Vanadium precipitation wastewater treatment device

Abstract

The utility model discloses a vanadium precipitation wastewater treatment device which comprises the following systems which are connected in sequence: a pretreatment system which comprises a heat exchanger and a filter, the heat exchanger is used for cooling vanadium precipitation wastewater, and the filter is used for removing impurities from the cooled vanadium precipitation wastewater; the resin adsorption system is used for adsorbing hexavalent chromium in the pretreated vanadium precipitation wastewater to obtain resin effluent and adsorbed resin; and the regeneration system is used for desorbing the adsorbed resin to obtain a regenerated concentrated solution. By adopting the device disclosed by the utility model, hexavalent chromium in the vanadium precipitation wastewater can be recycled, and the problems of high recycling cost and complicated operation are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater treatment, in particular to a vanadium precipitation wastewater treatment device. Background Art

[0002] In the steel smelting industry, hexavalent chromium (Cr 6+ ) is the primary associated harmful element. Hexavalent chromium is classified as a Class I carcinogen by the World Health Organization. Direct discharge can severely pollute the environment, while human contact or ingestion can cause serious harm, including allergies, vomiting, dermatitis, and gastric ulcers. Therefore, controlling and handling hexavalent chromium generated during production is crucial.

[0003] The content of hexavalent chromium in vanadium precipitation wastewater is about 1000 mg / L. There are two commonly used methods for treating hexavalent chromium: one is to add ferrous sulfate (FeSO4) under acidic conditions to reduce hexavalent chromium to trivalent chromium (Cr 3+ ), followed by the addition of lime, and the mixed sludge formed by precipitation is transported for disposal; the other is to use sodium metabisulfite (Na2S2O5) to reduce hexavalent chromium to trivalent chromium under acidic conditions, and then add sodium hydroxide (NaOH) to form chromium hydroxide (Cr(OH)3) mud, which can be sold as a product. The first treatment method does not recover hexavalent chromium, and the hexavalent chromium is eventually transported for disposal as sludge and cannot be used as a resource. Although the second treatment method recovers hexavalent chromium, the recovery cost is relatively high. Therefore, there is a need for a vanadium precipitation wastewater treatment device that can recycle hexavalent chromium and has a low recovery cost. Summary of the Invention

[0004] In order to solve the above technical problems existing in the prior art, the present invention provides a vanadium precipitation wastewater treatment device, which includes the following systems connected in sequence:

[0005] The pretreatment system includes a heat exchanger and a filter. The heat exchanger is used to cool the vanadium precipitation wastewater, and the filter is used to remove impurities from the cooled vanadium precipitation wastewater.

[0006] Resin adsorption system, used to adsorb hexavalent chromium in pretreated vanadium precipitation wastewater to obtain resin effluent and adsorbed resin;

[0007] The regeneration system is used to desorb the adsorbed resin to obtain regenerated concentrated liquid.

[0008] Preferably, the heat exchanger is a shell and tube heat exchanger. Of course, in other embodiments of the present invention, the heat exchanger can also be a plate heat exchanger or other types of heat exchangers commonly used in the art, as long as the cooling effect on the vanadium precipitation wastewater can be achieved.

[0009] The filter is used to remove insoluble impurities in the vanadium precipitation wastewater, and is preferably a bag filter with a maximum flow rate of 2000 L / min. Of course, in other embodiments of the present invention, the filter can also be a high-precision liquid filter commonly used in industry.

[0010] Preferably, the resin adsorption system comprises a plurality of adsorption columns.

[0011] Preferably, the adsorption column is filled with anion adsorption resin.

[0012] Preferably, the filling height of the adsorption resin in the adsorption column is 60%-80% of the height of the adsorption column.

[0013] Preferably, the vanadium precipitation wastewater treatment device further comprises a feeding system, the discharge port of the feeding system is connected to the feed port of the pretreatment system, and is used to introduce the vanadium precipitation wastewater into the pretreatment system.

[0014] Preferably, the vanadium precipitation wastewater treatment device further comprises a liquid storage system, wherein the feed port of the liquid storage system is connected to the regeneration liquid outlet of the regeneration system for storing the regeneration concentrated liquid.

[0015] Preferably, the filtration pore size of the filter is 50-100 μm.

[0016] The vanadium precipitation wastewater treatment device of this utility model is suitable for treating vanadium precipitation wastewater and recovering the hexavalent chromium contained in the wastewater. This solution uses a specialized resin for exchange adsorption to first adsorb the hexavalent chromium from the wastewater. Once the resin is saturated with adsorption, a regeneration system is used to extract the adsorbed hexavalent chromium and transfer it into a regenerated concentrate. This regenerated hexavalent chromium concentrate can be sold as a product. This solution allows for the recovery of hexavalent chromium at a low disposal cost, with continuous and simple operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure shows the connection diagram of the vanadium precipitation wastewater treatment device in the present invention.

[0018] Reference numerals:

[0019] 1-heat exchanger; 2-filter; 3-resin adsorption system; 4-regeneration system, 5-liquid storage system. DETAILED DESCRIPTION

[0020] The following is an explanation of the implementation of the present invention by means of specific specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this utility model are limited to this implementation. On the contrary, the purpose of introducing the utility model in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide an in-depth understanding of the present invention, the following description will contain many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0021] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0022] In the description of this embodiment, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this embodiment based on the specific circumstances.

