Recovery method of high-ammonia-nitrogen organic wastewater

Abstract

The invention discloses a method for recovering high-ammonia-nitrogen organic wastewater, which comprises the following steps of: a, feeding the high-ammonia-nitrogen organic wastewater into an anaerobic bioreactor for anaerobic digestion treatment to obtain methane and high-ammonia-nitrogen wastewater; b, respectively feeding the high-ammonia-nitrogen wastewater and the draw solution into a raw material liquid side and a draw solution side of a forward osmosis membrane assembly, and carrying out forward osmosis treatment; c, feeding the effluent on the draw liquid side after the forward osmosis treatment into a nanofiltration membrane assembly, and carrying out nanofiltration treatment to obtain first produced water; d, feeding the high-ammonia-nitrogen wastewater subjected to forward osmosis treatment and concentrated on the raw material liquid side into a short-cut nitrification / anaerobic ammonia oxidation reactor, and carrying out short-cut nitrification and anaerobic ammonia oxidation treatment; and e, feeding the effluent after anaerobic ammonia oxidation treatment and methane generated in the step a into a methane denitrification reactor, and carrying out denitrification treatment to obtain second produced water. According to the method disclosed by the invention, organic matters in the high-ammonia-nitrogen organic wastewater can be efficiently recovered and utilized, ammonia nitrogen is removed, and high-quality produced water is obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment, and in particular relates to a method for recovering high-ammonia nitrogen organic wastewater. Background Art

[0002] Ammonia nitrogen wastewater mainly comes from fertilizers, coking, petrochemicals, pharmaceuticals, food, landfills, etc. A large amount of ammonia nitrogen wastewater discharged into water bodies will not only cause eutrophication of water bodies and make the water bodies black and smelly, but also increase the difficulty and cost of water treatment, and even have toxic effects on people and organisms.

[0003] The treatment processes for ammonia nitrogen wastewater mainly include biological methods, physical and chemical methods and other treatment processes. Due to the complex water quality and high pollutant concentration of high ammonia nitrogen organic wastewater, a single process link is difficult to meet the water quality requirements. At present, the treatment of high-concentration ammonia nitrogen organic wastewater mostly requires multiple links such as pretreatment, anaerobic treatment, aerobic treatment and deep treatment. The process settings are complex, the cost is high, the ammonia nitrogen treatment is difficult, and the total nitrogen in the effluent is difficult to remove deeply. Therefore, it is necessary to conduct in-depth research to develop a process that can efficiently treat high-concentration ammonia nitrogen organic wastewater. Summary of the invention

[0004] The present invention is based on the inventor's discovery and understanding of the following facts and problems: the current treatment process for high-concentration ammonia nitrogen wastewater has the problems of complex process, high cost and poor effluent quality, and further research and improvement are needed.

[0005] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, an embodiment of the present invention proposes a method for recovering high-ammonia nitrogen organic wastewater, which uses anaerobic digestion to achieve methanation of organic matter, concentrates the high-ammonia nitrogen wastewater through a forward osmosis-nanofiltration process and produces a high-quality water product, and at the same time, the concentrated high-ammonia nitrogen wastewater is treated by short-range nitrification / anaerobic ammonia oxidation under low-carbon source conditions and uses methane gas produced by anaerobic digestion as a carbon source to achieve deep denitrification and nitrogen removal, and obtain another high-quality water product, which solves the problem of difficult removal of total nitrogen in deep treatment while collecting organic matter to the greatest extent, and realizes efficient recovery of water resources and improves the water quality of produced water.

[0006] The method for recovering high-ammonia nitrogen organic wastewater according to the embodiment of the present invention comprises:

[0007] a. Sending high-ammonia nitrogen organic wastewater into an anaerobic bioreactor for anaerobic digestion treatment to obtain methane and high-ammonia nitrogen wastewater;

[0008] b. The high ammonia nitrogen wastewater and the draw liquid obtained in step a are respectively fed to the raw liquid side and the draw liquid side of the forward osmosis membrane module for forward osmosis treatment;

[0009] c. sending the effluent from the draw liquid side after forward osmosis treatment in step b to a nanofiltration membrane assembly to obtain the first produced water after nanofiltration treatment;

[0010] d. The concentrated high-ammonia nitrogen wastewater from the raw material liquid side after forward osmosis treatment in step b is sent to a short-cut nitrification / anaerobic ammonium oxidation reactor for short-cut nitrification and anaerobic ammonium oxidation treatment;

[0011] e. The effluent after the anaerobic ammonium oxidation treatment in step d and the methane produced in step a are sent to a methane denitrification reactor for denitrification treatment to obtain a second produced water.

[0012] Advantages and technical effects of the method for recovering high-ammonia nitrogen organic wastewater according to the embodiment of the present invention:

