CN203173900U - Coking waste water deep treatment equipment - Google Patents

Abstract

Coking waste water deep treatment equipment comprises a primary rough filtration device, a secondary rough filtration device, a primary safety protection filtration device, a nanofiltration device, a secondary safety filtration device and an inverse penetration filtration device, wherein the primary rough filtration device is used for carrying out primary rough fitler of coking waste water; the primary rough filtration device is communicated with the primary rough filtration device and used for carrying out secondary rough filtration of the coking waste water; the primary safety protection filtration device is communicated with the secondary rough filtration device and used for carrying out primary safety protection filtration of the coking waster water; the nanofiltration device is communicated with the primary safety protection filtration device and used for carrying out nonofiltration treatment of the coking waste water; the secondary safety protection filtration device is communicated with the nanofiltration device and used for carrying out secondary safety protection filtration of the coking waste water; the inverse penetration filtration device is communicated with the secondary safety protection filtration device and used for carrying out inverse penetration filtration of the coking waste water. The coking waste water deep treatment equipment has better treatment effect.

Description

Coking wastewater advanced treatment equipment

technical field

The utility model relates to advanced treatment equipment for coking wastewater. the

Background technique

Coking wastewater includes the wastewater produced in the process of gas production, coking, metallurgy and ceramic kiln furnace production. It has the characteristics of high organic matter, high phenol, high ammonia nitrogen, and some even contain cyanide. The suspended solids and chroma are also high, which belongs to high Concentration of organic wastewater that is difficult to biodegrade. The COD value of the coking wastewater treated by oxidation and biochemical treatment is still high and cannot be discharged directly. It needs to be treated with coking wastewater advanced treatment equipment. The treatment effect of the existing coking wastewater advanced treatment equipment is poor. the

Utility model content

Based on this, it is necessary to provide a coking wastewater advanced treatment equipment with better treatment effect. the

An advanced treatment equipment for coking wastewater, which is used for advanced treatment of coking wastewater, including:

A first-level coarse filtration device, the first-level coarse filtration device is used to perform a first-level coarse filtration of the coking wastewater;

A secondary coarse filtration device communicated with the primary coarse filtration device, and the secondary coarse filtration device is used for secondary coarse filtration of the coking wastewater;

The first-level security filter device is connected with the second-level coarse filter device, and the first-level security filter device is used for the first-level security filtration of coking wastewater;

The nanofiltration device communicates with the primary security filtration device, and the nanofiltration device is used for nanofiltration treatment of coking wastewater;

A secondary security filter device is communicated with the nanofiltration device, and the secondary security filter device is used for secondary security filtration of coking wastewater; and

The reverse osmosis filter device communicates with the secondary security filter device, and the reverse osmosis filter device is used for reverse osmosis filtration of coking wastewater. the

In one of the embodiments, the primary coarse filtration device is a tank-type filtration device. the

In one of the embodiments, the secondary coarse filtering device is a tank-type filtering device. the

In one of the embodiments, a primary transition device is further included, and the primary transition device communicates with the primary coarse filtration device and the secondary coarse filtration device. the

In one of the embodiments, it further includes a secondary transition device, and the secondary transition device communicates with the nanofiltration device and the secondary security filter device. the

In one of the embodiments, the primary security filter device is provided with an injection port for injecting scale inhibitor. the

In one of the embodiments, the secondary security filter device is provided with an injection port for injecting scale inhibitor. the

The COD value of the coking wastewater treated by the above-mentioned coking wastewater advanced treatment equipment is low, and at the same time, impurities in the coking wastewater can be removed, so that the coking wastewater can be discharged up to the standard. the

Description of drawings

Fig. 1 is the structural representation of the coking wastewater treatment system of an embodiment;

Fig. 2 is a schematic diagram of a reverse osmosis filtration treatment process. the

Detailed ways

In order to facilitate the understanding of the utility model, the utility model will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present utility model are provided in the accompanying drawings. However, the invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive. the

It should be noted that when an element is referred to as being “fixed on” another element, it may be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for purposes of illustration only. the

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of this invention. The terminology used in the description of the utility model herein is only for the purpose of describing specific embodiment, is not intended to limit the utility model. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. the

Please refer to FIG. 1 , a coking wastewater treatment system 10 according to an embodiment includes coking wastewater coal tar treatment equipment 100 , stripping tower 300 , coking wastewater oxidation and biochemical treatment equipment 500 and coking wastewater advanced treatment equipment 700 . the

Please refer to FIG. 2 , coking wastewater coal tar treatment equipment 100 is used to remove coal tar in coking wastewater. Coking wastewater coal tar treatment equipment 100 includes an oil separation device 110 , a regulating device 120 , an air flotation device 130 and an acid analysis device 140 . the

The oil separation device 110 is used to remove suspended oil with larger particles in the coking wastewater. Coking wastewater contains a large amount of tar, if it is not removed, it will have a serious impact on the subsequent physical and chemical treatment (especially when the oil enters the biochemical system, it will greatly reduce the activity of biochemical bacteria). The oil separation device 110 is a treatment structure that uses the difference in specific gravity between oil and water to separate and remove suspended oil with large particles in coking wastewater. Specifically, the oil separation device 110 may be in the form of an oil separation box, a grease separation tank, or an oil separation tank, as long as it can achieve the effect of removing larger particles of suspended oil in the coking wastewater. the

The structure of the oil separator 110 mostly adopts the advection type. The oily coking waste water enters the rectangular pool through the water distribution tank and flows slowly along the horizontal direction. The oil machine is pushed into the oil collecting pipe and then flows into the dehydration tank. The heavy oil and other impurities settled in the pool accumulate in the sludge hopper at the bottom of the pool, and enter the sludge tank through the sludge discharge pipe. The waste water treated with oil separation overflows into the drainage channel and is discharged out of the pool for subsequent treatment. Remove emulsified oil and other contaminants. the

It should be noted that before entering the oil separation device 110 for treatment, the coking wastewater can be treated with a regulating tank or a regulating tank (not shown in the figure) to homogenize the waste water entering the oil separation device 110, thereby ensuring the coking waste water entering the oil separation device 110. The water quality of the waste water is stable, therefore, a regulating pond or regulating tank can be provided before the oil trap 110 . In this embodiment, the volume ratio of the regulating tank or regulating tank to the oil separator 110 is 1:5-1:3. the

