Equipment and process for treating perchlorate wastewater by biological reduction and synergistic adsorption

Abstract

This invention discloses an equipment and process for the bioreduction-synergistic adsorption treatment of perchlorate wastewater, comprising a flocculation pretreatment system, an anaerobic bioreduction system, and a deep adsorption treatment system. The flocculation pretreatment system includes a flocculation tank, which is divided into a mixing zone, a baffle zone, a sedimentation zone, and a temporary storage zone. An inlet pipe is provided on one side of the mixing zone, and an outlet pipe is provided on one side of the temporary storage zone. The outlet pipe is connected to the anaerobic microbial reduction system. The bioreduction-synergistic adsorption treatment process is used to treat ClO4... – The removal rate is extremely high. The biological reduction process can effectively degrade perchlorate and convert it into chloride or chloride ions with lower toxicity, thereby reducing the toxicity of wastewater. Compared with traditional chemical methods, the biological reduction degradation process is more thorough and has lower treatment costs.

Description

Technical Field

[0001] The invention belongs to the technical field of perchlorate wastewater treatment, and specifically relates to equipment and a process for treating perchlorate wastewater with biological reduction and synergistic adsorption. Background Art

[0002] Perchlorate (ClO4 - ) is an emerging persistent pollutant. In addition to natural sources, most of it comes from artificial synthesis. Perchlorate products are widely used in military industry, aerospace, fireworks manufacturing and other fields.

[0003] At present, the more mature perchlorate removal methods can be divided into physical, chemical and biological methods. Among them, the ion exchange adsorption method, membrane filtration method, catalytic reduction method and biological reduction method have better removal effects. However, various treatment technologies have disadvantages. For example, the regeneration of the resin in the ion exchange method produces a large amount of waste liquid, which requires secondary treatment, resulting in increased costs; the membrane of the membrane filtration method is easy to clog, the backwashing operation is troublesome, and the operating cost is high; the preparation method of the catalyst in the catalytic reduction method is complicated and expensive; the conditions required for the biological reduction degradation process need to be strictly controlled, and the biological method has the risk of instability. In view of the above problems, it is necessary to conduct a systematic study on the perchlorate wastewater treatment process to obtain a simple, efficient and low-cost process, which is of great significance for completely solving the perchlorate pollution problem.

[0004] The existing perchlorate wastewater treatment method requires flocculation and sedimentation of the water body in the early stage of perchlorate wastewater treatment to remove a large amount of suspended matter and some interfering ions. Flocculation and sedimentation require a certain amount of time, and the output of the upper clarified liquid and the formation of the suspended matter sedimentation sludge have different cycles. It cannot be guaranteed that the sludge at the bottom of the pool can be treated in time while the upper clarified liquid is continuously pumped. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention aims to provide a device and process for treating perchlorate wastewater by biological reduction and synergistic adsorption.

[0006] The technical solution adopted by the present invention is:

[0007] A device for treating perchlorate wastewater by biological reduction and coordinated adsorption comprises a flocculation pretreatment system, an anaerobic microbial reduction system and a deep adsorption treatment system. The flocculation pretreatment system comprises a flocculation tank, and the flocculation system is divided into a mixing zone, a folding plate zone, a sedimentation zone and a temporary storage zone; a water inlet pipe is arranged on one side of the mixing zone, and a water outlet pipe is arranged on one side of the temporary storage zone, and the water outlet pipe is connected to the anaerobic microbial reduction system; a fixed plate and a control plate are arranged in the sedimentation zone, the fixed plate is located at the upper part of the flocculation tank, the fixed plate is fixedly connected to the inner side wall of the flocculation tank, an installation box is arranged between the fixed plate and the temporary storage zone, a sludge pipe is arranged on one side of the installation box, the control plate is located at the lower part of the flocculation tank, a connecting shaft is fixedly arranged at both ends of the control plate, the connecting shaft is rotatably connected to the inner side wall of the flocculation tank, a control motor is fixedly arranged on the outer side wall of the flocculation tank, the output shaft of the control motor passes through the side wall of the flocculation tank, and the output shaft of the control motor is fixedly connected to the connecting shaft.

