A water treatment device for treating iron-manganese mine wastewater

Abstract

The invention relates to a water treatment device for treating iron-manganese mine wastewater, comprising a nano aerator, an aeration oxidation tank, a manganese sand filter tank and a water production tank connected in sequence, wherein the nano aerator is connected to a nano aeration pipe at the bottom of the aeration oxidation tank to provide nano gas for the aeration oxidation tank to oxidize the mine wastewater; the manganese sand filter tank comprises a water distributor, a backwash outlet, a plurality of manganese sand filter layers, a backwash air pipe, a backwash water pipe and a water production port from top to bottom, the water outlet of the aeration oxidation tank is connected to the water distributor, the wastewater after oxidation treatment flows through the manganese sand filter layer after water distribution, and is discharged into the water production tank through the water production port; the water production port is connected to the water production tank, and the backwash outlet is connected to the water inlet of the aeration oxidation tank; the water production tank is connected to the backwash water pipe through a backwash pipe to backwash the manganese sand filter layer, and the wastewater after backwashing is returned to the aeration oxidation tank for treatment.

Description

Technical Field

[0001] The invention belongs to the technical field of iron-manganese mine wastewater treatment, and in particular relates to a water treatment device for treating iron-manganese mine wastewater. Background Art

[0002] Mine wastewater is an industrial wastewater produced during coal mining that contains high concentrations of metal elements such as iron and manganese. The iron and manganese in mine wastewater are mostly in the form of Fe 2+ , Mn 2+ The iron and manganese are in a low-price state, and iron and manganese exist almost at the same time. Excessive iron and manganese concentrations will affect the sensory perception of the water body. When the iron concentration in the water is greater than 0.3mg / L, the water body will become turbid. When it is greater than 1mg / L, there will be an iron smell. Iron-containing water will cause rust spots on utensils, and yellow or brown stains will appear on washed clothes. Iron sediments will breed iron bacteria, block pipes, and sometimes red water will appear. Manganese pollution is more serious than iron pollution. When the manganese concentration is higher than 0.3mg / L, the water will have an odor and form spots on utensils. Excessive manganese will damage the human central nervous system. Drinking water with high iron and manganese content for a long time will seriously affect your health. For this reason, my country's "Sanitary Standards for Drinking Water" (GB5749-85) stipulates that the iron content is ≤0.3mg / L and the manganese content is ≤0.1mg / L. Raw water that exceeds the standard must be treated to remove iron and manganese.

[0003] At present, the commonly used methods for removing iron and manganese from mine wastewater are natural oxidation, contact oxidation and biological methods. The natural oxidation method is to aerate the mine wastewater and remove Fe 2+ Oxidized to Fe 3+ It is precipitated in the form of Fe(OH)3 and removed by precipitation and filtration. When removing manganese, alkali must be added, which is a complex process and has a high cost. 2+ With Mn 2+ Microorganisms with biological oxidation function can achieve the purpose of removing iron and manganese from water, but there are problems such as long microbial cultivation cycle.

[0004] The contact oxidation method uses natural manganese sand or modified manganese sand to adsorb and / or oxidize the dissolved divalent iron or divalent manganese, respectively, and then remove it by filtration. However, there are some problems with the existing contact oxidation method, such as the manganese sand filter material will face clogging problems after long-term filtration, the manganese content of the wastewater treated with manganese sand cannot meet the requirements for reuse, and in the use of manganese sand filters, the water inlet is uneven, and the bubbles generated by ordinary air compressors are in contact with the wastewater for a short time. Summary of the invention

[0005] In view of the above problems, the present invention provides a water treatment device for treating iron-manganese mine wastewater, comprising a nano-aerator, an aeration oxidation tank, a manganese sand filter tank and a water production tank connected in sequence, wherein the nano-aerator is connected to a nano-aeration pipe at the bottom of the aeration oxidation tank to provide nano-gas to the aeration oxidation tank to oxidize and treat the mine wastewater;

[0006] The manganese sand filter pool includes a water distributor, a backwash outlet, several layers of manganese sand filter layers, a backwash water pipe and a water outlet from top to bottom. The water outlet of the aeration oxidation tank is connected to the water distributor. After the wastewater after oxidation treatment passes through the manganese sand filter layer, it is discharged into the water production tank through the water outlet. The water outlet is connected to the water production tank, and the backwash outlet is connected to the water inlet of the aeration oxidation tank.

[0007] The water production tank is connected to the backwash water pipe through the backwash pipeline, which is used for backwashing the manganese sand filter layer. The sewage after backwashing is returned to the aeration oxidation tank for treatment.

[0008] Optionally, the air inlet of the nano aerator is connected to an air inlet pipe, the air inlet pipe inputs air or oxygen, the liquid inlet of the nano aerator is connected to the aeration oxidation tank through a circulating water pipe, and the air outlet of the nano aerator is connected to the nano aeration pipe.

[0009] Optionally, the aeration oxidation pond comprises a water inlet, a circulating water outlet, a water outlet, a plurality of baffles and a nano aeration tube, the water inlet is arranged at the top of the aeration oxidation pond, the water outlet is arranged on the side wall of the aeration oxidation pond opposite to the water inlet, and the circulating water outlet is arranged below the water inlet for connecting to the circulating water pipe;

[0010] A plurality of baffles are arranged in sequence along the water flow direction from the water inlet to the water outlet, and are perpendicular to the water flow direction; the baffles are arranged vertically or horizontally, so that the wastewater in the aeration oxidation tank flows from the water inlet to the water outlet in the form of an up-and-down serpentine or a horizontal serpentine;

[0011] Nano aeration tubes are evenly arranged at the bottom of the aeration oxidation pond.

