An offshore oil spill treatment device and a method for treating offshore oil spills

Abstract

The present invention discloses an offshore oil spill treatment device and a method for treating offshore oil spills, belonging to the technical field of offshore oil spill treatment. The inlet baffle of the treatment pool of the treatment device of the present invention adopts an arc surface design, and the front ends of the two floating bodies on both sides adopt a conical design, which are both beneficial to reducing the resistance when the treatment device travels on the sea surface; the inlet of the treatment pool is designed in a "T" shape, which not only ensures the smooth entry of the oil-containing seawater on the surface layer, but also is conducive to the uniform up-and-down flow of seawater in the treatment pool. The horizontal inlet is long, which can ensure that the inlet water is mainly the oil-containing seawater on the surface layer, and the vertical inlet is shorter, which can allow the lower layer of water to flow through and reduce the resistance; the inner part of the treatment pool is divided into several bins, and the bins are filled with high-density immobilized microbial agents, which can perform hierarchical treatment on the oil-containing seawater, thereby improving the treatment efficiency; the two thrusters at the rear end of the floating body can be controlled separately, and by adjusting the speeds of the two thrusters, the forward movement and turning of the experimental device can be achieved, making the operation more flexible.

Description

Technical Field

[0001] The present invention belongs to the technical field of offshore oil spill treatment, and in particular relates to an immobilized microbial agent, an offshore oil spill treatment device carrying the agent, and a method for treating offshore oil spills. Background Art

[0002] As the lifeblood of modern industry, oil plays an increasingly crucial role in human production and daily life. With increasing demand for oil, oil spills and leaks during extraction, transportation, processing, and use are becoming increasingly frequent, posing a significant threat to the marine environment. Water pollution is closely linked to human activities, particularly the contamination of slow-flowing offshore waters, which poses a serious threat to human survival. Compared to physical and chemical remediation, microbial remediation offers an ideal approach for remediating marine oil pollution, offering lower costs, fewer residual issues, and no secondary pollution.

[0003] Although there have been many related inventions in the field of bioremediation of marine oil pollution at home and abroad, they are still not widely used in actual pollution control incidents. The main reasons are: (1) The marine environment is complex, and the effects of waves and tides make it difficult for microorganisms to gather, resulting in poor remediation effects; (2) Most microbial preparations are added in a demarcated area and are not suitable for situations where the pollution area is large; (3) Microbial preparations are mostly added once and are not easy to recover. The metabolites after microbial remediation will have unknown effects on the marine environment and changes in the bacterial community. Due to the low mobility and weak self-purification ability of slow-flowing water bodies in coastal areas, oil pollution is prone to accumulation, and the remediation of micro-polluted offshore waters has problems such as difficulty in collecting and treating floating oil. Therefore, how to solve technical problems such as low microbial density, small remediation area, and inconvenient recovery is of great significance to the remediation of actual marine pollution by microorganisms. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide an immobilized microbial agent, a marine oil spill treatment device carrying the agent, and a marine oil spill treatment method. The prepared immobilized microbial agent is placed in the marine oil spill treatment device and released into an oil-contaminated sea area to adsorb and immobilize the floating oil on the surface, followed by biodegradation. This achieves a combination of microbial and physical remediation, effectively resolving issues such as low microbial density, small remediation area, and inconvenient recovery during microbial remediation of oil-contaminated sea areas, thereby significantly improving the efficiency of microbial remediation of oil-contaminated sea areas.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An immobilized microbial agent is an immobilized microsphere prepared by adding a cross-linking agent solution to a mixed solution of sodium alginate - carbonized dry powder - petroleum-degrading bacteria; the petroleum-degrading bacteria include Halomonas bacteria that degrade petroleum and Bacillus aneurinolyticus bacteria that produce biosurfactants.

[0007] On the basis of the above scheme, the ratio of Halomonas bacteria to Bacillus aneurinolyticus bacteria in the petroleum-degrading bacteria is 1:1 (v / v); among them, the effective viable count of Halomonas bacteria is 1×10 8 -1×10 9 cfu / mL, and the effective viable count of Bacillus aneurinolyticus bacteria is 2×10 7 -2×10 8 cfu / mL.

