CN114380430A - Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling - Google Patents

Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling Download PDF

Info

Publication number
CN114380430A
CN114380430A CN202111621193.9A CN202111621193A CN114380430A CN 114380430 A CN114380430 A CN 114380430A CN 202111621193 A CN202111621193 A CN 202111621193A CN 114380430 A CN114380430 A CN 114380430A
Authority
CN
China
Prior art keywords
rotor
ozone
packed bed
iron
wastewater
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111621193.9A
Other languages
Chinese (zh)
Inventor
焦纬洲
刘有智
景佳鑫
苗富铭
祁贵生
袁志国
张巧玲
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
North University of China
Original Assignee
North University of China
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by North University of China filed Critical North University of China
Priority to CN202111621193.9A priority Critical patent/CN114380430A/en
Publication of CN114380430A publication Critical patent/CN114380430A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C02F1/78—Treatment of water, waste water, or sewage by oxidation with ozone
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/38—Organic compounds containing nitrogen
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2201/00—Apparatus for treatment of water, waste water or sewage
    • C02F2201/002—Construction details of the apparatus

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Treatment Of Water By Oxidation Or Reduction (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)

Abstract

The invention provides a reaction device and a method for treating nitrobenzene wastewater by integrated reinforced iron-carbon micro-electrolysis-ozone coupling, wherein the device comprises an oxygen cylinder, an ozone generator, a rotary packed bed, a pump and a nitrobenzene wastewater reservoir, and a circular rotor is rotatably arranged in the rotary packed bed; the rotor is sequentially provided with a rotor outer shell, an annular partition plate and a rotor inner shell from outside to inside, through holes are formed in the rotor outer shell, the annular partition plate and the rotor inner shell, a metal wire mesh made of metal wire coils is filled between the rotor outer shell and the annular partition plate, and iron carbon balls are stacked between the annular partition plate and the rotor inner shell; the rotary packed bed is provided with an air inlet, an air outlet, a liquid inlet and a liquid outlet; the nitrobenzene wastewater reservoir is connected with a pump, and the pump is connected with a liquid inlet of the rotary packed bed; the oxygen cylinder is connected with an ozone generator, and the ozone generator is connected with an air inlet of the rotary packed bed. The invention simplifies the process procedures, simplifies the process steps,saves the cost of wastewater treatment, and can effectively avoid Fe2+Is wasted.

