CN110921832B - High ammonia nitrogen wastewater treatment device and method - Google Patents
High ammonia nitrogen wastewater treatment device and method Download PDFInfo
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- CN110921832B CN110921832B CN201911297099.5A CN201911297099A CN110921832B CN 110921832 B CN110921832 B CN 110921832B CN 201911297099 A CN201911297099 A CN 201911297099A CN 110921832 B CN110921832 B CN 110921832B
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Abstract
The invention discloses a high ammonia nitrogen wastewater treatment device and method, and belongs to the field of sewage treatment. According to the high ammonia nitrogen wastewater treatment device, the aerobic zone is divided into the first aerobic zone taking the decarbonizing bacteria as the dominant flora and the second aerobic zone taking the nitrifying bacteria as the dominant flora through a special structural design, COD (chemical oxygen demand) degradation is carried out in the first aerobic zone, and nitrification and denitrification are carried out in the second aerobic zone, so that the inhibition effect of the decarbonizing bacteria on the nitrifying bacteria is reduced, the nitrification and denitrification effect is improved, the effluent ammonia nitrogen is ensured to reach the standard, and the effluent quality is ensured. The high ammonia nitrogen wastewater treatment device provided by the invention is used for wastewater treatment, and has the advantages of small occupied area, compact structure, wide application range, strong impact resistance, stable effluent quality and the like.
Description
Technical Field
The invention belongs to the field of sewage treatment, and particularly relates to a high ammonia nitrogen wastewater treatment device and method.
Background
Excessive ammonia nitrogen discharged into water body can cause eutrophication of water body, the ornamental value of water body is reduced, and nitrate and nitrite generated by oxidation can influence the health of aquatic organisms and even human beings. Therefore, denitrification of wastewater is receiving much attention.
At present, the main denitrification methods include gas stripping, chemical precipitation, breakpoint chlorine addition, an ion exchange method, biological nitrification and denitrification and the like. The blow-off method is one of the most commonly used methods for treating ammonia nitrogen wastewater at present, and the blow-off method is used for treating ionic ammonium (NH) in the wastewater4+) And is converted into molecular ammonia by adjusting the pH value, and then blown out by introduced air or steam. The main factors influencing the stripping efficiency are as follows: the research on the stripping method mainly focuses on the following steps: stripping equipment (stripping pool, stripping tower), stripping form (natural stripping, blast stripping), packing form (structured packing, Raschig ring)Polypropylene pall ring, etc.) blow-off parameters (pH value, gas-water ratio, blow-off temperature, etc.). The research result shows that: when the pH value is 10-13 and the temperature is 30-50 ℃, the ammonia nitrogen stripping rate is 70.3-99.3%. The waste water from steel-making, petrochemical, chemical fertilizer, organic chemical industry and other industries contains ammonia with very high concentration, so that the waste water is treated by a steam stripping method. The blow-off method is used for the pretreatment of high-concentration ammonia nitrogen wastewater, and has the advantages of stable ammonia removal effect, simple operation and easy control; however, the problems of improving the stripping efficiency, avoiding secondary pollution and controlling the generation of scale in the production process are all considered in the ammonia stripping method.
The chemical precipitation process (MAP process) is carried out in the presence of NH4+Adding Mg into the ionic wastewater2+And PO4 3-Is made to react with NH4+To generate insoluble double salt magnesium ammonium phosphate MgNH4PO4·6H2Crystallizing O (MAP), and separating MAP from waste water by precipitation. The chemical precipitation method is particularly suitable for treating high-concentration ammonia nitrogen wastewater, and has the denitrification efficiency of more than 90 percent. When the waste water has no toxic and harmful substances, the magnesium ammonium phosphate is a good slow-release compound fertilizer required by crops. When the pH value is too high during the treatment, part of NH is easily generated3And (6) volatilizing. MgO and H are generally used as the precipitant3PO4So that not only can other harmful ions be prevented from being brought in, but also MgO can neutralize H+The function of the ions. The research finds that: adding Na when the pH value is 8.62HPO4And MgCl2The ammonia nitrogen can be reduced from 6518mg/L to 65 mg/L. The chemical precipitation method for treating the high-concentration ammonia nitrogen wastewater has simple process and high efficiency. However, the ammonia nitrogen residual concentration in the wastewater is still high; in addition, the amount of the chemical to be added, the passage of the precipitate, and the contamination caused by chlorine ions and phosphorus which are introduced by the chemical addition are problems to be noticed.
The breakpoint chlorination is a process in which chlorine gas is passed into the wastewater to a point where the free chlorine content in the water is at a minimum and the concentration of ammonia is reduced to zero. The treatment efficiency of the chlorination method reaches 90% -100%, but the operation cost is high, and secondary pollution is caused by chloramine and chlorinated organic compounds which are byproducts. And the chlorination process is not suitable for treating high-concentration ammonia nitrogen wastewater.
The ion exchange method adopts zeolite with strong selectivity to ions as exchange resin, thereby achieving the purpose of removing ammonia nitrogen. But for high-concentration ammonia nitrogen wastewater, the operation is difficult due to frequent regeneration of resin. The ion exchange method has high removal rate but high operation cost, and the regenerated liquid is high-concentration ammonia nitrogen wastewater and still needs to be further treated.
