JP6652971B2 - Ballast water treatment apparatus and ballast water treatment method - Google Patents

Description

  The present invention relates to a ballast water treatment device and a ballast water treatment method.

  BACKGROUND ART Conventionally, in order to stabilize a ship such as a cargo ship in a state where no cargo is loaded, a countermeasure for filling seawater as ballast water into a ballast tank arranged in the ship has been known. Here, in seawater used as ballast water, there are many microorganisms, fungi, and the like. Therefore, when discharging ballast water from a ship that travels between foreign countries, it is necessary to sterilize ballast water in order to prevent the effects of microorganisms and fungi on the marine ecosystem.

  Examples of the method of disinfecting ballast water include a method of introducing a chemical agent and a method of irradiating ultraviolet rays. Patent Document 1 listed below discloses a device in which a bypass pipe is connected in the middle of a main pipe connected to a ballast tank, and a disinfectant supply device is arranged in the bypass pipe. In this device, a part of the raw water flowing through the main pipe is flowed to the bypass pipe side, and a germicide solution is obtained by dissolving the germicide therein, and the germicide solution is combined with the raw water flowing through the main pipe by The ballast water is sterilized.

  In Patent Literature 1 below, raw water of ballast water taken into a ship is used as a solution for dissolving a bactericide as it is, but the raw water has unstable water temperature and water quality. On the other hand, the dissolution behavior of the disinfectant greatly varies depending on not only the flow rate of the raw water but also the water temperature and water quality (salt content and turbidity). For this reason, as in Patent Document 1 below, when raw water taken into a ship is directly used as a dissolution solution without being stored in the ship, the dissolution behavior of the disinfectant is not stable due to the influence of water temperature and water quality, It is difficult to control the chemical concentration of ballast water within a target range.

JP 2012-254402 A

  An object of the present invention is to provide a ballast water treatment apparatus and a ballast water treatment method that can easily control the chemical concentration of ballast water to a desired range.

A ballast water treatment apparatus according to one aspect of the present invention is a dissolving means for dissolving a disinfectant in shipboard water stored in a ship, and disinfectant solution obtained by the dissolving means, for guiding ballast water to a ballast tank. And an injecting means for injecting into the piping of (1). The dissolving means includes a spare tank for storing water pumped into the ship before filling the ballast tank. The inboard water is water stored in the spare tank.

A ballast water treatment method according to another aspect of the present invention is a ballast water treatment method for guiding sterilized ballast water to a ballast tank. This ballast water treatment method stores ballast water in a spare tank in a ship as tank storage water before filling the ballast tank, and dissolves a disinfectant in the tank storage water when filling the ballast tank. the disinfectant solution was prepared by, including, and that the sterilizing treatment by injecting the disinfectant solution to the ballast water to be guided to the ballast tank.

It is a schematic diagram showing the composition of the ballast water treatment equipment concerning Embodiment 1 of the present invention. It is the schematic which shows the structure of the ballast water treatment apparatus which concerns on Embodiment 2 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
[Ballast water treatment equipment]
First, a configuration of a ballast water treatment device 1 according to Embodiment 1 which is an embodiment of the present invention will be described with reference to FIG.

  The ballast water treatment device 1 is a device that is disposed in a ship, sterilizes ballast water pumped into the ship, and guides the ballast water to a ballast tank 60. The ballast water treatment apparatus 1 includes a pipe 11, a ballast pump 10, a filter 20, a filtering member, a dissolving unit 30, an injection unit 40, a concentration measuring unit 90, a mixer 50, a temperature measuring unit 70, And a flow control unit 80.

  The pipe 11 is connected to the ballast tank 60, and constitutes a supply flow path for guiding ballast water pumped into the ship to the ballast tank 60. The pipe 11 has one pipe port into which ballast water flows, and the other pipe port connected to the ballast tank 60. The ballast water flows into the pipe 11 from the one pipe port, and is guided to the ballast tank 60 by flowing through the pipe 11 toward the other pipe port. The ballast water is stored in the ballast tank 60 for stabilizing the hull.

  The ballast pump 10 is arranged on the pipe 11 on one side of the pipe opening, and allows ballast water to flow into the pipe 11. The filter 20 is disposed downstream of the ballast pump 10 in the flow direction of the ballast water (the ballast tank 60 side) in the pipe 11. The filter 20 removes foreign substances and the like contained in the ballast water by filtration. In addition, the filter 20 may be arranged on the upstream side with respect to the ballast pump 10.

  The dissolving means 30 prepares a disinfectant solution S in which the disinfectant 3 is dissolved in inboard water stored in the ship. The dissolving means 30 has a chemical container 31 filled with the germicide 3, an inboard tank 33 for storing inboard water, and a connection pipe 32 for connecting the chemical container 31 and the inboard tank 33.

  A housing member (not shown) for housing the germicide 3 is disposed inside the chemical container 31. The storage member has a shape such as a mesh or a screen, for example, and has an opening for storing the germicide 3 and allowing sufficient flow of water flowing into the chemical container 31. Thereby, the disinfectant 3 can be dissolved in the water flowing into the chemical container 31.

