AnMBR in-situ treatment device and method for marine oil-containing mixed wastewater

Abstract

The invention discloses an AnMBR in-situ treatment device and method for marine oil-containing mixed wastewater. The AnMBR in-situ treatment device comprises a reactor shell, and the shell is provided with a sample inlet, a sludge outlet, a backwashing device and a circulating gas inlet device; a membrane component is arranged in the shell, a stirrer is arranged in the membrane component, and rolling brush type frame flexible filler is arranged inside and outside the membrane component; a suction pipeline is arranged in the shell, treated sewage is discharged to an external water collecting tank through the suction pipeline, a suction pump, a liquid three-way valve and a water outlet pipe, and liquid is sucked from the water collecting tank through the suction pump and enters the reactor shell through a backwashing water inlet pipe and a backwashing device to wash the outside of the membrane module; a gas outlet hole is formed in the top of the reactor shell, and treated gas is exhausted from the gas outlet hole, passes through a gas collecting pipeline, a first gas exhaust pipeline, a second gas exhaust pipeline and a backwashing gas inlet pipeline, is pumped into the reactor shell through a circulating gas inlet device under the action of a gas circulating pump and is used for washing the membrane component; according to the invention, the contradiction between small ship space and large complex occupied area of the treatment device can be solved, the accumulation of pollutants in the membrane module is slowed down, the operation cost is reduced, the microbial density is increased, the spatial distribution of functional bacteria is completed, the impact resistance of the device is improved, and the comprehensive in-situ removal of carbon, nitrogen and sulfur pollutants and the zero emission of harmful gases are realized.

Description

Technical Field

[0001] The 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 increased day by day, and marine environmental protection is facing severe challenges. According to the "International Convention for the Prevention of Pollution from Ships (MARPOL73 / 78)" of the Marine Environment Protection Committee of the International Maritime Organization and my country's "Ship Water Pollutant Emission Control Standard" (GB3552-2018), ships' domestic sewage must be strictly pre-treated before discharge to prevent excessive organic matter from being discharged into the sea. Large amounts of SO2 are emitted by ship diesel engines. X and NO X After wet treatment, it will be SO4 2- and NO3 - In the form of waste gas scrubbers, a large amount of oily wastewater from the bilge will accumulate at the bottom of long-distance ships, which contains a variety of hydrocarbon pollutants with complex components. According to relevant requirements, these wastewaters cannot be discharged in a disorderly manner.

[0003] The large navigation volume and high density of crew members on ships make the concentration of pollutants in ship wastewater usually 2 to 3 times that on land; the space on the hull is limited, and the treatment equipment cannot be too large or too high; the temperature difference caused by long-term navigation, hull vibration and tilt are not conducive to the stability of microbial treatment efficiency; the residual sludge on board is difficult to dispose; the sewage contains a large amount of salts and other substances. The above series of problems increase the difficulty of ship wastewater treatment, making the efficient in-situ treatment of ship mixed wastewater a huge challenge.

[0004] Membrane bioreactor (MBR) technology has the advantages of high mud-effluent separation efficiency, small footprint, and easy regulation of hydraulic retention time (HRT) and sludge retention time (SRT). Currently, aerobic MBR has been widely used in ship sewage treatment. Compared with aerobic MBR, anaerobic membrane bioreactor (AnMBR) has the advantages of low energy consumption, low sludge production, and easy treatment of complex organic matter. However, the AnMBR process still faces some challenges, mainly including: 1) Limited space on ships, it is difficult to deal with a large number of wastewaters; 2) It is difficult to colonize bacteria in the treatment of high-salinity organic wastewater, and it is easy to lose, and it is impossible to maintain a high sludge concentration; 3) The membrane fouling problem is serious, and the membrane components need to be replaced frequently, resulting in high treatment costs and low efficiency; 4) Microorganisms are easily disturbed by the external environment. Therefore, it is urgent to propose innovative technical solutions to overcome the above difficulties and promote the progress of ship integrated sewage in situ treatment methods. 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 pollution, 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 in that it comprises: a reactor shell, on which a sample inlet, a mud outlet, a backwashing device and a circulating air intake device are provided; the sample inlet and the mud outlet are connected to the bottom of the reactor shell; a stirrer is provided in the membrane module, and a rolling brush frame flexible filler is provided inside and outside the membrane module;

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

[0009] An air outlet is provided on 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 reactor shell through the circulating air inlet device to flush the membrane assembly.

