AnMBR in-situ treatment device and method for ship oily mixed wastewater

Abstract

The present invention discloses an AnMBR in-situ treatment device and method for oily mixed wastewater from ships, comprising: a reactor shell, on which a sample inlet, a mud discharge port, a backwash device and a circulating air inlet device are arranged; a membrane assembly is arranged in the shell, a stirrer is arranged in the membrane assembly, and roller brush-type frame flexible fillers are arranged inside and outside the shell; a suction pipeline is arranged in the shell, and the treated sewage is discharged to an external water collection tank through the suction pipeline, a suction pump, a liquid three-way valve and a water outlet pipe, and the liquid is sucked from the water collection tank by the suction pump, and enters the reactor shell through the backwash inlet pipe and the backwash device to wash the outside of the membrane assembly; the top of the reactor shell is provided with a membrane assembly, a stirrer is arranged in the membrane assembly, and a roller brush-type frame flexible filler is arranged inside and outside the membrane assembly; the treated sewage is discharged to an external water collection tank through the suction pipeline, a suction pump, a liquid three-way valve and a water outlet pipe, and the liquid is sucked from the water collection tank through the suction pump, and then enters the reactor shell through the backwash inlet pipe and the backwash device to wash the outside of the membrane assembly; the top of the reactor shell is provided with a membrane assembly, a stirrer is arranged in the membrane assembly, and a roller brush-type frame flexible filler is arranged inside and outside ... An air outlet is provided on the inside of the reactor shell, and the treated gas is discharged from the air outlet through the gas collecting pipeline, the first exhaust pipeline, the second exhaust pipeline and the backwashing air inlet pipeline, and is pumped into the reactor shell through the circulating air inlet device under the action of the gas circulation pump to flush the membrane assembly. The present invention can solve the contradiction between the small hull space and the complex and large floor space of the treatment device, slow down the accumulation of pollutants in the membrane assembly, reduce operating costs, increase the density of microorganisms and at the same time complete the spatial distribution of functional bacteria, improve the impact resistance of the device, and realize the comprehensive in-situ removal of carbon, nitrogen and sulfur pollutants and zero emission of harmful gases.

Description

Technical Field

[0001] The present invention relates to the technical field of ship sewage treatment, in particular to an AnMBR in-situ treatment device and method for ship oily mixed wastewater. Background Art

[0002] In recent years, with the rapid development of maritime transportation, the amount of wastewater discharged from ships has been increasing, and marine environmental protection is facing severe challenges. X and NO X After wet treatment, it will be SO4 2- and NO3 - Oily wastewater from long-haul vessels also accumulates at the bottom of the bilge, containing a complex variety of hydrocarbon pollutants. This wastewater must not be discharged indiscriminately, according to relevant regulations.

[0003] The high volume of ship traffic and crew density often result in wastewater pollutant concentrations two to three times higher than on land. Limited space on board ships prevents overly large and high-rise treatment equipment. Temperature fluctuations, ship vibration, and tilting caused by long voyages are detrimental to the stability of microbial treatment efficiency. Disposal of excess sludge on board is difficult, and wastewater contains large amounts of salts and other substances. These factors complicate wastewater treatment, making efficient in-situ treatment of mixed ship wastewater a significant challenge.

[0004] Membrane bioreactor (MBR) technology offers advantages such as high sludge-effluent separation efficiency, a small footprint, and easily regulated hydraulic retention time (HRT) and sludge retention time (SRT). Aerobic MBRs are currently widely used in ship sewage treatment. Compared to aerobic MBRs, anaerobic membrane bioreactors (AnMBRs) offer advantages such as lower energy consumption, reduced sludge production, and improved handling of complex organic matter. However, the AnMBR process still faces several challenges, including: 1) limited space on ships, making it difficult to treat large volumes of diverse wastewaters; 2) bacterial colonization and loss during treatment of high-salinity organic wastewater, making it difficult to maintain high sludge concentrations; 3) severe membrane fouling, requiring frequent membrane module replacement, resulting in high treatment costs and low efficiency; and 4) microorganisms are susceptible to environmental interference. Therefore, innovative technical solutions are urgently needed to overcome these challenges and advance integrated in-situ wastewater treatment methods for ships. Summary of the Invention

[0005] The present invention provides an AnMBR in-situ treatment device and method for ship oily mixed wastewater, so as to overcome the problems of limited equipment volume, large sludge output, difficult bacterial colonization and susceptibility to external environmental interference, serious membrane fouling, high treatment cost and low efficiency.