  The disinfectant 3 is a solid drug composed of isocyanuric acid chloride. Here, “isocyanuric acid chloride” is a compound having a structure in which a hydrogen atom bonded to a nitrogen atom of isocyanuric acid is replaced with a chlorine atom, and trichloroisocyanuric acid in which a hydrogen atom is replaced by three chlorine atoms. It includes an acid (the following structural formula (1)) and sodium dichloroisocyanurate in which a hydrogen atom is substituted by two chlorine atoms (the following structural formula (2)). These isocyanuric acid chlorides generate hypochlorite (HOCl) having disinfecting properties by dissolving in water.

  The fungicide 3 may have a form such as a granule or a tablet, but is not particularly limited. For example, the disinfectant 3 may have a granular or tablet form having a diameter of 1 to 100 mm.

  The filling amount of the germicide 3 is determined as follows. First, the amount of ballast water stored in the ballast tank 60 and its chlorine concentration are set, and the amount of the disinfectant 3 necessary to secure the set amount of ballast water and chlorine concentration is calculated. Then, the disinfectant 3 is filled in the medicine container 31 in an amount equal to or greater than the calculated amount. Here, the amount of the disinfectant 3 according to the amount of ballast water stored in the ballast tank 60 is calculated, for example, as follows. Assuming that the amount of ballast water stored in the ballast tank 60 is 1000 tons, the set value of chlorine concentration is 10 mg / L, and the concentration of the disinfectant 3 necessary to make the chlorine concentration 10 mg / L is 12 mg / L, 12 (mg / L) L) × 1000 (ton) × 1000 (L / ton) = 12 kg, and the amount of the fungicide 3 can be calculated.

  Living water used in the ship is stored in the onboard tank 33 as inboard water. The water for domestic use is water supplied from the land to the ship while the ship is anchored, and is used for life on the ship such as hand washing, showers, toilets, and laundry. The above-mentioned domestic water is not seawater and does not contain salt. The above-mentioned domestic water is stored in the onboard tank 33, so that the water temperature falls within a certain range close to the room temperature inside the boat.

  The inboard tank 33 is a dedicated tank for storing the above-mentioned domestic water, and a part of the water may be used as a solvent for dissolving the disinfectant 3. The inboard tank 33 is a tank provided separately from the dedicated tank, and may store a part of water transferred from the dedicated tank.

  The water flowing out of the inboard tank 33 flows into the chemical container 31 via the connection pipe 32. At this time, the disinfectant 3 is dissolved in water to generate hypochlorous acid, and the disinfectant solution S is prepared. Then, the germicide solution S flows out of the chemical container 31. As described above, in the present embodiment, the amount of the disinfectant 3 dissolved is stabilized by using, as the solvent for the disinfectant 3, the domestic water stored in the onboard tank 33 and having a water temperature within a certain range as a solvent for the disinfectant 3, A germicide solution S adjusted to a desired drug concentration can be obtained.

  The injection means 40 injects the disinfectant solution S prepared by the dissolving means 30 into the pipe 11. The injection means 40 has a supply pipe 41 and a liquid sending pump 42. The supply pipe 41 has one end connected to the chemical container 31 and the other end connected to a portion P <b> 1 of the pipe 11. That is, the supply pipe 41 is a pipe branched from the portion P1 of the pipe 11. The portion P1 is located downstream of the filter 20 and upstream of the mixer 50 in the pipe 11, as shown in FIG.

  The liquid sending pump 42 is provided in the supply pipe 41 and adjusts the flow rate of the germicide solution S injected into the pipe 11. The flow rate of the germicide solution S flowing out of the chemical container 31 is adjusted by the liquid sending pump 42, and injected into the ballast water in the pipe 11 via the supply pipe 41. Thereby, the ballast water in the pipe 11 is sterilized.

  The mixer 50 is disposed downstream of the portion P1 in the pipe 11. The mixer 50 stirs the ballast water after the disinfectant solution S has been injected by the injection means 40, thereby uniformizing the chlorine concentration in the ballast water.

  The concentration measuring section 90 is disposed downstream of the mixer 50 and upstream of the ballast tank 60 in the pipe 11. The concentration measuring section 90 is a concentration measuring instrument, and measures the chlorine concentration of the ballast water after the disinfectant solution S is injected and stirred by the mixer 50. Here, the “chlorine concentration (mg / L)” is measured as the concentration of residual oxidant (TRO: Total Residual Oxidant) in ballast water.

  The temperature measuring unit 70 is a water thermometer, and is attached to the tank 33 in the boat. The temperature of the inboard water stored in the inboard tank 33 is measured by the temperature measuring unit 70.

  The flow control unit 80 adjusts the flow rate of the germicide solution S injected into the pipe 11 by the injection unit 40. The flow control unit 80 is configured by, for example, a personal computer including an arithmetic unit and a storage unit. The flow controller 80 is connected to the liquid pump 42, and controls the operation of the liquid pump 42 to adjust the flow rate of the sterilant solution S to the pipe 11.

