A method for synchronously transferring and separating carbon and phosphorus in sewage based on biological method

Abstract

The present invention belongs to the technical field of sewage treatment and resource utilization, and specifically relates to a method for the simultaneous transfer and separation of carbon and phosphorus in sewage based on a biological method. The method comprises: anaerobic mixing of pretreated sewage, microaerobic aeration, sludge removal, sedimentation, drainage, and activity enhancement; wherein, anaerobic mixing is performed for 30 to 60 minutes; microaerobic aeration is performed for 30 to 60 minutes, and the dissolved oxygen during microaerobic aeration is 0.3 mg / L to 1.8 mg / L; the sludge age is controlled at 1 to 4 days; sedimentation is performed for 30 to 60 minutes; the drainage ratio is 50% to 70%; and activity enhancement is performed for 30 to 60 minutes, and the dissolved oxygen during activity enhancement is 2.0 mg / L to 2.5 mg / L. The carbon transfer separation rate of this method can reach 60.5%, and the phosphorus transfer separation rate can reach 77.6%. Furthermore, no chemical agents are required, making it highly efficient and environmentally friendly.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment and resource utilization, and specifically relates to a method for synchronously transferring and separating carbon and phosphorus in sewage based on a biological method. Background Art

[0002] Against the backdrop of global climate change and energy and resource shortages, the urban wastewater treatment industry is facing a transformation. Green, low-carbon, and sustainable development is the future direction of the industry, and wastewater treatment is evolving from pollutant removal to resource and energy recovery. Removing and separating resources like carbon, nitrogen, and phosphorus from wastewater reduces subsequent treatment energy and chemical consumption, while simultaneously recycling resources and energy. This wastewater treatment model, which combines carbon reduction and carbon compensation, is the preferred approach.

[0003] Currently, a wide range of carbon transfer and separation technologies are available both domestically and internationally, including the most common chemically enhanced primary treatment (CEPT), high-load activated sludge (HRAS) process, anaerobic membrane bioreactor (AnMBR), and coagulation-microscreening processes. Most of these technologies focus on carbon transfer and separation. While CEPT and coagulation-microscreening processes can simultaneously transfer and separate phosphorus, these processes primarily rely on chemical methods involving the addition of chemical reagents. This chemical phosphorus transfer and separation method, particularly when high phosphorus content in the influent is present or when high phosphorus capture rates are sought, requires the addition of large amounts of chemical reagents, which is not in line with the green and low-carbon development goals for wastewater.

[0004] Therefore, a transfer and separation technology is needed to simultaneously transfer and separate carbon and phosphorus resources from sewage, and no chemical agents are used in the carbon and phosphorus transfer and separation process. Summary of the Invention

[0005] In order to solve the above problems, the purpose of the present invention is to provide a method for the simultaneous transfer and separation of carbon and phosphorus in wastewater based on biological methods, which can reduce the use of chemical agents for phosphorus transfer and separation, and realize wastewater treatment based on the biological simultaneous transfer and separation of carbon and phosphorus.

[0006] In order to achieve the above object, the present invention can adopt the following technical solutions:

[0007] The invention provides a method for synchronously transferring and separating carbon and phosphorus in sewage based on a biological method. The method comprises: anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement of pretreated sewage; wherein the anaerobic mixing is performed for 30 to 60 minutes; the microaerobic aeration is performed for 30 to 60 minutes, and the dissolved oxygen during the microaerobic aeration is 0.3 mg / L to 1.8 mg / L; the sludge age is controlled within 1 to 4 days; the sedimentation is performed for 30 to 60 minutes; the drainage ratio is 50% to 70%; and the activity is enhanced for 30 to 60 minutes, and the dissolved oxygen during the activity enhancement is 2.0 mg / L to 2.5 mg / L.