[0013] In the method of the embodiment of the present invention, high-concentration ammonia nitrogen organic wastewater is first subjected to anaerobic digestion treatment to achieve the removal of organic matter, and a part of the generated methane is sent to the subsequent methane denitrification reactor as a carbon source for denitrification, and the other part can be used as fuel for energy recovery; the high-ammonia nitrogen wastewater with organic matter removed produced by anaerobic digestion treatment is subjected to forward osmosis treatment using a forward osmosis membrane assembly under the action of an extraction liquid, and the diluted extraction liquid is subjected to nanofiltration treatment to obtain a high-quality first-pass produced water, so that water resources are recovered, and the high-ammonia nitrogen wastewater concentrated by forward osmosis is subjected to short-cut nitrification in a short-cut nitrification / anaerobic ammonia oxidation reactor, and part of the ammonia nitrogen in the high-ammonia nitrogen wastewater is subjected to short-cut nitrification to generate Nitrite nitrogen, the generated nitrite nitrogen and the remaining ammonia nitrogen in the high-ammonia nitrogen wastewater are treated by anaerobic ammonia oxidation to generate nitrogen and nitric nitrogen; the effluent from the short-cut nitrification / anaerobic ammonia oxidation reactor enters the methane denitrification reactor for denitrification treatment, and the methane generated by anaerobic digestion treatment is used as the carbon source required for denitrification to remove nitrate nitrogen in the effluent from the short-cut nitrification / anaerobic ammonia oxidation reactor, thereby obtaining a second high-quality effluent. After the recovery treatment of the method of the present invention, energy recovery and efficient utilization of organic matter in high-ammonia nitrogen organic wastewater are achieved, while high-concentration ammonia nitrogen in the wastewater is efficiently removed, and two high-quality produced water is obtained, thereby achieving efficient recovery of water resources and improving the quality of produced water.

[0014] In some embodiments, in step a, the high-ammonia nitrogen organic wastewater is sent to an anaerobic bioreactor after removing floating matter and / or suspended matter through a grid well.

[0015] In some embodiments, in step a, the anaerobic bioreactor includes one of a completely mixed anaerobic reactor (CSTR), an upflow anaerobic sludge blanket reactor (UASB), an expanded granular sludge blanket (EGSB), and an anaerobic baffled reactor (ABR).

[0016] In some embodiments, in step a, the obtained methane is recovered by a gas recovery device and then partially sent to a fuel recovery system, and the other part is sent to the methane denitrification reactor in step e.

[0017] In some embodiments, in step b, the draw liquid includes at least one of sodium chloride, sodium sulfate, disodium ethylenediaminetetraacetate or a scale inhibitor. Preferably, the scale inhibitor includes at least one of diethylenetriaminepenta(methylenephosphonic acid)heptasodium, hydrolyzed polymaleic anhydride, sodium polyaspartate, 2-acrylamide-2-methylpropanesulfonic acid, aminotri(methylenesulfonic acid)sulfuric acid, sodium hydroxyethylidene diphosphonate, polyepoxysuccinic acid, 2-phospho-1,2,4-tricarboxylic acid butane, sodium polymethacrylate and sodium molybdate; preferably, the concentration of the draw liquid is 30 to 500 g / L, preferably 100 to 400 g / L; further preferably, the concentration of sodium chloride is not less than 30 g / L; sulfuric acid The concentration of sodium shall not be less than 40g / L; the concentration of diethylenetriamine pentasodium methylenephosphonate shall not be less than 51g / L; the concentration of sodium polyaspartate shall not be less than 93g / L; the concentration of sodium molybdate shall not be less than 89g / L; the concentration of sodium hydroxyethylidene diphosphonate shall not be less than 105g / L; the concentration of polyepoxysuccinic acid shall not be less than 113g / L; the concentration of 2-phospho-1,2,4-tricarboxylic acid butane shall not be less than 141g / L; the concentration of aminotrimethylene sulfate shall not be less than 165g / L; the concentration of sodium polymethacrylate shall not be less than 198g / L; the concentration of hydrolyzed polymaleic anhydride shall not be less than 252g / L; and the concentration of 2-acrylamide-2-methylpropanesulfonic acid shall not be less than 269g / L.

[0018] In some embodiments, in step b, the forward osmosis membrane assembly includes an active layer and a support layer, the active layer includes cellulose triacetate, and the support layer includes polyester fiber, wherein the active layer faces the high ammonia nitrogen wastewater side.

[0019] In some embodiments, in step d, the short-cut nitrification / anaerobic ammonium oxidation reactor comprises one of a continuous flow reactor (CSTR), a sequencing batch reactor (SBR), a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor (UASB).

[0020] In some embodiments, in step d, the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor is aerated to control the dissolved oxygen in the lower part of the reactor to 0.2-0.4 mg / L, and the upper part of the reactor is in an anaerobic state.

[0021] In some embodiments, in step e, the methane denitrification reactor includes one of an upflow anaerobic sludge blanket reactor (UASB), an anaerobic baffled reactor (ABR), a completely mixed anaerobic reactor (CSTR), and an internal circulation anaerobic reactor (IC).

[0022] The embodiment of the present invention also provides a high-ammonia nitrogen organic wastewater recovery device, including an anaerobic bioreactor, a forward osmosis membrane assembly, a nanofiltration membrane assembly, a short-range nitrification / anaerobic ammonium oxidation reactor and a methane denitrification reactor, wherein:

[0023] The water outlet of the anaerobic bioreactor is connected to the water inlet on the raw liquid side of the forward osmosis membrane assembly, and the methane gas outlet of the anaerobic bioreactor is connected to the gas inlet of the gas recovery device;

[0024] The water outlet on the draw liquid side of the forward osmosis membrane assembly is connected to the water inlet on the concentrated water side of the nanofiltration membrane assembly, and the water outlet on the raw liquid side of the forward osmosis membrane assembly is connected to the bottom water inlet of the short-range nitrification / anaerobic ammonium oxidation reactor;

[0025] The water outlet of the short-cut nitrification / anaerobic ammonium oxidation reactor is connected to the water inlet of the methane denitrification reactor;

[0026] The gas inlet of the methane denitrification reactor is connected to the gas outlet of the gas recovery device.