The basic principle of the membrane method ammonia nitrogen removal ammonia water recovery technology is to divide waste water into two parts: one is a high-concentration ammonia nitrogen removal process section, and the other is a low-ammonia nitrogen removal process section; high concentrated ammonia is removed first, and then low ammonia is removed. The high-concentration ammonia is converted into high-concentration ammonia water (the ammonia water can be recycled) through an ammonia recovery device, and the wastewater after deamination is discharged into a low-ammonia nitrogen removal process section. In the low ammonia nitrogen removal process section, the low ammonia is converted into an ammonium-containing solution after being absorbed by dilute acid, and the ammonium-containing solution is returned to the high ammonia nitrogen removal process section after further adding alkali to remove ammonia nitrogen and recover ammonia water. After passing through the low ammonia nitrogen removal process section, the ammonia nitrogen in the wastewater can reach the discharge index. The ammonia recovery device adopts a composite technology of vacuum membrane distillation technology and pressurization condensation to form ammonia water. However, the investment cost of the membrane is too high, and the requirement on the water quality of the wastewater is too high, especially on the salinity and the like.
The biological nitrification and denitrification method is the most widely applied denitrification technology at present, and has the advantages of thorough degradation of ammonia nitrogen and low operation cost. However, in the conventional nitrification method, ammonia nitrogen in the wastewater is finally oxidized to generate nitrate under the action of aerobic bacteria, and the process is called nitrification reaction. The reaction is as follows:
2NH4++3O2→2NO2-+4H++2H2O
2NO2-+O2→2NO3-
the overall reaction formula is:
NH4++2O2→NO3-+2H++H2O
the preposed denitrification process A/O initiated in the early 80 s of the last century quickly becomes an important biological denitrification process by virtue of simple flow and low requirements on carbon source and alkalinity.
However, in the aerobic tank, the decarbonizing bacteria are heterotrophic microorganisms, the nitrifying bacteria are autotrophic microorganisms, and the biomass growth coefficient of the autotrophic microorganisms is much lower (about one fifth) than that of the heterotrophic microorganisms, so that in an aerobic system with organic matters as main components, the decarbonizing bacteria are dominant bacteria, the nitrifying bacteria are weak bacteria, the nitrifying bacteria are inhibited, the nitrification reaction is slow or does not occur, and the phenomenon that the aerobic tank does not denitrify is caused.
In addition, the sludge age of the nitrifying bacteria is long, and when the sludge age of the system is lower than the minimum sludge age of the nitrifying bacteria (the minimum sludge age of the nitrifying bacteria exists for sewage under different conditions), the system does not generate nitrification reaction. In the high ammonia nitrogen wastewater treatment system, too high ammonia nitrogen and other pollutants in the wastewater have inhibiting effects on microorganisms to different degrees, so that the microorganism activated sludge of the wastewater treatment system easily loses activity and dies, the sludge concentration of the whole biochemical system is low, the sludge age is low, the biomass of nitrifying bacteria is small, the nitrification reaction of the biochemical system is slow or does not occur, and the phenomenon that the aerobic tank does not denitrify is also caused.
Therefore, compared with decarbonization bacteria, nitrobacteria in the aerobic tank are weak groups, the growth rate of the nitrobacteria is low, the proliferation speed of the bacteria is slow, the generation time of the nitrobacteria is long, the higher biological concentration is difficult to maintain, and particularly in low-temperature winter, the condition that effluent ammonia nitrogen does not reach the standard frequently occurs in operation.
Disclosure of Invention
1. Problems to be solved
Aiming at the problems of low denitrification efficiency, substandard effluent ammonia nitrogen and the like in biological denitrification treatment in the prior sewage treatment technology, the invention provides a high ammonia nitrogen wastewater treatment device and method. According to the high ammonia nitrogen wastewater treatment device, the aerobic zone is divided into the first aerobic zone taking the decarbonizing bacteria as the dominant flora and the second aerobic zone taking the nitrifying bacteria as the dominant flora through a special structural design, COD (chemical oxygen demand) degradation is carried out in the first aerobic zone, and nitrification and denitrification are carried out in the second aerobic zone, so that the inhibition effect of the decarbonizing bacteria on the nitrifying bacteria is reduced, the nitrification and denitrification effect is improved, the effluent ammonia nitrogen is ensured to reach the standard, and the effluent quality is ensured.
2. Technical scheme
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the invention relates to a high ammonia nitrogen wastewater treatment device, which comprises a biological reaction area and a separation area, wherein: the biological reaction zone is characterized in that an air inlet and a water inlet are formed in the top of the biological reaction zone, a central cylinder is arranged in the biological reaction zone, the cross section of the top of the central cylinder is gradually increased from bottom to top, the ratio of the lower cross section to the upper cross section is 1: 1-1: 4, an aeration device and a water distributor are arranged in the central cylinder, the air inlet is connected with the aeration device through an air inlet pipeline, and the water inlet is connected with the water distributor through a water inlet pipeline;
a first aerobic zone is formed between the top of the central cylinder and the aeration device, a second aerobic zone is formed between the top of the biological reaction zone and the outside of the central cylinder, a first opening is formed in the bottom of the central cylinder, and an anoxic zone is formed between the first opening and the aeration device;
the separation area is provided with a second opening below, the separation area is communicated with the biological reaction area through the second opening, the top of the separation area is provided with a water outlet used for discharging treated water, and the bottom of the separation area is provided with a sludge outlet.
The high ammonia nitrogen wastewater treatment device also comprises a sludge activation area, wherein a third opening is arranged above the sludge activation area, the sludge activation area is communicated with the biological reaction area through the third opening, a flow impeller is arranged at the third opening and used for pushing activated sludge into the biological reaction area from the sludge activation area, a sludge inlet is arranged at the bottom of the sludge activation area, and the sludge inlet is connected with a sludge outlet of the separation area through a pipeline.
