CN117326688A - Method for directionally regulating and controlling sulfur-based filler autotrophic denitrification filter - Google Patents
Method for directionally regulating and controlling sulfur-based filler autotrophic denitrification filter Download PDFInfo
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- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 66
- 239000011593 sulfur Substances 0.000 title claims abstract description 59
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 59
- 238000000034 method Methods 0.000 title claims abstract description 47
- 230000001651 autotrophic effect Effects 0.000 title claims abstract description 28
- 239000000945 filler Substances 0.000 title claims abstract description 25
- 230000001105 regulatory effect Effects 0.000 title claims abstract description 20
- 230000001276 controlling effect Effects 0.000 title claims abstract description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 176
- MMDJDBSEMBIJBB-UHFFFAOYSA-N [O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[NH6+3] Chemical compound [O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O.[NH6+3] MMDJDBSEMBIJBB-UHFFFAOYSA-N 0.000 claims abstract description 100
- 239000000523 sample Substances 0.000 claims abstract description 8
- 239000005077 polysulfide Substances 0.000 claims description 7
- 229920001021 polysulfide Polymers 0.000 claims description 7
- 150000008117 polysulfides Polymers 0.000 claims description 7
- DHCDFWKWKRSZHF-UHFFFAOYSA-N sulfurothioic S-acid Chemical compound OS(O)(=O)=S DHCDFWKWKRSZHF-UHFFFAOYSA-N 0.000 claims description 6
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 5
- 241001365789 Oenanthe crocata Species 0.000 claims description 3
- 239000000758 substrate Substances 0.000 claims 2
- 239000002351 wastewater Substances 0.000 abstract description 11
- 238000006243 chemical reaction Methods 0.000 abstract description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 abstract description 8
- 239000001301 oxygen Substances 0.000 abstract description 8
- 239000007788 liquid Substances 0.000 abstract description 5
- 238000012806 monitoring device Methods 0.000 abstract description 2
- 239000010865 sewage Substances 0.000 description 31
- 230000033228 biological regulation Effects 0.000 description 26
- 239000000463 material Substances 0.000 description 20
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 12
- 229910052799 carbon Inorganic materials 0.000 description 12
- 230000008569 process Effects 0.000 description 12
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 230000009467 reduction Effects 0.000 description 10
- 230000014759 maintenance of location Effects 0.000 description 8
- 238000004065 wastewater treatment Methods 0.000 description 7
- 241000894006 Bacteria Species 0.000 description 6
- 238000012544 monitoring process Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000001914 filtration Methods 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 229910052979 sodium sulfide Inorganic materials 0.000 description 5
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 5
- 239000010802 sludge Substances 0.000 description 4
- HYHCSLBZRBJJCH-UHFFFAOYSA-N sodium polysulfide Chemical compound [Na+].S HYHCSLBZRBJJCH-UHFFFAOYSA-N 0.000 description 4
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 4
- 235000019345 sodium thiosulphate Nutrition 0.000 description 4
- 239000000969 carrier Substances 0.000 description 3
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-M Bicarbonate Chemical compound OC([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-M 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- MBMLMWLHJBBADN-UHFFFAOYSA-N Ferrous sulfide Chemical compound [Fe]=S MBMLMWLHJBBADN-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- JVMRPSJZNHXORP-UHFFFAOYSA-N ON=O.ON=O.ON=O.N Chemical compound ON=O.ON=O.ON=O.N JVMRPSJZNHXORP-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 241001509286 Thiobacillus denitrificans Species 0.000 description 1
- CKUAXEQHGKSLHN-UHFFFAOYSA-N [C].[N] Chemical compound [C].[N] CKUAXEQHGKSLHN-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- JGIATAMCQXIDNZ-UHFFFAOYSA-N calcium sulfide Chemical compound [Ca]=S JGIATAMCQXIDNZ-UHFFFAOYSA-N 0.000 description 1
- FAYYUXPSKDFLEC-UHFFFAOYSA-L calcium;dioxido-oxo-sulfanylidene-$l^{6}-sulfane Chemical compound [Ca+2].[O-]S([O-])(=O)=S FAYYUXPSKDFLEC-UHFFFAOYSA-L 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-M dihydrogenphosphate Chemical compound OP(O)([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-M 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 229960002089 ferrous chloride Drugs 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000011081 inoculation Methods 0.000 description 1
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 1
- QENHCSSJTJWZAL-UHFFFAOYSA-N magnesium sulfide Chemical compound [Mg+2].[S-2] QENHCSSJTJWZAL-UHFFFAOYSA-N 0.000 description 1
- 235000019341 magnesium sulphate Nutrition 0.000 description 1
