FEEDER DEVICE FOR FEEDING AQUEOUS ACROLEIN SOLUTION TO A MAIN BALLAST WATER LINE OF A SHIP

Abstract

Feeder device for feeding aqueous acrolein solution to a main ballast water line of an apparatus for treating for an apparatus for shops for treating ballast water with acrolein comprises an annular nozzle which is dimensioned for usage in the main ballast water line, wherein the annular nozzle comprises a nozzle ring comprising a plurality of nozzle openings distributed over the interior circumference of the nozzle ring.

Description

BACKGROUND OF THE INVENTION

The invention pertains to a feeder device for feeding aqueous acrolein solution to a main ballast water line of an apparatus for treating for an apparatus for ships.

It is already known that ballast water can be disinfected on ships by use of acrolein. Already by adding 5 to 15 ppm acrolein to the ballast water, bacteria, algae, zebra mussels and other organisms of the zooplankton can be killed, and, thereby, the transfer from one port to another one can be surely eliminated. The advantage of the use of acrolein is the sustain ability in particular with respect to larvae of zebra mussels, and the fact that acrolein disintegrates by itself within a few days, i.e. no new burden of the port basin by this biocide is encountered upon discharging of the ballast water in the port of destination.

These advantages are accompanied by the fact that the handling, the transportation and the storage of pure acrolein cannot be carried out on ships because acrolein is a highly poisonous liquid doing the effects of teargas, and that the personnel on board would be forced to carry out the handling of this biocide only with a complete ABC protective clothing and using gasmasks.

Aqueous solutions of acrolein are not poisonous and can be safely handled, however, such solutions can only be handled during a few days such that the use on ships is impossible because of logistic problems.

From DE-GM 20 2007 004 912, a apparatus is known in which the ballast water is pumped by means of a pressure rising pump through a water jet pump, and the low pressure zone of the water jet pump is hydraulically connected via a control valve to a reaction container which has separate inlet openings for acrolein acetal, acid and hydrolysis water applied on the outside. In the reaction container, an aqueous acrolein solution is generated which is mixed to the ballast water in the water jet pump such that the organisms in the ballast water are killed by the acrolein. In the apparatus of DE-GM 20 2007 004 912, acrolein acetal can be used directly without a previous mixing with a solution agent being necessary. The same is true for the acid used as a catalyst which acid can be dosed into the apparatus without previous dissolution with water. The hydrolysis water is taken from the water apply system on board. Although the problem with the handling, the transport and the storage of pure acrolein on ships is solved in this apparatus, there are problems of the dimensioning, in particular of the water jet pump and the reaction container, with increasing requirements of throughput.

SUMMARY OF THE INVENTION

It is an object of the invention, to provide a feeder device for feeding aqueous acrolein solution to a main ballast water line of an apparatus for treating for an apparatus for ships which feeder device is simple in construction and adapted to treated ballast water with acrolein, where the usage of the feeder device is also guaranteed with large quantities of throughput with justifiable construction effort.

For achieving this objective, an inventive feeder device for feeding aqueous acrolein solution to a main ballast water line of an apparatus for treating for an apparatus for shops for treating ballast water with acrolein is characterized by an annular nozzle which is dimensioned for usage in the main ballast water line, wherein the annular nozzle comprises a nozzle ring comprising a plurality of nozzle openings distributed over the interior circumference of the nozzle ring. By means of the ring nozzle having a plurality of nozzle openings distributed over its interior circumference, the acrolein solution can be fed to this main ballast water stream simultaneously over the entire circumference of the main ballast water stream such that a unitary feeding of acrolein solution at the circumference of the main water stream is effected whereby a unitary and good mixing of the acrolein solution with the main ballast stream is made possible. A unitary mixing of the two streams is essential for the desired effect of the acrolein, i.e. killing of the living organisms in the main ballast water stream.

An advantageous embodiment of the inventive feeder device is characterized in that the plurality of the nozzle openings distributed over the interior circumference of the ring nozzle are arranged under equal distances whereby a uniform distribution of the acrolein solution streams in the main ballast water stream is obtained in an advantageous way.