Preferably, the aeration device and the water distributor are positioned in the middle of the interior of the central cylinder.
Preferably, the volume ratio of the first aerobic zone to the second aerobic zone is 2: 3-3: 2.
preferably, a medicine inlet is formed in the bottom of the sludge activation zone and used for adding a medicine to the sludge activation zone.
Preferably, the sludge activation zone comprises a first pore plate, a second pore plate and a third pore plate, the first activation zone is formed between the first pore plate and the bottom of the sludge activation zone, the second activation zone is formed between the first pore plate and the second pore plate, the third activation zone is formed between the second pore plate and the third pore plate, and the fourth activation zone is formed between the third pore plate and the top of the sludge activation zone, wherein the second activation zone is filled with a filler.
Preferably, the pore diameter of the first pore plate and the pore diameter of the third pore plate are smaller than the particle diameter of the filler, and the pore diameter of the second pore plate is larger than the particle diameter of the filler.
Preferably, an air inlet device is arranged in the third activation zone.
Preferably, the aperture of the first pore plate is 20-30 mm, the aperture of the second pore plate is 90-100 mm, the aperture of the third pore plate is 20-30 mm, and the particle size of the filler is 50-60 mm.
The invention relates to a high ammonia nitrogen wastewater treatment method, which adopts the high ammonia nitrogen wastewater treatment device to treat wastewater and comprises the following specific steps:
s10, enabling the sewage A to upwards enter a central cylinder of a biological reaction zone through a water distributor, starting an aeration device, and carrying out aerobic COD removal on the sewage A in a first aerobic zone to obtain sewage B with COD removed;
s20, making the sewage B flow out of the central cylinder and downwards enter a second aerobic zone, and carrying out aerobic nitrification in the second aerobic zone to obtain sewage C;
s30, enabling the sewage C to upwards enter an anoxic zone through a first opening at the bottom of the central cylinder, and carrying out anoxic denitrification in the anoxic zone to obtain sewage D;
s40, the sewage D flows out of the central cylinder, upwards enters the separation area through the second opening, the sludge and the water body are separated in the separation area, the water body after the sludge is separated is discharged through the water outlet, and the sludge is deposited at the bottom of the separation area and is discharged from the sludge outlet.
Preferably, the method for treating high ammonia nitrogen wastewater further comprises the following steps:
s50, enabling sludge discharged from the sludge outlet to enter the sludge activation area through the sludge inlet through a pipeline, adding a medicament into the sludge activation area through a medicament inlet formed in the bottom of the sludge activation area to activate the sludge, and enabling the activated sludge after treatment to circularly enter the biological reaction area through a third opening.
Preferably, the agent is a carbon source, or a combination of a carbon source and one or both of a biological agent or a coagulant.
3. Advantageous effects
Compared with the prior art, the invention has the beneficial effects that:
(1) according to the high ammonia nitrogen wastewater treatment device, the aeration device is arranged in the central cylinder, so that an aerobic environment mainly comprising decarbonization bacteria is formed in the central cylinder; the water treated by the central cylinder enters the outside of the central cylinder, and an aerobic environment mainly comprising nitrobacteria is formed outside the central cylinder by utilizing residual dissolved oxygen; as the dissolved oxygen is gradually consumed by the nitrification reaction, an anoxic environment is formed between the first opening arranged at the bottom of the central cylinder and the aeration device, and denitrification is performed to complete denitrification; in the whole wastewater treatment process, the aerobic zone is divided into two zones (a first aerobic zone mainly containing decarbonization bacteria and a second aerobic zone mainly containing nitrifying bacteria), so that the nitrifying bacteria can become dominant bacteria, the nitrification capability is fully exerted, and the nitrifying bacteria are not inhibited by the decarbonization bacteria;
(2) according to the high ammonia nitrogen wastewater treatment device, the cross section of the central cylinder is gradually increased from bottom to top, sewage flows upwards after coming out of the water distributor and flows into a region with a large cross section of the central cylinder, the flow rate is reduced due to constant flow, most of sludge in the sewage can fall back into the central cylinder and does not overflow the central cylinder along with water flow, and therefore a COD removal area with high sludge concentration, high aeration amount and full mixed contact of sludge and water is formed in the central cylinder;
(3) the sludge activation zone comprises a first pore plate, a second pore plate and a third pore plate, wherein a first activation zone is formed between the first pore plate and the bottom of the sludge activation zone, a second activation zone is formed between the first pore plate and the second pore plate, a third activation zone is formed between the second pore plate and the third pore plate, and a fourth activation zone is formed between the third pore plate and the top of the sludge activation zone, wherein the second activation zone is filled with filler; the aperture of the first pore plate and the aperture of the third pore plate are smaller than the particle size of the filler, and the aperture of the second pore plate is larger than the particle size of the filler; the arrangement is such that in the first activation zone, the entering sludge is mixed with the added medicament to obtain sludge mixed with the medicament; then the sludge mixed with the medicament is gradually attached to the filler in the second activation zone, and grows into a thicker and thicker biological membrane on the filler, and the filler is trapped between the second activation zone and the third activation zone because the aperture of the second pore plate is larger than the particle size of the filler and the aperture of the first pore plate and the aperture of the third pore plate are smaller than the particle size of the filler; the plug flow device is opened, the biological membrane on the filler can fall off along with water flow by utilizing the hydraulic scouring effect, enters the fourth activation area and enters the second aerobic area of the biological reaction area along with the plug flow device, the sludge concentration in the second aerobic area is increased, the sludge age is prolonged, the nitrification capacity of the reactor is enhanced, and the ammonia nitrogen removal capacity is improved;
(4) the invention relates to a high ammonia nitrogen wastewater treatment method, which comprises the steps of circularly entering sludge in a sludge activation zone for sludge activation after the sludge in a biological reaction zone is precipitated in a separation zone, and then entering the activated sludge into the biological reaction zone again, so that the activated sludge in a system is kept as much as possible, the sludge loss is avoided, meanwhile, the sludge can be activated regularly, the toxic action of high ammonia nitrogen wastewater on the sludge is reduced, the sludge concentration, the sludge age and the microbial biomass in the biological reaction zone are improved, the biomass of nitrifying bacteria is improved, and the nitration reaction is enhanced.
