CN111320323A - Treatment method of high-total-nitrogen leather wastewater - Google Patents
Treatment method of high-total-nitrogen leather wastewater Download PDFInfo
- Publication number
- CN111320323A CN111320323A CN202010123749.0A CN202010123749A CN111320323A CN 111320323 A CN111320323 A CN 111320323A CN 202010123749 A CN202010123749 A CN 202010123749A CN 111320323 A CN111320323 A CN 111320323A
- Authority
- CN
- China
- Prior art keywords
- tank
- treatment
- aerobic tank
- wastewater
- aerobic
- 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
Links
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 title claims abstract description 78
- 238000000034 method Methods 0.000 title claims abstract description 74
- 239000002351 wastewater Substances 0.000 title claims abstract description 73
- 239000010985 leather Substances 0.000 title claims abstract description 52
- 229910052757 nitrogen Inorganic materials 0.000 title claims abstract description 43
- 239000010802 sludge Substances 0.000 claims abstract description 52
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 48
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 48
- 238000004062 sedimentation Methods 0.000 claims abstract description 42
- 230000008569 process Effects 0.000 claims abstract description 33
- 239000000945 filler Substances 0.000 claims abstract description 28
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 47
- 229910052760 oxygen Inorganic materials 0.000 claims description 47
- 239000001301 oxygen Substances 0.000 claims description 47
- 230000014759 maintenance of location Effects 0.000 claims description 40
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 claims description 35
- 230000015556 catabolic process Effects 0.000 claims description 15
- 238000006731 degradation reaction Methods 0.000 claims description 15
- JVMRPSJZNHXORP-UHFFFAOYSA-N ON=O.ON=O.ON=O.N Chemical compound ON=O.ON=O.ON=O.N JVMRPSJZNHXORP-UHFFFAOYSA-N 0.000 claims description 13
- 238000009825 accumulation Methods 0.000 claims description 13
- 238000010992 reflux Methods 0.000 claims description 11
- 239000011435 rock Substances 0.000 claims description 10
- 229920005830 Polyurethane Foam Polymers 0.000 claims description 9
- 239000011496 polyurethane foam Substances 0.000 claims description 9
- 238000011001 backwashing Methods 0.000 claims description 8
- 230000035800 maturation Effects 0.000 claims description 2
- 230000000737 periodic effect Effects 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 16
- 238000005265 energy consumption Methods 0.000 abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 23
- 238000012545 processing Methods 0.000 description 15
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 12
- 238000005273 aeration Methods 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 12
- 230000001276 controlling effect Effects 0.000 description 12
- 239000000126 substance Substances 0.000 description 10
- 241000894006 Bacteria Species 0.000 description 8
- 210000004209 hair Anatomy 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 239000006228 supernatant Substances 0.000 description 8
- 239000007788 liquid Substances 0.000 description 7
- 230000001546 nitrifying effect Effects 0.000 description 7
- 238000004065 wastewater treatment Methods 0.000 description 7
- 229910000029 sodium carbonate Inorganic materials 0.000 description 6
- 235000017550 sodium carbonate Nutrition 0.000 description 6
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 244000005700 microbiome Species 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 239000003403 water pollutant Substances 0.000 description 3
- 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
- 230000008859 change Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000003344 environmental pollutant Substances 0.000 description 2
- 230000004807 localization Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 231100000719 pollutant Toxicity 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 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 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000006396 nitration reaction Methods 0.000 description 1
- YPJKMVATUPSWOH-UHFFFAOYSA-N nitrooxidanyl Chemical compound [O][N+]([O-])=O YPJKMVATUPSWOH-UHFFFAOYSA-N 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
Images
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
- C02F3/30—Aerobic and anaerobic processes
- C02F3/302—Nitrification and denitrification treatment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
-
- 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
- C02F3/02—Aerobic processes
- C02F3/10—Packings; Fillings; Grids
- C02F3/105—Characterized by the chemical composition
- C02F3/107—Inorganic materials, e.g. sand, silicates
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/22—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof
- C02F2103/24—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof from tanneries
-
- 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
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
-
- 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
- C02F2209/16—Total nitrogen (tkN-N)
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2305/00—Use of specific compounds during water treatment
- C02F2305/06—Nutrients for stimulating the growth of microorganisms
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Water Supply & Treatment (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (AREA)
- Microbiology (AREA)
- Biodiversity & Conservation Biology (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Abstract
The invention provides a method for treating leather wastewater with high total nitrogen. The method provided by the invention adopts the anoxic tank and the aerobic tank to start and operate the short-cut nitrification and denitrification process, adopts intermittent flow to add an external carbon source and then removes organic matters and total nitrogen under the condition of lower C/N, and adopts the biological aerated filter to further remove COD, total nitrogen and suspended matters, thereby realizing the treatment of wastewater. Specifically, after the aerobic tank is controlled to start short-cut nitrification to a certain degree under specific conditions, the leather wastewater is sequentially subjected to anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment, so that the leather wastewater is treated; in operation, the aerobic tank and the anoxic tank are controlled to quickly and fully realize nitrification and denitrification under specific operation conditions, so that the treatment effect is improved, and the energy consumption is reduced. Meanwhile, a certain amount of specific filler is added into the aerobic tank and the anoxic tank and is matched with field sludge discharge, so that the total nitrogen treatment capacity of the biochemical system can be effectively improved.
Description
Technical Field
The invention relates to the technical field of wastewater treatment, in particular to a method for treating high-total-nitrogen leather wastewater.
Background
With the development of the leather-making industry, high total nitrogen becomes a primary problem restricting the leather wastewater treatment work. At present, more methods are used for treating ammonia nitrogen wastewater, but due to the difference of different wastewater properties, adaptive and effective treatment processes must be developed according to the properties, components and other characteristics of different industrial wastewater.
At present, the annual discharge amount of leather factories in China reaches ten thousand tons, and the leather wastewater has the characteristics that: with a high concentration of S2-And Cr3+High COD concentration, high ammonia nitrogen concentration and poor biodegradability, and contains a large amount of neutral salts such as chloride, sulfate and the like.
Compared with the traditional biological denitrification, the short-cut nitrification and denitrification is a new biological denitrification process, and particularly, the two stages of nitrification (ammonia nitrogen is converted into nitrate radical) and denitrification (nitrate is converted into nitrogen) are mainly carried out, so that the process is complex, and if the two stages cannot be matched with each other well and react fully, the ammonia nitrogen cannot be removed effectively. The biochemical treatment method for leather wastewater in the prior art mainly comprises an anaerobic-aerobic method, an anaerobic-anoxic-aerobic method and the like, and compared with the traditional aerobic activated sludge method, the methods can improve the removal effect of ammonia nitrogen and COD in water. However, the above method generally has the problems of long total retention time, large floor area, high operation cost, low removal rate (ammonia nitrogen removal rate is less than 80%) and the like when treating leather wastewater with high ammonia nitrogen concentration, high COD concentration and poor biodegradability.