[0008] The beneficial effects of the present invention include at least:

[0009] (1) The method for the simultaneous biological transfer and separation of carbon and phosphorus in wastewater provided by the present invention has a carbon transfer separation rate of 60.5%, and a phosphorus transfer separation rate of 77.6%; and does not require the use of chemical agents, which is highly efficient and environmentally friendly.

[0010] (2) Compared with carbon transfer and separation methods such as high-load activated sludge (HRAS) process and anaerobic membrane bioreactor (AnMBR), the method provided by the present invention for simultaneous transfer and separation of carbon and phosphorus in sewage can not only transfer and separate carbon but also simultaneously transfer and separate phosphorus, integrating carbon and phosphorus transfer and separation into one and completing them simultaneously. Compared with carbon and phosphorus transfer and separation methods such as chemically enhanced primary enhancement (CEPT) and coagulation-microscreen process, which mainly use carbon transfer and separation and supplement chemical transfer of phosphorus, the transfer and separation of phosphorus in the present invention adopts a biological method, not a chemical method of adding chemical agents, and does not require the use of chemical agents.

[0011] (3) The method for the simultaneous transfer and separation of carbon and phosphorus in wastewater based on biological methods provided by the present invention is compared with the AO process, SBR process and carbon capture reactor with application number 202110800567.7, which are aimed at meeting wastewater treatment standards. The operating time of one cycle is short, the number of cycles in a day is large, which is 6 to 12 cycles, and the drainage ratio is high, which is 50% to 70%. In terms of land occupation and other aspects, it is more efficient and low-carbon. DETAILED DESCRIPTION

[0012] The examples are provided to better illustrate the present invention, but are not intended to limit the present invention to the examples. Therefore, non-essential improvements and adjustments to the embodiments made by those skilled in the art based on the above-mentioned invention still fall within the scope of protection of the present invention.

[0013] The terms used herein are only used to describe specific embodiments and are not intended to limit the present disclosure. Unless the context has a significantly different meaning, expressions in the singular include expressions in the plural. As used herein, it should be understood that terms such as "include", "have", "comprise" and the like are intended to indicate the presence of features, numbers, operations, components, parts, elements, materials or combinations. The terms of the present invention are disclosed in the specification and are not intended to exclude the possibility that one or more other features, numbers, operations, components, parts, elements, materials or combinations thereof may exist or may be added. As used herein, " / " may be interpreted as "and" or "or", depending on the circumstances.

[0014] An embodiment of the present invention provides a method for synchronous transfer and separation of carbon and phosphorus in sewage based on a biological method, which includes: anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement of pretreated sewage; wherein, anaerobic mixing is 30 minutes to 60 minutes; microaerobic aeration is 30 minutes to 60 minutes, and the dissolved oxygen during microaerobic aeration is 0.3 mg / L to 1.8 mg / L; the sludge age is controlled at 1 day to 4 days; sedimentation is 30 minutes to 60 minutes; the drainage ratio is 50% to 70%; and activity enhancement is 30 minutes to 60 minutes, and the dissolved oxygen during activity enhancement is 2.0 mg / L to 2.5 mg / L.

[0015] It should be noted that the present invention is not a technology for removing pollutants from sewage and achieving discharge standards, but rather a technology for separating organic matter and phosphorus in sewage from the aqueous phase and transferring them into sludge. It is a "pre-" treatment technology for transferring and separating carbon and phosphorus resources from sewage to realize the resource-energy conversion of sewage. Under anaerobic conditions, polyphosphate-accumulating bacteria and glycogen-accumulating bacteria absorb organic carbon sources in sewage and synthesize internal carbon sources PHAs to store in their bodies. Polyphosphate-accumulating bacteria release phosphorus at the same time. Entering the micro-aerobic aeration process, microorganisms continue to attach particulate and colloidal organic matter in sewage to the surface of microorganisms through biological adsorption. At the same time, polyphosphate-accumulating bacteria absorb phosphorus under aerobic conditions using oxygen as an electron acceptor. By discharging sludge rich in phosphorus and having a large amount of organic matter adsorbed on the surface, the transfer and separation of carbon and phosphorus resources in sewage is achieved, providing a carrier for the subsequent extraction and utilization of carbon and phosphorus for resource-energy conversion.

