CN201940168U - Marine desulfurization system using magnesium-based seawater method - Google Patents
Marine desulfurization system using magnesium-based seawater method Download PDFInfo
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- CN201940168U CN201940168U CN2011200405654U CN201120040565U CN201940168U CN 201940168 U CN201940168 U CN 201940168U CN 2011200405654 U CN2011200405654 U CN 2011200405654U CN 201120040565 U CN201120040565 U CN 201120040565U CN 201940168 U CN201940168 U CN 201940168U
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Abstract
The utility model relates to a marine desulfurization system using a magnesium-based seawater method, which mainly comprises a desulfurization tower, a seawater cooling and spraying unit, a pulp tank, a multi-stage spraying device and seawater. Fume of a ship boiler is cooled through seawater spraying driven by a fan, so that the temperature of the fume is reduced to be below 100 DEG C. Due to reaction of Mg(OH)2 pulp spray mist of the multi-stage spraying device and SO2 in the fume of the boiler, the concentration of the SO2 in the fume of the boiler can be reduced and meets standards, a reaction product MgSO3 falls into the pulp tank along spray mist liquid, and MgSO4 can be generated through oxidation and is discharged during drainage. By adopting the system, the application of the desulfurization technology using the magnesium-based seawater method in high-efficiency desulfurization of the ship fume can be realized, the marine desulfurization system can reliably operate in a long term and meets the standards, and solid technical preparation is made for China's implementation of novel standards on the sulfur content in ship fuels according to IMO (International Maritime Organization) requirements.
Description
Technical field
The utility model relates to the flue gas desulfurization technique field, refers more particularly to the system of magnesium method and the desulfurization of seawater method.
Background technology
The sulfur content standard that the bunker fuel oil executed is very strict allows the emission-reduction technology of ship use through approval simultaneously, and condition is SO
2Discharging is equal to or less than the Low Sulfur Fuel Oil of burning 0.10%.Adopt the low fuel oil of sulfur-bearing will significantly improve vessel operating cost, so flue gas desulfurization becomes the most practicable selection of reply new standard.
With respect to dry method and semidry method, wet desulphurization is used widely with its mature technique.The most successful desulfur technology that reaches commercial Application is a chemical method at present, comprises calcium method, magnesium method and the desulfurization of seawater method.The influence of factors such as handle in geographical position, desulfuration byproduct because the seawater method is subjected to, desulfurizing agent source and price, usually be applied in that regionality is strong, exhaust gas volumn is less relatively or the better simply desulfurization project of technological requirement in; Lime (stone)-gypsum law technology maturation, low price, desulfuration efficiency height, so use morely, but its operating cost height, secondary pollution seriously, easily cause pipeline scale to stop up; The desulfurization of magnesium method has that system is simple, security of operation, reliability height, operating cost is low, desulfuration efficiency is high, applied widely, less scaling, non-secondary pollution, by-product utilization are worth more high relatively advantage, and the trend that progressively replaces the desulfurization of calcium method was arranged in recent years.
The strictness of boats and ships desulfurization index is subjected to the restriction of specific environment on the ship again in the general industry desulfurization, and desulfurization research and development application technology peculiar to vessel and difficulty in process are very big, still belongs to blank so far at home and abroad.Take which kind of method desulfurization to decide with requiring the desulfurization index that reaches according to concrete operating mode.For desulfurization on the specific ship,,, require desulfuration efficiency to reach 70-80% at least for reaching the corresponding equivalent of sulfur-bearing 1.00%m/m if use used fuel oil (sulfur-bearing is less than 4.5%m/m); For reaching the corresponding equivalent of sulfur-bearing 0.10%m/m, require desulfuration efficiency to reach 97% at least.Because calcium method desulfuration efficiency is below 95%, magnesium method desulfuration efficiency can reach 99%, so have only the desulfurization of magnesium method can reach the SO of new standard correspondence
2The concentration of emission value.Consider that simultaneously the space is limited on the ship, do not allow device to account for a large amount of volumes, consumptive material or accessory substance bulk deposition,, can only adopt the method for abandoning in the desulfurization of magnesium base so simple seawater method and the desulfurization of calcium method are all inadvisable.Advantage such as the desulfurization of magnesium base has non-secondary pollution simultaneously, take that volume is little, non-scaling, operating cost are low, to sum up, magnesium base desulfur technology is the most practicable to desulfurization peculiar to vessel.Moreover, consider the boats and ships operating mode, seawater obtains easy fresh water and obtains difficulty on the ship, proposes magnesium base-seawater method desulfur technology and is used for the boats and ships desulfurization.The seawater method only adopts the desulfurization of magnesium base as a kind of householder method when boats and ships run on the fresh water district, be subjected to seawater corrosion in conjunction with the seawater method to avoid treating apparatus.Magnesium base-seawater method desulfur technology is a kind of effective desulfur technology that is applicable to the boats and ships specific operation, yet domestic and international this boats and ships desulfur technology belongs to blank.