[0012] Optionally, the water distributor of the manganese sand filter pool includes a water guide and several layers of water distribution rings below it, the water guide includes a water inlet pipe and a water guide pipe, one end of the water inlet pipe is connected to the water outlet, and the other end is connected to the middle of the water guide pipe, and openings are provided at both ends of the water guide pipe, and the two openings correspond to the grooves of the first layer of water distribution ring below the water guide pipe;

[0013] Several layers of water distribution rings are arranged up and down and concentrically. The inner diameter of the water distribution ring of the next layer is larger than the inner diameter of the water distribution ring of the previous layer. The water distribution ring is a hollow ring in the middle, and the ring is a sunken groove. Wastewater flows into the groove and then overflows into the groove of the water distribution ring of the next layer.

[0014] Further optionally, in the two adjacent layers of water distribution rings, the inner diameter of the lower water distribution ring is between the inner diameter and outer diameter of the upper water distribution ring, so that the inner edge of the circular groove of the upper water distribution ring is outside the inner edge of the circular groove of the lower water distribution ring, and the outer edge of the circular groove of the upper water distribution ring is between the inner and outer edges of the circular groove of the lower water distribution ring.

[0015] Optionally, the manganese sand filter layer covers the cross-section of the manganese sand filter pool, and support nets are provided above and below to support the corresponding manganese sand filter layer.

[0016] Optionally, a backwash air pipe is provided between the bottommost manganese sand filter layer and the backwash water pipe. The lower surface of the backwash air pipe is evenly and densely covered with air outlet holes. The air inlet end of the backwash air pipe passes through the side wall of the manganese sand filter tank and is connected to a backwash aerator, which is used to input gas into the manganese sand filter tank during backwashing.

[0017] Optionally, the manganese sand filter layer is filled with modified manganese sand, and the preparation method of the modified manganese sand comprises the following steps:

[0018] (1) After the original manganese sand is cleaned, it is dried;

[0019] (2) adding the manganese sand obtained in step (1) into a KMnO4 solution for immersion to obtain activated manganese sand;

[0020] (3) calcining the activated manganese sand and cooling it to obtain the modified manganese sand.

[0021] Optionally, in step (1), the manganese content of the original manganese sand is 35-45wt% and the particle size is 1-4mm; the original manganese sand can be rinsed with tap water and then dried in an oven at a drying temperature of 90-110°C.

[0022] Since the manganese sand particle size of the upper manganese sand filter layer is larger than that of the lower manganese sand filter layer, if two layers of manganese sand filter layers are set, the particle size of the original manganese sand corresponding to the modified manganese sand in the upper layer is 2-4mm, and the particle size of the original manganese sand corresponding to the lower layer is 1-2mm.

[0023] Optionally, in step (2), the concentration of the KMnO4 solution is 1-1.5% (W / V), and the mass volume ratio of manganese sand to KMnO4 solution is 1g:(10-20)ml;

[0024] The soaking time is 6-8h.

[0025] Optionally, in step (3), the calcination temperature is 200-250° C., the calcination time is 1-2 h, and the calcination can be carried out in a muffle furnace, followed by natural cooling.

[0026] Traditional filter layers generally adopt a natural stacking filling method. When wastewater passes through the filter layer from top to bottom, it will squeeze part of the filler, causing part of the filter layer to collapse after a long period of operation, and then squeeze the nearby filter layer, causing the filter layer to be disconnected, short-flow or dead zone, which is not conducive to the flow and treatment of wastewater. The present invention improves the manganese sand filter layer, can loosen the filter layer in the process of treating wastewater, improve the stacking state of the filter layer and the flow state of wastewater, and promote full contact between wastewater and modified manganese sand.

[0027] Optionally, a distance is left between the upper surface of the modified manganese sand filled in the manganese sand filter layer and the top support net; a plurality of inclined and mutually parallel rectifying nets are arranged inside the manganese sand filter layer, and each rectifying net runs through the manganese sand filter layer;

[0028] Guide rail grooves are respectively arranged on the side walls of the manganese sand filter tank corresponding to both sides of the manganese sand filter layer, and a plurality of guide rails are arranged on the side of the guide rail groove facing the manganese sand filter layer, and a slider is arranged in the guide rail corresponding to a manganese sand filter layer, and a first hydraulic cylinder is arranged above each guide rail groove, and a plurality of sliders in the corresponding guide rail groove are connected in parallel through a first hydraulic rod;

[0029] The top of the rectifying net is fixed on the supporting net corresponding to the top of the manganese sand filter layer, and the two ends of the bottom of the rectifying net are respectively connected to the sliders in the corresponding guide rails on the guide rail grooves on both sides, so that the bottom of the rectifying net can move up and down under the drive of the first hydraulic rod.

[0030] Further optionally, the modified manganese sand filled in the manganese sand filter layer is naturally and evenly laid on the bottom support net, and the accumulated volume of the modified manganese sand accounts for 75-85% of the total volume between the upper and lower support nets of the corresponding manganese sand filter layer.