- 229940062135 magnesium thiosulfate Drugs 0.000 description 1
- TZKHCTCLSRVZEY-UHFFFAOYSA-L magnesium;dioxido-oxo-sulfanylidene-$l^{6}-sulfane Chemical compound [Mg+2].[O-]S([O-])(=O)=S TZKHCTCLSRVZEY-UHFFFAOYSA-L 0.000 description 1
- 244000005700 microbiome Species 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 description 1
- 229910052683 pyrite Inorganic materials 0.000 description 1
- 239000011028 pyrite Substances 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/28—Anaerobic digestion processes
- C02F3/2806—Anaerobic processes using solid supports for microorganisms
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/28—Anaerobic digestion processes
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/28—Anaerobic digestion processes
- C02F3/2826—Anaerobic digestion processes using anaerobic filters
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/001—Upstream control, i.e. monitoring for predictive control
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/003—Downstream control, i.e. outlet monitoring, e.g. to check the treating agents, such as halogens or ozone, leaving the process
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/15—N03-N
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/42—Liquid level
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Microbiology (AREA)
- Biodiversity & Conservation Biology (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Abstract
The invention provides a method for directionally regulating and controlling a sulfur-based filler autotrophic denitrification filter, which realizes denitrification treatment of wastewater by regulating drop height, exposing a reaction bed and adding a sulfur source, in addition, a dissolved oxygen probe, a liquid level detector, a bed height monitor and a nitrate nitrogen on-line monitoring device are arranged in the denitrification filter, the nitrate nitrogen content of wastewater inlet and outlet water is monitored in real time, and the difference value of the two is calculated through a central control system, and compared with a set value, the drop height, the exposure reaction bed or the sulfur source is regulated and controlled in time.
Description
Technical Field
The invention relates to the field of sewage treatment and resource utilization, in particular to a method for controlling drop height, exposing a reaction bed layer and adding a sulfur source to directionally regulate and control a sulfur-based filler autotrophic denitrification filter.
Background
At present, the sewage discharge amount is gradually increased, the total nitrogen concentration in the sewage is higher and higher, the sewage discharge and treatment problems are increasingly prominent, the wide attention is brought to, and the sewage treatment is more and more urgent.
Among the processes for sewage treatment, biological sewage treatment technology is favored by many researchers because of its low cost and high treatment efficiency. However, as the total nitrogen concentration in the sewage discharged at present is higher and higher, the carbon nitrogen ratio is gradually unbalanced, so that the denitrification step of biological treatment is not carried out thoroughly, the phenomenon of water quality fluctuation often occurs, and the fluctuation of treatment effect is often caused, the conventional carbon source adding heterotrophic filter is changed into a sulfur-based filler autotrophic denitrification filter, but the sulfur-based filler autotrophic denitrification filter still can face the problem of fluctuation of treatment effect, and the current sulfur-based filler autotrophic denitrification filter does not have a method capable of carrying out load regulation.
The existing heterotrophic denitrification filter with the traditional carbon source is characterized in that the COD external carbon source is added as an electron donor, the nitrate nitrogen content in tail water is removed, and the denitrification load regulation and control are mainly realized by changing the addition amount of the COD external carbon source.
The sulfur-based filler autotrophic denitrification filter needs to throw the sulfur-based carrier into the filter in advance, so that the load control cannot be realized by changing the throwing amount of the COD external carbon source.
In addition, studies have demonstrated that dissolved oxygen reacts with electron donors as an electron acceptor in preference to nitrate.
For example: chinese patent CN 211311023U discloses a denitrification filter for reducing carbon source consumption. The dissolved oxygen in the sewage is removed to the maximum extent through the dissolved oxygen, so that the carbon source consumption in the sewage denitrification treatment process is reduced, but the device still needs to be additionally provided with a carbon source, so that the cost is increased, the denitrification level is poor when the carbon source is insufficient, and the sewage treatment effect is poor.