Summary of the invention
For realizing that magnesium base-seawater method desulfur technology is applied to boats and ships flue gas high-efficiency desulfurization, the utility model provide a kind of can be reliably and with long-term, the magnesium base-seawater method desulphurization system peculiar to vessel of operation up to standard, the bunker oil sulfur content new standard that requires to carry out for China reply IMO is carried out solid technology and is prepared.
Principle of the present utility model is: through the sea water spray mist cooling, reduce to below 100 ℃, by multistage Mg (OH) by flue-gas temperature under blower fan drives for the boats and ships flue gas
2SO in slurry spraying and the flue gas
2Reaction reduces SO in the flue gas
2Concentration is to qualified discharge.Product MgSO
3Reduce to slurry pool with spray liquid, form MgSO by oxidation
4, discharge with draining.Inject the Mg (OH) of preparation according to certain flow
2Slurry is regulated slurry liquid pH value, guarantees high-efficiency desulfurization, replenishes new water, discharging reaction back spray liquid according to certain flow, keeps the slurry pool liquid level constant.
The technical solution of native system is achieved in that system mainly comprises desulfurizing tower, cooled with seawater sprayer unit, slurry tank, multi-stage spray device, seawater, be provided with slurry pool in described desulfurizing tower bottom, slurry pool top is the multi-stage spray device, by oxidation fan aerating oxygen in slurry pool, feed seawater by sea water pump in slurry pool, the slurry pool bottom is provided with excavationg pump; The top of described slurry tank is provided with steam, magnesia powder, seawater pipeline, wherein jet chimney is provided with electronic steam valve, seawater pipeline is provided with the seawater flow meter, be provided with agitator in the slurry tank, slurry tank lower end discharge pipe is provided with the frequency conversion tubing pump, also is provided with the slurry flow meter on the discharge pipe and is connected to the multi-stage spray device; The multi-stage spray device also is connected to slurry pool by spray pump; Boiler smoke enters the cooled with seawater sprayer unit through the smoke discharging pipe that is provided with electric butterfly valve, frequency conversion fan, flue gas flow meter successively, and the cooled with seawater sprayer unit is along the spraying of boiler smoke direction of ventilation, and the boiler smoke through cooling off enters desulfurizing tower; The desulfurizing tower top is provided with demist net and new water spray system, and flue gas enters chimney and discharge from the exhaust opening of desulfurizing tower after handling, and the exhaust opening sidewall is provided with SO
2The analyzer probe; Also be provided with pH meter, float type level gauge in the slurry pool.
Draw boiler smoke from flue collector,, show the air inducing air quantity by the flue gas flow meter by electric butterfly valve and frequency conversion fan interlock control air inducing; Pending boiler smoke enters the sea water spray mist cooling unit by the frequency conversion fan outlet, along boiler smoke direction of ventilation spraying, below the cooled flue gas temperature to 100 ℃, the auxiliary desulfidation that plays, and help boiler smoke air inducing, cooling fluid and the boiler smoke through cooling off together enter desulfurizing tower.Desulfurizing tower is provided with multi-stage spray device and the constant slurry pool about 1m of liquid level, and oxidation fan provides oxygen in slurry pool.Adopt spray pump to extract slurry circulation chilling spray in the slurry pool, circular response spray, form cooling fluid and spray liquid and drop to slurry pool under the gravity effect, the boiler smoke air-flow upwards finally is discharged in the atmosphere through exhaust opening demist net mist elimination.Drop into seawater and magnesia powder in the slurry tank in proportion, stir and the steam constant temperature heating through motor, quantitatively provide slurry from slurry tank lower end discharging opening branch multichannel to each spray piping by the frequency conversion tubing pump after the slaking, adopt valve and slurry flow meter accurately to control the slurry quantity delivered.Carry out with reaction, slurry pH descends gradually in the slurry pool, for guaranteeing high-efficiency desulfurization, determines the slurry pH excursion between the 6.5-11, is equipped with pH meter and monitors in real time.The slurry pool liquid level reduces gradually because of the evaporation in the flue gas cooling procedure simultaneously, the evaporated water in sidewall installation float type level gauge reflection cooling procedure.The slurry pool outer wall connects excavationg pump and sea water pump, according to slurry pH situation of change and application requirements, control excavationg pump flow and frequency are discharged reaction back waste liquid, the step control sea water pump of going forward side by side, replenish fresh seawater by certain flow and frequency, keep the slurry pool liquid level constant about 1m, have the function of regulating slurry pH concurrently.The desulfurizing tower top is provided with demist net and new water spray system, and the unlatching of measuring the new water spray system of control by flue gas flow is played the effect that replenishes new water simultaneously with timely cleaning demist net.The exhaust opening sidewall is provided with SO
2The analyzer probe is used for SO
2Concentration determination.SO according to discharging
2Concentration value changes slurry multi-stage spray device reaction progression, regulates the spray liquid flow by the frequency conversion spray pump, keeps SO
2Concentration is to qualified discharge.
