Marine multi-stage anaerobic MBR device and ship multi-source sewage cooperative treatment method

Abstract

The invention discloses a marine multi-stage anaerobic MBR device and a marine multi-source sewage cooperative treatment method, and the marine multi-stage anaerobic MBR device comprises: a reactor shell provided with sample inlets I, II and III; an anaerobic chamber I, an anaerobic chamber II and an anaerobic chamber III which are communicated in sequence are arranged in the shell; the sample inlet I is communicated with the anaerobic chamber I, the sample inlet II is communicated with the anaerobic chamber II, and the sample inlet III is communicated with the anaerobic chamber III; stirrers are arranged in the three anaerobic chambers, a membrane assembly and a spiral-flow type water distributor are arranged in the anaerobic chamber III, and a water outlet is formed in the bottom of the anaerobic chamber III; a baffle plate and a baffle plate vertical plate are arranged on two sides of the anaerobic chamber II; the treated sewage flows out from a water outlet and flows into an anaerobic chamber III from a backwashing water inlet pipe; exhaust holes are formed in the top ends of the three anaerobic chambers, and treated gas is exhausted from the exhaust holes and enters the anaerobic chamber III from a backwashing gas inlet pipeline; according to the device, pipelines are respectively arranged for treated water and gas, the solubility of sulfide is enhanced while the membrane component is backwashed, the operation cost is reduced, membrane pollution is strictly prevented, integrated ship sewage treatment equipment is provided, and the cost is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and particularly relates to a marine multi-stage anaerobic MBR device and a method for synergistically treating multi-source sewage of ships. Background Art

[0002] Wastewater is no longer regarded as a pollution source, but rather as a renewable resource with the potential for clean recycled water, effective nutrient, and renewable energy recovery. The resources extracted through sewage treatment can effectively offset the operating costs during the treatment process and are highly competitive. A large amount of harmful substances such as excreted organic matter and emulsified oil are contained in ship organic wastewater (including domestic sewage and bilge sewage), while a large amount of inorganic pollutants such as sulfates and nitrates are contained in ship exhaust gas scrubbing liquid. These substances can be recycled through appropriate in-situ treatment technologies on ships to turn waste into resources.

[0003] At present, the membrane bioreactor (MBR) has advantages such as simple operation and small floor area, which is conducive to improving the water treatment efficiency and has been used for the treatment of ship domestic sewage. The traditional wastewater MBR process has difficulty in dealing with complex and diverse comprehensive wastewater treatment, and the in-situ treatment technology for ships is even more difficult. Therefore, there is an urgent need to develop a marine sewage in-situ treatment device with high efficiency, stable operation, and small volume to meet the increasingly stringent requirements of ship navigation. Summary of the Invention

[0004] The present invention provides a marine multi-stage anaerobic MBR device and a method for synergistically treating multi-source sewage of ships to overcome the problems that the traditional marine MBR needs to be frequently membrane-cleaned, has complex operation, resulting in high energy consumption, high cost, and low efficiency, and can also address the technical problems of insufficient backwashing gas volume and insufficient carbon source.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A marine multi-stage anaerobic MBR device includes: a reactor housing, and a sample inlet Ⅰ, a sample inlet Ⅱ, and a sample inlet Ⅲ are provided on the reactor housing;

[0007] An anaerobic chamber Ⅰ, an anaerobic chamber Ⅱ, and an anaerobic chamber Ⅲ are successively connected and communicated inside the reactor housing; the sample inlet Ⅰ is communicated with the anaerobic chamber Ⅰ, the sample inlet Ⅱ is communicated with the anaerobic chamber Ⅱ, and the sample inlet Ⅲ is communicated with the anaerobic chamber Ⅲ; stirrers are provided inside the anaerobic chamber Ⅰ, the anaerobic chamber Ⅱ, and the anaerobic chamber Ⅲ, and a membrane module and a swirl water distributor are further provided inside the anaerobic chamber Ⅲ; baffle plates and baffle vertical plates are provided on both sides of the anaerobic chamber Ⅱ; a drain port is further provided on the anaerobic chamber Ⅲ; the treated sewage flows out from the drain port, passes through a suction pipeline, a suction pump, and a backwash water inlet pipe, and then flows into the anaerobic chamber Ⅲ;

[0008] The anaerobic chamber I, anaerobic chamber II, and anaerobic chamber III are all provided with exhaust holes at the top. The treated gas is discharged from the exhaust holes and enters anaerobic chamber III through the gas collection pipeline, gas circulation pipeline, gas peristaltic pump, and backwashing intake pipeline.

[0009] Furthermore, it also includes a gas collection device and a gas three-way valve. One end of the gas collection device is connected to the gas collection pipeline through the gas three-way valve. The other end of the gas collection device is connected to one end of the gas circulation pipeline. The other end of the gas circulation pipeline is connected to the backwashing intake pipeline through the gas peristaltic pump.