[0008] As a preferred embodiment of the present invention, the mixing zone and the folding plate zone are separated by a partition plate, the partition plate is fixedly connected to the inner wall of the flocculation tank, the folding plate zone is communicated with the lower part of the mixing zone, a dosing tank is provided in the mixing zone, a fixing frame is fixedly provided on the side of the dosing tank, and the fixing frame is fixedly connected to the inner wall of the flocculation tank and the partition plate.

[0009] As a preferred embodiment of the present invention, a mounting plate is respectively provided on both sides of the dosing tank, and the mounting plate is fixedly connected to the flocculation tank and the partition plate. A driving motor is fixedly provided on one side of the mounting plate, and the output shaft of the driving motor passes through the mounting plate. A rotating rod is rotatably provided on the side of the mounting plate away from the driving motor, and the rotating rod is fixedly connected to the output shaft of the driving motor. A plurality of stirring plates are provided on the circumferential side of the rotating rod.

[0010] As a preferred embodiment of the present invention, the folded plate zone is located between the mixing zone and the sedimentation zone, the upper part of the folded plate zone is connected to the sedimentation zone, a plurality of folded plates and flat plates are provided in the folded plate zone, the folded plates and the flat plates form a different folded plate zone, a same folded plate zone and a flat plate partition zone, the water flows through the different folded plate zone, the same folded plate zone and the flat plate partition zone in sequence, and the suspended matter therein produces flocculation.

[0011] As a preferred embodiment of the present invention, the temporary storage area is located on a side of the sedimentation area away from the folding plate area, the temporary storage area and the sedimentation area are separated by an overflow plate, the overflow plate is fixedly connected to the inner wall of the flocculation tank, the temporary storage area is connected to the upper part of the sedimentation area, and a plurality of overflow ports are provided on the top of the overflow plate.

[0012] As a preferred embodiment of the present invention, a return pipe is provided on one side of the flocculation tank, one end of the return pipe is connected to the temporary storage area, a plurality of spoiler pipes are fixedly provided on the other end of the return pipe, the spoiler pipes are connected to the mixing area, a return pump is provided on the return pipe, and a control valve is detachably installed on the spoiler pipe.

[0013] As a preferred embodiment of the present invention, the installation box is detachably mounted on a load-bearing beam, the load-bearing beam is fixedly connected to the flocculation tank, and a lifting pipe is provided on one side of the installation box, and the lifting pipe is connected to the sludge pipe.

[0014] As a preferred embodiment of the present invention, a lining is provided at one end of the lifting pipe away from the installation box, a plurality of suction pipes are provided on both sides of the lining, the suction pipes are connected to the lifting pipe, and the lining is fixedly connected to the inner wall of the flocculation tank.

[0015] As a preferred embodiment of the present invention, a plurality of water holes are respectively provided on the fixed plate and the control plate, a plurality of guide grooves are respectively fixedly provided on one side of the fixed plate and the control plate close to the temporary storage area, and the water holes and the guide grooves are staggeredly distributed.

[0016] A process for treating perchlorate wastewater by biological reduction and synergistic adsorption comprises the following steps:

[0017] S1, flocculation and sedimentation, adding a flocculation precipitant to the flocculation tank to remove suspended matter and interfering ions in the water body to obtain wastewater sludge and upper clarified liquid;

[0018] S2. Microbial reduction. The anaerobic microbial reduction system includes a UASB reactor. The wastewater sludge output from the sludge pipe is used to make a sludge bed of the UASB reactor. The upper clarified liquid of the wastewater is continuously pumped into the UASB reactor. Under anaerobic conditions, ClO4 in the wastewater is reduced by perchlorate-reducing bacteria. – Convert low-valent chloride ions;

[0019] S3, deep adsorption treatment, the water enters the ion exchange column, passes through the quartz sand layer and the resin layer in turn, and absorbs the residual ClO4 in the water through ion exchange – ;

[0020] S4, desorption and regeneration. After the resin and quartz sand in the ion exchange column are saturated with adsorption, the backwash pump is started to extract the regeneration liquid to desorb and regenerate the exchange column, so as to reuse the material.

