A high-temperature chemical anaerobic system

Abstract

The present invention discloses a high-temperature chemical anaerobic system for the field of organic waste treatment, which includes a pretreatment device, an anaerobic device, and a biogas slurry treatment device. The pretreatment device includes a hydrolysis fluidization component, and the hydrolysis liquid outlet of the hydrolysis fluidization component leads to the inlet of the anaerobic device. The biogas slurry treatment device includes a deep anaerobic reactor, an aerobic nitrification reactor, and an anaerobic ammonia oxidation reactor connected in sequence, and the concentrated liquid outlet of the anaerobic device leads to the inlet of the deep anaerobic reactor. By setting the hydrolysis fluidization component, the present invention greatly reduces the suspended solids of the waste, converts some insoluble COD under conventional processes into soluble COD that is easy to biochemically treat, improves the biodegradability of the organic matter, and also makes the gas production rate of the process higher than that of the conventional process. In addition, by adopting a deep anaerobic reactor, an aerobic nitrification reactor, and an anaerobic ammonia oxidation reactor, the combination of aerobic and anaerobic ammonia oxidation processes is used to solve the problem of ammonia nitrogen in biogas slurry at low cost.

Description

Technical Field

[0001] The present invention relates to the field of organic waste treatment, and particularly to a high-temperature chemical anaerobic system. Background Art

[0002] High-water-content organic waste includes medicine sludge, breeding manure, human feces, kitchen waste, municipal sludge, food industrial sludge, etc. At present, the common method for treating it is anaerobic biochemical treatment. After anaerobic biochemical treatment, biogas slurry will be produced, and substances such as NH3 and PO in the biogas slurry have the greatest impact on the environment. If discharged without treatment, these substances will cause pollution to environmental water bodies. Currently, there is a process for treating biogas slurry by anaerobic ammonium oxidation process. However, the COD in biogas slurry is generally high, and the anaerobic ammonium oxidation process system has certain requirements for the COD of water quality, and the proliferation of ANAMMOX (red bacteria) in the system is also relatively sensitive to COD; the current anaerobic ammonium oxidation process rarely considers how to reduce the COD in biogas slurry. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a high-temperature chemical anaerobic system, which can treat organic waste with low energy consumption and low cost.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A high-temperature chemical anaerobic system includes a pretreatment device, an anaerobic device, and a biogas slurry treatment device. The pretreatment device includes a hydrolysis fluidization component, and the hydrolysis liquid outlet of the hydrolysis fluidization component leads to the inlet of the anaerobic device. The biogas slurry treatment device includes a deep anaerobic reactor, an aerobic nitrification reactor, and an anaerobic ammonium oxidation reactor connected in sequence, and the concentrated liquid outlet of the anaerobic device leads to the inlet of the deep anaerobic reactor.

[0006] As a further improvement of the present invention, the pretreatment device further includes a homogenization component, and the slurry outlet of the homogenization component leads to the hydrolysis fluidization component.

[0007] As a further improvement of the present invention, the homogenization component includes a homogenization tank and a homogenization tank. The outlet of the homogenization tank is provided with a cutting pump, the outlet of the cutting pump is provided with a feeding pump, the outlet of the feeding pump is connected to the homogenization tank through a pipeline, and the outlet of the homogenization tank is connected to the hydrolysis fluidization component through a pipeline.

[0008] As a further improvement of the present invention, the hydrolysis fluidization component includes a fluidized bed body, a housing, and a steam distributor. The top of the fluidized bed body is provided with an overflow port, the bottom is provided with a sludge discharge port, and the pretreatment device is provided with a slurry inlet leading to the inside of the fluidized bed body; the housing is sleeved outside the fluidized bed body, and an overflow cavity is formed between the housing and the fluidized bed body. The top of the housing is provided with an ammonia outlet communicating with the overflow cavity, and the bottom of the housing is also provided with a hydrolysis liquid outlet leading to the overflow cavity. The steam distributor is arranged at the bottom of the fluidized bed body and is externally connected to a steam input pipe.

[0009] As a further improvement of the present invention, the pretreatment device further comprises a pressure relief tower and an ammonia crystallizer. The ammonia outlet of the fluidized bed body leads to the ammonia crystallizer, the hydrolyzed liquid outlet of the fluidized bed body is connected to the pressure relief tower, and the outlet of the pressure relief tower is connected to the anaerobic device.

[0010] As a further improvement of the present invention, the deep anaerobic reactor has a liquid inlet, a biogas outlet, a liquid outlet and a liquid return port. An aeration component is arranged in the aerobic nitrification reactor. The liquid outlet of the deep anaerobic reactor leads to the inlet of the aerobic nitrification reactor. The liquid inlet of the anaerobic ammonium oxidation reactor communicates with the liquid outlet of the aerobic nitrification reactor, and the liquid outlet of the anaerobic ammonium oxidation reactor leads to a transfer container.

