CN110818205A - System and process for reducing concentration of pollutants in steel comprehensive wastewater - Google Patents

System and process for reducing concentration of pollutants in steel comprehensive wastewater Download PDF

Info

Publication number
CN110818205A
CN110818205A CN201911221029.1A CN201911221029A CN110818205A CN 110818205 A CN110818205 A CN 110818205A CN 201911221029 A CN201911221029 A CN 201911221029A CN 110818205 A CN110818205 A CN 110818205A
Authority
CN
China
Prior art keywords
wastewater
tank
water
filter
sludge
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
CN201911221029.1A
Other languages
Chinese (zh)
Inventor
冯占立
于丰浩
杨冶
张新宇
王远志
王军强
杨志超
刁振东
王丹锫
刘佳诚
范丽丽
程诺嘉
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.)
Ansteel Engineering Technology Corp Ltd
Original Assignee
Ansteel Engineering Technology Corp Ltd
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 Ansteel Engineering Technology Corp Ltd filed Critical Ansteel Engineering Technology Corp Ltd
Priority to CN201911221029.1A priority Critical patent/CN110818205A/en
Publication of CN110818205A publication Critical patent/CN110818205A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00Multistage treatment of water, waste water or sewage
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/24Treatment of water, waste water, or sewage by flotation
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/52Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/5236Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
    • C02F1/5245Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/52Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • C02F1/54Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using organic material
    • C02F1/56Macromolecular compounds
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/72Treatment of water, waste water, or sewage by oxidation
    • C02F1/725Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/72Treatment of water, waste water, or sewage by oxidation
    • C02F1/727Treatment of water, waste water, or sewage by oxidation using pure oxygen or oxygen rich gas
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/72Treatment of water, waste water, or sewage by oxidation
    • C02F1/78Treatment of water, waste water, or sewage by oxidation with ozone
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F2001/007Processes including a sedimentation step
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00Nature of the contaminant
    • C02F2101/10Inorganic compounds
    • C02F2101/12Halogens or halogen-containing compounds
    • C02F2101/14Fluorine or fluorine-containing compounds
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00Nature of the contaminant
    • C02F2101/10Inorganic compounds
    • C02F2101/16Nitrogen compounds, e.g. ammonia
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00Nature of the contaminant
    • C02F2101/10Inorganic compounds
    • C02F2101/20Heavy metals or heavy metal compounds
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/16Nature of the water, waste water, sewage or sludge to be treated from metallurgical processes, i.e. from the production, refining or treatment of metals, e.g. galvanic wastes
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00Biological treatment of water, waste water, or sewage
    • C02F3/30Aerobic and anaerobic processes
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00Biological treatment of water, waste water, or sewage
    • C02F3/34Biological treatment of water, waste water, or sewage characterised by the microorganisms used

Abstract

The invention relates to a system and a process for reducing the concentration of pollutants in steel and iron comprehensive wastewater, wherein the system comprises a regulating tank, a high-density sedimentation tank, a biological aerated filter, a denitrification biological filter, a high-efficiency dissolved air flotation tank, a filter and an ozone catalytic oxidation tank which are sequentially connected through a wastewater pipeline; the invention can thoroughly convert pollutants in the wastewater into non-pollutants, achieves the aim of reducing the concentration of the pollutants, meets the requirements on the special discharge limit of the water pollutants in Table 3 of the discharge standard GB13456-2012 of the pollutants for the water in the iron and steel industry, and completely meets the water quality index of the inlet water for the desalting and recycling by the double-membrane method, thereby prolonging the service life of the desalting and recycling facility.