A further advantageous embodiment of the inventive feeder device is characterized in that the interior diameter of the ring nozzle is adapted to the interior circumference of the main ballast water line of the main ballast water stream. Therein, it is advantageous that the main ballast water stream can flow unobstructed so that no solid components of the main ballast water stream can accumulate in front or behind the ring nozzle. Also, the lifetime of the ring nozzle is prolonged thereby.

A further advantageous embodiment of the inventive feeder device is characterized in that the feeding unit comprises additionally a flow interfering device arranged at the ring nozzle which stream interfering device is located downstream of the ring nozzle in direction of a main ballast water stream flowing in the main ballast water line. By means of the flow interfering device, the final mixing between the acrolein solution stream and the main ballast water stream is achieved in an advantageous way. That the fluid control device is formed separately from the ring nozzle has the advantage that the stream interfering device can be replaced easily when it is damaged or weared by the main ballast water stream.

A further advantageous embodiment of the inventive feeder device is characterized in that the flow interfering device comprises a mixing face plate having an opening for the main ballast water stream, wherein the opening has a smaller opening area than the free inner cross section area of the main ballast water line. The flow interfering device can be any flow guiding device, a diffuser or the like. The embodiment of the flow interfering device is a mixing face plate is a constructually simple and very efficient solution for the flow interfering device which ensures, at the one hand, the purpose of mixing the acrolein solution stream with the main ballast water stream and, on the other hand, is easily to be handled in case of a required exchange.

A further advantageous embodiment of the inventive feeder device is characterized in that the opening of the mixing face plate is not circular. The mixing function of the mixing face plate is improved by means of the non circular cross-section in comparison to the mixing effect of a mixing face plate having a round opening.

A further advantageous embodiment of the inventive feeder device is characterized in that the feeding line of the ring nozzle is formed as an injector line which is tangentially arranged at the ring nozzle. In this case, it is advantageous that the acrolein solution is introduced tangentially into the ring nozzle such that a circular stream is resulting in the ring nozzle which circular stream provides for a unitary distribution of the acrolein solution at the output openings of the ring nozzle.

A further understanding of the nature and advantages of the embodiments of the present invention may be realized by reference to the remaining portions of the specification and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows schematically a general outline of a ballast water treatment apparatus wherein the feeder device according to the invention may be installed,

FIG. 2 shows schematically a ring nozzle of the feeder device in side elevation,

FIG. 3 shows schematically a ring nozzle of the feeder device inserted into a ballast water tube line together with the mixing face plate,

FIG. 4 shows a perspective view of the ring nozzle of the feeder device with a tangentially arranged injector line,

FIG. 5 shows a front view of the mixing face plate MB having a rectangular opening, and

FIG. 6 shows a section of the mixing nozzle.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

FIG. 1 schematically shows an apparatus for treating ballast water with acrolein in which feeder device of the invention is employed. It is to be noted that the inventive feeder device may also be used independently from the total apparatus shown in FIG. 1.

As can be seen from FIG. 1, the main ballast water stream (volume/unit of time) BW of the ballast water to be treated with acrolein, flows through the main ballast water line 2 to a feeder device, a ring nozzle 4 with a nozzle ring 5 at the inside of which at least one nozzle opening 6, preferably a plurality of nozzle openings 6 arranged under equal spaces, are provided.

Furthermore, the feeding unit comprises a flow interfering device located downstream from the ring nozzle 4 as viewed in the direction of the main ballast water stream. The flow interfering device may be a restriction, a flow guiding device or another obstacle whereby the main ballast water stream coming from the ring nozzle, is whirled up and mixed thereby. A preferred shape of the flow interfering device is a mixing face plate 8 shown in FIG. 1 through which the ballast water flows which exits the ring nozzle 4. By means of the mixing face plate 8, the free cross-section of the main ballast water line 4 is narrowed down, and a hydraulic overpressure is generated in front of the face plate 8 which leads to a turbulence in the ballast water stream which leads to a fast and good mixing of the main ballast water stream BW with ballast water pretreated with acrolein.