[0011] As a further improvement of the present invention, the aerobic nitrification reactor is provided with a sludge discharge port. The sludge discharge port of the aerobic nitrification reactor is connected to the sludge return port of the deep anaerobic reactor through a pipeline and a reflux pump arranged on the pipeline.

[0012] As a further improvement of the present invention, a reflux device is arranged between the transfer container and the liquid return port of the deep anaerobic reactor.

[0013] As a further improvement of the present invention, the biogas slurry treatment device further comprises a biogas slurry pond and a solid-liquid separator. The solid-liquid separator has a biogas residue outlet, a biogas slurry outlet and a suction inlet leading to the biogas slurry pond. The concentrated liquid outlet of the anaerobic device is introduced into the biogas slurry pond through a pipeline, and the biogas slurry outlet of the solid-liquid separator communicates with the liquid inlet of the deep anaerobic reactor.

[0014] As a further improvement of the present invention, the deep anaerobic reactor is provided with a sludge discharge port. The sludge discharge port of the deep anaerobic reactor and the sludge discharge port of the aerobic nitrification reactor are connected in parallel through a pipeline and then led to the biogas slurry pond.

[0015] The beneficial effects of the present invention are as follows: By arranging the hydrolysis fluidization component, the present invention greatly reduces the suspended solids (SS) of the waste, and converts some insoluble COD under the conventional process into soluble COD that is easy to biochemically treat, improving the biodegradability of the organic matter and also making the gas production rate of the process higher than that of the conventional process. In addition, by adopting the deep anaerobic reactor, the aerobic nitrification reactor and the anaerobic ammonium oxidation reactor, the problem of ammonia nitrogen in the biogas slurry is solved at low cost by using the combination of aerobic and anaerobic ammonium oxidation processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the drawings and embodiments.

[0017] Figure 1 is the process schematic diagram of the present invention;

[0018] Figure 2 is the schematic diagram of the pretreatment device;

[0019] Figure 3 is a schematic diagram of the hydrolysis fluidization component;

[0020] Figure 4 is a schematic diagram of the biogas slurry treatment device. Specific embodiments

[0021] Such as Figure 1 The high-temperature chemical anaerobic system shown includes a pretreatment device, an anaerobic device 2, and a biogas slurry treatment device. The pretreatment device includes a hydrolysis fluidization component 1, and the hydrolysis liquid outlet of the hydrolysis fluidization component 1 leads to the inlet of the anaerobic device 2. The function of the hydrolysis fluidization component 1 is to accelerate the decomposition of organic matter in the organic waste, break the chemical bonds of the organic matter, turn the organic matter with long molecular chains into organic matter with short molecular chains, and some substances that are difficult to decompose in traditional anaerobic reactors become biodegradable substances after passing through the hydrolysis fluidization component 1, so that the biodegradability of the organic waste is greatly improved. Thus, the liquid (hydrolysis liquid) discharged into the anaerobic device 2 is relatively easy to treat. The specific structure of the pretreatment device will be described below.

[0022] The above biogas slurry treatment device includes a deep anaerobic reactor 3, an aerobic nitrification reactor 4, and an anaerobic ammonia oxidation reactor 5 connected in sequence. The concentrated liquid outlet of the anaerobic device 2 leads to the inlet of the deep anaerobic reactor 3, and the concentrated liquid (biogas slurry) is discharged into the deep anaerobic reactor 3. The function of the biogas slurry treatment device is to treat the biogas slurry generated by the system. In the embodiment, the deep anaerobic reactor 3 adopts medium-temperature anaerobic. After the biogas slurry is treated by the deep anaerobic reactor 3, it becomes dilute biogas slurry, and the dilute biogas slurry flows into the aerobic nitrification reactor 4 under the action of gravity. The deep anaerobic reactor 3 and the aerobic nitrification reactor 4 form an A / O process combination for phosphorus removal and continued removal of organic matter in the sewage, providing an electron acceptor for the subsequent anaerobic ammonia oxidation process; the biogas slurry after aerobic treatment flows into the anaerobic ammonia oxidation reactor 5. The advantage of using the anaerobic ammonia oxidation process to treat the biogas slurry is to remove TN and NH3 without using the carbon source of the biogas slurry.

[0023] The following describes the pretreatment device.

[0024] Combined with reference to Figure 2 And Figure 3 , the pretreatment device further includes a homogenization component 6, and the sewage slurry outlet of the homogenization component 6 leads to the hydrolysis fluidization component 1. The homogenization component 6 is used to disperse the solid matter in the organic waste by stirring, cutting or other means and mix it with water to form a sewage slurry shape, which is convenient for subsequent treatment in the hydrolysis fluidization component 1.