The regulating device 120 communicates with the oil separator 110 . The adjustment device 120 is used to accommodate the coking wastewater treated by the oil separation device 110, so that the coking wastewater stored in the adjustment device 120 is homogenized, thereby ensuring that the water quality of the coking wastewater entering the air flotation device 130 is stable, so that it can be adjusted according to The relevant parameters of the coking waste water in the device 120 set the relevant parameters of the air flotation device 130. The regulating device 120 may be a regulating tank or a regulating box. the

The air flotation device 130 communicates with the regulating device 120 . The air flotation device 130 is used to remove larger suspended solids in the coking wastewater. Air flotation is to use highly dispersed micro-bubbles as a carrier to adhere to the hydrophobic-based objects in the wastewater, so that the small bubbles and objects are regarded as a whole, and their overall density is lower than that of water to float to the water surface, thereby realizing solid-liquid or liquid-liquid separation. the process of. The air flotation device 130 may be an advection air flotation device or an upflow air flotation device, preferably an advection air flotation device. the

According to the principle of microbubble generation, the air flotation device 130 can be an aeration air flotation device, a dissolved air flotation device and an electrolytic air flotation device, as long as it can remove larger suspended solids in the coking wastewater. At least two of the aeration air flotation device, the dissolved air flotation device and the electrolysis air flotation device are used in series. the

Dissolved air flotation means that air is pressurized and dissolved in water to reach saturation, and microbubbles are released when the dissolved air flow enters the air flotation tank under reduced pressure. The pressurized dissolved air water can be all or part of the treated water, or it can be the reflux water from the effluent of the air flotation tank. The percentage of the reflux water to the treated water is called the reflux ratio, which is an important factor affecting the air flotation efficiency and must be determined by experiment. . The equipment for the pressurized dissolved air method includes a pressurized pump, an air dissolved tank, and an air compressor. The dissolved air tank is a pressure-bearing steel cylinder, and deflectors or fillers are often arranged inside. The effluent from the dissolved air tank enters the air flotation tank through a pressure reducing valve or a release device. the

The acid analysis device 140 communicates with the air flotation device 130 . The acid analysis device 140 is used to further remove the emulsified coal tar in the coking wastewater. Acid precipitation is to change some substances from a dissolved or colloidal state to a suspended state under acidic conditions, and then separate them (using sedimentation or air flotation). In this embodiment, acid analysis is to use acid (hydrochloric acid or sulfuric acid) to turn emulsified oil in water into suspended matter. It should be noted that the acid analysis can be an independent acid analysis device, or it can be added to the precipitation tower, air flotation and other equipment. In fact, it is an acid dosing device plus a mixer. the

After the coking wastewater is treated by the coking wastewater coal tar treatment equipment 100, the coal tar content is within 20 mg/L, which can avoid excessive coal tar damage to subsequent treatment equipment. the

The stripping tower 300 communicates with the regulating device 130 . The stripping tower 300 is used to remove nitrogen in the form of ammonium ions (NH ⁴⁺ ) and free ammonia (NH ₃ ) in the coking wastewater.

The equilibrium relationship between NH ⁴⁺ and NH ₃ is as follows:

NH ₃ +H ₂ O→NH ⁴⁺ +OH ^-

The equilibrium relationship is affected by the pH value. When the pH value is high, the equilibrium shifts to the left and the proportion of free ammonia increases. At room temperature, when the pH value is about 7, most of the ammonia nitrogen exists in the state of ammonium ions, and when the pH value is about 11, free ammonia accounts for about 98%, and free ammonia is easy to escape from the water. If it is aerated, it can promote Ammonia escapes from the water, where pH is key to the effect. the

The dissociation rate of ammonia nitrogen at different pH and temperature (%, that is, the separation rate of free ammonia and water) is shown in the table below 

pH 20°C 30℃ 35°C 9.0 25 50 58 9.5 60 80 83 10.0 80 90 93 11.0 98 98 98

Generally, the structure of the stripping tower 300 adopts a gas-liquid contact device, and packing is filled inside the tower to increase the contact area. The water after adjusting the pH value is sprinkled on the packing from the upper part of the tower to form water droplets, which fall down sequentially along the gaps of the packing, and contact with the air blown upward by the fan from the bottom of the tower to complete the mass transfer process and make the ammonia flow from the liquid phase to the liquid phase. It turns into the gas phase and discharges with the air to complete the blow-off process, and the removal rate reaches more than 75%. Low-concentration wastewater is usually blown off with air at room temperature, while high-concentration wastewater is often blown off under heating. the

The stripped ammonia gas then enters the ammonia gas absorption and purification tower, where the ammonia gas and the absorption liquid react chemically, so that the gas can be discharged up to the standard without pollution. the

It should be noted that the regulating device 120 can be omitted. At this time, the oil separation device 110 is directly connected with the air flotation device 130. At this time, the coking wastewater treated by the oil separation device 110 directly enters the air flotation device 130 for treatment; or the oil separation device 110 communicates with the stripping tower 300, and the stripping tower 300 communicates with the air flotation device 130. At this time, the coking wastewater treated by the oil separator 110 enters the stripping tower 300 for treatment, and the coking wastewater treated by the stripping tower 300 enters the air Floater 130 performs the treatment. the

Coking wastewater oxidation and biochemical treatment equipment 500 includes a primary electrocatalytic oxidation device 510, a precipitation device 520, a transition device 530, an anaerobic device 540, anoxic device 550, an aerobic device 560, a secondary electrocatalytic oxidation device 570, and a sedimentation tank 580 , biological aerated filter 610 and membrane bioreactor 620 . the

The primary electrocatalytic oxidation device 510 communicates with the acid analysis device 140 . The first-stage electrocatalytic oxidation device 510 is used for electrocatalytic oxidation of coking wastewater to increase the ratio of 5-day biochemical oxygen demand (BOD5) to chemical oxygen demand (COD) in coking wastewater, thereby improving the biodegradability of coking wastewater . Specifically, in this embodiment, the primary electrocatalytic oxidation device 510 is an electrocatalytic oxidation tower. the

The working mechanism of the first-stage electrocatalytic oxidation device 510 is as follows:

Under acidic conditions, in the 6~24V low-voltage DC electrostatic field of electrocatalytic oxidation, in the presence of a catalyst that can efficiently excite hydroxyl radical ions, after adjusting the pH to ≤4, add appropriate amount of FeSO ₄ and H ₂ O ₂ , at the same time generate hydroxyl radicals·OH, because·OH has a strong oxidizing property, so that part of the organic matter becomes CO ₂ and H ₂ O, and the remaining organic matter undergoes hydrolysis-acidification, and the macromolecules are broken into small molecules, which further make the small molecules Organic matter is oxidized into organic acids, thereby increasing the BOD5/COD ratio and laying the foundation for subsequent biochemical treatment.