Description

System and process for reducing concentration of pollutants in steel comprehensive wastewater
Technical Field
The invention relates to the technical field of industrial wastewater treatment, in particular to a system and a process for reducing the concentration of pollutants in steel comprehensive wastewater.
Background
Steel enterprises are large water consumers, and produce large-scale production wastewater, and indexes such as SS, COD, ammonia nitrogen, total nitrogen, fluoride, cyanide and the like in the wastewater are easy to exceed standards and cannot be directly discharged. The industrial wastewater is desalted and recycled, but the method does not remove the pollutants, but transfers the pollutants into the strong brine, and the strong brine is reused to cause secondary pollution. In addition, the double-membrane desalination has strict requirements on inlet water, the inlet water quality is good, and the service life of the desalination equipment can be greatly prolonged. Therefore, it is preferable to reduce the concentration of the pollutants before the wastewater enters the double-membrane desalination system.
Disclosure of Invention
The invention provides a system and a process for reducing the concentration of pollutants in comprehensive steel wastewater, which can thoroughly convert pollutants in the wastewater into non-pollutants, achieve the purpose of reducing the concentration of the pollutants, meet the requirements of special discharge limit values of water pollutants in Table 3 of the discharge standard GB13456-2012 of pollutants for water in the steel industry, and completely meet the water quality index of inlet water for desalting and recycling by a double-membrane method, so as to prolong the service life of desalting and recycling facilities.
In order to achieve the purpose, the invention adopts the following technical scheme:
a system for reducing the concentration of pollutants in steel and iron comprehensive wastewater comprises a regulating tank, a high-density sedimentation tank, an aeration biological filter, a denitrification biological filter, a high-efficiency dissolved air flotation tank, a filter and an ozone catalytic oxidation tank which are sequentially connected through a wastewater pipeline; wherein:
a liftable aerator is arranged in the regulating tank;
the high-density sedimentation tank is provided with a drug feeding device and a sediment discharge port which is connected with a sludge treatment system through a pipeline;
a fixed aerator is arranged in the biological aerated filter and is connected with an air suspension fan through a pipeline;
the denitrification biological filter is provided with an inert gas inlet and a carbon source adding device; the bottom of the denitrification biological filter is provided with a water inlet, the upper part of the denitrification biological filter is provided with a water outlet, and the filter body is internally provided with at least 2 filter layers which comprise an aerobic bacteria inhibition layer arranged on the lower layer and a denitrification layer arranged on the upper layer;
a pipe reactor is arranged on a wastewater pipeline at the upstream of the high-efficiency dissolved air floatation tank, and the pipe reactor is provided with a phosphorus removing agent adding port and a flocculating agent adding port; the high-efficiency dissolved air flotation tank is sequentially divided into a water inlet area, a water distribution area and a separation area along the water flow direction, the water inlet of the water inlet area is connected with the water outlet of the tubular reactor, and the water inlet area is provided with an air flotation device; the top of the water distribution area is provided with a slag scraper, the lower part of the water distribution area is provided with a corrugated inclined plate, and the bottom of the water distribution area is provided with a sludge discharge port; the bottom of the separation area is provided with a mud scraper and an automatic mud valve; the residue scraper is connected with the sludge treatment system through a residue discharge groove, the sludge scraper is connected with the sludge treatment system through a sludge discharge pipeline, and an automatic sludge discharge valve is arranged on the sludge discharge pipeline.
And a heating device is also arranged in the regulating tank, and the heating device is an electric heating device or a steam heating device.
The medicine adding device in the high-density sedimentation tank is one or more of a lime adding device, a calcium chloride adding device, a sodium carbonate adding device, a sodium bicarbonate adding device, a PAC adding device and a PAM adding device.
The air suspension fan is controlled by adopting frequency conversion.
The air supporting device is composed of a dissolved air tank, a circulating pump and a releaser, an air inlet, a circulating water inlet and a dissolved air water outlet are arranged on the dissolved air tank, the circulating water inlet is connected with a circulating water outlet in a water inlet area through a circulating water pipeline, the circulating pump is arranged on the circulating water pipeline, and the dissolved air water outlet is connected with the releaser in the water inlet area.
The filter is a sand filter or a V-shaped filter.
A back washing water outlet is arranged on a waste water pipeline at the downstream of the filter pool, and the back washing water outlet is respectively connected with the biological aerated filter, the biological denitrification filter and a back washing water inlet of the filter pool through back washing water pipelines; the aeration biological filter, the denitrification biological filter and the filter are respectively provided with a backwashing water outlet and are connected with the regulating tank through a backwashing water drainage pipeline.
A process for reducing the concentration of pollutants in steel comprehensive wastewater comprises the following steps:
1) the method comprises the following steps that (1) steel comprehensive wastewater firstly enters an adjusting tank, and the adjusting tank is used for adjusting water quantity, balancing water quality and preventing sludge from precipitating; the waste water is oxygenated by aeration, and the ferrous iron in the waste water is oxidized into ferric iron so as to remove the total iron by adding lime into a subsequent high-density sedimentation tank to form ferric hydroxide sediment, thereby meeting the requirements of desalting and recycling the waste water; heating the wastewater in the adjusting tank according to the requirement, and avoiding the influence on the subsequent biochemical treatment effect and the double-membrane desalination water yield due to the over-low water temperature;
2) the effluent of the regulating tank enters a high-density sedimentation tank; in the high-density sedimentation tank, medicaments are added according to the water quality condition of the wastewater, and the method comprises the steps of adding lime to remove hardness so as to meet the requirements of desalting and recycling the wastewater; lime and calcium chloride are added to remove fluoride, so that the standard reaching requirement of the fluoride in the effluent is met; adding sodium carbonate or sodium bicarbonate to supplement alkalinity so as to meet the alkalinity required by ammoniation reaction and the alkalinity requirement in the subsequent ammonia nitrogen removal; PAC and PAM are added to form floc so as to remove SS; sludge generated by the high-density sedimentation tank enters a sludge treatment system for treatment;
3) the effluent of the high-density sedimentation tank enters an aeration biological filter; removing COD in the wastewater in the biological aerated filter, and converting ammonia nitrogen into nitrate;
4) the effluent of the aeration biological filter enters a denitrification biological filter; the denitrification biological filter adopts an upward water outlet mode, wastewater firstly passes through the aerobic bacteria inhibition layer to reduce DO, and then passes through the denitrification layer; when the wastewater passes through the denitrification layer, an external carbon source is taken as an electron donor to perform denitrification reaction, so that nitrate is converted into nitrogen to be discharged; adding inert gas to expand the filter material, and allowing aged sludge generated by organisms to flow out along water flow;
5) the effluent of the denitrification biological filter enters a high-efficiency dissolved air flotation tank; the wastewater firstly enters a tubular reactor, and a phosphorus removing agent and a flocculating agent are added into the tubular reactor to enable impurities in the wastewater to form separable flocculates; after the wastewater enters the water inlet area, the flocculate is contacted with bubbles with the diameter of 30-50 um released in the dissolved air to form a low-density 'air floating body', oil and suspended matters in the wastewater are removed at the same time, the flocculate is coalesced into scum in the water distribution area, and the scum is scraped to a scum collecting tank through a scum scraper and then automatically flows and is discharged into a sludge treatment system; the flocs with lower ascending speed and water flow downwards to be further coalesced through the corrugated inclined plate, the flocs with low density float to the water surface, the flocs with high density precipitate to the bottom, and sand deposited in the water distribution area is discharged through a sand discharge port; the silt precipitated in the water inlet area and the sludge precipitated at the bottom of the separation area are scraped to a sludge discharge end by a sludge scraper and are periodically and quantitatively discharged into a sludge treatment system through an automatic sludge discharge valve;
6) the water discharged from the high-efficiency dissolved air floatation tank enters a filter tank to remove suspended matters and reduce turbidity;
7) the effluent of the filter tank enters an ozone catalytic oxidation tank, part of COD in the wastewater is degraded in a high-density sedimentation tank and an aeration biofiltration tank, and the rest part of the COD is removed in the ozone catalytic oxidation tank; the COD and BOD in the wastewater can be ensured to reach the standard through the ozone catalytic oxidation tank, and the COD of the effluent of the system is less than or equal to 30 mg/L.
As a pretreatment process of the double-membrane desalting process, the effluent of the system enters a double-membrane desalting system, and the step 5) is omitted or the effluent of the denitrification biological filter is directly sent to a subsequent treatment device through an overtaking pipeline.
Compared with the prior art, the invention has the beneficial effects that:
1) the process and the system are reasonable in arrangement, can adapt to the quality of the steel comprehensive wastewater, and can simultaneously remove SS, COD, ammonia nitrogen, total nitrogen, fluoride, hardness, turbidity, chromaticity, total iron, oil and other pollutants in the wastewater.
2) The treated wastewater can meet the requirements of special emission limit index indexes of water pollutants in Table 3 of the discharge standard GB13456-2012 of pollutants for water in the iron and steel industry, and can be used as a pretreatment process for desalting by a double-membrane method;
3) the removal rate of pollutants in the wastewater is greatly improved, the removal rate of ammonia nitrogen can reach more than 95%, the removal rate of COD can reach more than 90%, and the removal rate of total nitrogen can reach more than 90%.
Drawings
FIG. 1 is a schematic structural diagram of a system for reducing the pollutant concentration in integrated steel wastewater according to the present invention.
Detailed Description
The following further describes embodiments of the present invention with reference to the accompanying drawings:
as shown in figure 1, the system for reducing the concentration of pollutants in the comprehensive wastewater of steel comprises a regulating tank, a high-density sedimentation tank, a biological aerated filter, a biological denitrification filter, a high-efficiency dissolved air flotation tank, a filter and an ozone catalytic oxidation tank which are sequentially connected through a wastewater pipeline; wherein:
a liftable aerator is arranged in the regulating tank;
the high-density sedimentation tank is provided with a drug feeding device and a sediment discharge port which is connected with a sludge treatment system through a pipeline;
a fixed aerator is arranged in the biological aerated filter and is connected with an air suspension fan through a pipeline;
the denitrification biological filter is provided with an inert gas inlet and a carbon source adding device; the bottom of the denitrification biological filter is provided with a water inlet, the upper part of the denitrification biological filter is provided with a water outlet, and the filter body is internally provided with at least 2 filter layers which comprise an aerobic bacteria inhibition layer arranged on the lower layer and a denitrification layer arranged on the upper layer;
a pipe reactor is arranged on a wastewater pipeline at the upstream of the high-efficiency dissolved air floatation tank, and the pipe reactor is provided with a phosphorus removing agent adding port and a flocculating agent adding port; the high-efficiency dissolved air flotation tank is sequentially divided into a water inlet area, a water distribution area and a separation area along the water flow direction, the water inlet of the water inlet area is connected with the water outlet of the tubular reactor, and the water inlet area is provided with an air flotation device; the top of the water distribution area is provided with a slag scraper, the lower part of the water distribution area is provided with a corrugated inclined plate, and the bottom of the water distribution area is provided with a sludge discharge port; the bottom of the separation area is provided with a mud scraper and an automatic mud valve; the residue scraper is connected with the sludge treatment system through a residue discharge groove, the sludge scraper is connected with the sludge treatment system through a sludge discharge pipeline, and an automatic sludge discharge valve is arranged on the sludge discharge pipeline.
And a heating device is also arranged in the regulating tank, and the heating device is an electric heating device or a steam heating device.
The medicine adding device in the high-density sedimentation tank is one or more of a lime adding device, a calcium chloride adding device, a sodium carbonate adding device, a sodium bicarbonate adding device, a PAC adding device and a PAM adding device.
The air suspension fan is controlled by adopting frequency conversion.
The air supporting device is composed of a dissolved air tank, a circulating pump and a releaser, an air inlet, a circulating water inlet and a dissolved air water outlet are arranged on the dissolved air tank, the circulating water inlet is connected with a circulating water outlet in a water inlet area through a circulating water pipeline, the circulating pump is arranged on the circulating water pipeline, and the dissolved air water outlet is connected with the releaser in the water inlet area.
The filter is a sand filter or a V-shaped filter.
A back washing water outlet is arranged on a waste water pipeline at the downstream of the filter pool, and the back washing water outlet is respectively connected with the biological aerated filter, the biological denitrification filter and a back washing water inlet of the filter pool through back washing water pipelines; the aeration biological filter, the denitrification biological filter and the filter are respectively provided with a backwashing water outlet and are connected with the regulating tank through a backwashing water drainage pipeline.
A process for reducing the concentration of pollutants in steel comprehensive wastewater comprises the following steps:
1) the method comprises the following steps that (1) steel comprehensive wastewater firstly enters an adjusting tank, and the adjusting tank is used for adjusting water quantity, balancing water quality and preventing sludge from precipitating; the waste water is oxygenated by aeration, and the ferrous iron in the waste water is oxidized into ferric iron so as to remove the total iron by adding lime into a subsequent high-density sedimentation tank to form ferric hydroxide sediment, thereby meeting the requirements of desalting and recycling the waste water; heating the wastewater in the adjusting tank according to the requirement, and avoiding the influence on the subsequent biochemical treatment effect and the double-membrane desalination water yield due to the over-low water temperature;
2) the effluent of the regulating tank enters a high-density sedimentation tank; in the high-density sedimentation tank, medicaments are added according to the water quality condition of the wastewater, and the method comprises the steps of adding lime to remove hardness so as to meet the requirements of desalting and recycling the wastewater; lime and calcium chloride are added to remove fluoride, so that the standard reaching requirement of the fluoride in the effluent is met; adding sodium carbonate or sodium bicarbonate to supplement alkalinity so as to meet the alkalinity required by ammoniation reaction and the alkalinity requirement in the subsequent ammonia nitrogen removal; PAC and PAM are added to form floc so as to remove SS; sludge generated by the high-density sedimentation tank enters a sludge treatment system for treatment;
3) the effluent of the high-density sedimentation tank enters an aeration biological filter; removing COD in the wastewater in the biological aerated filter, and converting ammonia nitrogen into nitrate;