  The flow control unit 80 is connected to the concentration measuring unit 90, and receives a measurement result by the concentration measuring unit 90. The flow control unit 80 controls the operation of the liquid sending pump 42 based on the input result of the concentration measurement. Thereby, the injection flow rate of the germicide solution S into the pipe 11 is adjusted. More specifically, when the chlorine concentration of the ballast water measured by the concentration measuring unit 90 exceeds a predetermined reference range, the flow control unit 80 sends the injection flow of the disinfectant solution S so as to decrease. The operation of the liquid pump 42 is controlled. On the other hand, when the chlorine concentration of the ballast water is lower than the reference range, the flow control unit 80 controls the operation of the liquid feed pump 42 so that the injection flow rate of the disinfectant solution S increases. The storage unit of the flow rate control unit 80 stores data indicating the reference range of the chlorine concentration of the ballast water for comparison with the concentration measurement data as described above.

  The flow control unit 80 is connected to the temperature measurement unit 70, and receives a measurement result from the temperature measurement unit 70. The flow controller 80 controls the operation of the liquid feed pump 42 based on the input result of the temperature measurement. Thereby, the injection flow rate of the germicide solution S into the pipe 11 is adjusted. More specifically, in consideration of the fact that the amount of disinfectant 3 to be dissolved varies depending on the water temperature, the flow control unit 80 presets the injection flow rate of the disinfectant solution S for each water temperature. Then, the flow control unit 80 controls the operation of the liquid feed pump 42 so that the flow rate of the disinfectant solution S injected into the pipe 11 is adjusted to the injection flow rate corresponding to the input water temperature data.

[Ballast water treatment method]
Next, a ballast water treatment method according to the present embodiment, which is performed using the ballast water treatment device 1, will be described.

  First, by operating the ballast pump 10, seawater is pumped into the pipe 11 as ballast water. The pumped ballast water is filtered by the filter 20 to remove foreign substances and the like, and is guided to the ballast tank 60 through the pipe 11.

  On the other hand, domestic water is stored in the inboard tank 33 as inboard water, and the water temperature is within a certain range. The domestic water flows into the chemical container 31 from the tank 33 on the ship via the connection pipe 32. Then, the disinfectant solution S is obtained by dissolving the disinfectant 3 in water.

  Thereafter, the disinfectant solution S is guided to the pipe 11 through the supply pipe 41 and injected into ballast water guided to the ballast tank 60. At this time, the injection flow rate of the germicide solution S is adjusted by the liquid sending pump 42. By injecting the disinfectant solution S in this manner, the ballast water is disinfected. Then, the ballast water is stirred in the mixer 50 to make the chlorine concentration uniform and stored in the ballast tank 60.

  Further, in the above ballast water filling, the chlorine concentration of the ballast water after being stirred by the mixer 50 is periodically measured by the concentration measuring unit 90, and the measurement result is input to the flow control unit 80. The flow control unit 80 compares the input concentration data with the reference range, does not change the operation of the liquid sending pump 42 when the concentration data is within the reference range, and when the concentration data is outside the reference range. The operation of the liquid feed pump 42 is changed. More specifically, when the concentration data exceeds the reference range, the operation of the liquid sending pump 42 is changed so that the injection flow rate of the disinfectant solution S is reduced. The operation of the liquid feed pump 42 is changed so that the injection flow rate of S increases. As described above, by measuring the chlorine concentration in the ballast water filling water and feeding back the measurement result to the injection flow rate of the disinfectant solution S, the chlorine concentration of the ballast water can be adjusted to an appropriate value.

  Prior to the start of the ballast water filling, the temperature of the domestic water stored in the onboard tank 33 is measured in advance by the temperature measuring unit 70, and the injection flow rate of the disinfectant solution S at the beginning of the filling start based on the measurement result. May be adjusted. More specifically, with reference to the injection amount of the disinfectant solution S set for each water temperature, the flow control unit 80 controls the operation of the liquid sending pump 42 so that the injection flow rate corresponds to the measured water temperature data. Controlled. Thereby, even in the initial stage of the start of filling, the chlorine concentration of the ballast water can be adjusted to an appropriate value.

[Effects]
Next, the features of the ballast water treatment apparatus 1 and the ballast water treatment method and the effects thereof will be described.

  The ballast water treatment apparatus 1 includes a dissolving unit 30 for dissolving the disinfectant 3 in domestic water (inboard water) stored in the ship, and a disinfectant solution S obtained by the dissolving unit 30. And an injecting means 40 for injecting into the pipe 11 for guiding the water. Further, the ballast water treatment method is a method for guiding the sterilized ballast water to the ballast tank 60, and the disinfectant solution S is prepared by dissolving the disinfectant 3 in the domestic water stored in the ship. The sterilization treatment is performed by injecting the disinfectant solution S into ballast water guided to the ballast tank 60.

