Secondary hardness and silicon removal wastewater treatment system

Abstract

The invention discloses a secondary hardness and silicon removal wastewater treatment system which comprises a primary silicon removal tank, a primary hardness removal tank, a secondary silicon removal high-density sedimentation tank, a secondary hardness removal high-density sedimentation tank, a secondary silicon removal water conveying pipeline and a secondary hardness removal water conveying pipeline. The flow directions of wastewater in the primary silicon removal tank, the primary hardness removal tank, the secondary silicon removal high-density sedimentation tank and the secondary hardness removal high-density sedimentation tank are switched by controlling the primary / secondary silicon removal water delivery pipeline and the primary / secondary hardness removal water delivery pipeline, and different agents are added into the tanks in combination with the agent adding system, so that the optimal reaction sequence can be tested; the operation is simple, the hardness and the silicon content of effluent can be reduced, and the treatment cost can also be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a secondary hardness and silicon removal wastewater treatment system. Background Art

[0002] At present, a large amount of industrial wastewater is generated in industrial production. The wastewater may contain a large amount of metal ions, organic matter, suspended solids, calcium-magnesium-silicon scaling factors, etc. Therefore, removing hardness and silicon from industrial wastewater is of great significance for protecting the environment, improving the recycling rate of water resources, and ensuring the stable operation of industrial equipment.

[0003] De-hardening (softening): refers to the removal of calcium ions (Ca 2+ ) and magnesium ions (Mg 2+ ), these two ions are the main components that cause water hardness. Hard water has many effects on industrial production and domestic water use. For example, in heat exchange systems, hard water can cause scaling, reduce thermal efficiency, and increase equipment maintenance costs. Common methods for removing hardness include: ion exchange (replacing calcium and magnesium ions in water through ion exchange resins), chemical precipitation (adding reagents (such as lime, soda ash, etc.) to water to form insoluble precipitates for calcium and magnesium ions to be removed), and distillation (evaporating water and condensing it for recovery to remove all dissolved solids in the water, including hardness ions).

[0004] Silicon removal: refers to the removal of silicate and its salts from water. Although the content of silicate in water is not high, when the water is heated, silicate will form insoluble silica scale, which is hard and difficult to remove. It will form deposits in boilers, heat exchangers and other equipment, reducing thermal efficiency and even causing equipment damage. Common silicon removal methods include: chemical coagulation method (adding coagulants to water to make silicate form flocculent precipitation), ion exchange method (using specific ion exchange resins to remove silicate ions in water), pretreatment and reverse osmosis method (removing silicon content in water through pretreatment (such as acid addition to adjust pH value) and reverse osmosis membrane technology).

[0005] However, the current wastewater treatment system has a high treatment cost and cannot adjust the order of silicon removal and hardness removal reactions or even the reflux order according to the type of industrial wastewater being treated, so as to obtain the optimal primary and secondary silicon removal and hardness removal treatment effects, which can not only reduce the hardness and silicon content of the effluent, but also reduce the treatment cost.

[0006] In view of this, it is necessary to provide a secondary hardness and silicon removal wastewater treatment system to overcome the above-mentioned defects, which can treat different incoming water qualities and adapt to different reagent addition methods. Summary of the invention

[0007] The purpose of the present invention is to provide a secondary hardness and silicon removal wastewater treatment system, which aims to solve the problem of how to adjust the silicon removal and hardness removal reaction sequence and even the reflux sequence for each industrial wastewater, so as to reduce the effluent hardness and silicon content and reduce the treatment cost.

[0008] In order to achieve the above object, the present invention provides a secondary hardness and silicon removal wastewater treatment system, comprising:

[0009] Primary silicon removal tank, primary hardness removal tank, secondary silicon removal high-density sedimentation tank, secondary hardness removal high-density sedimentation tank, silicon removal water production tank, hardness removal water production tank, multi-media filter;

[0010] A reagent dosing system, the reagent dosing system comprising a lime milk or liquid alkali dosing component, an aluminum agent or magnesium agent dosing component, a sodium carbonate dosing component, a flocculant dosing component, a coagulant aid dosing component, and an acid dosing component;

[0011] A primary desiliconization water pipeline, the primary desiliconization water pipeline is used to transport the wastewater treated in the primary desiliconization tank to the primary hardness removal tank or the secondary desiliconization high-density sedimentation tank;

[0012] A primary hardness removal water delivery pipeline, the primary hardness removal water delivery pipeline is used to transport the wastewater treated in the primary hardness removal tank to the primary silicon removal tank or the secondary hardness removal high-density sedimentation tank;

[0013] A secondary desiliconization water pipeline, the secondary desiliconization water pipeline is used to transport the produced water of the desiliconization water production tank to the primary hardness removal tank or the multi-media filter;

[0014] A secondary de-hardening water delivery pipeline, the secondary de-hardening water delivery pipeline is used to deliver the produced water from the de-hardening water production tank to the primary desiliconization tank or the multi-media filter;

[0015] The lime milk or liquid alkali adding component is used to add lime milk or liquid alkali solution to the primary silicon removal tank and the primary hardness removal tank respectively; the aluminum agent or magnesium agent adding component is used to add aluminum agent or magnesium agent solution to the primary silicon removal tank; the sodium carbonate adding component is used to add sodium carbonate solution to the primary hardness removal tank; the flocculant adding component is used to add flocculant solution to the secondary silicon removal high-density sedimentation tank and the secondary hardness removal high-density sedimentation tank respectively, and the coagulant adding component is used to add coagulant aid solution to the secondary silicon removal high-density sedimentation tank and the secondary hardness removal high-density sedimentation tank respectively; the acid adding component is used to add sulfuric acid or hydrochloric acid to the silicon removal water production tank and the hardness removal water production tank respectively;

[0016] A desiliconization sludge discharge pipeline, which is used to discharge the sludge produced by the secondary desiliconization high-density sedimentation tank;

[0017] A hard-sludge removal pipeline, which is used to discharge the sludge produced by the secondary hard-sludge removal high-density sedimentation tank;

[0018] The multi-media filter is used to filter the produced water of the secondary silicon removal high-density sedimentation tank or the secondary hardness removal high-density sedimentation tank.

