A wastewater treatment process and apparatus

Abstract

The present application relates to wastewater treatment technical field, especially to a kind of wastewater treatment process and device.The wastewater treatment process includes the following steps: wastewater is sequentially flowed through crystallization zone, oxidation zone and granulation zone and is treated, and clean water is obtained;Wherein, the wastewater contains metal ions and organic matter;The crystallization zone carries out ion crystallization and forms ion crystal, the oxidation zone carries out organic matter oxidation modification, modified organic matter and ion crystal are complexed and form polymer, and the granulation zone makes the polymer form granulation body.The wastewater treatment process provided by the present application can realize the effective removal of metal ions and organic matter in wastewater, strengthen the treatment effect, improve the solid-liquid separation efficiency, shorten the process flow, no chemical sludge is produced, and the device occupies small area, which has important significance in the field of wastewater treatment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, in particular to a wastewater treatment process and device. BACKGROUND

[0002] With the development of industrialization, more and more complex organic wastewater is generated in the industrial production process. If these organic wastewater is not effectively treated, a large amount of organic pollutants will pollute the water body, destroy the balance of the aquatic ecosystem, and cause adverse effects such as cytotoxicity and genetic toxicity. Organic pollution has been an important threat to environmental protection and public health. Traditional organic control methods include physical adsorption, chemical oxidation, and biological degradation, which can remove some organic pollutants to some extent, but still face some limitations and challenges. For example, chemical oxidation methods may use strong oxidants such as permanganate and hydrogen peroxide, which have high cost, danger and complexity of operation. In addition, the biological degradation method has low degradation efficiency for some organic pollutants and requires a long time for treatment and a large area for occupation. The physical adsorption method usually requires a large amount of adsorbent, and the subsequent regeneration and treatment process may cause secondary pollution.

[0003] In addition, there are often a large amount of dissolved ions such as calcium, magnesium and silicon in wastewater, which will deposit and form scale in industrial equipment, causing wear, blockage and failure of the equipment, and increasing maintenance and operating costs. In some industrial production processes, water hardness has an important influence on product quality. Therefore, the effective removal of scale-forming ions is also of great significance to industrial production. Common ion control methods include chemical precipitation and ion exchange, which produces a large amount of chemical sludge, and ion exchange is costly, and the regenerated concentrated water is also difficult to handle.

[0004] Therefore, it is of great significance to provide a treatment process and device that can effectively remove organic matter and metal ions in wastewater. SUMMARY

[0005] To solve the above technical problems, the present application provides a wastewater treatment process and device. The wastewater treatment process provided by the present application can effectively remove metal ions and organic matter in wastewater, strengthen the treatment effect, improve the solid-liquid separation efficiency, shorten the process flow, and produce no chemical sludge. The device has a small footprint and is of great significance in the field of wastewater treatment.

[0006] In a first aspect, the present application provides a wastewater treatment process, comprising the following steps: passing wastewater through a crystallization zone, an oxidation zone and a granulation zone in sequence for treatment to obtain clean water.

[0007] The wastewater contains metal ions and organic matter.

[0008] The crystallization zone forms ion crystals by ion crystallization, the oxidation zone modifies organic matters by oxidation, modified organic matters are complexed with ion crystals to form aggregates, and the granulation zone forms granules from the aggregates.

[0009] The wastewater treatment process provided by the application can effectively remove metal ions and organic matters in wastewater, strengthen treatment effect, improve solid-liquid separation efficiency, shorten process flow, and does not produce chemical sludge.

[0010] As a preferred technical solution of the application, the wastewater enters from the bottom of the crystallization zone, overflows from the top of the crystallization zone to the oxidation zone, and flows from the bottom of the oxidation zone to the granulation zone.

[0011] The wastewater flow direction is set as the above case, which can strengthen the wastewater treatment effect and effectively reduce the floor area of the device.

[0012] As a preferred technical solution of the application, the crystallization zone is provided with an ion crystallization inducer, and the presence of the ion crystallization inducer can induce metal ion crystallization.

[0013] As a preferred technical solution of the application, the molar ratio of the ion crystallization inducer to the metal ion is 0.8-1.5:1, for example, 0.8:1, 1.0:1, 1.2:1, 1.4:1, 1.5:1, etc.

[0014] As a preferred technical solution of the application, the metal ion inducer is selected from inorganic salts, such as carbonates, sulfates, silicates, etc., which can produce insoluble precipitates with metal ions.

