JP2008110276A - Heat recovery type purification treatment method of ballast water and heat recovery type purification treatment system using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ballast water purification treatment system by a thermal treatment method. <P>SOLUTION: A heat recovery type purification treatment system 1 comprises a plate-type heat exchange device 3 for exchanging heat between high-temperature ballast water after purification treatment is carried out by the thermal treatment method and low-temperature ballast water drawn up from a water-intake port 21, a high-temperature maintaining device 5 for maintaining the temperature of the high-temperature ballast water obtained by heating the low-temperature ballast water as much as extinction time of plankton and sterilization with the plate-type heat exchange device 3, a water-intake line 2 for connecting the water-intake port 21 and the plate-type heat exchange device 3, a water-inlet line 4 and a water-outlet line 6 for connecting the plate-type heat exchange device 3 and the high-temperature maintaining device 5, and a water-filling line 7 for connecting the plate-type heat exchange device 3 and the water-filling port 81 of a ballast tank 8. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat recovery type purification process method for purifying ballast water by a heat treatment method and a heat recovery type purification process system using the same.

In order to eliminate the adverse effects of plankton and bacteria in the drained ballast water on the surrounding sea area, ships with a ballast tank of less than 5000 m ³ based on the Ballast Water Management Convention adopted by the IMO (International Maritime Organization) in 2004 All ships, including those built after 2009, and existing ships are required to be equipped with a ballast water purification system from 2017 onwards. Currently, an offshore exchange system that exchanges ballast water while the ship is sailing is also used separately from the purification treatment system. This offshore exchange system is prohibited by the above-mentioned Ballast Water Management Convention. Development of a practical purification system that can be mounted on ships is being promoted according to the schedule of

  Various treatment methods have been proposed as specific purification methods for ballast water. Specifically, a filtration treatment method for filtering ballast water, an electrical treatment method for energizing the ballast water, an ultraviolet treatment method for irradiating the ballast water with ultraviolet rays, a chemical treatment method for administering a drug to the ballast water, and a ballast water It can be roughly divided into heat treatment methods. Each processing method is used independently, and a processing method in which several types are combined or other cavitations are added and combined has been proposed (Patent Document 3). Ballast water purification treatment is usually performed at the stage of pumping up ballast water before departure and pouring it into the ballast tank.In addition, ballast water is circulated during navigation, and after landing, Is performed on the ballast water when draining from the ballast tank.

  Although the filtration method is suitable for removing plankton, it is difficult to remove bacteria, so it is used as a supplementary pre-treatment or post-treatment for other treatment methods. The electrical treatment method and the ultraviolet ray treatment method are low in plankton killing effect and bacteria sterilization effect, and are difficult to purify a large amount of ballast water, so that there is no prospect for practical use. The chemical treatment method has demonstrated the killing effect of plankton and the bactericidal effect of bacteria, and can purify a large amount of ballast water, but there is a problem of water contamination due to the administered drug. On the other hand, in the heat treatment method, if the ballast water can be heated to a temperature sufficient to kill plankton and bacteria, the plankton killing effect and bacteria sterilization effect are recognized, and there is no problem of water pollution seen in the chemical treatment method. Since there is an advantage, it is considered to be a preferable processing method.

  Patent Document 1 proposes a method of purifying ballast water poured into a ballast tank by a heat treatment method. Specifically, the ballast tank is heated by warm water or steam as a heat medium to indirectly heat the ballast water, or the heat medium is supplied to the ballast water to directly heat the ballast water. The hot water or steam as the heating medium uses hot water or steam obtained by heat exchange with engine cooling water, but the specific configuration of the heat exchange device is unknown. Since the engine cooling water is 46 ° C. to 50 ° C., the ballast water can be heated up to 50 ° C., but if necessary, it can be heated to 60 ° C. or higher using a heater. Plankton and bacteria are said to be killed by heating at 45 ° C for 3 minutes.

  Patent Document 2 proposes a method of purifying ballast water that has been pumped up and poured into a ballast tank, or ballast water that has been poured into a ballast tank by a heat treatment method. Specifically, heat exchange is performed between high-temperature exhaust gas discharged from the engine or high-temperature cooling water that has cooled the exhaust gas and ballast water, and is substantially the same as Patent Document 1. The specific configuration of the heat exchange device is unknown. The heating temperature of the ballast water is the same as in Patent Document 1, and it is stated that plankton and bacteria are killed by heating the ballast water for 40 minutes or more and 8 minutes, preferably 45 degrees C or more for 3 minutes.

  Patent Document 3 proposes a method of purifying ballast water poured into a ballast tank by a heat treatment method. Specifically, heat exchange is performed between the high-temperature exhaust gas discharged from the engine (waste heat source) and the ballast water, which is almost the same as in Patent Document 2. Although there is no explicit description of the heating temperature of the ballast water, it is considered that the heating is equivalent to Patent Document 1 and Patent Document 2. Moreover, although it is said that it heats further using the heat exchanger for preheating as needed, the structure of the specific heat exchanger and the heat exchanger for preheating is unknown. In addition, the purification method of Patent Document 3 uses cavitation with air mixed with ballast water, and physically destroys and kills plankton (pests) that could not be killed by heating. Yes.