[0016] It should be noted that the above-mentioned pretreatment includes screen, grit chamber, and primary sedimentation tank pretreatment. Furthermore, the carbon and phosphorus separated from the wastewater are transferred to the sludge, from which they are then extracted and recycled. For example, when both carbon and phosphorus transfer and separation rates are high, the sludge can be treated through anaerobic digestion to recover methane gas for cogeneration, while the phosphorus enters the digestate and is recovered using struvite. Protein can also be extracted or used to manufacture higher value-added products.

[0017] In addition, the present invention can flexibly adjust the number of operating cycles and the time of different processes such as anaerobic, microaerobic aeration, sedimentation, and activity enhancement in each cycle, as well as the drainage ratio, dissolved oxygen, and sludge age according to the actual sewage water quality, sludge sedimentation performance, and carbon-phosphorus transfer and separation rate requirements. It can flexibly achieve carbon transfer separation as the main method, phosphorus transfer separation as the main method, or a coordinated combination of carbon and phosphorus simultaneous transfer and separation to achieve the optimal result, without the need to use chemical agents to capture phosphorus.

[0018] It should be understood that water intake, anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement are carried out in the same unit in chronological order, first water anaerobic mixing, then microaerobic aeration, then sludge discharge, then sedimentation, then drainage and then activity enhancement.

[0019] In some specific embodiments, the aforementioned anaerobic mixing, microaerobic aeration, sludge removal, sedimentation, drainage, and activation enhancement of pretreated wastewater constitute a cycle, with 6 to 12 cycles being run daily. It should be noted that upon completion of a cycle, the carbon and phosphorus resources in the wastewater are separated and transferred into sludge, which is then used for energy extraction and utilization. After a cycle is completed, the process continues, with the next cycle of water intake, anaerobic mixing, microaerobic aeration, sludge removal, sedimentation, drainage, and activation enhancement repeating over and over again.

[0020] In some specific embodiments, the COD of the sewage is 180 mg / L to 600 mg / L, and the orthophosphate concentration is 2 mg / L to 8 mg / L.

[0021] In some specific embodiments, the COD of the above-mentioned sewage is 180 mg / L~400 mg / L, the orthophosphate concentration is 2 mg / L~4 mg / L, anaerobic mixing is 30 minutes~60 minutes, microaerobic aeration is 30 minutes~60 minutes, the dissolved oxygen during microaerobic aeration is 0.4 mg / L~0.8 mg / L, the sludge age is 4 days, sedimentation is 30~60 minutes, the drainage ratio is 60%, the activity is enhanced for 30~60 minutes, and the dissolved oxygen during activity enhancement is 2.0 mg / L~2.5 mg / L.

[0022] In some specific embodiments, the COD of the sewage is 180 mg / L to 400 mg / L, the orthophosphate concentration is 2 mg / L to 4 mg / L, the influent is anaerobic mixed for 60 minutes, microaerobic aeration is 90 minutes, the average dissolved oxygen during microaerobic aeration is 0.5 mg / L, the sludge age is 4 days, the sedimentation and drainage is 45 minutes, the drainage ratio is 60%, the activity is enhanced for 45 minutes, and the dissolved oxygen during the activity enhancement is 2.0 mg / L.

[0023] In some specific embodiments, the COD of the above-mentioned sewage is 450 mg / L~600 mg / L, the orthophosphate concentration is 6 mg / L~8 mg / L, anaerobic mixing is 30 minutes to 60 minutes, microaerobic aeration is 30 minutes to 60 minutes, the dissolved oxygen during microaerobic aeration is 1.5 mg / L~1.8 mg / L, the sludge age is 1.5 days, sedimentation is 30 minutes to 60 minutes, the drainage ratio is 60%, the activity is enhanced for 30 minutes to 60 minutes, and the dissolved oxygen during activity enhancement is 2.0 mg / L~2.5 mg / L.