[0019] In a preferred embodiment, it also includes a wastewater treatment pipeline, which is respectively connected to the primary silicon removal tank, the primary hardness removal tank, the secondary silicon removal high-density sedimentation tank, the secondary hardness removal high-density sedimentation tank, the silicon removal water production tank, the hardness removal water production tank, and the multi-media filter to receive the wastewater produced by each of them and discharge it into the wastewater tank.

[0020] In a preferred embodiment, the secondary silicon removal high-density sedimentation tank includes a silicon removal mixing tank, a silicon removal flocculation tank, and a silicon removal sedimentation tank; the silicon removal flocculation tank is provided with a guide tube, and the silicon removal mixing tank extends into the bottom of the guide tube through a connecting pipe; the primary silicon removal water supply pipeline is connected to the silicon removal mixing tank; the secondary hardness removal high-density sedimentation tank includes a hardness removal mixing tank, a hardness removal flocculation tank, and a hardness removal sedimentation tank; the hardness removal flocculation tank is also provided with a guide tube, and the hardness removal mixing tank also extends into the bottom of the corresponding guide tube through a connecting pipe; the primary hardness removal water supply pipeline is connected to the hardness removal mixing tank.

[0021] In a preferred embodiment, the silicon removal sludge discharge pipeline is provided with a silicon removal sludge discharge pump, and one end of the silicon removal sludge discharge pipeline is connected to the bottom of the silicon removal sedimentation tank, and the silicon removal sludge discharge pump is used to discharge the sludge precipitated in the silicon removal sedimentation tank through the silicon removal sludge discharge pipeline; the hardness removal sludge discharge pipeline is provided with a hardness removal sludge discharge pump, and one end of the hardness removal sludge discharge pipeline is connected to the bottom of the hardness removal sedimentation tank, and the hardness removal sludge discharge pump is used to discharge the sludge precipitated in the hardness removal sedimentation tank through the hardness removal sludge discharge pipeline.

[0022] In a preferred embodiment, it also includes a silicon removal sludge return pipeline and a hardness removal sludge return pipeline; the silicon removal sludge return pipeline is provided with a silicon removal sludge return pump, and one end is connected to the bottom of the silicon removal sedimentation tank, and the other end is connected to the silicon removal mixing tank; the silicon removal sludge return pump is used to pump the sludge precipitated in the silicon removal sedimentation tank through the silicon removal sludge return pipeline and return it to the silicon removal mixing tank, or to assist the silicon removal sludge pump to discharge the sludge in the silicon removal sedimentation tank; the hardness removal sludge return pipeline is provided with a hardness removal sludge return pump, and one end is connected to the bottom of the hardness removal sedimentation tank, and the other end is connected to the hardness removal mixing tank; the hardness removal sludge return pump is used to pump the sludge precipitated in the hardness removal sedimentation tank through the hardness removal sludge return pipeline and return it to the hardness removal mixing tank, or to assist the hardness removal sludge pump to discharge the sludge in the hardness removal sedimentation tank.

[0023] In a preferred embodiment, the silicon removal sludge discharge pipeline is also connected to a silicon removal sludge replenishing pipeline, and the rated power of the silicon removal sludge pump is greater than the rated power of the silicon removal sludge return pump; when the silicon removal sludge return pump stops running, part of the sludge pumped out by the silicon removal sludge pump flows back to the silicon removal mixing tank through the silicon removal sludge replenishing pipeline; the hard sludge removal discharge pipeline is also connected to a hard sludge removal replenishing pipeline, and the rated power of the hard sludge removal pump is greater than the rated power of the hard sludge removal return pump; when the hard sludge removal return pump stops running, part of the sludge pumped out by the hard sludge removal pump flows back to the hard removal mixing tank through the hard sludge replenishing pipeline.

[0024] In a preferred embodiment, the lime milk or liquid alkali dosing component includes a lime milk or liquid alkali preparation tank for preparing lime milk or liquid alkali solution and a lime milk or liquid alkali first dosing pump and a lime milk or liquid alkali second dosing pump both of which are connected to the lime milk or liquid alkali preparation tank; the lime milk or liquid alkali first dosing pump is used to pump the lime milk or liquid alkali solution into the primary desiliconization tank, and the lime milk or liquid alkali second dosing pump is used to pump the lime milk or liquid alkali solution into the primary dehardness tank;

[0025] The aluminum or magnesium agent dosing assembly includes an aluminum or magnesium agent preparation tank for preparing an aluminum or magnesium agent solution and an aluminum or magnesium agent dosing pump connected to the aluminum or magnesium agent preparation tank; the aluminum or magnesium agent dosing pump is used to pump the aluminum or magnesium agent solution into the primary desiliconization tank;

[0026] The sodium carbonate dosing assembly includes a sodium carbonate preparation tank for preparing a sodium carbonate solution and a sodium carbonate dosing pump connected to the sodium carbonate preparation tank; the sodium carbonate dosing pump is used to pump the sodium carbonate solution into the primary hardness removal tank;

[0027] The flocculant dosing component includes a flocculant preparation tank for preparing a flocculant solution, and a first flocculant dosing pump and a second flocculant dosing pump both of which are connected to the flocculant preparation tank; the first flocculant dosing pump is used to pump the flocculant solution into the silicon removal mixing tank, and the second flocculant dosing pump is used to pump the flocculant solution into the hardness removal mixing tank;

[0028] The coagulant dosing assembly includes a coagulant preparation tank for preparing a coagulant solution, and a first coagulant dosing pump and a second coagulant dosing pump both of which are connected to the coagulant preparation tank; the first coagulant dosing pump is used to pump the coagulant solution into the bottom of the guide tube of the silicon removal mixing tank and the silicon removal flocculation tank, and the second coagulant dosing pump is used to pump the coagulant solution into the bottom of the guide tube of the hardness removal mixing tank and the hardness removal flocculation tank;

[0029] The acid dosing assembly comprises an acid storage tank and an acid dosing pump connected to the acid storage tank, and the acid dosing pump is used to pump sulfuric acid or hydrochloric acid into the silicon removal water production tank and the hardness removal water production tank respectively.