Description

Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling
Technical Field
The invention belongs to the technical field of nitrobenzene wastewater treatment, and particularly discloses a reaction device and a method for treating nitrobenzene wastewater by integrated reinforced iron-carbon micro-electrolysis-ozone coupling.
Background
The iron-carbon micro-electrolysis technology takes waste scrap iron and activated carbon particles as the filling materials of a reactor, and uses the difference of oxidation reduction potentials of iron and carbon to enable the waste scrap iron and the activated carbon particles to form countless micro primary batteries in the reactor, so as to reduce and degrade organic pollutants in wastewater. The reaction formula is as follows:
anode:
Fe-2e-→Fe2+ E(Fe/Fe2+) =0.44V (formula 1)
Cathode:
2H++2e-→2[H] →H2 E(H+/ H2) =0.00V (acid) (formula 2)
And (3) cathode reaction under aeration conditions:
O2 + 4H+ + 4e– → 2H2O E (O2 / H2o) = +1.23V (acidic) (formula 3)
O2 + 2H+ + 2e–→ 2H2O2 E (O2 / H2O2) = +0.68V (acid) (formula 4)
O2 + 2H2O + 4e–→ 4OH– E(O2 /OH–) = +0.40V (neutral weak alkaline) (formula 5)
In the reaction, iron as anode loses electrons and transfers to the carbon surface, and H on the surface is removed+Capture of the nascent state [ H]。[H]Is a reducing agent with stronger reducibility than direct electron transfer, can effectively reduce nitro groups, azo bonds and the like on organic pollutants, thereby breaking downThe stable structure of the refractory organic molecules makes them easy to degrade. Nitrobenzene is difficult to be oxidized and degraded because the nitro group on the benzene ring has strong electron-withdrawing effect to passivate the benzene ring. The iron-carbon micro-electrolysis method can effectively reduce the nitro group on the nitrobenzene into amino group, activate the benzene ring and make the benzene ring easy to degrade. Therefore, the iron-carbon micro-electrolysis technology is often used for the pretreatment of nitrobenzene wastewater. However, after the iron-carbon micro-electrolysis bed runs for a long time, the surface of iron-carbon is easily covered by the generated iron oxide, and the coagulation effect of ferrous iron generated by electrolysis is easy to form stable flocculate and gradually deposit on the surface of the filler, so that the filler is passivated and inactivated, and the electrolysis reaction is hindered, so that the iron-carbon micro-electrolysis bed is difficult to run continuously for a long time.
The supergravity technology is a breakthrough technology for strengthening multiphase transfer and reaction processes developed in the 80 th of the 20 th century, and the principle of the supergravity technology is that in a supergravity rotating packed bed (also called a supergravity machine), a filler rotates at a high speed to form a supergravity environment, liquid is sheared and atomized by the filler, the contact area between phases is increased, and the mass transfer, the heat transfer and the reaction processes controlled by a liquid phase are greatly strengthened due to the quick update of the surface.
The nitrobenzene wastewater flows in a porous medium or a pore channel under a supergravity environment, and the liquid is cut into an extremely thin liquid film, micro liquid fog and liquid drops by huge shearing force, so that the specific surface area is increased, the phase interface updating rate and the two-phase contact frequency are accelerated, a larger liquid amount is contacted with the iron-carbon filler in unit time, the high concentration of organic matters on the surface of the filler is maintained, and the mass transfer driving force is enhanced; as for the iron-carbon material, the iron-carbon material is filled in the rotor as a filler, the iron-carbon filler is changed from the original static state into the rapid movement state in the high-speed rotating super-gravity field, and under the action of centrifugal force, the liquid instantaneously disappears on the surface of the filler, but the liquid instantaneously reappears, and the surface is rapidly updated in a repeated alternation manner, so that the adhesion of iron oxide on the surface of the filler can be effectively avoided, and the inactivation of the iron-carbon filler is avoided.
Because ozone has the defects of poor water solubility and slow mass transfer rate, the utilization rate of ozone is low when the wastewater is treated. The gas-liquid contact mode in the hypergravity rotating packed bed can be divided into countercurrent, cocurrent and cross flow. The rotors in the conventional rotary packed beds are all of integral structure, i.e. the packing in the rotors is driven by a single rotating shaft, and the first patent in the aspect of the super-gravity rotary bed is provided by the british chemical industry (ICI) in 1979 and has the patent number EP0002568, and the subsequent patents which are successively disclosed at home and abroad also basically continue the rotor structure. In 2001, Sandilya et al found that the mass transfer coefficient of the gas phase mass transfer process in the rotating packed bed is lower than that in the packed tower, because the gas is subjected to friction after entering the packing, the relative slip velocity with the packing is very small, the gas phase interface cannot be rapidly updated, and the mass transfer rate is further reduced due to the phenomenon of uneven distribution of the liquid phase in the packing. In 2004, the research of D P Rao et al shows that the liquid phase mass transfer process is mainly enhanced in the super-gravity rotating bed, the use of high specific surface area filler under the super-gravity field is the main reason, and the gas phase mass transfer coefficient is equivalent to that of the traditional packed tower. In 2005, chandra a proposed a layered Packed Rotating bed (SP-RPB) for the first time, aiming at the problem that the gas phase slip velocity in the countercurrent Rotating Packed bed of the monolithic Packing is too small (2-3 m/s) and thus the centrifugal acceleration has almost no influence on the gas phase mass transfer coefficient, and