[0010] Furthermore, it also includes a water outlet pipe and a pressure sensor. The water outlet pipe is externally connected to a collection water tank. The pressure sensor is arranged on the suction pipeline. The treated sewage enters the collection water tank through the liquid three-way valve and the water outlet pipe. The suction pump sucks the liquid from the collection water tank through the water outlet pipe, passes through the liquid three-way valve and the backwashing intake pipe, and flows into anaerobic chamber III.

[0011] Furthermore, the mixer includes a first mixing paddle and a second mixing paddle.

[0012] Furthermore, overflow weirs are provided at the upper parts of the anaerobic chamber I and anaerobic chamber II. The anaerobic chamber I communicates with the baffle plate and the vertical baffle plate through the overflow weir. The lower part of the baffle plate communicates with the anaerobic chamber II and anaerobic chamber III in sequence.

[0013] A method for collaborative treatment of multi-source sewage on ships includes:

[0014] S1: Inoculate the domesticated anaerobic oil-removing sludge into anaerobic chamber I, sulfate-reducing sludge into anaerobic chamber II, and desulfurizing denitrifying sludge into anaerobic chamber III. The oily sewage from ships enters anaerobic chamber I through the sampling port I, the domestic sewage from ships enters anaerobic chamber II through the sampling port II, and the waste gas washing liquid from ships enters anaerobic chamber III through the sampling port III.

[0015] S2: The oily sewage from ships enters anaerobic chamber I through the sampling port I. Under the action of the mixer, it is mixed with the anaerobic oil-removing sludge, and hydrolysis acidification reaction, oil degradation reaction, and sulfate reduction reaction occur. The treated oily sewage from ships overflows into anaerobic chamber II through the vertical baffle plate and the baffle plate between anaerobic chamber I and anaerobic chamber II. The generated gas is discharged from the exhaust hole and enters the gas collection device through the gas collection pipeline and the gas three-way valve.

[0016] S3: The ship's domestic sewage enters anaerobic chamber II through sampling port II, and is mixed with the treated ship's oily sewage and sulfate-reducing sludge under the action of a stirrer, and a sulfate reduction reaction occurs. The treated ship's domestic sewage and the secondary-treated ship's oily sewage overflow into anaerobic chamber III through the vertical plate and baffle of the baffle between anaerobic chamber II and anaerobic chamber III; the generated gas is discharged from the exhaust hole and enters the gas collection device through the gas pipeline and gas three-way valve;

[0017] S4: The ship's exhaust gas washing liquid enters anaerobic chamber III through sampling port III, and is mixed with the treated ship's oily sewage, ship's domestic sewage and desulfurization denitrification sludge under the action of a stirrer, and an autotrophic / heterotrophic denitrification-sulfate reduction coupling reaction occurs. The generated gas is discharged from the exhaust hole and enters the gas collection device through the gas pipeline and gas three-way valve;

[0018] S5: The sewage treated in S4 flows out from the drain port under the suction filtration of the membrane module, passes through the suction pipeline and liquid three-way valve, and enters the collection tank through the water outlet pipe under the action of the suction pump. After the membrane module performs suction filtration, the suction pump is started to perform internal backwashing on the membrane module. When the pressure sensor reaches the set pressure value, the valve of the liquid three-way valve and the backwashing inlet pipe is opened, and the water flows back to the bottom of the membrane module through the backwashing inlet pipe under the action of the suction pump, and the outside of the membrane module is washed through the swirl water distributor; the gas in the gas collection device reaches the bottom of the membrane module through the gas pipeline and gas circulation pipeline under the action of the gas peristaltic pump to wash the outside of the membrane module.

[0019] Further, when the pressure sensor on the suction pipeline is at 30 - 40 Kpa, the suction pump and the gas peristaltic pump are started to perform gas and liquid backwashing on the outside of the membrane module.

[0020] Further, the internal backwashing of the membrane module is carried out in an intermittent reflux manner, and the pumping stop time of the membrane module is the same as the operation time of the suction pump for internal backwashing of the membrane module.

[0021] Beneficial effects: The present invention provides a marine multi-stage anaerobic MBR device, which has the following advantages:

[0022] 1. By setting three anaerobic chambers, the ship's domestic sewage, ship's oily sewage and ship's exhaust gas washing liquid can be synchronously treated in the same integrated device, overcoming the disadvantages of adding external carbon sources in traditional processes, saving energy consumption, reducing the occupation of hull space, and realizing the efficient in-situ synergistic removal of various pollutants under the action of enhanced microorganisms. It has the advantages of high degree of carbon, nitrogen and sulfur resource utilization in sewage, high treatment efficiency, low energy consumption, simple operation and integration;

[0023] 2. Adopt segmented treatment, that is, different sewage is introduced into each reaction chamber respectively. The sewage treated successively in the anaerobic chamber directly enters the third zone of the anaerobic chamber, namely the membrane chamber, through the baffle plate, so as to supplement the degradation substrates required by heterotrophic denitrifying bacteria and autotrophic desulfurizing denitrifying bacteria, improve the effluent effect and achieve the purpose of treating waste with waste;