[0027] The high-ammonia nitrogen organic wastewater recovery device of the embodiment of the present invention can remove organic matter from high-concentration ammonia nitrogen organic wastewater in an anaerobic bioreactor, and the generated methane is sent to a methane denitrification reactor as a carbon source for denitrification. The high-ammonia nitrogen wastewater with organic matter removed is concentrated under the action of the draw liquid by using a forward osmosis membrane assembly. The diluted draw liquid is treated in a nanofiltration membrane assembly to obtain a high-quality first-pass water product. The high-ammonia nitrogen wastewater concentrated in the forward osmosis membrane assembly is sent to a short-cut nitrification / anaerobic ammonium oxidation reactor. The ammonia nitrogen in the high-ammonia nitrogen wastewater undergoes short-cut nitrification and anaerobic ammonium oxidation. The effluent from the short-cut nitrification / anaerobic ammonium oxidation reactor enters a methane denitrification reactor for denitrification treatment, and the methane produced by the anaerobic digestion treatment is used as the carbon source required for denitrification to remove the nitrate nitrogen in the effluent from the short-cut nitrification / anaerobic ammonium oxidation reactor, thereby obtaining a second high-quality effluent. The recovery device of the present invention can realize energy recovery and efficient utilization of organic matter in high-ammonia nitrogen organic wastewater, and at the same time, the high-concentration ammonia nitrogen in the wastewater is efficiently removed, and two high-quality water products are obtained, thereby realizing efficient recovery of water resources and improving the quality of produced water.

[0028] In some embodiments, the anaerobic bioreactor includes one of a fully mixed anaerobic reactor, an upflow anaerobic sludge blanket reactor, an expanded granular sludge blanket, and an anaerobic baffle reactor; the forward osmosis membrane assembly includes an active layer and a support layer, the active layer includes cellulose triacetate, and the support layer includes polyester fiber; the short-range nitrification / anaerobic ammonia oxidation reactor includes one of a continuous flow reactor, a sequencing batch reactor, a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor; the methane denitrification reactor includes one of an upflow anaerobic sludge blanket reactor, an anaerobic baffle reactor, a fully mixed anaerobic reactor, and an internal circulation anaerobic reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of a device for recovering high-ammonia nitrogen organic wastewater according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0031] The method for recovering high-ammonia nitrogen organic wastewater according to the embodiment of the present invention comprises:

[0032] a. Sending high-ammonia nitrogen organic wastewater into an anaerobic bioreactor for anaerobic digestion treatment to obtain methane and high-ammonia nitrogen wastewater;

[0033] b. The high ammonia nitrogen wastewater and the draw liquid obtained in step a are respectively fed to the raw liquid side and the draw liquid side of the forward osmosis membrane module for forward osmosis treatment;

[0034] c. sending the effluent from the draw liquid side after forward osmosis treatment in step b to a nanofiltration membrane assembly to obtain the first produced water after nanofiltration treatment;

[0035] d. The concentrated high-ammonia nitrogen wastewater from the raw material liquid side after forward osmosis treatment in step b is sent to a short-cut nitrification / anaerobic ammonium oxidation reactor for short-cut nitrification and anaerobic ammonium oxidation treatment;

[0036] e. The effluent after the anaerobic ammonium oxidation treatment in step d and the methane produced in step a are sent to a methane denitrification reactor for denitrification treatment to obtain a second produced water.

[0037] In the method of the embodiment of the present invention, high-concentration ammonia nitrogen organic wastewater is first subjected to anaerobic digestion treatment to achieve the removal of organic matter, and a part of the generated methane is sent to the subsequent methane denitrification reactor as a carbon source for denitrification, and the other part can be used as fuel for energy recovery; the high-ammonia nitrogen wastewater with organic matter removed produced by anaerobic digestion treatment is subjected to forward osmosis treatment using a forward osmosis membrane assembly under the action of an extraction liquid, and the diluted extraction liquid is subjected to nanofiltration treatment to obtain a high-quality first-pass produced water, so that water resources are recovered, and the high-ammonia nitrogen wastewater concentrated by forward osmosis is subjected to short-cut nitrification in a short-cut nitrification / anaerobic ammonia oxidation reactor, and part of the ammonia nitrogen in the high-ammonia nitrogen wastewater is subjected to short-cut nitrification to generate Nitrite nitrogen, the generated nitrite nitrogen and the remaining ammonia nitrogen in the high-ammonia nitrogen wastewater are treated by anaerobic ammonia oxidation to generate nitrogen and nitric nitrogen; the effluent from the short-cut nitrification / anaerobic ammonia oxidation reactor enters the methane denitrification reactor for denitrification treatment, and the methane generated by anaerobic digestion treatment is used as the carbon source required for denitrification to remove nitrate nitrogen in the effluent from the short-cut nitrification / anaerobic ammonia oxidation reactor, thereby obtaining a second high-quality effluent. After the recovery treatment of the method of the present invention, energy recovery and efficient utilization of organic matter in high-ammonia nitrogen organic wastewater are achieved, while high-concentration ammonia nitrogen in the wastewater is efficiently removed, and two high-quality produced water is obtained, thereby achieving efficient recovery of water resources and improving the quality of produced water.

[0038] In some embodiments, in step a, the high-ammonia nitrogen organic wastewater is sent to the anaerobic bioreactor after removing floating matter and / or suspended matter through the grid well. In the embodiment of the present invention, the high-ammonia nitrogen organic wastewater is first treated through the grid well to remove more than 85% of floating matter and larger suspended matter.