[0024] In some specific embodiments, the COD of the sewage is 450 mg / L to 600 mg / L, the orthophosphate concentration is 6 mg / L to 8 mg / L, the influent is anaerobic mixed for 45 minutes, microaerobic aeration is 60 minutes, the dissolved oxygen during microaerobic aeration is an average of 1.8 mg / L, the sludge age is 1.5 days, the sedimentation is 45 minutes, the drainage ratio is 60%, the activity is enhanced for 30 minutes, and the dissolved oxygen during the activity enhancement is 2.5 mg / L.

[0025] It should be noted that, as described above, the present invention can flexibly adjust the number of operating cycles of the carbon-phosphorus synchronous transfer and separation unit and the time of different processes such as anaerobic, microaerobic aeration, sedimentation and activity enhancement in each cycle, as well as the level of dissolved oxygen, drainage ratio and sludge age, etc., according to water quality conditions such as the organic matter and phosphorus content and organic matter properties in sewage, sludge sedimentation performance and required carbon-phosphorus transfer and separation rate, so as to achieve the optimal effect of synchronous transfer and separation of carbon and phosphorus.

[0026] For example, when the influent COD is about 500 mg / L and the phosphate is about 6 mg / L, the carbon-phosphorus synchronous transfer and separation unit operates for 8 cycles, the drainage ratio is 60%, and the sludge age is 1 day. In each cycle, the time for different processes of influent + anaerobic, microaerobic aeration + sludge discharge, sedimentation + drainage, and activity enhancement is controlled at 45 minutes, 60 minutes, 45 minutes, and 30 minutes, respectively. The dissolved oxygen of microaerobic aeration is controlled at about 1.8 mg / L, and the dissolved oxygen of activity enhancement is controlled at about 2.5 mg / L.

[0027] When the concentrations of organic matter and phosphorus in the influent decrease, the carbon-phosphorus synchronous transfer and separation unit reduces its operating cycles or lowers the discharge ratio, prolonging the anaerobic and microaerobic aeration reaction times, lowering the dissolved oxygen control value during the microaerobic aeration process, and increasing the sludge age. For example, when COD is 200mg / L to 400mg / L and phosphate is around 3mg / L, the carbon-phosphorus synchronous transfer and separation unit operates for 6 cycles, with a discharge ratio of 60% and a sludge age of 4 days. Within each cycle, the durations for the influent + anaerobic, microaerobic aeration + sludge discharge, sedimentation + discharge, and activation enhancement processes are controlled at 60 minutes, 90 minutes, 45 minutes, and 45 minutes, respectively. The dissolved oxygen during microaerobic aeration is controlled at around 0.5mg / L, and the dissolved oxygen during activation enhancement is controlled at around 2.0mg / L.

[0028] It should be noted that the present invention can realize the simultaneous transfer and separation of carbon and phosphorus in sewage by biological methods, and can also flexibly adjust the number of operating cycles and the time of different processes in each cycle, the drainage ratio, the dissolved oxygen level, the sludge age, etc. according to the actual water quality conditions such as the carbon and phosphorus content of sewage and the required carbon and phosphorus transfer and separation rate, so as to flexibly realize carbon transfer separation as the main method or phosphorus transfer separation as the main method. When carbon transfer separation is mainly used, the number of operating cycles of the transfer and separation unit can be increased or its drainage ratio can be increased relative to the simultaneous transfer and separation of carbon and phosphorus, shortening the anaerobic reaction time so that the anaerobic reaction process can act as a selector to improve the sludge settling performance, appropriately increase the sedimentation time and active regeneration time, reduce the dissolved oxygen control value of the microaerobic aeration process, and shorten the sludge age; when phosphorus transfer separation is mainly used, the sedimentation time and active regeneration time can be appropriately reduced relative to the simultaneous transfer and separation of carbon and phosphorus, and the dissolved oxygen control value of the microaerobic aeration process can be increased.

