soluble salts, resulting in washing mud 2 and washing water 2; the washing water 2 is added to the sodium phosphate solution and enters the second evaporation and crystallization device to obtain sodium phosphate crystal product; the washing water storage device provides washing water to the second water washing and filter press device.

[0035] (5) The hydrochloric acid in the cleaning mud 2 and the acid storage device are both put into the dephosphorization reaction device for acid dissolution and reuse to obtain the regenerated dephosphorization agent.

[0036] The chemical equation for the phosphorus removal reaction in step (2) is as follows:

[0037] Fe 3+ +PO4 3- =FePO4.

[0038] The chemical reaction equation occurring in the conversion device in step (4) is as follows:

[0039] FePO4+3NaOH=Fe(OH)3+Na3PO4.

[0040] Compared with the prior art, the present invention has at least the following beneficial effects:

[0041] The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system provided by this utility model converts the precipitate obtained during phosphorus removal into sodium phosphate by setting a conversion device, thereby realizing the resource utilization of phosphorus; by setting an acid storage device, the iron sludge after phosphorus extraction is acid-dissolved, thereby realizing the regeneration of the phosphorus removal agent; the entire device system is simple to operate, has low cost for treating phosphorus-containing wastewater, and high economic benefits, making it suitable for widespread application. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system provided in a specific embodiment of this utility model.

[0043] Figure 2 This is a flowchart illustrating the usage method of the phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system provided in a specific embodiment of this utility model.

[0044] In the diagram: 1-Phosphorus-containing waste liquid storage device; 2-Phosphorus removal reaction device; 3-First pressure filtration and washing device; 4-Conversion device; 5-Second pressure filtration and washing device; 6-Alkali storage device; 7-Acid storage device; 8-Washing water storage device; 9-First evaporation and crystallization device; 10-Second evaporation and crystallization device. Detailed Implementation

[0045] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0046] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be determined by the claims.

[0047] It should be understood that in the description of this utility model, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0048] It should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0049] Those skilled in the art should understand that this utility model necessarily includes the necessary pipelines, conventional valves and general pump equipment for achieving complete process, but the above content is not the main utility model point of this utility model. Those skilled in the art can add layouts based on process flow and equipment structure selection. This utility model does not make any special requirements or specific limitations in this regard.

[0050] As a specific embodiment of this utility model, a system for simultaneous phosphorus removal agent regeneration in the treatment of phosphorus-containing wastewater is provided, the schematic diagram of which is shown below. Figure 1 As shown.

[0051] The phosphorus-containing waste liquid treatment and simultaneous phosphorus removal agent regeneration device system includes a phosphorus-containing waste liquid storage device 1, a phosphorus removal reaction device 2, a first pressure filtration and washing device 3, a conversion device 4, a second pressure filtration and washing device 5, an alkaline solution storage device 6, and an acid solution storage device 7.

[0052] The phosphorus-containing waste liquid storage device 1, the phosphorus removal reaction device 2, the first pressure filtration and washing device 3, the conversion device 4, and the second pressure filtration and washing device 5 are connected in sequence.

[0053] The second pressure filtration and washing device 5 is connected to the phosphorus removal reaction device 2;

[0054] The alkaline solution storage device 6 is connected to the phosphorus removal reaction device 2 and the conversion device 4 respectively;

[0055] The acid storage device 7 is connected to the phosphorus removal reaction device 2.

[0056] The phosphorus-containing waste liquid treatment and phosphorus removal agent regeneration device system also includes a cleaning water storage device 8.

[0057] The cleaning water storage device 8 is connected to the first pressure filter washing device 3.

[0058] The cleaning water storage device 8 is also connected to the second pressure filter washing device 5.

[0059] The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system also includes a first evaporation and crystallization device 9.

[0060] The first evaporation crystallization device 9 is connected to the first pressure filtration and washing device 3.

[0061] The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system also includes a second evaporation and crystallization device 10.

[0062] The second evaporation crystallization device 10 is connected to the second pressure filtration and washing device 5.

[0063] The conversion device 4 is a reaction vessel.

[0064] The phosphorus-containing waste liquid storage device 1 is connected to the component analysis device; the phosphorus removal reaction device 2 is connected to the phosphorus removal agent storage device.