[0039] In some embodiments, in step a, the anaerobic bioreactor comprises one of a fully mixed anaerobic reactor, an upflow anaerobic sludge blanket reactor, an expanded granular sludge blanket, and an anaerobic baffled reactor.

[0040] In some embodiments, in step a, the methane obtained is recovered by the gas recovery device and then partially sent to the fuel recovery system, and the other part is sent to the methane denitrification reactor in step e. In the embodiment of the present invention, the methane obtained by anaerobic digestion is used as a carbon source for the subsequent denitrification reaction, and part of the methane is recovered as fuel for standby use, so that the organic matter in the wastewater is fully recycled.

[0041] In some embodiments, in step b, the draw liquid includes at least one of sodium chloride, sodium sulfate, disodium ethylenediaminetetraacetate or a scale inhibitor. Preferably, the scale inhibitor includes at least one of diethylenetriaminepenta(methylenephosphonic acid)heptasodium, hydrolyzed polymaleic anhydride, sodium polyaspartate, 2-acrylamide-2-methylpropanesulfonic acid, aminotri(methylenesulfonic acid)sulfuric acid, sodium hydroxyethyldiphosphonate, polyepoxysuccinic acid, 2-phospho-1,2,4-tricarboxylic acid butane, sodium polymethacrylate, and sodium molybdate. In the embodiment of the present invention, a scale inhibitor is preferably used as the draw liquid. The scale inhibitor has a certain osmotic pressure. The scale inhibitor is used as the draw liquid for forward osmosis treatment. After use, there is no need for separation treatment. The draw liquid can be directly sent to the circulating cooling water system to play a scale inhibition role, thereby saving the energy consumption of the draw liquid regeneration. At the same time, nanofiltration treatment has a higher retention rate for the scale inhibitor, and the draw liquid concentration can be more efficiently achieved, thereby improving the treatment effect of the wastewater.

[0042] In some embodiments, the concentration of the drawn liquid is 30-500 g / L, preferably 100-400 g / L; more preferably, the concentration of sodium chloride is not less than 30 g / L; the concentration of sodium sulfate is not less than 40 g / L; the concentration of diethylenetriamine penta (methylene phosphonic acid) is not less than 51 g / L; the concentration of sodium polyaspartate is not less than 93 g / L; the concentration of sodium molybdate is not less than 89 g / L; the concentration of sodium hydroxyethylidene diphosphonate is not less than 105 g / L; the concentration of polyepoxysuccinic acid is not less than 113 g / L; the concentration of 2-phospho-1,2,4-tricarboxylic acid butane is not less than 141 g / L; the concentration of aminotri (methylene) sulfuric acid is not less than 165 g / L; the concentration of sodium polymethacrylate is not less than 198 g / L; the concentration of hydrolyzed polymaleic anhydride is not less than 252 g / L; and the concentration of 2-acrylamide-2-methylpropane sulfonic acid is not less than 269 g / L. In the embodiment of the present invention, the preferred draw liquid concentration is used to further improve the concentration ratio of the wastewater, increase the proportion of the first produced water obtained by nanofiltration treatment, and thus achieve effective recovery of high-quality water.

[0043] In some embodiments, in step b, the forward osmosis membrane assembly includes an active layer and a support layer, the active layer includes cellulose triacetate, and the support layer includes polyester fiber, wherein the active layer faces the high ammonia nitrogen wastewater side.

[0044] In some embodiments, in step d, the short-cut nitrification / anaerobic ammonium oxidation reactor comprises one of a continuous flow reactor, a sequencing batch reactor, a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor.

[0045] In some embodiments, in step d, the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor is aerated to control the dissolved oxygen in the lower part of the reactor to 0.2-0.4 mg / L, and the upper part of the reactor is in an anaerobic state. In the embodiment of the present invention, the high-ammonia nitrogen wastewater after forward osmosis concentration enters the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor, and the ammonia nitrogen in the wastewater is partially converted into nitrite nitrogen through short-cut nitrification. The remaining ammonia nitrogen and nitrite nitrogen in the wastewater are converted into nitrogen gas by anaerobic ammonium oxidizing bacteria under anaerobic conditions to remove the ammonia nitrogen.

[0046] In some embodiments, in step e, the methane denitrification reactor comprises one of an upflow anaerobic sludge blanket reactor, an anaerobic baffle reactor, a completely mixed anaerobic reactor, and an internal circulation anaerobic reactor.

[0047] like Figure 1 As shown, an embodiment of the present invention also provides a recovery device for high-ammonia nitrogen organic wastewater, including an anaerobic bioreactor 3, a forward osmosis membrane assembly 6, a nanofiltration membrane assembly 10, a short-cut nitrification / anaerobic ammonium oxidation reactor 13 and a methane denitrification reactor 16, wherein the water outlet of the anaerobic bioreactor 3 is connected to the water inlet on the raw liquid side of the forward osmosis membrane assembly 6, and the methane gas outlet of the anaerobic bioreactor 3 is connected to the gas inlet of the gas recovery device 4; the water outlet on the draw liquid side of the forward osmosis membrane assembly 6 is connected to the water inlet on the concentrated water side of the nanofiltration membrane assembly 10, and the water outlet on the raw liquid side of the forward osmosis membrane assembly 6 is connected to the bottom water inlet of the short-cut nitrification / anaerobic ammonium oxidation reactor 13; the water outlet of the short-cut nitrification / anaerobic ammonium oxidation reactor 13 is connected to the water inlet of the methane denitrification reactor 16; the gas inlet of the methane denitrification reactor 16 is connected to the gas outlet of the gas recovery device 4.