(5) The method for treating the high-ammonia nitrogen wastewater has the advantages of high sludge concentration, strong sludge activity and high system volume load, is suitable for the high-concentration wastewater with small water volume, and can solve the problem that the biomass of the high-concentration wastewater is easy to reduce.
Drawings
FIG. 1 is a schematic structural diagram of a high ammonia nitrogen wastewater treatment device of the invention;
in the figure:
100. a biological reaction zone; 101. an air inlet; 102. a water inlet;
110. a central barrel; 111. an aeration device; 112. a water distributor; 113. a first opening;
120. a first aerobic zone; 130. a second aerobic zone; 140. an anoxic zone;
200. a separation zone; 201. a second opening; 202. a water outlet; 203. a sludge outlet;
300. a sludge activation zone; 301. a third opening; 302. a flow impeller;
303. a sludge inlet; 304. a medicine inlet;
310. a first orifice plate; 311. a first activation zone; 320. a second orifice plate;
321. a second activation region; 330. a third orifice plate; 331. a third activation zone;
332. an air intake device; 341. a fourth activation zone.
Detailed Description
The invention is further described with reference to specific examples.
The invention relates to a high ammonia nitrogen wastewater treatment device, which comprises a biological reaction zone 100, a separation zone 200 and a sludge activation zone 300, wherein the biological reaction zone 100 is arranged between the separation zone 200 and the sludge activation zone 300, and the device comprises:
the top of the biological reaction zone 100 is provided with an air inlet 101 and a water inlet 102, a central cylinder 110 is arranged in the biological reaction zone 100, the cross section of the top of the central cylinder 110 is gradually increased from bottom to top, the ratio of the lower cross section to the upper cross section is 1: 1-1: 4, an aeration device 111 and a water distributor 112 are arranged in the central cylinder 110, the air inlet 101 is connected with the aeration device 111 through an air inlet pipeline, and the water inlet 102 is connected with the water distributor 112 through a water inlet pipeline;
a first aerobic zone 120 is formed between the top of the central cylinder 110 and the aeration device 111, and a second aerobic zone 130 is formed between the top of the biological reaction zone 100 and the outside of the central cylinder 110; the bottom of the central cylinder 110 is provided with a first opening 113, and an anoxic zone 140 is formed between the first opening 113 and the aeration device 111;
it should be noted that the positions of the aeration device 111 and the water distributor 112 in the central cylinder 110 can be determined according to the amount of the influent pollutants, so that the volume ratio of the first aerobic zone to the second aerobic zone is 2: 3-3: 2, ensuring that the first aerobic zone has enough volume to degrade COD and the second aerobic zone has enough volume to nitrify.
Preferably, the aeration device 111 and the water distributor 112 are located in the middle of the interior of the central cylinder 110, so that the height between the water surface in the central cylinder and the aeration device 111 and the water distributor 112 is only half of the height of the central cylinder 110, the lift of a fan can be greatly reduced, the problem of high aeration energy consumption of a reaction device with a large height-diameter ratio is solved, the aeration device 111 and the water distributor 112 are arranged at the same position, aeration treatment of the inlet water from the water distributor 112 is facilitated in time, and the reaction efficiency is improved.
It should be further noted that, by arranging the aeration device 111 in the central cylinder 110 and gradually increasing the cross section of the top of the central cylinder 110 from bottom to top, the inflow water flows out of the water distributor 112 and then enters the large-radius area of the top of the central cylinder 110, the flow rate is reduced due to the constant flow rate, most of the sludge in the water can fall back into the central cylinder 110, so that an aerobic environment mainly comprising decarbonization bacteria is formed in the central cylinder 100; the water treated by the central cylinder 110 enters the outside of the central cylinder 110, and the residual dissolved oxygen is utilized outside the central cylinder 110 to form an aerobic environment mainly comprising nitrobacteria; as the nitrification reaction gradually consumes dissolved oxygen, an anoxic environment is formed at the rear half of the central cylinder 110, and denitrification occurs to complete denitrification. By dividing the aerobic zone into two zones (a first aerobic zone mainly containing decarbonizing bacteria and a second aerobic zone mainly containing nitrifying bacteria), the nitrifying bacteria can become dominant bacteria, and the nitrification capability is fully exerted without being inhibited by the decarbonizing bacteria.
