Sewage treatment process and device

Abstract

The invention relates to the technical field of sewage treatment, in particular to a sewage treatment process and a sewage treatment device, and particularly relates to a nucleation granulation-ozonization integrated water treatment process and a nucleation granulation-ozonization integrated water treatment device for synchronously removing metal ions and organic matters in sewage. When the sewage treatment device provided by the invention is used for sewage treatment, metal ions and organic matters in sewage can be effectively removed, the treatment efficiency is high, the effect is stable, chemical sludge is not generated, a chemical sludge treatment device is omitted, and the device is small in occupied area and low in cost and has important significance in the field of sewage treatment.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, in particular to a sewage treatment process and device, and specifically to a nuclear crystal granulation-ozonation integrated water treatment process and device for simultaneously removing metal ions and organic matter in sewage. Background Art

[0002] Chemical precipitation is a common treatment method for removing metal ions from wastewater. It uses alkaline agents to react with metal ions to form precipitates, which are then removed by solid-liquid separation. However, conventional solid-liquid separation uses physical sedimentation, which usually requires a long sedimentation time and a large floor space, and produces a large amount of chemical sludge. In addition, traditional chemical precipitation has limited effect on the removal of organic matter in water.

[0003] Therefore, a sewage treatment process and device are proposed for the efficient removal of metal ions and organic matter in sewage. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a sewage treatment process and device, in particular, a nuclear crystal granulation-ozonation integrated water treatment process and device for simultaneously removing metal ions and organic matter in sewage. The sewage treatment device provided by the present invention is used for sewage treatment, which can effectively remove metal ions and organic matter in sewage, has high treatment efficiency and stable effect, and does not produce chemical sludge, eliminating the need for chemical sludge treatment equipment. The device occupies a small area and has low cost, which is of great significance in the field of sewage treatment.

[0005] In a first aspect, the present invention provides a sewage treatment device, the treatment device comprising a sewage tank, a seed tank, a first reagent tank, a reaction tank, an ozone generator, a scum collection tank and a clean water tank;

[0006] The reaction tank comprises an inner cylinder, an outer cylinder, an aeration device and an exhaust pipe; the exhaust pipe is arranged below the outer cylinder, the inner cylinder is arranged inside the outer cylinder, the top of the inner cylinder is an open structure, the bottom of the inner cylinder is connected to the bottom of the outer cylinder, and the bottoms of the inner cylinder and the outer cylinder are both provided with an aeration device;

[0007] The sewage tank, the seed box and the first reagent box are connected to the inner cylinder through pipelines respectively;

[0008] The ozone generating device is connected to the aeration device via a pipeline;

[0009] The scum collecting box and the clean water tank are connected to the outer cylinder through pipelines respectively.

[0010] The sewage treatment device provided by the present invention is a nuclear crystal granulation-ozonation integrated water treatment device. The sewage treatment device provided by the present invention is used for sewage treatment, which can effectively remove metal ions and organic matter in sewage, has high treatment efficiency and stable effect, and does not produce chemical sludge, eliminating the need for a chemical sludge treatment device, and the device occupies a small area and has low cost. Specifically:

[0011] The sewage treatment device provided by the present invention adds crystal seeds into the inner cylinder for nucleus crystal granulation, which promotes the dense growth of precipitates on the surface of the crystal seeds to achieve floc densification, thereby efficiently removing metal ions and avoiding the generation of chemical sludge. At the same time, aeration devices are arranged at the bottom of the inner cylinder and the outer cylinder to expose ozone. On the one hand, the growth of crystals is regulated by physical action, and on the other hand, ozone reacts with the first agent to act on organic matter to strengthen the removal of organic matter, thereby achieving efficient removal of metal ions and organic matter in sewage, and can save the amount of medicine required for the ozonation process, saving costs.

[0012] As a preferred technical solution of the present invention, the inner cylinder and the outer cylinder are coaxially arranged.

[0013] As a preferred technical solution of the present invention, the diameter of the upper end of the inner cylinder is larger than the diameter of the lower end. This arrangement can ensure that the crystal seeds and precipitates in the inner cylinder are not washed into the outer cylinder.