[0030] In a preferred embodiment, the chemical dosing system also includes a chemical preparation water inlet pipeline; the chemical preparation water inlet pipeline is respectively connected to the lime milk or liquid alkali preparation tank, the aluminum or magnesium agent preparation tank, the sodium carbonate preparation tank, the flocculant preparation tank, and the coagulant aid preparation tank to supply water to each preparation tank separately.

[0031] The secondary hardness and silicon removal wastewater treatment system provided by the present invention controls the primary / secondary silicon removal water supply pipeline and the primary / secondary hardness removal water supply pipeline through valves to switch the flow direction of wastewater in the primary silicon removal tank, the primary hardness removal tank, the secondary silicon removal high-density sedimentation tank, and the secondary hardness removal high-density sedimentation tank. Different chemicals are added to each tank in combination with the chemical dosing system, so that the best reaction sequence can be tested. The operation is simple, and both the hardness and silicon content of the effluent water can be reduced and the treatment cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 Schematic diagram of the pipelines of a secondary hardness and silicon removal wastewater treatment system in an exemplary embodiment.

[0034] Numbers in the figure: 100, secondary hardness and silicon removal wastewater treatment system;

[0035] 10. Primary silicon removal tank; 20. Primary hardness removal tank; 30. Secondary silicon removal high-density sedimentation tank; 31. Silicon removal mixing tank; 32. Silicon removal flocculation tank; 33. Silicon removal sedimentation tank; 40. Secondary hardness removal high-density sedimentation tank; 41. Hardness removal mixing tank; 42. Hardness removal flocculation tank; 43. Hardness removal sedimentation tank; 50. Silicon removal water production tank; 60. Hardness removal water production tank; 70. Multi-media filter;

[0036] 81. Lime milk or liquid alkali dosing component; 811. Lime milk or liquid alkali preparation tank; 812. Lime milk or liquid alkali first dosing pump; 813. Lime milk or liquid alkali second dosing pump; 82. Aluminum or magnesium dosing component; 821. Aluminum or magnesium preparation tank; 822. Aluminum or magnesium dosing pump; 83. Sodium carbonate dosing component; 831. Sodium carbonate preparation tank; 832. Sodium carbonate dosing pump; 84. Flocculant dosing component; 841. Flocculant preparation tank; 842. Flocculant first dosing pump; 843. Flocculant second dosing pump; 85. Coagulant dosing component; 851. Coagulant preparation tank; 852. Coagulant first dosing pump; 853. Coagulant second dosing pump; 86. Acid dosing component; 861. Acid storage tank; 862. Acid dosing pump;

[0037] 101. Silicon removal sludge discharge pipeline; 102. Hardness removal sludge discharge pipeline; 103. Primary silicon removal water supply pipeline; 104. Primary hardness removal water supply pipeline; 105. Secondary silicon removal water supply pipeline; 106. Secondary hardness removal water supply pipeline; 107. Chemical preparation water inlet pipeline; 108. Silicon removal sludge return pipeline; 109. Hardness removal sludge return pipeline; 110. Wastewater treatment pipeline; 111. Silicon removal sludge replenishment pipeline; 112. Hardness removal sludge replenishment pipeline; 91. Silicon removal sludge discharge pump; 92. Silicon removal sludge return pump; 93. Hardness removal sludge discharge pump; 94. Hardness removal sludge return pump. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and beneficial technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining the present invention, not for limiting the present invention.

[0039] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0040] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0041] In an embodiment of the present invention, a secondary hardness and silicon removal wastewater treatment system 100 is provided, which is used to combine reagent addition and pipeline switching to test and obtain the best or better reaction sequence for silicon and hardness removal of target industrial wastewater.

[0042] like Figure 1As shown, the secondary hardness removal and silicon removal wastewater treatment system 100 includes: a primary silicon removal tank 10, a primary hardness removal tank 20, a secondary silicon removal high-density sedimentation tank 30, a secondary hardness removal high-density sedimentation tank 40, a silicon removal water production tank 50, a hardness removal water production tank 60, a multi-media filter 70, a chemical dosing system, a silicon removal sludge discharge pipeline 101, a hardness removal sludge discharge pipeline 102, a primary silicon removal water supply pipeline 103, a primary hardness removal water supply pipeline 104, a secondary silicon removal water supply pipeline 105, and a secondary hardness removal water supply pipeline 106.

[0043] Specifically, the primary desiliconization water delivery pipeline 103 is used to deliver the wastewater treated in the primary desiliconization tank 10 to the primary desiliconization tank 20 or the secondary desiliconization high-density sedimentation tank 30. The primary desiliconization water delivery pipeline 104 is used to deliver the wastewater treated in the primary desiliconization tank 20 to the primary desiliconization tank 10 or the secondary desiliconization high-density sedimentation tank 40. The secondary desiliconization water delivery pipeline 105 is used to deliver the produced water of the desiliconization water production tank 50 to the primary desiliconization tank 20 or the multi-media filter 70. The secondary desiliconization water delivery pipeline 106 is used to deliver the produced water of the desiliconization water production tank 60 to the primary desiliconization tank 10 or the multi-media filter 70.