For example: application number 202011629562.4. The invention relates to a sewage treatment device with an intelligent monitoring backwash strengthening denitrification process, which comprises a first filter tank and a second filter tank, wherein the bottom end of one side of the first filter tank is connected with a sewage sample injection unit, the upper end of the other side of the first filter tank is connected with a connecting pipe, the other end of the connecting pipe is connected with the bottom end of one side of the second filter tank, and the upper end of the other side of the second filter tank is connected with a sewage sample outlet unit; a slow-release carbon source filler layer is arranged in the middle of the first filter tank, and a denitrifying bacteria filler layer is arranged in the middle of the second filter tank; the top of the first filter tank and the top of the second filter tank are respectively provided with a back flushing unit, and the bottoms of the first filter tank and the second filter tank are respectively provided with a back flushing discharge unit. The device strengthens the denitrification process by adding the carbon source in the water, enhances the degradation function of pollutants in the water body, realizes intelligent regulation and control through the sensor, is more convenient and simpler to operate, and greatly improves the nitrogen and phosphorus removal efficiency of the traditional treatment process. However, this patent still involves the problem of carbon source addition.
The sulfur autotrophic denitrification technology has good application prospect for advanced treatment of urban sewage due to the advantages of low running cost, small sludge yield and the like. However, the existing filter tank type process design method lacks effective regulation and control means for denitrification load in the running process and is difficult to adapt to the objective current situation of water quality fluctuation.
Disclosure of Invention
Based on the technical background, the inventor makes a keen approach, and found that: the method can realize denitrification treatment of wastewater by adjusting the drop height, exposing the reaction bed and adding a sulfur source, simultaneously, a dissolved oxygen probe, a liquid level detector, a bed height monitor and on-line nitrate nitrogen monitoring equipment are arranged in the denitrification filter tank, so that the real-time monitoring of the nitrate nitrogen concentration of wastewater inlet water can be realized, the content of nitrate nitrogen in wastewater is fed back in time, and the drop height, the exposure reaction bed and the sulfur source can be dynamically regulated and controlled.
The invention provides a method for directionally regulating and controlling the load of a sulfur-based filler autotrophic denitrification filter, which comprises one or more of controlling the height of an exposed bed, adjusting the height of drop water and adding a sulfur source.
The regulation and control method provided by the invention has the following advantages:
(1) The regulation and control method can obviously reduce the nitrogen content of the effluent and improve or reduce the removal efficiency of the nitrate nitrogen;
(2) The regulation and control method has low operation cost and high safety.
(3) The regulation and control method is convenient and simple through on-line control and real-time regulation and control.
Drawings
FIG. 1 shows a schematic structural diagram of a sulfur-based autotrophic denitrification fixed bed in accordance with a preferred embodiment of the present invention;
FIG. 2 shows a schematic process flow diagram of a method for directionally regulating and controlling a sulfur-based filler autotrophic denitrification filter in a preferred embodiment of the invention.
Description of the reference numerals
1-a water inlet main channel;
2-a water inlet gate;
3-a filter tank body;
4-a water and gas distribution system;
6-a filter material layer;
7-a supporting layer;
8-a water collecting channel;
9-water inlet channel;
11-filtering a water outlet pipe;
12-an air branch pipe;
13-catchment channel cover plate.
Detailed Description
The features and advantages of the present invention will become more apparent and evident from the following detailed description of the invention.
Aiming at the problems, the patent aims to establish a method for directionally regulating and controlling the denitrification load of the sulfur-based filler autotrophic denitrification filter by researching the influence rule of the sulfur-based filler bed load influence factor on the denitrification load of the sulfur-based filler autotrophic denitrification filter and correlating the influence rule with operation and control measures such as drop height, exposure reaction bed height, sulfur source addition and the like. Finally, a set of filter tank type sulfur autotrophic denitrification load directional regulation and control method is formed, and support is provided for the advanced treatment of the secondary biochemical tail water.
In the actual wastewater treatment process, stable removal of nitrate nitrogen content is a precondition for realizing stable operation of the sulfur-based filler autotrophic denitrification filter. Based on the technical problems, the invention provides a method for directionally regulating and controlling the load of a sulfur-based filler autotrophic denitrification filter, which is a wastewater treatment method with a feedback mode. The regulation and control method ensures that the treated wastewater has lower concentration and can reduce the wastewater treatment cost to the greatest extent.
The difference value of the nitrate nitrogen concentration of the inlet water and the outlet water refers to the difference value of the nitrate nitrogen concentration of the inlet water and the nitrate nitrogen concentration of the outlet water.