4) the effluent of the aeration biological filter enters a denitrification biological filter; the denitrification biological filter adopts an upward water outlet mode, wastewater firstly passes through the aerobic bacteria inhibition layer to reduce DO, and then passes through the denitrification layer; when the wastewater passes through the denitrification layer, an external carbon source is taken as an electron donor to perform denitrification reaction, so that nitrate is converted into nitrogen to be discharged; adding inert gas to expand the filter material, and allowing aged sludge generated by organisms to flow out along water flow;
5) the effluent of the denitrification biological filter enters a high-efficiency dissolved air flotation tank; the wastewater firstly enters a tubular reactor, and a phosphorus removing agent and a flocculating agent are added into the tubular reactor to enable impurities in the wastewater to form separable flocculates; after the wastewater enters the water inlet area, the flocculate is contacted with bubbles with the diameter of 30-50 um released in the dissolved air to form a low-density 'air floating body', oil and suspended matters in the wastewater are removed at the same time, the flocculate is coalesced into scum in the water distribution area, and the scum is scraped to a scum collecting tank through a scum scraper and then automatically flows and is discharged into a sludge treatment system; the flocs with lower ascending speed and water flow downwards to be further coalesced through the corrugated inclined plate, the flocs with low density float to the water surface, the flocs with high density precipitate to the bottom, and sand deposited in the water distribution area is discharged through a sand discharge port; the silt precipitated in the water inlet area and the sludge precipitated at the bottom of the separation area are scraped to a sludge discharge end by a sludge scraper and are periodically and quantitatively discharged into a sludge treatment system through an automatic sludge discharge valve;
6) the water discharged from the high-efficiency dissolved air floatation tank enters a filter tank to remove suspended matters and reduce turbidity;
7) the effluent of the filter tank enters an ozone catalytic oxidation tank, part of COD in the wastewater is degraded in a high-density sedimentation tank and an aeration biofiltration tank, and the rest part of the COD is removed in the ozone catalytic oxidation tank; the COD and BOD in the wastewater can be ensured to reach the standard through the ozone catalytic oxidation tank, and the COD of the effluent of the system is less than or equal to 30 mg/L.
As a pretreatment process of the double-membrane desalting process, the effluent of the system enters a double-membrane desalting system, and the step 5) is omitted or the effluent of the denitrification biological filter is directly sent to a subsequent treatment device through an overtaking pipeline.
The biological aerated filter adopts an air suspension fan for aeration, and performs frequency conversion control according to the DO condition of the effluent, thereby saving the power consumption.
The denitrification biological filter uses inert gas to expel DO, so that the denitrification effect is improved; and (3) carrying out denitrification reaction by adopting an external carbon source. The filter material for inhibiting the growth of bacteria is arranged at the lower layer, the added carbon source is not consumed due to the growth of aerobic bacteria, and the carbon source is saved by about one third. And (3) adopting an upper water outlet mode, wherein the wastewater passes through a denitrification layer, an external carbon source is taken as an electron donor to perform denitrification reaction, and nitrate is converted into nitrogen to be discharged. Meanwhile, due to the entry of inert gas, the filter material expands, aged sludge generated by organisms flows out along with water flow, the blocking probability of the filter material is reduced, and the backwashing period is prolonged. If the effluent of the system enters the double-membrane desalination system, the denitrification biological filter tank process can be eliminated or the overtaking setting can be carried out through an overtaking pipeline.
The high-efficiency dissolved air flotation tank is used for removing biological sludge which is generated in the denitrification process and is difficult to settle, and reducing the subsequent filtering pressure; remove the oil in the waste water, protect the follow-up two membrane method desalination systems, prevent that oil from making the dirt of membrane and blocking. Because the biological sludge contains air bubbles and is difficult to precipitate, the incoming water firstly enters the tubular reactor, the flocculating agent is added into the tubular reactor to form separable flocs, and the separable flocs are coalesced and compacted after being mixed with partial dissolved air water. Sediment precipitated in the water inlet area and sludge precipitated at the bottom of the separation area are scraped to a sludge discharge end by a sludge scraper and are discharged into a sludge system regularly and quantitatively through an automatic sludge discharge valve, so that the normal operation of the equipment is not influenced.
The air floating device adopts air as an air source, and is mixed with the water pressurized by the circulating pump in the dissolved air tank to form dissolved air water which is released to the water inlet chamber through the releaser. Can simultaneously remove oil and suspended matters in the wastewater, protect the quality of the subsequent desalting influent water by a double-membrane method and prolong the backwashing period of the filter tank.
The ozone catalytic oxidation pond plays a role in reducing COD (chemical oxygen demand) and chromaticity of effluent. Part of COD in the wastewater is degraded in a high-density sedimentation tank and a biological aerated filter, and the rest part of COD is removed in an ozone catalytic oxidation tank; in order to achieve higher removal effect of denitrification and prevent excessive or incomplete utilization of added carbon source by organisms, the ozone catalytic oxidation tank can play a role in ensuring that COD and BOD of effluent do not exceed the standard.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims (9)