[0006] In order to achieve the above object, the technical solution of the present invention is:

[0007] An AnMBR in-situ treatment device for oily mixed wastewater from ships, characterized by comprising: a reactor shell, the reactor shell being provided with a sample inlet, a mud discharge port, a backwash device, and a circulating air intake device; the sample inlet and the mud discharge port being connected to the bottom of the reactor shell; a stirrer being provided in the membrane module, and roller brush-type frame flexible fillers being provided both inside and outside the membrane module;

[0008] A suction pipeline is provided in the reactor shell, and the treated sewage is discharged to an external water collection tank through the suction pipeline, the suction pump, the liquid three-way valve and the outlet pipe. The liquid is sucked from the water collection tank by the suction pump and enters the reactor shell through the backwash inlet pipe and the backwash device to wash the outside of the membrane module;

[0009] An air outlet is provided at the top of the reactor shell. The treated gas is discharged from the air outlet through the gas collecting pipeline, the first exhaust pipeline, the second exhaust pipeline and the backwashing air inlet pipeline. Under the action of the gas circulation pump, it is pumped into the interior of the reactor shell through the circulating air inlet device to flush the membrane assembly.

[0010] Furthermore, a flexible packing frame is provided on both sides of the inside and outside of the membrane assembly, the roller brush type frame flexible packing is provided on the flexible packing frame, and the flexible packing frame is connected to the mixer connecting rod at the upper end of the mixer. When the mixer rotates, the flexible packing frame and the roller brush type frame flexible packing are driven to rotate, thereby performing roller brush type friction cleaning on the outside of the membrane assembly.

[0011] Furthermore, it also includes a gas collecting device, a gas three-way valve and a third exhaust pipeline:

[0012] One end of the gas collecting device is connected to the gas outlet through the gas collecting pipeline; the other end of the gas collecting device is connected to one end of the gas three-way valve through the first exhaust pipeline; the other end of the gas three-way valve is connected to one end of the third exhaust pipeline, and the other end of the third exhaust pipeline is connected to the external collection device.

[0013] Furthermore, it also includes a sampling port, which is connected to the reactor shell.

[0014] Furthermore, it also includes a first pressure sensor and a second pressure sensor;

[0015] The first pressure sensor is provided on the suction pipeline to monitor the transmembrane pressure difference, and the second pressure sensor is provided on the gas collecting device to monitor the pressure inside the gas collecting device.

[0016] Furthermore, the mixer includes a first stirring paddle, a second stirring paddle and a third stirring paddle.

[0017] An AnMBR in-situ treatment method for ship oily mixed wastewater based on the AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1, comprising:

[0018] S1: The acclimated anaerobic sludge is inoculated into the reactor, and the ship's oily sewage, ship's domestic sewage and ship's exhaust gas scrubbing liquid enter the reactor through the inlet;

[0019] S2: Ship oily sewage, ship domestic sewage and ship exhaust gas scrubbing liquid enter the reactor through the sampling port and are mixed with anaerobic sludge under the action of the mixer, undergoing hydrolysis and acidification reactions, oil degradation reactions, sulfate reduction reactions, and autotrophic / heterotrophic denitrification reactions. The generated gas is discharged from the gas outlet and enters the gas collection device through the gas collection pipeline;

[0020] S3: The treated sewage is filtered through the membrane assembly, through the suction pipe and the liquid three-way valve, and enters the external water collecting tank through the outlet pipe under the action of the suction pump. After the membrane assembly is filtered, the suction pump is started to backwash the inside of the membrane assembly. When the first pressure sensor reaches the set pressure value, the valve connected to the liquid three-way valve and the backwashing water inlet pipe is opened. The treated sewage flows back to the bottom of the membrane assembly through the backwashing water inlet pipe under the action of the suction pump, and the outside of the membrane assembly is flushed through the backwashing device; the gas in the gas collecting device reaches the bottom of the membrane assembly through the first exhaust pipe, the second exhaust pipe and the backwashing air inlet pipe through the action of the gas circulation pump, and the outside of the membrane assembly is backwashed by gas through the circulating air inlet device.