The invention provides a directional regulation and control method of a sulfur-based filler autotrophic denitrification filter, which comprises one or more of adjusting drop height, controlling the height of an exposed reaction bed layer and adding a sulfur source, so as to improve the wastewater treatment efficiency and effect, wherein the control method is used for regulating and controlling according to the difference value of nitrate nitrogen concentration of water inlet and water outlet. The method adopts a sulfur-based filler autotrophic denitrification filter to treat sewage.
No method for regulating and controlling the effective load of the bed denitrification is reported in the prior art. The exposed bed height refers to the bed height of a filter material layer in the exposed denitrification filter, the bed height of the filter material layer refers to the height of filling elemental sulfur or sulfur-based carriers, the percentage of the exposed bed height refers to the percentage of the bed height, the exposure is from top to bottom, and the accurate control of the exposed bed height is realized by controlling the size of a water outlet valve switch. The original water level of the sulfur-based filler autotrophic denitrification filter is level with the water inlet channel 9, the drop height refers to the vertical height from the actual water surface to the water inlet channel 9, and the liquid level height is controlled by adjusting the switch of the water outlet valve.
Adjusting the drop height includes increasing the height of the intake canal 9 to the actual water surface.
The sulfur source is selected from one or more of polysulfide, thiosulfate and sulfide.
The polysulfide is selected from one or more of calcium polysulfide, magnesium polysulfide and sodium polysulfide, preferably sodium polysulfide.
The thiosulfate is one or more selected from calcium thiosulfate, sodium thiosulfate and magnesium thiosulfate, and preferably sodium thiosulfate.
The sulfide is one or more selected from calcium sulfide, magnesium sulfide, sodium sulfide and iron sulfide, preferably sodium sulfide.
According to the invention, the target water inlet and outlet nitrate nitrogen concentration difference value is set as Xmg/L, and when regulation and control are carried out, the sulfur source is determined, one or more of the drop height and the exposed bed layer is controlled according to comparison between the actual water inlet and outlet nitrate nitrogen concentration difference value Ymg/L and the target water inlet and outlet nitrate nitrogen concentration difference value X, and the nitrate nitrogen reduction amount of the treated wastewater is controlled within a certain range.
The nitrate nitrogen reduction amount is the difference value of nitrate nitrogen concentration of water inlet and outlet, and refers to the difference value of nitrate nitrogen concentration of water inlet and nitrate nitrogen concentration of water outlet. In the invention, X is an arbitrary value in 3-20 mg/L, preferably an arbitrary value in 3-18 mg/L, more preferably an arbitrary value in 5-15 mg/L, and in the practical application process, the adjustment can be generally carried out within the range of adding or subtracting 2 on the basis of the X value, and the nitrate nitrogen concentration in the treated wastewater also fluctuates within a certain range, namely within the range of adding or subtracting 2 of the X value.
The original water level of the sulfur-based filler autotrophic denitrification filter is flush with the water inlet channel 9. In the sewage treatment process, the drop height is adjusted according to the actual difference value of the nitrate nitrogen concentration of the inlet water and the outlet water in the denitrification filter.
According to the invention, the target water inlet and outlet nitrate nitrogen concentration difference value is set, and on the basis, the regulation method can be determined by only comparing the actual water inlet and outlet nitrate nitrogen concentration difference value with the target water inlet and outlet nitrate nitrogen concentration difference value when the later regulation is carried out. Experiments show that the method is convenient for regulating and controlling the denitrification filter, is convenient for controlling the drop height, the exposure bed layer and the sulfur source addition, and ensures that the nitrate nitrogen concentration difference of the inlet and outlet water is controlled within a certain range. In a preferred embodiment of the present invention, the actual inlet-outlet nitrate nitrogen concentration difference is lower than the set target difference (i.e., the target inlet-outlet nitrate nitrogen concentration difference), and the wastewater treatment is achieved by adding a sulfur source, and if the actual inlet-outlet nitrate nitrogen concentration difference is higher than the set target difference, the wastewater treatment is achieved by increasing one or both of the drop height and the exposed bed. If the difference value of the nitrate nitrogen concentration of the inlet water is the same as the set value, no sulfur source is added, the drop height is not adjusted, and the bed layer is exposed.
The bed denitrification effective load regulation and control method can realize regulation and control in the high load direction and also realize directional regulation and control in the low load direction. If the difference value of the nitrate nitrogen concentration of the water inlet and the water outlet is larger than Xmg/L, the control is needed to be carried out under low load, and if the difference value of the nitrate nitrogen concentration of the water inlet and the water outlet is smaller than Xmg/L, the control is needed to be carried out under high load.