[0025] The homogenization component 6 includes a homogenization tank 61 and a homogenization vessel 62. Inside the homogenization tank 61, there is a stirring paddle. At the outlet of the homogenization tank 61, there is a cutting pump 63. While the outlet of the cutting pump 63 is connected to a feeding pump 64, it can also return to the homogenization tank 61 through a pipeline. The outlet of the feeding pump 64 is connected to the homogenization vessel 62 through a pipeline, and the outlet of the homogenization vessel 62 is connected to the hydrolysis and fluidization component 1 through a pipeline. Organic waste can be mixed with water in the homogenization tank 61, pre-mixed by the stirring paddle 65, and then output and homogenized after being transported and stirred by the cutting pump 63; during the stirring process, the organic waste circulates between the homogenization tank 61 and the cutting pump 63, and the impurities brought in by the organic waste are crushed under the repeated cutting of the cutting pump 63; the stirred and cut organic waste is diluted into slurry, and the slurry continuously circulates, stirs, and cuts until the homogenization tank 61 is filled with slurry and the stirring ends, and then the slurry is pumped into the homogenization vessel 62 by the slurry feeding pump 64. There is also a stirrer inside the homogenization vessel 62 to keep the slurry uniform.

[0026] On the pipeline connecting the homogenization vessel 62 and the hydrolysis and fluidization component 1, there is a feeding and pressurizing component. The said feeding and pressurizing component can input the slurry into the hydrolysis and fluidization component 1, and at the same time boost the pressure of the slurry to a suitable value, so that the slurry and the hydrolysis and fluidization component 1 have appropriate pressure values. The preferred feeding and pressurizing component is a high-pressure piston pump 66.

[0027] The above-mentioned hydrolysis and fluidization component 1 has a hydrolysis liquid outlet, an ammonia gas outlet 121, a slurry inlet 122, and a steam inlet, where the slurry inlet is connected to the high-pressure piston pump 66 to input the homogenized slurry into the hydrolysis and fluidization component 1. In the hydrolysis and fluidization component 1, the slurry is heated so that the nutrients in the slurry are hydrolyzed into substances such as polysaccharides, organic acids, peptides, and enzymes. When the protein is hydrolyzed, the nitrogen element NH4 + is decomposed into unstable free ammonia HN3·H2O (hydrated ammonia), and the unstable free ammonia further turns into ammonia gas and is discharged through the ammonia gas outlet 121 under the action of heat.

[0028] The pretreatment device also includes a heat exchanger 17. The heat exchanger 17 is a plate heat exchanger, which connects the hydrolysis liquid outlet of the hydrolysis and fluidization component 1 to the subsequent process device, and at the same time connects the outlet of the homogenization component to the slurry inlet 122. The slurry entering the slurry inlet 122 can be heated using the heat in the hydrolysis liquid, so that the system reasonably utilizes heat and saves costs.

[0029] The following describes the hydrolysis and fluidization component 1.

[0030] The hydrolysis and fluidization component 1 includes a fluidized bed body 11, a shell 12, and a steam distributor 13.

[0031] The fluidized bed body 11 is in the shape of a container, with an open top forming an overflow port 14. The hydrolyzed liquid overflowing in the fluidized bed body 11 can flow out to the outside from the overflow port 14. A sludge discharge port is provided at the bottom of the fluidized bed body 11, and the slurry inlet 122 leads into the fluidized bed body 11 and is externally connected to a feed pipe; the feed pipe is at a position higher than the sludge discharge port but also close to the bottom of the fluidized bed body 11.

[0032] The steam distributor 13 is arranged at the bottom of the fluidized bed body 11, and its steam injection direction is preferably upward and leads into the fluidized bed body 11, forming water vapor rising from bottom to top. The steam distributor 13 is externally connected to a steam inlet pipe 111 through a steam inlet, for introducing high-pressure and high-temperature water vapor into the interior of the fluidized bed body 11.

[0033] The outer shell 12 is sleeved outside the fluidized bed body 11 and makes the fluidized bed body 11 located in the middle. The top wall of the outer shell 12 is spaced from the overflow port 14 in the height direction, and the outer wall of the outer shell 12 is spaced from the outer wall of the fluidized bed body 11 to form an overflow chamber. The hydrolyzed liquid flowing out from the overflow port 14 can enter the overflow chamber. A hydrolyzed liquid outlet leading to the overflow chamber is also provided at the bottom of the outer shell 12, for discharging the hydrolyzed liquid in the overflow chamber out of the outer shell 12. The ammonia outlet 121 is arranged at the top of the outer shell 12 and communicates with the overflow chamber, to discharge the ammonia generated during hydrolysis. The ammonia outlet 121 is connected with a discharge valve 123, for controlling the discharge of ammonia.