[0044] The produced water after the reaction treatment in the secondary silicon removal high-density sedimentation tank 30 is transported to the silicon removal water production tank 50. The produced water after the reaction treatment in the secondary hardness removal high-density sedimentation tank 40 is transported to the hardness removal water production tank 60. The flow direction of the wastewater in the primary silicon removal tank 10, the primary hardness removal tank 20, the secondary silicon removal high-density sedimentation tank 30, the secondary hardness removal high-density sedimentation tank 40, the silicon removal water production tank 50, and the hardness removal water production tank 60 is switched through the primary / secondary silicon removal water delivery pipeline and the primary / secondary hardness removal water delivery pipeline, so that the optimal reaction sequence of the primary / secondary hardness removal and silicon removal can be tested, and the operation is simple.

[0045] For example, if the process of first-level silicon removal and then second-level silicon removal is carried out, and then first-level hardness removal and then second-level hardness removal is as follows: the wastewater to be treated passes through the first-level silicon removal tank 10, the first-level silicon removal water supply pipeline 103, the second-level silicon removal high-density sedimentation tank 30, the silicon removal water production tank 50, the second-level silicon removal water supply pipeline 105, the first-level hardness removal tank 20, the first-level hardness removal water supply pipeline 104, the second-level hardness removal high-density sedimentation tank 40, and the hardness removal water production tank 60 in sequence.

[0046] For another example, if the first-level hardness removal and then the first-level silicon removal are carried out, and then the second-level silicon removal and then the first-level hardness removal and the second-level hardness removal are carried out, the process is as follows: the wastewater to be treated passes through the first-level hardness removal tank 20, the first-level hardness removal water pipeline 104, the first-level silicon removal tank 10, the first-level silicon removal water pipeline 103, the second-level silicon removal high-density sedimentation tank 30, the silicon removal water production tank 50, the second-level silicon removal water pipeline 105, the first-level hardness removal tank 20, the first-level hardness removal water pipeline 104, the second-level hardness removal high-density sedimentation tank 40, and the hardness removal water production tank 60 in turn.

[0047] It should be noted that the primary silicon removal water pipeline 103, the primary hardness removal water pipeline 104, the secondary silicon removal water pipeline 105, and the secondary hardness removal water pipeline 106 are all provided with corresponding driving pumps to realize the flow of wastewater in the corresponding pipelines.

[0048] In an embodiment of the present invention, the secondary desiliconization high-density sedimentation tank 30 includes a desiliconization mixing tank 31, a desiliconization flocculation tank 32, and a desiliconization sedimentation tank 33, through which wastewater flows in sequence. The desiliconization flocculation tank 32 is provided with a guide tube, and the desiliconization mixing tank 31 extends into the bottom of the guide tube through a connecting pipe, so that the wastewater treated by the desiliconization mixing tank 31 passes through the connecting pipe and the guide tube in sequence and enters the desiliconization flocculation tank 32. Among them, the bell-mouth structure of the guide tube faces the bottom of the desiliconization flocculation tank 32. The primary desiliconization water supply pipeline 103 is connected to the desiliconization mixing tank 31, so the wastewater after the reaction of the primary desiliconization tank 10 can enter the desiliconization mixing tank 31 through the primary desiliconization water supply pipeline 103. The reaction flocculants in the desiliconization sedimentation tank 33 are separated from mud and water through a built-in inclined tube, and the sludge is settled in the built-in sludge hopper at the bottom.

[0049] Among them, the structures of the secondary hardness removal high-density sedimentation tank 30 and the secondary silicon removal high-density sedimentation tank 40 are almost the same, and the only difference is the type of added reagents and the connected pipes. Similarly, the secondary hardness removal high-density sedimentation tank 40 includes a hardness removal mixing tank 41, a hardness removal flocculation tank 42, and a hardness removal sedimentation tank 43. The hardness removal flocculation tank 42 is also provided with a guide tube, and the hardness removal mixing tank 41 also extends into the bottom of the corresponding guide tube through a connecting pipe, so that the wastewater treated by the hardness removal mixing tank 41 passes through the connecting pipe and the guide tube in turn into the hardness removal flocculation tank 42. The primary hardness removal water supply pipeline 104 is connected to the hardness removal mixing tank 41, and the wastewater after the reaction of the primary hardness removal tank 20 can enter the hardness removal mixing tank 41 through the primary hardness removal water supply pipeline 104. The reaction flocculants in the hardness removal sedimentation tank 43 are separated from mud and water through the built-in inclined tube, and the sludge is settled in the built-in sludge hopper at the bottom.

[0050] In an embodiment of the present invention, the reagent dosing system includes a lime milk or liquid alkali dosing component 81, an aluminum agent or magnesium agent dosing component 82, a sodium carbonate dosing component 83, a flocculant dosing component 84, a coagulant aid dosing component 85, and an acid dosing component 86.

[0051] Among them, the lime milk or liquid alkali dosing component 81 is used to add lime milk or liquid alkali solution to the primary silicon removal tank 10 and the primary hardness removal tank 20 respectively. Specifically, the lime milk or liquid alkali dosing component 81 includes a lime milk or liquid alkali preparation tank 811 for preparing lime milk or liquid alkali solution and a lime milk or liquid alkali first dosing pump 812 and a lime milk or liquid alkali second dosing pump 813 both connected to the lime milk or liquid alkali preparation tank 811. The lime milk or liquid alkali first dosing pump 812 is used to pump the lime milk or liquid alkali solution into the primary silicon removal tank 10. The lime milk or liquid alkali second dosing pump 813 is used to pump the lime milk or liquid alkali solution into the primary hardness removal tank 20. The "lime milk" described here is calcium hydroxide, and the "liquid alkali" is sodium hydroxide. The two are in a parallel relationship. You can choose one of them to add, or you can add them together. Among them, the functions of lime milk or liquid alkali solution include: neutralizing acidic wastewater and adjusting pH value; reacting with heavy metal ions (such as lead, cadmium, mercury, etc.) in wastewater to generate water-insoluble heavy metal hydroxide precipitates, thereby removing these harmful substances; due to its alkalinity, it can destroy the cell structure of bacteria and viruses; it can form colloids in water, and these colloids have strong adsorption capacity, which can adsorb suspended matter and colloidal particles in water, and form larger flocs through flocculation, which is convenient for subsequent precipitation and filtration.