Disclosure of Invention
In view of the above, the present invention aims to provide a method for treating leather wastewater with high total nitrogen content. The treatment method provided by the invention can effectively improve the treatment efficiency of the leather wastewater and reduce the energy consumption and the cost.
The invention provides a method for treating high-total-nitrogen leather wastewater, which comprises the following steps of:
controlling the aerobic tank condition to start short-cut nitrification until the short-cut nitrification is mature, and sequentially carrying out anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment on the leather wastewater to obtain treated wastewater;
the conditions of the aerobic tank for starting the short-cut nitrification are as follows: the dissolved oxygen is 1.0-2.5 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 12-48 h;
the operating conditions of the aerobic tank treatment are as follows: the dissolved oxygen is 0.5-3 mg/L, the temperature is 25-35 ℃, the pH value is 7.0-8.5, and the hydraulic retention time is 12-48 h;
the adding amount of an external carbon source in the anoxic pond treatment is controlled to enable the C/N ratio of the anoxic pond to be 2.5-3.5;
biological fillers are added in the anoxic tank and the aerobic tank.
Preferably, the indexes of the short-cut nitrification maturation are as follows: the degradation rate of ammonia nitrogen is 200-600 mg/L.d, and the accumulation rate of nitrite nitrogen in the effluent of the aerobic tank is more than or equal to 80%.
Preferably, the operating conditions of the anoxic pond treatment are as follows: the dissolved oxygen is 0.1-0.3 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 14-28 h.
Preferably, the reflux ratio of the aerobic tank treatment is 100-300%.
Preferably, the biological filler is polyurethane foam;
the total nitrogen content of the leather wastewater is 800-1500 mg/L, and the COD is 800-1500 mg/L;
preferably, the adding amount of the biological filler is as follows: the volume of the biological filler accounts for 30 percent of the volume of the tank body.
Preferably, the adding mode of the carbon source is intermittent feeding;
the intermittent feeding comprises the following specific operations: 60 wt% of the total amount of the carbon source is added in the first 6-12 h, 30 wt% of the total amount of the carbon source is added after 2-4 h intervals, and the rest 10 wt% is added after 1-2 h intervals.
Preferably, the residence time of the secondary sedimentation tank treatment is 9-20 h.
Preferably, the filler in the biological filter is volcanic rock;
the volume of the volcanic rock accounts for 40-60% of the volume of the tank body;
the conditions of the biological filter tank treatment are as follows: 4-10 mg/L of dissolved oxygen, 6.5-8.5 of pH and 36-72 h/time of backwashing frequency.
Preferably, sludge is periodically discharged in the leather wastewater treatment process, so that the sludge SV30 of the aerobic pool is controlled to be 20-30%.
The method provided by the invention adopts the anoxic tank and the aerobic tank to start and operate the short-cut nitrification and denitrification process, adopts intermittent flow to add an external carbon source and then removes organic matters and total nitrogen under the condition of lower C/N, and adopts the biological aerated filter to further remove COD, total nitrogen and suspended matters, thereby realizing the treatment of wastewater. Specifically, the aerobic tank is controlled to start short-cut nitrification under specific conditions, and after a certain degree, the leather wastewater is sequentially subjected to anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment, so that the leather wastewater is treated; in operation, the aerobic tank and the anoxic tank are controlled to quickly and fully realize nitrification and denitrification under specific operation conditions, so that the treatment effect is improved, and the energy consumption is reduced. Meanwhile, a certain amount of specific filler is added into the aerobic tank and the anoxic tank and is matched with field sludge discharge, so that the ammonia nitrogen degradation capability and the denitrification capability of the aerobic tank and the denitrification capability of the anoxic tank can be effectively improved, and the total nitrogen treatment capability of a biochemical system is improved. In addition, the treatment method provided by the invention does not need complex equipment, only needs to be modified and upgraded on the basis of the original biochemical system, and saves the capital construction land occupation and the extension cost on the basis of solving the problem that the total nitrogen emission exceeds the standard.
Test results show that the treatment method provided by the invention can enable the effluent COD, ammonia nitrogen and total nitrogen of the leather wastewater discharge water to reach the GB 30486-2013 discharge standard of water pollutants for leather-making and fur processing industries; the nitrite state accumulation rate reaches more than 80 percent. Meanwhile, the treatment method disclosed by the invention does not need to additionally add an alkalinity agent, the consumption of the carbon source and the power consumption are obviously reduced, the daily treatment load of the system is obviously improved, and the high-efficiency, low-cost and low-energy-consumption treatment of the high-total-nitrogen leather wastewater is realized.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a flow chart of leather wastewater treatment process provided by the invention.
Detailed Description
The invention provides a method for treating high-total-nitrogen leather wastewater, which comprises the following steps of:
controlling the aerobic tank condition to start short-cut nitrification until the short-cut nitrification is mature, and sequentially carrying out anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment on the leather wastewater to obtain treated wastewater;
the conditions of the aerobic tank for starting the short-cut nitrification are as follows: the dissolved oxygen is 1.0-2.5 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 12-48 h;
the operating conditions of the aerobic tank treatment are as follows: the dissolved oxygen is 0.5-3 mg/L, the temperature is 25-35 ℃, the pH value is 7.0-8.5, and the hydraulic retention time is 12-48 h;
the adding amount of an external carbon source in the anoxic pond treatment is controlled to enable the C/N ratio of the anoxic pond to be 2.5-3.5;
biological fillers are added in the anoxic tank and the aerobic tank.
The method provided by the invention adopts the anoxic tank and the aerobic tank to start and operate the short-cut nitrification and denitrification process, adopts intermittent flow to add an external carbon source and then removes organic matters and total nitrogen under the condition of lower C/N, and adopts the biological aerated filter to further remove COD, total nitrogen and suspended matters, thereby realizing the treatment of wastewater. Specifically, the aerobic tank is controlled to start short-cut nitrification under specific conditions, and after a certain degree, the leather wastewater is sequentially subjected to anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment, so that the leather wastewater is treated; in operation, the aerobic tank and the anoxic tank are controlled to quickly and fully realize nitrification and denitrification under specific operation conditions, so that the treatment effect is improved, and the energy consumption is reduced. Meanwhile, a certain amount of specific filler is added into the aerobic tank and the anoxic tank and is matched with field sludge discharge, so that the ammonia nitrogen degradation capability and the denitrification capability of the aerobic tank and the denitrification capability of the anoxic tank can be effectively improved, and the total nitrogen treatment capability of a biochemical system is improved. In addition, the treatment method provided by the invention does not need complex equipment, only needs to be modified and upgraded on the basis of the original biochemical system, and saves the capital construction land occupation and the extension cost on the basis of solving the problem that the total nitrogen emission exceeds the standard.
