Device for treating DDNP (dinitrodiazophenol) wastewater by combined process

Abstract

The utility model discloses a device for treating DDNP (dinitrodiazophenol) wastewater by a combined process. The device comprises a screening filter, a regulating tank, a sedimentation tank, an oxidation tank and an electrolytic tank, the screening filter is used for filtering the entering DDNP wastewater; the regulating tank is connected with the screening filter tank, and is used for regulating the pH of the DDNP wastewater subjected to filtration treatment to be acidic; the sedimentation tank is connected with the regulating tank, is used for carrying out sedimentation treatment on the DDNP subjected to acid regulation treatment and removing visible suspended matters in a water body, and comprises a sedimentation chamber, a dosing tank which is connected with the sedimentation chamber and is used for adding a water purifying agent into the sedimentation chamber, a filter screen arranged in the sedimentation chamber and a stirring part which is connected with the filter screen and extends downwards; the oxidation pond is connected with the settling chamber and is used for converting and decomposing part of soluble organic matters in the entering supernate into inorganic matters; the electrolytic tank is connected with the oxidation tank and is used for carrying out electrolytic reaction on the entering DDNP wastewater; through the composition of the limiting device, the DDNP wastewater is deeply treated, so that high-chroma and a large number of toxic organic matters in the DDNP wastewater can be deeply removed, and the effluent meeting the emission standard requirement is obtained.

Description

Technical Field

[0001] The utility model belongs to the field of DDNP wastewater treatment, and particularly relates to a device for treating DDNP wastewater by a combined process. Background Technique

[0002] Dinitrophenol diazo is a nitro derivative of phenol (abbreviation: DDNP). Due to its advantages such as low mechanical sensitivity, high flame sensitivity, and excellent initiation performance, it is an important primary explosive in the detonator industry. The DDNP production wastewater mainly comes from the reduction, diazotization washing processes and the drainage of flushing the ground, equipment, and tools. The wastewater has a large production volume, high toxicity, high chroma, and high COD concentration, which has always been a key and difficult problem in the production of the gunpowder industry and the environmental protection system.

[0003] Currently, the DDNP production wastewater treatment technologies at home and abroad are divided into physical and chemical methods and biochemical methods. The physical and chemical methods can reduce the chroma and the concentration of toxic substances, and have a certain treatment effect. However, as an independent treatment process, it usually cannot make the wastewater meet the discharge standards. The biochemical method has a mature process, stable operation, but has high process technical requirements. The activities of microorganisms are easily interfered and damaged, it occupies a large area, and the decolorization effect is poor. When the two are used in combination, due to the complex process, harsh reaction conditions, and poor effluent effect, there may still be a situation where the chroma of the wastewater is relatively high and the COD index fails to reach the discharge standard.

[0004] The chroma of DDNP wastewater is very high, and the pH value of the reduction wastewater is between 12 and 13.5, while the pH of the diazo wastewater is between 1.5 and 1.7, and the pH of the flushing water is close to neutral. All of them are not suitable for separate disposal. Therefore, they are mixed for comprehensive treatment. After mixing, the water quality of the wastewater is pH 5 - 6, chroma 7600 times, CODcr is between 2250 - 2500 mg / L, and it contains a large amount of nitro compounds such as dinitrophenol diazo and its by-products (azo compounds), which are difficult to treat. Direct discharge of untreated DDNP wastewater into rivers will seriously pollute the environment. The innovation of DDNP wastewater treatment technology affects the development of the gunpowder industry. Currently, the DDNP wastewater treatment technology used in the pyrotechnics industry has a situation where the effluent chroma is relatively high and the COD index fails to reach the discharge standard, and there is a need to further develop a combined process with obvious treatment effect, simple operation, and low operating cost. Summary of the Invention

[0005] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a device for treating DDNP wastewater by a combined process.