[0014] As a preferred technical solution of the present invention, the sewage tank, seed box and first reagent box are respectively connected to the bottom of the inner tube through pipes. This arrangement can ensure that the sewage can fully contact and react with the seed crystals and the first reagent after entering the bottom of the inner tube.

[0015] As a preferred technical solution of the present invention, the scum collection box and the clean water tank are respectively connected to the upper side of the outer cylinder through pipelines.

[0016] As a preferred technical solution of the present invention, the connection position of the scum collection box and the outer cylinder is higher than the connection position of the clean water tank and the outer cylinder, that is, the position of the scum discharge port on the outer cylinder is higher than the position of the water outlet, so as to remove the scum generated during the ozone flotation process and ensure that the outlet water and the scum are completely separated.

[0017] As a preferred technical solution of the present invention, the processing device also includes a second medicine box, and the second medicine box is connected to the outer cylinder through a pipeline.

[0018] As a preferred technical solution of the present invention, the second medicine box is connected to the lower side of the outer tube through a pipeline.

[0019] As a preferred technical solution of the present invention, the second agent box contains a second agent, and the second agent is selected from an oxidant, a coagulant or a catalyst, which can synergistically act with ozone on organic matter to further enhance the removal effect of organic matter.

[0020] As a preferred technical solution of the present invention, the oxidant is selected from any one or more of ozone, hydrogen peroxide or peracetic acid, and the dosage of the oxidant is 200-2000 mg / L, for example, 200 mg / L, 500 mg / L, 1000 mg / L, 1500 mg / L, 2000 mg / L, etc.

[0021] As a preferred technical solution of the present invention, the coagulant is selected from any one or more of aluminum chloride, ferric chloride, polyaluminum chloride or polyferric chloride, and the dosage of the coagulant is 200-1000 mg / L, for example, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, 1000 mg / L, etc.

[0022] As a preferred technical solution of the present invention, the catalyst is selected from any one or more of ceramsite, activated carbon or activated alumina, and the dosage of the catalyst is 100-500 mg / L, for example, 100 mg / L, 200 mg / L, 300 mg / L, 400 mg / L, 500 mg / L, etc.

[0023] As a preferred technical solution of the present invention, the processing device also includes a crystal collection box, which is connected to the bottom of the inner cylinder through a pipeline, and is used to regularly collect grown crystal seeds deposited at the bottom of the inner cylinder, and replenish new crystal seeds from the crystal seed box. It can be understood that a valve is set at the bottom of the inner cylinder. When the crystal seeds need to be discharged, the valve is opened, and the valve is closed during the operation of the device.

[0024] As a preferred technical solution of the present invention, the processing device also includes a tail gas processing system, and the tail gas processing system is connected to the top of the reaction tank through a pipeline.

[0025] As a preferred technical solution of the present invention, the seed box is provided with seeds, and the seeds include natural ore and / or synthetic material.

[0026] The natural minerals include garnet, dolomite, brucite, quartz sand and the like, and the synthetic materials include resin, oxide, metal particles and the like.

[0027] As a preferred technical solution of the present invention, the first medicine box contains a first medicine, and the first medicine is an alkaline medicine, preferably any one or more of sodium hydroxide, sodium carbonate or calcium hydroxide.

[0028] The metal ions in the sewage can react with the alkaline agent to generate precipitation attached to the surface of the seed crystal, and form dense crystals under the regulation of hydraulics and ozone gas. After growing to a certain size, they sink to the bottom of the inner tube and are removed regularly, thereby achieving the removal of metal ions.

[0029] In a second aspect, the present invention provides a sewage treatment process, which is performed using the sewage treatment device described in the first aspect, and the steps are as follows:

[0030] The sewage enters the bottom of the inner cylinder of the reaction tank from the sewage tank, and the seeds and the first reagent are added from the seed box and the first reagent box respectively. At the same time, the ozone generator is turned on, and ozone is exposed by the aeration device. Then the sewage enters the outer cylinder from the top of the inner cylinder. After staying for a period of time, the scum is discharged into the scum collection box, and the effluent is discharged into the clean water tank.