In a further preferred embodiment of the present invention, if the difference in the concentration of nitrate nitrogen in the actual water inlet and outlet is higher than the set target water inlet and outlet difference in the concentration of nitrate nitrogen and equal to or less than Amg/L (X < Y. Ltoreq.A), the drop height is increased.
Preferably, each time the actual water inlet and outlet nitrate nitrogen concentration difference is increased by 1mg/L of nitrate nitrogen relative to the set target water inlet and outlet nitrate nitrogen concentration difference, the drop height is increased by 0.01-0.5 m.
A is preferably 1.2X to 2X.
If the actual nitrate nitrogen concentration difference of the inlet water and the outlet water is higher than the set target difference and higher than Amg/L, the drop height is increased, and the bed layer is exposed.
Preferably, the drop height is increased to 1.5-3 m, the value obtained by subtracting A from the actual water inlet and outlet nitrate nitrogen concentration difference is increased by 0.1-10% for every 1mg/L of nitrate nitrogen, and the exposure height of the bed layer is increased until the bed layer is exposed to 100% of the initial value.
For example, the concentration difference of the actual inlet and outlet water nitrate nitrogen is 11mg/L, the concentration difference of the target inlet and outlet water nitrate nitrogen is set to be 6mg/L, namely, the actual inlet and outlet water nitrate nitrogen difference is increased by 5mg/L relative to the concentration difference of the set target inlet and outlet water nitrate nitrogen, and the drop height is set to be 1.2m.
For example, the actual nitrate nitrogen concentration difference of the inlet water and the outlet water is 19mg/L, the target nitrate nitrogen concentration difference of the inlet water and the outlet water is set to be 6mg/L, namely, the nitrate nitrogen difference of the inlet water and the outlet water is increased by 13mg/L relative to a set value and is higher than A (set to be 12 mg/L), the drop height is controlled to be 1.5m, and the bed layer is exposed by 30%.
In a further preferred embodiment of the present invention, if the actual inlet-outlet nitrate nitrogen concentration difference is lower than the set target difference, one or more of polysulfide 0.5-3 mg/L, thiosulfate 8-10 mg/L, sulfide 3-4 mg/L is added per 1mg/L reduction of nitrate nitrogen compared with the set target inlet-outlet nitrate nitrogen concentration difference. For example, the concentration difference of the actual nitrate nitrogen in water and the actual nitrate nitrogen in water is 3mg/L, the concentration difference of the target nitrate nitrogen in water and the target nitrate nitrogen in water is set to be 6mg/L, the concentration of the treated actual nitrate nitrogen in water and the treated nitrate nitrogen in water fluctuates within the range of 6+/-2 mg/L, namely, the concentration difference of the nitrate nitrogen in water and the nitrate nitrogen in water is reduced by 3mg/L relative to the set target difference, and sodium polysulfide is added by 3mg/L or sodium thiosulfate is added by 30mg/L or sodium sulfide is added by 9mg/L.
The sulfur-based filler autotrophic denitrification filter comprises a water inlet 1, a water inlet gate 2, a filter tank body 3, a water distribution and air distribution system 4, a filter material layer 6, a supporting layer 7, a water collecting channel 8, a water inlet channel 9 and a filtering water outlet pipe 11.
The water inlet 1, the water inlet gate 2 and the water inlet channel 9 are positioned above the filter material layer 6, and the water inlet 1 and the water inlet gate 2 are positioned on one side of the water inlet channel 9. The water inlet gate 2 is positioned between the water inlet 1 and the water inlet channel 9.
The supporting layer 7, the water collecting channel 8 and the filtering water outlet pipe 11 are positioned below the filter material layer 6, the supporting layer 7 is positioned between the filter material layer 6 and the water collecting channel 8, and the filtering water outlet pipe 11 is positioned on one side of the water collecting channel 8.
The vertical distance between the water inlet channel 9 and the filter layer 6 is 0-3 m, preferably 1.5-2.5 m, more preferably 1.5-2 m.
The denitrification filter further comprises an air branch pipe 12 and a water collecting channel cover plate 13, wherein the air branch pipe 12 and the water collecting channel cover plate 13 are positioned between the supporting layer 7 and the water collecting channel 8, and the air branch pipe 12 is positioned between the supporting layer 7 and the water collecting channel cover plate 13.