[0024] 3. Each chamber is provided with an air outlet connected to the gas collecting box to prevent harmful gases from being discharged into the environment. At the same time, it solves the problem of insufficient internal circulation gas in the traditional anaerobic process and can also realize the reuse of hydrogen sulfide gas;

[0025] 4. Different pipelines are set for the treated water and gas, and the membrane module can be backwashed separately, reducing the operation cost, preventing membrane pollution and prolonging the service life of the membrane module. Brief Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0027] Figure 1 It is a structural diagram of a marine multi-stage anaerobic MBR device provided by the present invention;

[0028] Figure 2 It is a method flow chart of a method for collaborative treatment of multi-source sewage on ships provided by the present invention;

[0029] Figure 3 It is a schematic diagram of the oil removal rate and TOC removal rate in the anaerobic chamber I of the device of the present invention;

[0030] Figure 4 It is a schematic diagram of the SO4 2- removal rate and TOC removal rate in the anaerobic chamber II of the device of the present invention;

[0031] Figure 5 It is a schematic diagram of the NO3 - removal rate and TOC removal rate in the anaerobic chamber III of the device of the present invention.

[0032] In the figure, 1 is the reactor shell; 2 is anaerobic chamber I; 3 is anaerobic chamber II; 4 is anaerobic chamber III; 5 is the agitator; 6 is the exhaust hole; 7 is the overflow weir; 8 is the vertical baffle; 9 is the baffle; 10 is the suction pump; 11 is the gas peristaltic pump; 12 is the backwash inlet pipeline; 13 is the gas collection device; 14 is the gas three-way valve; 15 is the gas collection pipeline; 16 is the gas circulation pipeline; 17 is the pressure sensor; 18 is the suction pipeline; 19 is the liquid three-way valve; 20 is the outlet pipe; 21 is the sample inlet I; 22 is the sample inlet II; 23 is the sample inlet III; 24 is the membrane module; 25 is the drain outlet; 26 is the swirling water distributor; 27 is the first stirring paddle; 28 is the second stirring paddle; 29 is the backwash inlet pipe; 30 is the air inlet. Detailed implementation mode

[0033] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0034] This embodiment provides a marine multi-stage anaerobic MBR device, as Figure 1 shown, including: a reactor shell 1, on which there are a sample inlet I 21, a sample inlet II 22 and a sample inlet III 23;

[0035] Inside the reactor shell 1, there are anaerobic chamber I 2, anaerobic chamber II 3 and anaerobic chamber III 4 connected in sequence; the sample inlet I 21 is connected to the anaerobic chamber I 2, the sample inlet II 22 is connected to the anaerobic chamber II 3, and the sample inlet III 23 is connected to the anaerobic chamber III 4; inside the anaerobic chamber I 2, the anaerobic chamber II 3 and the anaerobic chamber III 4, there is an agitator 5, and inside the anaerobic chamber III 4, there are also a membrane module 24 and a swirling water distributor 26; on both sides of the anaerobic chamber II 3, there are baffles 9 and vertical baffles 8; on the anaerobic chamber III 4, there is also a drain outlet 25; the treated sewage flows out from the drain outlet 25, flows through the suction pipeline 18, the suction pump 10 and the backwash inlet pipe 29 and enters the anaerobic chamber III 4;

[0036] At the top of the anaerobic chamber I 2, the anaerobic chamber II 3 and the anaerobic chamber III 4, there are exhaust holes 6, and the treated gas is discharged from the exhaust holes 6 and enters the anaerobic chamber III 4 through the gas collection pipeline 15, the gas circulation pipeline 16, the gas peristaltic pump 11 and the backwash inlet pipeline 12.

[0037] Specifically, the reactor shell is enclosed, with exhaust holes at the top of the three anaerobic chambers, sampling ports at the bottom of each anaerobic chamber, and agitators inside each anaerobic chamber; Anaerobic chamber III is an anaerobic MBR chamber, with a membrane module inside. The membrane module is in a plate structure or a ring structure, composed of one to multiple curtain-shaped membranes. The membrane module is square and has the same shape as the reactor shell. The agitator in anaerobic chamber III is installed inside the membrane module, and a swirl water distributor is provided at the bottom of the membrane module for backwashing the outside of the membrane module; The self-production rate of anaerobic microorganisms is relatively low, and the residues can be removed through microbial metabolism. Therefore, the device does not need to discharge excess sludge. If sludge discharge and maintenance are indeed required, it can be completed through reverse operation of the water inlets 21, 22 and the air inlet 30;

[0038] An overflow weir is provided at the upper part of anaerobic chamber I, which is connected to the baffle plate and the vertical baffle plate. It is sequentially connected to anaerobic chamber II and anaerobic chamber III through the lower part of the baffle plate; The vertical height of the overflow weir is 0.8 cm - 1.5 cm, the inclination angle of the baffle plate is 45° - 60°, and the distance between the baffle plate and the vertical baffle plate is 3 - 5 cm.