[0031] The sewage treatment process of the present invention is carried out using the sewage treatment device described in the first aspect. The seed crystals are suspended by hydraulic action in the reaction tank, the metal ions in the water and the first agent form insoluble substances through chemical action and precipitate on the surface of the seed crystals, and the organic matter is degraded by the action of ozone, thereby achieving efficient removal of metal ions and organic matter in the sewage, and the sewage treatment effect is efficient and stable.

[0032] As a preferred technical solution of the present invention, the steps of the treatment process are as follows: sewage enters the bottom of the inner cylinder of the reaction tank from the sewage tank, and seeds and the first reagent are added from the seed box and the first reagent box respectively, and the ozone generator is turned on at the same time, and ozone is exposed by the aeration device. Then the sewage enters the outer cylinder from the top of the inner cylinder, and the second reagent is added from the second reagent box. After staying for a period of time, the scum is discharged into the scum collection box, and the effluent is discharged into the clean water tank.

[0033] As a preferred technical solution of the present invention, the rising flow rate of the sewage in the inner tube is 50-120m / h, for example, 50m / h, 80m / h, 100m / h, 120m / h, etc.

[0034] As a preferred technical solution of the present invention, the hydraulic retention time of the sewage in the outer cylinder is 10-120 min, for example, 10 min, 30 min, 60 min, 90 min, 120 min, etc.

[0035] As a preferred technical solution of the present invention, the amount of the seed crystal is 0.1-0.5 mg seed crystal / mg metal ion, that is, the amount of seed crystal per mg metal ion is 0.1-0.5 mg, such as 0.1 mg, 0.2 mg, 0.3 mg, 0.4 mg, 0.5 mg, etc.

[0036] As a preferred technical solution of the present invention, the aeration rate of ozone is 200-2000 mg / min, for example, 200 mg / min, 500 mg / min, 1000 mg / min, 1500 mg / min, 2000 mg / min, etc.

[0037] As a preferred technical solution of the present invention, the dosage of the first agent is 100-1000 mg / L, that is, the dosage of the first agent per liter of water is 100-1000 mg / L, for example, 100 mg / L, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, 1000 mg / L, etc.

[0038] The technical solution provided by the embodiment of the present invention has the following advantages compared with the prior art:

[0039] The sewage treatment device provided by the present invention can effectively remove metal ions and organic matter in sewage by treating sewage, has high treatment efficiency and stable effect, and does not produce chemical sludge, thereby eliminating the need for chemical sludge treatment equipment. The device occupies a small area and has low cost, which is of great significance in the field of sewage treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0042] Figure 1 The sewage treatment device described in Example 4 of the present invention;

[0043] Among them, 1-wastewater tank; 2-seed box; 3-first reagent box; 4-reaction tank; 5-ozone generator; 6-scum collection box; 7-clean water tank; 8-second reagent box; 9-crystal collection box; 10-exhaust treatment device;

[0044] 41 - inner tube; 42 - outer tube; 43 - aeration device; 44 - drain pipe. DETAILED DESCRIPTION

[0045] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the scheme of the present invention will be further described below. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0046] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0047] Example 1

[0048] This embodiment provides a sewage treatment device and a sewage treatment process, wherein the sewage treatment device includes a sewage tank 1, a seed box 2, a first reagent box 3, a reaction tank 4, an ozone generator 5, a scum collection box 6, a clean water tank 7, a crystal collection box 9 and an exhaust gas treatment system 10;

[0049] The reaction tank 4 includes an inner cylinder 41, an outer cylinder 42, an aeration device 43 and an exhaust pipe 44; the exhaust pipe 44 is arranged below the outer cylinder 42 and is used for the maintenance of the treatment device. The inner cylinder 41 is arranged inside the outer cylinder 42, and the inner cylinder 41 and the outer cylinder 42 are arranged coaxially. The height of the inner cylinder 41 is smaller than that of the outer cylinder 42. The top of the inner cylinder 41 is an open structure. The bottom of the inner cylinder 41 is connected to the bottom of the outer cylinder 42. The bottom of the inner cylinder 41 and the bottom of the outer cylinder 42 are both provided with an aeration device 43.