[0034] Then the process of hydrolysis and fluidization using the hydrolysis and fluidization component 1 is as follows:

[0035] The slurry is input into the fluidized bed body 11. At this time, the fluidized bed body 11 can be in a high-temperature and high-pressure state by preheating and pressurizing in advance, or the high-temperature and high-pressure slurry can be directly input into the closed fluidized bed body 11; the high-temperature water vapor enters the fluidized bed body 11 through the steam distributor 13 to further heat up the slurry; at this time, the organic matter in the slurry will decompose rapidly, the chemical bonds of the organic matter will break, and the organic matter with long molecular chains will become organic matter with short molecular chains. Some substances that are difficult to decompose in traditional anaerobic reactors become biodegradable substances after passing through the fluidized bed body 11, and the biodegradability of the slurry is greatly improved; some of the already decomposed hydrolyzed liquid will cross the fluidized bed body 11 and enter the overflow chamber. The substances that have not been decomposed will continue to stay in the fluidized bed body 11 for decomposition due to their relatively large specific gravity; due to being in a high-temperature and high-pressure state, some of the organic matter and ammonia in the hydrolyzed liquid will become gas containing ammonia, which is discharged from the ammonia outlet 121, and the ammonia will be discharged to the ammonia crystallizer 16 described later for crystallization; after operating for a period of time, some non-decomposable organic matter (such as cellulose) and inorganic matter (such as fixed carbon, stone powder, etc.) will remain in the fluidized bed body 11. To ensure the hydrolysis effect, the sludge discharge port is opened for sludge discharge in a certain production cycle.

[0036] The above process can also be simply summarized as follows: The sewage slurry enters the fluidized bed body 11. Among them, the lighter suspended substances rise upward under the impetus of high-temperature and high-pressure steam, overflow from the fluidized bed body 11, and flow to the mud discharge port at the bottom. The materials with larger particle size and heavier weight descend along the inner cavity wall and are washed and hydrolyzed by steam again, and so on in a cycle; during the process of the sewage slurry and steam rising, heat exchange occurs between the steam and the sewage slurry, and the steam condenses into water and mixes into the sewage slurry.

[0037] The principle of the above process is as follows: During the fluidization process of the sewage slurry in the device, due to the action of heat, the nutrients in the sewage slurry are hydrolyzed into substances such as polysaccharides, organic acids, peptides, and enzymes. When proteins are hydrolyzed, the nitrogen element NH4 + is decomposed into unstable free ammonia HN3·H2O (hydrated ammonia). Under the action of heat, the unstable free ammonia further becomes ammonia gas and is regularly released through the exhaust valve provided at the top of the tower. The reaction formulas related to hydrolysis and deamination are as follows:

[0038] 1). NH4 + +OH - →NH3·H2O

[0039] 2). NH3·H2O→NH3↑+H2O

[0040] Through high-temperature hydrolysis, the organic matter is hydrolyzed and acidified into hydrolysis liquid. In this embodiment, high-temperature water steam can be used as the fluidization gas for solid organic matter and the stripping gas for NH3, and at the same time is the medium for providing the hydrolysis temperature. The high-temperature water steam is also at high pressure to maintain the pressure inside the fluidized bed body 11 and heat the sewage slurry inside the fluidized bed body 11 to 120 - 190°C.

[0041] The above-mentioned heat exchanger 17 has a cold inlet and a hot outlet that are interconnected, and a hot inlet and a cold outlet that are interconnected. Among them, the hot outlet of the heat exchanger 17 is connected to the sewage slurry inlet 122, the cold inlet leads to the homogenizing tank 62, the hot inlet of the heat exchanger 17 is connected to the hydrolysis liquid outlet through a pipeline, and the cold outlet leads to the pressure relief tower 15 described below.

[0042] The above-mentioned high-pressure piston pump 66 is used to pressurize the sewage slurry to an appropriate pressure value and then input it into the fluidized bed body 11, so that the fluidized bed body 11 is "preset" with pressure.

[0043] The sewage slurry is pressurized to 0.5 - 1.5 Mpa by the high-pressure piston pump 66, and then enters the heat exchanger 17. Using the high-temperature hydrolysis liquid after fluidized hydrolysis as the heat source, the sewage slurry is preheated to 100 - 150°C; then the above-mentioned hydrolysis process is carried out; after hydrolysis, the hydrolysis liquid enters the heat exchanger 17 for cooling (the heat is used to preheat the newly incoming sewage slurry), and the temperature drops to 40 - 60°C and is sent to the subsequent process.