[0021] Furthermore, when the transmembrane pressure difference monitored by the first pressure sensor is 30-40 KPa, the suction pump is started to perform liquid backwashing on the outside of the membrane assembly.

[0022] Furthermore, an intermittent reflux method is used to perform backwashing inside the membrane module, and the time when the membrane module is stopped is consistent with the time when the suction pump performs backwashing operation inside the membrane module.

[0023] Beneficial effects: The present invention provides an AnMBR in-situ treatment device for ship oily mixed wastewater, which has the following advantages:

[0024] 1. By setting a rolling brush frame flexible filler in the reactor, it is beneficial to the fixation and spatial separation of functional bacteria. The shear force of the water flow generated by the rotation of the frame and the contact with the membrane assembly rubs the surface of the membrane, slowing down the accumulation of pollutants in the membrane assembly.

[0025] 2. Only one reaction chamber is set up to introduce ship domestic sewage and exhaust gas washing waste liquid to dilute oily sewage for integrated comprehensive treatment, solving the contradiction between the small space of the hull and the complex and large area occupied by the treatment equipment;

[0026] 3. Equipped with a gas outlet connected to the gas collecting device, the gas generated by the reaction can be circulated to flush the membrane components, realizing the resource reuse of the gas;

[0027] 4. The treated water and gas are set up in different pipelines, which can be used to backwash the membrane components separately, reducing operating costs, preventing membrane pollution, and extending the service life of the membrane components. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 This is a structural diagram of the AnMBR in-situ treatment device for ship oily mixed wastewater provided by the present invention;

[0030] Figure 2 This is a structural diagram of the flexible packing frame and the roller brush frame suspended flexible packing of the AnMBR in-situ treatment device for ship oily mixed wastewater provided by the present invention;

[0031] Figure 3 This is a structural diagram of the mixer and roller brush frame suspended flexible filler of the AnMBR in-situ treatment device for ship oily mixed wastewater provided by the present invention;

[0032] Figure 4 This is a structural diagram of the membrane assembly of the AnMBR in-situ treatment device for ship oily mixed wastewater provided by the present invention;

[0033] Figure 5 A top view of the membrane assembly and suspended filler of the AnMBR in-situ treatment device for ship oily mixed wastewater provided by the present invention;

[0034] Figure 6 Flow chart of the AnMBR in-situ treatment method for ship oily mixed wastewater provided by the present invention;

[0035] Figure 7 The oil removal rate and SO4 2- 、NO3 - and TOC removal efficiency diagram;

[0036] In the figure, 1. reactor shell; 2. air outlet; 3. roller brush frame suspended flexible packing; 4. membrane assembly; 5. mixer; 6. suction pipeline; 7. first pressure sensor; 8. suction pump; 9. liquid three-way valve; 10. water outlet pipe; 11. backwash water inlet pipe; 12. injection port; 13. sampling port; 14. backwash device; 15. circulating air intake device; 16. first stirring paddle; 17. second stirring paddle; 18. third stirring paddle; 19. backwash air inlet pipeline; 20. gas circulation pump; 21. gas collecting device; 22. gas collecting pipeline; 23. first exhaust pipeline; 24. second exhaust pipeline; 25. second pressure sensor; 26. gas three-way valve; 27. third exhaust pipeline; 28. mud discharge port; 29. ​​flexible packing frame; 30. mixer connecting rod. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] This embodiment provides an AnMBR in-situ treatment device for ship oily mixed wastewater, such as Figure 1 As shown, it comprises: a reactor shell 1, on which a sample inlet 12, a mud discharge port 28, a backwash device 14 and a circulating air inlet device 15 are provided; the sample inlet 12 and the mud discharge port 28 are connected to the bottom of the reactor shell 1; a stirrer 5 is provided in the membrane assembly 4, and a roller brush frame flexible filler 3 is provided inside and outside the membrane assembly 4;

[0039] A suction pipe 6 is provided in the reactor shell 1. The treated sewage is discharged to an external water collection tank through the suction pipe 6, a suction pump 8, a liquid three-way valve 9 and a water outlet pipe 10. The treated sewage is then sucked from the water collection tank by the suction pump 8 and enters the reactor shell 1 through the backwash inlet pipe 11 and the backwash device 14 to wash the outside of the membrane module 4.