[0031] Further optionally, the manganese sand filter pool is provided with guide rail grooves on the two side walls corresponding to the rectifier net on both sides, and the guide rail grooves are provided with several guide rails on the vertical lines corresponding to the bottoms of the rectifier nets, and the number of sliders arranged in each guide rail is the same as the number of corresponding manganese sand filter layers.

[0032] Further optionally, the two side edges of the rectifying net extend to the two sides of the manganese sand filter layer, and the two ends of the bottom of the rectifying net are respectively connected to the sliders in the corresponding guide rails, and the first hydraulic rod drives the bottom of the rectifying net to move up and down through the sliders.

[0033] Further optionally, the mesh aperture of the rectifying net is slightly larger than the average particle size of the modified manganese sand of the corresponding manganese sand filter layer; a sleeve is provided at the bottom of the rectifying net, the sleeve includes an inner tube and an outer tube, the two ends of the inner tube are used to connect the slider, the outer side of the outer tube is used to evenly fix the bottom edge of the rectifying net, and the length of the outer tube is slightly smaller than the inner tube;

[0034] A second hydraulic cylinder is arranged above the manganese sand filter tank, and all the outer pipes are connected in parallel through the second hydraulic rod, so as to drive the outer pipes to move horizontally left and right. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of a water treatment device for treating iron-manganese mine wastewater in Example 1;

[0036] Figure 2 It is a side structural schematic diagram of the water distributor of Example 3;

[0037] Figure 3 It is a schematic diagram of the top view of the water distributor of Example 3;

[0038] Figure 4 It is a schematic diagram of the three-dimensional structure of the rectifier network and the guide rail groove (omitting the manganese sand filler);

[0039] Figure 5 It is a schematic diagram of the three-dimensional structure of the rectifier network and the guide rail groove (the guide rail groove is omitted);

[0040] Figure 6 This is a structural diagram of the rectifier network.

[0041] In the accompanying drawings, 1-nano aerator, 2-aeration oxidation tank, 3-manganese sand filter tank, 4-water production tank, 5-nano aeration pipe, 6-water distributor, 7-backwash outlet, 8-manganese sand filter layer, 9-backwash water pipe, 10-water outlet, 11-air inlet pipe, 12-circulating water pipe, 13-water inlet, 14-water outlet, 15-baffle, 16-water distribution ring, 17-water inlet pipe, 18-water guide pipe, 19-support net, 20-backwash air pipe, 21-backwash aerator, 22-rectifier net, 23-guide rail groove, 24-guide rail, 25-slider, 26-first hydraulic cylinder, 27-first hydraulic rod, 28-inner tube, 29-outer tube, 30-second hydraulic cylinder, 31-second hydraulic rod, 32-first upper branch rod, 33-second upper branch rod, 34-support rod. DETAILED DESCRIPTION

[0042] The mine wastewater treated in the following embodiments and comparative examples is the effluent from the coagulation and sedimentation of mine water of a coal industry group, with an iron content of 15.12 mg / L, a manganese content of 1.03 mg / L, a filtration rate of the manganese sand filter layer of 8 m / h, and a thickness of the manganese sand filter layer of 900 mm. After the treatment of the manganese sand filter layer has been running for 10 hours, a backwash operation is performed, and the gas-water combined backwashing operation is performed for 20 minutes, completing one wastewater treatment and waiting for the next treatment.

[0043] Examples 1-4 and Comparative Example 1 use ordinary manganese sand on the market, purchased from Qiaodong Quartz Sand Factory in Jianping County. The manganese sand particle size of the upper manganese sand filter layer is 2-4mm, and the manganese sand particle size of the lower manganese sand filter layer is 1-2mm, and the manganese content is 40wt%.

[0044] Example 1

[0045] This embodiment provides a water treatment device for treating iron-manganese mine wastewater, such as Figure 1 As shown, it includes a nano aerator 1, an aeration oxidation pond 2, a manganese sand filter pond 3 and a water production tank 4 connected in sequence, wherein the nano aerator 1 is connected to a nano aeration pipe 5 at the bottom of the aeration oxidation pond 2 to provide nano gas to the aeration oxidation pond 2 to oxidize and treat mine wastewater;

[0046] The manganese sand filter pool 3 includes a water distributor 6, a backwash outlet 7, two layers of manganese sand filter layers 8, a backwash water pipe 9 and a water outlet 10 from top to bottom. The water outlet 14 of the aeration oxidation pool 2 is connected to the water distributor 6. After the wastewater after oxidation treatment passes through the manganese sand filter layer 8 after water distribution, it continues to be oxidized and then discharged into the water production tank 4 through the water outlet 10; the water outlet 10 is connected to the water production tank 4, and the backwash outlet 7 is connected to the water inlet 13 of the aeration oxidation pool 2;

[0047] The water production tank 4 is connected to the backwash water pipe 9 through a backwash pipeline, which is used for backwashing the manganese sand filter layer 8. The wastewater after backwashing is returned to the aeration oxidation tank 2 for treatment.

[0048] The air inlet of the nano aerator 1 is connected to the air inlet pipe 11, and the air inlet pipe 11 inputs air or oxygen. The liquid inlet of the nano aerator 1 is connected to the aeration oxidation pond 2 through the circulating water pipe 12. The wastewater in the aeration oxidation pond 2 is input into the nano aerator 1 as circulating water, and then mixed with the input air or oxygen, and input into the nano aeration pipe 5 of the aeration oxidation pond 2; the air outlet of the nano aerator 1 is connected to the nano aeration pipe 5.