According to the invention, the processing method comprises the following steps: controlling the aerobic tank condition to start short-cut nitrification until the short-cut nitrification is mature, and sequentially carrying out anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment on the leather wastewater to obtain treated wastewater.
In the invention, the leather wastewater to be treated is preferably leather wastewater with the following parameter indexes: the total nitrogen content is 800-1500 mg/L, and the COD is 800-1500 mg/L.
More preferably, the leather wastewater has the following characteristics: COD is 800-1500 mg/L, total nitrogen content is 800-1500 mg/L, ammonia nitrogen content is 600-1000 mg/L, suspended matter content is 1000-1500mg/L, and pH is 8-12. In some embodiments of the invention, the leather wastewater treated is: average COD is 1000mg/L, ammonia nitrogen concentration is 800-1000 mg/L, total nitrogen concentration is 1000-1500mg/L, suspended matter is 1000-1500mg/L, and pH is 8-10. In other embodiments of the present invention, the leather wastewater treated is: the average COD is 1500mg/L, the ammonia nitrogen concentration is 600-800 mg/L, the total nitrogen concentration is 800-1000 mg/L, the suspended matter content is 1200-1500mg/L, and the pH value is 10-12.
In the invention, the conditions of the aerobic tank are firstly controlled to start the short-cut nitrification, and the starting conditions are specifically as follows: the dissolved oxygen is 1.0-2.5 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 12-48 h. In some embodiments of the present invention, the dissolved oxygen is controlled to be 1.0-1.5 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 12-20 h. In other embodiments of the present invention, the dissolved oxygen is controlled to be 1.5-2.5 mg/L, the pH value is 7.5-8.0, and the hydraulic retention time is 24-48 h. The treatment effect is favorably improved under the conditions, if the dissolved oxygen or the pH value is too low, the ammonia nitrogen cannot be degraded or the ammonia nitrogen degradation efficiency is low, and if the dissolved oxygen is too high, the nitrite nitrogen accumulation rate can be reduced or even not accumulated. Too long water conservancy residence time can also cause nitrite nitrogen accumulation rate to reduce or even not accumulate, and too short ammonia nitrogen degradation is insufficient, can lead to the effluent ammonia nitrogen unqualified. Wherein, the dissolved oxygen is regulated and controlled by an aeration system; the pH is maintained by adding an alkaline substance, preferably soda ash. The hydraulic retention time is regulated and controlled by regulating the water inflow of the system.
In the invention, after the short-cut nitrification is started until the short-cut nitrification is mature, the leather wastewater is treated. In the invention, the indexes for controlling the shortcut nitrification maturity are as follows: the degradation rate of ammonia nitrogen is 200-600 mg/L.d, and the accumulation rate of nitrite nitrogen in the effluent of the aerobic tank is more than or equal to 80%. The short-cut nitrification starting process is characterized in that original activated sludge in the aerobic tank is utilized, the optimal growth condition is provided for short-cut nitrifying bacteria by controlling the water inflow and the process conditions of the aerobic tank, the short-cut nitrifying bacteria become dominant bacteria gradually, and the water inflow of the system can be gradually restored after the start is finished.
In the invention, after the short-range nitration is mature, the leather wastewater is treated as follows: the leather wastewater is sequentially treated by an anoxic tank, an aerobic tank, a secondary sedimentation tank and a biological filter. The above treatment process is shown in figure 1, and figure 1 is a process flow chart of the leather wastewater treatment process provided by the invention.
In the present invention, the leather wastewater is pretreated before the above treatment. In the invention, the pretreatment is preferably primary sedimentation treatment, specifically, wastewater is introduced into a primary sedimentation tank to remove large-particle substances such as animal fur and the like and a part of suspended matters, and the obtained supernatant is used as pretreated effluent to enter a subsequent treatment procedure.
In the invention, the pretreated effluent firstly enters the anoxic tank. In the invention, the flow pushing device is preferably arranged in the anoxic tank, so that the sludge-water mixture can be fully mixed under the condition of dissolved oxygen. In the invention, the anoxic tank is provided with a nitrifying liquid water inlet which is communicated with the aerobic tank, so that part of nitrifying liquid generated by the aerobic tank flows back into the anoxic tank to provide raw materials for denitrification. In the invention, the anoxic tank is also provided with an external carbon source adding port, particularly can be arranged on a nitrifying liquid water inlet pipeline, and the carbon source is added into the anoxic tank through the adding port to control the C/N ratio (namely the mass ratio of COD (chemical oxygen demand)/TN (total nitrogen)) in the tank.
Wherein the carbon source is preferably glucose. The adding amount of the carbon source is preferably selected to enable the C/N ratio of the sludge-water mixture in the anoxic pond to reach 2.5-3.5. In some embodiments of the invention, the C/N ratio is 2.5, 3.0, or 3.5.
Wherein, the adding mode of the carbon source is preferably intermittent feeding. The intermittent feeding comprises the following specific operations: 60 wt% of the total amount of the carbon source is added in the first 6-12 h, 30 wt% of the total amount of the carbon source is added after 2-4 h intervals, and the rest 10 wt% is added after 1-2 h intervals. In some embodiments of the invention, 60 wt% of the total amount of carbon source is added in the first 6 hours, 30 wt% of the total amount of carbon source is added after 2 hours, and the remaining 10 wt% is added after 1 hour. In other embodiments of the present invention, 60 wt% of the total amount of carbon source is added in the first 12 hours, 30 wt% of the total amount of carbon source is added after 4 hours, and the remaining 10 wt% is added after 2 hours. The intermittent flow addition is a unique adding mode of the invention, and the adding mode is innovated by the applicant through long-term research on the denitrification process, so that the full utilization of the carbon source can be ensured, the adding amount of the carbon source can be reduced, and the full utilization of the carbon source can be ensured.
Wherein, the operating conditions of the anoxic pond are preferably as follows: the dissolved oxygen is 0.1-0.3 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 14-28 h. In some embodiments of the invention, the dissolved oxygen is 0.1mg/L, 0.2mg/L, or 0.3 mg/L; the pH value is 7.0, 7.5 or 8.0; the hydraulic retention time is 14h, 16h, 18h or 19 h.
In the invention, the effluent of the anoxic tank enters the aerobic tank for aerobic treatment, the nitrite bacteria are in an dominant position after the aerobic tank starts a short-cut nitrification process, the conversion of ammonia nitrogen into nitrite nitrogen can be rapidly realized, the nitrate bacteria are in a disadvantaged position, the conversion of nitrite nitrogen into nitrate nitrogen is limited, and further the nitrite nitrogen is rapidly accumulated. The water outlet of the aerobic tank is provided with a nitrifying liquid reflux pump which is communicated with the anoxic tank and used for refluxing the nitrifying liquid to the anoxic tank.