[0015] As a preferred technical solution of the application, the oxidation zone is exposed to ozone gas, and the organic matters in the wastewater can be modified by oxidation under the oxidation of the ozone gas, and then the modified organic matters can be complexed with ion crystals to form aggregates.

[0016] As a preferred technical solution of the application, the exposure amount of the ozone gas is 0.1-2mg / (mg COD), for example, 0.1mg / (mg COD), 0.5mg / (mg COD), 1mg / (mg COD), 1.5mg / (mg COD), 2mg / (mg COD).

[0017] As a preferred technical solution of the application, the granulation zone is provided with glass beads. The glass beads can induce aggregates to form dense granules.

[0018] As a preferred technical solution of the application, the particle size of the glass beads is 1-5mm, for example, 1mm, 2mm, 3mm, 4mm, 5mm, etc.

[0019] As a preferred technical solution of the present application, the filling height of the glass beads is 5-20% of the total height of the granulation zone, for example 5%, 10%, 15%, 20%, etc.

[0020] As a preferred technical solution of the present application, the hydraulic retention time of the crystallization zone is 2-5 min, for example 2 min, 3 min, 4 min, 5 min, etc.

[0021] As a preferred technical solution of the present application, the hydraulic retention time of the oxidation zone is 10-60 min, for example 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, etc.

[0022] As a preferred technical solution of the present application, the hydraulic retention time of the granulation zone is 5-40 min, for example 5 min, 10 min, 20 min, 30 min, 40 min, etc.

[0023] When the hydraulic retention time of the crystallization zone, the oxidation zone and the granulation zone is within the above range, the reaction of each step can be more complete, thereby realizing effective removal of metal ions and organic matter.

[0024] As a preferred technical solution of the present application, the upward flow rate of the granulation zone is 10-100 m / h, for example 10 m / h, 20 m / h, 40 m / h, 60 m / h, 80 m / h, 100 m / h, etc. When the flow rate is within this range, the collision probability between polymer particles can be effectively increased, thereby completing the densification of the granulation under the action of water.

[0025] As a preferred technical solution of the present application, the metal ions include any one or more of calcium ions, magnesium ions, silicon ions, fluorine ions, lithium ions, manganese ions, lead ions, cobalt ions, and nickel ions.

[0026] As a preferred technical solution of the present application, the organic matter includes natural organic matter and / or artificially synthesized organic matter.

[0027] The wastewater treatment process provided by the present application first passes the wastewater into the crystallization zone to induce the metal ions in the water to generate crystalline bodies by using ion crystallization inducers, then enters the oxidation zone to modify the organic matter by combining the oxidation action of ozone, and then the ion crystalline bodies capture the modified organic matter to form crystalline polymers, enters the granulation zone to form granulation under the regulation of water action, and completes the removal of metal ions and organic pollutants through high-efficiency solid-liquid separation.

[0028] Secondly, the present invention provides a wastewater treatment device, comprising a crystallization zone, at least one oxidation zone and at least one granulation zone, wherein the top of the oxidation zone is connected to the top of the crystallization zone and the bottom of the oxidation zone is connected to the bottom of the granulation zone.

[0029] As a preferred embodiment of the present invention, the bottom of the crystallization zone is provided with an opening for the introduction of wastewater.

[0030] As a preferred embodiment of the present invention, the top of the granulation zone is provided with an opening for discharging clean water, and the bottom of the granulation zone is provided with an opening for discharging the granulated material.

[0031] As a preferred embodiment of the present invention, the bottom of the oxidation zone is provided with aeration holes to introduce ozone gas.

[0032] As a preferred embodiment of the present invention, the crystallization region is provided with an ion crystallization inducer.

[0033] As a preferred embodiment of the present invention, glass beads are provided at the bottom of the granulation zone.

[0034] As a preferred embodiment of the present invention, the granulation zone is provided with a reflux device to control the upward flow rate of the granulation zone, improve the flow state inside the granulation zone, promote the aggregation and coagulation of particles, and enhance the homogeneous granulation of crystals.

[0035] The wastewater treatment device provided by this invention involves rapidly and uniformly mixing wastewater in a crystallization zone to form ionic crystals. Subsequently, the wastewater overflows from the top of the crystallization zone to an oxidation zone where organic matter is oxidized and modified. The modified organic matter coordinates and complexes with the crystals to form polymers. Finally, the polymers flow from the bottom of the oxidation zone into a granulation zone, where they form dense granules under hydraulic control. The purified water is discharged from the top of the device, and the granules are discharged from the bottom. The wastewater treatment device provided by this invention can effectively remove metal ions and organic matter from the water.