[0021] As a preferred embodiment of the present invention, the microbial reduction system includes a UASB reactor, the sludge pipe transports sludge to the sludge bed of the UASB reactor, the outlet pipe continuously pumps the supernatant of the wastewater into the UASB reactor, and inside the UASB reactor, under anaerobic conditions, ClO4 in the wastewater is reduced by perchlorate-reducing bacteria. – Convert low-valent chloride ions; after the wastewater is reduced by the biological method, it enters the ion exchange column, passes through the quartz sand layer and the resin layer in turn, and absorbs the residual ClO4 in the water through ion exchange. – .

[0022] The beneficial effects of the present invention are:

[0023] (1) Treatment process based on biological reduction and synergistic adsorption for ClO4 – The removal rate is extremely high, reaching more than 99%, and the ClO4- concentration in the effluent can be reduced to below 0.7 mg / L, which is lower than the emission limit of the "Industrial Wastewater Perchlorate Pollutant Emission Standard";

[0024] (2) The biological reduction process can effectively degrade perchlorate and convert it into less toxic chloride or chloride ions, thus reducing the toxicity of wastewater. Compared with traditional chemical methods, the biological reduction process is usually more environmentally friendly and has lower treatment costs;

[0025] (3) The bioreduction process combines autotrophy and heterotrophy, reducing the addition of carbon sources;

[0026] (4) Post-adsorption treatment can further remove residual perchlorate and improve wastewater treatment efficiency. Compared with common resin adsorption materials, the modified ion exchange resin of the present invention has the characteristics of small particle size, large specific surface area, large adsorption capacity, and easy regeneration. After the resin is saturated with adsorption, it can be regenerated with only a small amount of low-concentration strong alkaline solution or salt water. The resin can be recycled, which is beneficial to reduce treatment costs.

[0027] (5) The method has wide applicability and is well adaptable to the treatment of perchlorate wastewater with different concentration gradients and different scales, and is not affected by other ions in the wastewater (such as SO4 2- 、NO3 - etc.) impact;

[0028] (6) It overcomes the defects of the two processes. The combination of ion exchange resin and traditional water treatment processes such as coagulation can achieve effective complementarity in pollutant removal, while reducing the dosage of water treatment agents such as coagulants and saving costs;

[0029] (7) During the flocculation and sedimentation stage, the stirring plate is used to accelerate the mixing of the flocculation and sedimentation agent and the water body. At the same time, the return wastewater in the temporary storage area is used to compensate for the loss of water flow rate in the mixing area without affecting the efficiency of the water body passing through the folding plate area normally;

[0030] (8) The sludge produced in the flocculation tank is used to make the UASB reactor sludge bed. The large suspended sediment and the small suspended sediment are separated by the fixed plate and the control plate. The small suspended sediment is continuously pumped out and the large suspended sediment is periodically pumped out to avoid the long-term accumulation of sludge and reduce the cost of sludge treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0032] Figure 1 It is a schematic diagram of the structure of the flocculation pretreatment system of the present invention;

[0033] Figure 2 The present invention Figure 1 A schematic diagram of a top view structure;

[0034] Figure 3 The present invention Figure 2 Schematic diagram of the AA direction structure;