[0010] Furthermore, a flexible packing frame is provided on both sides inside and outside the membrane assembly, the roller brush type frame flexible packing is arranged 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 an external collection device.

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

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

[0015] The first pressure sensor is arranged on the suction pipeline to monitor the transmembrane pressure difference, and the second pressure sensor is arranged 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 in-situ treatment method for ship oily mixed wastewater AnMBR based on the in-situ treatment device for ship oily mixed wastewater according to claim 1, comprising:

[0018] S1: The domesticated 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 washing liquid enter the reactor through the inlet, and are mixed with anaerobic sludge under the action of the mixer, and hydrolysis acidification reaction, oil degradation reaction, sulfate reduction reaction and autotrophic / heterotrophic denitrification reaction occur. The generated gas is discharged from the gas outlet and enters the gas collecting device through the gas collecting pipeline;

[0020] S3: The treated sewage is filtered through the membrane assembly, through the suction pipeline 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 pipeline, the second exhaust pipeline and the backwashing air inlet pipeline 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 fix the functional bacteria and separate them in space. The water shear force generated by the frame rotation and 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 ship and the complex and large area occupied by the treatment device;

[0026] 3. There is a gas outlet connected to the gas collecting device, and the gas generated by the reaction can be circulated to flush the membrane components to achieve resource recycling of the gas;

[0027] 4. The treated water and gas are set in different pipelines, and the membrane components can be backwashed separately, which reduces the operating cost, prevents membrane pollution, and extends 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 briefly introduces 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 creative work.

[0029] Figure 1 The structural diagram of the AnMBR in-situ treatment device for oily mixed wastewater from ships provided by the present invention;

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

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

[0032] Figure 4 The structural diagram of the membrane assembly of the AnMBR in-situ treatment device for oily mixed wastewater from ships 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 oily mixed wastewater from ships provided by the present invention;

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

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

[0036] In the figure, 1, reactor shell; 2, air outlet; 3, roller brush frame suspended flexible filler; 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 filler frame; 30, mixer connecting rod. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] This embodiment provides an AnMBR in-situ treatment device for oily mixed wastewater from ships, such as Figure 1 As shown, it comprises: a reactor shell 1, on which a sample inlet 12, a mud discharge port 28, a backwashing device 14 and a circulating air intake 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 rolling brush frame flexible filler 3 is provided inside and outside the membrane assembly 4;

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

[0040] An air outlet 2 is provided on 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, the gas is pumped into 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 a sample inlet, a mud outlet, a backwashing device and a circulating air intake device are arranged at the bottom of the reactor shell, the sample inlet and the mud outlet are arranged on both sides of the bottom of the reactor, and the backwashing device and the circulating air intake device are arranged at the center of the bottom of the reactor;

[0042] A brush-type frame biological filler and a ring-type membrane assembly are arranged inside the reactor, a stirrer is arranged inside the membrane assembly, and an air outlet is arranged on the upper part of the reactor, which 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 a gas circulation pipeline under the action of a gas circulation pump, and the treated sewage passes through a suction pump, and the water outlet from the pumping pipeline flows into an 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 a backwashing inlet pipe and a backwashing device to wash the outside of the membrane assembly.

[0043] In the specific implementation, Figure 2 and Figure 3 As shown, a flexible packing frame 29 is provided on both sides inside and outside 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 30 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 in FIG. 1 , a cross-shaped mixer connecting rod is provided at the top of the mixer, such as Figure 3 As shown, the membrane assembly is a ring-shaped 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 agitator 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 agitator rotates, driving the flexible packing frame connected to it and the roller brush frame flexible packing wrapped around the flexible packing frame to rotate, thereby 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, heterotrophic bacteria can attach to the biofilm, and reduce the competition of multiple colonies on the same attachment.

[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 pipeline 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 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 collecting 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 recovery and reuse of sulfur.

[0049] In a specific embodiment, Figure 1 As shown, it also includes a sampling port 13, and the sampling port 13 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 disposed on the suction pipeline 6 to monitor the transmembrane pressure difference, and the second pressure sensor 25 is disposed 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 trans-membrane 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] Three stirring paddles are set in the mixer, which are used in conjunction with the ring-type membrane components and roller brush frame fillers to increase membrane flux, and hydraulic cross-flow flushing of the membrane components can reduce membrane pollution.