Mechanism of electrocatalytic oxidation:

①Generation of hydroxyl radicals

Fe ²⁺ +H ₂ O ₂ →Fe ³⁺ +·OH+OH

Fe ²⁺ +·OH→Fe ³⁺ +OHFe ³⁺ +H ₂ O ₂ →Fe ²⁺ +HO ₂ ·+H ⁺

HO ₂ ·+H ₂ O ₂ →O ₂ ↑+H ₂ O+·OH

② Mineralization of organic matter

RH+·OH→R·+H ₂ O

R·+Fe ³⁺ →R ⁺ +Fe ²⁺

R+O ₂ →ROO+→………→CO ₂ ↑+H ₂ O

Note: R is the molecule of organic matter. the

The subsequent treatment process uses the "hydrolysis" and "acidification" of anaerobic bacteria, and the subsequent digestion of aerobic bacteria. The anaerobic organic matter is absorbed and decomposed into CO ₂ and H ₂ O by aerobic bacteria.

The primary precipitation device 520 communicates with the primary electrocatalytic oxidation device 510 . The primary sedimentation device 520 is used to remove the sediment in the coking wastewater. Add caustic soda to the primary precipitation device 520, caustic soda can adjust the pH value of the coking wastewater, the coking wastewater entering the primary electrocatalytic oxidation device 510 generally has a pH value of 3.5~4, and is electrocatalytically oxidized by the primary electrocatalytic oxidation device 510 After the coking wastewater pH value rises to about 4.5, the pH value of the coking wastewater will be adjusted according to the needs of subsequent treatment steps. According to different requirements, the primary sedimentation device 520 can be in various forms such as sedimentation towers, sedimentation tanks, and sedimentation tanks. the

Transition device 530 communicates with settling device 520 . The transition device 530 is used to accommodate the coking wastewater treated by the primary sedimentation device 520 and adjust the pH value of the coking wastewater stored in the transition device 530 . In this embodiment, the pH value of the coking wastewater stored in the transition device 530 is adjusted to 6.5-7.5. It should be noted that the transition device 530 can be a transition tank or a transition tank, the pH value contained in the transition device 530 is not limited to be adjusted to 6.5~7.5, and the pH value of the coking wastewater contained in the transition device 530 is adjusted according to the requirements of subsequent treatment . It should be noted that one of the primary sedimentation device 520 and the transition device 530 can also be selected to adjust the pH value of the coking wastewater. the

Anaerobic device 540 is in communication with transition device 530 . The anaerobic device 540 is used for anaerobic biological treatment of coking wastewater. Anaerobic biological treatment of coking wastewater is used to decompose and convert organic matter in coking wastewater into inorganic matter. The anaerobic device 540 is an anaerobic pond or anaerobic box. the

Anaerobic biological treatment of wastewater refers to the process of decomposing and converting various complex organic substances in wastewater into methane and carbon dioxide through the action of anaerobic microorganisms (including facultative microorganisms) under the condition of no molecular oxygen, also known as anaerobic digestion. . The fundamental difference between the anaerobic biological treatment of wastewater and the aerobic process is that molecular oxygen is not used as the hydrogen acceptor, but combined oxygen, carbon, sulfur, nitrogen, etc. are used as the hydrogen acceptor. the

Anaerobic biological treatment is a complex microbial chemical process, which is completed by the joint action of three major groups of bacteria, namely hydrolytic acidogenic bacteria, hydrogen-producing acetogenic bacteria and methanogenic bacteria. Therefore, the anaerobic digestion process is roughly divided into three consecutive stages, namely, the hydrolytic acidification stage, the hydrogen-producing acetogenic stage and the methanogenic stage. the

The first stage is the hydrolytic acidification stage. Complex macromolecules and insoluble organic substances are first hydrolyzed into small molecules and soluble organic substances under the action of extracellular enzymes, and then penetrate into the cell body, decomposed into small molecules and soluble organic substances, and then penetrate into the cell body, decomposed to produce volatile organic acids, Alcohols, aldehydes, etc. This stage mainly produces higher fatty acids. the

The second stage is the stage of hydrogen production and acetic acid production. Under the action of hydrogen-producing acetogenic bacteria, various organic acids produced in the first stage are decomposed and converted into acetic acid and hydrogen, and carbon dioxide is also formed when most organic acids are degraded. the

The third stage is the methanogenic stage. Methanogenic bacteria convert acetic acid, acetate, carbon dioxide, and hydrogen, among others, into methane. the

The anoxic device 550 communicates with the anaerobic device 540 . Anoxic device 550 is used for biological denitrification treatment of coking wastewater. The anoxic device 550 is an anoxic pool or an anoxic box. the

Biological denitrification treatment means that in an anoxic environment, facultative anaerobic bacteria use NO ₃ ^- or NO ₂ ^- in water instead of oxygen as the electron acceptor, and reduce NO ₃ ^- or NO ₂ ^- to gaseous state through dissimilation Nitrogen oxides NO and N ₂ O, and then continue the process of reduction to N ₂ . Denitrifying bacteria include heterotrophic denitrifying bacteria, autotrophic denitrifying bacteria and facultative chemoautotrophic denitrifying bacteria. Heterotrophic denitrifying bacteria use the oxygen in NO ₃ ^- or NO ₂ ^- to oxidize organic matter and obtain energy under anaerobic conditions; autotrophic denitrifying bacteria such as denitrificans (T.denitrificans) Utilize the oxygen in NO ₃ ^- to oxidize sulfur or thiosulfate to sulfate, and obtain energy from it to assimilate CO ₂ ; facultative chemoautotrophs, such as Paracoccus denitrificans can use the oxidation of hydrogen As an energy source, NO ₃ ^- is reduced to N ₂ O or N ₂ with O ₂ or NO ₃ ^- as an electron acceptor.