[0006] The utility model adopts the following technical scheme:

[0007] A device for treating DDNP wastewater by a combined process includes a screening tank, an adjustment tank, a sedimentation tank, an oxidation tank, and an electrolytic tank;

[0008] A sieve filter tank that filters the incoming DDNP wastewater;

[0009] A regulating tank, connected to the sieve filter tank, regulates the pH of the DDNP wastewater after filtration to be acidic;

[0010] A sedimentation tank, connected to the regulating tank, conducts sedimentation treatment on the acidified DDNP wastewater to remove visible suspended solids in the water body, including a sedimentation chamber, a chemical dosing tank connected to the sedimentation chamber for injecting a water purifying agent into the sedimentation chamber, a filter screen arranged in the sedimentation chamber, and a stirring member connected to the filter screen and extending downward;

[0011] An oxidation tank, connected to the sedimentation chamber, decomposes some dissolved organic matters in the incoming supernatant into inorganic matters, including an oxidation chamber, an inlet connected to the oxidation chamber, an outlet connected to the oxidation chamber and located above the inlet, and a diversion mechanism arranged in the oxidation chamber opposite to the outlet;

[0012] An electrolytic cell, connected to the oxidation tank, conducts an electrolytic reaction on the incoming DDNP wastewater to electrolyze the low-concentration dissolved organic matters in the DDNP wastewater.

[0013] Furthermore, the diversion mechanism includes a plurality of diversion cross plates arranged in a staggered manner up and down at the upper end of the oxidation tank and two diversion vertical plates oppositely arranged on both sides of the plurality of diversion cross plates. The diversion vertical plates are connected to the ends of the opposite diversion cross plates, so that an upward-winding diversion channel is formed between the plurality of diversion cross plates and the two diversion vertical plates, and the outlet is connected to the upper end of the diversion channel.

[0014] Furthermore, the regulating tank includes a regulating chamber, a stirring paddle rotatably arranged in the regulating chamber, a pH detector arranged in the regulating chamber, and an acid agent dosing chamber for supplying an acid agent to the regulating chamber.

[0015] Furthermore, the oxidation tank further includes an oxidant dosing chamber connected to the oxidation chamber for supplying an oxidant.

[0016] Furthermore, the electrolytic cell includes an electrolytic chamber and a BDD electrode group arranged in the electrolytic chamber. The BDD electrode group includes a BDD electrode and two inert electrodes oppositely arranged on both sides of the BDD electrode.

[0017] Furthermore, the sieve filter tank includes a sieve filtering chamber and a sieve filter arranged in the sieve filtering chamber. The opposite surface of the sieve filter to the wastewater flow direction is an inclined surface.

[0018] Furthermore, it further includes an effluent tank connected to the electrolytic cell and a monitor connected to the effluent tank for detecting the wastewater effluent index.

[0019] Furthermore, it further includes a water inlet tank connected to the sieve filter tank for conveying wastewater to the sieve filter tank.

[0020] As described above for the present utility model, compared with the prior art, the beneficial effects of the present utility model are as follows: By defining the composition of the device, through the cooperation of the regulating tank, sedimentation tank, oxidation tank and electrolytic cell, the DDNP wastewater is deeply treated, so that the high chromaticity and a large amount of toxic organic substances in the DDNP wastewater can be deeply removed to obtain the effluent meeting the discharge standard requirements.

[0021] By defining the structure of the diversion mechanism, the treated DDNP wastewater flows smoothly and maintains a certain flow rate to be discharged through the water outlet, reducing energy loss and ensuring the normal operation of the device.

[0022] By defining the composition of the BDD electrode group, the BDD electrode and the two inert electrodes respectively form independent electrolytic regions. Among them, the two electrolytic regions are independent of each other, and share the ion exchange membrane to be connected to each other, thereby realizing precise control. At the same time, the electrolytic reaction efficiency can be improved and the system flexibility can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of the present utility model;

[0024] In the figure, 1 - water inlet tank, 2 - screening tank, 3 - regulating tank, 4 - sedimentation tank, 5 - oxidation tank, 6 - electrolytic cell, 7 - water outlet tank, 8 - monitor, 21 - screening chamber, 22 - screening filter, 33 - inclined surface, 31 - regulating chamber, 32 - stirring paddle, 33 - pH monitor, 34 - acid agent dosing chamber, 41 - sedimentation chamber, 42 - dosing tank, 43 - filter screen, 44 - stirring member, 51 - oxidation chamber, 52 - water inlet, 53 - water outlet, 54 - diversion mechanism, 541 - diversion cross plate, 542 - diversion vertical plate, 543 - diversion channel, 55 - oxidant dosing chamber, 61 - electrolytic chamber, 62 - BDD electrode group, 63 - BDD electrode, 64 - inert electrode. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The following further describes the present utility model through specific embodiments.

[0026] Refer to Figure 1 As shown, a device for treating DDNP wastewater by a combined process includes a water inlet tank 1, a screening tank 2, a regulating tank 3, a sedimentation tank 4, an oxidation tank 5, an electrolytic cell 6, a water outlet tank 7 and a monitor 8.