  According to the above feature, the ballast water can be sterilized by injecting the disinfectant solution S in which the disinfectant 3 is dissolved in the domestic water stored in the ship into the pipe 11. Since this domestic water is stored on board, the water temperature is within a certain range. For this reason, the fluctuation | variation of the dissolution behavior of the disinfectant 3 can be suppressed compared with the case where the raw water whose water temperature is unstable immediately after being taken in a ship is used as a dissolution liquid as it is. As a result, the chlorine concentration of the ballast water can be easily controlled to a desired range. In particular, by using domestic water having a stable water temperature and quality as shipboard water, fluctuations in the dissolution behavior of the disinfectant 3 can be more effectively suppressed.

  The ballast water treatment apparatus 1 includes a concentration measuring section 90 for measuring the chlorine concentration of the ballast water into which the disinfectant solution S has been injected, and a disinfectant injected by the injection means 40 based on the measurement result by the concentration measuring section 90. A flow control unit 80 that adjusts the flow rate of the solution S. In the above ballast water treatment method, the chlorine concentration of the ballast water into which the disinfectant solution S has been injected is measured, and the injection flow rate of the disinfectant solution S is adjusted based on the measurement result. As described above, the chlorine concentration of the ballast water after the sterilization treatment is measured, and the measurement result is fed back to the injection flow rate of the disinfectant solution S, whereby the chlorine concentration of the ballast water can be adjusted to an appropriate value. Thereby, while maintaining the sterilizing effect, the corrosion of the pipe 11 and the ballast tank 60 due to the excessive chlorine concentration can be suppressed.

  The ballast water treatment device 1 includes a temperature measurement unit 70 that measures the temperature of domestic water in the onboard tank 33, and a flow rate of the disinfectant solution S injected by the injection unit 40 based on the measurement result by the temperature measurement unit 70. And a flow control unit 80 that adjusts the flow rate. In the above ballast water treatment method, the temperature of domestic water in the inboard tank 33 is measured, and the injection flow rate of the disinfectant solution S is adjusted based on the measurement result. The dissolution behavior of the germicide 3 changes depending on the water temperature. For this reason, the temperature of the above-mentioned domestic water is measured by the temperature measuring section 70, and the measurement result is fed back to the flow rate of the disinfectant solution S, whereby the chlorine concentration of the ballast water can be adjusted to an appropriate value.

  In the ballast water treatment device 1 and the ballast water treatment method, the germicide 3 may be trichloroisocyanuric acid. Since trichloroisocyanuric acid has relatively low solubility in water, it can maintain a bactericidal effect for a long period of time. Further, it can be stably maintained at a high temperature. Further, unlike calcium hypochlorite, etc., the generation of precipitates when dissolved in water can also be suppressed. Therefore, trichloroisocyanuric acid can be suitably used as the fungicide 3.

(Embodiment 2)
Next, a second embodiment, which is another embodiment of the present invention, will be described with reference to FIG. The ballast water treatment device 2 according to the second embodiment basically has the same configuration as the ballast water treatment device 1 according to the first embodiment, and has the same effect. However, the second embodiment is different from the first embodiment in that the water stored in the spare tank 36 is used as the inboard water instead of the domestic water stored in the boat.

[Ballast water treatment equipment]
The ballast water treatment apparatus 2 includes a pipe 11, a ballast pump 10, a filter 20, a dissolving unit 30, an injecting unit 40, a concentration measuring unit 90, a mixer 50, and a temperature measuring device, as in the first embodiment. It mainly includes a unit 70 and a flow control unit 80. Here, in the second embodiment, the dissolving means 30 has first and second preliminary pipes 34 and 35, a preliminary tank 36, and a chemical container 31. Further, a first switching valve 91 for switching between the flow of water and the shutoff of water in the pipe is provided downstream of the portion P2 of the pipe 11 to which the first preliminary pipe 34 is connected.

  The first spare pipe 34 has one end connected to a portion P <b> 2 of the pipe 11 on the downstream side of the filter 20, and the other end connected to a spare tank 36. The first spare pipe 34 is provided with a second switching valve 92 for switching between water flow and cutoff in the pipe. The second auxiliary pipe 35 has one end connected to the chemical container 31 and the other end connected to the auxiliary tank 36.

  The spare tank 36 is a tank for storing seawater pumped into the ship before filling the ballast tank 60. Foreign matter is removed from the preliminary tank 36 by being filtered by the filter 20, and the seawater that has passed through the first preliminary pipe 34 is stored.

  In the second embodiment, unlike in the first embodiment, the seawater (tank stored water) stored in the spare tank 36 in the ship before filling the ballast tank 60 is used as the inboard water. The seawater passes through the pipe 11 and the first auxiliary pipe 34 and is stored in the auxiliary tank 36, so that the water temperature is stable and the water quality is improved. A temperature measuring unit 70 is attached to the auxiliary tank 36, and the temperature of the seawater in the auxiliary tank 36 is measured.

  The injection means 40 includes a supply pipe 41 and a liquid sending pump 42. The supply pipe 41 has one end connected to the chemical container 31 and the other end connected to a part P3 downstream of the part P2 and upstream of the mixer 50 in the pipe 11.