The aerobic device 560 is in communication with the anoxic device 550 . The aerobic device 560 is used for aerobic respiration of the activated sludge to further decompose organic matter into inorganic matter (such as water and carbon dioxide). In this embodiment, the aerobic device 560 is a multi-tube internal circulation three-phase biological fluidized bed. It should be noted that the aerobic device 560 may also be other types of three-phase fluidized beds. the

The multi-tube internal circulation three-phase biological fluidized bed is a new type of fluidized bed reactor, which maintains the advantages of the traditional three-phase biological fluidized bed: good mixing performance in the reactor, fast mass transfer rate, and large sludge concentration , While the load of organic matter is high, it solves the problems existing in the traditional three-phase biological fluidized bed, and has a series of new features, as follows: 

①It can control the excessive growth of biofilm thickness. In the traditional three-phase biological fluidized bed, neither the gas velocity nor the liquid velocity can be very large. If it greatly exceeds the terminal sedimentation velocity of the carrier, a large number of biological particles will enter the sedimentation and separation area because the carrier only moves upward in one direction. Therefore, Very easy to take out of the reactor. In order to prevent the loss of the carrier, the shear force of the fluid in the reactor cannot effectively control the excessive growth of the biofilm. In a circulating fluidized bed, since the gas, liquid, and solid circulate between the upflow zone and the downflow zone, the circulation speed is very high, but the carrier is not easily taken out of the reactor. Due to the terminal sinking speed of the carrier, the shearing effect caused by the fluid can effectively control the thickness of the biofilm, so as to avoid the increase of the internal mass transfer resistance caused by the too thick biofilm, so that the biofilm in the circulating fluidized bed can maintain a high activity. the

②The amount of carrier loss is small. Due to the turbulent shear and friction of the circulating fluidized bed, the over-thick biofilm can fall off by itself, so it can prevent the loss of a large amount of carriers. the

③The fluidization performance of the carrier is good. In order to ensure the full fluidization of the carrier, the traditional three-phase biological fluidized bed must adopt a larger aspect ratio without reflux, that is, the diameter of the reactor must be small and the height must be large, while the circulating biological fluidized bed As long as the diameter of the upflow tube is appropriate (too small will cause bubbles to coalesce) and a certain superficial gas velocity is guaranteed, good carrier splitting can be achieved. At the same time, the carrier circulates between the upflow zone and the downflow zone, and the friction and shear force it receives are basically the same. There is no carrier stratification phenomenon in the traditional three-phase fluidized bed, and the carrier fluidization has good uniformity. , which is very beneficial for the good growth of biofilm. the

④ high transfer efficiency of oxygen. The traditional three-phase fluidized bed overflows from the top of the reactor, while in the circulating fluidized bed, the liquid circulates between the riser and the downcomer, and the circulating liquid entrains some small air bubbles in the riser into the reactor. In the downflow tube, only part of the gas escapes from the top, so that the gas-liquid contact time is prolonged, so the oxygenation efficiency is high. the

The internal circulation three-phase biological fluidized bed also has the following advantages: relatively high tolerance to contact oxidation COD, and will not inhibit biochemistry due to high COD in the influent; small flow resistance, the gas supply can be reduced while maintaining the same circulation speed Small size, which reduces operating costs; the initial fluidization of the reactor is easier, reducing the complexity of operation; due to the more compact structure, it can reduce the occupied space and ground. the

The secondary electrocatalytic oxidation device 570 is in communication with the aerobic device 560 . The second-stage electrocatalytic oxidation device 570 is used for deep electrooxidation of coking wastewater to further decompose macromolecular organic matter that has not been completely decomposed in the process. Specifically, in this embodiment, the secondary electrocatalytic oxidation device 570 is an electrocatalytic oxidation tower. the

The oxidants used in the secondary electrocatalytic oxidation device 570 are H ₂ SO ₄ and H ₂ O ₂ .

The secondary precipitation device 580 communicates with the secondary electrocatalytic oxidation device 570 . The secondary sedimentation device 520 is used to remove the sediment in the coking wastewater. According to different requirements, the secondary sedimentation device 580 can be in various forms such as sedimentation towers, sedimentation tanks, and sedimentation tanks. the

The biological aerated filter 610 communicates with the secondary sedimentation device 580 . The biological aerated filter 610 is a kind of aerobic device, which is used to allow activated sludge to perform aerobic respiration and further decompose organic matter into inorganic matter. the

Preferably, the residence time of the coking wastewater in the biological aerated filter 610 is 12 hours. the

Biological aerated filter (BAF) is a new type of biofilm sewage treatment process, with a maximum scale of hundreds of thousands of tons per day, and has been developed to remove nitrogen and phosphorus, and has the ability to remove SS, COD, BOD, nitrification, Phosphorus removal and removal of AOX (harmful substances). The biological aerated filter 610 integrates biological oxidation and interception of suspended solids, saving the follow-up sedimentation tank (secondary sedimentation tank), with volume load, hydraulic load, short hydraulic retention time, less infrastructure investment required, and good effluent quality: Low operating energy consumption and low operating costs. the

The membrane bioreactor 620 communicates with the biological aerated filter 610 . Membrane bioreactor 620 is a kind of aerobic device, which is used to allow activated sludge to perform aerobic respiration and further decompose organic matter into inorganic matter. Membrane bioreactor 620 cooperates with aerobic device 560, and the water quality of the treated water is good. the

Membrane bioreactor 620 (MBR), as a reuse water treatment process. Due to the interception effect of MBR, the loss of microorganisms is avoided, and a high sludge concentration can be maintained in the bioreactor, thereby increasing the volume load, reducing the sludge load, and having strong impact resistance. Due to the interception effect of the membrane, the SRT is prolonged, creating an environment conducive to the growth of slow-growing microorganisms, such as the growth of nitrifying bacteria, which can improve the nitrification capacity of the system, and at the same time help to improve the treatment efficiency of refractory macromolecular organic matter and promote its degradability. Complete breakdown. In the process of operation, the large hydraulic circulation is conducive to the uniform mixing of sewage, so that the activated sludge has good dispersion and greatly improves the treatment efficiency and stability. the

Coking wastewater oxidation and biochemical treatment equipment 500 comprehensively utilizes electrocatalytic oxidation and biological oxidation technology, which can effectively degrade organic matter in coking wastewater. the

