CN103007694B - Marine diesel engine exhaust seawater desulfurization device - Google Patents

Abstract

The invention relates to a seawater desulfurization device for tail gas of a marine diesel engine. The seawater desulfurization device comprises a shell, an air flow inlet flange, a tail liquid collecting tank, a tail liquid separator, a uniform air flow distributor, a turbulent flow ball layer, a parallel independent straight-pipe cross flow spraying device, a dehumidification device and an air flow outlet flange, wherein the air flow inlet flange is mounted at the bottom of the shell; the tail liquid collecting tank is mounted inside the shell and is located above the air flow inlet flange; the tail liquid separator is mounted inside the shell and is located above the tail liquid collecting tank; the uniform air flow distributor is mounted inside the shell and is located above the tail liquid separator; the turbulent flow ball layer is mounted inside the shell and is located above the uniform air flow distributor; the parallel independent straight-pipe cross flow spraying device is mounted inside the shell and is located above the turbulent flow ball layer; the dehumidification device is mounted in the shell and is located above the parallel independent straight-pipe cross flow spraying device; and the air flow outlet flange is mounted above the dehumidification device and is located at the top of the shell. According to the seawater desulfurization device, independent straight-pipe-type optimization is carried out on a spraying manner, the height, pressure loss and gas-liquid ratio of the desulfurization device are reduced on the premise of not increasing equipment and operation, and the desulfurization efficiency is effectively improved.

Description

Marine diesel engine exhaust seawater desulfurization device

technical field

The invention relates to a seawater desulfurization method and device for marine diesel engine tail gas, in particular to a parallel independent straight pipe cross-flow spray-turbulence ball marine diesel engine tail gas seawater desulfurization method and device to realize sulfur oxides in marine diesel engine tail gas removal.

Background technique

Marine fuel oil contains 0.1% to 7% sulfur. Due to the low sulfur content, the concentration of sulfur oxides in diesel engine flue gas is very low; but usually the ship has a long voyage distance and consumes a large amount of fuel oil, so the amount of sulfur oxides emitted by ships The total amount is huge. In order to prevent the air pollution caused by the emission of sulfur oxides caused by the operation of ships, the International Maritime Organization (IMO) has formulated Annex VI of the MARPOL Convention (Rules for the Prevention of Air Pollution Caused by Ships), which stipulates that ships must take measures to reduce the total emission of sulfur oxides The amount is reduced to 6.0g/(kw·h) or below. If the emission of sulfur oxides from marine diesel engine exhaust exceeds the standard, its navigation will be subject to the limits of the MARPOL73/78 Convention, resulting in huge economic losses. In order to reduce the emission of sulfur oxides during the operation of ships and meet the increasingly stringent requirements of the Convention, it is imperative to desulfurize the exhaust of marine diesel engines.

In the prior art, installing tail gas desulfurization devices on ships is the main means to ensure that the emission of sulfur oxides meets the standards. The seawater desulfurization process mainly uses the alkalinity of seawater to absorb and fix sulfur oxides. It has the advantages of relatively low construction and operation costs, no solid waste and sludge, no clogging and fouling of the desulfurization tower, small pressure loss, and stable operation. , the technical features meet the basic requirements of marine desulfurization devices.

The main equipment required for seawater desulfurization is the absorption tower. At present, most marine seawater absorption towers adopt the structure of spray tower and fixed packing tower, and adopt the two-phase countercurrent gas-liquid contact method. This point is currently recorded in many patents, including Invention Patent No. 201110177073.4 "Seawater Desulfurization Device for Marine Tail Exhaust Treatment System", Invention Patent No. 200810048002.2 "Sea Ship Smoke Desulfurization Method and Device", and Invention Patent No. 200710012371.1 "Devices for Seawater Washing Treatment of Ship Exhaust Gas and methods". Due to the low gas-liquid mass transfer rate in the absorption tower of the spray tower structure, seawater is prone to wall flow, resulting in insufficient gas-liquid contact and loss of desulfurization efficiency. The gas and liquid phases need to stay in the desulfurization device for a long time, so the tower height Huge and difficult to ship; in addition, the packed tower with fixed packing has a large pressure loss during operation, high energy consumption during operation, and wall flow phenomenon is also prone to occur. The liquid-gas ratio of these two types of desulfurization devices is relatively large. In order to obtain 95% desulfurization efficiency, the liquid-gas ratio of the plate spray tower is 10L/m ³ , and the liquid-gas ratio of the packed tower is 5.55L/m ³ . In summary, the defects such as excessive height of the desulfurization tower, large pressure loss, and large liquid-to-gas ratio limit the application of seawater desulfurization devices in marine diesel engine exhaust desulfurization.