The denitrification filter also comprises a dissolved oxygen probe, a liquid level detector, a bed height monitor, a nitrate nitrogen on-line monitoring device and a water inlet dosing pipe.
The water inlet dosing pipe is used for dosing the sulfur source, and the online monitoring equipment of nitrate nitrogen is used for monitoring the concentration of nitrate nitrogen of intaking, is convenient for in time feeding back the concentration of nitrate nitrogen of intaking, as shown in figure 2, regulates and controls the bed exposure of denitrification filter, drop height and the quality of dosing the sulfur source.
The water inlet dosing pipe is arranged between the water inlet main canal 1 and the water inlet canal 9 and is positioned above the water inlet gate 2.
According to a preferred embodiment of the present invention, the filter material layer 6 includes one or several of elemental sulfur, pyrite and sulfur-based carriers, preferably includes one or two of elemental sulfur and sulfur-based carriers, more preferably includes elemental sulfur, and elemental sulfur adopted in the present invention is spherical.
The radius of the elemental sulfur is 1 to 15mm, preferably 3 to 10mm, more preferably 3 to 6mm.
The height of the filter layer 6 is 1 to 5m, preferably 1 to 4m, more preferably 1 to 3m.
The porosity of the filter layer 6 is 30% to 80%, preferably 30% to 70%, more preferably 30% to 60%.
The filter material layer 6 also comprises sulfur autotrophic denitrifying bacteria. The strain can quickly reduce nitrate nitrogen, nitrite nitrogen and the like in water into nitrogen. The bacteria in the filter pool are subjected to domestication by adding sludge in a biochemical anoxic pool to obtain sulfur autotrophic denitrifying bacteria such as thiobacillus denitrificans and the like.
The material of the supporting layer 7 is one or more selected from inert materials with rough surfaces, preferably one or more selected from stones, ceramsite and cobblestones, and more preferably cobblestones with diameters of 2-20 mm.
The porosity of the supporting layer 7 is 30% to 80%, preferably 30% to 70%, more preferably 30% to 60%. When the porosity of the supporting layer is within the above range, large particulate matters in the sewage can be filtered, and the large particulate matters in the sewage are prevented from entering the water collecting channel 8.
The domestication and film formation operation is a conventional operation in the field, for example, a proper amount of excess sludge of a sewage treatment plant can be inoculated into a sewage treatment system as an inoculation source, and then typical biological denitrification bacteria are domesticated by continuous water inflow, so that the biological film is formed on the surface of a slow-release electron donor in an attached growth manner, and the surface of the slow-release electron donor is a core area (a hot area) of biological denitrification reaction. In the domestication process, the formation of the biological film can be accelerated by adding reduced amount of dihydrogen phosphate, bicarbonate, thiosulfate, ferrous chloride, sodium chloride, magnesium sulfate, calcium chloride and microelements into the sewage containing nitrate.
The time for the wastewater to be treated to flow through the denitrification fixed bed is 10 to 60min, preferably 15 to 45min, more preferably 20 to 30min.
The invention has the beneficial effects that:
(1) The invention can realize high-load regulation and control and also realize low-load regulation and control by controlling the drop height, exposing the bed layer and adding the sulfur source regulation and control method;
(2) According to the invention, drop water, sulfur source throwing and bed layer exposure are regulated and controlled in a feedback manner, so that the nitrate nitrogen concentration reduction amount of the treated wastewater can be effectively controlled within a certain range, the wastewater treatment effect is improved, and the treatment cost is reduced;
(3) When the difference value of the nitrate nitrogen concentration of the water inlet and outlet is higher than a set value, the denitrification load is reduced by falling water to enrich oxygen or exposing the reaction bed layer, so that the consumption of elemental sulfur is saved, and the sewage treatment cost is reduced.
Examples
The invention is further illustrated by the following specific examples, which are intended to be illustrative of the invention and are not intended to limit the scope of the invention.
Example 1
The composition of the wastewater is as follows: NO (NO) 3 -N (addition of KNO) 3 )，20mg/L；K 2 HPO 4 ·3H 2 O，5mg/L；NH 4 Cl 1mg/L；FeSO 4 ·7H 2 O，1mg/L；NaHCO 3 60mg/L。
The sulfur-based filler autotrophic denitrification filter is inoculated with 500mL of anoxic Chi Wuni (the sludge concentration is about 5000 mg/L) from a north sewage treatment plant in Beijing city, and the filter is subjected to microorganism domestication before a formal experiment and then continuously operates under the condition of 20min of empty bed retention time. The pH of the inlet water is controlled between 7 and 8, and the reaction temperature is about 20 ℃.