In addition, a second opening 201 is arranged below the separation area 200, the separation area 200 is communicated with the biological reaction area 100 through the second opening 201, a water outlet 202 is arranged at the top of the separation area 200 for discharging treated effluent, and a sludge outlet 203 is arranged at the bottom of the separation area 200;
it should be noted that, the muddy water treated by the biological reaction zone 100 enters the separation zone 200 through the second opening 201, because the water outlet 202 of the separation zone 200 is at a high position, and the depth of the separation zone 200 is enough (generally 6m to 20m), the muddy water can be fully separated in the separation zone 200, the supernatant flows out from the water outlet 202 of the separation zone 200, the separated sludge settles at the bottom of the separation zone, and can enter the sludge activation zone 300 along with the sludge outlet 203;
the bottom of the sludge activation zone 300 is provided with a sludge inlet 303, the sludge inlet 303 is connected with the sludge outlet 203 of the separation zone 200 through a pipeline, and the sludge separated by the separation zone 200 enters the sludge activation zone 300 through the sludge inlet 303; a medicine inlet 304 is further formed in the bottom of the sludge activation zone 300, and a medicine can be added into the sludge activation zone 300 through the medicine inlet 304, wherein the medicine is a carbon source or a combination of the carbon source and one or two of a biological agent or a coagulant;
a third opening 301 is arranged above the sludge activation zone 300, the sludge activation zone 300 is communicated with the biological reaction zone 100 through the third opening 301, and a flow impeller 302 is arranged at the third opening 301 for pushing the activated sludge from the sludge activation zone 300 into the biological reaction zone 100;
it should be further noted that the sludge activation zone 300 includes a first orifice plate 310, a second orifice plate 320, and a third orifice plate 330, a first activation zone 311 is formed between the first orifice plate 310 and the bottom of the sludge activation zone 300, a second activation zone 321 is formed between the first orifice plate 310 and the second orifice plate 320, a third activation zone 331 is formed between the second orifice plate 320 and the third orifice plate 330, and a fourth activation zone 341 is formed between the third orifice plate 330 and the top of the sludge activation zone 300, wherein the second activation zone 321 is filled with a filler, preferably a suspension filler; an air inlet device 332 is arranged in the third activation zone 331 for providing air to the sludge activation zone 300 to facilitate sludge activation;
the pore diameters of the first pore plate 310 and the third pore plate 330 are smaller than the particle diameter of the filler, and the pore diameter of the second pore plate 320 is larger than the particle diameter of the filler; preferably, the aperture of the first orifice plate 310 is 20-30 mm, and the hole spacing is less than 50 mm; the aperture of the second pore plate 320 is 90-100 mm, and the pore distance is less than 50 mm; the aperture of the third pore plate 330 is 20-30 mm, and the pore distance is less than 50 mm; the particle size of the filler is 50-60 mm;
in the first activation zone 311, the incoming sludge is mixed with the dosed agent; in the second activation zone 321, the sludge mixed with the chemical agent gradually adheres to the packing and grows into a thicker and thicker biofilm on the packing, and since the hole diameter of the second hole plate 320 is larger than that of the packing, and the hole diameters of the first hole plate 310 and the third hole plate 330 are smaller than that of the packing, the packing is restricted from moving between the second activation zone 321 and the third activation zone 331.
The flow impeller 302 is opened, the mixed liquid in the sludge activation zone 300 is in an upflow flow state, the upflow velocity can reach 0.5m/s-2m/s, the upflow velocity can form a hydraulic scouring action, the biomembrane on the filler is scoured and fallen by the hydraulic scouring action, enters the fourth activation zone 341, and enters the second aerobic zone 130 of the biological reaction zone 100 along with the flow impeller 302, the sludge concentration of the second aerobic zone 130 is increased, the sludge age is prolonged, the nitrification capacity is enhanced, and the ammonia nitrogen removal capacity is improved.
It should be noted that when the sludge concentration in the biological reaction zone 100 is greater than 3000mg/L, the flow rate of the flow pushing device is controlled, and the flow rate in the sludge activation zone 300 is controlled to be less than 0.5 m/s; when the sludge concentration in the biological reaction zone 100 is less than 3000mg/L, the flow rate of the flow pusher is controlled, and the flow rate in the sludge activation zone 300 is controlled to be more than 0.5 m/s.
It should be further noted that when the sludge mixed liquid in the sludge activation zone 300 of the present invention passes through each layer of the perforated plate, the flow velocity is increased due to the reduction of the flow cross section, and after passing through the perforated plate, the flow velocity is reduced again, so that a turbulent flow state is formed, and the transfer and reaction process between the sludge and the agent is enhanced, so that the sludge is more thoroughly activated.
The method for treating the wastewater by adopting the high ammonia nitrogen wastewater treatment device comprises the following steps:
s10, enabling the sewage A to upwards enter the central cylinder 110 of the biological reaction zone 100 through the water distributor 112, starting the aeration device 111, and carrying out aerobic COD removal on the sewage A in the first aerobic zone 120 to obtain sewage B with COD removed;
s20, making the sewage B flow out of the central cylinder 110 and enter the second aerobic zone 130 downwards, and performing aerobic nitrification in the second aerobic zone 130 to obtain sewage C;
s30, enabling the sewage C to upwards enter the anoxic zone 140 through the first opening 113 at the bottom of the central cylinder 110, and carrying out anoxic denitrification in the anoxic zone 140 to obtain sewage D;
s40, enabling the sewage D to flow out of the central cylinder 110, enabling the sewage D to upwards enter the separation area 200 through the second opening 201, separating sludge from a water body in the separation area 200, discharging the water body after separating the sludge through the water outlet 202, depositing the sludge at the bottom of the separation area 200 and discharging the sludge from the sludge outlet 203;
s50, feeding the sludge discharged from the sludge outlet 203 into the sludge activation zone 300 through the sludge inlet 303 through a pipeline, and adding a medicament into the sludge activation zone 300 through the medicament inlet 304, wherein the medicament is a carbon source or a combination of a carbon source and one or two of a biological microbial agent or a coagulant, so that the sludge is activated, and the activated sludge after treatment is circularly fed into the biological reaction zone 100 through the third opening 301 by controlling the flow impeller 302.