[0049] The aeration oxidation pond 2 includes a water inlet 13, a circulating water outlet, a water outlet 14, three baffles 15 and a nano aeration tube 5. The water inlet 13 is arranged at the top of the aeration oxidation pond 2, the water outlet 14 is arranged on the side wall of the aeration oxidation pond 2 opposite to the water inlet 13, and the circulating water outlet is arranged below the water inlet 13 for connecting to the circulating water pipe 12.

[0050] The three baffles 15 are arranged in sequence along the water flow direction from the water inlet 13 to the water outlet 14, and are perpendicular to the water flow direction; the baffles 15 are arranged vertically or horizontally, so that the wastewater in the aeration oxidation tank 2 flows from the water inlet 13 to the water outlet 14 in the form of an up-and-down serpentine or a horizontal serpentine, thereby extending the residence time of the wastewater in the aeration oxidation tank 2 and improving the effect of oxidation treatment;

[0051] Nano aeration tubes 5 are evenly arranged at the bottom of the aeration oxidation pond 2 .

[0052] An overflow weir is provided at the water outlet 14 so that the effluent from the aeration oxidation pond 2 overflows through the overflow weir and flows out.

[0053] The baffle plate 15 is vertically arranged, and the two sides of the baffle plate 15 are respectively fixedly connected to the two side walls of the aeration and oxidation tank 2, and the top or bottom of the baffle plate 15 is respectively fixedly connected to the top wall or bottom surface of the aeration and oxidation tank 2;

[0054] Specifically, along the water flow direction in the aeration oxidation pond 2, the top of the previous baffle plate 15 is fixedly connected to the top wall of the aeration oxidation pond 2, and a gap is left between the bottom and the bottom surface of the aeration oxidation pond 2, and the bottom of the adjacent rear baffle plate 15 is fixedly connected to the bottom surface of the aeration oxidation pond 2, and a gap is left between the top and the top wall of the aeration oxidation pond 2. This arrangement is repeated, so that the inlet water of the aeration oxidation pond 2 passes through the gap between the baffle plate 15 and the top wall or bottom surface of the aeration oxidation pond 2, forming an up and down serpentine water flow direction.

[0055] The present invention adopts a nano-aerator 1 to mix the wastewater in the aeration oxidation pond 2 with air or oxygen to generate nano-bubbles, which are then input into the nano-aeration pipe 5 to uniformly provide nano-bubbles for the aeration oxidation pond 2 to oxidize the mine wastewater. The nano-bubbles have a certain oxidation capacity to convert Fe 2+ Oxidized to Fe(OH)3, Mn 2+ Oxidized into MnO2, thereby removing iron and manganese in mine wastewater. Nanobubbles have a small specific surface area, which can greatly shorten the oxidation reaction time. In addition, the two strong oxidizing free radicals (·OH and ·O) produced during the nanobubble rupture process can enhance the removal of organic matter and suspended solids in mine wastewater, reducing the clogging effect of organic pollutants on the manganese sand filter layer 8.

[0056] The mine wastewater is input into the aeration oxidation pond 2 from the water inlet 13. The baffle 15 allows the incoming wastewater to pass through the aeration oxidation pond 2 in a baffled manner, thereby increasing the flow length of the wastewater in the aeration oxidation pond 2, prolonging the contact time between the nanobubbles and the wastewater, and promoting the removal of Fe 2+ , Mn 2+ conversion.

[0057] The water outlet 14 of the aeration oxidation pond 2 is the water inlet 13 of the manganese sand filter pond 3, and the wastewater treated by the aeration oxidation pond 2 is input into the manganese sand filter pond 3 for further oxidation treatment.

[0058] The water distributor 6 is a traditional circular water distribution pipe, and the lower surface of the water distribution pipe is densely covered with water distribution holes.

[0059] The manganese sand filter layer 8 covers the cross section of the manganese sand filter pool 3, and is provided with support nets 19 above and below for supporting the corresponding manganese sand filter layer 8 to prevent the internal manganese sand from being lost. The support net 19 is a rigid net.

[0060] A backwash air pipe 20 is provided between the bottommost manganese sand filter layer 8 and the backwash water pipe 9. The lower surface of the backwash air pipe 20 is evenly and densely covered with air outlet holes. The air inlet end of the backwash air pipe 20 passes through the side wall of the manganese sand filter pool 3 and is connected to the backwash aerator 21, which is used to input gas into the manganese sand filter pool 3 during backwashing.

[0061] The upper surface of the backwash water pipe 9 is evenly and densely covered with water outlet holes, and the backwash water pipe 9 is connected to the water production tank 4 through a backwash pipeline and a water pump.

[0062] The manganese sand particle size of the upper manganese sand filter layer 8 is greater than the manganese sand particle size of the lower manganese sand filter layer 8.

[0063] The mine wastewater flows through several layers of manganese sand filter layers 8, and the dissolved divalent iron and divalent manganese are adsorbed or oxidized and then adsorbed, and the produced water is input into the water production tank 4 from the lower water production port 10. The iron and manganese compounds remain in the manganese sand filter layer 8, and the air and water combined backwashing of the backwash water pipe 9 and the backwash air pipe 20 is used to improve the backwashing efficiency and prevent the manganese sand filler from being blocked due to long-term operation. The water after backwashing is returned to the aeration oxidation tank 2 from the backwash outlet 7 for treatment.