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

[0057] S1: The domesticated anaerobic sludge is inoculated into the reactor, and the ship oily sewage, ship domestic sewage and ship exhaust gas washing 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, and hydrolysis acidification reaction, oil degradation reaction, sulfate reduction reaction and autotrophic / heterotrophic denitrification reaction occur, and the generated gas is discharged from the gas outlet 2 and enters the gas collecting device 21 through the gas collecting pipeline 22;

[0059] S3: The treated sewage is filtered by the membrane assembly 4, through the suction pipeline 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 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 pipeline 23, the second exhaust pipeline 24 and the backwashing air inlet pipeline 19 through 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.

[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 introduced 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, while SO4 2- Restore to S 2-, generating 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 and promote SO4 2- reduction, and at the same time these organic matters are deeply treated; S 2- It provides electron donors for autotrophic denitrifying bacteria, and the remaining undegraded organic matter in the sewage supplements the substrate for heterotrophic denitrifying bacteria. It desulfurizes and denitrifies the ship exhaust gas washing liquid, and uses waste to treat waste, avoiding secondary pollution caused by the addition of external carbon sources.

[0061] The treated sewage is filtered through the membrane assembly through the outlet pipe and enters the water collecting tank under the action of the suction pump. The hydrogen sulfide and other gases generated in the reactor enter the gas collecting device through the exhaust hole and the gas collecting pipeline. The membrane assembly is backwashed while the pumping is stopped. The outlet water is refluxed to the inside of the membrane assembly through the backwashing water inlet pipe by the water pump. The gas reaches the bottom of the membrane assembly through the backwashing air 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 outlet water or clean water is used by the suction pump to perform external online flushing of the membrane assembly through the backwashing pipe.

[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 is as follows: the hydraulic retention time is 24h, the influent components are peptone, sodium bicarbonate, emulsified diesel, sodium sulfide, and sodium nitrate; the inoculated activated sludge is taken from the anaerobic sludge pool or fermentation tank; natural seawater is used for dissolution to create a high-salt environment, promote the rapid formation of high-salt-tolerant microbial flora, and facilitate the efficient operation of the desulfurization and denitrification process under high-load and high-salt conditions. At the same time, sludge acclimation can be carried out in advance on land, and the successfully acclimated activated sludge is directly inoculated into the reaction device on the ship, which greatly shortens the start-up time of the ship's device, is suitable for the ship's operating environment, and does not need to occupy the limited space resources on the ship.

[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, an intermittent reflux method 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 assembly filtration and backwashing share a suction pump, and the time when the membrane assembly 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) Domestication of activated sludge

[0070] Anaerobic sludge was inoculated from the secondary sedimentation tank of the municipal sewage plant, and the suspended solid concentration (MLVSS) of the inoculated sludge was 14-15g / L. It was inoculated into a continuous stirred reactor, and seawater containing organic matter was introduced and left to stand for 15 days. The first stirring was carried out while the water was changed. After 15 days, three types of wastewater were added to the sewage. The components of ship oily sewage were: oil 212mg / L, appropriate amount of sodium bicarbonate; the components of ship domestic sewage were peptone 1.2g / L, appropriate amount of sodium bicarbonate; the components of ship exhaust gas washing waste liquid were: peptone 0.17g / L, sodium nitrate 0.93g / L, sodium sulfide 3.33g / L, appropriate amount of sodium bicarbonate, where the overall pH was between 7.4-8.0, and natural seawater was used for dissolution. The HRT was first 48h, and then changed to 24h after the treatment effect was stable. The oil removal rate of the activated sludge treating mixed sewage was more than 90%, the sulfate removal rate was more than 60%, and the nitrate removal rate was more than 90%, indicating successful domestication. 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 domestication.

[0071] (2) Device startup

[0072] The domesticated activated sludge was inoculated into the reactor, and the mixed wastewater of three types of ship sewage was introduced into the bottom of the shell. The operating temperature was 25-35℃, stirring was continuous, and the stirring speed was 150rpm. Intermittent water inlet was used at the beginning, and continuous water inlet was switched after the reactor operation was stable. The hydraulic retention time was 24h. The membrane assembly was filtered and the inside of the membrane assembly was backwashed at the same time, that is, filtration for 8min and backwashing for 1min.