[0039] In a specific embodiment, it further includes a gas collection device 13 and a gas three-way valve 14; One end of the gas collection device 13 is connected to the gas collection pipeline 15 through the gas three-way valve 14; The other end of the gas collection device 13 is connected to one end of the gas circulation pipeline 16; The other end of the gas circulation pipeline 16 is connected to the backwashing air inlet pipeline 12 through a gas peristaltic pump 11.

[0040] In this solution, a gas collection device is set up, which can collect various gases generated after sewage treatment. Through the gas peristaltic pump and the gas circulation pipeline, the generated large-flux gas is circulated inside the device, solving the problem of insufficient internal circulation gas in the traditional anaerobic process.

[0041] In a specific embodiment, it further includes a water outlet pipe 20 and a pressure sensor 17. The water outlet pipe 20 is externally connected to a collection tank; The pressure sensor 17 is installed on the suction pipeline 18; The treated sewage enters the collection tank through the liquid three-way valve 19 and the water outlet pipe 20. The suction pump 10 sucks the liquid from the collection tank through the water outlet pipe 20, passes through the liquid three-way valve 19 and the backwashing water inlet pipe 29, and flows into anaerobic chamber III 4.

[0042] The treated sewage flows into the externally connected collection tank through the water outlet pipe, and when backwashing is carried out, water is pumped from the collection tank through the suction pump and the water outlet pipe. The intermittent reflux method is used for internal backwashing of the membrane module. The pumping and stopping time of the membrane module is the same as the operation time of the suction pump for internal backwashing of the membrane module, and internal backwashing of the membrane module is carried out. A pressure sensor is set. When the pressure exceeds the specified value, the backwashing operation is carried out.

[0043] In a specific embodiment, the mixer 5 includes a first mixing paddle 27 and a second mixing paddle 28.

[0044] In this solution, the mixing paddle at the bottom is 5 - 8 cm away from the bottom of the housing, and the distance from the upper mixing paddle is 2 cm - 4 cm; the double - paddle mixing is adopted to enhance the mass transfer ability of the activated sludge, so that the sewage is fully mixed with the microorganisms in the activated sludge, improving the treatment efficiency of the system.

[0045] In a specific embodiment, overflow weirs 7 are provided at the upper parts of both the anaerobic chamber I 2 and the anaerobic chamber II 3. The anaerobic chamber I 2 communicates with the baffle 9 and the vertical baffle 8 through the overflow weir 7, and the lower part of the baffle 9 communicates with the anaerobic chamber II 3 and the anaerobic chamber III 4 in sequence.

[0046] In this solution, the baffle and the vertical baffle are provided, and the treated sewage can overflow into the next anaerobic chamber through the overflow weir in the way of up - and - down pushing flow, with higher efficiency.

[0047] This embodiment also provides a method for collaborative treatment of multi - source sewage on ships, as Figure 2 shown, including:

[0048] S1: Inoculate the domesticated anaerobic oil - removing sludge into the anaerobic chamber I 2, the sulfate - reducing sludge into the anaerobic chamber II 3, and the desulfurizing denitrifying sludge into the anaerobic chamber III 4; the ship's oily sewage enters the anaerobic chamber I 2 through the sampling port I 21, the ship's domestic sewage enters the anaerobic chamber II 3 through the sampling port II 22, and the ship's exhaust gas washing liquid enters the anaerobic chamber III 4 through the sampling port III 23;

[0049] S2: The ship's oily sewage enters the anaerobic chamber I 2 through the sampling port I 21, and is mixed with the anaerobic oil - removing sludge under the action of the mixer 5, and hydrolysis - acidification reaction, oil degradation reaction and sulfate reduction reaction occur. The treated ship's oily sewage overflows into the anaerobic chamber II 3 through the vertical baffle 8 and the baffle 9 between the anaerobic chamber I 2 and the anaerobic chamber II 3, and the generated gas is discharged from the exhaust hole 6 and enters the gas collecting device 13 through the gas collecting pipeline 15 and the gas three - way valve 14;

[0050] S3: The ship's domestic sewage enters the anaerobic chamber II 3 through the sampling port II 22, and is mixed with the treated ship's oily sewage and the sulfate - reducing sludge under the action of the mixer 5, and sulfate reduction reaction occurs. The treated ship's domestic sewage and the secondary - treated ship's oily sewage overflow into the anaerobic chamber III 4 through the vertical baffle 8 and the baffle 9 between the anaerobic chamber II 3 and the anaerobic chamber III 4; the generated gas is discharged from the exhaust hole 6 and enters the gas collecting device 13 through the gas collecting pipeline 15 and the gas three - way valve 14;

[0051] S4: The ship exhaust gas washing liquid enters the anaerobic chamber III 4 through the sampling port III 23, and is mixed with the treated ship oily sewage, ship domestic sewage and desulfurization denitrification sludge under the action of the agitator 5, and the autotrophic / heterotrophic denitrification-sulfate reduction coupling reaction occurs. The generated gas is discharged from the exhaust hole 6 and enters the gas collection device 13 through the gas collection pipeline 15 and the gas three-way valve 14;