Further, the coking wastewater treatment system 10 also includes a sludge treatment device 900 . The sludge treatment equipment 900 includes a sludge tank 910 and a filter press 920 . The sediment produced by air flotation device 130 , primary sedimentation device 520 , anoxic device 550 , aerobic device 560 , secondary sedimentation device 580 , biological aerated filter 610 and membrane bioreactor 620 is sent to sludge tank 910 . The sludge in the sludge tank 910 is fed into the filter press through a pneumatic diaphragm pump and filtered, the sludge is transported outside, and the filtrate is injected back into the regulating device 120 . the

Coking wastewater advanced treatment equipment 700 includes a primary coarse filter device 710, a secondary coarse filter device 720, a primary transition device 730, a primary security filter device 740, a nanofiltration device 750, a secondary transition device 760, and a secondary security filter device. 770 and reverse osmosis filter device 780. the

The primary coarse filtration device 710 communicates with the membrane bioreactor 620 . The primary coarse filter device 710 is used to filter the coking wastewater treated by the coking wastewater oxidation and biochemical treatment equipment 500, and filter fine suspended solids, microorganisms, and some heavy metal ions in the water, and can effectively reduce the chroma of the water. the

Preferably, the primary coarse filter device 710 is a tank-type filter device, the shell is generally made of carbon steel, stainless steel or glass fiber reinforced plastic, and the inside is filled with filter material. the

Preferably, the filter material of the primary coarse filtration device 710 is selected from at least one of zeolite and glauconite. Zeolites are preferred. Zeolite is a kind of polar substance, which is a highly polar adsorbent. It has a strong adsorption effect on polar molecules and unsaturated organic molecules, such as halogenated hydrocarbons. It has a strong adsorption effect on non-polar molecules with high polarizability Molecules also have a higher selective adsorption advantage. Zeolite filter material mainly includes natural clinoptilolite filter material and activated zeolite filter material. the

The secondary coarse filtration device 720 communicates with the primary coarse filtration device 710 . The secondary rough filtration device 720 is used to remove fine suspended solids, microorganisms, and some heavy metal ions in the coking wastewater, and can effectively reduce the chroma of the water. the

The secondary coarse filter device 720 is a tank-type filter device, the shell is generally made of carbon steel, stainless steel or fiberglass, and the inside is filled with filter material. the

Preferably, the filter material of the secondary rough filtration device 720 is selected from at least one of activated carbon and bamboo charcoal, preferably activated carbon. Activated carbon filter material has developed mesopore structure and developed specific surface area, large adsorption capacity, fast filtration speed, and no zinc salt. It is an excellent filter material. the

The primary transition device 730 communicates with the secondary coarse filtration device 720 . The primary transition device 730 is used to accommodate the coking wastewater treated by the secondary coarse filter device 720 to keep the water flow in and out of the whole system stable and play a buffer role. The primary transition device 730 may be a transition tank or a transition tank. It should be noted that the primary transition device 730 can also be arranged between the primary coarse filtration device 710 and the secondary coarse filtration device 720, that is, the primary transition device 730 communicates with the primary coarse filtration device 710 and the secondary coarse filtration device. 720 , the coking wastewater filtered by the primary coarse filtration device 710 enters the primary transition device 730 , and then enters the secondary coarse filtration device 720 for secondary coarse filtration. the

The primary security filtering device 740 communicates with the primary transition device 730 . In the process of cartridge filtration, water enters the inside of the filter element from the outside of the microfiltration filter element, and micro suspended solids or fine impurity particles are trapped outside the filter element. The primary security filter device 740 is used to filter and remove impurities larger than 50 μm. The filter material of the first-level security filter device 740 is polypropylene, with a gap of 1 μm to 300 μm, and adopts a five-inner shaft dense inner and outer sparse structure. The primary security filter device 740 is provided with a drug injection port for injecting scale inhibitor. the

The nanofiltration device 750 communicates with the primary security filtration device 740 . Nanofiltration (NF) is a membrane separation technology between ultrafiltration and reverse osmosis, its molecular weight cut-off is in the range of 80-1000, and the pore size is several nanometers. After being filtered by advanced filtration devices such as nanofiltration, about 70% of the water becomes water that meets the water quality standards. These waters are exported, and the remaining 30% of the water will continue to accumulate as the amount of filtered water continues to increase. , for concentrated water. The concentrated water obtained after filtering by the nanofiltration device 750 is injected back into the regulating device 120 . the

Secondary transition device 760 communicates with nanofiltration device 750 . The secondary transition device 760 is used to accommodate the coking wastewater treated by the nanofiltration device 750. The secondary transition device 760 may be a transition tank or a transition tank. the

The secondary security filtering device 770 communicates with the secondary transition device 760 . The filter material of the secondary security filter device 770 is polypropylene, with a gap of 1 μm to 300 μm, and adopts a five-inner shaft dense inner and outer sparse structure. The secondary security filter device 770 is provided with an injection port for injecting scale inhibitors. the

The reverse osmosis filter device 780 communicates with the secondary security filter device 770 . the

Reverse osmosis (RO) technology is an advanced membrane separation technology. This technology allows certain components in the solution to be separated to pass through a semi-permeable membrane with selective permeability—reverse osmosis membrane under the action of pressure. On the high pressure side is a concentrated solution of other trapped components. It is a high-tech with energy saving, high efficiency, no pollution and strong practicability. the

The natural flow of water through a semipermeable membrane into a solution or from a dilute solution to a more concentrated solution is called osmosis. This kind of membrane with selective permeability to water or solution is called semipermeable membrane. However, adding appropriate pressure on the side of the concentrated solution can stop the permeation. When the permeation of the dilute solution to the concentrated solution stops, the pressure is called osmotic pressure. Reverse osmosis is to apply a higher pressure than the natural osmotic pressure on one side of the concentrated solution, reverse the natural osmotic direction, and press the water in the concentrated solution to the other side of the semi-permeable membrane, which is opposite to the normal osmotic process in nature, so it is called for reverse osmosis. This special semi-permeable membrane is called reverse osmosis membrane. the

The main part of the main body of the reverse osmosis filtration device 780 is the RO membrane module. RO membrane, that is, reverse osmosis membrane, has a pore size of 0.0001 microns and can filter 70% of macromolecules, including salt. The RO membrane used in this system can ensure that the desalination of the host machine meets the design requirements in a long-term, stable and reliable manner. The reverse osmosis host design reverse osmosis water temperature is 25°C, the water utilization rate is 70%, and the total desalination rate of the system is greater than or equal to 97%. And there is a random display of conductivity, and it has an automatic alarm function. the