A stream (volume/unit of time) BA of acrolein treated water flows simultaneously through the nozzle openings 6 to the inside and meets the main ballast water stream BW. The complete and instantaneous mixing of the main ballast water stream BW and the water stream BA pretreated with acrolein by means of the mixing face plate 8 provides, as a sum, the ballast water discharge stream BWB.

The apparatus comprises, furthermore, a branch line 10 branching off from the main ballast water line 2 downstream from the ballast water feed pump (not shown) through which ballast water is supplied to the ballast water tanks of the ship, and upstream of the feeder device and by which branch line a partial ballast water stream BT is supplied to the ballast water treatment apparatus. The branch line 10 leads to a separation unit 12 serving for the physical separation of the sludge portion and the suspended solid particles, respectively of the partial ballast water stream BT. A control valve 14 is provided in the branch line 10 in order to control the amount of the partial ballast water stream BT entering the separation unit 12. A sludge water stream BZ separated in the separation unit 12 leaves the apparatus through a discharge line 16. The separation unit 12 carries out a physical separation of suspended solid particles from the partial ballast water stream BT by means of a centrifugal force and/or filtration.

The partial ballast water stream BV which was previously physically cleaned by means of the separation unit 12, flows through a clear water line 18 to a suction port of a pressure rising pump 20. A pressurized water line 22 runs from the pressure rising pump 20 to the mixing nozzle 24 in order to supply the partial water stream BV which is coming from the pressure rising pump 20 and has previously been physically cleaned, to an input stub 26 of the mixing nozzle 24 in which the partial water stream BV is mixed with aqueous acrolein solution and diluted thereby such that the acrolein in the acrolein solution is not disintegrating.

The mixing nozzle 32 is a water jet pump with a nozzle area having a hydraulic overpressure. The mixing nozzle 24, furthermore, has a discharge stub 28 which is connected with the ring nozzle 4 via a line 29, and to vacuum stubs 30, 32.

The power of the pressure rising pump 20 is dimensioned depending on the narrowing down of the inlet cone of the mixing nozzle such that, with a nominal power of the pressure rising pump, a water stream flow speed of 20 to 25 m/sec is achieved in the area of the mixing nozzle between the inlet cone and the outlet cone. The pressure rising pump 20 is dimensioned to a power of 45 kW at a throughput of 500 m³/h and a flow speed of 2 to 3 m/sec in an inlet line and an outlet line of the pressure rising pump.

The mixing nozzle 24 has, furthermore, an outlet stub 28 which is connected with the ring nozzle 4 through a line 29, and to the vacuum stubs 30, 32. The pressure rising pump 20 is dimensioned such that, across the mixing nozzle 24, which is formed as a water jet pump, a pressure difference of about 1 to 1.5 bar between the pressure in the inlet stub 26 of the mixing nozzle 24 and the pressure in the discharge stub 28 of the mixing nozzle 24 is generated such that a vacuum region is created in the mixing nozzle by which vacuum the acrolein solution is sucked in.

The volume of the partial water stream BV is almost equal to the difference of the volume of the partial water stream BT sucked up by the pump, minus the volume of the sludge water stream BZ separated by the separation unit 12 by physical separation of solid material.

The one vacuum stub 30 is connected, via a line 34, with the hose reactor 36 comprising a discharge stub 38 and an input stub 40. The input stub 40 of the hose reactor 36 is connected, via a line 42, with the discharge stub 44 of the generator 46 which comprises an acrolein input stub 48, a disintegration catalyst input stub 50 and a water input stub 52.

A volume stream A of an acrolein derivative, for example acrolein acetal, is fed through the acrolein input stub 48 to the generator 46 depending on the volume of the partial water stream BT. A volume stream K of a disintegration catalyst is fed through the disintegration catalyst input stub 50 to the generator 46 depending from the volume stream A. A water stream W is fed through the water input stub 52 to the generator 46 depending on the volume stream A. A valve 56 for controlling the water intake is provided in a line 54 connected to the water input stub 53.