[0052] The aluminum or magnesium agent dosing assembly 82 is used to add aluminum or magnesium agent solution to the primary desiliconization tank 10. Specifically, the aluminum or magnesium agent dosing assembly 82 includes an aluminum or magnesium agent preparation tank 821 for preparing the aluminum or magnesium agent solution and an aluminum or magnesium agent dosing pump 822 connected to the aluminum or magnesium agent preparation tank 821. The aluminum or magnesium agent dosing pump 822 is used to pump the aluminum or magnesium agent solution into the primary desiliconization tank 10. Among them, the functions of aluminum or magnesium agent (such as NaAlO2, sodium aluminate) solution include: it will produce alkalinity when hydrolyzed in water, so it can be used to adjust the pH value of wastewater; it will hydrolyze in water to form aluminum hydroxide colloids, which have strong adsorption capacity and can adsorb suspended matter, colloidal particles and some soluble organic matter in water to form flocs, which are easy to remove by precipitation or filtration; the aluminum hydroxide colloids generated by hydrolysis can react with heavy metal ions (such as lead, cadmium, chromium, etc.) in the wastewater to undergo complexation or precipitation reactions, thereby removing these harmful ions; it will react with phosphates in the wastewater to generate insoluble aluminum phosphate precipitates, thereby removing phosphorus from the sewage and preventing eutrophication of the water body; some pigments and organic matter in the wastewater can be removed through flocculation, thereby improving the clarity of the water.

[0053] The sodium carbonate dosing assembly 83 is used to add sodium carbonate solution to the primary de-hardening tank 20. Specifically, the sodium carbonate dosing assembly 83 includes a sodium carbonate preparation tank 831 for preparing the sodium carbonate solution and a sodium carbonate dosing pump 832 connected to the sodium carbonate preparation tank 831. The sodium carbonate dosing pump 832 is used to pump the sodium carbonate solution into the primary de-hardening tank 20. The sodium carbonate solution has the following functions: reacting with calcium ions (Ca 2+ ) and magnesium ions (Mg 2+ ) to generate insoluble calcium carbonate and magnesium carbonate precipitates, thereby reducing the hardness of water; neutralize acidic wastewater and increase the pH value of wastewater; react with metal ions (such as iron and aluminum) in wastewater to generate corresponding carbonate flocs, which help to capture and remove suspended matter and colloidal particles in water; in the flocculation process, it can improve the effect of flocculants, especially when iron salts or aluminum salts are used as flocculants, it can promote the formation of hydroxide flocs; promote the precipitation of heavy metal ions (such as lead, zinc, copper, etc.) by increasing the pH value to form insoluble carbonate precipitates, thereby removing these harmful ions; participate in redox reactions as an oxidant or reductant to help decompose or transform certain pollutants.

[0054] The flocculant dosing assembly 84 is used to respectively dosing flocculant solution into the secondary silicon removal high-density sedimentation tank 30 and the secondary hardness removal high-density sedimentation tank 40. Specifically, the flocculant dosing assembly 84 includes a flocculant preparation tank 841 for preparing the flocculant solution and a first flocculant dosing pump 842 and a second flocculant dosing pump 843 both connected to the flocculant preparation tank 841. The first flocculant dosing pump 842 is used to pump the flocculant solution into the silicon removal mixing tank 31. The second flocculant dosing pump 843 is used to pump the flocculant solution into the hardness removal mixing tank 41. Among them, the functions of flocculant (including but not limited to: Poly Aluminum Chloride, PAC, polyaluminum chloride; Polyferric Sulfate, PFS, polyferric sulfate; ferric chloride, etc.) solution include: it can be quickly hydrolyzed in water to form aluminum hydroxide colloids with positive charge. These colloids have strong adsorption capacity and can adsorb suspended matter, colloidal particles and some soluble organic matter in water. Through charge neutralization and bridging, larger flocs are formed, which are convenient for removal by precipitation or filtration; effectively remove pigments in wastewater and improve the water quality and transparency of effluent; react with heavy metal ions (such as lead, chromium, mercury, etc.) in wastewater to form insoluble precipitates, thereby removing these harmful ions; not only can it remove suspended matter and colloids in wastewater, but it can also remove soluble organic matter to a certain extent and improve the biodegradability of wastewater; it has certain oxidizability under specific conditions, can play a role of disinfection and oxidation, and help remove certain harmful microorganisms and organic pollutants in wastewater.

[0055] The coagulant dosing assembly 85 is used to respectively add a coagulant solution to the secondary silicon removal high-density sedimentation tank 30 and the secondary hardness removal high-density sedimentation tank 40. Specifically, the coagulant dosing assembly 85 includes a coagulant preparation tank 851 for configuring a coagulant solution, and a first coagulant dosing pump 852 and a second coagulant dosing pump 853 both connected to the coagulant preparation tank 851. The first coagulant dosing pump 852 is used to pump the coagulant solution into the bottom of the guide tube of the silicon removal mixing tank 31 and the silicon removal flocculation tank 32. The second coagulant dosing pump 853 is used to pump the coagulant solution into the bottom of the guide tube of the hardness removal mixing tank 41 and the hardness removal flocculation tank 42. Among them, the functions of coagulant (such as Polyacrylamide) solution include: as a highly efficient flocculation aid, it can aggregate suspended particles, colloids and certain soluble substances in the water to form larger flocs through the adsorption and bridging effect of its long-chain molecules, and these flocs are easier to separate from the water by sedimentation or flotation; it is usually used in combination with metal salt flocculants (such as PAC, aluminum sulfate, etc.), which can significantly improve the flocculation effect and reduce the amount of flocculants used; improve the sedimentation performance of sludge, make the sludge settle more quickly, thereby improving the clarification effect and sludge concentration efficiency; adsorb organic matter in the water, especially those that are difficult to biodegrade.