[0040] An air outlet 2 is provided at the top of the reactor shell 1. The treated gas is discharged from the air outlet 2 through the gas collecting pipeline 22, the first exhaust pipeline 23, the second exhaust pipeline 24 and the backwashing air inlet pipeline 19. Under the action of the gas circulation pump 20, it is pumped into the interior of the reactor shell 1 through the circulating air inlet device 15 to flush the membrane assembly 4.

[0041] Specifically, the reactor is an AnMBR reactor, and the bottom of the reactor shell is provided with an inlet, a mud discharge port, a backwash device and a circulating air intake device, the inlet and the mud discharge port are respectively arranged on both sides of the bottom of the reactor, and the backwash device and the circulating air intake device are arranged at the center of the bottom of the reactor;

[0042] A roller brush frame biological filler and a ring-type membrane assembly are provided inside the reactor, a stirrer is provided inside the membrane assembly, and an air outlet is provided on the upper part of the reactor. The air outlet is connected to a gas collecting device for collecting various gases generated inside the reactor. The collected gases enter the circulating air intake device through the gas circulation pipeline under the action of the gas circulation pump. The treated sewage passes through the suction pump and the water outlet from the pumping pipeline flows into the external water collecting tank. When the membrane is contaminated, external clean water can be drawn by suction 8 or the treated water can enter the reactor through the backwashing inlet pipe and the backwashing device to wash the outside of the membrane assembly.

[0043] In specific implementation, Figure 2 and Figure 3 As shown, a flexible packing frame 29 is provided on both sides of the inner and outer sides of the membrane assembly 4, the roller brush type frame flexible packing 3 is provided on the flexible packing frame 29, and the flexible packing frame 29 is connected to the mixer connecting rod 30 at the upper end of the mixer 5. The mixer 5 rotates, driving the flexible packing frame 29 and the roller brush type frame flexible packing 3 to rotate, and performing roller brush type friction cleaning on the outside of the membrane assembly 4.

[0044] Specifically, the flexible filler adopts biological rope soft artificial water grass, which is made of glass fiber and rigid fiber, simulating the shape of natural water grass, and the roller brush frame flexible filler is fixed on the flexible filler frame, such as Figure 2 As shown, a cross-shaped mixer connecting rod is provided at the top of the mixer, as shown in FIG. Figure 3 As shown, the membrane assembly is a ring-type membrane assembly, such as Figure 4 As shown, flexible filler frames are provided on both sides of the membrane assembly, such as Figure 5 As shown, the mixer connecting rod is connected to the flexible packing frame on the inner side of the membrane assembly and then passes through the membrane assembly to be connected to the flexible packing frame on the outer side. The mixer rotates, driving the flexible packing frame connected to it and the roller brush frame flexible packing wrapped around the flexible packing frame to rotate, performing roller brush friction cleaning on the inside and outside of the membrane assembly.

[0045] The setting of the roller brush type flexible filler is conducive to the fixation and proliferation of functional bacteria with physiological structures such as flagella, so as to quickly form a biofilm, so that microorganisms suitable for growing in suspended sludge have a larger growth space, realize the spatial distribution of functional bacteria, and are conducive to the performance of various degradation functions. Therefore, the addition of the frame type flexible filler can fix the functional bacterial community, prevent the loss of bacterial species, and is not easily disturbed by the external environment during the water treatment process, so that autotrophic bacteria can grow better in suspended sludge, and heterotrophic bacteria can attach to the biofilm, reducing the competition of multiple colonies on the same attachment body.

[0046] In a specific embodiment, Figure 1 As shown, it also includes a gas collecting device 21, a gas three-way valve 26 and a third exhaust pipeline 27:

[0047] One end of the gas collecting device 21 is connected to the gas outlet 2 through the gas collecting pipe 22; the other end of the gas collecting device 21 is connected to one end of the gas three-way valve 26 through the first exhaust pipe 23; the other end of the gas three-way valve 26 is connected to one end of the third exhaust pipe 27, and the other end of the third exhaust pipe 27 is connected to an external collection device.

[0048] In this embodiment, a gas collecting device is provided to collect intermediate products such as hydrogen sulfide produced by the reaction for gas circulation to flush the membrane components, thereby realizing the resource reuse of sulfur.