[0036] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art:

[0037] The wastewater treatment process provided by this invention can effectively remove metal ions and organic matter from wastewater, enhance the treatment effect, improve solid-liquid separation efficiency, shorten the process flow, generate no chemical sludge, and has a small footprint, which is of great significance in the field of wastewater treatment. Attached Figure Description

[0038] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of the wastewater treatment device described in Embodiment 1 of the present invention;

[0041] Among them, 1-crystallization zone, 2-oxidation zone, and 3-granulation zone. Detailed Implementation

[0042] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0044] Example 1

[0045] This embodiment provides a wastewater treatment device, including a crystallization zone 1, an oxidation zone 2, and a granulation zone 3. The top of the oxidation zone 2 is connected to the top of the crystallization zone 1, and the bottom of the oxidation zone 2 is connected to the bottom of the granulation zone 3. The bottom of the crystallization zone 1 has an opening for wastewater to flow in, the top of the granulation zone 3 has an opening for draining clean water, and the bottom of the granulation zone 3 has an opening for discharging granulated material. The bottom of the oxidation zone 2 has an aeration hole for introducing ozone gas. The crystallization zone 1 contains a calcium ion crystallization inducer, and the bottom of the granulation zone 3 contains glass beads. A detailed structural diagram is shown below. Figure 1 As shown.

[0046] This embodiment also provides a wastewater treatment process, implemented by the above-mentioned wastewater treatment device, wherein the calcium ion concentration in the wastewater is 500 mg / L and the humic acid content is 20 mg / L; the process includes the following steps: wastewater is introduced into crystallization zone 1, where calcium ions in the wastewater react with an inducing agent to generate primary crystalline particles, which then overflow from the top of crystallization zone 1 to oxidation zone 2. Under the action of ozone, the humic acid in the water adsorbs and complexes with the crystalline particles to form crystalline aggregates, which then flow from the bottom of oxidation zone 2 to granulation zone 3. The granulation zone is equipped with a reflux adjustment to increase the upward flow rate and increase the collision probability between particles. Under the action of hydraulic force, the granules are densified. The purified water is discharged from the top of the granulation zone, and the granules are discharged from the bottom of the granulation zone. In this process, sodium carbonate is used as the ion crystallization inducer in the crystallization zone, and the molar ratio of the ion crystallization inducer to calcium ions is 1:1. The flow rate of ozone gas introduced into the oxidation zone is 1 mg / (mgCOD). The glass beads in the granulation zone have a particle size of 1-5 mm and a filling height of 20% of the total height of the granulation zone device. The hydraulic residence time in the crystallization zone is 4 min, the hydraulic residence time in the oxidation zone is 30 min, and the hydraulic residence time in the granulation zone is 20 min with an upward flow velocity of 50 m / h, resulting in purified water with a calcium ion concentration of 20 mg / L and a humic acid content of 5 mg / L.

[0047] Example 2

[0048] This embodiment provides a wastewater treatment process and apparatus. The apparatus is the same as in Embodiment 1, wherein the calcium ion concentration in the wastewater is 500 mg / L and the humic acid content is 20 mg / L.

[0049] The wastewater treatment process includes the following steps: wastewater is introduced into crystallization zone 1, where calcium ions react with an inducing agent to generate primary crystalline particles. These particles then overflow from the top of crystallization zone 1 to oxidation zone 2. Under the action of ozone, humic acid in the water adsorbs and complexes with the crystalline particles to form crystalline aggregates. These aggregates then flow from the bottom of oxidation zone 2 to granulation zone 3. The granulation zone is equipped with a reflux system to adjust the upward flow rate and increase the probability of collisions between particles. Under hydraulic action, the granules are densified. The purified water is discharged from the top of the granulation zone, and the granules are discharged from the bottom of the granulation zone. In this process, sodium carbonate is used as the ion crystallization inducer in the crystallization zone, and the molar ratio of the ion crystallization inducer to metal ions is 0.8:1. The flow rate of ozone gas introduced into the oxidation zone is 2 mg / (mgCOD). The glass beads in the granulation zone have a particle size of 1-5 mm and a filling height of 10% of the total height of the granulation zone device. The hydraulic residence time in the crystallization zone is 5 min, the hydraulic residence time in the oxidation zone is 10 min, the hydraulic residence time in the granulation zone is 5 min, and the upward flow velocity is 100 m / h, resulting in purified water with a calcium ion concentration of 30 mg / L and a humic acid content of 6 mg / L.

[0050] Example 3

[0051] This embodiment provides a wastewater treatment process and apparatus. The apparatus is the same as in Embodiment 1, wherein the calcium ion concentration in the wastewater is 500 mg / L and the humic acid content is 20 mg / L.