[0008] Both the Halomonas bacteria and the Bacillus aneurinolyticus bacteria are strains that can be purchased on the market or are disclosed in existing literature.

[0009] On the basis of the above scheme, the mixed solution of sodium alginate - carbonized dry powder - petroleum-degrading bacteria is prepared by the following method:

[0010] Mix the carbonized dry powder with a sterilized sodium alginate solution with a mass fraction of 3%-5%, and the ratio is 1% (m / v), then add the petroleum-degrading bacteria suspension, and the ratio of the petroleum-degrading bacteria suspension to the sodium alginate solution is 1:3 - 1:5 (v / v), stir evenly to obtain the mixed solution of sodium alginate - carbonized dry powder - petroleum-degrading bacteria.

[0011] On the basis of the above scheme, the cross-linking agent solution is a CaCl2 solution with a mass fraction of 3%-5%.

[0012] On the basis of the above scheme, the carbonized dry powder is a dry powder prepared from agricultural plant fibrous waste by carbonization.

[0013] On the basis of the above scheme, the preparation method of the carbonized dry powder is as follows:

[0014] Wash the agricultural plant fibrous waste with clean water and ethanol solution, dry it at 105°C for 2h, then crush it, screen out particles of 2 - 4mm, heat it under nitrogen at 220 - 280°C for 2h to obtain carbonized particles; further grind and crush the carbonized particles to a particle size <1mm, wash the obtained dry powder material with clean water and ethanol 2 - 3 times to wash off the surface impurities, and dry it at 105°C for 2h to obtain the carbonized dry powder.

[0015] On the basis of the above scheme, the preparation method of the immobilized microbial agent is as follows:

[0016] Drop the sodium alginate-carbonized dry powder-petroleum-degrading bacteria mixture into the cross-linking agent CaCl2 solution to obtain an immobilized microbial agent. Transfer the immobilized microbial agent to a sealed bottle, continue to soak it in the cross-linking agent for a period of time, wash it 2-3 times with sterilized physiological saline, and finally soak it in distilled water and store it at 4°C for later use. It can be directly fished out and used when needed. CaCl2 can quickly undergo ion exchange with the sodium alginate solution to form a gel. The principle of the sodium alginate to produce a gel is to react with Ca 2 + to react and cannot react with other substances.

[0017] An offshore oil spill treatment device includes: a treatment tank (1) and a bin partition net (2). A cavity is formed inside the treatment tank (1). An inlet (11) is formed in front of the treatment tank (1), and an outlet (12) is formed behind the hull. The bin partition net (2) is detachably connected to the treatment tank (1), and the immobilized microbial agent prepared by the above method is arranged between the bin partition nets (2); the bin partition net (2) is used to prevent the immobilized microbial agent from passing through the bin partition net.

[0018] On the basis of the above solution, air bags (3) are fixedly installed on both sides of the treatment tank (1), and a propulsion device (4) is installed on the air bags (3).

[0019] On the basis of the above solution, the treatment tank (1) includes a treatment tank bottom plate (13), side baffles (14), an inlet baffle (15), an overflow weir baffle (16) and a treatment tank top plate (17). Both sides of the treatment tank bottom plate (13) are fixedly connected to the side baffles (14), the front of the treatment tank bottom plate (13) is fixedly connected to the inlet baffle (15), the rear of the treatment tank bottom plate (13) is fixedly connected to the overflow weir baffle (16), and the upper part of the side baffles (14) is fixedly connected to the treatment tank top plate (17).

[0020] On the basis of the above solution, the side baffle (14) is formed with a card slot, and the bin partition net (2) passes through the treatment tank top plate (17) and is inserted into the card slot.

[0021] On the basis of the above solution, the treatment tank top plate (17) is formed with a feed inlet (171).

[0022] On the basis of the above solution, the feed inlet (171) is detachably connected to a feed inlet plug.

[0023] On the basis of the above solution, the shape of the inlet (11) is T-shaped.

[0024] On the basis of the above solution, sawteeth are formed above the overflow weir baffle (16).