Wherein, the operating conditions of the aerobic tank treatment are as follows: the dissolved oxygen is 0.5-3 mg/L, the temperature is 25-35 ℃, the pH value is 7.0-8.5, and the hydraulic retention time is 12-48 h. In some embodiments of the invention, the dissolved oxygen is 0.5mg/L, 1.5mg/L, 2.5mg/L, or 3 mg/L; the temperature is 25 ℃, 30 ℃ or 35 ℃; a pH of 7.0, 7.5, 8.0 or 8.5; the hydraulic retention time is 24h, 28h, 33h, 34h or 37 h. The aerobic tank and the anoxic tank are controlled under the specific operating conditions, so that nitrification and denitrification can be quickly and fully realized, the treatment effect is improved, the energy consumption is reduced, and if the parameters of all parameters are too low or too high, the treatment effect is influenced, and the energy consumption is increased.
Wherein the reflux ratio of the aerobic tank is preferably 100 to 300 percent. In some embodiments of the invention, the reflux ratio is 120%, 150%, 180%, or 250%.
In the invention, biological fillers are added in both the anoxic tank and the aerobic tank. The biological filler is preferably a polyurethane foam. The adding amount of the polyurethane foam is preferably 30% of the volume of the filler. In the invention, in the operation of the system, the secondary sedimentation tank periodically discharges sludge to avoid sludge discharge caused by overhigh sludge surface, the sludge discharge amount is controlled according to the SV30 of the secondary sedimentation tank, and the SV30 of the aerobic tank is ensured to be controlled at 20-30%; in some embodiments of the invention, sludge SV30 is controlled at 20%, 25%, or 30%. The biological filler is added into the aerobic tank and the anoxic tank, so that a growth carrier is provided for microorganisms, effective microorganisms can be intercepted to the maximum extent, and meanwhile, the effective bacteria proportion in a biochemical system can be continuously improved by matching with continuous field sludge discharge, the ammonia nitrogen degradation capability of the aerobic tank can be improved by 100-200%, the denitrification capability of the anoxic tank can be improved by more than 50%, and the guarantee is provided for the treatment of high total nitrogen wastewater.
In the invention, the effluent of the aerobic tank enters a secondary sedimentation tank, sludge is precipitated to the bottom through sedimentation and separation, and the effluent is sent to the next working procedure. In the invention, the preferred residence time of the secondary sedimentation tank is 9-20 h; in some embodiments of the invention, the residence time is 9h, 10h, 15h, or 20 h.
In the invention, the effluent of the secondary sedimentation tank enters the biological aerated filter for treatment. In the invention, the filler in the biological aerated filter is preferably volcanic rock, which not only can provide attachment sites for the growth of microorganisms, but also can further filter wastewater. In the invention, the adding amount of the filler is preferably 40-60% of the volume of the filler. The conditions of the biological aerated filter are as follows: 4-10 mg/L of dissolved oxygen, 6.5-8.5 of pH and 36-72 h/time of backwashing frequency. After being treated by the biological aerated filter, the treated wastewater is obtained and reaches the discharge standard.
The treatment method provided by the invention has the following beneficial effects:
1. the invention controls the aerobic tank to start short-cut nitrification under specific conditions, and then performs operation treatment on the leather wastewater to a certain extent, and controls the aerobic tank and the anoxic tank to rapidly and fully realize nitrification and denitrification under specific operation conditions in the operation treatment, thereby improving the treatment effect and reducing the energy consumption.
2. And a certain amount of specific filler is added into the aerobic tank and the anoxic tank and is matched with field sludge discharge, so that the ammonia nitrogen degradation capability of the aerobic tank and the denitrification capability of the anoxic tank can be effectively improved, wherein the ammonia nitrogen degradation capability of the aerobic tank can be improved by 100-200%, the denitrification capability of the anoxic tank can be improved by more than 50%, and the total nitrogen treatment capability of the biochemical system is effectively improved.
3. The treatment method of the invention reduces the overall energy consumption and cost, and reduces the operation cost of wastewater treatment by more than 30%.
4. The treatment method provided by the invention does not need complex equipment, only needs to be modified and upgraded on the basis of the original biochemical system, and saves the capital construction floor area and the extension cost on the basis of solving the problem that the total nitrogen emission exceeds the standard.
For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention by way of example, and it is to be understood that the description is intended to further illustrate features and advantages of the invention, and not to limit the scope of the claims. In the following examples, the wastewater treatment was carried out according to the scheme shown in FIG. 1.
Comparative example 1
The processing object is as follows: can be used for treating leather wastewater of leather factories. The wastewater is characterized as follows: average COD is 1000mg/L, ammonia nitrogen concentration is 800-1000 mg/L, total nitrogen concentration is 1000-1500mg/L, suspended matter is 1000-1500mg/L, and pH value is 8-10.
Biochemical system anoxic tank 800m3Aerobic tank 1500m3Daily treated water amount 800m3/d。
The treatment process is as follows:
s1, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S2, enabling the pretreated effluent to enter an anoxic tank, wherein the anoxic tank is stirred without equipment, the operation conditions control the dissolved oxygen to be 0.4-0.6mg/L, the pH value to be 6.5-7.5, the hydraulic retention time is 22-26h, and no carbon source is added into the whole anoxic tank;
s3, the effluent of the anoxic tank enters an aerobic tank, and the operating conditions of the aerobic tank are as follows: 4-6mg/L of dissolved oxygen, 28-30 ℃, 5.5-7.0 of pH value, 45-48h of hydraulic retention time and no return of nitrified liquid.
And S4, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom for 20 hours.
The treatment effect is as follows: the total nitrogen is more than 300mg/L, the ammonia nitrogen is more than 200mg/L, and the COD is more than 200 mg/L. Does not meet the execution standard GB 30486-2013 discharge standard of water pollutants for leather and fur processing industry-ammonia nitrogen is less than or equal to 70mg/L, COD is less than or equal to 300mg/L, and total nitrogen is less than or equal to 140 mg/L.
Example 1
The processing object is as follows: as in comparative example 1.
Upgrading operation is carried out on the basis of the primary localization system of the comparative example 1, and the specific steps are as follows:
s1, adding 30% of polyurethane foam biological filler into an anoxic tank and an aerobic tank of the primary biochemical system. The aerobic tank is treated as follows: adjusting an aeration system of the aerobic tank, and controlling the dissolved oxygen of the aerobic tank to be 0.5 mg/L; adding sodium carbonate, and maintaining the pH value to be 7.0; the water inflow of the system is adjusted, and the hydraulic retention time is controlled to be 24 h. Until the ammonia nitrogen degradation rate of the aerobic tank is 400mg/L.d and the accumulation rate of the effluent nitrite nitrogen is more than or equal to 80 percent, the shortcut nitrification bacteria are considered to be dominant bacteria in the activated sludge of the aerobic tank of the system, the shortcut nitrification process is started and the system can be operated by water inflow.