[0049] In a specific embodiment, Figure 1 As shown, it also includes a sampling port 13, which is connected to the reactor shell 1.

[0050] In this embodiment, the sampling port can also be used as a water outlet to sample or drain the reactor and to inspect and repair the reactor.

[0051] In a specific embodiment, Figure 1 As shown, it also includes a first pressure sensor 7 and a second pressure sensor 25;

[0052] The first pressure sensor 7 is provided on the suction pipeline 6 to monitor the transmembrane pressure difference, and the second pressure sensor 25 is provided on the gas collecting device 21 to monitor the pressure inside the gas collecting device 21 .

[0053] The first pressure sensor is set to monitor the transmembrane pressure difference. When the set pressure difference is reached, the valve is opened to flush the membrane assembly. The second pressure sensor is set to ensure the safe operation of the system and prevent excessive pressure from damaging the device.

[0054] In a specific embodiment, the stirrer 5 includes a first stirring paddle 16 , a second stirring paddle 17 and a third stirring paddle 18 .

[0055] The mixer is equipped with three stirring paddles, which are used in conjunction with the annular membrane components and roller brush frame fillers to increase membrane flux. The hydraulic cross-flow flushing of the membrane components can reduce membrane pollution.

[0056] An in-situ treatment method for ship oily mixed wastewater AnMBR based on the ship oily mixed wastewater AnMBR in-situ treatment device according to claim 1, such as Figure 6 Shown, including:

[0057] S1: The acclimated anaerobic sludge is inoculated into the reactor, and the ship's oily sewage, ship's domestic sewage and ship's exhaust gas scrubbing liquid enter the reactor through the inlet 12;

[0058] S2: Ship oily sewage, ship domestic sewage and ship exhaust gas washing liquid enter the reactor through the sampling port 12 and are mixed with anaerobic sludge under the action of the mixer 5, causing hydrolysis and acidification reactions, oil degradation reactions, sulfate reduction reactions and autotrophic / heterotrophic denitrification reactions. The generated gas is discharged from the gas outlet 2 and enters the gas collection device 21 through the gas collection pipeline 22;

[0059] S3: The treated sewage is filtered by the membrane component 4, passes through the suction pipe 6 and the liquid three-way valve 9, and enters the external water collecting tank through the outlet pipe 10 under the action of the suction pump 8. After the membrane component 4 is filtered, the suction pump 8 is started to backwash the inside of the membrane component 4. When the first pressure sensor 7 reaches the set pressure value, the valve connected to the liquid three-way valve 9 and the backwashing water inlet pipe 11 is opened. The treated sewage flows back to the bottom of the membrane component 4 through the backwashing water inlet pipe 11 under the action of the suction pump 8, and the outside of the membrane component 4 is flushed through the backwashing device 14; the gas in the gas collecting device 21 reaches the bottom of the membrane component 4 through the first exhaust pipe 23, the second exhaust pipe 24 and the backwashing air inlet pipe 19 through the action of the gas circulation pump 20, and the outside of the membrane component 4 is backwashed by gas through the circulating air inlet device 15.

[0060] Specifically, the domesticated anaerobic sludge is first inoculated into the reactor; it is mixed with ship domestic sewage, ship bilge oily sewage and ship exhaust gas washing waste liquid under the action of a mixer, and water is continuously added with an HRT of 24h and intermittent stirring. During the rotation of the roller brush type flexible filler, some functional bacteria are fixed on it to form a biofilm, and oil degradation reaction, hydrolysis and acidification reaction, sulfate reduction reaction, autotrophic denitrification and heterotrophic denitrification reaction occur in the reactor; large molecular organic matter such as oil in the mixed sewage of ships is degraded into CO2 and water under the joint action of acid-producing bacteria, fermentation bacteria and sulfate-reducing bacteria, and SO4 2- Restore to S 2-, producing hydrogen sulfide gas and nitrogen, which rise to the exhaust hole and enter the gas collection device; the gas generated during the treatment process is discharged from the exhaust hole and enters the gas collection device through the gas collection pipeline; the hydrocarbon substances that are not completely degraded in the oily wastewater, as well as the organic pollutants such as proteins, lipids and sugars brought by domestic sewage, provide carbon sources for the sulfate reduction reaction, promoting SO4 2- reduction, and at the same time these organics are deeply treated; S 2- It provides electron donors for autotrophic denitrifying bacteria, and the remaining undegraded organic matter in the sewage serves as a substrate for heterotrophic denitrifying bacteria. It also desulfurizes and denitrifies the ship's exhaust gas scrubbing liquid, using waste to treat waste, thus avoiding secondary pollution caused by the addition of external carbon sources.