divided the monolithic rotor Packing in the ordinary Rotating Packed bed into a plurality of rings of mutually nested Packing rings, which improved the tangential slip velocity of the gas phase in the Rotating Packing. A series of rectification and absorption experiments are carried out by Agarwal et al by using SP-RPB, and the results show that the SP-RPB is particularly suitable for mass transfer process of strengthening gas phase resistance control. However, there are some problems with SP-RPB, such as: the rotating radius of the center of the rotor or the part close to the center is small, the gas is difficult to obtain larger tangential speed through the high-speed rotation of the filler, the gas phase turbulence degree is insufficient, the radial distribution is uneven, and the utilization rate of the filler is lower; the filler is directly fixed on the upper and lower turntables by using foam metal, is not suitable for replacement, and is difficult to apply to occasions with large air volume and large liquid volume only depending on the mechanical strength of the foam metal during working.
Patent CN201310402589.3 discloses a "flue gas desulfurization device and technology", the device is a reverse rotation packed bed, the main part includes collection chamber and main cavity room, be equipped with in the main cavity room and can independently rotate last carousel and lower carousel, the packing ring on upper and lower carousel nests each other. The structure of the supergravity device can increase the shear stress of fluid, the filler transfers more momentum to the internal fluid, the separation of a gas-liquid boundary layer is promoted, the turbulence degree is intensified, and the gas-liquid interface updating rate is accelerated, so that the purpose of strengthening gas-phase mass transfer is achieved; the operation stability is improved, and the method is more suitable for occasions with large flux; the gas collecting chamber effectively inhibits the influence of entrainment and flooding on the operation balance. The reverse rotating packed bed has the reverse shearing effect on gas and liquid, so that gas phase mass transfer is enhanced. However, the packing material still belongs to a gas-liquid countercurrent contact mode, which requires that the inner ring size of the packing layer is large enough, the radial size is relatively large, and for a rotor component rotating at high speed, the size increase brings great inconvenience to processing, manufacturing, installation and debugging, and especially, the energy consumption and investment are also greatly increased.
The supergravity enhanced ozone advanced oxidation technology is a novel wastewater treatment technology, and utilizes a supergravity environment created by a filler rotor rotating at a high speed in a cross-flow rotating packed bed to enable liquid to overcome the action of surface tension and move in the rotating packed bed at an extremely high speed and an extremely small size, the filler in the rotor increases the turbulence of the liquid, the mass transfer process of ozone transferred from a gas phase to a liquid phase is enhanced, and the concentration and the oxidation efficiency of the ozone in the liquid phase are effectively improved. The gas contacts with the liquid in a cross flow manner, so that the radial size of the packing layer can be reduced, the flooding is not easy to generate, and the method is particularly suitable for the heat transfer, mass transfer and reaction processes for treating large gas quantity.
The oxidation mechanism of the ozonization method is direct oxidation and indirect oxidation, wherein the former uses ozone to directly oxidize and degrade organic molecules and has selectivity on an action object, and the latter uses the self-decomposition reaction of ozone in wastewater to generate OH and oxidize and degrade pollutants in the wastewater, and the reaction is rapid and has no selectivity on the action object. Therefore, increasing the ability of ozone to generate OH in solution also increases the efficiency of ozonation. It is clear that the hypergravity technique only accelerates the mass transfer rate of ozone to the liquid phase, but does not accelerate the reaction rate of ozone to OH in solution.
The homogeneous catalytic ozonization method is to add metal ion catalyst into the solution to catalyze the ozonolysis and accelerate the generation rate of OH, thereby improving the efficiency of ozonizing and degrading organic wastewater. A commonly used catalyst is Fe2+The initiator is an initiator of a free radical chain reaction, and accelerates the generation rate of ozone and OH. However, the mass transfer process of ozone dissolved in liquid phase is controlled by a liquid membrane and is slow, and the mass transfer process of ozone cannot be accelerated by adding the catalyst, so that the efficiency of the catalyst for ozonizing and degrading wastewater, particularly for degrading high-concentration organic wastewater, is limited in improvement amplitude.
Patent CN112573728A has disclosed an integration iron carbon-fenton coupling catalytic oxidation reactor and waste water treatment method, utilize telescopic inner tower, outer tower structure to make little electrolytic reactor of iron carbon and fenton catalytic oxidation reactor realize the integration, can make little electrolytic reaction of iron carbon and fenton catalytic oxidation reaction can independently go on simultaneously again, the difficult problem that solution stirring is mixed has been solved, avoid the problem of the catalyst consumption that the aeration stirring leads to simultaneously, be favorable to improving fenton reaction efficiency. However, the method and the device do not solve the problem of passivation hardening of the iron-carbon filler in iron-carbon micro-electrolysis.
Disclosure of Invention
The reaction device and the method for treating nitrobenzene wastewater by integrated reinforced iron-carbon microelectrolysis-ozone coupling are used for solving the problems of filler passivation inactivation, blocked electrolytic reaction, reduced iron-carbon microelectrolysis efficiency, limited ozone oxidation capacity and low utilization rate after an iron-carbon microelectrolysis bed in the prior art runs for a long time, simplifying process procedures, saving wastewater treatment cost, and simultaneously effectively avoiding Fe by the integrated reaction device2+Is wasted.