[Ballast water treatment method]
Next, a ballast water treatment method using the ballast water treatment device 2 will be described.

  First, before the filling of the ballast tank 60 is started, the seawater is stored in the spare tank 36. At this time, the first switching valve 91 is closed, and the second switching valve 92 is opened. The opening and closing of the first and second switching valves 91 and 92 may be performed by a control unit (not shown) or may be performed manually. The seawater pumped into the pipe 11 by the ballast pump 10 is filtered by the filter 20, flows into the first preliminary pipe 34 via the site P <b> 2, and is then stored in the preliminary tank 36. The seawater is stored in the reserve tank 36 so that the water temperature falls within a certain range. The water storage in the spare tank 36 may be performed at any time before the filling of the ballast tank 60 is started and the operation of the vessel is not affected.

  Then, the filling of the ballast tank 60 is started. At this time, the first switching valve 91 is opened and the second switching valve 92 is closed, and the ballast water is pumped into the pipe 11. The seawater stored in the reserve tank 36 flows into the chemical container 31 via the second reserve pipe 35. Then, the disinfectant 3 is dissolved in the seawater to obtain the disinfectant solution S. The disinfectant solution S is guided to the pipe 11 via the supply pipe 41 and injected into ballast water, and the ballast water is sterilized. Thereafter, the mixture is stirred by the mixer 50 to make the chlorine concentration uniform, and then the ballast water is stored in the ballast tank 60.

  In the second embodiment, a spare tank 36 for storing seawater pumped into the ship before filling the ballast tank 60 is provided, and the seawater stored in the spare tank 36 is used as shipboard water. The seawater has a stable water temperature by being stored in the auxiliary tank 36, and the quality of water such as turbidity has also been improved due to sedimentation of sediments. Therefore, by using the seawater stored in the spare tank 36 as the inboard water, it is possible to more effectively suppress the variation in the dissolution behavior of the germicide 3. In addition, by storing the seawater filtered by the filter 20 in the preliminary tank 36, the turbidity can be reduced and the water quality can be further improved, so that the dissolution behavior of the germicide 3 can be further stabilized. it can.

(Modification)
Lastly, a modification of the first and second embodiments will be described.

  As in the first and second embodiments, the dissolving means 30 is limited to a mode in which the disinfectant 3 is dissolved and the disinfectant solution S is prepared by flowing inboard water into the chemical container 31 filled with the disinfectant 3. Instead, the disinfectant solution S may be prepared by charging and dissolving the disinfectant 3 into the inboard tank 33 or the spare tank 36. Further, the inboard water may be any water stored in the ship, and is not limited to water stored as domestic water in the ship or water stored in the spare tank 36. The disinfectant 3 is not limited to a solid one, but may be a liquid one.

  The disinfectant 3 is not limited to the case where the disinfectant 3 is filled in the chemical container 31 as in the first and second embodiments, and the disinfectant 3 may be directly disposed in the pipe. In this case, in order to prevent the disinfectant 3 from flowing downstream due to the flow of water, a mesh or screen-shaped member for blocking the disinfectant 3 may be arranged in the pipe.

  In the first and second embodiments, a plurality of medicine containers 31 are prepared, and they may be arranged in series and used simultaneously, or may be arranged in parallel and used alternately. In this case, the disinfectant 3 can be replenished when the remaining amount of the disinfectant 3 in one chemical container 31 becomes low, and another chemical container 31 can be used during the replenishment operation.

  In the second embodiment, the water stored in the reserve tank 36 is not limited to seawater, but may be brackish water, freshwater, lake water, or river water.

  In the first and second embodiments, the filter 20 may be omitted.

  In the first and second embodiments, the concentration measuring section 90 and the temperature measuring section 70 may be omitted.

(Example 1)
In Example 1, a prototype treatment apparatus simulating the ballast water treatment apparatus 1 shown in FIG. 1 was used. As the disinfectant 3, granules of trichloroisocyanuric acid (average diameter: 2 mm, weight: 10 g) are used, filled in a polypropylene (PP) mesh bag having an opening of 0.1 mm, and filled in the chemical container 31. I attached it. Dewatered water was passed through this. The water temperature was 18 ° C. When the TRO concentration in the solution was measured with a chlorine meter while changing the flow rate of water, the TRO concentration was 420 mg / L when the flow rate was 2 L / min.

  A granule of trichloroisocyanuric acid (average diameter: 2 mm, weight: 10 g) is further prepared, filled in a mesh bag made of PP having an opening of 0.1 mm, and attached to the chemical container 31 to obtain a disinfectant. 3 was replaced. A bactericide solution S was prepared by passing dechlorinated water at a temperature of 18 ° C. at a flow rate of 2 L / min.

  1000 L of natural seawater was used as raw water, flowed into the pipe 11 at a flow rate of 16.7 L / min (1000 L / h), and the disinfectant solution S was injected into the pipe 11 by the liquid feed pump 42. After stirring by the mixer 50, the TRO concentration of the ballast water was measured by the concentration measuring unit 90. When the target value of the TRO concentration was set to 5.0 ± 0.2 mg / L, the measured value was 5.0 mg / L, which was within the range of the target value.