[0061] The treated sewage is filtered through the membrane module and enters the water collection tank through the outlet pipe under the action of the suction pump. The hydrogen sulfide and other gases generated in the reactor enter the gas collection device through the exhaust hole and the gas collection pipeline. The membrane module is backwashed while the pump is stopped. The effluent is returned to the inside of the membrane module through the backwash inlet pipe by the water pump. The gas reaches the bottom of the membrane module through the backwash inlet pipe through the gas peristaltic pump and is backwashed through the circulating air inlet device. When the pressure sensor monitors that the transmembrane pressure difference reaches the set value, the suction pump is used to send the effluent or clean water through the backwash pipe to perform external online flushing of the membrane module.

[0062] In this embodiment, stirring is performed intermittently, the operating temperature is 25-35°C, and the hydraulic retention time in the reaction zone is 10h-48h;

[0063] The sludge acclimation method uses a hydraulic retention time of 24 hours, and the influent components include peptone, sodium bicarbonate, emulsified diesel, sodium sulfide, and sodium nitrate. The activated sludge used for inoculation is obtained from anaerobic sludge tanks or fermentation tanks. Natural seawater is used for dissolution, creating a high-salinity environment that promotes the rapid formation of high-salinity-tolerant microbial flora, facilitating the efficient operation of the desulfurization and denitrification process under high-load, high-salinity conditions. Furthermore, sludge acclimation can be carried out onshore in advance, and the successfully acclimated activated sludge is directly inoculated into the vessel's reactor, significantly shortening the start-up time of the vessel's equipment. This method is suitable for the vessel's operating environment and does not occupy limited space resources on board.

[0064] In a specific embodiment, when the transmembrane pressure difference monitored by the first pressure sensor 7 is 30-40 KPa, the suction pump 8 is started to perform liquid backwashing on the outside of the membrane assembly 4 .

[0065] In a specific embodiment, intermittent reflux is used to perform backwashing inside the membrane assembly 4 , and the time when the membrane assembly 4 is stopped is consistent with the time when the suction pump 8 performs backwashing operation inside the membrane assembly 4 .

[0066] The membrane module filtration and backwashing share a suction pump, and the time when the membrane module is stopped is consistent with the time when the suction pump performs backwashing operation.

[0067] The pumping time of the membrane component is 8 minutes, the stopping time is 1 minute, and the backwashing time is 1 minute. In this scheme, the filtration time of the membrane component is consistent with the backwashing operation time, and the membrane component can be cleaned at the same time as the filtration of the membrane component is completed, thereby improving the efficiency of sewage treatment.

[0068] The overall processing process of this device is as follows:

[0069] (1) Acclimation of activated sludge

[0070] Anaerobic sludge was inoculated from the secondary sedimentation tank of a municipal wastewater treatment plant, with a MLVSS concentration of 14-15 g / L. The inoculated sludge was then inoculated into a continuously stirred reactor (CSBR). Seawater containing organic matter was introduced and allowed to stand for 15 days, with the initial stirring performed simultaneously with the water change. After 15 days, three types of wastewater were added to the sludge: ship oily wastewater (212 mg / L oil and an appropriate amount of sodium bicarbonate); ship domestic wastewater (1.2 g / L peptone and an appropriate amount of sodium bicarbonate); and ship exhaust gas scrubber wastewater (0.17 g / L peptone, 0.93 g / L sodium nitrate, 3.33 g / L sodium sulfide, and an appropriate amount of sodium bicarbonate). The overall pH was between 7.4 and 8.0. The activated sludge was dissolved in natural seawater with an initial HRT of 48 hours, which was then increased to 24 hours after treatment stabilized. Successful acclimation was indicated by an oil removal rate exceeding 90%, a sulfate removal rate exceeding 60%, and a nitrate removal rate exceeding 90% for the mixed wastewater. Seawater contains a large amount of sulfate, and this method only needs to remove the sulfate generated by flue gas scrubbing. Therefore, the sulfate removal rate of sulfate-reducing activated sludge is more than 60%, indicating successful acclimation.