[0035] Figure 4 The present invention Figure 1 Schematic diagram of the internal structure. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0038] Combine the following Figure 1-4The specific implementation mode of the present invention is described. A device for treating perchlorate wastewater by biological reduction and coordinated adsorption includes a flocculation pretreatment system, an anaerobic microbial reduction system and an ion exchange column. The flocculation pretreatment system includes a flocculation tank 11, and the flocculation tank 11 is divided into a mixing zone 26, a folding plate zone 15, a sedimentation zone 45 and a temporary storage zone 28; a water inlet pipe 14 is provided on one side of the mixing zone 26, and a water outlet pipe 22 is provided on one side of the temporary storage zone 28, and the water outlet pipe 22 is connected to the anaerobic microbial reduction system; a fixed plate 17 and a control plate 29 are provided in the sedimentation zone 45, and the fixed plate 17 is located at the upper part of the flocculation tank 11. The fixed plate 17 is fixedly connected to the inner wall of the flocculation tank 11, and an installation box 18 is provided between the fixed plate 17 and the temporary storage area 28. A sludge pipe 16 is provided on one side of the installation box 18. The control panel 29 is located at the lower part of the flocculation tank 11. A connecting shaft 44 is fixedly provided at both ends of the control panel 29, and the connecting shaft 44 is rotatably connected to the inner wall of the flocculation tank 11. A control motor 23 is fixedly provided on the outer wall of the flocculation tank 11, and the output shaft of the control motor 23 passes through the side wall of the flocculation tank 11, and the output shaft of the control motor 23 is fixedly connected to the connecting shaft 44. The fixed plate 17 and the control plate 29 are used to distinguish between large-particle suspended sediment and small-particle suspended sediment in the sedimentation area. Small-particle suspended sediment is easy to float with the water flow, easy to escape through overflow into the temporary storage area 28, and easy to float around to the corners of the bottom of the pool, adhere and accumulate, and need to be treated in time. Therefore, the small-particle suspended sediment is distinguished separately and is sucked and treated after sedimentation; while the large-particle suspended sediment is relatively stable and will not float around. The cost of frequent treatment is high, so it is distinguished and periodically treated to reduce the cost of sludge treatment.

[0039] Advantageously, the mixing zone 26 and the folding plate zone 15 are separated by a partition plate 35, the partition plate 35 is fixedly connected to the inner side wall of the flocculation tank 11, the folding plate zone 15 is connected to the lower part of the mixing zone 26, a dosing tank 13 is provided in the mixing zone 26, a fixing frame 40 is fixedly provided on the side of the dosing tank 13, and the fixing frame 40 is fixedly connected to the inner side wall of the flocculation tank 11 and the partition plate 35. The liquid level of the mixing zone 26 is higher than that of other zones, and the water body is forced to flow in a directional manner by relying on the pressure of the water level difference.

[0040] Advantageously, a mounting plate 37 is provided on both sides of the dosing tank 13, the mounting plate 37 is fixedly connected to the flocculation tank 11 and the partition plate 35, a driving motor 36 is fixedly provided on one side of the mounting plate 37, the output shaft of the driving motor 36 passes through the mounting plate 37, a rotating rod 39 is provided on the side of the mounting plate 37 away from the driving motor 36, the rotating rod 39 is fixedly connected to the output shaft of the driving motor 36, and a plurality of stirring plates 38 are provided around the rotating rod 39. The flocculation precipitant is mixed quickly by stirring the water body, thereby accelerating the generation of flocculent suspended matter.

[0041] Advantageously, the folded plate area 15 is located between the mixing area 26 and the settling area 45, the upper part of the folded plate area 15 is connected to the settling area 45, a plurality of folded plates and flat plates are arranged in the folded plate area 15, the folded plates and the flat plates form a different folded plate area 32, a same folded plate area 33 and a flat plate partition area 34, the water flows sequentially through the different folded plate area 32, the same folded plate area 33 and the flat plate partition area 34, and the suspended matter therein is flocculated. The folded plate area 15 helps the suspended matter to flocculate quickly.

[0042] Advantageously, the temporary storage area 28 is located on a side of the sedimentation area 45 away from the folding plate area 15, the temporary storage area 28 and the sedimentation area 45 are separated by an overflow plate 21, the overflow plate 21 is fixedly connected to the inner wall of the flocculation tank 11, the temporary storage area 28 is connected to the upper part of the sedimentation area 45, and the top of the overflow plate 21 is provided with a plurality of overflow ports 20. The suspended solids sediment sludge is not treated for a long time and accumulates at the junction of the overflow plate 21 and the bottom of the tank.