[0025] A method for treating marine oil spills, characterized by the following steps:

[0026] (1) Loading stage

[0027] First, place the bunker partition net of the marine oil spill treatment device into the corresponding card slots in the treatment pool; then load the immobilized microbial inoculant into the bunker from the feed inlet, with the loading amount being approximately two-thirds of the bunker volume; finally, plug the feed inlet to complete the loading.

[0028] (2) Commissioning stage

[0029] First, fix two elastic ropes diagonally on the four hanging rings on the top plate of the treatment pool of the marine oil spill treatment device, and fix the main hanging ring at the intersection of the rope diagonals; then hook the main hanging ring with the cantilever crane, lift the device to keep it balanced, and slowly lower it into the sea oil spill point; after the device stabilizes, detach the main hanging ring from the hook to complete the operation of putting it into the water.

[0030] (3) Adsorption and biodegradation stage

[0031] Control the marine oil spill treatment device to move forward at a constant speed. The oil-containing seawater flows into the treatment pool from the inlet and outlet, enters the bunker after passing through the bunker partition net, and the adsorption stage begins; the oil-containing seawater can come into full contact with the immobilized microbial inoculant in the bunker as it flows, and the oil is adsorbed by the immobilized microbial inoculant and then flows into the subsequent bunker for further adsorption; the seawater after adsorption treatment flows through the last bunker partition net and then is discharged from the overflow weir outlet; the adsorbed oil is degraded by the immobilized microbial inoculant; it is advisable to ensure that the hydraulic retention time is 0.5 - 5 hours.

[0032] (4) Recovery stage

[0033] After operating for 1 - 4 hours, when it is observed that the immobilized microbial inoculant is significantly broken or the degradation efficiency significantly decreases, start the recovery procedure. Stop the marine oil spill treatment device under the cantilever crane, hook the main hanging ring, and lift the device; after the seawater in the treatment pool drains out, lift it ashore; remove the main hanging ring and the elastic ropes, draw out the bunker partition net, and recover the immobilized microbial inoculant from the water inlet.

[0034] (5) Onshore treatment stage

[0035] The recovered immobilized microbial agent is processed onshore. This process involves two steps: if the fragmentation rate is high, the fragmented immobilized microbial agent is filtered out and discarded; if the degradation efficiency decreases significantly, in addition to filtering out a small amount of fragmented immobilized microbial agent and discarding it, the intact immobilized microbial agent is placed in an onshore treatment tank, where an appropriate amount of nitrate, phosphate, and other nutrient solutions (with an N:P ratio of 5:1 to 10:1) are added. The temperature is controlled at 30°C, the agent is stirred at 160 rpm / min, and aerated appropriately for activation. The activation cycle is generally 1-2 days. Once the degradation rate has recovered to 70%, the immobilized microbial agent is filtered out and can be reused after cleaning. If the immobilized microbial agent still cannot recover to 70% after activation, it is discarded.

[0036] Advantages of the technical solution of the present invention

[0037] (1) The immobilized carrier used is a resource utilization of agricultural plant fiber waste

[0038] The immobilized microbial agent in this invention uses corn straw, a fibrous agricultural waste, as an immobilization carrier. The nitrogen and phosphorus elements contained in corn straw support the growth and reproduction of petroleum-degrading bacteria. Even after modification, corn straw still provides nutrients for the growth of petroleum-degrading bacteria. Using corn straw as an immobilized carrier for petroleum-degrading bacteria allows for its resourceful utilization.

[0039] (2) Combination of microbial remediation technology and physical remediation technology

[0040] Common surface oil removal systems (such as skimmers) typically use physical methods to recover floating oil, followed by secondary treatment. This method is generally suitable for large amounts of floating oil on the surface; smaller amounts are difficult to recover and treat. This device combines microbial remediation with physical remediation technologies. Specifically for sites where floating or emulsified petroleum hydrocarbons are physically collected after an oil spill, it can simultaneously collect, treat, and discharge the oily seawater. This device offers flexibility, ease of operation, high treatment efficiency, and zero secondary pollution.