1. A system for reducing the concentration of pollutants in steel and iron comprehensive wastewater is characterized by comprising a regulating tank, a high-density sedimentation tank, a biological aerated filter, a denitrification biological filter, a high-efficiency dissolved air floatation tank, a filter and an ozone catalytic oxidation tank which are sequentially connected through a wastewater pipeline; wherein:
a liftable aerator is arranged in the regulating tank;
the high-density sedimentation tank is provided with a drug feeding device and a sediment discharge port which is connected with a sludge treatment system through a pipeline;
a fixed aerator is arranged in the biological aerated filter and is connected with an air suspension fan through a pipeline;
the denitrification biological filter is provided with an inert gas inlet and a carbon source adding device; the bottom of the denitrification biological filter is provided with a water inlet, the upper part of the denitrification biological filter is provided with a water outlet, and the filter body is internally provided with at least 2 filter layers which comprise an aerobic bacteria inhibition layer arranged on the lower layer and a denitrification layer arranged on the upper layer;
a pipe reactor is arranged on a wastewater pipeline at the upstream of the high-efficiency dissolved air floatation tank, and the pipe reactor is provided with a phosphorus removing agent adding port and a flocculating agent adding port; the high-efficiency dissolved air flotation tank is sequentially divided into a water inlet area, a water distribution area and a separation area along the water flow direction, the water inlet of the water inlet area is connected with the water outlet of the tubular reactor, and the water inlet area is provided with an air flotation device; the top of the water distribution area is provided with a slag scraper, the lower part of the water distribution area is provided with a corrugated inclined plate, and the bottom of the water distribution area is provided with a sludge discharge port; the bottom of the separation area is provided with a mud scraper and an automatic mud valve; the residue scraper is connected with the sludge treatment system through a residue discharge groove, the sludge scraper is connected with the sludge treatment system through a sludge discharge pipeline, and an automatic sludge discharge valve is arranged on the sludge discharge pipeline.
2. The system for reducing the pollutant concentration in the integrated steel and iron wastewater according to claim 1, characterized in that a heating device is further arranged in the regulating tank, and the heating device is an electric heating device or a steam heating device.
3. The system for reducing the concentration of pollutants in comprehensive wastewater of iron and steel according to claim 1, wherein the drug adding device in the high-density sedimentation tank is one or more of a lime adding device, a calcium chloride adding device, a sodium carbonate adding device, a sodium bicarbonate adding device, a PAC adding device and a PAM adding device.
4. The system for reducing the concentration of pollutants in integrated steel and iron wastewater according to claim 1, wherein the air suspension fan is controlled by frequency conversion.
5. The system for reducing the concentration of pollutants in wastewater from iron and steel synthesis as claimed in claim 1, wherein the air flotation device comprises a dissolved air tank, a circulating pump and a releaser, the dissolved air tank is provided with an air inlet, a circulating water inlet and a dissolved air water outlet, the circulating water inlet is connected with the circulating water outlet on the water inlet area through a circulating water pipeline, the circulating water pipeline is provided with a circulating pump, and the dissolved air water outlet is connected with the releaser in the water inlet area.
6. The system for reducing the pollutant concentration in integrated steel and iron wastewater according to claim 1, characterized in that the filter is a sand filter or a V-shaped filter.
7. The system for reducing the concentration of pollutants in wastewater from integrated steel and iron production according to claim 1, wherein a back-washing water outlet is arranged on a wastewater pipeline at the downstream of the filter tank, and the back-washing water outlet is respectively connected with the biological aerated filter, the biological denitrification filter and a back-washing water inlet of the filter tank through back-washing water pipelines; the aeration biological filter, the denitrification biological filter and the filter are respectively provided with a backwashing water outlet and are connected with the regulating tank through a backwashing water drainage pipeline.
8. A process for reducing the concentration of pollutants in integrated steel and iron wastewater based on the system of claim 1, comprising the steps of:
1) the method comprises the following steps that (1) steel comprehensive wastewater firstly enters an adjusting tank, and the adjusting tank is used for adjusting water quantity, balancing water quality and preventing sludge from precipitating; the waste water is oxygenated by aeration, and the ferrous iron in the waste water is oxidized into ferric iron so as to remove the total iron by adding lime into a subsequent high-density sedimentation tank to form ferric hydroxide sediment, thereby meeting the requirements of desalting and recycling the waste water; heating the wastewater in the adjusting tank according to the requirement, and avoiding the influence on the subsequent biochemical treatment effect and the double-membrane desalination water yield due to the over-low water temperature;
2) the effluent of the regulating tank enters a high-density sedimentation tank; in the high-density sedimentation tank, medicaments are added according to the water quality condition of the wastewater, and the method comprises the steps of adding lime to remove hardness so as to meet the requirements of desalting and recycling the wastewater; lime and calcium chloride are added to remove fluoride, so that the standard reaching requirement of the fluoride in the effluent is met; adding sodium carbonate or sodium bicarbonate to supplement alkalinity so as to meet the alkalinity required by ammoniation reaction and the alkalinity requirement in the subsequent ammonia nitrogen removal; PAC and PAM are added to form floc so as to remove SS; sludge generated by the high-density sedimentation tank enters a sludge treatment system for treatment;
3) the effluent of the high-density sedimentation tank enters an aeration biological filter; removing COD in the wastewater in the biological aerated filter, and converting ammonia nitrogen into nitrate;
4) the effluent of the aeration biological filter enters a denitrification biological filter; the denitrification biological filter adopts an upward water outlet mode, wastewater firstly passes through the aerobic bacteria inhibition layer to reduce DO, and then passes through the denitrification layer; when the wastewater passes through the denitrification layer, an external carbon source is taken as an electron donor to perform denitrification reaction, so that nitrate is converted into nitrogen to be discharged; adding inert gas to expand the filter material, and allowing aged sludge generated by organisms to flow out along water flow;
5) the effluent of the denitrification biological filter enters a high-efficiency dissolved air flotation tank; the wastewater firstly enters a tubular reactor, and a phosphorus removing agent and a flocculating agent are added into the tubular reactor to enable impurities in the wastewater to form separable flocculates; after the wastewater enters the water inlet area, the flocculate is contacted with bubbles with the diameter of 30-50 um released in the dissolved air to form a low-density 'air floating body', oil and suspended matters in the wastewater are removed at the same time, the flocculate is coalesced into scum in the water distribution area, and the scum is scraped to a scum collecting tank through a scum scraper and then automatically flows and is discharged into a sludge treatment system; the flocs with lower ascending speed and water flow downwards to be further coalesced through the corrugated inclined plate, the flocs with low density float to the water surface, the flocs with high density precipitate to the bottom, and sand deposited in the water distribution area is discharged through a sand discharge port; the silt precipitated in the water inlet area and the sludge precipitated at the bottom of the separation area are scraped to a sludge discharge end by a sludge scraper and are periodically and quantitatively discharged into a sludge treatment system through an automatic sludge discharge valve;
6) the water discharged from the high-efficiency dissolved air floatation tank enters a filter tank to remove suspended matters and reduce turbidity;
7) the effluent of the filter tank enters an ozone catalytic oxidation tank, part of COD in the wastewater is degraded in a high-density sedimentation tank and an aeration biofiltration tank, and the rest part of the COD is removed in the ozone catalytic oxidation tank; the COD and BOD in the wastewater can be ensured to reach the standard through the ozone catalytic oxidation tank, and the COD of the effluent of the system is less than or equal to 30 mg/L.
9. The process for reducing the pollutant concentration in the integrated wastewater of iron and steel according to claim 8, wherein as a pretreatment process of the double-membrane desalination process, the effluent of the system enters a double-membrane desalination system, and the step 5) is omitted or the effluent of the denitrification biofilter is directly sent to a subsequent treatment device through an overtaking pipeline.
CN201911221029.1A 2019-12-03 2019-12-03 System and process for reducing concentration of pollutants in steel comprehensive wastewater Pending CN110818205A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911221029.1A CN110818205A (en) 2019-12-03 2019-12-03 System and process for reducing concentration of pollutants in steel comprehensive wastewater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911221029.1A CN110818205A (en) 2019-12-03 2019-12-03 System and process for reducing concentration of pollutants in steel comprehensive wastewater