[0071] (2) Device startup

[0072] The acclimated activated sludge was inoculated into the reactor, and a mixture of three types of ship sewage was introduced into the bottom of the shell. The operating temperature was 25-35°C, stirring was continuous, and the stirring speed was 150rpm. Intermittent water inlet was initially used, and continuous water inlet was switched after the reactor operation stabilized. The hydraulic retention time was 24h. The membrane assembly was backwashed while the membrane assembly was being filtered, that is, filtration for 8 minutes and backwashing for 1 minute.

[0073] (3) Device operation

[0074] Hydrolysis and acidification, oil degradation, sulfate reduction, autotrophic denitrification, and heterotrophic denitrification reactions occur within the reactor. Microorganisms in mixed ship wastewater degrade macromolecules such as oil into small hydrocarbons, CO2, and water. Sulfate-reducing bacteria reduce sulfate to sulfide. The resulting sulfide and nitrate in the wash water are ultimately converted into elemental sulfur and nitrogen. The effluent pumping and backwashing cycles coincide with the backwashing cycle: 8 minutes / 1 minute, meaning 8 minutes of pumping and 1 minute of backwashing. Simultaneously, when the pressure sensor detects a transmembrane pressure differential of 30-40 kPa, the valve is opened to backwash the membrane module for 5 minutes. Autotrophic desulfurization and denitrification bacteria thrive in suspended sludge, while heterotrophic desulfurization and denitrification bacteria coexist on the biofilm of the roller brush frame packing. Oil-degrading and acidifying bacteria thrive on the MBR biofilm, achieving spatial separation of the functional bacteria and facilitating the performance of their respective degradation functions.

[0075] The final removal effect is as follows Figure 7 As shown, the oil removal rate can reach more than 99%, the TOC removal rate can reach more than 93%, and the SO4 2- The removal rate can reach more than 62%, NO3 - The removal rate can reach over 90%.

[0076] The beneficial effects of the device and method provided by the present invention are as follows:

[0077] The present invention adopts AnMBR technology to synergistically treat multiple types of ship wastewater, promote the coupling effect of various reactions, maintain a longer sludge retention time, and increase the concentration of microorganisms in the system, thereby facilitating the improvement of the overall treatment efficiency of the reaction device and reducing the generation of excess sludge.

[0078] 2. The addition of frame-type flexible filler can fix the functional bacterial community, prevent the loss of bacterial species, and is not easily disturbed by the external environment during the water treatment process, so that autotrophic bacteria can grow better in suspended sludge and heterotrophic bacteria can attach to the biofilm, reducing the competition among multiple colonies on the same attachment body.

[0079] 3. The sludge can be domesticated in advance to solve the problems of long startup cycle of biochemical treatment and inhibition of microbial activity by high-salt organic wastewater.

[0080] 4. The gas internal circulation system of the device can achieve zero H2S emission, effectively promote the desulfurization and denitrification, and realize the resource reuse of sulfur. The use of annular membrane components, roller brush frame fillers and mixers can increase membrane flux. The hydraulic cross-flow flushing of the membrane components can reduce membrane pollution. The internal and external backwashing devices of the membrane components can also effectively reduce membrane pollution.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An AnMBR in-situ treatment device for ship oily mixed wastewater, characterized in that: include: A reactor shell (1), wherein the reactor shell (1) is provided with an injection port (12), a mud discharge port (28), a backwash device (14), a gas collecting device (21), a gas three-way valve (26), and a third exhaust pipeline (27). and a circulating air inlet device (15); the sample inlet (12) and the mud discharge port (28) are connected to the bottom of the reactor shell (1); a membrane assembly (4) is provided in the reactor shell (1), a stirrer (5) is provided in the membrane assembly (4), and a roller brush frame flexible filler (3) is provided inside and outside the membrane assembly (4); a flexible filler frame (29) is provided on both inside and outside the membrane assembly (4), the roller brush frame flexible filler (3) is provided on the flexible filler frame (29), and the flexible filler frame (29) is connected to the stirrer connecting rod (30) at the upper end of the stirrer (5), and the stirrer (5) rotates, driving the flexible filler frame (29) and the roller brush frame flexible filler (3) to rotate, thereby performing roller brush friction cleaning on the outside of the membrane assembly (4); A suction pipe (6) is provided in the reactor shell (1), and the treated sewage is discharged to an external water collection tank through the suction pipe (6), the suction pump (8), the liquid three-way valve (9) and the outlet pipe (10). The liquid is sucked from the water collection tank by the suction pump (8) and enters the reactor shell (1) through the backwash inlet pipe (11) and the backwash device (14) to wash the outside of the membrane assembly (4); The reactor shell (1) is provided with an air outlet (2) at the top thereof, and the treated gas is discharged from the air outlet (2) through the gas collecting pipeline (22), the first exhaust pipeline (23), the second exhaust pipeline (24) and the backwashing air inlet pipeline (19), and is pumped into the reactor shell (1) through the circulating air inlet device (15) under the action of the gas circulation pump (20) to flush the membrane assembly (4); One end of the gas collecting device (21) is connected to the gas outlet (2) via the gas collecting pipeline (22); the other end of the gas collecting device (21) is connected to one end of the gas three-way valve (26) via the first exhaust pipeline (23); the other end of the gas three-way valve (26) is connected to one end of the third exhaust pipeline (27), and the other end of the third exhaust pipeline (27) is connected to an external collection device.