[0029] It should also be noted that the method of the present invention represents a significant improvement over other existing patents related to the technology. For example, compared to the carbon capture reactor of Application No. 202110800567.7 and the carbon source capture reactor of Application No. 202111464041.2, the carbon-phosphorus simultaneous transfer and separation unit of the present invention incorporates an activation boost process after the sedimentation and drainage process. This enhances microbial activity, enabling the microorganisms to rapidly absorb readily degradable organic matter from the influent to synthesize an internal carbon source while simultaneously rapidly releasing phosphorus during the anaerobic and microaerobic reaction processes. Microorganisms undergo a certain degree of "inhibition" in the anoxic environment of sedimentation and concentration. The addition of an activation boost process after the sedimentation and drainage process restores the activity of the inhibited microorganisms, facilitating their subsequent absorption and adsorption of organic matter upon contact with wastewater. Furthermore, the process of sludge discharge, sedimentation and drainage, and activation boosting first removes phosphorus-rich sludge with a large amount of organic matter adsorbed on its surface. This prevents carbonization of adsorbed organic matter during activation boost aeration, which would reduce the carbon transfer and separation efficiency. It also prevents the re-release of phosphorus already adsorbed during the sedimentation process, which would reduce the phosphorus transfer and separation efficiency. In addition, after sludge discharge, sedimentation and drainage, the activity is increased and aeration is performed. The amount of mixed liquid that needs to be aerated is small, and the energy consumption is relatively low.

[0030] In addition, the present invention can flexibly adjust the drainage ratio according to the sludge settling performance of the carbon-phosphorus synchronous transfer and separation unit and the required carbon-phosphorus transfer and separation rate to achieve a better carbon-phosphorus transfer and separation effect.

[0031] It should also be noted that the above-mentioned method for synchronous transfer and separation of carbon and phosphorus in sewage based on biological methods can be completed based on existing facilities. For example, micro-aerobic aeration can be performed by directly connecting oxygen to the reaction tank for aeration and adjusting the aeration volume. Sludge discharge can be completed using a general sludge pump. Sedimentation can be left to settle. Drainage can use a drainage pump. Activity enhancement can be achieved by connecting to a pipeline for aeration activation. Of course, the method of the present invention does not exclude the use of new facilities or facilities modified based on existing facilities.

[0032] In some specific embodiments, the above-mentioned method for simultaneous transfer and separation of carbon and phosphorus in sewage based on biological method may include the following steps: (1) urban sewage pretreated by the grid and the grit chamber enters the carbon-phosphorus simultaneous transfer and separation unit through the water inlet through the water inlet control device of the carbon-phosphorus simultaneous transfer and separation unit, and starts the mixing or stirring device while the water is entering; (2) after the water is entered, the water inlet control device is closed, and the anaerobic mixing or stirring reaction is carried out for 30 minutes to 60 minutes; (3) after the anaerobic reaction is completed, the blower and the aeration device in the carbon-phosphorus simultaneous transfer and separation unit are started, and micro-aeration aeration is carried out for 30 minutes to 60 minutes, and mixing or stirring is carried out during aeration, and the dissolved oxygen is controlled to be maintained at 0.3 mg / L to 1.8 mg / L; (4) after the micro-aeration is completed, the sludge is discharged, and the sludge mixture is discharged to the resource and energy recovery unit or the sludge treatment unit. Unit, for subsequent sludge treatment and resource energy recovery; (5) After the sludge is discharged, the mixing or stirring device, blower and aeration device are turned off and sedimentation is carried out for 30 minutes to 60 minutes; (6) After sedimentation is completed, the drainage device is started to drain, with a drainage ratio of 50% to 70%, and the drainage is discharged to the sewage biological treatment unit through the outlet for subsequent purification treatment to meet the discharge standards; (7) After the drainage is completed, the blower and aeration device are started to increase the activity for 30 minutes to 60 minutes, and the dissolved oxygen is controlled to be maintained at 2.0 mg / L to 2.5 mg / L; (8) After the activity is increased, the blower and aeration device are turned off, and they are not idle. Then the water inlet control device and the mixing or stirring device are started to enter water and start the next cycle, continuing anaerobic mixing, micro-aerobic aeration, sludge discharge, sedimentation, drainage, and activity increase, and repeating. The sludge age of the carbon-phosphorus synchronous transfer and separation unit is controlled to be 1 to 4 days. The water inlet control device, mixing or stirring device, aeration device, blower, drainage device, and dissolved oxygen online monitoring probe of the entire system are all controlled by the SCADA system. The dissolved oxygen level is regulated and controlled through the linkage between the SCADA system and the variable frequency blower.