[0041] (3) The structure of the device itself is advanced

[0042] From the perspective of improving the treatment efficiency of oily seawater, the structural design of this treatment device has the following advantages: the baffle at the inlet of the treatment tank adopts an arc-shaped design, and the front ends of the two floating bodies on both sides adopt a conical design, both of which are conducive to reducing the resistance of the treatment device when moving on the sea surface; the inlet of the treatment tank is designed in a "T" shape, which not only ensures the smooth entry of the surface oily seawater but also facilitates the uniform up-and-down flow of seawater in the treatment tank. The horizontal inlet is long, which can ensure that the inlet water is mainly surface oily seawater, and the vertical inlet is shorter, which can allow the lower-layer water to flow through and reduce the resistance; the inside of the treatment tank is divided into several bins filled with high-density immobilized microbial agents, which can perform hierarchical treatment on the oily seawater, thereby improving the treatment efficiency; the two thrusters at the rear end of the floating body can be controlled separately, and adjusting the speeds of the two thrusters can achieve the forward movement and turning of the experimental device, making the operation more flexible.

[0043] (4) High treatment method efficiency

[0044] The device and treatment method of the present invention can remove a certain amount of residual floating oil, emulsified oil and other petroleum hydrocarbons after physical collection, and can achieve the removal of more than 70% of the petroleum hydrocarbons in the above-mentioned petroleum hydrocarbon polluted areas. The device and treatment method of the present invention are mainly applicable to the oil spill pollution of offshore oil production platforms, and are also applicable to the restoration of petroleum pollution in slow-flowing near-shore waters such as coasts, ports, and docks. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 Treatment effect diagram of the treatment method for offshore oil spills of the present invention;

[0046] Figure 2 Removal effects under different pollution conditions (1# treatment area is 50m 2 , average forward speed is 2m / min, oil concentration is 5%, degradation rate is 78%; 2# treatment area is 50m 2 , average forward speed is 3m / min, oil concentration is 5%, degradation rate is 67%; 3# treatment area is 50m 2 , average forward speed is 2m / min, oil concentration is 10%, degradation rate is 71%;)

[0047] Figure 3 Structural schematic diagram of the offshore oil spill treatment device of the present invention;

[0048] Figure 4 Internal structure diagram of the treatment tank;

[0049] Figure 5 Bottom view of the device;

[0050] Figure 6 Rear view of the device. DETAILED DESCRIPTION OF THE INVENTION

[0051] The terms used in the present invention generally have the meanings commonly understood by those of ordinary skill in the art, unless otherwise specified.

[0052] The present invention will be further described in detail below with reference to specific embodiments and data. The following embodiments are only for illustrative purposes of the present invention and do not limit the scope of the present invention in any way.

[0053] Example 1

[0054] Preparation of immobilized microbial inoculum

[0055] A. Dry powder carbonization

[0056] Select agricultural plant fibrous waste (such as straw), wash it with clear water and ethanol solution, dry it at 105 °C for 2 h, then crush it, screen out particles of 2 - 4 mm, and heat it under nitrogen at 220 - 280 °C for 2 h to obtain carbonized particles.

[0057] B. Preparation and storage of inoculum

[0058] Further grind and crush the carbonized particles to a particle size < 1 mm. Wash the obtained carbonized dry powder material with clear water and ethanol several times, 2 - 3 times with clear water and then 2 - 3 times with absolute ethanol, to wash away the surface impurities, and dry it at 105 °C for 2 h. Mix the dried carbonized dry powder with a sterilized sodium alginate solution with a mass fraction of 3% - 5%. The ratio of the carbonized dry powder to the sodium alginate solution is 1% (m / v). Then add a petroleum-degrading bacterial suspension (composed of bacteria of the genus Halomonas that degrade petroleum and bacteria of the genus Bacillus aneurinolyticus that produce biosurfactant in a ratio of 1:1 (v / v). The effective viable count of the bacteria of the genus Halomonas is 1×10 8 ~1×10 9 cfu / mL, and the effective viable count of the bacteria of the genus Bacillus aneurinolyticus is 2×10 7 -2×10 8 cfu / mL). The ratio of the petroleum-degrading bacterial liquid to the sodium alginate solution is 1:3 - 1:5 (v / v). Stir evenly to obtain a sodium alginate-carbonized dry powder-petroleum-degrading bacteria mixture. Drop the above sodium alginate-carbonized dry powder-petroleum-degrading bacteria mixture drop by drop into a CaCl2 solution with a mass fraction of 3% - 5% to obtain an immobilized microbial inoculum. Transfer the immobilized microbial inoculum to a sealed bottle, continue to soak it in a cross-linking agent for a period of time, wash it 2 - 3 times with sterilized normal saline, and finally soak it in distilled water and store it at 4 °C for later use. Just take it out directly when in use.