Publications (1)

Publication Number Publication Date
CN110818205A true CN110818205A (en) 2020-02-21

Family

ID=69543507

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911221029.1A Pending CN110818205A (en) 2019-12-03 2019-12-03 System and process for reducing concentration of pollutants in steel comprehensive wastewater

Country Status (1)

Country Link
CN (1) CN110818205A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111233285A (en) * 2020-03-25 2020-06-05 安徽中源锦天环境科技股份有限公司 Integrated sewage purification and upgrading process
CN113968606A (en) * 2021-06-25 2022-01-25 北京绿恒科技有限公司 Self-circulation high-density suspended sludge filtering and settling tank and water treatment system
CN114804395A (en) * 2021-01-21 2022-07-29 上海城投污水处理有限公司 Backwashing wastewater treatment device and treatment process for denitrification deep bed filter
CN114956298A (en) * 2022-06-20 2022-08-30 哈尔滨泽能环保科技有限公司 Dissolved air catalytic system for municipal sewage and application thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201971694U (en) * 2011-04-06 2011-09-14 中冶赛迪工程技术股份有限公司 Flotation-sedimentation tank with sideward flow inclined plate
MX2011010713A (en) * 2011-10-11 2012-01-27 Sadot Bermejo Lajud Process for treating congenital water.
CN103936093A (en) * 2014-05-12 2014-07-23 辽宁华霆环保科技有限公司 High-efficiency dissolved air flotation system
CN106698861A (en) * 2017-03-07 2017-05-24 鞍钢集团工程技术有限公司 Oversize steel enterprise comprehensive wastewater advanced treatment recycling technique and system
CN206799741U (en) * 2017-05-31 2017-12-26 海盐建盛五金制品有限公司 A kind of metal wire rod pretreating device
CN110204044A (en) * 2019-06-24 2019-09-06 鞍钢集团工程技术有限公司 A kind of method and device of intensified anti-nitrated removing total nitrogen
CN211521950U (en) * 2019-12-03 2020-09-18 鞍钢集团工程技术有限公司 System for reducing concentration of pollutants in steel comprehensive wastewater