[0027] The water inlet tank 1 is used to store the recycled DDNP wastewater to be treated.

[0028] The screening filter tank 2 is connected to the water inlet tank 1 and filters the incoming DDNP wastewater. It includes a screening chamber 21 and a screening filter mesh 22 arranged in the screening chamber 21. Specifically, the opposite surface of the screening filter mesh 22 to the wastewater flow direction is an inclined surface 23 to increase the contact area between the screening filter mesh 22 and the DDNP wastewater and improve the filtering effect on the DDNP wastewater.

[0029] The adjustment tank 3 is connected to the screening filter tank 2 and adjusts the pH of the DDNP wastewater after filtration treatment to be acidic. It includes an adjustment chamber 31, a stirring paddle 32 rotatably arranged in the adjustment chamber 31, a pH detector 33 arranged in the adjustment chamber 31, and an acid agent dosing chamber 34 for supplying acid agent to the adjustment chamber 31. Acid agent is added to the DDNP wastewater through the acid agent dosing chamber 34 to adjust the pH value of the DDNP wastewater between 2 and 3 to meet the subsequent treatment requirements.

[0030] The sedimentation tank 4 is connected to the adjustment tank 3 and performs sedimentation treatment on the acid-adjusted DDNP to remove visible suspended solids in the water body. It includes a sedimentation chamber 41, a dosing tank 42 connected to the sedimentation chamber 41 for injecting a water purification agent into the sedimentation chamber 41, a filter mesh 43 arranged in the sedimentation chamber 41, and a stirring member 44 connected to the filter mesh 43 and extending downward; during sedimentation treatment, the dosing tank 42 injects a water purification agent into the sedimentation chamber 41, and the stirring member 44 works to mix the water purification agent and the wastewater evenly. The water purification agent agglomerates the small particle suspended solids in the wastewater together, and then is isolated by the filter mesh 43 to isolate the visible suspended solids in the upward flowing wastewater to achieve the effect of removing suspended solids in the wastewater; specifically, the stirring member 44 is a commonly used device in the field of stirring equipment, and its specific structure and working principle will not be further elaborated here.

[0031] The oxidation tank 5 is connected to the sedimentation chamber 41 and decomposes some dissolved organic matters in the incoming supernatant into inorganic matters. It includes an oxidation chamber 51, a water inlet 52 connected to the oxidation chamber 51, a water outlet 53 connected to the oxidation chamber 51 and located above the water inlet 52, a flow guiding mechanism 54 arranged in the oxidation chamber 51 opposite to the water outlet 53, and an oxidant dosing chamber 55 connected to the oxidation chamber 51 for supplying an oxidant. Specifically, the flow guiding mechanism 54 includes a plurality of flow guiding cross plates 541 arranged at the upper end of the oxidation chamber 51 in a staggered up and down manner and two flow guiding vertical plates 542 oppositely arranged on both sides of the plurality of flow guiding cross plates 541. Among them, the flow guiding vertical plates 542 are connected to the ends of the opposite flow guiding cross plates 541, so that an upward winding flow guiding channel 543 is formed between the plurality of flow guiding cross plates 541 and the two flow guiding vertical plates 542. The water outlet 53 is connected to the upper end of the flow guiding channel 543. By defining the structure of the flow guiding mechanism 54, the treated DDNP wastewater flows smoothly and maintains a certain flow rate and is discharged through the water outlet 53, reducing energy loss and ensuring the normal operation of the device; further, the oxidant is ferrous sulfate and hydrogen peroxide, and the specific reaction principle refers to the Fenton method.

[0032] The electrolytic cell 6, which is connected to the oxidation cell 5, conducts an electrolytic reaction on the incoming DDNP wastewater to electrolyze the low-concentration dissolved organic matter in the DDNP wastewater. It includes an electrolytic chamber 61 and a BDD electrode group 62 arranged in the electrolytic chamber 61. Specifically, the BDD electrode group 62 includes a BDD electrode 63 and two inert electrodes 64 oppositely arranged on both sides of the BDD electrode 63, such that the BDD electrode 63 and the two inert electrodes 64 respectively form independent electrolytic regions. The incoming wastewater is subjected to electrocatalytic oxidation treatment by the BDD electrode group 62, and when the indexes such as COD and chromaticity of the wastewater meet the standards, it is discharged to the effluent tank; wherein, the electrode spaces in the double electrolytic regions are independent of each other and are connected to each other by sharing an ion exchange membrane, thereby realizing precise control, improving the electrolytic reaction efficiency at the same time, and increasing the system flexibility; further, the type of the inert electrode 64 can be selected according to the treatment parameters of the wastewater, and no further description is made here for its selection.