[0065] As a specific embodiment of this utility model, a method for using the above-mentioned phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system is also provided, the flowchart of which is as follows: Figure 2 As shown, the method of use includes the following steps:

[0066] (1) The component analysis device determined that the phosphorus-containing waste liquid was sodium chloride solution containing phosphorus, and the corresponding phosphorus removal agent ferric chloride was loaded into the phosphorus removal agent storage device;

[0067] (2) The phosphorus-containing waste liquid in the phosphorus-containing waste liquid storage device 1 and the phosphorus removal agent in the phosphorus removal agent storage device enter the phosphorus removal reaction device 2, and the alkali solution in the alkali solution storage device 6 is added to adjust the pH to 5.5 for phosphorus removal reaction;

[0068] (3) The mixture after the reaction enters the first water washing and filter press 3 and is first filtered by filter press 1 to obtain the dephosphorization mud of the dephosphorization liquid; the dephosphorization mud is washed by water 1 to remove the water-soluble salts therein to obtain washing mud 1 and washing water 1; the washing water 1 is added to the dephosphorization liquid and enters the first evaporation and crystallization device 9 to obtain the salt product; the washing water storage device 8 provides washing water to the first water washing and filter press 3.

[0069] (4) The washing mud 1 enters the conversion device 4, and after adjusting the pH to 10 with the alkali solution in the alkali storage device 6, it enters the second water washing and filter press device 5 for filter press 2 to obtain sodium phosphate solution and conversion mud; the conversion mud is washed with water 2 to remove water-soluble salts to obtain washing mud 2 and washing water 2; the washing water 2 is added to the sodium phosphate solution and enters the second evaporation and crystallization device 10 to obtain sodium phosphate crystal product; the washing water storage device 8 provides washing water to the second water washing and filter press device 5.

[0070] (5) The hydrochloric acid in the cleaning mud 2 and the acid storage device 7 are both fed into the phosphorus removal reaction device 2 for acid dissolution and reuse to obtain the regenerated phosphorus removal agent ferric chloride.

[0071] In summary, the phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater provided by this utility model converts the precipitate obtained during phosphorus removal into sodium phosphate by setting up a conversion device, thereby realizing the resource utilization of phosphorus; by setting up an acid storage device, the iron sludge after phosphorus extraction is acid-dissolved, thereby realizing the regeneration of the phosphorus removal agent; the entire device system has a reasonable structural design, is simple to operate, has low cost for treating phosphorus-containing wastewater, and has high economic benefits, making it suitable for widespread application.

[0072] The applicant declares that the detailed structural features of this utility model are illustrated through the above embodiments, but this utility model is not limited to the above detailed structural features, that is, it does not mean that this utility model must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to this utility model, equivalent substitutions of selected components, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this utility model.

[0073] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

Claims

1. A system for treating phosphorus-containing wastewater and simultaneously regenerating phosphorus removal agents, characterized in that, The phosphorus-containing waste liquid treatment and simultaneous phosphorus removal agent regeneration device system includes a phosphorus-containing waste liquid storage device, a phosphorus removal reaction device, a first pressure filtration and washing device, a conversion device, a second pressure filtration and washing device, an alkaline solution storage device, and an acid solution storage device. The phosphorus-containing waste liquid storage device, the phosphorus removal reaction device, the first pressure filtration and washing device, the conversion device, and the second pressure filtration and washing device are connected in sequence. The second pressure filtration and washing device is connected to the phosphorus removal reaction device; The alkaline solution storage device is connected to the phosphorus removal reaction device and the conversion device, respectively. The acid storage device is connected to the phosphorus removal reaction device.

2. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 1, characterized in that, The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system also includes a cleaning water storage device.

3. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 2, characterized in that, The cleaning water storage device is connected to the first pressure filter washing device.

4. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 2, characterized in that, The cleaning water storage device is also connected to the second pressure filter washing device.

5. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 1, characterized in that, The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system also includes a first evaporation and crystallization device.

6. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 5, characterized in that, The first evaporation crystallization device is connected to the first pressure filtration and washing device.

7. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 1, characterized in that, The phosphorus-containing wastewater treatment and simultaneous phosphorus removal agent regeneration device system also includes a second evaporation and crystallization device.

8. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 7, characterized in that, The second evaporation crystallization device is connected to the second pressure filtration and washing device.

9. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 1, characterized in that, The conversion device includes a reaction vessel.

10. The simultaneous phosphorus removal agent regeneration device system for treating phosphorus-containing wastewater according to claim 1, characterized in that, The phosphorus-containing waste liquid storage device is connected to the component analysis device; The phosphorus removal reaction device is connected to the phosphorus removal agent storage device.

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