  Thereafter, the TRO concentration is measured at intervals of 5 minutes, and the measurement result is fed back to the flow rate control unit 80, and the operation is performed for one hour while controlling the operation of the liquid feed pump 42 so as to match the target value of 5.0 mg / L. Continued. As a result, as shown in Table 1, the TRO concentration changed within a range of 5.0 ± 0.2 mg / L (Table 1).

(Example 2)
In Example 2, a prototype treatment apparatus simulating the ballast water treatment apparatus 2 shown in FIG. 2 was used. Two tablets of trichloroisocyanuric acid (cylindrical shape of 30 mmφ, 15 g) as the disinfectant 3 were filled in a PP mesh bag having an opening of 0.1 mm and attached to the chemical container 31.

  First, natural seawater (100 L) was introduced into the preliminary tank 36 via the first preliminary pipe 34 and stored in a room at 24 ° C. for 24 hours (operation 1). At this time, the seawater temperature was 22 ° C.

  Next, the seawater in the preliminary tank 36 was sent to the chemical container 31 at a flow rate of 2 L / min (operation 2). By this operation, the disinfectant 3 in the chemical container 31 was dissolved in seawater to prepare a disinfectant solution S. Simultaneously with the above operation 2, 1000 L of natural seawater as raw water was introduced into the pipe 11 at a flow rate of 16.7 L / min (1000 L / h), and the disinfectant solution S was injected into the pipe 11 by the liquid feed pump 42 (operation 3). After stirring by the mixer 50, the TRO concentration of the ballast water was measured by the concentration measuring unit 90. When the target value of the TRO concentration was set to 5.0 ± 0.2 mg / L as in Example 1 above, the measured value was 4.8 mg / L, which was within the target value range.

  Thereafter, the TRO concentration is measured at intervals of 5 minutes, and the measurement result is fed back to the flow rate control unit 80, and the operation is performed for one hour while controlling the operation of the liquid feed pump 42 so as to match the target value of 5.0 mg / L. Continued. As a result, as shown in Table 1, the TRO concentration changed within a range of 5.0 ± 0.2 mg / L (Table 1).

(Comparative example)
Except that the preliminary tank 36 was removed from the ballast water treatment apparatus 2 shown in FIG. 2 and the raw water flowing from the pipe 11 into the first and second preliminary pipes 34 and 35 was directly passed through the chemical container 31. A test was performed in the same manner as in Example 2. The test was performed in winter as in Examples 1 and 2. The target value of the TRO concentration of the ballast water was 5.0 ± 0.2 mg / L.

  Specifically, the natural seawater was directly sent to the chemical container 31 through the first and second preliminary pipes 34 and 35 without previously storing the natural seawater. By this operation, the disinfectant 3 in the chemical container 31 was dissolved in seawater to prepare a disinfectant solution S. Simultaneously with this liquid feeding operation, 1000 L of natural seawater is flowed into the pipe 11 at a flow rate of 16.7 L / min (1000 L / h) as raw water (temperature 4 ° C.), and the disinfectant solution S is fed into the pipe 11 by the liquid feed pump 42. Was injected. After stirring by the mixer 50, the TRO concentration of the ballast water was measured by the concentration measuring unit 90. When the injection flow rate of the disinfectant solution S was started at 2 L / min, the initially measured TRO concentration was 0.8 mg / L.

  The measured value of the TRO concentration was fed back to the flow control unit 80, and the operation was continued for one hour while controlling the operation of the liquid feed pump 42 to adjust the TRO concentration to 5 mg / L. At this time, the operation of the liquid sending pump 42 was controlled so that the injection flow rate (liquid sending amount) of the disinfectant solution S increased up to 15 L / min (corresponding to the TRO concentration of 5.9 mg / L in Table 1).

  When the TRO concentration was measured every 5 minutes, the TRO concentration did not reach 5 mg / L for the first 15 minutes, exceeded 5 mg / L thereafter, and the TRO concentration was not stabilized for the first 30 minutes or more, and the target value was not reached. It did not fall within the range (Table 1).

  In the case where the TRO concentration is not stable as in the comparative example, if the chlorine concentration is low, the bactericidal activity is reduced, and the standard defined in the Ballast Management Convention cannot be achieved. On the other hand, if the flow rate of ballast water is reduced to increase the chlorine concentration, the time required for filling will increase, and the berthing time of the ship will increase, leading to a loss in logistics. In contrast, in the first and second embodiments, instead of seawater immediately after being taken into the ship, water stored in the ship and having a water temperature within a certain range is used as the dissolving solution for the disinfectant 3. , The TRO concentration of the ballast water could be easily controlled to the target range.

  The following is a brief description of the above embodiment.

  The ballast water treatment apparatus according to the present embodiment has a dissolving means for dissolving a disinfectant in shipboard water stored in a ship, and a disinfectant solution obtained by the dissolving means, and a pipe for guiding ballast water to a ballast tank. And an injecting means for injecting the water into the air.