[0033] The monitor 8, which is connected to the effluent tank 7, is used to detect whether the effluent chromaticity and COD of the wastewater in the effluent tank 7 meet the effluent indexes.

[0034] In this application, by defining the composition of the device, through the cooperation of the regulating tank 3, the sedimentation tank 4, the oxidation cell 5 and the electrolytic cell 6, the DDNP wastewater is deeply treated, so that the high chromaticity and a large amount of toxic organic matter in the DDNP wastewater can be deeply removed to obtain effluent that meets the discharge standard requirements.

[0035] The above is only a preferred embodiment of the present utility model, and thus cannot limit the scope of implementation of the present utility model. That is, equivalent changes and modifications made according to the scope of the present utility model application and the content of the specification should still fall within the scope covered by the present utility model application.

Claims

1. An apparatus for treating DDNP wastewater by a combined process, characterized in that: It includes a screening filter, an adjustment tank, a sedimentation tank, an oxidation tank and an electrolytic cell; The screening filter filters the incoming DDNP wastewater; The adjustment tank is connected to the screening filter and adjusts the pH of the filtered DDNP wastewater to acidic; The sedimentation tank is connected to the adjustment tank and performs sedimentation treatment on the acid-adjusted DDNP to remove visible suspended solids in the water body. It includes a sedimentation chamber, a chemical dosing tank connected to the sedimentation chamber for injecting a water purifying agent into the sedimentation chamber, a filter screen arranged in the sedimentation chamber, and a stirring member connected to the filter screen and extending downward; The oxidation tank is connected to the sedimentation chamber and decomposes some dissolved organic matter in the incoming supernatant into inorganic matter. It includes an oxidation chamber, an inlet connected to the oxidation chamber, an outlet connected to the oxidation chamber and located above the inlet, and a diversion mechanism arranged in the oxidation chamber and opposite to the outlet; The electrolytic cell is connected to the oxidation tank and performs an electrolytic reaction on the incoming DDNP wastewater to electrolyze the low-concentration dissolved organic matter in the DDNP wastewater.

2. The device for treating DDNP wastewater by a combined process according to claim 1, wherein: The diversion mechanism includes a plurality of diversion cross plates arranged in a vertically staggered manner at the upper end of the oxidation tank and two diversion vertical plates oppositely arranged on both sides of the plurality of diversion cross plates. The diversion vertical plates are connected to the ends of the opposite diversion cross plates, so that an upward-winding diversion channel is formed between the plurality of diversion cross plates and the two diversion vertical plates, and the outlet is connected to the upper end of the diversion channel.

3. The device for treating DDNP wastewater by a combined process according to claim 1, wherein: The adjustment tank includes an adjustment chamber, a stirring paddle rotatably arranged in the adjustment chamber, a pH detector arranged in the adjustment chamber, and an acid agent dosing chamber for supplying an acid agent to the adjustment chamber.

4. The device for treating DDNP wastewater by a combined process according to claim 1, characterized in that: The oxidation tank further includes an oxidant dosing chamber connected to the oxidation chamber for supplying an oxidant.

5. The device for treating DDNP wastewater by a combined process according to claim 1, characterized in that: The electrolytic cell includes an electrolysis chamber and a BDD electrode group arranged in the electrolysis chamber. The BDD electrode group includes a BDD electrode and two inert electrodes oppositely arranged on both sides of the BDD electrode.

6. The device for treating DDNP wastewater by a combined process according to claim 1, characterized in that: The screening filter includes a screening chamber and a screening filter screen arranged in the screening chamber. The opposite surface of the screening filter screen to the wastewater flow direction is an inclined surface.

7. An apparatus for treating DDNP wastewater by a combined process according to claim 1, characterized in that: It also includes an effluent tank connected to the electrolytic cell and a monitor connected to the effluent tank for detecting the wastewater effluent index.

8. The device for treating DDNP wastewater by a combined process according to claim 1, wherein: It also includes a water inlet tank connected to the screening filter for transporting wastewater to the screening filter.

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