[0043] Advantageously, a return pipe 12 is provided on one side of the flocculation tank 11, one end of the return pipe 12 is connected to the temporary storage area 28, and a plurality of spoiler pipes 25 are fixedly provided on the other end of the return pipe 12, and the spoiler pipes 25 are connected to the mixing area 26. A return pump 27 is provided on the return pipe 12, and a control valve 24 is detachably installed on the spoiler pipe 25. The control valve 24 can control the flow rate of each spoiler pipe 25 individually, and the spoiler pipe 25 can compensate for the flow rate lost by stirring the water body in the mixing area 26; and the provision of the temporary storage area 28 does not affect the continuous pumping of the upper clarified liquid into the UASB reactor even if the flocculation sedimentation has periodic output, and the output of the upper clarified liquid is always higher than the demand of the UASB reactor, and the excess upper clarified liquid output can be periodically refluxed.

[0044] Advantageously, the installation box 18 is detachably mounted on a load-bearing beam 19 , and the load-bearing beam 19 is fixedly connected to the flocculation tank 11 . A lifting pipe 31 is provided on one side of the installation box 18 , and the lifting pipe 31 is connected to the sludge pipe 16 .

[0045] Advantageously, a liner 30 is provided at one end of the lifting pipe 31 away from the installation box 18, and a plurality of suction pipes 43 are provided on both sides of the liner 30, the suction pipes 43 are communicated with the lifting pipe 31, and the liner 30 is fixedly connected to the inner wall of the flocculation tank 11. The lifting pipe 31 and the suction pipe are distributed at the small particle suspension sedimentation position of the entire sedimentation area 45, so as to facilitate the suction of the small particle suspension sedimentation at any time.

[0046] Advantageously, the fixed plate 17 and the control plate 29 are respectively provided with a plurality of water holes 41, and the fixed plate 17 and the control plate 29 are respectively fixedly provided with a plurality of guide grooves 42 on one side close to the temporary storage area 28, and the water holes 41 and the guide grooves 42 are staggered. The actual aperture of the water holes 41 is very small, and the actual distribution of the guide grooves 42 is also very dense. The examples given in the attached drawings are only for reference. The cooperation of the two allows large suspended particles to be intercepted, while guiding small suspended particles to settle quickly.

[0047] A process for treating perchlorate wastewater by biological reduction and synergistic adsorption comprises the following steps:

[0048] S1, flocculation and sedimentation, adding a flocculation precipitant to the flocculation tank 11 to remove suspended matter and interfering ions in the water body to obtain wastewater sludge and upper clarified liquid;

[0049] S2, microbial reduction, the anaerobic microbial reduction system includes a UASB reactor, the wastewater sludge output from the sludge pipe 16 is used to make the sludge bed of the UASB reactor, the upper clarified liquid of the wastewater is continuously pumped into the UASB reactor, and the ClO4 in the wastewater is reduced by perchlorate-reducing bacteria under anaerobic conditions. – Convert low-valent chloride ions;

[0050] S3, deep adsorption treatment, the water enters the ion exchange column, passes through the quartz sand layer and the resin layer in turn, and absorbs the residual ClO4 in the water through ion exchange – ;

[0051] S4, desorption and regeneration. After the resin and quartz sand in the ion exchange column are saturated with adsorption, the backwash pump is started to extract the regeneration liquid to desorb and regenerate the exchange column, so as to reuse the material.

[0052] Working principle of the present invention:

[0053] First, a flocculant is added to the dosing tank 13 to flocculate and precipitate the wastewater containing perchlorate, remove a large amount of suspended matter and some interfering ions in the water body, and obtain an upper clarified liquid; the flocculant is 5%-20% by mass of polyaluminium chloride (PAC) and 5%-20% by mass of calcium hydroxide (slaked lime), the coagulant aid is 0.2%-1.0% by mass of polyacrylamide (PAM), and the pH is adjusted to 7-11.