[0044] In the above implementation, referring to the above reaction formula 2: NH4+ +OH - → NH3·H2O. This equation is reversible. In an acidic environment with a pH value of 4.5 - 5.8, when the hydrolysis temperature decreases, the free ammonia will react back to ammonium, causing the pH of the hydrolysis solution to rise, as shown in the following reaction equation 3:

[0045] 3). NH3·H2O → NH4 + +OH -

[0046] According to reaction equations 1), 2), and 3), it can be seen that the amount of ammonium released in the sewage slurry can be achieved by adjusting the acidity. The precipitation of ammonia gas is closely related to the dissolved oxygen (DO) and hydrolysis temperature of the hydrolysis solution. Then, by adding sodium hydroxide solution in proportion before the booster piston pump to change the acidity of the sewage slurry and controlling the hydrolysis temperature, the effective control of ammonia nitrogen in the hydrolysis solution can be achieved. The pH should be adjusted to a weak acidic range of 5.8 - 6.8.

[0047] The pretreatment device also includes a pressure relief tower 15 and an ammonia crystallizer 16.

[0048] The inlet of the pressure relief tower 15 is connected to the hydrolysis solution outlet of the fluidized bed body 11 through a pipeline to receive the hydrolysis solution discharged by the hydrolysis fluidization component 1. Since the discharged hydrolysis solution has a certain pressure, the pressure relief tower 15 can release the pressure in the hydrolysis solution and also serve as a temporary storage for the hydrolysis solution, providing buffer time and maintenance time for subsequent processes. Specifically, a spray head 151 is provided at the top of the pressure relief tower 15, and the hydrolysis solution is introduced into the spray head 151 and sprayed into the inner cavity of the pressure relief tower 15. The hydrolysis solution in the pressure relief tower 15 is discharged from the bottom end.

[0049] The ammonia gas outlet 121 of the hydrolysis fluidization component 1 is connected to the ammonia crystallizer 16 through a pipeline, and a valve is also provided on this pipeline for regular discharge. The ammonia crystallizer 16 is in the shape of a container, and sulfuric acid is injected into it. Ammonia gas reacts with sulfuric acid to form ammonium sulfate. The chemical reaction equation is as follows:

[0050] 2NH3 + H2SO4 → NH 42 SO4.

[0051] The generated ammonium sulfate can be dried and used for fertilizer production after being discharged.

[0052] The pressure relief tower 15 is provided with a gas outlet at the top, and this gas outlet leads to the ammonia crystallizer 16. The gas formed after the hydrolysis solution volatilizes also contains ammonia gas, which is thus discharged into the ammonia crystallizer 16 together to form a solid state.

[0053] The top of the homogenization tank 62 is provided with an exhaust port 621 leading to the ammonia crystallizer 16 for discharging gases such as volatilized ammonia in the homogenization tank 62. The bottom of the homogenization tank 62 is provided with a sludge discharge port for discharging impurities and residues. The sludge discharge port is communicated with the sludge drain port through a sludge discharge pipe, and the discharged bottom slag can be transported out or used for drying into fertilizer.

[0054] The pressure relief tower 15 is provided with a liquid outlet at the bottom end. The liquid outlet is connected with a liquid discharge pipe, and this liquid discharge pipe can lead into the anaerobic device 2. And a reflux component 152, such as a reflux pump, is provided between the anaerobic device 2 and the homogenization component 6. The reflux component 152 returns the hydrolyzed liquid discharged from the pressure relief tower 15 to the homogenization component 6 for use as diluting organic waste.

[0055] After the above pretreatment device and process, the BOD of the hydrolyzed liquid will not decrease synchronously with the COD index, and indexes such as TN and NH3 in the hydrolyzed liquid become adjustable indexes, thus greatly enhancing the biodegradability of the organic waste.

[0056] The anaerobic device 2 in the embodiment is a CSTR (Continuous Stirred Tank Reactor), also known as a completely mixed flow reactor, and its working principle is to purify organic pollutants by means of anaerobic activated sludge in the digestion tank. Generally, the hydraulic retention time of the medium-temperature CSTR anaerobic process is 32 days, the hydrolysis time of suspended solids in the sewage is about 10d - 15d, the acidification time is about 4h, and the peak period of anaerobic bacteria gas production is about 15d. In the embodiment, since the organic waste has been pretreated by processes such as hydrolysis and acidification, in order to reduce investment and improve the effect of the anaerobic process, the embodiment adopts a high-temperature CSTR anaerobic process with a hydraulic retention time of about 15d.

[0057] The hydrolyzed liquid enters the CSTR tank from the pressure relief tower 15 through a pipeline and is fully contacted with the original anaerobic activated sludge in the tank through stirring. The organic matter in the hydrolyzed liquid is converted into biogas through the metabolism of methanogens, and the hydrolyzed liquid and the sludge are mixed into a crude biogas slurry containing a certain amount of solid matter.

[0058] The following describes the biogas slurry treatment device.