The beneficial effects of the utility model are: realized that magnesium base-seawater method desulfur technology is applied to boats and ships flue gas high-efficiency desulfurization, can be reliably and with long-term, operation up to standard, and the bunker oil sulfur content new standard that requires to carry out for China reply IMO is carried out solid technology and is prepared.
Description of drawings
Below in conjunction with accompanying drawing and concrete embodiment the utility model is further described.
Fig. 1 is the utility model systematic schematic diagram.
Among the figure, 1, desulfurizing tower, 2, slurry tank, 3, chimney, 4, slurry pool, 5, seawater, 6, steam, 7, magnesia powder, 8, sea water pump, 9, the seawater flow meter, 10, motor-driven valve, 11, electronic steam valve, 12, frequency conversion tubing pump, 13, the slurry flow meter, 14, spray pump, 15, excavationg pump, 16, waste liquid, 17, oxidation fan, 18, boiler smoke, 19, electric butterfly valve, 20, frequency conversion fan, 21, the flue gas flow meter, 22, handle back gas.
The specific embodiment
Specify the utility model below in conjunction with embodiment.
Desulfurized effect was tested before and after real ship carried out the use of the utility model system on certain container ship, used sulfur-bearing 0.71~0.93%m/m fuel oil, normal sail, the about 50000m of main frame discharging waste gas air quantity
3/ h.Adopt 440V, 60Hz three-phase alternating current ship electricity power supply native system, the air inducing air quantity is less than 10000m
3/ h, air inducing power of fan are that 10~30kW is adjustable, and slurry frequency conversion pipeline pump power is adjustable less than 3kW, and pressure 3.5~4.0atm, slurry supply flow rate are 0.1~1.0m
3/ h is adjustable (Mg (OH)
2Slurry concentration is less than 25%).The circulated sprinkling pump power is that 10~30kW is adjustable, and slurry sprays less than 100m
3/ h is adjustable.In 10 hours, the continuous service test result sees the following form.
Annotate: slurry circulated sprinkling pump discharge value is the estimation gained.
Under test condition at that time, this ship successively uses sulfur-bearing 0.71%mm and two kinds of fuel oil of 0.93%m/m, because the mixing of two kinds of different fuel oil causes SO
2Initial concentration fluctuates in the scope of 240~320ppm.Provide the seawater method and adopt the experimental data of the magnesium base-seawater method of the utility model system to contrast.Data show that exhaust gas volumn increases, the final back SO that handles
2Concentration also increases thereupon; The circulated sprinkling amount is big more, handles back SO
2Concentration is more little.Simple employing seawater method desulfurization degree>70%, and the magnesium of the utility model system base-seawater method desulfurization degree>90%, latter's desulfurized effect obviously is better than the former as can be seen.This system applies on real ship, the SO after the desulfurization
2Content is lower than the Low Sulfur Fuel Oil of burning 0.10%, meets the requirement of bunker oil sulfur content new standard.This shows that this desulphurization system has significant reduction of discharging effect.
The utility model is not limited to the foregoing description, and protection domain of the present utility model is all classified in any equivalent concepts or change in the technical scope that the utility model discloses as.