[0056] The acid dosing assembly 86 is used to respectively add sulfuric acid or hydrochloric acid to the desiliconization water production tank 50 and the dehardening water production tank 60. Specifically, the acid dosing assembly 86 includes an acid storage tank 861 and an acid dosing pump 862 connected to the acid storage tank 861. The acid dosing pump 862 is used to pump sulfuric acid or hydrochloric acid into the desiliconization water production tank 50 and the dehardening water production tank 60. Among them, sulfuric acid or hydrochloric acid is used to adjust the pH value in the produced water, kill bacteria and pathogens in the wastewater, etc.

[0057] In this embodiment, the reagent dosing system further includes a reagent preparation water inlet pipeline 107. The reagent preparation water inlet pipeline 107 is respectively connected to the lime milk or liquid caustic soda preparation tank 811, the aluminum or magnesium preparation tank 821, the sodium carbonate preparation tank 831, the flocculant preparation tank 841, and the coagulant aid preparation tank 851 to supply water to each preparation tank separately. The water source of the reagent preparation water inlet pipeline 107 can be municipal tap water, etc.

[0058] It should be noted that each dosing pump in the reagent dosing system is arranged in its own corresponding separate pipeline, so that each dosing pump can add reagents to each reaction position through the corresponding separate pipeline. Among them, each dosing pump of the coagulant dosing assembly 85 has two water outlets, so that the reagents can be added to the two reaction positions respectively.

[0059] In the embodiment of the present invention, the desiliconization sludge discharge pipeline 101 is used to discharge the sludge produced by the secondary desiliconization high-density sedimentation tank 30. The desiliconization sludge discharge pipeline 101 is provided with a desiliconization sludge discharge pump 91, and one end is connected to the bottom of the desiliconization sedimentation tank 33. The desiliconization sludge discharge pump 91 is used to discharge the sludge precipitated in the desiliconization sedimentation tank 33 through the desiliconization sludge discharge pipeline 101.

[0060] Furthermore, the system also includes a desiliconization sludge return pipeline 108. The desiliconization sludge return pipeline 108 is provided with a desiliconization sludge return pump 92, and one end is connected to the bottom of the desiliconization sedimentation tank 33, and the other end is connected to the desiliconization mixing tank 31. The desiliconization sludge return pump 92 is used to pump the sludge precipitated in the desiliconization sedimentation tank 33 back into the desiliconization mixing tank 31 through the desiliconization sludge return pipeline 108, thereby continuously improving the sludge concentration in the secondary desiliconization high-density sedimentation tank 30, and promoting the formation and precipitation of flocculants (playing a role similar to "seed crystals"). The desiliconization sludge return pump 92 can also be used to assist the desiliconization sludge pump 91 to discharge the sludge in the desiliconization sedimentation tank 33.

[0061] Accordingly, the hard-removal sludge discharge pipeline 102 is used to discharge the sludge produced by the secondary hard-removal high-density sedimentation tank 40. The hard-removal sludge discharge pipeline 102 is provided with a hard-removal sludge discharge pump 93, and one end is connected to the bottom of the hard-removal sedimentation tank 43. The hard-removal sludge discharge pump 93 is used to discharge the sludge precipitated in the hard-removal sedimentation tank 43 through the hard-removal sludge discharge pipeline 102.

[0062] Furthermore, the system also includes a hard sludge removal return pipeline 109. The hard sludge removal return pipeline 109 is provided with a hard sludge removal return pump 94, and one end is connected to the bottom of the hard sludge removal sedimentation tank 43, and the other end is connected to the hard sludge removal mixing tank 41. The hard sludge removal return pump 94 is used to pump the sludge precipitated in the hard sludge removal sedimentation tank 43 back into the hard sludge removal mixing tank 41 through the hard sludge removal return pipeline 109, thereby continuously improving the sludge concentration in the secondary hard sludge removal high-density sedimentation tank 40, and promoting the formation and precipitation of flocculants (playing a role similar to "seed crystals"). The hard sludge removal return pump 94 can also be used to assist the hard sludge removal pump 93 to discharge the sludge in the hard sludge removal sedimentation tank 43.

[0063] Furthermore, the silicon removal sludge discharge pipeline 101 is also connected to the silicon removal sludge replenishment pipeline 111. The rated power of the silicon removal sludge discharge pump 91 is greater than the rated power of the silicon removal sludge return pump 92. When the silicon removal sludge return pump 92 stops running, part of the sludge pumped out by the silicon removal sludge discharge pump 91 flows back to the silicon removal mixing tank 31 through the silicon removal sludge replenishment pipeline 111. At this time, the silicon removal sludge discharge pump 91 plays the role of sludge discharge and return at the same time, that is, when the silicon removal sludge return pump 92 is maintained, it plays a substitute role.

[0064] Similarly, the hard sludge removal pipeline 102 is also connected to the hard sludge removal supplementary pipeline 112. The rated power of the hard sludge removal pump 93 is greater than the rated power of the hard sludge removal return pump 94. When the hard sludge removal return pump 94 stops running, part of the sludge pumped out by the hard sludge removal pump 93 flows back to the hard sludge removal mixing tank 41 through the hard sludge removal supplementary pipeline 112. At this time, the hard sludge removal pump 93 plays the role of sludge discharge and return at the same time, that is, when the hard sludge removal return pump 94 is maintained, it plays a substitute role.