[0059] Refer to Figure 4 , and in combination with Figures 1-3 , the deep anaerobic reactor 3 is a multi-stage deep anaerobic reactor, also known as an IC anaerobic reactor. It has a liquid inlet, a biogas outlet, a liquid outlet and a liquid return port, and a three-phase separator is also provided at the top of the deep anaerobic reactor 3. The deep anaerobic reactor 3 is a highly efficient multi-stage internal circulation reactor. Compared with the original traditional anaerobic reactor, it has less land occupation, a higher organic load, stronger shock resistance, more stable performance and simpler operation and management. When treating high-concentration organic wastewater with a COD of 10000 - 15000mg / L, the general volume load of the traditional anaerobic reactor is 5 - 8kgCOD / m 3; The volumetric loading rate of the IC anaerobic reactor can reach 15 - 30 kg COD / m 3 .

[0060] An aeration component 41 is provided in the aerobic nitrification reactor 4. The aeration component 41 is located at the bottom and can be an aeration pipe densely distributed with micropores. The aeration pipe is connected to an external air compressor 43 through a pipeline. The liquid outlet at the top of the deep anaerobic reactor 3 communicates with the inlet at the bottom of the aerobic nitrification reactor 4 by means of gravity flow.

[0061] The inlet of the anaerobic ammonium oxidation reactor 5 communicates with the liquid outlet of the aerobic nitrification reactor 4 to receive the biogas slurry after aerobic nitrification. The liquid outlet of the anaerobic ammonium oxidation reactor 5 leads to a transfer container 51.

[0062] The above-mentioned deep anaerobic reactor 3 adopts medium-temperature anaerobic. After the hydrolyzed liquid (biogas slurry) treated by the anaerobic device 2 is treated by the deep anaerobic reactor 3, the biogas generated during the anaerobic process is discharged through a pipeline from the gas collection area of the three-phase separator provided at the top of the reactor and is used for the subsequent process;

[0063] The diluted biogas slurry treated by the deep anaerobic process flows into the aerobic nitrification reactor 4 under the action of gravity. The deep anaerobic reactor 3 and the aerobic nitrification reactor 4 form an A / O process combination for phosphorus removal and continuous removal of organic matter in the sewage, providing an electron acceptor for the subsequent anaerobic ammonium oxidation process;

[0064] The biogas slurry after aerobic treatment flows into the anaerobic ammonium oxidation reactor 5. The advantage of using the anaerobic ammonium oxidation process to treat the biogas slurry is that TN and NH3 can be removed without using the carbon source of the biogas slurry.

[0065] During the above process, the biogas slurry is in full contact with the oxygen in the air ejected from the aeration pipe. The role of oxygen in the aerobic nitrification reactor is as follows:

[0066] 1), Oxidize NH4 + to generate nitrite NO2 - , providing an electron acceptor for the anaerobic ammonium oxidation process;

[0067] 2), The aerobic nitrification reactor 4 and the deep anaerobic reactor 3 form an A / O phosphorus fixation process;

[0068] 3), The role of oxygen in the aerobic nitrification reactor 4 also includes further removing organic matter in the sewage and increasing the dissolved oxygen (DO) of the sewage.

[0069] In addition, the combination of the deep anaerobic reactor 3, the anaerobic ammonium oxidation reactor 5 and the aerobic nitrification reactor 4 can also be regarded as an A / O phosphorus removal process.

[0070] The aerobic nitrification reactor 4 described above is provided with a sludge discharge port at the bottom end. The sludge discharge port of the aerobic nitrification reactor 4 is connected to the sludge return port of the deep anaerobic reactor 3 through a pipeline and a reflux pump 42 arranged on the pipeline.

[0071] The biogas slurry treatment device further includes a biogas slurry tank 7 and a solid-liquid separator 8. The concentrated liquid outlet of the anaerobic device 2 is connected to the biogas slurry tank 7 through a pipeline, and the biogas slurry outlet of the solid-liquid separator 8 is communicated with the liquid inlet of the deep anaerobic reactor 3.

[0072] Specifically, the bottom end of the deep anaerobic reactor 3 is also provided with a sludge discharge port. The sludge discharge port of the deep anaerobic reactor 3 and the sludge discharge port of the aerobic nitrification reactor 4 are connected in parallel through a pipeline and then lead to the biogas slurry tank 7 for adding the original biogas slurry. Correspondingly, corresponding valves are arranged on the pipeline to control the sludge discharge. At the same time, the valves can also control whether the sludge discharged from the aerobic nitrification reactor 4 is discharged to the deep anaerobic reactor 3 or the biogas slurry tank 7.