  In the above ballast water treatment apparatus, ballast water can be sterilized by injecting a disinfectant solution in which a disinfectant is dissolved in shipboard water stored in the ship into a pipe. Since the inboard water is stored on board, the water temperature is within a certain range. For this reason, the variation in dissolution behavior of the disinfectant can be suppressed as compared with the conventional case where raw water having an unstable water temperature immediately after being taken into the ship is used as the dissolution liquid as it is. Therefore, according to the ballast water treatment device, the chemical concentration of the ballast water can be easily controlled to a desired range.

  In the above ballast water treatment apparatus, it is preferable that the inboard water is water stored as domestic water in the ship.

  By using the water stored in the ship as domestic water and having stable water temperature and water quality as the above-mentioned water in the ship, fluctuations in the dissolution behavior of the disinfectant can be suppressed more effectively. Living water stored in a dedicated tank on the ship may be used directly as a solvent for the disinfectant, or some of the water transferred from the dedicated tank to another tank may be used as a solvent for the disinfectant. You may.

  In the above ballast water treatment apparatus, it is preferable that the dissolving means include a spare tank for storing water pumped into the ship before filling the ballast tank. Preferably, the inboard water is water stored in the spare tank.

  The water stored in the spare tank has a stable water temperature, and the sedimentation of the sediment has improved the water quality such as turbidity. For this reason, by using the water stored in the spare tank as the inboard water, it is possible to more effectively suppress the variation in the dissolution behavior of the germicide.

  It is preferable that the ballast water treatment device further includes a filtering member for filtering water stored in the spare tank.

  Since the water after filtration has a low turbidity and an improved water quality, it is suitable as a solvent for stably dissolving the disinfectant.

  The ballast water treatment device may further include a concentration measuring unit that measures a chemical concentration of the ballast water into which the disinfectant solution is injected, and the disinfectant solution injected by the injecting unit based on a measurement result by the concentration measuring unit. And a flow control unit that adjusts the flow rate.

  According to the above configuration, the drug concentration of the ballast water after the sterilization treatment is measured, and the measurement result is fed back to the injection flow rate of the sterilant solution, so that the drug concentration of the ballast water can be adjusted to an appropriate value. Thereby, while maintaining the sterilizing effect, it is possible to suppress corrosion of pipes and tanks caused by an excessive drug concentration.

  The ballast water treatment device may further include a temperature measurement unit configured to measure a temperature of the shipboard water, and a flow control unit configured to adjust a flow rate of the disinfectant solution injected by the injection unit based on a measurement result obtained by the temperature measurement unit. It is preferable to provide:

  The dissolution behavior of the above bactericide changes depending on the water temperature. For this reason, the temperature of the water in the ship is measured by the temperature measurement unit, and the measurement result is fed back to the injection flow rate of the disinfectant solution, so that the drug concentration of the ballast water can be adjusted to an appropriate value.

  In the ballast water treatment device, it is preferable that the bactericide is trichloroisocyanuric acid.

  Since trichloroisocyanuric acid has relatively low solubility in water, it can maintain a bactericidal effect for a long period of time. Further, it can be stably maintained at a high temperature. Further, unlike calcium hypochlorite, etc., the generation of precipitates when dissolved in water can also be suppressed. Therefore, trichloroisocyanuric acid can be suitably used as a bactericide.

  Further, in the ballast water treatment device, it is preferable that the bactericide is dichloroisocyanurate.

  Since dichloroisocyanurate has high solubility in water, a disinfectant solution can be prepared in a short time. Further, it can be stably maintained at a high temperature. Further, unlike calcium hypochlorite, etc., the generation of precipitates when dissolved in water can also be suppressed. Therefore, dichloroisocyanurate can be suitably used as a bactericide.

  The ballast water treatment method according to the present embodiment is a method for guiding sterilized ballast water to a ballast tank. In this ballast water treatment method, a disinfectant solution is prepared by dissolving a disinfectant in shipboard water stored in a ship, and the disinfectant treatment is performed by injecting the disinfectant solution into ballast water guided to the ballast tank. .

  In the above ballast water treatment method, sterilization treatment can be performed by injecting a bactericide solution obtained by dissolving a bactericide in shipboard water stored in a ship into ballast water. Since the inboard water is stored on board, the water temperature is within a certain range. For this reason, it is possible to suppress a change in dissolution behavior of the germicide as compared with a case where raw water having an unstable water temperature is used as a dissolving solution as in the related art. Therefore, according to the ballast water treatment method, the chemical concentration of the ballast water can be easily controlled to a desired range.

  In the above ballast water treatment method, it is preferable that the inboard water is water stored as domestic water in the ship.

  By using the water stored in the ship as domestic water and having stable water temperature and water quality as the above-mentioned water in the ship, fluctuations in the dissolution behavior of the disinfectant can be suppressed more effectively.

  In the above ballast water treatment method, it is preferable that the inboard water is tank storage water stored in a spare tank onboard before filling the ballast tank.