A branch line 58 runs from the water input stub 52 to the pressurized water line 22 and ends there in between the pump 20 and the mixing nozzle 24. If the valve 56 in the line 54 is open and the valve 60 in the line 58 is closed, the water is supplied from a clear water source (not shown). Alternatively, the generator 46 can also be operated through the line 58 with the partial stream of the partial water stream BV instead of with the water stream W. For this purpose, the valve 56 is closed and the valve 60 is opened.

The aqueous acrolein solution generated in the generator 46 by interaction of the water W, the disintegration catalyst K and the acrolein derivative A, flows from the discharge stub 44 of the generator 26 into the input stub 40 of the hose reactor 36 where the reaction of the reaction components is completed. The aqueous acrolein solution flows from the discharge stub 38 of the hose reactor 46 through the line 34 into the vacuum stub 30 of the mixing nozzle 32.

The volume stream of the aqueous acrolein solution supplied at the vacuum stub 30, meets the partial water stream BV supplied through the connection stub 36 and previously physically cleaned, in the mixing nozzle.

The acrolein containing water stream being generated in the mixing nozzle 24 leaves the mixing nozzle 24 through a discharge stub 28 and arrives through the line 29 at the ring nozzle 4 where the mixing with the main ballast water stream BW is carried out.

A tank 64 for dissolution accelerator is connected to the vacuum stub through a line 62. A pump 66 and a shutoff valve 68 are provided in the line 62 in this sequence between the tank 64 and the vacuum stub 32. The tank 64 is hydraulically connected through the line 63 to the suction stub of a pump 66. An input flange of the shutoff valve 68 is provided at the pressure stub of the pump 66. A discharge flange of the shutoff valve 68 is connected to the flange of the vacuum stub 32 of the mixing nozzle 24. Therefore, disintegration accelerator can be dosed from the tank 64, if needed by means of the pump 66 through the valve 68 through the line 62 to the vacuum stub 32.

FIG. 2 shows schematically a second embodiment of the apparatus. This embodiment differs from the first embodiment in that the water supply for the mixing nozzle 24 and the generator 46 is carried out from a separate water source, for example from the usage water supply of the ship which is shown by the usage water tank 67. The usage water tank 67 is directly connected with the pressure rising pump 20 in this embodiment. The common feature of the two embodiments consists in that an acrolein containing water stream which is small in comparison to the main ballast water stream is supplied to the main ballast water stream with a high efficiency.

As can be seen from FIG. 3, the nozzle ring 5 of the ring nozzle 4 consists out of an inner tube section 70 which is provided with a plurality of nozzle openings 6 on its circumference, as well as out of an outer tube ring 72 and to flange rings 74 and 76. The flange rings 74 and 76 are fluid tightly welded in between the inner tube section 70 and the outer tube section 72. Upstanding bolts 78 are inserted into the flange rings 74 and 76, the bolts having threats so that, with the aide of nuts 79 (FIG. 4), an easy installation in existing ballast water lines is possible.

As can be seen from FIG. 3, the ring nozzle 4 is directly connected through the upstanding bolts 78 and the nuts 79 to the connecting flanges 80, 82 of the main ballast water line 2 such that the mixing face plate 8 is located in flow direction of the main ballast water stream BW behind the nozzle openings. Flange seals 84, 86 are provided between the ring nozzle 4 and the connecting flanges 80, 82. The mixing face plate 8 is arranged between the ring nozzle 4 and the connecting flange 80 of the main ballast water line 2, and it is sealed by means of two flat sealings 88, 90. The mixing face plate 8 is simply clamped upon fastening the nuts 79 on the upstanding bolts 78. Thereby, an easy connection of the ring nozzle 4 into the ballast water lines present on the ship is obtained.