[0073] The solid-liquid separator 8 has a biogas residue outlet, a suction inlet leading to the biogas slurry tank 7, and a biogas slurry outlet leading to the filtration tank 71. The solid-liquid separator 8 is a screw dehydrator. The feed inlet of the screw dehydrator serves as the suction inlet and is connected to the biogas slurry tank 7 through a pipeline. A lift pump is arranged between the screw dehydrator and the biogas slurry tank 7, which can input the crude biogas slurry, the sludge discharged from the sludge discharge port of the aerobic nitrification reactor 4, and the sludge discharged from the sludge discharge port of the deep anaerobic reactor 3 into the screw dehydrator for solid-liquid separation; the discharge outlet of the screw dehydrator constitutes the biogas residue outlet, and the biogas residue outlet can be externally connected to a pipeline and lead to a drying device not shown in the figure. After solid-liquid separation, the inorganic substances, fixed carbon, and large particulate organic substances that have not been hydrolyzed in the crude biogas slurry are intercepted and sent to the organic fertilizer production process for treatment.

[0074] The liquid outlet of the screw dehydrator forms the biogas slurry outlet, and the biogas slurry outlet is connected to the filtration tank 71 through a pipeline. Then, the feed pump 72 lifts the biogas slurry in the filtration tank 71 to the liquid inlet of the deep anaerobic reactor 3.

[0075] Sometimes, the concentration of the biogas slurry input from the filtration tank 71 to the deep anaerobic reactor 3 may be relatively high, which is not conducive to the anaerobic reaction. Therefore, a liquid with a lower concentration (such as water) can be additionally input at the bottom of the deep anaerobic reactor 3 to dilute the concentration of the biogas slurry.

[0076] The deep anaerobic reactor 3 is provided with a liquid return port. A reflux device 52 is arranged between the transfer container 51 and the liquid return port. During the treatment process, the reflux device 52 recycles the intermediate water treated by the anaerobic ammonium oxidation reactor 5, thus saving water. In addition, the intermediate water in the transfer container 51 can also be used for long-term irrigation and other purposes.

[0077] The biogas outlet of the deep anaerobic reactor 3 is connected to a power generation device (not shown) through a pipeline, and a flame arrester water seal 31 is provided on the pipeline connecting the power generation device and the biogas outlet.

[0078] In order to enhance the ammonia nitrogen removal efficiency of the anaerobic ammonium oxidation reactor 5, fillers are arranged in the reactor as the bacterial bed for ANAMMOX (red bacteria). The principle of the anaerobic ammonium oxidation process belongs to the commonly used technology in the field, so it will not be described in detail in this embodiment.

[0079] In the embodiment, the biogas slurry initially entering the biogas slurry pond 7 needs to be adjusted for ammonia nitrogen to make the subsequent deep anaerobic feasible, and this ammonia nitrogen adjustment is realized by a pretreatment device.

[0080] The sludge in the aerobic nitrification reactor 4 contains polyphosphate-accumulating bacteria, which can be pre-cultured in the reactor or the sludge cultured with polyphosphate-accumulating bacteria can be directly injected into the reactor. After the biogas slurry in the aerobic nitrification reactor 4 enters the aerobic state, the PHB stored in the polyphosphate-accumulating bacteria undergoes aerobic decomposition and releases a large amount of energy. Part of this energy is used for the proliferation of polyphosphate-accumulating bacteria, and part is used as the energy for actively absorbing phosphate in the biogas slurry. The phosphate accumulates in the polyphosphate-accumulating bacteria in the form of polyphosphate; a large number of polyphosphate-accumulating bacteria are contained in the aerobic sludge, and the purpose of removing phosphate can be achieved through the discharge of sludge.

[0081] The sludge discharged from the aerobic nitrification reactor 4 also contains polyphosphate-accumulating bacteria. Then, in the way of reflux, the sludge refluxed to the deep anaerobic reactor 3 also contains polyphosphate-accumulating bacteria, enabling the deep anaerobic reactor 3 to also achieve the purpose of phosphorus removal.

[0082] Generally speaking, the anaerobic systems of the above embodiments have the following advantages:

[0083] 1). By adopting fluidized hydrolysis, the suspended solids (SS) in the slurry are greatly reduced, and some insoluble COD under conventional processes is converted into soluble COD that is easy to biodegrade, making the gas production rate of the process higher than that of conventional processes.

[0084] 2). By adding NaOH to adjust the ammonium saturation and pH, and combining processes such as high temperature and steam stripping, the ammonia nitrogen index can be adjusted, enhancing the biodegradability of the hydrolyzate.

[0085] 3). By using the deep anaerobic process and the aerated aerobic process, phosphorus is solidified in the biogas residue and becomes organic fertilizer.

[0086] 4). By combining the aerobic and anaerobic ammonium oxidation processes, the problem of ammonia nitrogen in the biogas slurry is solved at low cost.