[0052] S5: The sewage after S4 treatment flows out from the drain port 25 under the suction filtration of the membrane module 24, passes through the suction pipeline 18 and the liquid three-way valve 19, and enters the collection tank through the water outlet pipe 20 under the action of the suction pump 10. After the membrane module 24 performs suction filtration, the suction pump 10 is started to perform backwashing inside the membrane module 24. When the pressure sensor 17 reaches the set pressure value, the valve of the liquid three-way valve 19 and the backwashing water inlet pipe 29 is opened, and the water flows back to the bottom of the membrane module 24 through the backwashing water inlet pipe 29 under the action of the suction pump 10, and the outside of the membrane module 24 is washed through the swirl water distributor 26; The gas in the gas collection device 13 reaches the bottom of the membrane module 24 through the gas collection pipeline 15 and the gas circulation pipeline 16 under the action of the gas peristaltic pump 11 to wash the outside of the membrane module 24.

[0053] Specifically, first, the domesticated anaerobic oil-removing sludge is inoculated into the anaerobic chamber I, the sulfate-reducing sludge is inoculated into the anaerobic chamber II, and the desulfurization denitrification sludge is inoculated into the anaerobic chamber III; the ship oily sewage enters the anaerobic chamber I through the sampling port I, the ship domestic sewage enters the anaerobic chamber II through the sampling port II, and the ship exhaust gas washing liquid enters the anaerobic chamber III through the water inlet pipe of the sampling port III;

[0054] The ship oily sewage enters the anaerobic chamber I through the sampling port I, and is mixed with the anaerobic oil-removing sludge under the action of the agitator. The oil degradation reaction, hydrolysis acidification reaction and sulfate reduction reaction occur. Under the action of the high-concentration anaerobic oil-removing sludge, the macromolecular organic substances such as oil in the ship oily sewage are degraded into CO2 and water by the combined action of acid-producing bacteria, fermenting bacteria and sulfate-reducing bacteria, and at the same time, SO42- is reduced to S 2- , generating hydrogen sulfide gas and a small amount of methane gas. The gas rises to the exhaust hole and enters the gas collection device; the treated ship oily sewage overflows into the anaerobic chamber II through the vertical plate and baffle of the baffle between the anaerobic chamber I and the anaerobic chamber II; the combined action of the water flow push and the uniform stirring of the stirrer makes the high-concentration sulfate-reducing sludge in the system mix with the ship domestic sewage and the treated ship oily sewage, improving the treatment efficiency;

[0055] The domestic sewage of the ship enters the anaerobic chamber II through the sampling port II, and is mixed with the treated oily sewage of the ship and sulfate-reducing sludge under the action of a mixer, and a sulfate reduction reaction occurs. Under the action of microorganisms mainly composed of sulfate-reducing bacteria, the organic matter in the mixed sewage is removed, and sulfate is reduced to sulfide, part of which exists in the form of hydrogen sulfide gas. The treated domestic sewage of the ship and the oily sewage of the ship after secondary treatment overflow into the anaerobic chamber III through the vertical plate and baffle of the baffle between the anaerobic chamber II and the anaerobic chamber III; the generated gas is discharged from the exhaust hole and enters the gas collection device through the gas pipeline and the gas three-way valve; in this area, the effluent from the anaerobic chamber I brings hydrocarbon substances that have not been completely degraded, and the domestic sewage brings organic pollutants such as proteins and sugars, overcoming the problem of insufficient carbon source in the sulfate reduction reaction and promoting SO4 2- While the reduction is carried out, the oily sewage and domestic sewage of the ship are deeply treated at the same time, using waste to treat waste;

[0056] The ship exhaust gas washing liquid enters the anaerobic chamber III through the sampling port III. Through hydraulic pusher and uniform stirring of the mixer, the ship exhaust gas washing liquid is mixed with high-concentration desulfurization denitrification sludge, and an autotrophic / heterotrophic denitrification-sulfate reduction coupling reaction occurs. The S 2- Generated in the anaerobic chamber II enters the anaerobic chamber III with the water flow, providing an electron donor for autotrophic denitrifying bacteria. The remaining undegraded organic matter in the effluent supplements the substrate for heterotrophic denitrifying bacteria, desulfurizing and denitrifying the ship exhaust gas washing liquid, deeply treating the effluent from the anaerobic chamber II, and at the same time avoiding the problem of secondary pollution caused by adding external carbon sources;

[0057] The treated sewage is filtered by the membrane module and enters the collection tank through the outlet pipe under the action of the suction pump. Gases such as hydrogen sulfide generated in the anaerobic chamber III enter the gas collection device through the exhaust hole and the gas pipeline; while the membrane module is pumping and stopping, it is backwashed. The effluent flows back to the inside of the membrane module through the backwash inlet pipe by the water pump, and the gas reaches the bottom of the membrane module through the gas peristaltic pump through the backwash inlet gas pipeline and is backwashed through the aeration pipe. When the transmembrane pressure difference of the pressure sensor is 30 - 40 kPa, the membrane module is externally rinsed online through the swirl water distributor.