S2, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S3, feeding the pretreated effluent into an anoxic tank, and adding the carbon source according to the C/N ratio of 2.5. The feeding mode is intermittent feeding, and specifically comprises the following steps: 60 wt% of the total amount of the carbon source is added in the first 6h, 30 wt% of the total amount of the carbon source is added after 2h interval, and the rest 10 wt% is added after 1h interval.
The operating conditions of the anoxic pond are as follows: the dissolved oxygen is 0.1mg/L, the pH value is 7.0, and the hydraulic retention time is 14 h.
And S4, the effluent of the anoxic tank enters an aerobic tank.
The operating conditions of the aerobic tank are as follows: the dissolved oxygen is 0.5mg/L, the temperature is 25 ℃, the pH value is 7.0, the hydraulic retention time is 37h, and the reflux ratio is 120%.
And S5, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom for 9 hours.
S6, the effluent of the secondary sedimentation tank enters an aeration biological filter, the filler is volcanic rock, and the adding amount accounts for 40% of the volume of the tank body.
The operating conditions of the biological aerated filter are as follows: 4mg/L of dissolved oxygen, 6.5 of pH and 50 h/time of backwashing frequency. And (4) treating the wastewater by using the biological aerated filter to obtain treated wastewater.
In the operation process, the secondary sedimentation tank needs to regularly discharge the sludge to prevent the sludge from being discharged due to overhigh sludge surface, and the sludge discharge amount is controlled to make the SV30 of the aerobic tank be 20%.
Example 2
The processing object and the processing process are the same as in example 1, except that the individual process parameters are adjusted as follows:
s1, adding 30% polyurethane foam into the anoxic tank and the aerobic tank of the primary biochemical system. The aerobic tank is treated as follows: adjusting an aeration system of the aerobic tank, and controlling the dissolved oxygen of the aerobic tank to be 1 mg/L; adding sodium carbonate, and maintaining the pH value to be 7.5; the water inflow of the system is adjusted, and the hydraulic retention time is controlled to be 36 h. Until the ammonia nitrogen degradation rate of the aerobic tank is 500mg/L.d and the accumulation rate of the effluent nitrite nitrogen is more than or equal to 80 percent, the shortcut nitrification is started and the operation is normal.
S2, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S3, feeding the pretreated effluent into an anoxic tank, and adding the carbon source according to the C/N ratio of 3.0. The feeding mode is intermittent feeding, and specifically comprises the following steps: 60 wt% of the total amount of the carbon source is added in the first 6h, 30 wt% of the total amount of the carbon source is added after 2h interval, and the rest 10 wt% is added after 1h interval.
The operating conditions of the anoxic pond are as follows: the dissolved oxygen is 0.2mg/L, the pH value is 7.5, and the hydraulic retention time is 19 h.
And S4, the effluent of the anoxic tank enters an aerobic tank.
The operating conditions of the aerobic tank are as follows: the dissolved oxygen is 1.5mg/L, the temperature is 30 ℃, the pH value is 7.5, the hydraulic retention time is 24h, and the reflux ratio is 150%.
And S5, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom, wherein the retention time is 10 hours.
S6, the effluent of the secondary sedimentation tank enters an aeration biological filter tank, the filler is volcanic rock, and the adding amount accounts for 45% of the volume of the tank body.
The operating conditions of the biological aerated filter are as follows: dissolved oxygen of 7mg/L, pH 7.5 and backwashing frequency of 40 h/time. And (4) treating the wastewater by using the biological aerated filter to obtain treated wastewater.
In the operation process, the secondary sedimentation tank needs to regularly discharge the sludge to prevent the sludge from being discharged due to overhigh sludge surface, and the sludge discharge amount is controlled to enable the SV30 of the aerobic tank to be 25%.
Example 3
The processing object and the processing process are the same as in example 1, except that the individual process parameters are adjusted as follows:
s1, adding 30% polyurethane foam into the anoxic tank and the aerobic tank of the primary biochemical system. The aerobic tank is treated as follows: adjusting an aeration system of the aerobic tank, and controlling the dissolved oxygen of the aerobic tank to be 2 mg/L; adding sodium carbonate, and maintaining the pH value at 8.0; the water inflow of the system is adjusted, and the hydraulic retention time is controlled to be 48 h. Until the ammonia nitrogen degradation rate of the aerobic tank is 600mg/L.d and the accumulation rate of the effluent nitrite nitrogen is more than or equal to 80 percent, the shortcut nitrification is started and the operation is normal.
S2, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S3, feeding the pretreated effluent into an anoxic tank, and adding the carbon source according to the C/N ratio of 3.5. The feeding mode is intermittent feeding, and specifically comprises the following steps: 60 wt% of the total amount of the carbon source is added in the first 6h, 30 wt% of the total amount of the carbon source is added after 2h interval, and the rest 10 wt% is added after 1h interval.
The operating conditions of the anoxic pond are as follows: the dissolved oxygen is 0.3mg/L, the pH value is 8.0, and the hydraulic retention time is 18 h.
And S4, the effluent of the anoxic tank enters an aerobic tank.
The operating conditions of the aerobic tank are as follows: the dissolved oxygen is 3mg/L, the temperature is 35 ℃, the pH value is 8.0, the hydraulic retention time is 34h, and the reflux ratio is 180 percent.
And S5, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom, wherein the retention time is 10 hours.
S6, the effluent of the secondary sedimentation tank enters an aeration biological filter, the filler is volcanic rock, and the adding amount accounts for 50% of the volume of the tank body.
The operating conditions of the biological aerated filter are as follows: dissolved oxygen of 10mg/L, pH of 8.5 and backwashing frequency of 45 h/time. And (4) treating the wastewater by using the biological aerated filter to obtain treated wastewater.
In the operation process, the secondary sedimentation tank needs to regularly discharge the sludge to prevent the sludge from being discharged due to overhigh sludge surface, and the sludge discharge amount is controlled to ensure that the SV30 of the aerobic tank is 30 percent.
Example 4
After 2 months of operation according to comparative example 1 and examples 1-3, respectively, the operation effect was tested and the results are shown in table 1.
TABLE 1 operational Effect of comparative example 1 and examples 1-3
Note: in Table 1, the daily treatment load increase rate, the carbon source consumption amount decrease rate and the power consumption amount decrease rate in examples 1 to 3 are the change rates obtained as compared with comparative example 1.