[0048] The high-ammonia nitrogen organic wastewater recovery device of the embodiment of the present invention can remove organic matter from high-concentration ammonia nitrogen organic wastewater in an anaerobic bioreactor, and the generated methane is sent to a methane denitrification reactor as a carbon source for denitrification. The high-ammonia nitrogen wastewater with organic matter removed is concentrated under the action of the draw liquid by using a forward osmosis membrane assembly. The diluted draw liquid is treated in a nanofiltration membrane assembly to obtain a high-quality first-pass water product. The high-ammonia nitrogen wastewater concentrated in the forward osmosis membrane assembly is sent to a short-cut nitrification / anaerobic ammonium oxidation reactor. The ammonia nitrogen in the high-ammonia nitrogen wastewater undergoes short-cut nitrification and anaerobic ammonium oxidation. The effluent from the short-cut nitrification / anaerobic ammonium oxidation reactor enters a methane denitrification reactor for denitrification treatment, and the methane produced by the anaerobic digestion treatment is used as the carbon source required for denitrification to remove the nitrate nitrogen in the effluent from the short-cut nitrification / anaerobic ammonium oxidation reactor, thereby obtaining a second high-quality effluent. The recovery device of the present invention can realize energy recovery and efficient utilization of organic matter in high-ammonia nitrogen organic wastewater, and at the same time, the high-concentration ammonia nitrogen in the wastewater is efficiently removed, and two high-quality water products are obtained, thereby realizing efficient recovery of water resources and improving the quality of produced water.

[0049] In some embodiments, the anaerobic bioreactor includes one of a fully mixed anaerobic reactor, an upflow anaerobic sludge blanket reactor, an expanded granular sludge blanket, and an anaerobic baffle reactor; the forward osmosis membrane assembly includes an active layer and a support layer, the active layer includes cellulose triacetate, and the support layer includes polyester fiber; the short-range nitrification / anaerobic ammonium oxidation reactor includes one of a continuous flow reactor, a sequencing batch reactor, a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor; the methane denitrification reactor includes one of an upflow anaerobic sludge blanket reactor, an anaerobic baffle reactor, a fully mixed anaerobic reactor, and an internal circulation anaerobic reactor. In the embodiments of the present invention, there is no particular limitation on the anaerobic bioreactor, the short-range nitrification / anaerobic ammonium oxidation reactor, the methane denitrification reactor, the forward osmosis membrane assembly, and the nanofiltration membrane assembly, and the anaerobic bioreactor, the short-range nitrification / anaerobic ammonium oxidation reactor, the methane denitrification reactor, and the forward osmosis membrane assembly and the nanofiltration membrane assembly commonly used in the art can all be applied to the present invention.

[0050] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0051] Example 1

[0052] like Figure 1As shown, the high-ammonia nitrogen organic wastewater device includes an anaerobic bioreactor 3, a forward osmosis membrane assembly 6, a nanofiltration membrane assembly 10, a short-cut nitrification / anaerobic ammonium oxidation reactor 13 and a methane denitrification reactor 16, wherein the water outlet of the anaerobic bioreactor 3 is connected to the water inlet on the raw liquid side of the forward osmosis membrane assembly 6, and the methane gas outlet of the anaerobic bioreactor 3 is connected to the gas inlet of the gas recovery device 4; the water outlet on the draw liquid side of the forward osmosis membrane assembly 6 is connected to the water inlet on the concentrated water side of the nanofiltration membrane assembly 10, and the water outlet on the raw liquid side of the forward osmosis membrane assembly 6 is connected to the bottom water inlet of the short-cut nitrification / anaerobic ammonium oxidation reactor 13; the water outlet of the short-cut nitrification / anaerobic ammonium oxidation reactor 13 is connected to the water inlet of the methane denitrification reactor 16; the gas inlet of the methane denitrification reactor 16 is connected to the gas outlet of the gas recovery device 4.

[0053] The anaerobic bioreactor 3 adopts an upflow anaerobic sludge blanket reactor (USBA), which realizes the upflow and mixing of sludge by reflux. A three-phase separator is provided on the anaerobic bioreactor 3 to separate the three phases of mud, water and gas. A hole is opened above the anaerobic bioreactor 3 to connect the reactor to the pH, conductivity and ORP probes. The short-range nitrification / anaerobic ammonium oxidation reactor 13 and the methane denitrification reactor 16 both adopt an upflow anaerobic sludge blanket reactor.

[0054] The forward osmosis membrane used in the forward osmosis membrane assembly has an asymmetric structure, consisting of an active layer and a support layer. The active layer is made of cellulose triacetate (CTA), the support layer is made of polyester fiber, the total thickness of the membrane is 115μm, and the membrane pore size range is 0.3-1.0nm. Before use, the new membrane is soaked in ultrapure water 2-3 times, each time for 30 minutes, to completely remove the glycerol protective layer on the membrane surface, and then the membrane is immersed in ultrapure water and stored at 4°C. The forward osmosis membrane assembly can be a flat membrane assembly with the active layer of the membrane facing the raw liquid.

[0055] The nanofiltration membrane assembly adopts the nanofiltration membrane (model NF90-4040) produced by Dow Company of the United States. The nanofiltration membrane material is polyamide. The configuration of the nanofiltration membrane assembly can be a flat membrane assembly, and the active surface of the membrane faces the side of the drawn liquid.

[0056] Example 2

[0057] The high-ammonia nitrogen organic wastewater treated in this embodiment is: the water quality is COD 7000mg / L, NH4 + -N 220mg / L, TP3.0mg / L.