[0052] The wastewater treatment process includes the following steps: wastewater is introduced into crystallization zone 1, where calcium ions react with an inducing agent to generate primary crystalline particles. These particles then overflow from the top of crystallization zone 1 to oxidation zone 2. Under the action of ozone, humic acid in the water adsorbs and complexes with the crystalline particles to form crystalline aggregates. These aggregates then flow from the bottom of oxidation zone 2 to granulation zone 3. The granulation zone is equipped with a reflux system to adjust the upward flow rate and increase the probability of collisions between particles. Under hydraulic action, the granules are densified. The purified water is discharged from the top of the granulation zone, and the granules are discharged from the bottom of the granulation zone. In this process, sodium carbonate is used as the ion crystallization inducer in the crystallization zone, and the molar ratio of the ion crystallization inducer to metal ions is 1.5:1. The flow rate of ozone gas introduced into the oxidation zone is 0.1 mg / (mgCOD). The glass beads in the granulation zone have a particle size of 1-5 mm and a filling height of 5% of the total height of the granulation zone device. The hydraulic residence time in the crystallization zone is 2 min, the hydraulic residence time in the oxidation zone is 60 min, and the hydraulic residence time in the granulation zone is 40 min with an upward flow velocity of 10 m / h. The purified water has a calcium ion concentration of 8 mg / L and a humic acid content of 12 mg / L.

[0053] Examples 1-3 show that the wastewater treatment process and apparatus provided by the present invention can effectively remove metal ions and organic matter from wastewater, enhance the treatment effect, improve solid-liquid separation efficiency, shorten the process flow, generate no chemical sludge, and occupy a small area.

[0054] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0055] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily 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 invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wastewater treatment process, characterized in that, The process includes the following steps: wastewater is sequentially passed through a crystallization zone, an oxidation zone, and a granulation zone for treatment to obtain purified water; The wastewater contains metal ions and organic matter; The crystallization zone performs ion crystallization to form ion crystals, the oxidation zone performs organic oxidation modification, the modified organic matter coordinates and complexes with the ion crystals to form polymers, and the granulation zone causes the polymers to form granules. The crystallization zone is provided with an ion crystallization inducer, and the molar ratio of the ion crystallization inducer to metal ions is 0.8-1.5:1; The oxidation zone is exposed to ozone gas at a rate of 0.1-2 mg / (mgCOD). The granulation zone is equipped with glass beads, and the filling height of the glass beads is 5-20% of the total height of the granulation zone. The ion crystallization inducer is selected from carbonates, sulfates, and silicates; The metal ions include any one or more of calcium ions, magnesium ions, silicon ions, fluorine ions, lithium ions, manganese ions, lead ions, cobalt ions, and nickel ions. The organic matter includes natural organic matter and / or artificially synthesized organic matter.

2. The wastewater treatment process according to claim 1, characterized in that, The wastewater enters from the bottom of the crystallization zone, overflows from the top of the crystallization zone to the oxidation zone, and flows from the bottom of the oxidation zone into the granulation zone.

3. The wastewater treatment process according to claim 1 or 2, characterized in that, The glass beads have a particle size of 1-5 mm.

4. The wastewater treatment process according to claim 1 or 2, characterized in that, The hydraulic residence time in the crystallization zone is 2-5 minutes. And / or, the hydraulic retention time in the oxidation zone is 10-60 min; And / or, the hydraulic retention time in the granulation zone is 5-40 min.

5. The wastewater treatment process according to claim 1 or 2, characterized in that, The upward flow velocity in the granulation zone is 10-100 m / h.

6. A wastewater treatment device, characterized in that, It includes a crystallization zone, at least one oxidation zone, and at least one granulation zone, wherein the top of the oxidation zone is connected to the top of the crystallization zone, and the bottom of the oxidation zone is connected to the bottom of the granulation zone, for implementing the wastewater treatment process according to any one of claims 1-5.

7. The wastewater treatment apparatus according to claim 6, characterized in that, The bottom of the crystallization zone is provided with an opening to allow wastewater to flow in; And / or, the top of the granulation zone is provided with an opening for draining clean water, and the bottom of the granulation zone is provided with an opening for draining the granulated material.

8. The wastewater treatment apparatus according to claim 6 or 7, characterized in that, Aeration holes are provided at the bottom of the oxidation zone; And / or, the crystallization region is provided with an ion crystallization inducer; And / or, glass beads are provided at the bottom of the granulation zone.

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