FIG. 4 shows the perspective view of the ring nozzle 4 and the line 29 tangentially arranged at the outer tube cover 72, which line 29 is arranged as injector line. The acrolein containing water stream which leaves the mixing nozzle 24 is under a pressure of about 1 to 1.5 bar such that the acrolein containing stream coming from the mixing nozzle 24 which is fed or injected under pressure in tangential direction through the line 29 into the nozzle ring of the ring nozzle 4 a circular stream is generated which insures that about the same amount of acrolein solution from the individual nozzle openings 6. Thereby, a unitary supply of acrolein solution into the main ballast water stream BW is done. The stream interfering device positioned downstream thereof, provides twirling and mixing of the acrolein solution with the main ballast water stream BW.

FIG. 5 shows, as preferred design of the stream interfering device, mixing face plate 8 having a non circular but rectangular opening 5. Thereby, the twirling and mixing, respectively, of the acrolein solution with the main ballast water stream is further improved as compared to a mixing plate having a circular opening.

FIG. 6 schematically shows a mixing nozzle 24. The mixing nozzle 24 comprises an outlet cone 94 and an inlet cone 96 as well as an intermediate piece 98 which is arranged between a flange 100 on the outlet end of the inlet cone 96 and a flange 102 at the input and of the output cone 94. The flanges 100, 102 and the intermediate piece 98 are tightened with each other by screws 104 and nuts 106, as is shown in FIG. 6. The inlet cone 96 comprises an inlet port 26 for blast water, and the outlet cone 94 comprises an outlet opening 28. The suction stubs 30 and 32 in the intermediate piece 98 serve to connect the line 34 for acrolein solution and the line 62 for disintegration accelerator, respectively.

As is shown in FIG. 6, the inlet cone 96 has an opening angle of 20 degrees and the outlet cone 94 has an opening angle of 10 degrees. The inlet cone 96 of the mixing nozzle 24 has a diameter ratio in flow direction S from the inlet to the outlet, i.e. a restriction of the diameter area, of about 2:1, and the outlet cone has a diameter ration in flow direction S from the inlet to the outlet, i.e. a widening of the opening area, of about 1:2. The diameter of the inlet cone 96 had its input 26 and the diameter of the outlet cone 94 at its output 28 has the same size as the diameter of the connected tube line for ballast water. When the pressure rising pump 20 is designed for 45 kW, and if the pressure rising pump 20 is operating at its nominal power, the required speed of flow of 20 to 25 msec at the outlet end of the inlet cone 96 is achieved with an average of 500 m³/h and a speed of flow of 2 to 3 msec.

The inlet cone 94 is connected to the ring nozzle 4 through a flange 98 with the supply line 29. The inlet stub 96 is connected through a flange 110 to the line 18 for the supply of ballast water.

It is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments will be apparent to those skilled in the art upon reviewing the above description. The scope of the invention should, therefore, be determined not as reference to the above description, but should instead be determined with reference to the appended claims along with the full scope of equivalence to which such claims are entitled.

Claims

1. Feeder device for feeding aqueous acrolein solution to a main ballast water line of an apparatus for treating for an apparatus for ships for treating ballast water with acrolein comprising an annular nozzle which is dimensioned for usage in the main ballast water line, wherein the annular nozzle comprises a ring nozzle comprising a plurality of nozzle openings distributed over the interior circumference of the ring nozzle.

2. Feeder device according to claim 1, wherein the plurality of the nozzle openings is distributed over the interior circumference of the ring nozzle are arranged under equal distances.

3. Feeder device according to claim 1, wherein the interior diameter of the ring nozzle is adapted to the interior circumference of the main ballast water.

4. Feeder device according to claim 1, wherein the feeding device comprises additionally a flow interfering device arranged at the ring nozzle which stream interfering device is located downstream of the ring nozzle in direction of a main ballast water stream flowing in the main ballast water line.

5. Feeder device according to claim 4, wherein the flow interfering device comprises a mixing face plate having an opening for the main ballast water stream, wherein the opening has a smaller opening area than the free inner cross section area of the main ballast water line.

6. Feeder device according to claim 5, wherein the opening of the mixing face plate is not circular.

7. Feeder device according to claim 1, wherein the feeding line of the ring nozzle is formed as an injector line which is tangentially arranged at the ring nozzle.