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201971694U (en) * 2011-04-06 2011-09-14 中冶赛迪工程技术股份有限公司 Flotation-sedimentation tank with sideward flow inclined plate
MX2011010713A (en) * 2011-10-11 2012-01-27 Sadot Bermejo Lajud Process for treating congenital water.
CN103936093A (en) * 2014-05-12 2014-07-23 辽宁华霆环保科技有限公司 High-efficiency dissolved air flotation system
CN106698861A (en) * 2017-03-07 2017-05-24 鞍钢集团工程技术有限公司 Oversize steel enterprise comprehensive wastewater advanced treatment recycling technique and system
CN206799741U (en) * 2017-05-31 2017-12-26 海盐建盛五金制品有限公司 A kind of metal wire rod pretreating device
CN110204044A (en) * 2019-06-24 2019-09-06 鞍钢集团工程技术有限公司 A kind of method and device of intensified anti-nitrated removing total nitrogen
CN211521950U (en) * 2019-12-03 2020-09-18 鞍钢集团工程技术有限公司 System for reducing concentration of pollutants in steel comprehensive wastewater

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
曾郴林等: "《工业废水处理工程设计实例》", 国防工业出版社, pages: 702 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111233285A (en) * 2020-03-25 2020-06-05 安徽中源锦天环境科技股份有限公司 Integrated sewage purification and upgrading process
CN114804395A (en) * 2021-01-21 2022-07-29 上海城投污水处理有限公司 Backwashing wastewater treatment device and treatment process for denitrification deep bed filter
CN113968606A (en) * 2021-06-25 2022-01-25 北京绿恒科技有限公司 Self-circulation high-density suspended sludge filtering and settling tank and water treatment system
CN114956298A (en) * 2022-06-20 2022-08-30 哈尔滨泽能环保科技有限公司 Dissolved air catalytic system for municipal sewage and application thereof

Similar Documents

Publication Publication Date Title
CN110818205A (en) System and process for reducing concentration of pollutants in steel comprehensive wastewater
CN103288309A (en) Coal gasification wastewater zero-emission treatment method, treatment system and application thereof
CN108101316B (en) Asphalt production wastewater treatment process
CN105565581B (en) Coal ethylene wastewater integrated conduct method
CN107986551B (en) Method for treating leachate of garbage transfer station
Adachi et al. Reclamation and reuse of wastewater by biological aerated filter process
CN111453920A (en) Anodic oxidation wastewater treatment method and system
CN201746432U (en) Apparatus for strengthening treatment of coking waste water
CN114940561A (en) Oil sludge treatment waste liquid treatment system
CN107973488B (en) Method for denitrification treatment of ammonia nitrogen wastewater
CN211521950U (en) System for reducing concentration of pollutants in steel comprehensive wastewater
CN210885705U (en) Reclaimed water recycling system for petrochemical wastewater
CN106430846A (en) Efficient treatment integrated process for recalcitrant wastewater with low organic matter content
CN113277677B (en) Treatment method and reuse water treatment process for production wastewater of disposable nitrile gloves
CN110563232A (en) Mineral recovery and zero discharge process for high-salinity high-organic-matter wastewater
CN110713318B (en) Treatment system and treatment method for dehydration filtrate after anaerobic digestion of sludge
CN210457829U (en) Landfill leachate's treatment facility
CN210030310U (en) Treatment and recycling device for coking wastewater
CN210340626U (en) Blue algae deep dehydration wastewater treatment system
CN110183066B (en) Blue algae deep dehydration wastewater treatment system and process
KR20010045253A (en) Advanced method for treating wastewater and apparatus therefor
CN111392984A (en) Advanced treatment system and method for supplementing water by using urban reclaimed water as circulating water of power plant
CN206143022U (en) Bamboo article processing effluent disposal system
CN219709306U (en) Simultaneously is applicable to hot electrogalvanizing cold rolling acid-base wastewater treatment and recycling system
CN212102493U (en) Advanced treatment system for supplementing water by using urban reclaimed water as circulating water of power plant

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