The common way to overcome the above defects is to modify the seawater used as a sulfur oxide absorbent. This technical solution has been recorded in many patents, including the invention patent CN201210211165.4 "Electrolysis method for marine gas turbine exhaust treatment Seawater desulfurization method and device", and invention patent CN201110039565.7 "magnesium-seawater method marine desulfurization system". However, the seawater upgrading process requires the use of additional equipment or alkaline additives, and the operation is relatively complicated.

Contents of the invention

The purpose of the present invention is to provide a seawater desulfurization device for marine diesel engine tail gas, which can optimize the spray mode independently and straightly, and can reduce the height, pressure loss and gas-liquid ratio of the desulfurization device without increasing equipment and operations, and effectively improve Desulfurization efficiency.

In order to achieve the above object, the present invention provides a seawater desulfurization device for marine diesel engine exhaust, which includes a shell, an air inlet flange installed at the bottom of the shell, a tail liquid collection tank installed inside the shell and above the air inlet flange, installed on The tail liquid separator inside the shell and above the tail liquid collection tank, the air flow uniformizer installed inside the shell and above the tail liquid separator, the turbulent ball layer installed inside the shell and above the air flow even distributor, installed on Parallel independent straight-pipe cross-flow sprinklers inside the enclosure above the turbulent bulb, dehumidifiers mounted inside the enclosure above the parallel independent straight-pipe cross-flow sprinklers, and dehumidifiers mounted above the dehumidifier above the enclosure Airflow outlet flange on top.

The airflow inlet flange and the airflow outlet flange are respectively connected to the exhaust pipe flange of the ship, and the seawater desulfurization device is connected to the exhaust pipe of the ship.

The tail liquid separator adopts a cyclone tail liquid separator, which is fixedly installed on the inner wall of the shell through a bracket.

The bottom of the turbulent ball layer is equipped with a lower grid, which is located between the air flow uniformizer and the turbulent ball layer; the top of the turbulent ball layer is equipped with an upper grid, and the upper grid is located Between parallel independent straight-pipe cross-flow sprinklers.

The parallel independent straight pipe cross-flow spraying device comprises: a number of parallel independent straight pipes, which are arranged vertically in the radial direction in the shell of the seawater desulfurization device, and are uniformly distributed in the radial section of the seawater desulfurization device; Seawater pipes are arranged at intervals up and down, and each seawater pipe vertically passes through the shell and leads into the interior of the seawater desulfurization device, and vertically passes through each independent straight pipe into each independent straight pipe; several nozzles are respectively installed in each independent straight pipe Several levels of spraying devices are formed on each seawater pipe inside.

A seawater pipe flange is installed on one end of each seawater pipe outside the shell, which is connected with the seawater supply system.

The nozzle is installed vertically downward to the seawater pipe, and is located at the center of the cross section of each independent straight pipe; the spray angle α of the nozzle ranges from 15° to 180°, and the seawater sprayed by the nozzle is in the independent straight pipe. A hollow cone or a solid cone sea water curtain is formed inside the pipe.

The dehumidification device includes several cyclone dehumidifiers, which are respectively installed in each independent straight pipe and located above the topmost seawater pipe.

Several cyclone dehumidifiers can be set up and down in each independent straight pipe at intervals to form several stages of dehumidification devices.

The tail liquid collection tank is arranged around and covering the inner wall of the shell; a tail liquid discharge port is arranged on the shell at the lower part of the tail liquid collection tank, and a tail liquid discharge flange is provided at one end of the tail liquid discharge port for The desulfurization tail liquid receiving equipment is externally connected; a valve is also arranged between the tail liquid discharge port and the tail liquid discharge flange.

The seawater desulfurization device for marine diesel engine tail gas provided by the present invention has an independent straight-pipe optimization of the spraying mode, which can reduce the height, pressure loss and gas-liquid ratio of the desulfurization device without increasing equipment and operations, and effectively improve the desulfurization efficiency.

Description of drawings

Fig. 1 is the structural representation of marine diesel engine exhaust seawater desulfurization device among the present invention;

Fig. 2 is a schematic layout diagram of parallel independent straight pipes in the present invention.