In order to achieve the purpose, the invention provides an integrated reaction device for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling, which comprises an oxygen cylinder, an ozone generator, a rotary packed bed, a pump and a nitrobenzene wastewater reservoir, wherein a circular rotor is rotatably arranged in the rotary packed bed; the rotor is sequentially provided with a rotor outer shell, an annular partition plate and a rotor inner shell from outside to inside, through holes are formed in the rotor outer shell, the annular partition plate and the rotor inner shell, a metal wire mesh made of metal wire coils is filled between the rotor outer shell and the annular partition plate, and iron carbon balls are stacked between the annular partition plate and the rotor inner shell; a gap between the rotor shell and the rotating packed bed shell is filled with liquid to form a liquid seal when the rotor rotates; the rotary packed bed is provided with an air inlet, an air outlet, a liquid inlet and a liquid outlet; the nitrobenzene wastewater reservoir is connected with a pump, the pump is connected with a liquid inlet of the rotary packed bed, and nitrobenzene wastewater flows into the rotor inner shell from the top of the rotor inner shell and sequentially passes through the rotor inner shell, the iron-carbon balls, the annular partition plate, the metal wire mesh and the rotor outer shell; the oxygen cylinder is connected with the ozone generator, the ozone generator is connected with the air inlet of the rotary packed bed, and the ozone flows in from the bottom of the metal wire mesh and flows out from the top.
Furthermore, the annular partition plate and the bottom of the rotor inner shell are additionally provided with a baffle plate to serve as an iron carbon ball support, and the bottom of the rotor outer shell and the bottom of the annular partition plate are additionally provided with a support rib to serve as a metal wire mesh support.
Furthermore, a liquid distributor is arranged in the rotor inner shell, a plurality of liquid outlet holes are formed in the liquid distributor, and a liquid inlet of the liquid distributor is connected with a liquid inlet of the rotary packed bed.
Furthermore, the liquid outlet holes are spirally arranged.
Further, the rotor is driven by a variable frequency motor.
Further, a liquid outlet of the rotary packed bed is connected with a nitrobenzene wastewater liquid storage tank.
Further, the gas outlet of the rotary packed bed is connected with a tail gas absorption device.
Further, a gas flowmeter is arranged between the ozone generator and the rotary packed bed; a liquid flowmeter is arranged between the pump and the rotary packed bed.
Furthermore, a leading-out pipeline between the ozone generator and the gas flowmeter is connected with a gas inlet of the ozone concentration detector, and a gas outlet of the ozone concentration detector is connected with the ozone tail gas treatment device.
The invention also provides a method for treating nitrobenzene wastewater by strengthening iron-carbon microelectrolysis-ozone coupling, which comprises the following steps:
the nitrobenzene wastewater is put into the reactionIn a rotating packed bed in the device, nitrobenzene difficult to degrade is reduced into aniline easy to degrade under the condition of supergravity through the electrolysis of iron-carbon micro-electrolysis, and simultaneously a large amount of Fe is generated after the electrolysis reaction2+Releasing into the wastewater; fe carried by waste water2+Throwing the sewage into a wire mesh in a rotor, contacting with ozone in a cross flow manner, fully reacting, and deeply oxidizing and degrading organic matters in the wastewater.
Specifically, the initial concentration of the nitrobenzene compound in the wastewater is 200-400mg/L, and the pH value is 1; the volume of the iron-carbon spheres in the rotating packed bed is 400 mL, and the content ratio of iron to carbon is 5: 1, the rotation speed of a rotor is 800-1000 rpm, the liquid-gas ratio of the wastewater to the ozone is 0.8-1.5L/L, the concentration of the ozone is 30-40mg/L, the liquid inlet speed of a liquid inlet is 80L/h, and the wastewater is circularly treated in a rotating packed bed for 60 min.
The invention has the following advantages:
(1) iron-carbon microelectrolysis and hypergravity-catalytic ozonization method are coupled and used for treating nitrobenzene wastewater, on one hand, the iron-carbon microelectrolysis is firstly adopted to reduce nitrobenzene into aniline, so that the subsequent ozonization method is convenient to deeply oxidize and degrade the wastewater, and on the other hand, Fe generated by the microelectrolysis reaction is utilized2+As the catalyst of the ozonization method, the zero addition of the catalyst required by the subsequent hypergravity-ozonization method is realized;
(2) enough catalyst Fe is provided for the subsequent hypergravity-ozonization method to ensure the iron-carbon micro-electrolysis reaction energy2+The integrated reaction device for treating the nitrobenzene wastewater by the coupling of the iron-carbon micro-electrolysis and the ozone is adopted, and the liquid is sheared by the filler rotating at a high speed, so that the solid-liquid and gas-liquid two-phase interfacial area is continuously updated, and the high reaction rate of the iron-carbon micro-electrolysis and the high utilization rate of the ozone are ensured;
(3) the reaction rate of iron-carbon micro-electrolysis is improved by 2-3 times on the whole due to the intervention of supergravity, and free Fe in wastewater is enabled to be generated2+The concentration is improved by 6-10 times, and the ozone dosage of a subsequent hypergravity-ozonization method is greatly reduced.
Drawings
FIG. 1 is a schematic structural diagram of a reaction device for treating nitrobenzene wastewater by integrated reinforced iron-carbon microelectrolysis-ozone coupling;