[0059] Petroleum degradation experiments were conducted using free bacteria (free bacteria group), microbial agents prepared from uncarbonized agricultural plant fibrous waste (uncarbonized microsphere group), and microbial agents prepared from carbonized agricultural plant fibrous waste (carbonized microsphere group), respectively. Among them, the experiment of the free bacteria group was carried out using Halomonas bacteria and Thiaminolyticum bacteria in a ratio of 1:1 (v / v), adding diesel oil and seawater, and the ratio of the bacterial solution, diesel oil, and seawater was 1:5:100 (v / v); the experiment of the uncarbonized immobilized microbial agent group was carried out by mixing agricultural plant fibrous waste and a sterilized sodium alginate solution with a mass fraction of 4% in a ratio of 1% (m / v), and then adding a petroleum-degrading bacteria suspension of Halomonas bacteria and Thiaminolyticum bacteria in a ratio of 1:1 (v / v). The ratio of the petroleum-degrading bacteria suspension (the amount of added bacterial solution was roughly the same as that of the free bacterial solution) to the sodium alginate solution was 1:5 (v / v). After stirring evenly, a sodium alginate-dry powder-petroleum-degrading bacteria mixture was obtained, which was dropped into the CaCl2 solution drop by drop to form an uncarbonized immobilized microbial agent, and diesel oil, seawater, and the uncarbonized immobilized microbial agent were added; the experiment of the carbonized microsphere group was carried out by mixing carbonized agricultural plant fibrous waste and a sterilized sodium alginate solution with a mass fraction of 4% in a ratio of 1% (m / v), and then adding a petroleum-degrading bacteria suspension of Halomonas bacteria and Thiaminolyticum bacteria in a ratio of 1:1 (v / v). The ratio of the petroleum-degrading bacteria suspension (the amount of added bacterial solution was roughly the same as that of the free bacterial solution) to the sodium alginate solution was 1:5 (v / v). After stirring evenly, a sodium alginate-dry powder-petroleum-degrading bacteria mixture was obtained, which was dropped into the CaCl2 solution drop by drop to form a carbonized immobilized microbial agent, and diesel oil, seawater, and the carbonized immobilized microbial agent were added. At the same time, the degradation rate was measured, and the results are as Figure 1 shown. The degradation rate of free bacteria was 47%, that of the uncarbonized immobilized microbial agent was 58%, and that of the carbonized immobilized microbial agent was 72%.

[0060] Example 2

[0061] An offshore oil spill treatment device is as Figures 3 - 6 shown, generally in the structure of a catamaran-like ship, 12 m long, 8 m wide, and 1 m high. The main structure consists of a treatment tank and floating bodies on both sides.

[0062] (1) Treatment tank

[0063] The treatment tank is 12 m long, 4 m wide, and 1 m high, and mainly consists of an inlet baffle, a treatment tank bottom plate, an overflow weir baffle, side baffles, a bin partition net, and a treatment tank top plate.

[0064] The overall structure of the water inlet baffle is arc-shaped, which can reduce the resistance of the treatment tank when moving on the sea surface; the upper end of the water inlet baffle is 0.2 m away from the top plate of the treatment tank, forming a horizontal water inlet; there is a vertical water inlet at the center position of the water inlet baffle, with a width of 0.4 m and a length of 0.7 m; the horizontal water inlet is connected to the vertical water inlet to form a "T"-shaped water inlet, which can not only ensure that the main inlet water is the surface oil-containing seawater, but also ensure the flow of seawater in the middle and bottom of the treatment tank.