[0064] Comparative Example 1

[0065] The water treatment device of this comparative example is the same as that of Example 1, except that no nano aerator and aeration oxidation tank are provided, and the mine wastewater directly enters the manganese sand filter tank for oxidation treatment, and the backwash outlet of the manganese sand filter tank is connected to the mine wastewater storage equipment.

[0066] Example 2

[0067] This embodiment provides a water treatment device for treating iron-manganese mine wastewater, which is the same as that of Embodiment 1, except that the baffle plate 15 is arranged horizontally, the top and bottom of the baffle plate 15 are respectively fixedly connected to the top wall and bottom surface of the aeration oxidation tank 2, one side of the baffle plate 15 is fixedly connected to one side wall of the aeration oxidation tank 2, and a gap is left between the other side and the other side wall of the aeration oxidation tank 2;

[0068] Along the water flow direction in the aeration oxidation pond 2, the left side of the previous baffle plate 15 is fixedly connected to the left side wall of the aeration oxidation pond 2, and a gap is left between the right side and the right side wall of the aeration oxidation pond 2. The right side of the adjacent rear baffle plate 15 is fixedly connected to the right side wall of the aeration oxidation pond 2, and a gap is left between the left side and the left side wall of the aeration oxidation pond 2. This arrangement is repeated so that the inlet water of the aeration oxidation pond 2 passes through the gap between the baffle plate 15 and the two side walls of the aeration oxidation pond 2, forming a horizontal serpentine water flow direction.

[0069] Example 3

[0070] This embodiment provides a water treatment device for treating iron-manganese mine wastewater, which is the same as that in embodiment 1, except that: Figure 2-Figure 3 As shown, the water distributor 6 of the manganese sand filter pool 3 includes a water guide and a three-layer water distribution ring 16 below it, the water guide includes a water inlet pipe 17 and a water guide pipe 18, one end of the water inlet pipe 17 is connected to the water outlet 14, and the other end is connected to the middle of the water guide pipe 18, and openings are provided at both ends of the water guide pipe 18, and the two openings correspond to the groove of the first layer of water distribution ring below the water guide pipe 18;

[0071] The three layers of water distribution rings 16 are arranged up and down and concentrically. The inner diameter of the lower layer of water distribution ring is larger than the inner diameter of the upper layer of water distribution ring. The water distribution ring 16 is a hollow ring in the middle, and the ring is a sunken groove. Wastewater flows into the groove and then overflows into the groove of the next layer of water distribution ring.

[0072] In the two adjacent layers of water distribution rings 16, the inner diameter of the lower water distribution ring is between the inner diameter and outer diameter of the upper water distribution ring, so that the inner edge of the circular groove of the upper water distribution ring is outside the inner edge of the circular groove of the lower water distribution ring, and the outer edge of the circular groove of the upper water distribution ring is between the inner and outer edges of the circular groove of the lower water distribution ring.

[0073] The water distributor 6 described in this embodiment has a first water distribution ring that receives the incoming water of the water pipe 18. When the incoming water fills the groove of the first water distribution ring, a part of the incoming water overflows from the inner edge of the first water distribution ring to the manganese sand filter layer 8 below, and another part of the incoming water overflows from the outer edge of the first water distribution ring to the second water distribution ring below; when the second water distribution ring is full, a part of the waste water overflows from the inner edge of the second water distribution ring to the manganese sand filter layer 8 below, and another part of the waste water overflows from the outer edge of the second water distribution ring to the third water distribution ring below, and so on and so forth. After passing through each layer of water distribution ring, a part of the water overflows to the water distribution ring of the next layer, so that the waste water can be evenly dispersed and can pass through the manganese sand filter layer 8 more evenly, thereby improving the filtering effect and reducing the direct impact of the incoming water on the manganese sand filter layer 8.

[0074] Example 4

[0075] This embodiment provides a water treatment device for treating iron-manganese mine wastewater, which is the same as that in embodiment 3, except that: Figure 4-Figure 6 As shown, there is a distance between the upper surface of the modified manganese sand filled in the manganese sand filter layer 8 and the top support net 19; four inclined and mutually parallel rectifying nets 22 are arranged inside the manganese sand filter layer 8, and each rectifying net 22 penetrates the manganese sand filter layer 8;

[0076] Guide rail grooves 23 are respectively provided on the side walls of the manganese sand filter pool 3 on both sides corresponding to the manganese sand filter layer 8, and four guide rails 24 are provided on the side of the guide rail groove 23 facing the manganese sand filter layer 8. A slider 25 is provided in the guide rail 24 corresponding to one manganese sand filter layer 8, and a first hydraulic cylinder 26 is provided above each guide rail groove 23, and the slider 25 in the corresponding guide rail groove 23 is connected in parallel through a first hydraulic rod 27;

[0077] The top of the rectifying net 22 is fixed on the supporting net 19 corresponding to the top of the manganese sand filter layer 8, and the two ends of the bottom of the rectifying net 22 are respectively connected to the sliders 25 in the corresponding guide rails 24 on the guide rail grooves 23 on both sides, so that the bottom of the rectifying net 22 can move up and down under the drive of the first hydraulic rod 27.

[0078] The modified manganese sand filled in the manganese sand filter layer 8 is naturally and evenly laid on the bottom support net 19, and the accumulated volume of the modified manganese sand accounts for 80% of the total volume between the upper and lower support nets 19 of the corresponding manganese sand filter layer 8.