fig. 2 is a schematic structural view of the rotor.
In the figure: 1-an oxygen cylinder; 2-an ozone generator; 3-a gas flow meter; 4-an ozone tail gas treatment device; 5-an ozone concentration detector; 6-rotating the packed bed; 7-a rotor; 7.1-rotor housing; 7.2-annular partition; 7.3-inner rotor shell; 7.4-wire mesh; 7.5-iron carbon spheres; 8-a variable frequency motor; 9-a centrifugal pump; a 10-nitrobenzene waste water reservoir; 11-tail gas absorption device.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
The embodiment provides an integrated reaction device for treating nitrobenzene wastewater by strengthening iron-carbon microelectrolysis-ozone coupling, which comprises an oxygen cylinder 1, an ozone generator 2, a rotary packed bed 6, a centrifugal pump 9 and a nitrobenzene wastewater reservoir tank 10, wherein a circular rotor 7 is rotatably arranged in the rotary packed bed 6; the rotor 7 is sequentially provided with a rotor outer shell 7.1, an annular partition plate 7.2 and a rotor inner shell 7.3 from outside to inside, through holes are formed in the rotor outer shell 7.1, the annular partition plate 7.2 and the rotor inner shell 7.3, and a wire mesh 7.4 made of a metal wire coil is filled between the rotor outer shell 7.1 and the annular partition plate 7.2 to form an oxidation area; iron-carbon balls 7.5 are stacked between the annular partition plate 7.2 and the rotor inner shell 7.3 to form a reduction region; the gap between the rotor housing 7.1 and the rotating packed bed housing is filled with liquid to form a liquid seal when the rotor 7 rotates, so that ozone is prevented from passing through the gap between the rotor housing and the rotating packed bed housing; the rotary packed bed 6 is provided with an air inlet, an air outlet, a liquid inlet and a liquid outlet; the nitrobenzene wastewater reservoir 10 is connected with a centrifugal pump 9, the centrifugal pump 9 is connected with a liquid inlet of the rotary packed bed 6, and nitrobenzene wastewater flows into the rotor inner shell 7.3 from the top of the rotor inner shell 7.3 and sequentially passes through the rotor inner shell 7.3, the iron-carbon balls 7.5, the annular partition plate 7.2, the metal wire mesh 7.4 and the rotor outer shell 7.1 (shown by oblique line arrows in figure 2); the oxygen cylinder 1 is connected with the ozone generator 2, the ozone generator 2 is connected with the air inlet of the rotary packed bed 6, and the ozone flows into the top from the bottom of the wire mesh 7.4 and flows out (shown by hollow arrows in figure 2).
Furthermore, a liquid distributor is arranged in the rotor inner shell 7.3, a plurality of liquid outlet holes are formed in the liquid distributor, and a liquid inlet of the liquid distributor is connected with a liquid inlet of the rotary packed bed 6.
Further, the liquid outlet holes are spirally arranged, and the diameter of each liquid outlet hole is 2-3 mm.
Further, the rotor 7 is driven by a variable frequency motor 8.
Further, a liquid outlet of the rotating packed bed 6 is connected with a nitrobenzene waste water storage tank 10.
Further, the gas outlet of the rotating packed bed 6 is connected with a tail gas absorption device 11.
Further, a gas flow meter 3 is arranged between the ozone generator 2 and the rotating packed bed 6.
Further, a leading-out pipeline between the ozone generator 2 and the gas flowmeter 3 is connected with a gas inlet of an ozone concentration detector 5, and a gas outlet of the ozone concentration detector 5 is connected with an ozone tail gas treatment device 4.
Specifically, the inner diameter of the rotor 7 is 60mm, the outer diameter is 360mm, the height is 30mm, the width of the reduction region is 150mm, the width of the oxidation region is 150mm, the annular partition plate 7.2 is an iron plate with the thickness of 2-3mm, holes are formed in the iron plate every 5mm, the diameter of each hole is 1-2mm, the bottom of the annular partition plate 7.2 and the bottom of the rotor inner shell 7.3 are additionally provided with a baffle plate to serve as an iron carbon ball 7.5 support, and the bottom of the rotor outer shell 7.1 and the bottom of the annular partition plate 7.2 are additionally provided with a support rib to serve as a metal wire mesh support 7.4. The diameter of the iron-carbon ball 7.5 is 2-3cm, the iron-carbon ratio is 5: 1. the gap between the rotor housing 7.1 and the rotating packed bed housing is 3 mm.
The rotating packed bed in this example is not described in part as the disclosed technology, and refer to CN91109255.2 rotating bed supergravity field enhanced transfer and reaction device, CN200520100685.3 multi-layer baffled supergravity rotating bed device.
Example 2
The embodiment provides a method for treating nitrobenzene wastewater by an enhanced iron-carbon microelectrolysis-catalytic ozonation method, which comprises the following steps of:
the method for treating nitrobenzene wastewater by strengthening iron-carbon microelectrolysis-ozone coupling comprises the following steps:
the nitrobenzene wastewater is put into a rotating packed bed 6 in the reaction device, so that nitrobenzene difficult to degrade is reduced into aniline easy to degrade under the super-gravity environment through the electrolysis of iron-carbon micro-electrolysis, and simultaneously a large amount of Fe is generated after the electrolysis reaction2+Releasing into the wastewater; fe carried by waste water2+Thrown into a wire mesh 7.4 in a rotor 7, and contacts with ozone in a cross flow manner to fully react and deeply oxidize and degrade organic matters in the wastewater.
The specific process is as follows: the nitrobenzene wastewater in the nitrobenzene wastewater reservoir 10 is pumped into a rotor 7 loaded with iron carbon balls 7.5 and a wire mesh 7.4 by a centrifugal pump 9, a variable frequency motor 8 of a rotary packed bed 6 is started, oxygen in an oxygen bottle 1 enters an ozone generator 2 to generate ozone, the ozone enters the rotary packed bed 6 through a gas flowmeter 3 and carries a large amount of Fe2+The wastewater is contacted with ozone in a cross flow manner on the metal wire mesh 7.4 and reacts, the wastewater after the reaction flows back to the nitrobenzene wastewater reservoir 10 again, and is continuously sent to the rotor 7 loaded with the iron-carbon balls 7.5 and the metal wire mesh 7.4 by the centrifugal pump 9 for circular treatment.