2. The AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1, characterized in that: It also includes a sampling port (13), which is connected to the reactor shell (1).

3. The AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1, characterized in that: Also includes a first pressure sensor (7) and a second pressure sensor (25); The first pressure sensor (7) is provided on the suction pipeline (6) to monitor the transmembrane pressure difference, and the second pressure sensor (25) is provided on the gas collecting device (21) to monitor the pressure inside the gas collecting device (21).

4. The AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1, characterized in that: The mixer (5) comprises a first stirring paddle (16), a second stirring paddle (17) and a third stirring paddle (18).

5. A method for in-situ treatment of ship oily mixed wastewater using AnMBR in-situ treatment device for ship oily mixed wastewater according to any one of claims 1 to 4, characterized in that: include: S1: The acclimated anaerobic sludge is inoculated into the reactor, and the ship's oily sewage, ship's domestic sewage and ship's exhaust gas scrubbing liquid enter the reactor through the inlet (12); S2: Ship oily sewage, ship domestic sewage and ship exhaust gas washing liquid enter the reactor through the sampling port (12), and are mixed with anaerobic sludge under the action of the mixer (5), and undergo hydrolysis and acidification reaction, oil degradation reaction, sulfate reduction reaction and autotrophic / heterotrophic denitrification reaction. The generated gas is discharged from the gas outlet (2) and enters the gas collecting device (21) through the gas collecting pipeline (22); S3: The treated sewage is filtered by the membrane assembly (4), passes through the suction pipe (6) and the liquid three-way valve (9), and enters the external water collection tank through the outlet pipe (10) under the action of the suction pump (8). After the membrane assembly (4) is filtered, the suction pump (8) is started to backwash the inside of the membrane assembly (4). When the first pressure sensor (7) reaches the set pressure value, the valve connected to the liquid three-way valve (9) and the backwashing water inlet pipe (11) is opened. The treated sewage flows back to the bottom of the membrane assembly (4) through the backwashing water inlet pipe (11) under the action of the suction pump (8), and the outside of the membrane assembly (4) is flushed through the backwashing device (14); the gas in the gas collecting device (21) reaches the bottom of the membrane assembly (4) through the first exhaust pipe (23), the second exhaust pipe (24) and the backwashing air inlet pipe (19) under the action of the gas circulation pump (20), and the outside of the membrane assembly (4) is backwashed by gas through the circulating air inlet device (15).

6. The AnMBR in-situ treatment method for ship oily mixed wastewater according to claim 5, characterized in that: When the transmembrane pressure difference monitored by the first pressure sensor (7) is 30-40 KPa, the suction pump (8) is started to perform liquid backwashing on the outside of the membrane assembly (4).

7. The AnMBR in-situ treatment method for ship oily mixed wastewater according to claim 5, characterized in that: The membrane assembly (4) is backwashed internally by an intermittent reflux method, and the time when the membrane assembly (4) is pumped and stopped is consistent with the time when the suction pump (8) performs the backwashing operation inside the membrane assembly (4).

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