[0054] The wastewater containing perchlorate enters from the water inlet pipe 14, and enters the mixing area 26, the folding plate area 15, the sedimentation area 45 and the temporary storage area 28 in sequence, wherein the liquid levels of the mixing area 26, the folding plate area 15 and the sedimentation area 45 are kept balanced, and the liquid level in the mixing area 26 is the highest. The wastewater flows into the temporary storage area 28 by relying on water pressure, and the upper clear liquid above the height of the overflow plate 21 will enter the temporary storage area 28 for temporary storage, and will be continuously pumped into the microbial reduction system by a suction pump.

[0055] During this process, when the flocculant is added to the dosing tank 13, the driving motor 36 is started, driving the rotating rod 39 to rotate, stirring the water flow, so that the flocculant is mixed with the wastewater more quickly; because the flow rate of the stirred water flow is affected, part of the upper clear liquid temporarily stored at the bottom of the temporary storage area 28 is periodically intermittently refluxed, and controlled by the reflux pump 27, so that it enters the bottom of the mixing area 26 along the reflux pipe 12 and then the spoiler pipe 25, and guides the wastewater in the mixing area 26 to the folding plate area 15;

[0056] Wastewater flows in the folded plate area 15 along the direction defined by the folded plates. Suspended matter forms turbulence after colliding with the folded plates, gradually flocculates, and finally stabilizes its shape and slows down in the flat baffle area 34, and then enters the sedimentation area 45. Referring to the layout of the different folded plate area 32, the same folded plate area 33 and the flat baffle area 34 shown in the accompanying drawings, the number and position of the folded plates and the flat plates are not limited to the examples shown in the accompanying drawings, and each area can be increased or decreased according to actual needs, and its posture does not necessarily have to be vertical, and can also be horizontal according to actual needs.

[0057] When the wastewater with flocculent suspension enters the left side of the sedimentation zone 45, the large suspended particles lose the upward push of the water flow and sink rapidly. Figure 3 The large suspended particles move downward and rightward, and finally accumulate on the left side of the control plate 29. The small suspended particles flow from the upper side of the fixed plate 17 into the upper sides of the fixed plate 17 and the control plate 29. In the process of moving to the right, the small suspended particles gradually sink and are intercepted by the overflow plate 21.

[0058] The sludge suction pump continuously works at a low power, and the suspended sediment sludge at the bottom of the right area of ​​the sedimentation area 45 is sucked through the sludge pipe 16, the lifting pipe 31 and the suction pipe 43; after a certain period of time, the sludge accumulation on the left side of the control board 29 is detected. If the sludge accumulation is large enough, the motor 23 is controlled to rotate, driving the connecting shaft 44 and the control board 29 to rotate, and the water flow in the sedimentation area 45 flows to the right as a whole. Under the influence of the water flow, the sludge on the left side of the control board 29 gradually alluvial to the right to the suction pipe 43, and at the same time, the power of the sludge suction pump is increased, so that the sludge formed by the deposition of suspended matter can be quickly cleaned The sludge is prevented from accumulating for a long time at the connection between the overflow plate 21 and the bottom of the flocculation tank 11, which is difficult to clean, and at the same time, excessive accumulation of suspended matter is prevented from entering the temporary storage area 28; then the control motor 23 controls the control board 29 to reset, and at the same time the power of the sludge suction pump is restored; during this process, the fixed plate 17 and the control board 29 form an inclined surface, and the water flow on the right side thereof will flow downward under the guidance of the guide groove 42, thereby guiding the flocculent suspended matter to sink to the bottom quickly, and the water flow flows from the left side of the fixed plate 17 and the control board 29 to the right, so the flocculent suspended matter will not be deposited on the surface of the right side of the fixed plate 17 and the control board 29.

[0059] Afterwards, in the microbial reduction system, the reduction system is a UASB reactor, the sludge bed is filled with the bottom mud of the flocculation tank 11 of the fireworks and firecrackers enterprise, and the upper clarified liquid of the flocculation tank 11 enters the UASB reactor, and the ClO4 in the wastewater is reduced by the perchlorate-reducing bacteria under anaerobic conditions. – Converted to Cl - Or other low-valent chloride ions; the reducing bacteria are domesticated from the sludge of urban sewage treatment plants and the sedimentation pond sludge of fireworks and firecrackers enterprises. The sludge obtained from the sludge pipe 16 is not directly sent to the UASB reactor. The reducing bacteria can convert ClO4 – Converted to Cl - .