The sulfur-based filler autotrophic denitrification filter comprises a water inlet 1, a water inlet gate 2, a filter tank body 3, a water distribution and air distribution system 4, a filter material layer 6, a supporting layer 7, a water collecting channel 8, a water inlet channel 9 and a filtering water outlet pipe 11, wherein the water inlet 1, the water inlet gate 2 and the water inlet channel 9 are positioned above the filter material layer 6, the vertical distance between the water inlet channel 9 and the filter material layer 6 is 1.5m, and the water inlet 1 and the water inlet gate 2 are positioned on the same side of the water inlet channel 9 as shown in figure 1. The water inlet gate 2 is positioned between the water inlet 1 and the water inlet channel 9. The support layer 7, the water collecting channel 8 and the filtered water outlet pipe 11 are positioned below the filter material layer 6, the support layer 7 is positioned between the filter material layer 6 and the water collecting channel 8, the filtered water outlet pipe 11 is positioned on one side of the water collecting channel 8, the denitrification filter further comprises an air branch pipe 12 and a water collecting channel cover plate 13, the air branch pipe 12 and the water collecting channel cover plate 13 are positioned between the support layer 7 and the water collecting channel 8, and the air branch pipe 12 is positioned between the support layer 7 and the water collecting channel cover plate 13. The denitrification filter further comprises a dissolved oxygen probe, a liquid level detector, a bed height monitor, nitrate nitrogen on-line monitoring equipment and a water inlet dosing pipe, wherein the water inlet dosing pipe is arranged between the water inlet 1 and the water inlet channel 9 and is positioned above the water inlet gate 2, the material of the supporting layer 7 is cobbles with the thickness of 2-20 mm, the porosity of the supporting layer 7 is 50%, the filter material layer 6 comprises sulfur simple substances and sulfur autotrophic denitrification bacteria, the radius of the sulfur simple substances is 3-6 mm, the height of the filter material layer 6 is 1.2m, the porosity of the filter material layer 6 is 41%, the target inlet and outlet water nitrate nitrogen concentration difference value is set to be 6mg/L, the value of A is 12mg/L, the actual inlet and outlet water nitrate nitrogen concentration difference value is monitored to be 20mg/L, the drop height is controlled to be 1.5m, the exposure bed layer is 40%, and the inlet and outlet water nitrate nitrogen concentration difference value after regulation is 4-8 mg/L.
Example 2
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the actual water inlet and outlet nitrate nitrogen concentration difference value is monitored to be 3mg/L, 30mg/L of sodium thiosulfate is added into the inlet water, and the water inlet and outlet nitrate nitrogen concentration difference value after regulation is 4-8 mg/L.
Example 3
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 2mg/L, 12mg/L of sodium sulfide is added into the water inlet, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration is regulated to be 4-8 mg/L.
Example 4
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 1mg/L, 20mg/L of sodium sulfide is added into the water inlet, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration is regulated to be 4-8 mg/L.
Example 5
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 1mg/L, sodium polysulfide is added to the water inlet for 3mg/L, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration is regulated to be 4-8 mg/L.
Example 6
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 9mg/L, no sulfur source is added, the drop height is increased by 1.2m, no bed layer exposure is regulated and controlled, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration after regulation is 4-8 mg/L.
Example 7
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 10mg/L, no sulfur source is added, the drop height is increased by 1.4m, no bed layer exposure is regulated and controlled, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration after regulation is 4-8 mg/L.
Example 8
Sewage denitrification was performed in a similar manner to example 1, except that: under the condition of 20min of empty bed retention time, the difference value of the actual water inlet and outlet nitrate nitrogen concentration is monitored to be 13mg/L, a sulfur source is not added, the drop height is controlled to be 1.5m, the exposed bed layer is 10%, and the reduction amount of the water inlet and outlet nitrate nitrogen concentration after regulation is 4-8 mg/L.
The invention has been described in detail in connection with the specific embodiments and exemplary examples thereof, but such description is not to be construed as limiting the invention. It will be understood by those skilled in the art that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, and these fall within the scope of the present invention. The scope of the invention is defined by the appended claims.