Through the high ammonia nitrogen wastewater treatment method, the wastewater can be subjected to the processes of aerobic COD removal, aerobic nitrification and anoxic denitrification continuously in the biological reaction zone to remove pollutants in the water; the treated effluent enters a separation zone, sludge-water separation is completed in the separation zone with enough depth in the tank, supernatant flows away from a water outlet, sludge is settled at the bottom of the separation zone and is circulated to a sludge activation zone for activation treatment, and the activated sludge can enter a biological reaction zone again to improve the sludge concentration and the activated sludge activity of the biological reaction zone. The high ammonia nitrogen wastewater treatment method has the advantages of small occupied area, compact structure, wide application range, strong impact resistance, stable effluent quality and the like.
Example 1
This embodiment adopts a high ammonia-nitrogen concentration effluent treatment plant to carry out waste water treatment. The high ammonia nitrogen wastewater treatment device comprises a biological reaction zone 100, a separation zone 200 and a sludge activation zone 300, wherein the volume ratio of a first aerobic zone 120 to a second aerobic zone 130 in the biological reaction zone 100 is 1:1.5, and the ratio of the lower cross section to the upper cross section at the top of a central cylinder is 1: 1.5.
The method comprises the following steps of pretreating certain food wastewater to obtain wastewater A, wherein the water quality COD is 100-200mg/L, the ammonia nitrogen is 50-60mg/L, the total nitrogen is 60-80mg/L, and the biodegradability B/C of the wastewater is more than 0.4, and the specific treatment steps are as follows:
s10, enabling the sewage A to upwards enter a central cylinder 110 of the biological reaction zone 100 through a water distributor 112, starting an aeration device 111, controlling the oxygen content of the water body to be 2-3mg/L, and carrying out aerobic COD removal on the sewage A in a first aerobic zone 120 to obtain sewage B with COD removed;
s20, making the sewage B flow out of the central cylinder 110 and enter the second aerobic zone 130 downwards, and carrying out aerobic nitrification in the second aerobic zone 130 by using the residual dissolved oxygen to obtain sewage C;
s30, enabling the sewage C to upwards enter the anoxic zone 140 through the first opening 113 at the bottom of the central cylinder 110, and carrying out anoxic denitrification in the anoxic zone 140 to obtain sewage D;
s40, enabling the sewage D to flow out of the central cylinder 110, enabling the sewage D to upwards enter the separation area 200 through the second opening 201, separating water from sludge in the separation area 200, discharging treated water supernatant through the water outlet 202 under the action of gravity sedimentation, and depositing the sludge at the bottom of the separation area 200 and discharging the sludge from the sludge outlet 203;
s50, feeding the sludge discharged from the sludge outlet 203 into the sludge activation zone 300 through the sludge inlet 303 through a pipeline, adding a carbon source into the sludge activation zone 300 through the medicine inlet 304, ensuring that the C/N/P of the mixed liquor is 100-500: 5:1, activating the sludge, and circularly feeding the treated activated sludge into the biological reaction zone 100 through the third opening 301, wherein the sludge reflux ratio is 50-100% so as to keep the sludge concentration in the biological reaction zone 100 at 4000-6000 mg/L.
Wherein, in the process of the sludge activation treatment in the step S50, a carbon source is added into the sludge activation zone through the medicine inlet, so that the sludge can be activated, and the problem of overhigh ammonia nitrogen and uneven nutrition in the wastewater can be solved.
After the high ammonia nitrogen wastewater treatment method of the embodiment is used for wastewater treatment, the COD (chemical oxygen demand) of the effluent is less than or equal to 50mg/L, the ammonia nitrogen is less than or equal to 5mg/L, and the total nitrogen is less than or equal to 10mg/L, compared with the prior art, the ammonia nitrogen removal rate of the high ammonia nitrogen wastewater is improved by 20-30% and the total nitrogen removal rate is improved by 25-30% within the same total retention time.
Example 2
The basic contents of this embodiment are the same as embodiment 1, except that: the volume ratio of the first aerobic zone 120 to the second aerobic zone 130 in the biological reaction zone 100 is 1.3:1.5, and the ratio of the lower cross section to the upper cross section of the top of the central cylinder is 1: 1.3.