Detailed ways

A preferred embodiment of the present invention will be described in detail below with reference to FIG. 1 and FIG. 2 .

As shown in FIG. 1 , it is a structural schematic diagram of a marine diesel engine exhaust seawater desulfurization device provided by the present invention. The seawater desulfurization device comprises a casing 18, an air inlet flange 1 installed at the bottom of the casing 18, a tail liquid collection tank 2 installed inside the casing 18 and above the air inlet flange 1, installed inside the casing 18 and positioned at the tail liquid collection The tail liquid separator 6 above the tank 2, the air flow uniformizer 8 installed inside the housing 18 and above the tail liquid separator 6, the turbulent ball layer 10 installed inside the housing 18 and above the air flow uniform distributor 8, installed The parallel independent straight-pipe cross-flow sprinkler installed inside the shell 18 and above the turbulent ball layer 10, the dehumidifier installed inside the shell 18 and above the parallel independent straight-pipe cross-flow sprinkler, and the dehumidifier installed on the dehumidifier Above and at the airflow outlet flange 17 at the top of the casing 18 .

The airflow inlet flange 1 and the airflow outlet flange 17 are connected to the exhaust pipe flange of the ship respectively, so as to connect the seawater desulfurization device into the exhaust pipe of the ship.

The tail liquid separator 6 adopts a cyclone type tail liquid separator, and is fixedly installed on the inner wall of the shell 18 through the bracket 7 .

The bottom of the turbulent ball layer 10 is equipped with a lower grid 9, which is located between the air flow uniform device 8 and the turbulent ball layer 10; the top of the turbulent ball layer 10 is equipped with an upper grid 11, the The upper grid 11 is located between the turbulent ball layer 10 and the parallel independent straight pipe cross-flow spraying device.

The parallel independent straight pipe cross-flow spraying device includes several parallel independent straight pipes 12, as shown in Figure 2, several independent straight pipes 12 are vertically arranged radially in the shell 18 of the seawater desulfurization device, and in The seawater desulfurization device is evenly distributed in the radial section.

The parallel independent straight pipe cross-flow spraying device also includes several seawater pipes 14, which are distributed at intervals up and down. Each seawater pipe 14 vertically passes through the shell 18 and is introduced into the interior of the seawater desulfurization device, and vertically passes through each independent straight pipe 12 respectively. Each independent straight pipe 12 is introduced into the interior; a seawater pipe flange 15 is installed on one end of each seawater pipe 14 outside the shell 18, which is connected with the seawater supply system.

The parallel independent straight pipe cross-flow spraying device also includes a number of spray heads 13, which are respectively installed on each seawater pipe 14 inside each independent straight pipe 12, thereby forming a one-stage or multi-stage spraying device; the spray heads 13 is installed vertically downward to the seawater pipe 14, and is located at the center of the cross-section of each independent straight pipe 12; the spray angle α of the nozzle 13 ranges from 15° to 180°, and the seawater sprayed by the nozzle 13 is in the A hollow cone or a sea water curtain 19 of a solid cone is formed inside the independent straight pipe 12 .

The dehumidification device includes several cyclone dehumidifiers 16, which are respectively installed in each independent straight pipe 12, and are located above the topmost seawater pipe 14. Further, a plurality of cyclone dehumidifiers 16 can be set up and down in each independent straight pipe 12 at intervals, thereby forming a multi-stage dehumidification device.

The tail liquid collection tank 2 is arranged around and covering the inner wall of the shell 18; a tail liquid discharge port 3 is provided on the shell 18 at the bottom of the tail liquid collection tank 2, and a tail liquid discharge port 3 is provided at one end of the tail liquid discharge port 3. The discharge flange 5 is used to externally connect the desulfurization tail liquid receiving equipment, and a valve 4 is also arranged between the tail liquid discharge port 3 and the tail liquid discharge flange 5 .