[0050] The sewage tank 1, the seed box 2 and the first reagent box 3 are respectively connected to the bottom of the inner cylinder 41 through pipes;

[0051] The ozone generating device 5 is connected to the aeration device 43 via a pipeline;

[0052] The scum collecting box 6 and the clean water tank 7 are connected to the upper side of the outer cylinder 42 through pipelines respectively;

[0053] The crystal collection box 9 is connected to the bottom of the inner cylinder 41 through a pipeline;

[0054] The tail gas treatment system 10 is connected to the top of the reaction tank 4 through a pipeline;

[0055] The seed box 2 is provided with seed dolomite, and the first reagent box 3 contains sodium carbonate;

[0056] The sewage treatment process is carried out using the above-mentioned sewage treatment device, and specifically comprises the following steps:

[0057] Before sewage enters the device, crystal seeds are introduced into the inner tube 41 from the crystal seed box 2. The crystal seeds stop when they reach a certain height. Then the raw sewage enters the bottom of the inner tube 41 from the sewage tank 1. At the same time, the first agent (sodium carbonate) enters the inner tube 41 from the first agent box 3. The dosage of the first agent is 1000 mg / L water. The ozone generator 5 is turned on, and ozone is introduced through the aeration device 43. The ozone aeration volume is 1000 mg / min. The rising flow rate of sewage in the inner tube 41 is controlled to be 80 m / h. The metal ions in the water react with the alkaline agent to generate precipitates attached to the surface of the crystal seeds, and form dense crystals under the control of hydraulic and ozone gas. When the sewage flows to the top of the inner tube 41, the flow rate decreases due to the increase in the pipe diameter. Insoluble substances are more likely to settle and will not be carried out of the inner tube 41 by the water flow. At the same time, due to the effect of ozone, organic matter in the water can be oxidized and modified. Then the sewage enters the outer cylinder 42 from the top of the inner cylinder 41, and the hydraulic retention time of the sewage in the outer cylinder 42 is controlled to be 60 minutes. Ozone is continuously introduced into the outer cylinder 42 to strengthen the oxidation removal of organic matter. After nuclear crystal granulation and ozonation treatment, the metal ions and organic matter in the water are effectively removed, and the clean water is discharged from the top of the reaction tank 4 into the clean water tank 7. If scum is generated, the scum is discharged into the scum collection box 6. As the crystals in the inner cylinder 41 continue to grow, the grown crystals are regularly discharged into the crystal collection box 9, and new crystal seeds are added from the seed box 2. It was found that the calcium ion content in the clean water dropped from 1000mg / L to 36mg / L, and the organic matter content dropped from 500mgCOD / L to 37mgCOD / L.

[0058] Example 2

[0059] This embodiment provides a sewage treatment device and a sewage treatment process, the sewage treatment device is the same as that in embodiment 1, the sewage treatment process is the same as that in embodiment 1, and the difference from embodiment 1 is that in this embodiment, the rising velocity of sewage in the inner cylinder 41 is 120m / h, and the hydraulic retention time of sewage in the outer cylinder 42 is 120min. It is found that the calcium ion content in the clear water is reduced from 1000mg / L to 152mg / L, and the organic matter content is reduced from 500mgCOD / L to 15mgCOD / L.

[0060] Example 3

[0061] This embodiment provides a sewage treatment device and a sewage treatment process, the sewage treatment device is the same as that in embodiment 1, the sewage treatment process is the same as that in embodiment 1, and the difference from embodiment 1 is that in this embodiment, the rising velocity of the sewage in the inner cylinder 41 is 50m / h, and the hydraulic retention time of the sewage in the outer cylinder 42 is 10min. It is found that the calcium ion content in the clear water is reduced from 1000mg / L to 22mg / L, and the organic matter content is reduced from 500mgCOD / L to 215mgCOD / L.

[0062] Example 4

[0063] This embodiment provides a sewage treatment device and a sewage treatment process. The sewage treatment device is the same as that in Embodiment 1, except that the sewage treatment device in this embodiment further includes a second reagent box 8, the second reagent box contains polyaluminum chloride, and the second reagent box 8 is connected to the outer cylinder 42 through a pipeline. Figure 1 shown.