[0033] It should also be noted that, in addition, the method for the simultaneous transfer and separation of carbon and phosphorus in wastewater based on biological methods can be to perform water intake, anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement in a reactor in chronological order to complete a cycle. This reactor can be an intermittent reactor (the so-called intermittent is the opposite of continuous), which means that it is not continuously fed with water and aerated, etc. This reactor is actually a device / tank / unit (all commonly used in this field). After a certain amount of sewage enters this reactor, water is no longer fed. The reactor is subjected to anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement in sequence according to a pre-set time. After these processes are completed, a cycle is completed, and the next cycle is then carried out, which includes water intake, anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activity enhancement. This reactor / device / tank / unit is equipped with equipment necessary to complete the reaction, such as a water inlet pump, a sludge discharge pump or an aeration device.

[0034] In order to better understand the present invention, the content of the present invention is further explained below with reference to specific examples, but the content of the present invention is not limited to the following examples.

[0035] In the following examples, the calculation method of carbon and phosphorus transfer separation rate is as follows:

[0036]

[0037]

[0038] Example 1

[0039] The COD of urban sewage is 180 mg / L~400 mg / L, and the orthophosphate concentration is 2 mg / L~4 mg / L. After the sewage is pretreated by the screen and the grit chamber, the water inlet control device of the carbon-phosphorus synchronous transfer and separation unit is started, and the sewage enters the carbon-phosphorus synchronous transfer and separation unit through the water inlet, and the mixing or stirring device is started at the same time; after the water inlet is completed, the water inlet control device is closed, and anaerobic reaction is carried out. The anaerobic reaction of the water inlet is carried out for a total of 60 minutes; after the anaerobic mixing or stirring is completed, the blower and the aeration device in the carbon-phosphorus synchronous transfer and separation unit are started, and the aeration volume is adjusted to control the dissolved oxygen to an average of about 0.6 mg / L. Micro-aerobic aeration is carried out for 90 minutes (including sludge discharge time), and then sludge is discharged. The sludge discharge volume is discharged according to the sludge age of 4 days, and the discharged sludge is discharged to the subsequent related units using anaerobic digestion treatment; after the sludge discharge is completed, the mixing or stirring device, blower and aeration device are closed, and the mud-water mixture is settled. After the sedimentation is completed, the drainage device is started, and the water is discharged at a drainage ratio of 60%. The sedimentation and drainage take a total of 45 minutes. The drainage is discharged to the subsequent sewage biofilm treatment unit for further purification treatment to meet the discharge standards; after the drainage is completed, the blower and aeration device are started, and the aeration volume is adjusted to perform active aeration, and the dissolved oxygen is controlled to be maintained at 2.0mg / L~2.5mg / L, and aeration is carried out for 45 minutes; after the active aeration is completed, the blower and aeration device are turned off, and then the water inlet control device and the mixing or stirring device are started, water is introduced, and the next cycle begins, and anaerobic mixing or stirring, micro-aerobic aeration, sludge discharge, sedimentation, drainage, and active regeneration are continued, and repeated, with 6 cycles running every day.