[0060] In the UASB reactor, wastewater passes through the reactor from bottom to top, and goes through three stages: sulfur autotrophy, heterotrophy, and three-phase separation. All three stages are completed in the same reactor, with an anaerobic treatment temperature of 20℃-40℃, a pH of 6-9, and a hydraulic retention time of 12-72 hours.

[0061] Finally, after biological reduction, the wastewater enters the high-efficiency adsorption system. The wastewater first passes through the quartz sand layer, and the suspended matter, colloids and other substances in the water are removed again by the filtration of the sand and gravel; then it passes through the resin layer, and the residual ClO4 in the water is further adsorbed by ion exchange. – , and finally achieve wastewater discharge or reuse in compliance with standards;

[0062] In addition, after the resin and quartz sand in the ion exchange column are saturated with adsorption, the backwash pump is started to extract the regeneration liquid to desorb and regenerate the exchange column, thereby realizing the reuse of materials. The lower layer of the column is filled with a certain height of quartz sand to achieve physical filtration; usually two ion exchange columns are set up, one for backup and the other for use, and the two columns can be operated separately, in series or in parallel.

[0063] The upper layer of the column is filled with a certain amount of acid-base impregnated modified anion exchange resin, ClO4 – It reacts with the exchangeable ions bound to the active groups of the resin to convert ClO4 – Remove from water bodies.

[0064] Acid-base impregnation modified anion exchange resin, the resin modification method is: first, soak the fresh resin in saturated brine for 10-20 hours, then pour out the brine, rinse with clean water to make the effluent non-yellow, and remove fines and mechanical impurities mixed in the resin. Then soak it in 1%-5% HCl solution for 2-5 hours, and rinse with ultrapure water until neutral. Finally, add the above pretreated ion exchange resin to 2%-10% NaOH solution at a volume ratio of 1:2-5, and seal it for ultrasonic impregnation for 30 minutes-60 minutes, rinse with clean water until neutral for use;

[0065] The regeneration liquid includes at least one of pure water, sodium hydroxide solution with a mass concentration of 4%-8%, and sodium chloride solution with a mass concentration of 10%-30%. The amount of regeneration liquid is 2BV-4BV, the backwash flow rate is 1BV / h-6BV / h, and finally water is used to rinse until the pH of the outlet water is about 7, which means the regeneration is completed. High-concentration regeneration liquid needs to be recovered and centrally processed.

[0066] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0067] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A device for treating perchlorate wastewater by biological reduction and synergistic adsorption, characterized in that: It includes a flocculation pretreatment system, an anaerobic microorganism reduction system and a deep adsorption treatment system. The flocculation pretreatment system includes a flocculation tank, which is divided into a mixing area, a folding plate area, a sedimentation area and a temporary storage area. A water inlet pipe is provided on one side of the mixing area, and a water outlet pipe is provided on one side of the temporary storage area, and the water outlet pipe is connected to the anaerobic microorganism reduction system. A fixed plate and a control plate are provided in the sedimentation area. The fixed plate is located at the upper part of the flocculation tank, and the fixed plate is fixedly connected to the inner wall of the flocculation tank. The control plate is located at the lower part of the flocculation tank. A connecting shaft is fixedly provided at both ends of the control plate, and the connecting shaft is rotatably connected to the inner wall of the flocculation tank. A control motor is fixedly provided on the outer wall of the flocculation tank, and the output shaft of the control motor passes through the side wall of the flocculation tank, and the output shaft of the control motor is fixedly connected to the connecting shaft. The fixing plate and the control plate are respectively provided with a plurality of water holes, and the fixing plate and the control plate are respectively fixed with a plurality of guide grooves on one side close to the temporary storage area, and the water holes and the guide grooves are staggeredly distributed; An installation box is provided between the fixed plate and the temporary storage area, a sludge pipe is provided on one side of the installation box, a lifting pipe is provided on one side of the installation box, and the lifting pipe is connected to the sludge pipe; a lining plate is provided at one end of the lifting pipe away from the installation box, and a plurality of suction pipes are provided on both sides of the lining plate, respectively, the lifting pipe and the suction pipe are distributed at the small particle suspension sedimentation position of the entire sedimentation area, and the fixed plate and the control plate form an inclined surface; the fixed plate and the control plate are used to distinguish between large particle suspension sedimentation and small particle suspension sedimentation in the sedimentation area.

2. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 1, characterized in that: The mixing zone and the folding plate zone are separated by a partition plate, and the partition plate is fixedly connected to the inner wall of the flocculation tank. The folding plate zone is communicated with the lower part of the mixing zone. A dosing tank is provided in the mixing zone, and a fixing frame is fixedly provided on the side of the dosing tank, and the fixing frame is fixedly connected to the inner wall of the flocculation tank and the partition plate.

3. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 2, characterized in that: A mounting plate is respectively provided on both sides of the dosing tank, and the mounting plate is fixedly connected to the flocculation tank and the partition plate. A driving motor is fixedly provided on one side of the mounting plate, and the output shaft of the driving motor passes through the mounting plate. A rotating rod is rotatably provided on the side of the mounting plate away from the driving motor, and the rotating rod is fixedly connected to the output shaft of the driving motor. A plurality of stirring plates are provided on the circumference of the rotating rod.

4. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 3, characterized in that: The folded plate area is located between the mixing area and the sedimentation area, and the upper part of the folded plate area is connected to the sedimentation area. A plurality of folded plates and flat plates are arranged in the folded plate area. The folded plates and the flat plates form an irregular folded plate area, a uniform folded plate area and a flat plate partition area. The water flows through the irregular folded plate area, the uniform folded plate area and the flat plate partition area in sequence, and the suspended matter therein produces flocculation.

5. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 2, characterized in that: The temporary storage area is located on a side of the sedimentation area away from the folding plate area. The temporary storage area and the sedimentation area are separated by an overflow plate. The overflow plate is fixedly connected to the inner wall of the flocculation tank. The temporary storage area is connected to the upper part of the sedimentation area, and a plurality of overflow ports are provided on the top of the overflow plate.

6. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 5, characterized in that: A return pipe is provided on one side of the flocculation tank, one end of which is connected to the temporary storage area, and a plurality of spoiler pipes are fixedly provided on the other end of the return pipe, which are connected to the mixing area. A return pump is provided on the return pipe, and a control valve is detachably installed on the spoiler pipe.

7. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 6, characterized in that: The installation box is detachably installed on a bearing beam, and the bearing beam is fixedly connected to the flocculation tank.

8. The device for treating perchlorate wastewater by biological reduction and synergistic adsorption according to claim 7, characterized in that: The suction pipe is communicated with the lifting pipe, and the lining plate is fixedly connected to the inner wall of the flocculation tank.

9. A process for treating perchlorate wastewater by biological reduction and synergistic adsorption, using the device for treating perchlorate wastewater by biological reduction and synergistic adsorption as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: S1, flocculation and sedimentation, adding a flocculation precipitant to the flocculation tank to remove suspended matter and interfering ions in the water body to obtain wastewater sludge and upper clarified liquid; S2. Microbial reduction. The anaerobic microbial reduction system includes a UASB reactor. The wastewater sludge output from the sludge pipe is used to make a sludge bed of the UASB reactor. The upper clarified liquid of the wastewater is continuously pumped into the UASB reactor. Under anaerobic conditions, ClO4 in the wastewater is reduced by perchlorate-reducing bacteria. – Converted into low-valent chloride ions; S3, deep adsorption treatment, the water enters the ion exchange column, passes through the quartz sand layer and the resin layer in turn, and absorbs the residual ClO4 in the water through ion exchange – ; S4, desorption and regeneration. After the resin and quartz sand in the ion exchange column are saturated with adsorption, the backwash pump is started to extract the regeneration liquid to desorb and regenerate the exchange column, so as to realize the reuse of materials.

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