[0065] In the embodiment of the present invention, the multi-media filter 70 is used to filter the produced water of the secondary silicon removal high-density sedimentation tank 30 or the secondary hardness removal high-density sedimentation tank 40. The multi-media filter 70 can be a fiber ball filter, a scraper self-cleaning filter, or the like.

[0066] Furthermore, the system also includes a wastewater treatment pipeline 110. The wastewater treatment pipeline 110 is respectively connected to the primary silicon removal tank 10, the primary hardness removal tank 20, the secondary silicon removal high-density sedimentation tank 30, the secondary hardness removal high-density sedimentation tank 40, the silicon removal water production tank 50, the hardness removal water production tank 60, and the multi-media filter 70 to receive the wastewater produced by each of them and discharge it into the wastewater tank.

[0067] It should be noted that each pipeline described in the present invention is provided with a corresponding valve structure for controlling the on-off of the pipeline itself. For a pipeline with two or more water outlets, each water outlet is provided with a corresponding control valve, so the wastewater in the pipeline can be discharged from a certain water outlet by switching the on-off of these control valves.

[0068] In summary, the secondary hardness and silicon removal wastewater treatment system 100 provided by the present invention controls the primary / secondary silicon removal water supply pipeline and the primary / secondary hardness removal water supply pipeline through valves to switch the flow direction of wastewater in the primary silicon removal tank 10, the primary hardness removal tank 20, the secondary silicon removal high-density sedimentation tank 30, and the secondary hardness removal high-density sedimentation tank 40, and combines the chemical dosing system to add different chemicals to each tank, so as to test the best reaction sequence. The operation is simple, which can not only reduce the hardness and silicon content of the effluent water, but also reduce the treatment cost.

[0069] The present invention is not limited to what is described in the specification and implementation modes, and therefore additional advantages and modifications can be easily realized by those skilled in the art. Therefore, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details, representative devices, and illustrative examples shown and described herein.

Claims

1. A secondary hardness and silicon removal wastewater treatment system, characterized in that: include: Primary silicon removal tank, primary hardness removal tank, secondary silicon removal high-density sedimentation tank, secondary hardness removal high-density sedimentation tank, silicon removal water production tank, hardness removal water production tank, multi-media filter; A reagent dosing system, the reagent dosing system comprising a lime milk or liquid alkali dosing component, an aluminum agent or magnesium agent dosing component, a sodium carbonate dosing component, a flocculant dosing component, a coagulant aid dosing component, and an acid dosing component; A primary desiliconization water pipeline, the primary desiliconization water pipeline is used to transport the wastewater treated in the primary desiliconization tank to the primary hardness removal tank or the secondary desiliconization high-density sedimentation tank; A primary hardness removal water delivery pipeline, the primary hardness removal water delivery pipeline is used to transport the wastewater treated in the primary hardness removal tank to the primary silicon removal tank or the secondary hardness removal high-density sedimentation tank; A secondary desiliconization water pipeline, the secondary desiliconization water pipeline is used to transport the produced water of the desiliconization water production tank to the primary hardness removal tank or the multi-media filter; A secondary de-hardening water delivery pipeline, the secondary de-hardening water delivery pipeline is used to deliver the produced water from the de-hardening water production tank to the primary desiliconization tank or the multi-media filter; The lime milk or liquid alkali adding component is used to add lime milk or liquid alkali solution to the primary silicon removal tank and the primary hardness removal tank respectively; the aluminum agent or magnesium agent adding component is used to add aluminum agent or magnesium agent solution to the primary silicon removal tank; the sodium carbonate adding component is used to add sodium carbonate solution to the primary hardness removal tank; the flocculant adding component is used to add flocculant solution to the secondary silicon removal high-density sedimentation tank and the secondary hardness removal high-density sedimentation tank respectively, and the coagulant adding component is used to add coagulant aid solution to the secondary silicon removal high-density sedimentation tank and the secondary hardness removal high-density sedimentation tank respectively; the acid adding component is used to add sulfuric acid or hydrochloric acid to the silicon removal water production tank and the hardness removal water production tank respectively; A desiliconization sludge discharge pipeline, which is used to discharge the sludge produced by the secondary desiliconization high-density sedimentation tank; A hard-sludge removal pipeline, which is used to discharge the sludge produced by the secondary hard-sludge removal high-density sedimentation tank; The multi-media filter is used to filter the produced water of the secondary silicon removal high-density sedimentation tank or the secondary hardness removal high-density sedimentation tank.

2. The secondary hardness and silicon removal wastewater treatment system according to claim 1, characterized in that: It also includes a wastewater treatment pipeline, which is respectively connected to the primary silicon removal tank, the primary hardness removal tank, the secondary silicon removal high-density sedimentation tank, the secondary hardness removal high-density sedimentation tank, the silicon removal water production tank, the hardness removal water production tank, and the multi-media filter to receive the wastewater produced by each of them and discharge it into the wastewater tank.

3. The secondary hardness and silicon removal wastewater treatment system according to claim 1, characterized in that: The secondary silicon removal high-density sedimentation tank includes a silicon removal mixing tank, a silicon removal flocculation tank, and a silicon removal sedimentation tank; the silicon removal flocculation tank is provided with a guide tube, and the silicon removal mixing tank extends into the bottom of the guide tube through a connecting pipe; the primary silicon removal water supply pipeline is connected to the silicon removal mixing tank; the secondary hardness removal high-density sedimentation tank includes a hardness removal mixing tank, a hardness removal flocculation tank, and a hardness removal sedimentation tank; the hardness removal flocculation tank is also provided with a guide tube, and the hardness removal mixing tank also extends into the bottom of the corresponding guide tube through a connecting pipe; the primary hardness removal water supply pipeline is connected to the hardness removal mixing tank.