[0040] The carbon transfer separation rate is about 60.5%, and the phosphorus transfer separation rate is about 77.6%. The specific calculation is as follows:

[0041] In the embodiment, the average daily concentrations of the influent COD and TP of the carbon-phosphorus synchronous transfer and separation unit on a certain day were 312 mg / L and 6.3 mg / L, respectively. The total influent volume was 2232 L and the total sludge discharge volume was 115.2 L. The average daily concentrations of the effluent COD and TP were 54 mg / L and 1.0 mg / L, respectively. The COD and TP of the discharged sludge were 3660 mg / L and 94.8 mg / L, respectively. The carbon transfer separation rate and the phosphorus transfer separation rate were calculated according to the above formula as follows:

[0042]

[0043]

[0044] The carbon and phosphorus-rich sludge is concentrated and dehydrated before undergoing advanced anaerobic digestion. The dehydrated sludge is adjusted to a solid content of 8% to 10%, and subjected to thermal hydrolysis at 0.14 MPa and 124°C for 60 minutes, followed by anaerobic digestion at medium temperature (35°C ± 0.5°C) for 22 days. The gas production per unit sludge is 20m3. 3 / m 3 The above, the degradation rate of organic matter is above 40%, and the gas production per unit organic matter removed is 0.85m 3 / kgVSS or above, solid reduction is more than 35%, and orthophosphate in the digestive fluid reaches more than 100mg / L.

[0045] Example 2

[0046] The COD of urban sewage is 450 mg / L~600 mg / L, and the orthophosphate concentration is 6 mg / L~8 mg / L. After the sewage is pretreated by the screen and the grit chamber, the water inlet control device of the carbon-phosphorus synchronous transfer and separation unit is started, and the sewage enters the carbon-phosphorus synchronous transfer and separation unit through the water inlet, and the mixing or stirring device is started at the same time; after the water inlet is completed, the water inlet control device is closed, and anaerobic reaction is carried out. The anaerobic reaction of the water inlet is carried out for a total of 45 minutes; after the anaerobic mixing or stirring is completed, the blower and the aeration device in the carbon-phosphorus synchronous transfer and separation unit are started, and the aeration volume is adjusted to control the dissolved oxygen to be maintained at an average of about 1.8 mg / L. Micro-aerobic aeration is carried out for 60 minutes (including sludge discharge time), and then sludge is discharged. The sludge discharge volume is discharged according to the sludge age of 1.5 days, and the discharged sludge is discharged to the subsequent sludge treatment related units using anaerobic digestion; after the sludge discharge is completed, the blower, aeration device and mixing or stirring device are closed, and the mud-water mixture is allowed to settle. After the sedimentation is completed, the drainage device is started, and the water is discharged at a drainage ratio of 60%. The sedimentation and drainage take a total of 45 minutes. The drainage is discharged to the sewage biofilm treatment unit for further purification treatment to meet the discharge standards; after the drainage is completed, the blower and aeration device are started, and the aeration volume is adjusted to perform activity-enhancing aeration for 30 minutes, and the DO is controlled to be maintained at around 2.5 mg / L; after the aeration is completed, the blower and aeration device are turned off, and then the water inlet control device and the mixing or stirring device are started, water is introduced, and the next cycle begins, continuing with anaerobic mixing or stirring, micro-aerobic aeration, sludge discharge, sedimentation, drainage, and activity enhancement, and repeating over and over again, with 8 cycles running every day.