[0058] The recovery device of Example 1 is used to treat high ammonia nitrogen organic wastewater.

[0059] The high-ammonia nitrogen organic wastewater is first sent to the grid well to filter and remove floating objects and larger suspended matter, and then homogenized in the sewage collection tank 1. The wastewater in the sewage collection tank 1 is pumped into the anaerobic bioreactor 3 through the water inlet pump 2. The anaerobic bioreactor is a UASB reactor with a height-to-diameter ratio of 8 and a hydraulic retention time of 24 hours. The sludge taken from the anaerobic digestion tank of the sewage treatment plant is inoculated in the anaerobic bioreactor 3. The initial sludge concentration is 3500 mg / L. After anaerobic digestion, most of the organic matter in the high-ammonia nitrogen organic wastewater is removed to obtain high-ammonia nitrogen wastewater and produce methane, which is collected in the gas recovery device 4. The water quality of the high-ammonia nitrogen wastewater is COD 200 mg / L, NH4 + -N 230mg / L, TP 3.0mg / L, biogas recovery rate is 32%.

[0060] The high-ammonia nitrogen wastewater after anaerobic digestion treatment is pumped into the raw liquid side of the forward osmosis membrane assembly 6 through the water inlet pump 5. A 150g / L sodium sulfate solution is used as the draw liquid. The draw liquid in the draw liquid tank 8 is sent to the draw liquid side of the forward osmosis membrane assembly 6 through the circulation pump 7. The water in the high-ammonia nitrogen wastewater passes through the forward osmosis membrane into the draw liquid, and the high-ammonia nitrogen wastewater is concentrated. The draw liquid diluted by forward osmosis is returned to the draw liquid tank 8 and pumped into the nanofiltration membrane assembly 10 through the water inlet pump 9. After being concentrated by the nanofiltration membrane assembly 10, the draw liquid is returned to the draw liquid tank 8 through the concentrated water reflux pump 11 to maintain the osmotic pressure of the draw liquid. The wastewater concentration ratio can reach 3 times. The water quality of the first produced water after nanofiltration treatment by the nanofiltration membrane assembly 10 is: COD 30mg / L, NH4 + -N 4mg / L, TP0.8mg / L.

[0061] The high ammonia nitrogen wastewater measured by the raw liquid after forward osmosis concentration treatment is pumped into the short-range nitrification / anaerobic ammonium oxidation reactor 13 through the inlet pump 12. The inlet water quality is: COD 600mg / L, NH4 + -N 670mg / L, TP 8.5mg / L. The short-cut nitrification / anaerobic ammonium oxidation reactor 13 is a UASB reactor with a height-to-diameter ratio of 8 and a hydraulic retention time of 24h. Micro-aeration at the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor 13 controls the dissolved oxygen in the lower part of the reactor to 0.3mg / L, and the upper part of the reactor is in an anaerobic state. Short-cut nitrifying bacteria and anaerobic ammonium oxidizing bacteria coexist in the short-cut nitrification / anaerobic ammonium oxidation reactor 13. The effluent quality of the high-ammonia nitrogen wastewater concentrated by forward osmosis treatment after short-cut nitrification and anaerobic ammonium oxidation treatment is: COD 200mg / L, NH4 + -N 5mg / L, NO3 - -N 95mg / L, TP 2.5mg / L.

[0062] The wastewater treated by the short-cut nitrification / anaerobic ammonium oxidation reactor 13 is pumped into the methane denitrification reactor 16 through the water inlet pump 14. The reactor is a UASB reactor with a height-to-diameter ratio of 8 and a hydraulic retention time of 24 hours. The methane collected in the gas recovery device 4 is passed into the methane denitrification reactor 16 through the gas flow meter 15. 3 The flow rate of methane gas is controlled at 600L / h to control the COD / TN concentration ratio in the wastewater to 5:1 to ensure sufficient carbon source. After denitrification treatment in the methane denitrification reactor 16, nitrate and nitrogen are deeply removed, and the quality of the second produced water is: COD 45mg / L, NH4 + -N 5mg / L, NO3- - N 8mg / L, TN 14mg / L, TP 0.9mg / L.

[0063] In this embodiment, the first produced water obtained after the nanofiltration treatment accounts for 67% of the total produced water, and the second produced water obtained after the denitrification treatment accounts for 33% of the total produced water.

[0064] Example 3

[0065] The method is the same as that of Example 2, except that the draw solution used in the forward osmosis treatment includes 150 g / L DT-PMP-Na7 solution.

[0066] The quality of the first produced water after the nanofiltration membrane assembly in this embodiment is: COD 21mg / L, NH4 + -N 4mg / L, TP 0.8mg / L.

[0067] The quality of the second produced water after denitrification treatment in the methane denitrification reactor in this embodiment is: COD 45mg / L, NH4 + -N5mg / L, NO3 - -N 8mg / L, TN 15mg / L, TP 1.0mg / L.

[0068] In this embodiment, the first produced water obtained after the nanofiltration treatment accounts for 70% of the total produced water, and the second produced water obtained after the denitrification treatment accounts for 30% of the total produced water.

[0069] Example 4

[0070] The method is the same as that of Example 1, except that the draw solution used in the forward osmosis treatment includes 150 g / L sodium polyaspartate solution.

[0071] The quality of the first produced water after the nanofiltration membrane module treatment in this embodiment is: COD 25mg / L, NH4 + -N 5mg / L, TP 0.9mg / L.