[0065] The bottom plate of the treatment tank is rectangular, with a length of 10 m and a width of 4 m. The front end is connected to the water inlet baffle, the rear end is connected to the overflow weir baffle, and the two sides are connected to the side baffles; there are three buckles evenly distributed before and after at the center of the outside of the bottom plate of the treatment tank, which are used to fix the floating bodies on both sides of the treatment tank.

[0066] The overflow weir baffle is rectangular, with a length of 4 m and a width of 0.8 m. The upper part of the side of the overflow weir baffle is serrated, 0.2 m away from the top plate of the treatment tank, forming an outlet; the serrated overflow weir can make the water outlet uniform and have good stability.

[0067] There are 2 side baffles in total, symmetrically distributed on the left and right, with a length of 12 m and a width of 1 m. The bottom edge of the front end is arc-shaped and is connected to the water inlet baffle, and the other sides are respectively connected to the bottom plate of the treatment tank, the overflow weir baffle, and the top plate of the treatment tank; there are 5 groups of card slots on the inner sides of the two side baffles, symmetrically distributed in pairs, which are used to place the bin partition nets.

[0068] The bin partition net is composed of a rectangular net frame and a partition net. The length of the net frame is slightly less than 4 m, which is convenient for inserting it into the card slot of the side baffle. The width is slightly greater than 1 m, which is convenient for taking it out of the card slot. The thickness of the net frame is about 30 mm; the partition net is tightened around the net frame, and the diameter of the mesh holes is less than 5 mm to prevent the immobilized microbial inoculant from flowing out; there are 5 bin partition nets in total, perpendicular to the bottom plate of the treatment tank, evenly distributed, and dividing the inner part of the treatment tank into four equal-sized bins.

[0069] The top plate of the treatment tank is rectangular, with a length of 12 m and a width of 4 m. The two sides are connected to the side baffles; there are gaps at the positions corresponding to the bin partition nets on the top plate of the treatment tank, with a width of about 40 mm, which is convenient for inserting and taking out the bin partition nets; there are feeding holes at the center positions of each bin on the top plate of the treatment tank, with a diameter of 50 mm; at the positions corresponding to the buckles on the bottom plate of the treatment tank on the outside of the top plate of the treatment tank, 3 identical buckles are set, which are used to fix the floating bodies on both sides of the treatment tank; there are 4 lifting rings symmetrically distributed near the four corners of the top plate of the treatment tank, which are used to fix the elastic ropes and facilitate the lifting of this device.

[0070] (2) Floating body

[0071] The floating bodies are symmetrically distributed on the left and right sides of the treatment tank, with 2 in total, with a length of 12.5 m and a diameter of 1 m. They are mainly divided into two parts: an airbag and a thruster.

[0072] The airbag as a whole is wedge-shaped, 12 m long and 1 m in diameter, and is divided into two parts: the front end and the rear end; the front end is conical, 2 m long, and the tip is flush with the water inlet. The conical shape can reduce the resistance of the device when moving on the sea surface; the rear end is cylindrical, 10 m long. At the position corresponding to the buckle on the top plate of the treatment tank, 3 identical buckles are provided. At the position corresponding to the buckle on the bottom plate of the treatment tank, 3 identical buckles are provided; the buckles on the two airbags are respectively connected to the buckles on the top plate and the bottom plate of the treatment tank through 6 steel pipes and fixed.

[0073] The thruster is 0.5 m long and 1 m in diameter as a whole, and is mainly divided into four parts: a propeller, a protective ring, a coupling motor and a storage battery; the propeller provides power for the device to move forward, and the rotation speed can be adjusted; the protective ring can prevent sea surface sundries, etc. from winding around the propeller and play a protective role for the propeller; the coupling motor is fixed at the rear end of the airbag, connects the propeller, and is the main power source; the storage battery is arranged inside the airbag to prevent contact with sea water and supplies power to the coupling motor. A charging hole is provided at the rear end of the airbag.