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0024] According to one embodiment of the present invention, referring to Figure 1When the vanadium precipitation wastewater treatment device of this embodiment is used to treat vanadium precipitation wastewater, the vanadium precipitation wastewater is stored in a feeding system (not shown). At this time, the temperature of the vanadium precipitation wastewater is between 80-90°C. The vanadium precipitation wastewater enters the pretreatment system through the discharge port of the feeding system through a pump provided between the feeding system and the pretreatment system. In this embodiment, the pretreatment system includes a heat exchanger 1 and a filter 2 connected in sequence. The heat exchanger 1 is a shell and tube heat exchanger for cooling the vanadium precipitation wastewater, and the filter 2 is a bag filter for removing impurities from the cooled vanadium precipitation wastewater. Among them, the filter pore size of the filter is distributed between 50-100 microns, and the average filter pore size is about 70 microns. In this embodiment, the heat exchanger 1 can reduce the temperature of the vanadium precipitation wastewater to below 40°C. After cooling and impurity removal, the vanadium precipitation wastewater enters the resin adsorption system 3, and the hexavalent chromium in the pretreated vanadium precipitation wastewater is adsorbed by the resin. In this embodiment, the resin adsorption system 3 includes two adsorption columns filled with anionic adsorption resin. During treatment, the vanadium precipitation wastewater first passes through the ion exchange resin and then the anionic adsorption resin. The adsorption resin filling height in the adsorption columns is 60%-80% of the column height. Of course, in other embodiments of the utility model, the number of adsorption columns in the resin system, the type of filling resin, and the specifications of the adsorption columns can be adjusted according to actual needs.

[0025] After the exchange adsorption action of the resin adsorption system, the hexavalent chromium in the vanadium precipitation wastewater is adsorbed to obtain resin effluent and adsorbed resin. The concentration of hexavalent chromium in the resin effluent is below 0.1 mg / L, which meets the comprehensive sewage discharge standard. The adsorbed resin is desorbed in the regeneration system 4. The regeneration liquid used in the regeneration system 4 is a 5wt% sodium hydroxide solution. The flow rate of the regeneration liquid during regeneration is 4.0 m / h, and the regeneration liquid consumption is 1.5 times the resin filling volume to obtain a regenerated concentrated liquid. In this embodiment, the vanadium precipitation wastewater treatment device also includes a liquid storage system 5, and the feed port of the liquid storage system 5 is connected to the regeneration liquid outlet of the resin adsorption system 3 for storing the regeneration concentrated liquid.

[0026] Of course, in other embodiments of the present invention, during regeneration, the concentration of sodium hydroxide in the regeneration solution can be between 3wt% and 6wt%, the flow rate of the regeneration solution can be between 3.0 and 5.0 m / h, and the regeneration solution consumption can be 1 to 1.5 times the resin filling volume. When the resin is saturated with adsorption, the regeneration system 4 desorbs the hexavalent chromium adsorbed by the resin and restores the resin's ability to adsorb hexavalent chromium, allowing the resin to enter the next adsorption cycle. The hexavalent chromium in the vanadium precipitation wastewater is transferred to the regeneration concentrate, which can be sold as a product.

[0027] By treating vanadium precipitation wastewater with the device of the utility model, the hexavalent chromium therein can be recovered and utilized at a relatively low cost and through a simple process, thus achieving considerable economic benefits.

[0028] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above description is provided to further illustrate the present invention in conjunction with specific embodiments, and that the present invention should not be construed as being limited to these descriptions. Those skilled in the art may make various changes in form and detail, including simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A vanadium precipitation wastewater treatment device, characterized in that: The device comprises the following systems connected in sequence: A pretreatment system, comprising a heat exchanger and a filter, wherein the heat exchanger is used to cool the vanadium precipitation wastewater, and the filter is used to remove impurities from the cooled vanadium precipitation wastewater; A resin adsorption system is used to use resin to adsorb hexavalent chromium in the pretreated vanadium precipitation wastewater to obtain resin effluent and adsorbed resin; The regeneration system is used to desorb the adsorbed resin to obtain regenerated concentrated liquid.

2. The device according to claim 1, wherein The resin adsorption system includes a plurality of adsorption columns.

3. The device according to claim 2, wherein The adsorption column is filled with anion adsorption resin.

4. The device according to any one of claims 2 to 3, characterized in that The filling height of the adsorption resin in the adsorption column is 60%-80% of the height of the adsorption column.

5. The device according to any one of claims 1 to 3, characterized in that The device further comprises a feeding system, wherein the discharge port of the feeding system is connected to the feeding port of the pretreatment system and is used for introducing vanadium precipitation wastewater into the pretreatment system.

6. The device according to any one of claims 1 to 3, characterized in that The device further comprises a liquid storage system, wherein the feed port of the liquid storage system is connected to the regeneration liquid discharge port of the regeneration system and is used for storing the regeneration concentrated liquid.

7. The device according to any one of claims 1 to 3, characterized in that The filter has a filtration pore size of 50-100 μm.

8. The device according to any one of claims 1 to 3, characterized in that The heat exchanger is a shell and tube heat exchanger.

9. The device according to any one of claims 1 to 3, characterized in that The filter is a bag filter.

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