  The water stored in the tank has a stable water temperature by being stored in the spare tank, and the quality of the water is also improved due to sedimentation of sediments. For this reason, by using the tank stored water as the inboard water, it is possible to more effectively suppress the variation in the dissolution behavior of the germicide.

  In the above ballast water treatment method, it is preferable that the tank stored water is filtered and stored in the spare tank.

  The dissolution behavior of the disinfectant can be further stabilized by using the tank stored water whose water quality has been improved by the filtration as the inboard water.

  In the ballast water treatment method, it is preferable to measure a drug concentration of the ballast water into which the germicide solution has been injected, and to adjust an injection flow rate of the germicide solution based on the measurement result.

  According to the above method, the measurement result of the drug concentration of the ballast water after the sterilization treatment is fed back to the injection flow rate of the disinfectant solution, whereby the drug concentration of the ballast water can be adjusted to an appropriate value.

  In the ballast water treatment method, it is preferable that a temperature of the inboard water is measured, and an injection flow rate of the disinfectant solution is adjusted based on the measurement result.

  According to the above method, the result of the temperature measurement of the shipboard water is fed back to the injection flow rate of the disinfectant solution in consideration of the variation in dissolution behavior of the disinfectant due to the water temperature, thereby adjusting the drug concentration of the ballast water to an appropriate value. be able to.

  In the above ballast water treatment method, the bactericide is preferably trichloroisocyanuric acid.

  Since trichloroisocyanuric acid has relatively low solubility in water, it can maintain a bactericidal effect for a long period of time. Further, it can be stably maintained at a high temperature. Further, unlike calcium hypochlorite, etc., the generation of precipitates when dissolved in water can also be suppressed. Therefore, in the above method, trichloroisocyanuric acid can be suitably used as a bactericide.

  Further, in the ballast water treatment method, it is preferable that the bactericide is dichloroisocyanurate.

  Since dichloroisocyanurate has high solubility in water, a disinfectant solution can be prepared in a short time. Further, it can be stably maintained at a high temperature. Further, unlike calcium hypochlorite, etc., the generation of precipitates when dissolved in water can also be suppressed. Therefore, in the above method, dichloroisocyanurate can be suitably used as a bactericide.

Claims (11)

Dissolving means for dissolving the disinfectant in the shipboard water stored in the ship,
Injecting means for injecting the disinfectant solution obtained by the dissolving means into a pipe for guiding ballast water to a ballast tank ,
The dissolving means includes a spare tank for storing water pumped into the ship before filling the ballast tank,
The ballast water treatment device, wherein the inboard water is water stored in the spare tank . The dissolving means includes a chemical container filled with the germicide, a first auxiliary pipe connecting the pipe and the auxiliary tank, and a second auxiliary pipe connecting the auxiliary tank and the chemical container. In addition,
Switching means for switching between inflow and stoppage of ballast water from the pipe to the first preliminary pipe;
The switching means is controlled so that ballast water flows from the pipe to the first spare pipe before filling the ballast tank, and ballast from the pipe to the first spare pipe at the time of filling the ballast tank. The ballast water treatment device according to claim 1, further comprising: a control unit configured to control the switching unit so as to stop inflow of water. Wherein the water is stored in the auxiliary tank further comprising a filtering member for filtering the ballast water treatment system according to claim 1. A concentration measurement unit that measures the drug concentration of the ballast water into which the germicide solution has been injected,
The ballast according to any one of claims 1 to 3 , further comprising: a flow control unit configured to adjust a flow rate of the germicide solution injected by the injection unit based on a measurement result by the concentration measurement unit. Water treatment equipment. A temperature measuring unit that measures the temperature of the inboard water,
The ballast according to any one of claims 1 to 3 , further comprising: a flow control unit configured to adjust a flow rate of the disinfectant solution injected by the injection unit based on a measurement result by the temperature measurement unit. Water treatment equipment. The ballast water treatment device according to any one of claims 1 to 5 , wherein the disinfectant is trichloroisocyanuric acid. A ballast water treatment method for guiding sterilized ballast water to a ballast tank,
Before filling the ballast tank, store ballast water in a spare tank onboard as tank storage water;
At the time of filling the ballast tank, a disinfectant solution is prepared by dissolving a disinfectant in the tank storage water , and disinfecting treatment is performed by injecting the disinfectant solution into ballast water guided to the ballast tank. And a ballast water treatment method. The ballast water treatment method according to claim 7 , wherein the tank stored water is stored in the spare tank after being filtered. The ballast water treatment method according to claim 7 , wherein a drug concentration of the ballast water into which the disinfectant solution is injected is measured, and an injection flow rate of the disinfectant solution is adjusted based on the measurement result. 9. The ballast water treatment method according to claim 7 , wherein a temperature of the inboard water is measured, and an injection flow rate of the disinfectant solution is adjusted based on the measurement result. The method for treating ballast water according to any one of claims 7 to 10 , wherein the disinfectant is trichloroisocyanuric acid.

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