[0074] Example 3

[0075] A method for treating offshore oil spills

[0076] (1) Loading stage

[0077] First, put the bin partition net into the corresponding card slot in the treatment tank; then the immobilized microbial inoculant is loaded into the bin from the feed inlet, and the loading amount is about two-thirds of the bin volume; finally, plug the feed inlet, and the loading is completed. It can be divided into several sections through the fine pore sieve according to the dosing amount. It can play the effect of hierarchical treatment during the operation process.

[0078] (2) Commissioning stage

[0079] First, fix two elastic ropes diagonally on the four hanging rings on the top plate of the treatment tank respectively, and fix the main hanging ring at the intersection of the rope diagonals; then hook the main hanging ring with a cantilever crane, lift the device to keep it balanced, and slowly put it into the offshore oil spill point; after the device is stable, make the main hanging ring disengage from the hook, and the commissioning is completed.

[0080] (3) Adsorption and biodegradation stage

[0081] Control the offshore oil spill treatment device to move forward at a constant speed. The oily seawater flows into the treatment tank from the inlet and outlet, enters the bin after passing through the bin partition net, and the adsorption stage begins; the oily seawater can come into full contact with the immobilized microbial inoculant in the bin as it flows, and the oil is adsorbed by the immobilized microbial inoculant and then flows into the subsequent bin for further adsorption; the seawater after adsorption treatment flows through the last bin partition net and then is discharged from the overflow weir outlet; the adsorbed oil is degraded by the immobilized microbial inoculant; it is advisable to ensure that the hydraulic retention time is 0.5 - 5 hours.

[0082] (4) Recovery stage

[0083] After running for 1 - 4 hours, when it is observed that the immobilized microbial agent is significantly broken or the degradation efficiency significantly decreases, start the recovery procedure. Stop the offshore oil spill treatment device under the cantilever crane, hook the main lifting ring, and lift the device; after the seawater in the treatment tank has drained out, lift it ashore; remove the main lifting ring and the elastic rope, pull out the bin partition net, and recover the immobilized microbial agent from the water inlet.

[0084] (5) Onshore treatment stage

[0085] Conduct onshore treatment on the recovered immobilized microbial agent. This includes two aspects. When the breakage rate is relatively high, filter out the broken immobilized microbial agent and discard it; when the degradation efficiency significantly decreases, in addition to filtering out a small amount of broken immobilized microbial agent and discarding it, place the intact immobilized microbial agent in an onshore treatment tank, add an appropriate amount of nutrient salt solutions such as nitrates and phosphates (with the N:P ratio in the range of 5:1 - 10:1), control the temperature at 30°C, stir at a speed of 160 rpm / min, and aerate appropriately for activation treatment. The activation period is generally 1 - 2 days. When the degradation rate is measured to have recovered to 70%, filter out the immobilized microbial agent, clean it, and it can be reused; when the immobilized microbial agent still cannot recover to 70% after activation, discard the immobilized microbial agent.