4. The secondary hardness and silicon removal wastewater treatment system according to claim 3, characterized in that: The silicon removal sludge discharge pipeline is provided with a silicon removal sludge discharge pump, and one end of the silicon removal sludge discharge pipeline is connected to the bottom of the silicon removal sedimentation tank, and the silicon removal sludge discharge pump is used to discharge the sludge precipitated in the silicon removal sedimentation tank through the silicon removal sludge discharge pipeline; the hardness removal sludge discharge pipeline is provided with a hardness removal sludge discharge pump, and one end of the hardness removal sludge discharge pipeline is connected to the bottom of the hardness removal sedimentation tank, and the hardness removal sludge discharge pump is used to discharge the sludge precipitated in the hardness removal sedimentation tank through the hardness removal sludge discharge pipeline.

5. The secondary hardness and silicon removal wastewater treatment system according to claim 4, characterized in that: It also includes a silicon removal sludge return pipeline and a hardness removal sludge return pipeline; the silicon removal sludge return pipeline is provided with a silicon removal sludge return pump, and one end is connected to the bottom of the silicon removal sedimentation tank, and the other end is connected to the silicon removal mixing tank; the silicon removal sludge return pump is used to pump the sludge precipitated in the silicon removal sedimentation tank through the silicon removal sludge return pipeline and return it to the silicon removal mixing tank, or to assist the silicon removal sludge pump to discharge the sludge in the silicon removal sedimentation tank; the hardness removal sludge return pipeline is provided with a hardness removal sludge return pump, and one end is connected to the bottom of the hardness removal sedimentation tank, and the other end is connected to the hardness removal mixing tank; the hardness removal sludge return pump is used to pump the sludge precipitated in the hardness removal sedimentation tank through the hardness removal sludge return pipeline and return it to the hardness removal mixing tank, or to assist the hardness removal sludge pump to discharge the sludge in the hardness removal sedimentation tank.

6. The secondary hardness and silicon removal wastewater treatment system according to claim 5, characterized in that: The silicon removal sludge discharge pipeline is also connected to a silicon removal sludge replenishing pipeline, and the rated power of the silicon removal sludge discharge pump is greater than the rated power of the silicon removal sludge return pump; when the silicon removal sludge return pump stops running, part of the sludge pumped out by the silicon removal sludge pump flows back to the silicon removal mixing tank through the silicon removal sludge replenishing pipeline; the hard sludge removal discharge pipeline is also connected to a hard sludge removal replenishing pipeline, and the rated power of the hard sludge removal pump is greater than the rated power of the hard sludge removal return pump; when the hard sludge removal return pump stops running, part of the sludge pumped out by the hard sludge removal pump flows back to the hard removal mixing tank through the hard sludge replenishing pipeline.

7. The secondary hardness and silicon removal wastewater treatment system according to claim 3, characterized in that: The lime milk or liquid alkali dosing component comprises a lime milk or liquid alkali preparation tank for preparing lime milk or liquid alkali solution, and a first lime milk or liquid alkali dosing pump and a second lime milk or liquid alkali dosing pump both of which are connected to the lime milk or liquid alkali preparation tank; the first lime milk or liquid alkali dosing pump is used to pump the lime milk or liquid alkali solution into the primary desiliconization tank, and the second lime milk or liquid alkali dosing pump is used to pump the lime milk or liquid alkali solution into the primary dehardness removal tank; The aluminum or magnesium agent dosing assembly includes an aluminum or magnesium agent preparation tank for preparing an aluminum or magnesium agent solution and an aluminum or magnesium agent dosing pump connected to the aluminum or magnesium agent preparation tank; the aluminum or magnesium agent dosing pump is used to pump the aluminum or magnesium agent solution into the primary desiliconization tank; The sodium carbonate dosing assembly includes a sodium carbonate preparation tank for preparing a sodium carbonate solution and a sodium carbonate dosing pump connected to the sodium carbonate preparation tank; the sodium carbonate dosing pump is used to pump the sodium carbonate solution into the primary hardness removal tank; The flocculant dosing component includes a flocculant preparation tank for preparing a flocculant solution, and a first flocculant dosing pump and a second flocculant dosing pump both of which are connected to the flocculant preparation tank; the first flocculant dosing pump is used to pump the flocculant solution into the silicon removal mixing tank, and the second flocculant dosing pump is used to pump the flocculant solution into the hardness removal mixing tank; The coagulant dosing assembly includes a coagulant preparation tank for preparing a coagulant solution, and a first coagulant dosing pump and a second coagulant dosing pump both of which are connected to the coagulant preparation tank; the first coagulant dosing pump is used to pump the coagulant solution into the bottom of the guide tube of the silicon removal mixing tank and the silicon removal flocculation tank, and the second coagulant dosing pump is used to pump the coagulant solution into the bottom of the guide tube of the hardness removal mixing tank and the hardness removal flocculation tank; The acid dosing assembly comprises an acid storage tank and an acid dosing pump connected to the acid storage tank, and the acid dosing pump is used to pump sulfuric acid or hydrochloric acid into the silicon removal water production tank and the hardness removal water production tank respectively.

8. The secondary hardness and silicon removal wastewater treatment system according to claim 7, characterized in that: The reagent dosing system also includes a reagent preparation water inlet pipeline; the reagent preparation water inlet pipeline is respectively connected to the lime milk or liquid alkali preparation tank, the aluminum or magnesium agent preparation tank, the sodium carbonate preparation tank, the flocculant preparation tank, and the coagulant aid preparation tank to supply water to each preparation tank separately.

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