Before use, the rotor 7 is washed for 30min by using sulfuric acid with pH of 3 to remove the metal oxide film on the surface of the iron-carbon ball 7.5.
When the traditional iron-carbon micro-electrolysis method is used for directly treating wastewater, a metal oxide layer is easily formed on the iron surface to coat reactive active sites on the surface of a filler, so that the iron-carbon micro-electrolysis reaction is hindered, and simultaneously Fe generated by micro-electrolysis2+Can be hydrolyzed to generate Fe (OH) with coagulation effect2And Fe (OH)3Forming stable flocculate in the solution, wherein the flocculate is gradually deposited on the surface of the iron-carbon filler to block the micro-electrolysis electron transfer process of the iron-carbon and absorbs and carries away partial free Fe2+Reduction of Fe in solution2+Concentration of Fe which results in the catalyst required for the subsequent catalytic ozonation process2+The supply is insufficient. Therefore, the traditional iron-carbon micro-electrolysis bed has the problems that the filler is easy to passivate and deactivate and is difficult to continuously operate for a long time. Book (I)In the embodiment, the rotor 7 in the rotating packed bed 6 rotates at a high speed to generate a centrifugal force field, so that the supergravity is obtained, and the problem of easy passivation of iron-carbon packing can be solved.
The traditional hypergravity intensified ozonization method mainly utilizes the characteristic of the hypergravity equipment for intensifying mass transfer to greatly improve the concentration of dissolved ozone in solution, but does not accelerate the reaction rate of ozone generation and OH, so that a catalyst Fe is often added during the actual wastewater treatment2+The ozone decomposition is catalyzed, the generation rate of OH is accelerated, the ozone dissolved in the solution is fully utilized, and the oxidation efficiency is improved. Moreover, due to the strong electron-withdrawing effect of the nitro group, the chemical properties of nitrobenzene are relatively stable, and the nitrobenzene is difficult to be completely degraded quickly by adopting a direct oxidation method, so that the time consumption is long, and the treatment cost of wastewater is increased. The nitrobenzene wastewater is treated by coupling two-stage process of hypergravity-enhanced iron-carbon micro-electrolysis and catalytic ozonization, so that iron-carbon micro-electrolysis can be utilized to activate benzene rings, nitrobenzene which is difficult to degrade is converted into aniline, the subsequent time of ozone deep degradation is saved, the ozone consumption is reduced, and a large amount of Fe can be dissolved in wastewater subjected to iron-carbon micro-electrolysis2+The catalyst is used for catalyzing ozone decomposition to generate OH, and the reaction mechanism is shown as a formula 6-13.
Fe2+ + O3 → Fe3+ +
Figure 553138DEST_PATH_IMAGE002
O3 -(formula 6)
Figure 21291DEST_PATH_IMAGE002
O3 -+ H+ → O2 OH (formula 7)
Fe2+ + O3 → FeO2+ + O2 (formula 8)
FeO2+ + H2O → Fe3+ + ·OH + OH- (formula 9)
Fe3+ + O3 + H2O → FeO2+ + O2 +·OH + H+ (formula 10)
2·OH2 → H2O2 + O2 (formula 11)
Fe2+ + H2O2 → Fe3+ + ·OH + OH- (formula 12)
Fe3+ + H2O2 → Fe2+ + H+ + ·OH2 (formula 13)
By adopting the method of the embodiment, (1) nitrobenzene can be reduced into aniline with active chemical property by using iron-carbon micro-electrolysis in a reduction zone, and then ozone deep oxidation degradation is carried out; (2) iron-carbon micro-electrolysis provides catalyst Fe for catalytic ozonization method2+The ozonization efficiency is improved; (3) the application of the supergravity technology ensures the free Fe in the micro-electrolysis effluent2+Is higher in concentration, and provides enough catalyst Fe for catalyzing ozone in the oxidation zone to degrade aniline2+The whole process is realized without adding catalyst Fe separately2+And reducing the ozone consumption.
Example 3
Nitrobenzene wastewater was treated using the apparatus shown in figure 1. The initial concentration of nitro compounds in the wastewater was 200 mg/L, with a pH of 1. The volume of the iron-carbon spheres in the reduction zone is 7.5 mL, the iron-carbon content ratio is 5: 1, rotating the variable frequency motor 8 of the packed bed 6 at 800 rpm, adjusting the gas flowmeter 3 to ensure that the liquid-gas ratio of the wastewater to the ozone is 1.5L/L and the ozone concentration is 30 mg/L. 2L of nitrobenzene wastewater is placed in a nitrobenzene wastewater reservoir 10, and is circularly treated in a rotating packed bed 6 for 60 min by a centrifugal pump 9 at a flow rate of 80L/h, wherein the removal rate of nitrobenzene is 100 percent, and the mineralization rate is 80 percent.
The wastewater is treated by directly utilizing the micro-electrolysis-hypergravity-catalytic ozonation method without using a hypergravity technology, and the treatment time of the wastewater is prolonged by 3 times and the dosage of ozone is increased by 2 times when the same treatment effect is achieved under the same operation condition and the same treatment capacity is unchanged.
Example 4
Nitrobenzene wastewater was treated using the apparatus shown in figure 1. The initial concentration of nitro compound in the wastewater was 400mg/L and the pH was 1. The volume of the iron-carbon spheres in the reduction zone is 7.5 mL, the iron-carbon content ratio is 5: 1, rotating the frequency conversion motor 8 of the packed bed 6 at 1000 rpm, adjusting the gas flowmeter 3 to ensure that the liquid-gas ratio of the wastewater to the ozone is 0.8L/L and the ozone concentration is 40 mg/L. 2L of nitrobenzene wastewater is placed in a nitrobenzene wastewater reservoir 10, and is circularly treated in a rotating packed bed 6 for 60 min by a centrifugal pump 9 at a flow rate of 80L/h, wherein the removal rate of nitrobenzene is 100 percent, and the mineralization rate is 72 percent.