[0086] As described above, it is only the preferred embodiment of the present invention, and it is not a limitation of the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An offshore oil spill treatment device, characterized in that, Comprising: A treatment tank (1) and a bin partition net (2). A cavity is formed inside the treatment tank (1). An inlet (11) is formed in front of the treatment tank (1), and an outlet (12) is formed at the rear of the hull. The bin partition net (2) is detachably connected to the treatment tank (1), and an immobilized microbial agent is arranged between the bin partition nets (2); the bin partition net (2) is used to restrict the immobilized microbial agent from passing through the bin partition net. The immobilized microbial agent is an immobilized microsphere prepared by adding a crosslinking agent solution to a mixed solution of sodium alginate - carbonized dry powder - petroleum - degrading bacteria; the petroleum - degrading bacteria include Halomonas bacteria that degrade petroleum and Bacillus aneurinolyticus bacteria that produce biosurfactants. The ratio of Halomonas bacteria to Bacillus aneurinolyticus bacteria in the petroleum-degrading bacteria is 1:1 (v / v); the effective viable count of Halomonas bacteria is 1×10 8 ~1×10 9 cfu / mL, and the effective viable count of Bacillus aneurinolyticus bacteria is 2×10 7 ~2×10 8 cfu / mL; The mixed solution of sodium alginate - carbonized dry powder - petroleum - degrading bacteria is prepared by the following method: Mix the carbonized dry powder with a sterilized sodium alginate solution with a mass fraction of 3% - 5%. The ratio of the carbonized dry powder to the sodium alginate solution is 1% (m / v); then add a petroleum - degrading bacteria suspension, and the ratio of the petroleum - degrading bacteria suspension to the sodium alginate solution is 1:3 - 1:5 (v / v); stir evenly to obtain the mixed solution of sodium alginate - carbonized dry powder - petroleum - degrading bacteria. Agricultural plant fibrous waste is washed with clean water and an ethanol solution, dried at 105°C for 2 h, then crushed, and particles of 2 - 4 mm are screened out, and heated with nitrogen at 220 - 280°C for 2 h to obtain carbonized particles; the carbonized particles are further ground and crushed to a particle size < 1 mm, and the obtained dry powder material is washed with clean water and ethanol to wash away the surface impurities, and dried at 105°C for 2 h to obtain carbonized dry powder. Drop the mixed solution of sodium alginate - carbonized dry powder - petroleum - degrading bacteria into the crosslinking agent solution to obtain the immobilized microbial agent; transfer the prepared immobilized microbial agent to a sealed bottle, continue to soak in the crosslinking agent for a period of time, wash 2 - 3 times with sterilized physiological saline, and finally soak in distilled water and refrigerate at 4°C.

2. The offshore oil spill treatment device according to claim 1, characterized in that, Air bags (3) are fixedly installed on both sides of the treatment tank (1), and a propulsion device (4) is installed on the air bags (3).

3. The offshore oil spill treatment device according to claim 1 or 2, characterized in that The treatment tank (1) includes a treatment tank bottom plate (13), side baffles (14), an inlet baffle (15), an overflow weir baffle (16), and a treatment tank top plate (17). Both sides of the treatment tank bottom plate (13) are fixedly connected to the side baffles (14), the front of the treatment tank bottom plate (13) is fixedly connected to the inlet baffle (15), the rear of the treatment tank bottom plate (13) is fixedly connected to the overflow weir baffle (16), and the upper part of the side baffles (14) is fixedly connected to the treatment tank top plate (17); a card slot is formed in the side baffle (14), and the bin partition net (2) passes through the treatment tank top plate (17) and is inserted into the card slot.

4. The offshore oil spill treatment device according to claim 1, wherein, The crosslinking agent solution is a CaCl2 solution with a mass fraction of 3% - 5%.

5. A method for treating offshore oil spills using the device according to any one of claims 1-4, characterized in that, The steps are as follows: (1) Loading stage First, install the bin partition net of the offshore oil spill treatment device into the treatment tank; then load the immobilized microbial agent into the bin. (2) Commissioning stage Put the offshore oil spill treatment device loaded with the immobilized microbial agent into the sea oil spill point. (3) Adsorption and biodegradation stage Operate the offshore oil spill treatment device to make the oil-containing seawater flow into the treatment tank from the inlet and outlet, and enter the bin after passing through the bin partition net. The adsorption stage begins; the oil-containing seawater can come into full contact with the immobilized microbial agent in the bin as it flows, and the oil is adsorbed by the immobilized microbial agent, and then flows into the subsequent bin for further adsorption; the seawater after adsorption treatment flows through the last bin partition net and then is discharged from the overflow weir outlet; the adsorbed oil is degraded by the immobilized microbial agent. (4) Recovery stage After the adsorption stage is completed, lift the offshore oil spill treatment device; after the seawater in the treatment tank has drained, lift it ashore; recover the immobilized microbial agent in the recovery bin. (5) Onshore treatment stage The recovered immobilized microbial agent is filtered to remove the broken immobilized microbial agent, and then undergoes activation treatment. After activation, the degradation rate of the immobilized microbial agent is measured to recover to 70%, and it is reused; if the degradation rate still cannot recover to 70% after activation, it will be discarded.

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