[0079] The manganese sand filter pool 3 is provided with guide rail grooves 23 on the two side walls corresponding to the rectifying net 22, and the guide rail grooves 23 are provided with guide rails 24 on the vertical line corresponding to the bottom of the rectifying net 22. The number of sliders 25 arranged in each guide rail 24 is the same as the number of the corresponding manganese sand filter layer 8.

[0080] The two side edges of the rectifying net 22 extend to the two sides of the manganese sand filter layer 8, and the two ends of the bottom of the rectifying net 22 are respectively connected to the sliders 25 in the corresponding guide rails 24. The first hydraulic rod 27 drives the bottom of the rectifying net 22 to move up and down through the sliders 25, so that the rectifying net 22 drives the modified manganese sand above itself to move up and down, thereby loosening the manganese sand filter layer 8, allowing the manganese sand to naturally settle and accumulate again under the action of gravity, thereby improving the accumulation of the manganese sand filter layer 8.

[0081] The mesh aperture of the rectifying net 22 is slightly larger than the average particle size of the modified manganese sand of the corresponding manganese sand filter layer 8; a sleeve is provided at the bottom of the rectifying net 22, and the sleeve includes an inner tube 28 and an outer tube 29, and the two ends of the inner tube 28 are used to connect the slider 25, and the outer side of the outer tube 29 is used to evenly fix the bottom edge of the rectifying net 22, and the length of the outer tube 29 is slightly smaller than the inner tube 28;

[0082] A second hydraulic cylinder 30 is provided above the manganese sand filter pool 3, and all the outer tubes 29 are connected in parallel through the second hydraulic rod 31, driving the outer tubes 29 to move horizontally left and right, so that the rectifying net 22 can vibrate left and right while moving up and down, forming a vibration screening effect, and screening is performed in the process of driving the manganese sand to move upward, so that most of the manganese sand passes through the rectifying net 22 and falls down, achieving the purpose of re-depositing, and finally the remaining manganese sand on the rectifying net 22 can also fall back into the manganese sand filter layer 8 when the rectifying net 22 moves downward.

[0083] Specifically, the manganese sand filter pool 3 is provided with two layers of manganese sand filter layers 8, each layer having a thickness of 900 mm, the particle size of the modified manganese sand in the upper layer being 2-4 mm, and the particle size of the modified manganese sand in the lower layer being 1-2 mm. Four inclined rectifier nets 22 parallel to each other are provided in each manganese sand filter layer 8, and the angle between the rectifier net 22 and the vertical direction is 35-65°. In two adjacent rectifier nets 22, the top of the previous rectifier net 22 and the bottom of the next rectifier net 22 are on the same vertical straight line, so that the cross-sectional area of ​​several rectifier nets 22 is equal to the cross-sectional area of ​​the manganese sand filter layer 8, and the entire manganese sand filter layer 8 can be fully rectified. The top of the rectifier net 22 is fixed on the upper support net 19 of the corresponding manganese sand filter layer 8, the bottom of the rectifier net 22 is fixed on the outer side of the outer tube 29 of the corresponding casing, and the rectifier net 22 is flat and stretched. The two guide rail grooves 23 are detachably mounted on the left and right inner sides of the manganese sand filter pool 3 without destroying the original manganese sand filter pool 3; the two sides of the rectifying net 22 correspond to the left and right inner sides of the manganese sand filter pool 3 respectively. Four vertical guide rails 24 recessed into the guide rail groove 23 are provided on the side wall of the guide rail groove 23 facing the manganese sand filter layer 8, and the position of each guide rail 24 corresponds to the position of a sleeve at the bottom of the rectifying net 22, so that the two ends of the inner tube 28 of the sleeve are respectively connected to the two sliders 25 in the corresponding guide rails 24 on the two guide rail grooves 23. Since the number of rectifying nets 22 in the upper and lower manganese sand filter layers 8 is the same and the positions correspond to each other, each guide rail 24 is provided with two upper and lower sliders 25 for connecting the rectifying nets 22 at corresponding positions of the upper and lower manganese sand filter layers 8. A first hydraulic cylinder 26 is provided above the middle of each guide groove 23. The telescopic end of the first hydraulic cylinder 26 is connected to the top of the first hydraulic rod 27. The bottom of the first hydraulic rod 27 is connected in parallel with the slider 25 of the guide rail 24 in the corresponding guide groove 23. Since two upper and lower sliders 25 are provided in each guide rail 24, the bottom of the first hydraulic rod 27 is connected in parallel with the slider 25 of the upper manganese sand filter layer 8 through a plurality of vertical first upper sub-rods 32. A first lower sub-rod is connected below each first upper sub-rod 32, and the slider 25 of the corresponding lower manganese sand filter layer 8 is connected through the first lower sub-rod, so that all the sliders 25 in the corresponding guide groove 23 are driven to move up and down synchronously through the first hydraulic rod 27. The two first hydraulic cylinders 26 run synchronously, which can drive the bottom of all rectifier nets 22 to move up and down synchronously. A horizontal support rod 34 is connected between the two first hydraulic rods 27, and a second hydraulic cylinder 30 is provided on the support rod 34, so that the second hydraulic cylinder 30 moves synchronously with the first hydraulic rod 27.The telescopic end of the second hydraulic cylinder 30 is horizontally connected to the top of the second hydraulic rod 31. The bottom of the second hydraulic rod 31 is connected in parallel to the outer tube 29 of the sleeve of the upper manganese sand filter layer 8 through a plurality of vertical second upper branch rods 33 (the two ends of the outer tube 29 or any position between the two ends can be used). A second lower branch rod is connected below each second upper branch rod 33, and the outer tube 29 of the sleeve of the corresponding lower manganese sand filter layer 8 is connected through the second lower branch rod, so that all the outer tubes 29 are driven to move left and right synchronously through the second hydraulic rod 31. Since the length of the outer tube 29 is slightly smaller than the inner tube 28, all the rectifying nets 22 have space to move left and right. Through the above arrangement, the first hydraulic cylinder 26 controls the bottom of the rectifying net 22 to move up and down, and can also move left and right under the control of the second hydraulic cylinder 30, forming a screening movement form of up and down, left and right, driving the modified manganese sand on the rectifying net 22 to move up and down, left and right, and fall through the mesh, so as to achieve the purpose of loosening and reorganizing the manganese sand filter layer 8, and improve the short flow, interruption and dead zone of the manganese sand filter layer 8.