[0058] In this embodiment, the stirring speed of the mixer is 150 rpm, the stirring is intermittent, the operating temperature is 25 - 35 °C, and the hydraulic retention time of each reaction zone is 10 h - 48 h;

[0059] The sludge domestication method is as follows: the hydraulic retention time is 48 h for all, and natural seawater is used; the inlet components of the sulfate-reducing sludge are peptone and sodium bicarbonate; the inlet components of the oil-degrading anaerobic sludge are emulsified diesel and sodium bicarbonate; the denitrification sludge uses sodium sulfide, peptone, sodium nitrate, and sodium bicarbonate; the inoculated activated sludge should be taken from the anaerobic sludge tank or fermentation tank;

[0060] The sludge domestication uses natural seawater to create a high-salt environment, which can promote the rapid formation of a high-salt-tolerant microbial community and facilitate the efficient operation of the desulfurization and denitrification process under high load and high-salt conditions. At the same time, the sludge domestication can be carried out in advance on land, and the successfully domesticated activated sludge is directly inoculated into the reaction device on the ship, greatly shortening the start-up time of the device on the ship, being suitable for the ship operation environment, and not occupying the limited space resources on the ship for sludge domestication.

[0061] The concentration of sludge in each anaerobic zone is as follows:

[0062] The concentration of volatile suspended solids (MLVSS) of the denitrifying sludge inoculated in the anaerobic membrane zone is 2500 - 4500 mg / L; the inoculation concentration of the sludge in the sulfate-reducing anaerobic zone is: 2200 - 3900 mg MLVSS / L; the inoculation concentration of the desulfurizing and denitrifying activated sludge MLVSS is 2500 - 4500 mg / L.

[0063] In a specific embodiment, when the pressure sensor 17 on the suction pipeline 18 is at 30 - 40 Kpa, the suction pump 10 and the gas peristaltic pump 11 are started to perform gas and liquid backwashing on the outside of the membrane module 24.

[0064] In a specific embodiment, the internal backwashing of the membrane module 24 is carried out in an intermittent reflux manner, and the pumping stop time of the membrane module 24 is the same as the time for the suction pump 10 to perform the internal backwashing operation of the membrane module 24.

[0065] The water pumping of the membrane module is 8 min, and the stop time is 1 min; the suction filtration time during backwashing is 8 min, and the time for performing backwashing is 1 min; in this scheme, the suction filtration time of the membrane module is the same as the time for backwashing operation, and the membrane module can be cleaned while the suction filtration of the membrane module ends, improving the effect and efficiency of sewage treatment.

[0066] The overall treatment process of this device is as follows:

[0067] (1) Domestication of activated sludge

[0068] The anaerobic sludge was inoculated from the secondary sedimentation tank of a municipal sewage treatment plant into a continuously stirred reactor. After adding seawater with organic matter and standing for 15 days, the first stirring was carried out while changing the water. After 15 days, simulated wastewater was added to the sewage. The composition of ship oily sewage was: oil concentration, sodium bicarbonate 3.2 g / L; the composition of ship domestic sewage was peptone 1.2 g / L, sodium bicarbonate 8 g / L; the composition of ship exhaust gas washing liquid was: peptone 0.17 g / L, sodium nitrate 0.93 g / L, sodium sulfide 3.33 g / L, sodium bicarbonate 8 g / L. The overall environment was alkaline, and it was dissolved with natural seawater. The HRT was first 48 h and then changed to 24 h. When the oil removal rate of the activated sludge for treating oily sewage was more than 90%, it indicated successful domestication; there was a large amount of sulfate in seawater, and this method only needed to remove the sulfate generated by flue gas washing. Therefore, when the sulfate removal rate of sulfate-reducing activated sludge was more than 70%, it indicated successful domestication; when the sulfide removal rate in desulfurization denitrification sludge was 90% and the nitrate removal rate was more than 90%, it indicated successful domestication;

[0069] (2) Device startup

[0070] The domesticated activated sludge was respectively inoculated into different chambers of the reactor, that is, the desulfurization and oil removal activated sludge was inoculated into anaerobic chamber I, the sulfate-reducing activated sludge SRB was inoculated into anaerobic chamber II, and the desulfurization denitrification activated sludge was inoculated into anaerobic chamber III. Ship oily sewage entered anaerobic chamber I from the sampling port I at the bottom of the shell. Ship domestic sewage was introduced at the bottom of the shell of anaerobic chamber II, and ship exhaust gas washing liquid was introduced at the bottom of anaerobic chamber III. The inlet time and components were the same as those in the sludge domestication stage. The operating temperature was 25 - 35 °C, and stirring was continuously carried out at a stirring speed of 150 rpm. The hydraulic retention time of anaerobic chamber II, anaerobic chamber I, and anaerobic chamber III was 24 h. While the membrane module was being filtered by suction, internal backwashing of the membrane module was carried out, that is, suction filtration for 8 min and backwashing for 1 min.