The specific desulfurization process and method of the marine diesel engine exhaust seawater desulfurization device provided by the present invention are as follows. First, the air inlet flange 1 and the air outlet flange 17 are docked and fixed with the corresponding flanges of the exhaust pipe of the ship, so that the marine diesel engine exhaust seawater desulfurization device is connected to the exhaust pipe of the ship, and the exhaust gas of the marine diesel engine follows the airflow direction shown in Figure 1 It enters the interior of the seawater desulfurization device from the air inlet flange 1. The marine diesel engine exhaust gas first passes through the swirl type tail liquid separator 6, driving the swirl type tail liquid separator 6 to rotate; and further passes through the airflow uniformity device 8, so that the marine diesel engine exhaust gas flow that is about to enter the turbulent spherical layer 10 is desulfurized by the coastal water desulfurization device uniform radial distribution. Subsequently, when the marine diesel engine exhaust gas flow enters the turbulent ball layer 10, the blown turbulent balls perform turbulent motion between the upper grille 9 and the lower grille 11, and a gas-liquid mass transfer process occurs on the surface of the turbulent balls. Next, the exhaust gas flow of the marine diesel engine enters the independent straight pipes 12 respectively. Since the seawater pipe flange 15 is externally connected to the seawater supply system, the seawater enters the nozzle 13 through the seawater pipe 14, and is sprayed from the nozzle 13 to the inner wall of the independent straight pipe 12 to form a seawater water curtain 19. , so that the gas-liquid mass transfer process occurs between the seawater and the exhaust gas flow of the marine diesel engine passing through the seawater water curtain 19, and the sulfur oxides in the exhaust gas flow of the marine diesel engine are removed. Finally, the air flow is dehumidified through the cyclone dehumidifier 16 to remove the water vapor in the air flow after desulfurization, and is discharged from the air flow outlet flange 17 into the exhaust pipe of the ship.

In the above process, most of the seawater droplets that have undergone gas-liquid mass transfer with the exhaust gas flow of the marine diesel engine move downward under the action of gravity or form a downward wall flow on the inner wall of each independent straight pipe 12 and enter the turbulent spherical layer 10. The gas-liquid mass transfer process occurs between the surface of the ball and the subsequent inflow of marine diesel engine exhaust gas flow. In addition, a small part of seawater droplets is entrained by the airflow into the cyclone dehumidifier 16, and is dehumidified and separated from the airflow by the cyclone dehumidifier 16, thereby forming a downward wall flow on the inner wall of each independent straight pipe 12 and entering the turbulent ball Gas-liquid mass transfer occurs between the layer and the subsequent inflowing gas flow. Finally, all the seawater droplets form the desulfurization tail liquid after passing through the turbulent spherical layer 10 downwards. When the desulfurization tail liquid continues to move downward and pass through the tail liquid separator 6, it is separated from the subsequent flow of marine diesel engine exhaust gas flow, and is discharged in the shell. The inner wall of 18 forms a downward wall flow so as to enter the tail liquid collection tank 2. When the liquid level of the desulfurized tail liquid collected in the tail liquid collection tank 2 is lower than the upper edge of the tail liquid discharge port 3, the valve 4 remains closed to prevent the subsequent inflow of the undesulfurized marine diesel exhaust gas flow from the tail liquid discharge port 3 ; and when the liquid level of the desulfurization tail liquid collected in the tail liquid collection tank 2 is higher than the upper edge of the tail liquid discharge port 3, the valve 4 is opened, and the desulfurization tail liquid is discharged from the tail liquid discharge port 3 to the tail liquid discharge flange 5 In the external desulfurization tail liquid receiving equipment.

To sum up, compared with the prior art, the marine diesel engine exhaust seawater desulfurization device provided by the present invention has the following advantages and beneficial effects.

1. In the parallel independent straight-pipe cross-flow spraying device, the cross-flow movement of tail gas flow and seawater improves the gas-liquid mass transfer rate, overcomes the negative impact of wall flow on desulfurization efficiency, reduces the tower height of the absorption tower, and reduces the pressure loss.

2. In the parallel independent straight pipe cross-flow spraying device, the independent straight pipe structure is adopted to reduce the unevenness of gas-liquid distribution, increase the probability of gas-liquid contact, and improve the desulfurization efficiency.

3. During the operation of the exhaust gas flow, the turbulent spherical layer maintains a turbulent state, reduces the pressure loss, increases the gas-liquid contact probability and contact time, and improves the absorption efficiency.

4. Both the dehumidifier and the tail liquid separator adopt the swirling flow type to reduce the pressure loss and make the desulfurization tail liquid form a wall flow.

5. In addition, a tail liquid collection tank 2 is provided to effectively collect the desulfurization tail liquid forming a wall flow. The structure is simple and not easy to damage; and a valve is set to prevent the untreated tail gas flow from leaking out from the tail liquid outlet.

Therefore, the seawater desulfurization device for marine diesel engine exhaust provided by the present invention has a desulfurization efficiency of not less than 90%, an overall height of the device not higher than 2m, a pressure loss not higher than 300mmHg, and a liquid-gas ratio not higher than 4L/m ³ .