[0084] After the manganese sand filter layer 8 has been treated for 50 minutes, the first hydraulic cylinder 26 controls the bottom of the rectifying net 22 to move up and down at a frequency of 8 up and down / min, and the second hydraulic cylinder 30 controls the rectifying net 22 to move left and right at a frequency of about 30 back and forth / min. The rectifying net 22 stops moving after 10 minutes of treatment. When the rectifying net 22 moves, the treatment process is not paused; this operation is repeated until the rectifying net 22 has been moved for 10 times, and then a backwash operation is performed, and the air-water combined backwashing is 20 minutes, that is, one wastewater treatment is completed, and waiting for the next treatment.

[0085] Table 1 Comparison of treatment effects of Examples 1-4 and Comparative Example 1

[0086] Iron content of produced water (mg / L) Manganese content of produced water (mg / L) Example 1 0.4 0.3 Example 2 0.5 0.4 Example 3 0.3 0.2 Example 4 0.2 0.1 Comparative Example 1 0.9 0.7

[0087] As can be seen from the above table, the water treatment device for treating iron-manganese mine wastewater proposed in the present invention uses the nano aerator 1 to provide nano bubbles for the aeration oxidation tank to oxidize the mine wastewater, and then combines it with the manganese sand filter tank for further treatment. The water distributor and the rectifier net used in the manganese sand filter tank improve the water flow of the manganese sand filter layer, so that the wastewater is fully in contact with the manganese sand, thereby improving the treatment effect.

[0088] Preparation Example 1

[0089] The preparation method of the modified manganese sand described in this preparation example comprises the following steps:

[0090] (1) Rinse the original manganese sand with tap water and dry it in an oven for 2 h at a drying temperature of 110°C;

[0091] The manganese content of the original manganese sand is 45wt% and the particle size is 2-4mm;

[0092] (2) adding the manganese sand obtained in step (1) into a KMnO4 solution having a concentration of 1% (W / V) and soaking for 8 hours to obtain activated manganese sand;

[0093] (3) The activated manganese sand is calcined in a muffle furnace at 200° C. for 1 h, taken out and naturally cooled to obtain the modified manganese sand I.

[0094] Preparation Example 2

[0095] The preparation method of the modified manganese sand described in this preparation example comprises the following steps:

[0096] (1) Rinse the original manganese sand with tap water and dry it in an oven for 2 h at a drying temperature of 110°C;

[0097] The manganese content of the original manganese sand is 45wt% and the particle size is 1-2mm;

[0098] (2) adding the manganese sand obtained in step (1) into a KMnO4 solution having a concentration of 1% (W / V) and soaking for 8 hours to obtain activated manganese sand;

[0099] (3) calcining the activated manganese sand in a muffle furnace at 200° C. for 1 h, taking it out and cooling it naturally to obtain the modified manganese sand II.

[0100] Embodiment 5-8

[0101] The modified manganese sand I obtained in Preparation Example 1 was used to replace the corresponding large-particle manganese sand in the upper layer of Examples 1-4, and the modified manganese sand II obtained in Preparation Example 2 was used to replace the corresponding small-particle manganese sand in the lower layer of Examples 1-4.

[0102] Table 2 Comparison of treatment effects of Examples 5-8

[0103] Iron content of produced water (mg / L) Manganese content of produced water (mg / L) Example 5 0.21 0.10 Example 6 0.32 0.23 Example 7 0.16 0.06 Example 8 0.07 0.01

[0104] As can be seen from the above table, the equipment improvement of the present invention combined with the modified manganese sand further reduces the iron content and manganese content of the produced water.