[0071] (3) Device operation

[0072] The ship sewage in anaerobic chamber I was degraded by microorganisms into small molecule hydrocarbons, CO2, and water; the ship oily sewage entered anaerobic chamber II in a downward plug flow manner above the baffle plate. Ship domestic sewage was introduced at the bottom of the shell of anaerobic chamber II. Under the action of sulfate-reducing bacteria, the organic matter in the mixed sewage was removed, and sulfate was reduced to sulfide; ship exhaust gas washing liquid was introduced at the bottom of anaerobic chamber III and mixed with the effluent of anaerobic chamber II for deep desulfurization, denitrification, and degradation of organic matter. The pumping and stopping time of the effluent from anaerobic chamber III was the same as the backwashing time, and its pumping / stopping time was 8 min / 1 min, that is, suction filtration for 8 min and backwashing for 1 min; at the same time, when the pressure sensor was at 30 - 40 Kpa, the valve was opened, and the outside of the membrane module was backwashed through the backwashing pipe for 5 min.

[0073] Hydrolysis acidification reaction, oil degradation reaction and sulfate reduction reaction occur in anaerobic chamber I. Oils in oily sewage will be adsorbed by microorganisms onto the microbial surface or enter the cells for biochemical metabolism. Complex organic compounds are decomposed into relatively simple small-molecule organic compounds. Microorganisms use the remaining organic compounds as carbon sources and energy sources for their own physiological activities, and end products such as carbon dioxide and water are released during this process.

[0074] Sulfate reduction reaction occurs in anaerobic chamber II. Macromolecular organic compounds such as proteins, carbohydrates, and fats in ship domestic sewage provide electron donors for sulfate-reducing bacteria, and sulfates and organic compounds are efficiently converted into sulfides and small-molecule organic compounds.

[0075] Autotrophic / heterotrophic denitrification-sulfate reduction coupling reaction occurs in anaerobic chamber III. Sulfides and nitrates are converted into elemental sulfur and nitrogen, pollutants in the sewage are removed, and the turbidity of the effluent is ensured after membrane filtration. As Figure 3 shown, the oil removal rate in anaerobic chamber I can reach over 90%, and the organic matter removal rate can reach 94%; as Figure 4 shown, the organic matter removal rate in anaerobic chamber II can reach over 98%, and the SO 24 - removal rate can reach over 74%; as Figure 5 shown, the removal rates of NO3 - and TOC in anaerobic chamber III can both reach over 99%.

[0076] The present invention co-treats various ship sewage, can save space and recycle various harmful gases. The gas internal circulation system in the device can also effectively promote the progress of desulfurization denitrification. The annular membrane module and the agitator are used in combination to increase the membrane flux and the hydraulic cross-flow to scour the membrane module to reduce membrane fouling. The internal and external membrane module backwashing devices can also effectively reduce and prevent membrane fouling. The co-treatment of multi-source ship sewage can promote the synergistic effect of various reactions, thereby improving the overall treatment efficiency and achieving deep purification.

[0077] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A marine multi-stage anaerobic MBR device, characterized in that: include: A reactor shell (1), wherein the reactor shell (1) is provided with an injection port I (21), an injection port II (22) and an injection port III (23); The reactor shell (1) is provided with an anaerobic chamber I (2), an anaerobic chamber II (3) and an anaerobic chamber III (4) which are connected in sequence; the sample inlet I (21) is connected to the anaerobic chamber I (2), the sample inlet II (22) is connected to the anaerobic chamber II (3), and the sample inlet III (23) is connected to the anaerobic chamber III (4); the anaerobic chamber I (2), the anaerobic chamber II (3) and the anaerobic chamber III (4) are provided with A mixer (5), the anaerobic chamber III (4) is also provided with a membrane assembly (24) and a cyclone water distributor (26); baffles (9) and baffle vertical plates (8) are provided on both sides of the anaerobic chamber II (3); a drain port (25) is also provided on the anaerobic chamber III (4); the treated sewage flows out from the drain port (25) through a suction pipeline (18), a suction pump (10) and a backwashing water inlet pipe (29) and flows into the anaerobic chamber III (4); The tops of the anaerobic chamber I (2), anaerobic chamber II (3) and anaerobic chamber III (4) are all provided with exhaust holes (6), and the treated gas is discharged from the exhaust holes (6) and enters the anaerobic chamber III (4) through a gas collecting pipeline (15), a gas circulation pipeline (16), a gas peristaltic pump (11) and a backwashing air inlet pipeline (12).

2. The marine multi-stage anaerobic MBR device according to claim 1, characterized in that: It also includes a gas collecting device (13) and a gas three-way valve (14); one end of the gas collecting device (13) is connected to a gas collecting pipeline (15) via the gas three-way valve (14); the other end of the gas collecting device (13) is connected to one end of a gas circulation pipeline (16); the other end of the gas circulation pipeline (16) is connected to the backwashing air inlet pipeline (12) via a gas peristaltic pump (11).