[0087] 5). Through the fluidized hydrolysis process, controllable artificial hydrolysis and acidification are achieved, minimizing the hydraulic retention time of the slurry to the greatest extent. While increasing the gas production, the investment in the anaerobic system is reduced.

[0088] The above are only the preferred embodiments of the present invention, which do not constitute a limitation to the protection scope of the present invention.

Claims

1. A high-temperature chemical anaerobic system, characterized in that: It includes a pretreatment device, an anaerobic device (2) and a biogas slurry treatment device. The pretreatment device includes a hydrolysis fluidization component (1) and a homogenization component (6). The hydrolysis liquid outlet of the hydrolysis fluidization component (1) leads to the inlet of the anaerobic device (2). The sludge slurry outlet of the homogenization component (6) leads to the hydrolysis fluidization component (1). The biogas slurry treatment device includes a deep anaerobic reactor (3), an aerobic nitrification reactor (4) and an anaerobic ammonium oxidation reactor (5) connected in sequence. The concentrated liquid outlet of the anaerobic device (2) leads to the inlet of the deep anaerobic reactor (3). The homogenization component (6) includes a homogenization tank (61) and a homogenization tank (62). The outlet of the homogenization tank (61) is provided with a cutting pump (63). The outlet of the cutting pump (63) is provided with a feeding pump (64). The outlet of the feeding pump (64) is connected to the homogenization tank (62) through a pipeline. The outlet of the homogenization tank (62) is connected to the hydrolysis fluidization component (1) through a pipeline.

2. The high-temperature chemical anaerobic system according to claim 1, characterized in that: The hydrolysis fluidization component (1) includes a fluidized bed body (11), a housing (12) and a steam distributor (13). The top of the fluidized bed body (11) is provided with an overflow port (14), and the bottom is provided with a sludge discharge port. The pretreatment device is provided with a sludge slurry inlet leading to the inside of the fluidized bed body (11). The housing (12) is sleeved outside the fluidized bed body (11). An overflow chamber is formed between the housing (12) and the fluidized bed body (11). The top of the housing (12) is provided with an ammonia gas outlet (121) communicating with the overflow chamber. The bottom of the housing (12) is also provided with a hydrolysis liquid outlet leading to the overflow chamber. The steam distributor (13) is arranged at the bottom of the fluidized bed body (11) and is externally connected to a steam input pipe (111).

3. The high-temperature chemical anaerobic system according to claim 2, wherein: The pretreatment device also includes a pressure relief tower (15) and an ammonia crystallizer (16). The ammonia gas outlet (121) of the fluidized bed body (11) leads to the ammonia crystallizer (16). The hydrolysis liquid outlet of the fluidized bed body (11) is connected to the pressure relief tower (15). The outlet of the pressure relief tower (15) is connected to the anaerobic device (2).

4. The high-temperature chemical anaerobic system according to any one of claims 1 to 3, characterized in that: The deep anaerobic reactor (3) has a liquid inlet, a biogas outlet, a liquid outlet and a liquid return port. An aeration component (41) is arranged inside the aerobic nitrification reactor (4). The liquid outlet of the deep anaerobic reactor (3) leads to the inlet of the aerobic nitrification reactor (4). The liquid inlet of the anaerobic ammonium oxidation reactor (5) communicates with the liquid outlet of the aerobic nitrification reactor (4). The liquid outlet of the anaerobic ammonium oxidation reactor (5) leads to a transfer container (51).

5. The high-temperature chemical anaerobic system according to claim 4, wherein: The aerobic nitrification reactor (4) is provided with a sludge discharge port. The sludge discharge port of the aerobic nitrification reactor (4) is connected to the sludge return port of the deep anaerobic reactor (3) through a pipeline and a reflux pump (42) arranged on the pipeline.

6. The high-temperature chemical anaerobic system according to claim 4, wherein: A reflux device (52) is arranged between the transfer container (51) and the liquid return port of the deep anaerobic reactor (3).

7. The high-temperature chemical anaerobic system according to claim 4, characterized in that: The biogas slurry treatment device also includes a biogas slurry pond (7) and a solid-liquid separator (8). The solid-liquid separator (8) has a biogas residue outlet, a biogas slurry outlet and a suction inlet leading to the biogas slurry pond (7). The concentrated liquid outlet of the anaerobic device (2) is introduced into the biogas slurry pond (7) through a pipeline. The biogas slurry outlet of the solid-liquid separator (8) communicates with the liquid inlet of the deep anaerobic reactor (3).

8. The high-temperature chemical anaerobic system according to claim 7, characterized in that: The deep anaerobic reactor (3) is provided with a sludge discharge port. The sludge discharge port of the deep anaerobic reactor (3) and the sludge discharge port of the aerobic nitrification reactor (4) are connected in parallel through pipelines and then lead to the biogas slurry pond (7).

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