The wastewater is treated by directly utilizing the micro-electrolysis-hypergravity-catalytic ozonation method without using a hypergravity technology, and the treatment time of the wastewater is prolonged by 3 times and the dosage of ozone is increased by 2 times when the same treatment effect is achieved under the same operation condition and the same treatment capacity is unchanged.
The invention is not the best known technology.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. An integrated reaction device for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling comprises an oxygen cylinder, an ozone generator, a rotary packed bed, a pump and a nitrobenzene wastewater reservoir, and is characterized in that a circular rotor is rotatably arranged in the rotary packed bed;
the rotor is sequentially provided with a rotor outer shell, an annular partition plate and a rotor inner shell from outside to inside, through holes are formed in the rotor outer shell, the annular partition plate and the rotor inner shell, a metal wire mesh made of metal wire coils is filled between the rotor outer shell and the annular partition plate, and iron carbon balls are stacked between the annular partition plate and the rotor inner shell;
the gap between the rotor shell and the rotating packed bed shell is filled with liquid to form a liquid seal when the rotor rotates;
the rotary packed bed is provided with an air inlet, an air outlet, a liquid inlet and a liquid outlet;
the nitrobenzene wastewater reservoir is connected with a pump, the pump is connected with a liquid inlet of the rotary packed bed, and nitrobenzene wastewater flows into the rotor inner shell from the top of the rotor inner shell and sequentially passes through the rotor inner shell, the iron carbon balls, the annular partition plate, the metal wire mesh and the rotor outer shell;
the oxygen cylinder is connected with an ozone generator, the ozone generator is connected with an air inlet of the rotary packed bed, and ozone flows into the top of the rotary packed bed from the bottom of the metal wire mesh and flows out of the top of the rotary packed bed.
2. The integrated reinforced iron-carbon microelectrolysis-ozone coupling nitrobenzene wastewater reaction device as claimed in claim 1, wherein the annular partition plate and the bottom of the rotor inner shell are additionally provided with baffle plates as iron-carbon ball supports, and the bottom of the rotor outer shell and the annular partition plate are additionally provided with support ribs as wire mesh supports.
3. The integrated reaction device for treating nitrobenzene wastewater by reinforced iron-carbon microelectrolysis-ozone coupling according to claim 2, wherein a liquid distributor is arranged in the inner shell of the rotor, a plurality of liquid outlet holes are formed in the liquid distributor, and a liquid inlet of the liquid distributor is connected with a liquid inlet of the rotary packed bed.
4. The integrated reinforced iron-carbon microelectrolysis-ozone coupling nitrobenzene wastewater reaction device as recited in claim 3, wherein the liquid outlet holes are spirally arranged;
the rotor is driven by a variable frequency motor.
5. The integrated reinforced iron-carbon microelectrolysis-ozone coupling reaction device for treating nitrobenzene waste water as claimed in claim 4, wherein a liquid outlet of the rotating packed bed is connected with a nitrobenzene waste water storage tank.
6. The integrated reinforced iron-carbon microelectrolysis-ozone coupling reaction device for treating the nitrobenzene wastewater as recited in claim 5, wherein an air outlet of the rotating packed bed is connected with a tail gas absorption device.
7. The integrated reinforced iron-carbon microelectrolysis-ozone coupling reaction device for treating the nitrobenzene wastewater as recited in claim 6, wherein a gas flowmeter is arranged between the ozone generator and the rotary packed bed.
8. The integrated reinforced iron-carbon microelectrolysis-ozone coupling nitrobenzene wastewater reaction device as recited in claim 7, wherein a pipeline is led out between the ozone generator and the gas flowmeter and is connected with a gas inlet of the ozone concentration detector, and a gas outlet of the ozone concentration detector is connected with the ozone tail gas treatment device.
9. A method for treating nitrobenzene wastewater by strengthening iron-carbon microelectrolysis-ozone coupling is characterized by comprising the following steps:
putting the nitrobenzene wastewater into a rotating packed bed in a reaction device as claimed in any one of claims 1 to 8, so that nitrobenzene which is difficult to degrade is reduced into aniline which is easy to degrade under the condition of high gravity through the electrolysis of iron-carbon micro-electrolysis, and a large amount of Fe is generated after the electrolysis reaction2+Releasing into the wastewater; fe carried by waste water2+Throwing the sewage into a wire mesh in a rotor, contacting with ozone in a cross flow manner, fully reacting, and deeply oxidizing and degrading organic matters in the wastewater.
10. The method as claimed in claim 9, wherein the initial concentration of nitrobenzene compound in the wastewater is 200-400mg/L, the pH value is 1;
the volume of the iron-carbon spheres in the rotating packed bed is 400 mL, and the content ratio of iron to carbon is 5: 1, the rotation speed of a rotor is 800-1000 rpm, the liquid-gas ratio of the wastewater to the ozone is 0.8-1.5L/L, the concentration of the ozone is 30-40mg/L, the liquid inlet speed of a liquid inlet is 80L/h, and the wastewater is circularly treated in a rotating packed bed for 60 min.
CN202111621193.9A 2021-12-28 2021-12-28 Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling Pending CN114380430A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111621193.9A CN114380430A (en) 2021-12-28 2021-12-28 Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111621193.9A CN114380430A (en) 2021-12-28 2021-12-28 Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling

Publications (1)

Publication Number Publication Date
CN114380430A true CN114380430A (en) 2022-04-22

Family

ID=81197615

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111621193.9A Pending CN114380430A (en) 2021-12-28 2021-12-28 Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling

Country Status (1)

Country Link
CN (1) CN114380430A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105233765A (en) * 2015-09-23 2016-01-13 中北大学 High-air speed selectively-catalytic unit and method used in hypergravity field
CN106693858A (en) * 2015-07-22 2017-05-24 北京化工大学 Anti-blocking type super gravity rotating bed and system device comprising anti-blocking type super gravity rotating bed and application
US20180280871A1 (en) * 2015-03-30 2018-10-04 Co2 Solutions Inc. Intensification of biocatalytic gas absorption
US20200261846A1 (en) * 2019-02-18 2020-08-20 Research Triangle Institute Rotating packed beds with internal heat transfer for absorption/regeneration applications
CN113754143A (en) * 2021-09-07 2021-12-07 中北大学 Device and method for treating dinitrotoluene wastewater by using reinforced iron-carbon microelectrolysis-catalytic ozonation method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20180280871A1 (en) * 2015-03-30 2018-10-04 Co2 Solutions Inc. Intensification of biocatalytic gas absorption
CN106693858A (en) * 2015-07-22 2017-05-24 北京化工大学 Anti-blocking type super gravity rotating bed and system device comprising anti-blocking type super gravity rotating bed and application
CN105233765A (en) * 2015-09-23 2016-01-13 中北大学 High-air speed selectively-catalytic unit and method used in hypergravity field
US20200261846A1 (en) * 2019-02-18 2020-08-20 Research Triangle Institute Rotating packed beds with internal heat transfer for absorption/regeneration applications
CN113754143A (en) * 2021-09-07 2021-12-07 中北大学 Device and method for treating dinitrotoluene wastewater by using reinforced iron-carbon microelectrolysis-catalytic ozonation method

Similar Documents

Publication Publication Date Title
CN105060419B (en) Multicell multidimensional electro-coagulation equipment for high ammonia-nitrogen wastewater
CN109647315A (en) Super-gravity device, method for oxidation and the system that energy makes full use of
CN104710000B (en) The method and device of catalysis ozone degrading nitrobenzene class waste water in a kind of super gravity field
CN103613169B (en) The device of supergravity multistage sacrificial anode Electro-Fenton process process used water difficult to degradate and technique
CN105858965A (en) Method and device for deep treatment on nitrobenzene wastewater by using supergravity intensifying nano zero-valent iron-ozone method
CN206512041U (en) A kind of device of two-stage gradient ozone catalytic fluidized bed deep treatment biochemical tail water
CN205740573U (en) The device of hypergravity reinforced nano Zero-valent Iron Ozone advanced treating nitrobenzene waste water
CN206858331U (en) Electrode couples ozone oxidation integral reactor
CN112174292B (en) Advanced treatment device and method for printing and dyeing wastewater
CN201592999U (en) Micro electrolyzation waste water processor
CN114380430A (en) Integrated reaction device and method for treating nitrobenzene wastewater by strengthening iron-carbon micro-electrolysis-ozone coupling
CN110668552B (en) Ozone synergistic micro hydrogen peroxide catalytic device and method
CN110668551B (en) Ozone catalytic device and method
CN113754143A (en) Device and method for treating dinitrotoluene wastewater by using reinforced iron-carbon microelectrolysis-catalytic ozonation method
CN107459124A (en) COD method and device in a kind of hydrogen peroxide heterocatalysis oxidized waste water
CN216918935U (en) Membrane concentrate processing system
CN106830457A (en) Electrode couples ozone oxidation integral reactor
CN110255698B (en) Water treatment device and method for strengthening mass transfer and oxidation process of ozone
CN211946421U (en) Three-phase Fenton fluidized bed oxidation system
CN107585852A (en) COD method and device in a kind of ozone heterocatalysis oxidized waste water
CN113816484A (en) Method and apparatus for treating wastewater
CN113087114A (en) Ozone catalytic reactor with underneath catalyst and process thereof
CN206858249U (en) Electrode couples ozone oxidation all-in-one fluidization bed reactor
CN105884092A (en) Method and device for degrading nitrobenzene waste water through reinforced iron-carbon micro-electrolysis-ozonation method
CN219991287U (en) Vertical multi-fold rotary ozone oxidation reactor

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20220422