The sewage A is obtained after the pretreatment of certain industrial wastewater, the water quality COD is 800-1000mg/L, the ammonia nitrogen is 100-120mg/L, the total nitrogen is 100-120mg/L, the biodegradability difference B/C of the wastewater is less than 0.3, and the specific treatment steps are as follows:
s10, enabling the sewage A to upwards enter a central cylinder 110 of the biological reaction zone 100 through a water distributor 112, starting an aeration device 111, controlling the oxygen content of the water body to be 2-3mg/L, and carrying out aerobic COD removal on the sewage A in a first aerobic zone 120 to obtain sewage B with most of COD removed;
s20, making the sewage B flow out of the central cylinder 110 and enter the second aerobic zone 130 downwards, and carrying out aerobic nitrification in the second aerobic zone 130 by using the residual dissolved oxygen to obtain sewage C;
s30, enabling the sewage C to upwards enter the anoxic zone 140 through the first opening 113 at the bottom of the central cylinder 110, and carrying out anoxic denitrification in the anoxic zone 140 to obtain sewage D;
s40, enabling the sewage D to flow out of the central cylinder 110, enabling the sewage D to upwards enter the separation area 200 through the second opening 201, separating water from sludge in the separation area 200, discharging treated water supernatant through the water outlet 202 under the action of gravity sedimentation, and depositing the sludge at the bottom of the separation area 200 and discharging the sludge from the sludge outlet 203;
s50, feeding the sludge discharged from the sludge outlet 203 into a sludge activation region 300 through a pipeline from a sludge inlet 303, and feeding a carbon source, a nitrobacteria agent and a coagulant into the sludge activation region 300 through a medicine inlet 304, wherein the feeding amount of the carbon source needs to ensure that the C/N/P of the mixed solution is 100-500: 5:1, the feeding amount of the nitrobacteria agent is 800-1200 mg/L, the feeding amount of the coagulant is one millionth of the sludge feeding amount of the sludge activation region, so that the sludge is activated, the treated activated sludge circularly enters a biological reaction region 100 through a third opening 301, the sludge reflux ratio is 80-150%, and the sludge concentration in the biological reaction region 100 is kept to be 3000-4000 mg/L.
Wherein, in the process of the sludge activation treatment in the step S50, a carbon source is added into the sludge activation zone through the medicine inlet to provide nutrition for the activated sludge, a nitrifying bacteria agent is added to enhance the sludge nitrification capacity, and a small amount of coagulant is added to enhance the sludge coagulation capacity.
After the high ammonia nitrogen wastewater treatment method of the embodiment is used for wastewater treatment, the COD (chemical oxygen demand) of the effluent is less than or equal to 300mg/L, the ammonia nitrogen is less than or equal to 5mg/L, and the total nitrogen is less than or equal to 10mg/L, compared with the prior art, the ammonia nitrogen removal rate of the high ammonia nitrogen wastewater is improved by 30-40% and the total nitrogen removal rate is improved by 25-30% within the same total retention time.
Example 3
The basic contents of this embodiment are the same as embodiment 1, except that: the volume ratio of the first aerobic zone 120 to the second aerobic zone 130 in the biological reaction zone 100 is 1.5:1.1, and the ratio of the lower cross section to the upper cross section of the top of the central cylinder is 1: 1.1.
The method comprises the following steps of pretreating certain pesticide wastewater to obtain sewage A, wherein the water quality COD is 800-1000mg/L, the ammonia nitrogen is 50-60mg/L, the total nitrogen is 80-100mg/L, the biodegradability of the wastewater is poorer than 0.3 and B/C is less than 0.4, and the specific treatment steps are as follows:
s10, enabling the sewage A to upwards enter a central cylinder 110 of the biological reaction zone 100 through a water distributor 112, starting an aeration device 111, controlling the oxygen content of the water body to be 2-3mg/L, and carrying out aerobic COD removal on the sewage A in a first aerobic zone 120 to obtain sewage B with most of COD removed;
s20, making the sewage B flow out of the central cylinder 110 and enter the second aerobic zone 130 downwards, and carrying out aerobic nitrification in the second aerobic zone 130 by using the residual dissolved oxygen to obtain sewage C;
s30, enabling the sewage C to upwards enter the anoxic zone 140 through the first opening 113 at the bottom of the central cylinder 110, and carrying out anoxic denitrification in the anoxic zone 140 to obtain sewage D;
s40, enabling the sewage D to flow out of the central cylinder 110, enabling the sewage D to upwards enter the separation area 200 through the second opening 201, separating water from sludge in the separation area 200, discharging treated water supernatant through the water outlet 202 under the action of gravity sedimentation, and depositing the sludge at the bottom of the separation area 200 and discharging the sludge from the sludge outlet 203;
s50, feeding the sludge discharged from the sludge outlet 203 into the sludge activation region 300 through the sludge inlet 303 through a pipeline, adding a carbon source and a coagulant into the sludge activation region 300 through the medicine inlet 304, wherein the carbon source adding amount needs to ensure that the C/N/P of the mixed solution is 100-500: 5:1, the coagulant adding amount is one millionth of the sludge inlet amount of the sludge activation region, activating the sludge, and circularly feeding the treated activated sludge into the biological reaction region 100 through the third opening 301, wherein the sludge reflux ratio is 80-120% so as to keep the sludge concentration in the biological reaction region at 4000-5000 mg/L.
Wherein, in the process of the sludge activation treatment in the step S50, a carbon source is added into the sludge activation area through the medicine inlet to provide nutrition for the activated sludge, and a small amount of coagulant is added to enhance the coagulation capacity of the sludge.
After the high ammonia nitrogen wastewater treatment method of the embodiment is used for wastewater treatment, the COD (chemical oxygen demand) of the effluent is less than or equal to 300mg/L, the ammonia nitrogen is less than or equal to 5mg/L, and the total nitrogen is less than or equal to 10mg/L, compared with the prior art, the ammonia nitrogen removal rate of the high ammonia nitrogen wastewater is improved by 30-40% and the total nitrogen removal rate is improved by 25-30% within the same total retention time.
The present invention and its embodiments have been described above schematically, the description is not restrictive, the data used are only one of the embodiments of the present invention, and the actual data combination is not limited to this. Therefore, if the person skilled in the art receives the teaching, the embodiments and examples similar to the above technical solutions shall not be designed in an inventive manner without departing from the spirit of the present invention, and shall fall within the protection scope of the present invention.