Claims (1)
1. magnesium base-seawater method desulphurization system peculiar to vessel, it is characterized in that: mainly comprise desulfurizing tower (1), cooled with seawater sprayer unit, slurry tank (2), multi-stage spray device, seawater (5), be provided with slurry pool (4) in described desulfurizing tower (1) bottom, slurry pool (4) top is the multi-stage spray device, by oxidation fan (17) aerating oxygen in slurry pool (4), feed seawater by sea water pump (8) in slurry pool (4), slurry pool (4) bottom is provided with excavationg pump (15); The top of described slurry tank (2) is provided with steam (6), magnesia powder (7), seawater pipeline, wherein jet chimney is provided with electronic steam valve (11), seawater pipeline is provided with seawater flow meter (9), slurry tank is provided with agitator in (2), slurry tank (2) lower end discharge pipe is provided with frequency conversion tubing pump (12), also is provided with slurry flow meter (13) on the discharge pipe and is connected to the multi-stage spray device; The multi-stage spray device also is connected to slurry pool (4) by spray pump (14); Boiler smoke (18) enters the cooled with seawater sprayer unit through the smoke discharging pipe that is provided with electric butterfly valve (19), frequency conversion fan (20), flue gas flow meter (21) successively, the cooled with seawater sprayer unit is along the spraying of boiler smoke direction of ventilation, and the boiler smoke through cooling off enters desulfurizing tower (1); Desulfurizing tower (1) top is provided with demist net and new water spray system, and flue gas (22) enters chimney (3) and discharge from the exhaust opening of desulfurizing tower after handling, and the exhaust opening sidewall is provided with SO
2The analyzer probe; Slurry pool also is provided with pH meter, float type level gauge in (4).
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Cited By (12)
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CN102120138A (en) * | 2011-02-17 | 2011-07-13 | 大连海事大学 | Magnesium base-seawater method desulfurization system for ship |
CN104826476A (en) * | 2015-05-11 | 2015-08-12 | 武汉都市环保工程技术股份有限公司 | Industrial flue gas desulfurization/denitrification/dedusting integrated technique and device |
CN104998543A (en) * | 2015-06-30 | 2015-10-28 | 青岛海德威科技有限公司 | Ship exhaust gas treatment method and device |
US9387438B2 (en) | 2014-02-14 | 2016-07-12 | Tenneco Automotive Operating Company Inc. | Modular system for reduction of sulphur oxides in exhaust |
US11124714B2 (en) | 2020-02-19 | 2021-09-21 | Marathon Petroleum Company Lp | Low sulfur fuel oil blends for stability enhancement and associated methods |
CN115326147A (en) * | 2022-10-17 | 2022-11-11 | 江苏煵笙重工有限公司 | Real-time monitoring method and system for desulfurization tower for ship |
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Cited By (23)
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CN102120138B (en) * | 2011-02-17 | 2012-12-05 | 大连海事大学 | Magnesium base-seawater method desulfurization system for ship |
CN102120138A (en) * | 2011-02-17 | 2011-07-13 | 大连海事大学 | Magnesium base-seawater method desulfurization system for ship |
US9387438B2 (en) | 2014-02-14 | 2016-07-12 | Tenneco Automotive Operating Company Inc. | Modular system for reduction of sulphur oxides in exhaust |
CN104826476A (en) * | 2015-05-11 | 2015-08-12 | 武汉都市环保工程技术股份有限公司 | Industrial flue gas desulfurization/denitrification/dedusting integrated technique and device |
CN104998543A (en) * | 2015-06-30 | 2015-10-28 | 青岛海德威科技有限公司 | Ship exhaust gas treatment method and device |
US11891581B2 (en) | 2017-09-29 | 2024-02-06 | Marathon Petroleum Company Lp | Tower bottoms coke catching device |
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US11905479B2 (en) | 2020-02-19 | 2024-02-20 | Marathon Petroleum Company Lp | Low sulfur fuel oil blends for stability enhancement and associated methods |
US11905468B2 (en) | 2021-02-25 | 2024-02-20 | Marathon Petroleum Company Lp | Assemblies and methods for enhancing control of fluid catalytic cracking (FCC) processes using spectroscopic analyzers |
US11885739B2 (en) | 2021-02-25 | 2024-01-30 | Marathon Petroleum Company Lp | Methods and assemblies for determining and using standardized spectral responses for calibration of spectroscopic analyzers |
US11860069B2 (en) | 2021-02-25 | 2024-01-02 | Marathon Petroleum Company Lp | Methods and assemblies for determining and using standardized spectral responses for calibration of spectroscopic analyzers |
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CN115326147B (en) * | 2022-10-17 | 2023-11-24 | 江苏煵笙重工有限公司 | Real-time monitoring method and system for desulfurizing tower for ship |
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