As can be seen from the test results in Table 1, compared with the original treatment method, the treatment method provided by the invention can effectively improve the treatment effect, so that the effluent COD, ammonia nitrogen and total nitrogen of the discharged water all reach the discharge standard of pollutants in water in the leather and fur processing industry GB 30486-2013; the nitrite state accumulation rate reaches more than 80 percent. Meanwhile, the treatment method disclosed by the invention does not need to additionally add an alkalinity agent, the consumption of the carbon source and the power consumption are obviously reduced, the daily treatment load of the system is obviously improved, and the high-efficiency, low-cost and low-energy-consumption treatment of the high-total-nitrogen leather wastewater is realized.
Comparative example 2
The processing object is as follows: leather wastewater of certain leather factories in Hebei. The wastewater is characterized as follows: the average COD is 1500mg/L, the ammonia nitrogen concentration is 600-800 mg/L, the total nitrogen concentration is 800-1000 mg/L, the suspended matter is 1200-1500mg/L, and the pH value is 10-12.
Biochemical system anoxic tank 600m3Aerobic tank 1200m3Daily treated water amount 700m3/d。
The treatment process is as follows:
s1, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S2, feeding the pretreated effluent into an anoxic tank, stirring the anoxic tank in an aeration mode, controlling the dissolved oxygen by 0.3-0.5mg/L, controlling the pH value to be 6.0-7.5 under the operation condition, and keeping the hydraulic retention time for 20-22h, wherein no carbon source is added into the whole anoxic tank;
s3, the effluent of the anoxic tank enters an aerobic tank, and the operating conditions of the aerobic tank are as follows: 4-6mg/L of dissolved oxygen, 28-30 ℃, 6.0-7.0 of pH value, 38-41h of hydraulic retention time and no return of nitrified liquid.
And S4, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom, wherein the retention time is 15 hours.
The treatment effect is as follows: the total nitrogen is more than 200mg/L, the ammonia nitrogen is more than 100mg/L, and the COD is more than 400mg/L. Does not meet the execution standard GB 30486-2013 discharge standard of water pollutants for leather and fur processing industry-ammonia nitrogen is less than or equal to 70mg/L, COD is less than or equal to 300mg/L, and total nitrogen is less than or equal to 140 mg/L.
Example 5
The processing object is as follows: as in comparative example 2.
The upgrading operation is carried out on the basis of the primary localization system of the comparative example 2, which comprises the following specific steps:
s1, adding 30% polyurethane foam into the anoxic tank and the aerobic tank of the primary biochemical system. The aerobic tank is treated as follows: adjusting an aeration system of the aerobic tank, and controlling the dissolved oxygen of the aerobic tank to be 1.5 mg/L; adding sodium carbonate, and maintaining the pH value to be 7.5; the water inflow of the system is adjusted, and the hydraulic retention time is controlled to be 24 h. Until the ammonia nitrogen degradation rate of the aerobic tank is 400mg/L.d and the accumulation rate of the effluent nitrite nitrogen is more than or equal to 80 percent, the shortcut nitrification is started and the operation is normal.
S2, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S3, feeding the pretreated effluent into an anoxic tank, and adding the carbon source according to the C/N ratio of 3.0. The feeding mode is intermittent feeding, and specifically comprises the following steps: 60 wt% of the total amount of the carbon source is added in the first 12h, 30 wt% of the total amount of the carbon source is added after 4h, and the rest 10 wt% is added after 2 h.
The operating conditions of the anoxic pond are as follows: the dissolved oxygen is 0.2mg/L, the pH value is 7.5, and the hydraulic retention time is 14 h.
And S4, the effluent of the anoxic tank enters an aerobic tank.
The operating conditions of the aerobic tank are as follows: the dissolved oxygen is 1.5mg/L, the temperature is 25 ℃, the pH value is 7.0, the hydraulic retention time is 28h, and the reflux ratio is 180 percent.
And S5, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom, wherein the retention time is 15 hours.
S6, the effluent of the secondary sedimentation tank enters an aeration biological filter, the filler is volcanic rock, and the adding amount accounts for 40% of the volume of the tank body.
The operating conditions of the biological aerated filter are as follows: 4mg/L of dissolved oxygen, 6.5 of pH and 50 h/time of backwashing frequency. And (4) treating the wastewater by using the biological aerated filter to obtain treated wastewater.
In the operation process, the secondary sedimentation tank needs to regularly discharge the sludge to prevent the sludge from being discharged due to overhigh sludge surface, and the sludge discharge amount is controlled to make the SV30 of the aerobic tank be 20%.
Example 6
The processing object and the processing procedure are the same as those in example 5, except that the individual process parameters are adjusted as follows:
s1, adding 30% polyurethane foam into the anoxic tank and the aerobic tank of the primary biochemical system. The aerobic tank is treated as follows: adjusting an aeration system of the aerobic tank, and controlling the dissolved oxygen of the aerobic tank to be 2.5 mg/L; adding sodium carbonate, and maintaining the pH value at 8.5; the water inflow of the system is adjusted, and the hydraulic retention time is controlled to be 48 h. Until the ammonia nitrogen degradation rate of the aerobic tank is 500mg/L.d and the accumulation rate of the effluent nitrite nitrogen is more than or equal to 80 percent, the shortcut nitrification is started and the operation is normal.
S2, the wastewater firstly enters a primary sedimentation tank, after large-particle substances such as animal fur and the like and a part of suspended matters are removed, the supernatant is used as pretreated effluent and enters the next flow.
S3, feeding the pretreated effluent into an anoxic tank, and adding the carbon source according to the C/N ratio of 3.5. The feeding mode is intermittent feeding, and specifically comprises the following steps: 60 wt% of the total amount of the carbon source is added in the first 12h, 30 wt% of the total amount of the carbon source is added after 4h, and the rest 10 wt% is added after 2 h.
The operating conditions of the anoxic pond are as follows: the dissolved oxygen is 0.3mg/L, the pH value is 8.5, and the hydraulic retention time is 16 h.
And S4, the effluent of the anoxic tank enters an aerobic tank.
The operating conditions of the aerobic tank are as follows: the dissolved oxygen is 2.5mg/L, the temperature is 35 ℃, the pH value is 8.5, the hydraulic retention time is 33h, and the reflux ratio is 250%.
And S5, allowing the effluent of the aerobic tank to enter a secondary sedimentation tank, and settling and separating sludge until the sludge is settled to the bottom for 20 hours.
S6, the effluent of the secondary sedimentation tank enters an aeration biological filter, the filler is volcanic rock, and the adding amount accounts for 60% of the volume of the tank body.
The operating conditions of the biological aerated filter are as follows: dissolved oxygen of 10mg/L, pH of 8.5 and backwashing frequency of 45 h/time. And (4) treating the wastewater by using the biological aerated filter to obtain treated wastewater.
In the operation process, the secondary sedimentation tank needs to regularly discharge the sludge to prevent the sludge from being discharged due to overhigh sludge surface, and the sludge discharge amount is controlled to ensure that the SV30 of the aerobic tank is 30 percent.