Please refer to Figure 2, which is a flowchart of the RO treatment process. the

The clean water filtered by the reverse osmosis filter device 780 flows into the clean water pool 800 and can be reused for greening or other process water; the filtered concentrated water is reinjected into the regulating device 120 . the

Concentrated water and backwash water after the primary coarse filtration device 710 , secondary coarse filtration device 720 , nanofiltration device 750 and reverse osmosis filtration device 780 are reinjected into the regulating device 120 . the

The COD value of the coking wastewater treated by the coking wastewater advanced treatment equipment 700 is low, and the impurities in the coking wastewater can be removed at the same time, so that the coking wastewater can be discharged up to the standard. the

After coking wastewater is treated by coking wastewater coal tar treatment equipment 100, coking wastewater oxidation and biochemical treatment equipment 500 and coking wastewater advanced treatment equipment 700, suspended solids, organic matter and ammonia nitrogen in coking wastewater can be effectively removed, and the final output of treated Coking wastewater can meet discharge standards. The final output wastewater has a pH value of 7~9, COD less than 500mg/L, suspended matter less than 20mg/L, volatile phenol less than 0.5mg/L, cyanide less than 0.5mg/L, and ammonia nitrogen less than 25mg/L. the

It should be noted that the primary transition device 730 and the secondary transition device 760 can be omitted. At this time, the primary security filter device 740 is directly connected with the secondary coarse filter device 720, and the secondary security filter device 770 is directly connected with the nanofiltration device 750. . the

Please refer to Fig. 1, the coking wastewater treatment method of an embodiment, comprises the following steps:

Step S101 , providing a coking wastewater treatment system 10 . the

Step S102 , using the oil separator 110 to remove suspended oil with larger particles in the coking wastewater. the

Specifically, the oily wastewater enters the rectangular pool through the water distribution tank, and flows slowly along the horizontal direction. During the flow, the oil floats to the water surface, and is pushed into the oil collecting pipe by the oil collecting pipe or the oil scraper installed on the surface of the pool, and then flows into the dewatering pipe. Can. The heavy oil and other impurities settled in the pool accumulate in the sludge hopper at the bottom of the pool, and enter the sludge tank through the sludge discharge pipe. The waste water treated with oil separation overflows into the drainage channel and is discharged out of the pool for subsequent treatment. Remove emulsified oil and other contaminants. the

Preferably, the coking wastewater stays in the oil trap 110 for 2 hours to 6 hours. the

It should be noted that before entering the oil separation device 110 for treatment, the coking wastewater can be treated with a regulating tank or a regulating tank (not shown in the figure) to homogenize the waste water entering the oil separation device 110, thereby ensuring the coking waste water entering the oil separation device 110. The water quality of the waste water is stable, therefore, a regulating pond or regulating tank can be provided before the oil trap 110 . In this embodiment, the volume ratio of the regulating pool or regulating tank to the oil separator 110 is 1:5-1:3. the

Preferably, the coking wastewater treated by the oil separation device 110 is treated with a regulating device, so that the coking wastewater treated by the oil separation device 110 is homogenized. the

Step S103, using the air flotation device 130 to remove larger suspended matter in the coking wastewater. the

Air flotation is to use highly dispersed micro-bubbles as a carrier to adhere to the hydrophobic-based objects in the wastewater, so that the small bubbles and objects are regarded as a whole, and their overall density is lower than that of water to float to the water surface, thereby realizing solid-liquid or liquid-liquid separation. the process of. The air flotation device 130 may be an advection air flotation device or an upflow air flotation device, preferably an advection air flotation device. the

According to the principle of microbubble generation, the air flotation device 130 can be an aeration air flotation device, a dissolved air flotation device and an electrolytic air flotation device, as long as it can remove larger suspended solids in the coking wastewater. At least two of the aeration air flotation device, the dissolved air flotation device and the electrolysis air flotation device are used in series. the

Dissolved air flotation means that air is pressurized and dissolved in water to reach saturation, and microbubbles are released when the dissolved air flow enters the air flotation tank under reduced pressure. The pressurized dissolved air water can be all or part of the treated water, or it can be the reflux water from the effluent of the air flotation tank. The percentage of the reflux water to the treated water is called the reflux ratio, which is an important factor affecting the air flotation efficiency and must be determined by experiment. . The equipment for the pressurized dissolved air method includes a pressurized pump, an air dissolved tank, and an air compressor. The dissolved air tank is a pressure-bearing steel cylinder, and deflectors or fillers are often arranged inside. The effluent from the dissolved air tank enters the air flotation tank through a pressure reducing valve or a release device. the

Preferably, a demulsifier is placed in the reaction zone of the air flotation device 130, and the demulsifier is preferably aluminum chloride with a concentration of 7%. Of course, other commonly used demulsifiers in the industry are also acceptable. Specifically, in the process of operation, the dosage of the demulsifier is determined according to the content of coal tar in the coking wastewater entering the air flotation device 130. When the oil content in the coking wastewater is within 400 mg/L, the dosage of the demulsifier is 500 mg/L. L (volume ratio of the amount of demulsifier to coking wastewater), when the oil content is 400mg/L~1000mg/L, the dosage of demulsifier is 400mg/L~1000mg/L. the

Preferably, the time for the air flotation device 130 to treat coking wastewater is 0.5 hours to 2 hours. the

Preferably, the oil content of the coking wastewater treated by the air flotation device 130 is within 30 mg/L. the

Preferably, the homogenized coking wastewater regulated by the regulating device 120 uses the stripping tower 300 to remove the ammonium ions (NH ⁴⁺ ) and free ammonia (NH ₃ ) in the coking wastewater before entering the air flotation device 130 nitrogen. The coking wastewater treated by the stripping tower 300 enters the regulating device 120 again to adjust homogenization, and then uses the air flotation device to remove larger suspended matter in the coking wastewater.