Claims

1. A water treatment device for treating iron-manganese mine wastewater, characterized in that: It includes a nano aerator, an aeration oxidation tank, a manganese sand filter tank and a water production tank connected in sequence, wherein the nano aerator is connected to a nano aeration pipe at the bottom of the aeration oxidation tank to provide nano gas to the aeration oxidation tank to oxidize and treat mine wastewater; The manganese sand filter pool includes a water distributor, a backwash outlet, several layers of manganese sand filter layers, a backwash water pipe and a water outlet from top to bottom. The outlet of the aeration oxidation tank is connected to the water distributor. After the wastewater after oxidation treatment passes through the manganese sand filter layer, it is discharged into the water production tank through the water outlet. The water outlet is connected to the water production tank, and the backwash outlet is connected to the water inlet of the aeration oxidation tank; The water production tank is connected to the backwash water pipe through the backwash pipe, which is used to backwash the manganese sand filter layer, and the wastewater after backwashing is returned to the aeration oxidation tank for treatment; The manganese sand filter layer covers the cross section of the manganese sand filter pool, and is provided with support nets above and below for supporting the corresponding manganese sand filter layer; A backwash air pipe is provided between the bottom manganese sand filter layer and the backwash water pipe. The lower surface of the backwash air pipe is evenly and densely covered with air outlet holes. The air inlet end of the backwash air pipe passes through the side wall of the manganese sand filter tank and is connected to the backwash aerator to input gas into the manganese sand filter tank during backwashing. The manganese sand filter layer is filled with modified manganese sand, and the preparation method of the modified manganese sand comprises the following steps: (1) After the original manganese sand is cleaned, it is dried; (2) adding the manganese sand obtained in step (1) into a KMnO 4 solution for immersion to obtain activated manganese sand; (3) calcining the activated manganese sand and cooling it to obtain the modified manganese sand; There is a distance between the upper surface of the modified manganese sand filled in the manganese sand filter layer and the top support net; a plurality of inclined and mutually parallel rectifying nets are arranged inside the manganese sand filter layer, and each rectifying net runs through the manganese sand filter layer; Guide rail grooves are respectively arranged on the side walls of the manganese sand filter tank corresponding to both sides of the manganese sand filter layer, and a plurality of guide rails are arranged on the side of the guide rail groove facing the manganese sand filter layer, and a slider is arranged in the guide rail corresponding to a manganese sand filter layer, and a first hydraulic cylinder is arranged above each guide rail groove, and a plurality of sliders in the corresponding guide rail groove are connected in parallel through a first hydraulic rod; The top of the rectifying net is fixed on the supporting net corresponding to the top of the manganese sand filter layer, and the two ends of the bottom of the rectifying net are respectively connected to the sliders in the corresponding guide rails on the guide rail grooves on both sides, so that the bottom of the rectifying net can move up and down under the drive of the first hydraulic rod; The manganese sand filter pool is provided with guide rail grooves on the two side walls corresponding to the two sides of the rectifying net, and a plurality of guide rails are provided on the vertical lines corresponding to the bottoms of the rectifying nets. The number of sliders arranged in each guide rail is the same as the number of corresponding manganese sand filter layers.

2. The water treatment device for treating iron-manganese mine wastewater according to claim 1, characterized in that: The aeration oxidation pond comprises a water inlet, a circulating water outlet, a water outlet, a plurality of baffles and a nano aeration tube, wherein the water inlet is arranged at the top of the aeration oxidation pond, the water outlet is arranged on the side wall of the aeration oxidation pond opposite to the water inlet, and the circulating water outlet is arranged below the water inlet for connecting to the circulating water pipe; A plurality of baffles are arranged in sequence and at intervals along the water flow direction from the water inlet to the water outlet, and are perpendicular to the water flow direction; the baffles are arranged vertically or horizontally, so that the wastewater in the aeration oxidation tank flows from the water inlet to the water outlet in the form of an up-and-down serpentine or a horizontal serpentine; nano aeration tubes are evenly arranged at the bottom of the aeration oxidation tank.

3. The water treatment device for treating iron-manganese mine wastewater according to claim 2, characterized in that: The air inlet of the nano aerator is connected to the air inlet pipe, which inputs air or oxygen. The liquid inlet of the nano aerator is connected to the aeration oxidation tank through a circulating water pipe. The air outlet of the nano aerator is connected to the nano aeration pipe.

4. The water treatment device for treating iron-manganese mine wastewater according to claim 2, characterized in that: The water distributor of the manganese sand filter pool includes a water guide and several layers of water distribution rings below it, the water guide includes a water inlet pipe and a water guide pipe, one end of the water inlet pipe is connected to the water outlet, and the other end is connected to the middle of the water guide pipe, and openings are provided at both ends of the water guide pipe, and the two openings correspond to the grooves of the first layer of water distribution ring below the water guide pipe; Several layers of water distribution rings are arranged up and down and concentrically. The inner diameter of the water distribution ring of the next layer is larger than the inner diameter of the water distribution ring of the previous layer. The water distribution ring is a hollow ring in the middle, and the ring is a sunken groove. Wastewater flows into the groove and then overflows into the groove of the water distribution ring of the next layer.

5. The water treatment device for treating iron-manganese mine wastewater according to claim 4, characterized in that: In the two adjacent layers of water distribution rings, the inner diameter of the lower water distribution ring is between the inner diameter and outer diameter of the upper water distribution ring, so that the inner edge of the circular groove of the upper water distribution ring is outside the inner edge of the circular groove of the lower water distribution ring, and the outer edge of the circular groove of the upper water distribution ring is between the inner and outer edges of the circular groove of the lower water distribution ring.

6. The water treatment device for treating iron-manganese mine wastewater according to claim 1, characterized in that: The mesh aperture of the rectifying net is slightly larger than the average particle size of the modified manganese sand of the corresponding manganese sand filter layer; a sleeve is provided at the bottom of the rectifying net, the sleeve includes an inner tube and an outer tube, the two ends of the inner tube are used to connect the slider, the outer side of the outer tube is used to evenly fix the bottom edge of the rectifying net, and the length of the outer tube is slightly smaller than the length of the inner tube; A second hydraulic cylinder is arranged above the manganese sand filter tank, and all the outer pipes are connected in parallel through the second hydraulic rod, so as to drive the outer pipes to move horizontally left and right.

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