3. The marine multi-stage anaerobic MBR device according to claim 1, characterized in that: It also includes a water outlet pipe (20) and a pressure sensor (17), wherein the water outlet pipe (20) is externally connected to a water collecting tank; the pressure sensor (17) is arranged on the suction pipeline (18); the treated sewage enters the water collecting tank through a liquid three-way valve (19) and the water outlet pipe (20), and the suction pump (10) draws liquid from the water collecting tank through the water outlet pipe (20) and flows into the anaerobic chamber III (4) through the liquid three-way valve (19) and the backwashing water inlet pipe (29).

4. The marine multi-stage anaerobic MBR device according to claim 1, characterized in that: The stirrer (5) comprises a first stirring paddle (27) and a second stirring paddle (28).

5. The marine multi-stage anaerobic MBR device according to claim 1, characterized in that: The anaerobic chamber I (2) and the anaerobic chamber II (3) are both provided with overflow weirs (7) at their upper parts. The anaerobic chamber I (2) is connected to the baffle plate (9) and the baffle plate vertical plate (8) through the overflow weir (7). The lower part of the baffle plate (9) is connected to the anaerobic chamber II (3) and the anaerobic chamber III (4) in sequence.

6. A method for co-treatment of multi-source sewage from ships based on the ship-based multi-stage anaerobic MBR device according to claim 1, characterized in that: include: S1: The domesticated anaerobic deoiling sludge is inoculated into the anaerobic chamber Ⅰ(2), the sulfate reducing sludge is inoculated into the anaerobic chamber Ⅱ(3), and the desulfurization and denitrification sludge is inoculated into the anaerobic chamber Ⅲ(4); the ship's oily sewage enters the anaerobic chamber Ⅰ(2) through the inlet Ⅰ(21), the ship's domestic sewage enters the anaerobic chamber Ⅱ(3) through the inlet Ⅱ(22), and the ship's exhaust gas scrubbing liquid enters the anaerobic chamber Ⅲ(4) through the inlet Ⅲ(23); S2: The ship's oily sewage enters the anaerobic chamber I (2) through the inlet port I (21), and is mixed with the anaerobic deoiling sludge under the action of the mixer (5), and undergoes hydrolysis and acidification reaction, oil degradation reaction and sulfate reduction reaction. The treated ship's oily sewage overflows into the anaerobic chamber II (3) through the baffle vertical plate (8) and the baffle (9) between the anaerobic chamber I (2) and the anaerobic chamber II (3), and the generated gas is discharged from the exhaust hole (6) and enters the gas collecting device (13) through the gas collecting pipeline (15) and the gas three-way valve (14); S3: The domestic sewage of the ship enters the anaerobic chamber II (3) through the inlet II (22), and is mixed with the treated ship oily sewage and sulfate reduction sludge under the action of the mixer (5), and a sulfate reduction reaction occurs. The treated domestic sewage of the ship and the secondary treated ship oily sewage overflow into the anaerobic chamber III (4) through the baffle vertical plate (8) and the baffle plate (9) between the anaerobic chamber II (3) and the anaerobic chamber III (4); the generated gas is discharged from the exhaust hole (6) and enters the gas collecting device (13) through the gas collecting pipeline (15) and the gas three-way valve (14); S4: The ship exhaust gas washing liquid enters the anaerobic chamber III (4) through the inlet port III (23), and is mixed with the treated ship oily sewage, ship domestic sewage and desulfurization and denitrification sludge under the action of the mixer (5), and an autotrophic / heterotrophic denitrification-sulfate reduction coupling reaction occurs. The generated gas is discharged from the exhaust hole (6) and enters the gas collection device (13) through the gas collection pipeline (15) and the gas three-way valve (14); S5: The wastewater treated in S4 flows out from the drain port (25) through the suction pipe (18) and the liquid three-way valve (19), and enters the water collection tank through the outlet pipe (20) under the action of the suction pump (10). After the membrane assembly (24) is filtered, the suction pump (10) is started to backwash the inside of the membrane assembly (24). When the pressure sensor (17) reaches the set pressure value, the liquid three-way valve (19) is opened to The valve of the backwash water inlet pipe (29) allows the outlet water to flow back to the bottom of the membrane assembly (24) through the backwash water inlet pipe (29) under the action of the suction pump (10), and flush the outside of the membrane assembly (24) through the cyclone water distributor (26); the gas in the gas collecting device (13) reaches the bottom of the membrane assembly (24) through the gas collecting pipeline (15) and the gas circulation pipeline (16) through the action of the gas peristaltic pump (11), and flushes the outside of the membrane assembly (24).

7. The method for coordinating treatment of multi-source sewage from ships according to claim 6, characterized in that: When the pressure sensor (17) on the suction pipeline (18) is at 30-40 KPa, the suction pump (10) and the gas peristaltic pump (11) are started to perform gas and liquid backwashing on the outside of the membrane assembly (24).

8. The method for coordinating treatment of multi-source sewage from ships according to claim 6, characterized in that: An intermittent reflux method is used to perform backwashing inside the membrane assembly (24), and the time when the membrane assembly (24) is pumped and stopped is consistent with the time when the suction pump (10) performs backwashing operation inside the membrane assembly (24).

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