Step S104, use the acid analysis device 140 to further remove the emulsified coal tar in the coking wastewater. the

The coking wastewater discharged from the air flotation device 130 enters the acid analysis device 140, and sulfuric acid is added for acid analysis treatment to further remove the emulsified coal tar in the coking wastewater. the

Preferably, the dosage of sulfuric acid is 50mg/L. There are two ways to add sulfuric acid. One is to add 98% concentrated sulfuric acid directly. The sewage system contains aeration and stirring devices, which can be mixed evenly; the other is to dilute 98% concentrated sulfuric acid to a concentration of 10%~20%. sulfuric acid solution. the

After the coking wastewater is treated in steps S101~step S104, the coal tar content is within 20mg/L, which can prevent the excessive coal tar in the coking wastewater from causing damage to the subsequent treatment equipment. the

Step S105 , using the primary electrocatalytic oxidation device 510 to perform electrocatalytic oxidation on the coking wastewater, so as to increase the ratio of 5-day biochemical oxygen demand (BOD5) to chemical oxygen demand (COD) in the coking wastewater. the

Preferably, the coking wastewater stays in the primary electrocatalytic oxidation device 510 for 40 minutes to 90 minutes. the

Specifically, under acidic conditions, in the 6-24V low-voltage DC electrostatic field of electrocatalytic oxidation, in the presence of a catalyst, after adjusting the pH to 4 or less, the catalysts in the electrocatalytic oxidation treatment are FeSO ₄ and H ₂ O ₂ .

In this step, FeSO ₄ and H ₂ O ₂ are added under acidic conditions to generate hydroxyl radicals OH at the same time. Because OH has strong oxidizing properties, part of the organic matter becomes CO2 and H2O, and the remaining organic matter is hydrolyzed-acidified. Large molecules are broken into small molecules, which further oxidizes small molecular organic matter into organic acids, thereby increasing the BOD5/COD ratio and laying the foundation for subsequent biochemical treatment. The subsequent treatment process uses the "hydrolysis" and "acidification" of anaerobic bacteria, and the subsequent digestion of aerobic bacteria. The anaerobic organic matter is absorbed and decomposed into CO ₂ and H ₂ O by aerobic bacteria.

Step S106, using the primary sedimentation device 520 to remove the sediment in the coking wastewater. the

Specifically, a sedimentation tower with a sludge hopper is used, and the sewage with suspended solids enters and is left to stand until the suspended solids are deposited in the sludge hopper to complete the sedimentation process. the

According to different requirements, the primary sedimentation device 520 can be in various forms such as sedimentation towers, sedimentation tanks, and sedimentation tanks. the

Step S107, using the transition device 530 to adjust the pH value of the coking wastewater. the

In this embodiment, sodium hydroxide solution is used to adjust the pH value of the coking wastewater stored in the transition device 530 to 6.5-7.5. Preferably, the mass concentration of the sodium hydroxide solution is 7%. It should be noted that the pH value stored in the transition device 530 is not limited to be adjusted to 6.5-7.5, and the pH value of the coking wastewater stored in the transition device 530 is adjusted according to the requirements of subsequent treatment. At the same time, it is not limited to using sodium hydroxide solution to adjust the pH value of coking wastewater, and other alkaline solutions such as potassium hydroxide, sodium carbonate, etc. or alkaline wastewater can be used. the

Step S108 , using the anaerobic device 540 to perform anaerobic biological treatment on the coking wastewater. the

Anaerobic biological treatment of coking wastewater is used to decompose and convert organic matter in coking wastewater into inorganic matter. Preferably, the coking wastewater stays in the anaerobic device 540 for 6 hours to 12 hours. the

Anaerobic biological treatment of wastewater refers to the process of decomposing and converting various complex organic substances in wastewater into methane and carbon dioxide through the action of anaerobic microorganisms (including facultative microorganisms) under the condition of no molecular oxygen, also known as anaerobic digestion. . The fundamental difference between the anaerobic biological treatment of wastewater and the aerobic process is that molecular oxygen is not used as the hydrogen acceptor, but combined oxygen, carbon, sulfur, nitrogen, etc. are used as the hydrogen acceptor. the

Anaerobic biological treatment is a complex microbial chemical process, which is completed by the joint action of three major groups of bacteria, namely hydrolytic acidogenic bacteria, hydrogen-producing acetogenic bacteria and methanogenic bacteria. Therefore, the anaerobic digestion process is roughly divided into three consecutive stages, namely, the hydrolytic acidification stage, the hydrogen-producing acetogenic stage and the methanogenic stage. the

The first stage is the hydrolytic acidification stage. Complex macromolecules and insoluble organic substances are first hydrolyzed into small molecules and soluble organic substances under the action of extracellular enzymes, and then penetrate into the cell body, decomposed into small molecules and soluble organic substances, and then penetrate into the cell body, decomposed to produce volatile organic acids, Alcohols, aldehydes, etc. This stage mainly produces higher fatty acids. the

The second stage is the stage of hydrogen production and acetic acid production. Under the action of hydrogen-producing acetogenic bacteria, various organic acids produced in the first stage are decomposed and converted into acetic acid and hydrogen, and carbon dioxide is also formed when most organic acids are degraded. the

The third stage is the methanogenic stage. Methanogenic bacteria convert acetic acid, acetate, carbon dioxide, and hydrogen, among others, into methane. the

Step S109 , using the anoxic device 550 to perform biological denitrification treatment on coking wastewater. the

Preferably, the coking wastewater stays in the anoxic device 550 for 6 hours to 12 hours. the

Biological denitrification treatment means that in an anoxic environment, facultative anaerobic bacteria use NO ₃ ^- or NO ₂ ^- in water instead of oxygen as the electron acceptor, and reduce NO ₃ ^- or NO ₂ ^- to gaseous state through dissimilation Nitrogen oxides NO and N ₂ O, and then continue the process of reduction to N ₂ . Denitrifying bacteria include heterotrophic denitrifying bacteria, autotrophic denitrifying bacteria and facultative chemoautotrophic denitrifying bacteria. Heterotrophic denitrifying bacteria use the oxygen in NO ₃ ^- or NO ₂ ^- to oxidize organic matter and obtain energy under anaerobic conditions; autotrophic denitrifying bacteria such as denitrificans (T.denitrificans) Utilize the oxygen in NO ₃ ^- to oxidize sulfur or thiosulfate to sulfate, and obtain energy from it to assimilate CO ₂ ; facultative chemoautotrophs, such as Paracoccus denitrificans can use the oxidation of hydrogen As an energy source, NO ₃ ^- is reduced to N ₂ O or N ₂ with O ₂ or NO ₃ ^- as an electron acceptor.