Claims (8)
1. The utility model provides a high ammonia-nitrogen concentration effluent treatment plant, includes biological reaction district (100) and disengagement zone (200), its characterized in that: the biological reaction zone (100) is provided with an air inlet (101) and a water inlet (102) at the top, a central cylinder (110) is arranged in the biological reaction zone (100), the cross section of the top of the central cylinder (110) is gradually increased from bottom to top, the ratio of the lower cross section to the upper cross section is 1: 1-1: 4, an aeration device (111) and a water distributor (112) are arranged in the central cylinder (110), the air inlet (101) is connected with the aeration device (111) through an air inlet pipeline, and the water inlet (102) is connected with the water distributor (112) through a water inlet pipeline;
a first aerobic zone (120) is formed between the top of the central cylinder (110) and the aeration device (111), a second aerobic zone (130) is formed between the top of the biological reaction zone (100) and the outside of the central cylinder (110), and the volume ratio of the first aerobic zone (120) to the second aerobic zone (130) is 2: 3-3: 2, a first opening (113) is arranged at the bottom of the central cylinder (110), and an anoxic zone (140) is formed between the first opening (113) and the aeration device (111);
a second opening (201) is arranged below the separation area (200), the separation area (200) is communicated with the biological reaction area (100) through the second opening (201), a water outlet (202) is arranged at the top of the separation area (200) and used for discharging treated water, and a sludge outlet (203) is arranged at the bottom of the separation area (200);
the high ammonia nitrogen wastewater treatment device further comprises a sludge activation zone (300), a third opening (301) is arranged above the sludge activation zone (300), the sludge activation zone (300) is communicated with the biological reaction zone (100), a flow impeller (302) is arranged at the third opening (301) and used for pushing activated sludge into the biological reaction zone (100) from the sludge activation zone (300), a sludge inlet (303) is arranged at the bottom of the sludge activation zone (300), and the sludge inlet (303) is connected with a sludge outlet (203) of the separation zone (200) through a pipeline.
2. The high ammonia nitrogen wastewater treatment device according to claim 1, characterized in that: the aeration device (111) and the water distributor (112) are positioned in the middle of the interior of the central barrel (110).
3. The high ammonia nitrogen wastewater treatment device according to claim 1, characterized in that: the sludge activation zone (300) comprises a first pore plate (310), a second pore plate (320) and a third pore plate (330), a first activation zone (311) is formed between the first pore plate (310) and the bottom of the sludge activation zone (300), a second activation zone (321) is formed between the first pore plate (310) and the second pore plate (320), a third activation zone (331) is formed between the second pore plate (320) and the third pore plate (330), a fourth activation zone (341) is formed between the third pore plate (330) and the top of the sludge activation zone (300), and a filler is filled in the second activation zone (321).
4. The high ammonia nitrogen wastewater treatment device according to claim 3, characterized in that: the pore diameter of the first pore plate (310) and the pore diameter of the third pore plate (330) are smaller than the particle diameter of the filler, and the pore diameter of the second pore plate (320) is larger than the particle diameter of the filler.
5. The high ammonia nitrogen wastewater treatment device according to claim 3, characterized in that: an air inlet device (332) is arranged in the third activation area (331).
6. The high ammonia nitrogen wastewater treatment device according to claim 4, characterized in that: the aperture of the first pore plate (310) is 20-30 mm, the aperture of the second pore plate (320) is 90-100 mm, the aperture of the third pore plate (330) is 20-30 mm, and the particle size of the filler is 50-60 mm.
7. A high ammonia nitrogen wastewater treatment method, which adopts the high ammonia nitrogen wastewater treatment device according to any one of claims 1-6 to treat wastewater, and comprises the following specific steps:
s10, enabling the sewage A to upwards enter a central cylinder (110) of a biological reaction zone (100) through a water distributor (112), starting an aeration device (111), and carrying out aerobic COD removal on the sewage A in a first aerobic zone (120) to obtain sewage B without COD;
s20, making the sewage B flow out of the central cylinder (110) and downwards enter a second aerobic zone (130), and carrying out aerobic nitrification in the second aerobic zone (130) to obtain sewage C;
s30, enabling the sewage C to upwards enter an anoxic zone (140) through a first opening (113) at the bottom of a central cylinder (110), and carrying out anoxic denitrification in the anoxic zone (140) to obtain sewage D;
s40, enabling the sewage D to flow out of the central cylinder (110), enabling the sewage D to upwards enter the separation area (200) through the second opening (201), separating sludge from a water body in the separation area (200), discharging the water body after separating the sludge through the water outlet (202), depositing the sludge at the bottom of the separation area (200) and discharging the sludge from the sludge outlet (203);
s50, enabling sludge discharged from the sludge outlet (203) to enter a sludge activation area (300) through a pipeline from a sludge inlet (303), adding a medicament into the sludge activation area (300) to activate the sludge, and enabling the activated sludge after treatment to circularly enter a biological reaction area (100) through a third opening (301).
8. The method for treating high ammonia nitrogen wastewater according to claim 7, which is characterized in that: the medicament is a carbon source or the combination of the carbon source and one or two of a biological agent or a coagulant.
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| CN114409077B (en) * | 2021-12-16 | 2022-12-23 | 南京环保产业创新中心有限公司 | Device and method for treating wastewater with low carbon-nitrogen ratio |
| CN116535005B (en) * | 2023-06-29 | 2023-09-01 | 成都理工大学 | Intelligent synchronous nitrification and denitrification treatment system and method for domestic sewage |
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