Claims (10)
1. A method for directionally regulating and controlling the load of a sulfur-based filler autotrophic denitrification filter is characterized by comprising one or more of controlling the height of an exposed bed, adjusting the height of drop water and adding a sulfur source.
2. The method of claim 1, wherein the sulfur source is selected from one or more of polysulfide, thiosulfate, sulfide.
3. The method of claim 1, wherein the step of determining the position of the substrate comprises,
the actual water inlet and outlet nitrate nitrogen concentration difference value is higher than the target water inlet and outlet nitrate nitrogen concentration difference value, and one or two of the drop height and the exposed bed layer are increased; the actual water inlet and outlet nitrate nitrogen concentration difference value is lower than the set target water inlet and outlet nitrate nitrogen concentration difference value, and a sulfur source is added.
4. A method according to claim 3, wherein the actual inlet-outlet water nitrate nitrogen concentration difference is monitored to be Ymg/L, and the target inlet-outlet water nitrate nitrogen concentration difference is set to be Xmg/L;
x is any value of 3-20 mg/L.
5. The method of claim 4, wherein the step of determining the position of the first electrode is performed,
the actual water inlet and outlet nitrate nitrogen concentration difference is higher than the set target water inlet and outlet nitrate nitrogen concentration difference and is smaller than or equal to Amg/L (X < Y is less than or equal to A), and the drop height is increased.
6. The method of claim 5, wherein the step of determining the position of the probe is performed,
every 1mg/L of the actual water inlet and outlet nitrate nitrogen concentration difference value is increased relative to the set target water inlet and outlet nitrate nitrogen concentration difference value, the drop height is increased by 0.01-0.5 m.
7. The method of claim 4, wherein the step of determining the position of the first electrode is performed,
the actual water inlet and outlet nitrate nitrogen concentration difference is higher than the set target water inlet and outlet nitrate nitrogen concentration difference and is higher than Amg/L (Y > A), the drop height is increased, and the bed layer is exposed.
8. The method of claim 7, wherein the step of determining the position of the probe is performed,
the drop height is increased to 1.5-3 m, the difference value of Amg/L is subtracted from the actual water inlet and outlet nitrate nitrogen concentration difference value, and the bed exposure height is increased by 0.1-10% when 1mg/L is added until the bed is exposed to 100%.
9. The method of claim 4, wherein the step of determining the position of the first electrode is performed,
the actual water inlet and outlet nitrate nitrogen concentration difference is lower than the set target water inlet and outlet nitrate nitrogen concentration difference (Y < X), and a sulfur source is added.
10. The method of claim 9, wherein the step of determining the position of the substrate comprises,
and (3) adding one or more of polysulfide 0.5-3 mg/L, thiosulfate 8-10 mg/L and sulfide 3-4 mg/L into the actual water inlet and outlet nitrate nitrogen concentration difference, wherein the difference is smaller than the set target water inlet and outlet nitrate nitrogen concentration difference by 1 mg/L.
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| CN202210879167.4A CN117326688A (en) | 2022-07-25 | 2022-07-25 | Method for directionally regulating and controlling sulfur-based filler autotrophic denitrification filter |
| PCT/CN2022/136037 WO2024021422A1 (en) | 2022-07-25 | 2022-12-01 | Method for directionally regulating sulfur-based filler autotrophic denitrification filter |
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| JP4327770B2 (en) * | 2005-06-16 | 2009-09-09 | 株式会社神鋼環境ソリューション | Biological nitrification treatment method and nitrification treatment apparatus for wastewater containing ammonia nitrogen |
| CN201010580Y (en) * | 2007-02-01 | 2008-01-23 | 北京工业大学 | Hypoxia aerating controlling device of segmented water-feeding A/O biological denitrification technique |
| DE102009011490A1 (en) * | 2008-12-11 | 2010-06-17 | Envicon Klärtechnik Verwaltungsgesellschaft mbH | Process for the load-dependent control of nitrification and denitrification in wastewater treatment plants with upstream denitrification |
| CN111704239A (en) * | 2020-06-19 | 2020-09-25 | 中清信益环境(南京)有限公司 | Efficient denitrification filter tank system and working method |
| CN214734805U (en) * | 2021-03-12 | 2021-11-16 | 国环科技发展(湖北)有限公司 | Water inlet device of denitrification deep bed filter |
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