Step S110, using the aerobic device 560 to perform aerobic treatment on the coking wastewater. the

In this step, activated sludge is added to the aerobic device 560, generally obtained from a domestic sewage plant, and the activated sludge is aerated strongly to make the dissolved oxygen above 2 mg/L. the

Preferably, the coking wastewater stays in the aerobic device 560 for 12 hours to 36 hours. the

Step S111 , using the secondary electrocatalytic oxidation device 570 to perform deep electrocatalytic oxidation treatment on the coking wastewater. the

Preferably, before the deep electrocatalytic oxidation treatment of the coking wastewater, sulfuric acid is used to adjust the pH value of the coking wastewater treated by the aerobic device 560 to 3.5-4.5. Specifically in this embodiment, the mass concentration of sulfuric acid is 5%. the

Preferably, the catalysts used for deep electrocatalytic oxidation treatment of coking wastewater using the secondary electrocatalytic oxidation device 570 are H ₂ SO ₄ and H ₂ O ₂ .

Preferably, the coking wastewater stays in the secondary electrocatalytic oxidation device 570 for 45 minutes. the

Step S112, using the secondary sedimentation device 580 to remove the sediment in the coking wastewater. the

According to different requirements, the secondary sedimentation device 580 can be in various forms such as sedimentation towers, sedimentation tanks, and sedimentation tanks. the

Preferably, sodium hydroxide is added to the coking wastewater in this step. the

Step S113 , using the biological aerated filter 610 to treat the coking wastewater. the

Preferably, the residence time of the coking wastewater in the biological aerated filter 610 is 12 hours. the

Step S114 , using the membrane bioreactor 620 to treat the coking wastewater. the

Preferably, in the coking wastewater treated in steps S101-114, COD is reduced to less than 500 mg/L, volatile phenols are less than 0.5 mg/L, oil content is less than 20 mg/L, and suspended solids are less than 20 mg/L. the

Step S115 , using the primary coarse filtration device 710 to perform primary coarse filtration on the coking wastewater. the

Primary coarse filtration is used to filter fine suspended solids, microorganisms, some heavy metal ions, etc. in water, and can effectively reduce the chroma of water. the

Step S116 , using the secondary coarse filtration device 720 to perform secondary coarse filtration of the coking wastewater. the

Step S117 , using the primary security filter device 740 to perform primary security filtration on the coking wastewater. the

The primary security filter is used to remove impurities above 50μm in coking wastewater. the

Preferably, in the process of carrying out primary security filtration, can add antiscalant in primary security filter device 740. the

Preferably, a step is further included between step S116 and step S117: injecting the coking wastewater that has undergone secondary rough filtration into the first transition device 730 . the

Step S118 , using the nanofiltration device 750 to perform nanofiltration on the coking wastewater. the

Nanofiltration of coking wastewater is used to remove 1nm~10nm impurities in coking wastewater. the

Step S119 , using the secondary security device 770 to perform secondary security filtration on the coking wastewater. the

Preferably, during the process of performing secondary security filtration, a scale inhibitor can be added to the secondary security filtration device 770 . the

Preferably, a step is further included between step S118 and step S119: injecting the coking wastewater that has undergone nanofiltration into the second transition device 760 . the

Step S120, using the reverse osmosis filtration device 780 to perform reverse osmosis filtration treatment on the coking wastewater. the

The coking wastewater treated by reverse osmosis filtration flows into the clean water tank 800 and can be used for greening or other process water; the filtered concentrated water is reinjected into the regulating device 120 . the

Preferably, the concentrated water and backwash water obtained after processing in step S115 , step S116 , step S118 and step S120 are reinjected into the regulating device 120 . the

Preferably, the sediment produced in step S103 , step S106 , step S109 , step S110 , step S112 , step S113 and step S114 is sent to the sludge tank 910 . After the sludge in the sludge pool 910 is filtered by the filter press, the sludge is transported outside, and the filtrate is injected back into the regulating device 120 . the

Coking wastewater After being treated by the above coking wastewater treatment method, the suspended matter, organic matter and ammonia nitrogen in the coking wastewater can be effectively removed, and the final output of the treated coking wastewater can meet the discharge standard. the

The above-mentioned embodiments only express several implementations of the utility model, and the description thereof is relatively specific and detailed, but it should not be construed as limiting the patent scope of the utility model. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the scope of protection of the utility model patent should be based on the appended claims. the

Claims (7)

1. A coking wastewater advanced treatment equipment for advanced treatment of coking wastewater, characterized in that it comprises: A first-level coarse filtration device, the first-level coarse filtration device is used to perform a first-level coarse filtration of the coking wastewater; A secondary coarse filtration device communicated with the primary coarse filtration device, and the secondary coarse filtration device is used for secondary coarse filtration of the coking wastewater; The first-level security filter device is connected with the second-level coarse filter device, and the first-level security filter device is used for the first-level security filtration of coking wastewater; The nanofiltration device communicates with the primary security filtration device, and the nanofiltration device is used for nanofiltration treatment of coking wastewater; A secondary security filter device is communicated with the nanofiltration device, and the secondary security filter device is used for secondary security filtration of coking wastewater; and The reverse osmosis filter device communicates with the secondary security filter device, and the reverse osmosis filter device is used for reverse osmosis filtration of coking wastewater. the 2 . The advanced treatment equipment for coking wastewater according to claim 1 , wherein the first-stage coarse filtration device is a tank-type filter device. 3 . the 3. The advanced treatment equipment for coking wastewater according to claim 1, characterized in that, the secondary coarse filter device is a tank-type filter device. the 4 . The advanced treatment equipment for coking wastewater according to claim 1 , further comprising a primary transition device, the primary transition device being connected to the primary coarse filtration device and the secondary coarse filtration device. the 5 . The advanced treatment equipment for coking wastewater according to claim 4 , further comprising a secondary transition device connected to the nanofiltration device and the secondary security filter device. the 6. The advanced treatment equipment for coking wastewater according to claim 1, characterized in that the primary security filter device is provided with a dosing port for injecting scale inhibitor. the 7. The advanced treatment equipment for coking wastewater according to claim 1, characterized in that the secondary security filter device is provided with a dosing port for injecting scale inhibitor. the

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