Example 7
After 2 months of operation according to comparative example 2 and examples 5-6, respectively, the operation effect was tested and the results are shown in table 2.
TABLE 2 run effects of comparative example 2 and examples 5-6
Note: in Table 2, in examples 5 to 6, the daily treatment load increase rate, the carbon source consumption amount decrease rate and the power consumption amount decrease rate were the change rates obtained as compared with comparative example 2.
As can be seen from the test results in Table 2, compared with the original treatment method, the treatment method provided by the invention can effectively improve the treatment effect, so that the effluent COD, ammonia nitrogen and total nitrogen of the discharged water all reach the discharge standard of pollutants in water in the leather and fur processing industry GB 30486-2013; the nitrite state accumulation rate reaches more than 85 percent. Meanwhile, the treatment method disclosed by the invention does not need to additionally add an alkalinity agent, the consumption of the carbon source and the power consumption are obviously reduced, the daily treatment load of the system is obviously improved, and the high-efficiency, low-cost and low-energy-consumption treatment of the high-total-nitrogen leather wastewater is realized.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A method for treating leather wastewater with high total nitrogen content is characterized by comprising the following steps:
controlling the aerobic tank condition to start short-cut nitrification until the short-cut nitrification is mature, and sequentially carrying out anoxic tank treatment, aerobic tank treatment, secondary sedimentation tank treatment and biological filter tank treatment on the leather wastewater to obtain treated wastewater;
the conditions of the aerobic tank for starting the short-cut nitrification are as follows: the dissolved oxygen is 1.0-2.5 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 12-48 h;
the operating conditions of the aerobic tank treatment are as follows: the dissolved oxygen is 0.5-3 mg/L, the temperature is 25-35 ℃, the pH value is 7.0-8.5, and the hydraulic retention time is 12-48 h;
the adding amount of an external carbon source in the anoxic pond treatment is controlled to enable the C/N ratio of the anoxic pond to be 2.5-3.5;
biological fillers are added in the anoxic tank and the aerobic tank.
2. The treatment method according to claim 1, wherein the indexes of shortcut nitrification maturation are as follows: the degradation rate of ammonia nitrogen is 200-600 mg/L.d, and the accumulation rate of nitrite nitrogen in the effluent of the aerobic tank is more than or equal to 80%.
3. The process of claim 1, wherein the anoxic tank process is operated under the following conditions: the dissolved oxygen is 0.1-0.3 mg/L, the pH value is 7.0-8.0, and the hydraulic retention time is 14-28 h.
4. The treatment method as claimed in claim 1, wherein the reflux ratio of the aerobic tank treatment is 100-300%.
5. The treatment method according to claim 1, wherein the biological filler is a polyurethane foam;
the total nitrogen content of the leather wastewater is 800-1500 mg/L, and the COD is 800-1500 mg/L.
6. The treatment process according to claim 1 or 5, characterized in that the biological filler is added in an amount such that: the volume of the biological filler accounts for 30 percent of the volume of the tank body.
7. The process of claim 1, wherein the carbon source is added in a batch-wise fed-batch manner;
the intermittent feeding comprises the following specific operations: 60 wt% of the total amount of the carbon source is added in the first 6-12 h, 30 wt% of the total amount of the carbon source is added after 2-4 h intervals, and the rest 10 wt% is added after 1-2 h intervals.
8. The treatment method according to claim 1, wherein the residence time of the secondary sedimentation tank treatment is 9-20 h.
9. The process of claim 1, wherein the filler in the biofilter is volcanic rock;
the volume of the volcanic rock accounts for 40-60% of the volume of the tank body;
the conditions of the biological filter tank treatment are as follows: 4-10 mg/L of dissolved oxygen, 6.5-8.5 of pH and 36-72 h/time of backwashing frequency.
10. The treatment method as claimed in claim 1, wherein periodic sludge discharge is carried out during the treatment of the leather wastewater, and the sludge SV30 of the aerobic pool is controlled to be 20-30%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010123749.0A CN111320323A (en) | 2020-02-27 | 2020-02-27 | Treatment method of high-total-nitrogen leather wastewater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010123749.0A CN111320323A (en) | 2020-02-27 | 2020-02-27 | Treatment method of high-total-nitrogen leather wastewater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111320323A true CN111320323A (en) | 2020-06-23 |
Family
ID=71165323
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010123749.0A Pending CN111320323A (en) | 2020-02-27 | 2020-02-27 | Treatment method of high-total-nitrogen leather wastewater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111320323A (en) |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101941782A (en) * | 2010-09-27 | 2011-01-12 | 福建微水环保技术有限公司 | Method for treating leather wastewater |
| CN101973678A (en) * | 2010-11-03 | 2011-02-16 | 上海泓济环保工程有限公司 | Bioaugmentation treatment technology of high ammonia nitrogen wastewater |
| CN102583747A (en) * | 2012-03-20 | 2012-07-18 | 哈尔滨工业大学 | Device and process for biochemically denitrifying high-ammonia nitrogen tanning wastewater |
| CN102718371A (en) * | 2012-07-13 | 2012-10-10 | 神华集团有限责任公司 | Treatment method and treatment equipment for coal chemical industry wastewater |
| CN103373760A (en) * | 2012-04-29 | 2013-10-30 | 中国石油化工股份有限公司 | Quick start method for treating ammonia-containing wastewater by A/O process |
| CN103449659A (en) * | 2013-07-23 | 2013-12-18 | 宁波清天地环境工程有限公司 | Novel partial nitrification-denitrification biological nitrogen removal device |
| CN104129890A (en) * | 2014-07-29 | 2014-11-05 | 湖南艾布鲁环保科技有限公司 | Device and method for enhanced biochemical process for advanced treatment of high ammonia nitrogen industrial wastewater |
| CN104710087A (en) * | 2015-04-07 | 2015-06-17 | 山东省环境保护科学研究设计院 | Hypoxia-aerobic comprehensive treatment method for tannery waste water |
| CN105384247A (en) * | 2015-10-31 | 2016-03-09 | 北京工业大学 | Method for oxidizing and denitrifying part of denitrification coupled anaerobic ammonia through A/O biological membrane process |