[0047] The carbon transfer separation rate is about 47.1%, and the phosphorus transfer separation rate is about 73.1%. The specific calculation is as follows:

[0048] In the embodiment, the average daily concentrations of COD and TP in the influent of the carbon-phosphorus synchronous transfer and separation unit on a certain day were 501 mg / L and 7.5 mg / L, respectively. The total influent volume was 3744 L, the total sludge discharge volume was 307.2 L, the average daily concentrations of COD and TP in the effluent were 70 mg / L and 1.5 mg / L, respectively. The COD and TP of the discharged sludge were 2880 mg / L and 66.8 mg / L. The carbon transfer separation rate and the phosphorus transfer separation rate were calculated according to the above formula as follows:

[0049]

[0050]

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be covered by the scope of the claims of the present invention.

Claims

1. A method for synchronously transferring and separating carbon and phosphorus in sewage based on a biological method, characterized in that: include: The pretreated sewage is anaerobically mixed, microaerobically aerated, sludge discharged, precipitated, drained and activated; wherein, anaerobic mixing is 30 minutes to 60 minutes; microaerobic aeration is 30 minutes to 60 minutes, and the dissolved oxygen during microaerobic aeration is 0.3 mg / L to 1.8 mg / L; the sludge age is controlled at 1 day to 4 days; sedimentation is 30 minutes to 60 minutes; the drainage ratio is 50% to 70%; the activation is enhanced for 30 minutes to 60 minutes, and the dissolved oxygen during activation is 2.0 mg / L to 2.5 mg / L; after drainage, the blower and aeration device are started to activate activation; water intake, anaerobic mixing, microaerobic aeration, sludge discharge, sedimentation, drainage and activation enhancement are carried out in the same unit in a chronological order, first water anaerobic mixing, then microaerobic aeration, sludge discharge, sedimentation, drainage and activation enhancement; the pretreated sewage is anaerobic mixed, microaerobic aeration, sludge discharge, sedimentation, drainage and activation enhancement as one cycle, and 6 to 12 cycles are operated daily.

2. The method for synchronously transferring and separating carbon and phosphorus in sewage based on biological method according to claim 1, characterized in that: The COD of sewage is 180 mg / L~600 mg / L, and the orthophosphate concentration is 2 mg / L~8 mg / L.

3. The method for synchronously transferring and separating carbon and phosphorus in sewage based on biological method according to claim 2, characterized in that: The COD of sewage is 180 mg / L~400 mg / L, the orthophosphate concentration is 2 mg / L~4 mg / L, anaerobic mixing is 30 minutes~60 minutes, microaerobic aeration is 30 minutes~60 minutes, the dissolved oxygen during microaerobic aeration is 0.4 mg / L~0.8 mg / L, the sludge age is 4 days, sedimentation is 30 minutes~60 minutes, the drainage ratio is 60%, activity enhancement is 30 minutes~60 minutes, and the dissolved oxygen during activity enhancement is 2.0 mg / L~2.5 mg / L.

4. The method for synchronously transferring and separating carbon and phosphorus in sewage based on biological method according to claim 2, characterized in that: The COD of sewage is 450mg / L~600mg / L, the orthophosphate concentration is 6mg / L~8mg / L, anaerobic mixing is 30 minutes~60 minutes, microaerobic aeration is 30 minutes~60 minutes, the dissolved oxygen during microaerobic aeration is 1.5mg / L~1.8 mg / L, the sludge age is 1.5 days, sedimentation is 30 minutes~60 minutes, the drainage ratio is 60%, activity enhancement is 30 minutes~60 minutes, and the dissolved oxygen during activity enhancement is 2.0mg / L~2.5mg / L.

5. The method for synchronously transferring and separating carbon and phosphorus in sewage based on biological method according to claim 2, characterized in that: The COD of the sewage is 450mg / L~600mg / L, the orthophosphate concentration is 6mg / L~8mg / L, the influent is anaerobic mixed for 45 minutes, microaerobic aeration is 60 minutes, the average dissolved oxygen during microaerobic aeration is 1.8mg / L, the sludge age is 1.5 days, the sedimentation is 45 minutes, the drainage ratio is 60%, the activity is enhanced for 30 minutes, and the dissolved oxygen during the activity enhancement is 2.5mg / L.

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