[0064] The sewage treatment process is the same as that in Example 1, except that in this embodiment, when the sewage enters the outer cylinder 42 from the top of the inner cylinder 41, polyaluminium chloride is added to the outer cylinder 42 through the second reagent box 8, and the addition amount is 600mg / L, so as to further improve the removal effect of organic matter. It is found that the calcium ion content in the clean water is reduced from 1000mg / L to 12mg / L, and the organic matter content is reduced from 500mgCOD / L to 35mgCOD / L.

[0065] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0066] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments described herein, but should conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sewage treatment device, characterized in that: The treatment device comprises a sewage tank (1), a seed tank (2), a first reagent tank (3), a reaction tank (4), an ozone generating device (5), a scum collecting tank (6) and a clean water tank (7); The reaction tank (4) comprises an inner cylinder (41), an outer cylinder (42), an aeration device (43) and an exhaust pipe (44); the exhaust pipe (44) is arranged below the outer cylinder (42); the inner cylinder (41) is arranged inside the outer cylinder (42); the top of the inner cylinder (41) is an open structure; the bottom of the inner cylinder (41) is connected to the bottom of the outer cylinder (42); and the aeration device (43) is arranged at the bottom of both the inner cylinder (41) and the outer cylinder (42); The sewage tank (1), the seed box (2) and the first reagent box (3) are respectively connected to the inner cylinder (41) through pipelines; The ozone generating device (5) is connected to the aeration device (43) via a pipeline; The scum collection box (6) and the clean water box (7) are respectively connected to the outer cylinder (42) through pipelines.

2. The sewage treatment device according to claim 1, characterized in that: The inner cylinder (41) and the outer cylinder (42) are coaxially arranged; And / or, the diameter of the upper end of the inner cylinder (41) is greater than the diameter of the lower end.

3. The sewage treatment device according to claim 1 or 2, characterized in that: The sewage tank (1), the seed box (2) and the first reagent box (3) are respectively connected to the bottom of the inner cylinder (41) through pipelines.

4. The sewage treatment device according to any one of claims 1 to 3, characterized in that: The scum collecting box (6) and the clean water box (7) are respectively connected to the upper side of the outer cylinder (42) through pipelines; Preferably, the connection position between the scum collection box (6) and the outer cylinder (42) is higher than the connection position between the clean water tank (7) and the outer cylinder (42).

5. The sewage treatment device according to any one of claims 1 to 4, characterized in that: The processing device further comprises a second medicine box (8), wherein the second medicine box (8) is connected to the outer cylinder (42) via a pipeline; Preferably, the second reagent box (8) contains a second reagent, and the second reagent is selected from an oxidant, a coagulant or a catalyst.

6. The sewage treatment device according to any one of claims 1 to 5, characterized in that: The processing device also includes a crystal collection box (9), and the crystal collection box (9) is connected to the bottom of the inner cylinder (41) through a pipeline.

7. The sewage treatment device according to any one of claims 1 to 6, characterized in that: The processing device further comprises a tail gas processing system (10), and the tail gas processing system (10) is connected to the top of the reaction tank (4) via a pipeline.

8. The sewage treatment device according to any one of claims 1 to 7, characterized in that: The seed box (2) is provided with seed crystals, and the seed crystals include natural ore and / or synthetic material; And / or, the first medicine box (3) contains a first medicine, and the first medicine is selected from any one or more of sodium hydroxide, sodium carbonate or calcium hydroxide.

9. A sewage treatment process, characterized in that: The sewage treatment process is carried out using the sewage treatment device according to any one of claims 1 to 8, and the steps are as follows: Sewage enters the bottom of the inner cylinder (41) of the reaction tank (4) from the sewage tank (1), and crystal seeds and the first reagent are added from the crystal seed box (2) and the first reagent box (3) respectively. At the same time, the ozone generator (5) is turned on, and ozone is introduced from the aeration device (43). Subsequently, the sewage enters the outer cylinder (42) from the top of the inner cylinder (41). After staying for a period of time, the scum is discharged into the scum collection box (6), and the effluent is discharged into the clean water tank (7).

10. The sewage treatment process according to claim 9, characterized in that: The rising flow rate of the sewage in the inner tube (41) is 50-120 m / h; And / or, the hydraulic retention time of the sewage in the outer cylinder (42) is 10-120 minutes.

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