[0073] (3) Device operation

[0074] Hydrolysis and acidification reaction, oil degradation reaction, sulfate reduction reaction, autotrophic denitrification and heterotrophic denitrification reaction occur in the reactor. Under the action of microorganisms, the mixed sewage of ships degrades macromolecules such as oil into small molecular hydrocarbons, CO2 and water. Under the action of sulfate-reducing bacteria, sulfate is reduced to sulfide; the generated sulfide and nitrate in the washing wastewater are finally converted into elemental sulfur and nitrogen. The pumping and stopping time of the effluent is consistent with the backwashing time, and the pumping / stopping time is 8min / 1min, that is, 8min of filtration and 1min of backwashing; at the same time, when the pressure sensor monitors the transmembrane pressure difference at 30-40Kpa, open the valve and backwash the outside of the membrane assembly for 5min through the backwashing device. Autotrophic desulfurization and denitrification bacteria are suitable for growth in suspended sludge, heterotrophic desulfurization and denitrification bacteria and sulfate-reducing bacteria are suitable for coexistence on the biofilm of the roller brush frame filler, and oil degradation bacteria and acidification bacteria are suitable for survival on the MBR biofilm, thereby realizing the spatial separation of functional bacteria and facilitating the performance of various 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 various wastewaters from ships, promote the coupling effect of various reactions, maintain a long 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 flora, 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.

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

[0080] 4. The gas internal circulation system of the device can achieve zero emission of H2S, and effectively promote the desulfurization and denitrification, and realize the resource reuse of sulfur. The use of annular membrane components, roller brush frame fillers and agitators can increase membrane flux. Hydraulic cross-flow flushing of 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned 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 oily mixed wastewater from ships, 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 backwashing device (14) and a circulating air intake device (15); the injection port (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 rolling brush frame flexible fillers (3) are provided inside and outside the membrane assembly (4); A suction pipeline (6) is provided in the reactor shell (1), and the treated sewage is discharged to an external water collection tank through the suction pipeline (6), a suction pump (8), a liquid three-way valve (9) and a water outlet pipe (10). Liquid is then sucked from the water collection tank by the suction pump (8) and enters the reactor shell (1) through the backwashing water inlet pipe (11) and the backwashing device (14) to wash the outside of the membrane module (4); The reactor shell (1) is provided with an air outlet (2) at the top, and the treated gas is discharged from the air outlet (2) through a gas collecting pipeline (22), a first exhaust pipeline (23), a second exhaust pipeline (24) and a backwashing air inlet pipeline (19), and under the action of a gas circulation pump (20), is pumped into the reactor shell (1) through the circulating air inlet device (15) to flush the membrane assembly (4).

2. The AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1 is characterized in that: Flexible packing frames (29) are provided on both sides of the membrane assembly (4), and the roller brush frame flexible packing (3) is provided on the flexible packing frame (29). The flexible packing frame (29) is connected to the mixer connecting rod (30) at the upper end of the mixer (5). When the mixer (5) rotates, the flexible packing frame (30) and the roller brush frame flexible packing (3) are driven to rotate, so as to perform roller brush friction cleaning on the outside of the membrane assembly (4).

3. The AnMBR in-situ treatment device for ship oily mixed wastewater according to claim 1 is characterized in that: It also includes a gas collecting device (21), a gas three-way valve (26) and a third exhaust pipeline (27): 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 collecting device.

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

5. 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 arranged on the suction pipeline (6) to monitor the transmembrane pressure difference, and the second pressure sensor (25) is arranged on the gas collecting device (21) to monitor the pressure inside the gas collecting device (21).

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

7. An in-situ treatment method for ship oily mixed wastewater AnMBR based on the in-situ treatment device for ship oily mixed wastewater according to any one of claims 1 to 6, characterized in that: include: S1: inoculating the domesticated anaerobic sludge into the reactor, and the ship's oily sewage, ship's domestic sewage and ship's exhaust gas washing 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 hydrolysis and acidification reaction, oil degradation reaction, sulfate reduction reaction and autotrophic / heterotrophic denitrification reaction occur, and 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), through the suction pipeline (6) and the liquid three-way valve (9), and under the action of the suction pump (8), enters the external water collection tank through the outlet pipe (10). 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 a set pressure value, the valve connected to the liquid three-way valve (9) and the backwashing water inlet pipe (11) is opened. Under the action of the suction pump (8), the treated sewage flows back to the bottom of the membrane assembly (4) through the backwashing water inlet pipe (11), 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 pipeline (23), the second exhaust pipeline (24) and the backwashing air inlet pipeline (19) through 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).

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

9. The AnMBR in-situ treatment method for ship oily mixed wastewater according to claim 7 is characterized in that: An intermittent reflux method is used to perform internal backwashing of the membrane assembly (4), and the time when the membrane assembly (4) is pumped and stopped is consistent with the time when the suction pump (8) performs internal backwashing operation of the membrane assembly (4).

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