[0072] The quality of the second produced water after denitrification treatment in the methane denitrification reactor in this embodiment is: COD 45mg / L, NH4 + -N5mg / L, NO3 - -N 9mg / L, TN 15mg / L, TP 1.0mg / L.

[0073] In this embodiment, the first produced water obtained after the nanofiltration treatment accounts for 69% of the total produced water, and the second produced water obtained after the denitrification treatment accounts for 31% of the total produced water.

[0074] Comparative Example 1

[0075] The forward osmosis membrane assembly, nanofiltration membrane assembly, anaerobic bioreactor, short-cut nitrification / anaerobic ammonium oxidation reactor, methane denitrification reactor, high-ammonia nitrogen organic wastewater and drawn liquid used in the method of Example 2 are the same, except that the high-ammonia nitrogen organic wastewater first enters the forward osmosis membrane assembly, specifically:

[0076] Pump the high-ammonia nitrogen organic wastewater in the sewage collection tank 1 into the raw liquid side of the forward osmosis membrane module, and send the draw liquid in the draw liquid tank to the draw liquid side of the forward osmosis membrane module. The water in the high-ammonia nitrogen organic wastewater passes through the forward osmosis membrane into the draw liquid, and the high-ammonia nitrogen organic wastewater is concentrated. The draw liquid diluted by forward osmosis is sent to the nanofiltration membrane module for concentration treatment, and the concentrated draw liquid is returned to the draw liquid tank to maintain the osmotic pressure of the draw liquid. The first water quality after nanofiltration treatment by the nanofiltration membrane module is: COD 200mg / L, NH4 + -N 40mg / L, TP 1.5mg / L.

[0077] The high-ammonia nitrogen organic wastewater measured in the raw material liquid after forward osmosis concentration treatment is sent to an anaerobic bioreactor for anaerobic digestion treatment to remove organic matter, thereby obtaining high-ammonia nitrogen wastewater and methane, and the methane is collected in a gas recovery device.

[0078] The high ammonia nitrogen wastewater obtained by the anaerobic bioreactor treatment is pumped into the short-cut nitrification / anaerobic ammonium oxidation reactor. Micro-aeration at the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor controls the dissolved oxygen in the lower part of the reactor to 0.3 mg / L, and the upper part of the reactor is in an anaerobic state, so as to carry out short-cut nitrification and anaerobic ammonium oxidation treatment.

[0079] The wastewater treated by the short-cut nitrification / anaerobic ammonium oxidation reactor is sent to the methane denitrification reactor, and the methane collected in the gas recovery device is passed into the methane denitrification reactor. The flow rate of the methane gas is controlled to control the COD / TN concentration ratio of the wastewater to 5:1 to ensure sufficient carbon source. The water quality of the second produced water after denitrification treatment in the methane denitrification reactor is: COD 80mg / L, NH4 + -N 10mg / L, NO3- -N 15mg / L, TN 28mg / L, TP 1.5mg / L.

[0080] In this comparative example, the first produced water obtained after the nanofiltration treatment accounts for 52% of the total produced water, and the second produced water obtained after the denitrification treatment accounts for 48% of the total produced water.

[0081] Comparative Example 2:

[0082] The anaerobic bioreactor, short-cut nitrification / anaerobic ammonium oxidation reactor, methane denitrification reactor and high-ammonia nitrogen organic wastewater used in the method of Example 2 are the same, except that the high-ammonia nitrogen organic wastewater does not pass through the forward osmosis membrane assembly and the nanofiltration membrane assembly after being treated by the anaerobic bioreactor, specifically:

[0083] The high-ammonia nitrogen organic wastewater in the sewage collection pool 1 is pumped into the anaerobic bioreactor 3. After anaerobic digestion, most of the organic matter in the high-ammonia nitrogen organic wastewater is removed to obtain high-ammonia nitrogen wastewater and generate methane, which is collected in the gas recovery device 4.

[0084] The high-ammonia nitrogen wastewater after anaerobic digestion treatment is pumped into the short-cut nitrification / anaerobic ammonium oxidation reactor 13. Micro-aeration at the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor 13 controls the dissolved oxygen in the lower part of the reactor to 0.3 mg / L, and the upper part of the reactor is in an anaerobic state. Short-cut nitrifying bacteria and anaerobic ammonium oxidizing bacteria coexist in the short-cut nitrification / anaerobic ammonium oxidation reactor 13.

[0085] The wastewater treated by the short-cut nitrification / anaerobic ammonium oxidation reactor 13 is pumped into the methane denitrification reactor 16, and the methane collected in the gas recovery device 4 is introduced into the methane denitrification reactor 16. The flow rate of the introduced methane gas is controlled to control the COD / TN concentration ratio of the wastewater to 5:1 to ensure sufficient carbon source. The water quality of the produced water after denitrification treatment by the methane denitrification reactor 16 is: COD 60mg / L, NH4 + -N 5mg / L, NO3- - N 15mg / L, TN 24mg / L, TP 1.2mg / L.

[0086] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0087] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for recovering high-ammonia nitrogen organic wastewater, characterized in that: include: a. Sending high-ammonia nitrogen organic wastewater into an anaerobic bioreactor for anaerobic digestion treatment to obtain methane and high-ammonia nitrogen wastewater; b. The high ammonia nitrogen wastewater and the draw liquid obtained in step a are respectively fed to the raw liquid side and the draw liquid side of the forward osmosis membrane module for forward osmosis treatment; c. sending the effluent from the draw liquid side after forward osmosis treatment in step b to a nanofiltration membrane assembly to obtain the first produced water after nanofiltration treatment; d. The concentrated high-ammonia nitrogen wastewater from the raw material liquid side after forward osmosis treatment in step b is sent to a short-cut nitrification / anaerobic ammonium oxidation reactor for short-cut nitrification and anaerobic ammonium oxidation treatment; e. The effluent after the anaerobic ammonium oxidation treatment in step d and the methane produced in step a are sent to a methane denitrification reactor for denitrification treatment to obtain a second produced water.

2. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step a, the high-ammonia nitrogen organic wastewater is sent to the anaerobic bioreactor after removing floating matter and / or suspended matter through the grid well; And / or, the anaerobic bioreactor comprises one of a fully mixed anaerobic reactor, an upflow anaerobic sludge blanket reactor, an expanded granular sludge blanket, and an anaerobic baffled reactor; And / or, the obtained methane is recovered by the gas recovery device and part of it is sent to the fuel recovery system, and the other part is sent to the methane denitrification reactor in step e.

3. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step b, the draw liquid includes at least one of sodium chloride, sodium sulfate, disodium ethylenediaminetetraacetate or a scale inhibitor. Preferably, the scale inhibitor includes at least one of diethylenetriaminepenta(methylenephosphonic acid)heptasodium, hydrolyzed polymaleic anhydride, sodium polyaspartate, 2-acrylamide-2-methylpropanesulfonic acid, aminotri(methylenesulfonic acid)sulfuric acid, sodium hydroxyethylidene diphosphonate, polyepoxysuccinic acid, 2-phospho-1,2,4-tricarboxylic acid butane, sodium polymethacrylate and sodium molybdate.

4. The method for recovering high-ammonia nitrogen organic wastewater according to claim 3, characterized in that: In the step b, the concentration of the drawn liquid is 30-500 g / L, preferably 100-400 g / L; Further preferably, the concentration of sodium chloride is not less than 30g / L; the concentration of sodium sulfate is not less than 40g / L; the concentration of diethylenetriaminepenta(methylenephosphonic acid)heptasodium is not less than 51g / L; the concentration of sodium polyaspartate is not less than 93g / L; the concentration of sodium molybdate is not less than 89g / L; the concentration of sodium hydroxyethylidene diphosphonate is not less than 105g / L; the concentration of polyepoxysuccinic acid is not less than 113g / L; the concentration of 2-phospho-1,2,4-tricarboxylic acid butane is not less than 141g / L; the concentration of aminotri(methylene)sulfuric acid is not less than 165g / L; the concentration of sodium polymethacrylate is not less than 198g / L; the concentration of hydrolyzed polymaleic anhydride is not less than 252g / L; and the concentration of 2-acrylamide-2-methylpropanesulfonic acid is not less than 269g / L.

5. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step b, the forward osmosis membrane assembly comprises an active layer and a supporting layer, the active layer comprises cellulose triacetate, and the supporting layer comprises polyester fiber, wherein the active layer faces the high ammonia nitrogen wastewater side.

6. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step d, the short-cut nitrification / anaerobic ammonium oxidation reactor includes one of a continuous flow reactor, a sequencing batch reactor, a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor.

7. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step d, the bottom of the short-cut nitrification / anaerobic ammonium oxidation reactor is aerated to control the dissolved oxygen in the lower part of the reactor to 0.2-0.4 mg / L, and the upper part of the reactor is in an anaerobic state.

8. The method for recovering high-ammonia nitrogen organic wastewater according to claim 1, characterized in that: In the step e, the methane denitrification reactor includes one of an upflow anaerobic sludge blanket reactor, an anaerobic baffle reactor, a completely mixed anaerobic reactor, and an internal circulation anaerobic reactor.

9. A device for recovering high-ammonia nitrogen organic wastewater, characterized in that: It includes anaerobic bioreactor, forward osmosis membrane module, nanofiltration membrane module, short-range nitrification / anaerobic ammonium oxidation reactor and methane denitrification reactor, among which: The water outlet of the anaerobic bioreactor is connected to the water inlet on the raw liquid side of the forward osmosis membrane assembly, and the methane gas outlet of the anaerobic bioreactor is connected to the gas inlet of the gas recovery device; The water outlet on the draw liquid side of the forward osmosis membrane assembly is connected to the water inlet on the concentrated water side of the nanofiltration membrane assembly, and the water outlet on the raw liquid side of the forward osmosis membrane assembly is connected to the bottom water inlet of the short-range nitrification / anaerobic ammonium oxidation reactor; The water outlet of the short-cut nitrification / anaerobic ammonium oxidation reactor is connected to the water inlet of the methane denitrification reactor; The gas inlet of the methane denitrification reactor is connected to the gas outlet of the gas recovery device.

10. The high-ammonia nitrogen organic wastewater recovery device according to claim 9, characterized in that: The anaerobic bioreactor includes one of a fully mixed anaerobic reactor, an upflow anaerobic sludge blanket reactor, an expanded granular sludge blanket, and an anaerobic baffled reactor; And / or, the forward osmosis membrane assembly comprises an active layer and a support layer, the active layer comprises triacetyl cellulose, and the support layer comprises polyester fiber; And / or, the short-cut nitrification / anaerobic ammonium oxidation reactor comprises one of a continuous flow reactor, a sequencing batch reactor, a one-stage PN / A reactor, and an upflow anaerobic sludge blanket reactor; And / or, the methane denitrification reactor includes one of an upflow anaerobic sludge blanket reactor, an anaerobic baffle reactor, a completely mixed anaerobic reactor, and an internal circulation anaerobic reactor.

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