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as limiting the present invention. Various modifications and alterations to the present invention will become apparent to those skilled in the art upon reading the above disclosure. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims (8)

1. a marine diesel tail gas seawater desulfurization device, is characterized in that, comprises:

Shell (18);

Be arranged on the air flow inlet flange (1) of shell (18) bottom;

Be arranged on shell (18) inner and be positioned at the tail washings feeder (2) of air flow inlet flange (1) top

Be arranged on shell (18) inner and be positioned at the tail washings separator (6) of tail washings feeder (2) top;

Be arranged on shell (18) inner and be positioned at the air-flow even distributor (8) of tail washings separator (6) top;

Be arranged on shell (18) inner and be positioned at the turbulence sphere layer (10) of air-flow even distributor (8) top;

Be arranged on shell (18) inner and be positioned at the independent straight tube cross-current type of the parallel connection spray equipment of turbulence sphere layer (10) top;

Be arranged on shell (18) inner and be positioned at the dehydrating unit of independent straight tube cross-current type spray equipment in parallel top; And

Be arranged on dehydrating unit top and be positioned at the air stream outlet flange (17) at shell (18) top;

Wherein, described tail washings separator (6) adopts spiral-flow type tail washings separator, by support (7), is fixedly mounted on the inwall of shell (18);

The bottom of described turbulence sphere layer (10) is provided with Under The Grille (9), and this Under The Grille (9) is positioned between air-flow even distributor (8) and turbulence sphere layer (10); The top of described turbulence sphere layer (10) is provided with grid (11), and grid on this (11) is positioned between turbulence sphere layer (10) and independent straight tube cross-current type spray equipment in parallel.

2. marine diesel tail gas seawater desulfurization device as claimed in claim 1, is characterized in that, described air flow inlet flange (1) is connected with boats and ships blast pipe flange respectively with air stream outlet flange (17), and seawater desulfurization device is accessed in boats and ships blast pipe.

3. marine diesel tail gas seawater desulfurization device as claimed in claim 1, is characterized in that, the independent straight tube cross-current type of described parallel connection spray equipment comprises:

The independent straight tube (12) of some parallel connections radially vertically arranges respectively, and is uniformly distributed in the radial section of this seawater desulfurization device in the shell (18) of seawater desulfurization device;

Some seawater pipes (14), spaced apart up and down, every seawater pipe (14) is vertically introduced seawater desulfurization device inside and vertically through each independent straight tube (12), introduces each independent straight tube (12) inside respectively through shell (18);

Some shower nozzles (13), it is upper that it is arranged on respectively the inner every seawater pipe (14) of each independent straight tube (12), forms some grades of spray equipments.

4. marine diesel tail gas seawater desulfurization device as claimed in claim 3, is characterized in that, at every seawater pipe (14), is positioned on the outside one end of shell (18) seawater pipe flange (15) is installed, and it is connected with sea water supply system.

5. marine diesel tail gas seawater desulfurization device as claimed in claim 3, is characterized in that, described shower nozzle (13) is installed downwards perpendicular to seawater pipe (14), and is positioned at the place, the cross section center of circle of each independent straight tube (12); The angular range of the spray angle of described shower nozzle (13) is 15 °～180 °, and the seawater being sprayed by this shower nozzle (13) is at the inner seawater water curtain (19) that forms conulite or solid conical of independent straight tube (12).

6. marine diesel tail gas seawater desulfurization device as claimed in claim 1, is characterized in that, described dehydrating unit comprises some spiral-flow type dehumidifiers (16), is arranged on respectively in each independent straight tube (12), and is positioned at the top of top seawater pipe (14).

7. marine diesel tail gas seawater desulfurization device as claimed in claim 6, is characterized in that, in each independent straight tube (12), can, between the upper and lower every several spiral-flow type dehumidifiers (16) are set, form some grades of dehydrating units.

8. marine diesel tail gas seawater desulfurization device as claimed in claim 1, is characterized in that, described tail washings feeder (2) is around the also inwall setting of covering shell (18);

On the shell (18) of described tail washings feeder (2) bottom, be provided with tail washings outlet (3), in one end of this tail washings outlet (3), be provided with tail washings and discharge flange (5), for external desulfurization tail washings receiving equipment;

Between described tail washings outlet (3) and tail washings discharge flange (5), be also provided with valve (4).