| WO2018101892A1 (en) * | 2016-11-29 | 2018-06-07 | Hasan Kalyoncu Universitesi | Advanced biological treatment method for slaughterhouses wastewater |
| CN108996687A (en) * | 2018-07-27 | 2018-12-14 | 济南大学 | A kind of short distance backflow intensifying anoxic/aerobic reactor nitrogen rejection facility and method |
| CN110668641A (en) * | 2019-10-15 | 2020-01-10 | 山东海景天环保科技股份公司 | Method for treating high-salinity high-total-nitrogen tanning wastewater based on low C/N |
| CN110683646A (en) * | 2019-11-04 | 2020-01-14 | 黄河三角洲京博化工研究院有限公司 | Process for rapidly realizing short-cut nitrification and denitrification of leather wastewater |
-
2020
- 2020-02-27 CN CN202010123749.0A patent/CN111320323A/en active Pending
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101941782A (en) * | 2010-09-27 | 2011-01-12 | 福建微水环保技术有限公司 | Method for treating leather wastewater |
| CN101973678A (en) * | 2010-11-03 | 2011-02-16 | 上海泓济环保工程有限公司 | Bioaugmentation treatment technology of high ammonia nitrogen wastewater |
| CN102583747A (en) * | 2012-03-20 | 2012-07-18 | 哈尔滨工业大学 | Device and process for biochemically denitrifying high-ammonia nitrogen tanning wastewater |
| CN103373760A (en) * | 2012-04-29 | 2013-10-30 | 中国石油化工股份有限公司 | Quick start method for treating ammonia-containing wastewater by A/O process |
| CN102718371A (en) * | 2012-07-13 | 2012-10-10 | 神华集团有限责任公司 | Treatment method and treatment equipment for coal chemical industry wastewater |
| CN103449659A (en) * | 2013-07-23 | 2013-12-18 | 宁波清天地环境工程有限公司 | Novel partial nitrification-denitrification biological nitrogen removal device |
| CN104129890A (en) * | 2014-07-29 | 2014-11-05 | 湖南艾布鲁环保科技有限公司 | Device and method for enhanced biochemical process for advanced treatment of high ammonia nitrogen industrial wastewater |
| CN104710087A (en) * | 2015-04-07 | 2015-06-17 | 山东省环境保护科学研究设计院 | Hypoxia-aerobic comprehensive treatment method for tannery waste water |
| CN105384247A (en) * | 2015-10-31 | 2016-03-09 | 北京工业大学 | Method for oxidizing and denitrifying part of denitrification coupled anaerobic ammonia through A/O biological membrane process |
| WO2018101892A1 (en) * | 2016-11-29 | 2018-06-07 | Hasan Kalyoncu Universitesi | Advanced biological treatment method for slaughterhouses wastewater |
| CN108996687A (en) * | 2018-07-27 | 2018-12-14 | 济南大学 | A kind of short distance backflow intensifying anoxic/aerobic reactor nitrogen rejection facility and method |
| CN110668641A (en) * | 2019-10-15 | 2020-01-10 | 山东海景天环保科技股份公司 | Method for treating high-salinity high-total-nitrogen tanning wastewater based on low C/N |
| CN110683646A (en) * | 2019-11-04 | 2020-01-14 | 黄河三角洲京博化工研究院有限公司 | Process for rapidly realizing short-cut nitrification and denitrification of leather wastewater |
Non-Patent Citations (7)
| Title |
|---|
| XIAOLIAN WANG ET.AL: ""Short-cut nitrification of domestic wastewater in a pilot-scale A/O nitrogen removal plant"", 《BIOPROCESS AND BIOSYSTEMS ENGINEERING》 * |
| 吕凌云等: ""制革废水中氨氮脱除方法的研究进展"", 《西部皮革》 * |
| 吴军等: "《村镇生活污水处理技术及管理维护》", 30 May 2019, 冶金工业出版社 * |
| 宋庆祥等: ""去除制革废水氨氮的工艺改造"", 《工业用水与废水》 * |
| 毛玉红编著: "《水生物处理新技术》", 30 April 2015, 中国铁道出版社 * |
| 熊江磊: "《自生动态生物膜技术》", 28 February 2015, 东南大学出版社 * |
| 陈学群等: ""制革废水脱氮技术浅析"", 《西部皮革》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108483655B (en) | A method for deep denitrification of short-range nitrification and denitrification coupled with anaerobic ammonia oxidation and sulfur autotrophic denitrification | |
| CN106865773B (en) | Device and method for realizing partial shortcut nitrification-anaerobic ammonia oxidation by adding hydroxylamine | |
| CN113415910B (en) | A device and method for short-range denitrification coupling anaerobic ammonium oxidation biological nitrogen and phosphorus removal in iron ammonium oxidation enhanced AAO process | |
| CN104710087B (en) | Hypoxia-aerobic comprehensive treatment method for tannery waste water | |
| CN110510739B (en) | Device and method for realizing semi-short-range coupling anaerobic ammonia oxidation of continuous flow AOA (argon oxygen decarburization) biomembrane through hydroxylamine | |
| CN113200600B (en) | Device and method for treating high-ammonia-nitrogen organic matter wastewater by semi-shortcut nitrification anaerobic ammonia oxidation and serial shortcut denitrification anaerobic ammonia oxidation | |
| CN102040315A (en) | Method for treating high ammonia nitrogen wastewater by two-stage A/O process | |
| CN111039500A (en) | Short-range and full-range coupled biological denitrification process for treating electroplating wastewater | |
| CN112299559A (en) | Whole-process nitrification, short-process denitrification and anaerobic ammonia oxidation single-stage coupling process control method | |
| CN113023872A (en) | Device and method for realizing domestic sewage denitrification by synchronous shortcut nitrification-denitrification-anaerobic ammonia oxidation coupling denitrification | |
| CN101456626A (en) | A<2>/O oxidation ditch process operation control method | |
| CN111392865A (en) | Method for treating organic amine wastewater | |
| Bernat et al. | The treatment of anaerobic digester supernatant by combined partial ammonium oxidation and denitrification | |
| CN105800873A (en) | Method for treating high-concentration ammonia nitrogen wastewater by autotrophic denitrification process | |
| EP1630139A1 (en) | Process for the biological denitrification of ammonium containing wastewater | |
| CN113511731A (en) | Method for improving nitrite accumulation in short-range denitrification process | |
| CN110723817B (en) | Short-cut nitrification-anaerobic ammonia oxidation process for efficiently treating low-carbon high-ammonia-nitrogen wastewater | |
| JP3656426B2 (en) | Biological treatment of ammoniacal nitrogen | |
| CN109354174B (en) | CANON _ MBBR-based rapid starting method of enhanced denitrification system | |
| CN111115983A (en) | CANON-MBBR system without excessive accumulation of nitrous oxides and operation method | |
| CN217535756U (en) | Emulsion explosive waste water processing system | |
| CN111320323A (en) | Treatment method of high-total-nitrogen leather wastewater | |
| CN112408699B (en) | An integrated method for denitrification of waste water containing toxic organic matter | |
| CN211644995U (en) | Non-nitrous excessive accumulation CANON-MBBR system | |
| CN114477456A (en) | Endogenous short-cut denitrification enhanced municipal sewage short-cut nitrification/anaerobic ammonia oxidation deep denitrification device and method |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200623 |