JP 08-091288 A ([Claim 1] to [Claim 5], [0028], [0038], [0047], [0055]) JP 2003-181443 A ([Claim 1] to [Claim 3], [0008], [0017], [0018], [0025], [0027], [0031]) JP 2004-284481 A ([Claim 1] to [Claim 3], [0030] to [0032])

  Patent Documents 1 and 2 state that plankton and bacteria can be killed by heating ballast water at 40 ° C. or more for 8 minutes or 45 ° C. or more for 3 minutes. However, as understood from the relationship between the heating temperature and the heating time in the heat sterilization treatment in other technical fields, even if the plankton can be killed at the temperature, it is doubtful that the bacteria can be killed. . This can also be inferred from the fact that Patent Document 3 clearly indicates the combined use of cavitation in addition to the heat treatment method.

In the Ballast Water Management Convention, the number of organisms with a minimum size of 50 μm or more (mainly zooplankton) is less than 10 / m ^{3 in} the ballast water after purification treatment, and the number of organisms with a minimum size of 10 μm or more but less than 50 μm (mainly phytoplankton) is 10 / Requires less than mL, virulent cholera (O1 and O139) less than 1 cfu / 100 mL, E. coli less than 250 cfu / 100 mL, and enterococci less than 100 cfu / 100 mL. Here, since the pathogenic cholera cannot be killed sufficiently if it is not heated for several minutes at 70 ° C or higher, and the optimal temperature for growth is 37 ° C, the ballast water of about 40 ° C is used instead. There is a risk of breeding. From this, it is considered that when ballast water is purified by a heat treatment method, the ballast water must be heated to at least 70 ° C. or more, preferably about 80 ° C. (basic problem).

  However, in each of the purification treatment methods of Patent Documents 1 to 3, since the ballast water is heated by directly or indirectly using the exhaust gas of the engine, the ballast water can be heated only to 50 ° C. at most. In order to heat more than that, a separate auxiliary heating device (a heater in Patent Document 1 or a heat exchanger for preheating in Patent Document 3) must be used. If the ballast water heated to 50 ° C. by the exhaust gas of the engine is further heated to 80 ° C., the auxiliary heating device needs to supply an amount of heat sufficient to raise the ballast water by 30 ° C. In addition, the supply of the heat amount must be maintained during the purification process of the ballast water, and it is difficult to provide a practical auxiliary heating device that can be mounted on a ship in view of the purification process of a large amount of ballast water. From this, it is possible to sufficiently heat the ballast water without depending on the auxiliary heating device, to reduce the capacity required for the required auxiliary heating device, and to derive a problem of downsizing the auxiliary heating device (prerequisite issue).

  In addition, for example, Patent Document 1 proposes a purification method in which ballast water is heated while being poured into a ballast tank. This means that hot water of 40 ° C. or higher is stored in the ballast tank. If the temperature is at the above level, the amount of heat from the ballast water will not cause damage to the ballast tank, but the ballast tank that stores the ballast water at 40 ° C or higher will receive a continuous heat load and the structural materials and paint will deteriorate. There is a problem that it becomes easy and the durability is greatly reduced. That is, in the purification method for ballast water by the heat treatment method, it is necessary to heat the ballast water during the purification treatment, but it is desired to cool the ballast water to room temperature after the purification treatment (accompanying problem). Therefore, the ballast water can be heated without relying solely on the auxiliary heating device, and if possible, the ballast water can be heated to a temperature at which bacteria can be sufficiently killed. In order to develop a purification method and a purification system using a heat treatment method that can be used.

  What has been developed as a result of the study is a method for purifying ballast water by heating the ballast water to kill the plankton and bacteria in the ballast water, from the high-temperature ballast water and the intake after being purified by the heat treatment method. Heat exchange with the pumped low-temperature ballast water, and the low-temperature ballast water pumped from the intake is heated by the heat recovered from the high-temperature ballast water after being purified by the heat treatment method and before being purified by the heat treatment method The high-temperature ballast water after the purification treatment by the heat treatment method is cooled by recovering heat, and the low-temperature ballast water to be sent to the ballast tank is cooled. Abbreviated as “purification treatment method”).

  The purification treatment method is described as a case where the ballast water is purified in the process (in-line) of pumping from the intake port and pouring into the ballast tank. However, the purification method of the present invention is a process for purifying ballast water in the process of transferring ballast water between the ballast tanks during navigation (in-tank), or a process of draining ballast water from the ballast tank through the water intake ( When the ballast water is purified in the out tank), it can be used in substantially the same manner as when the ballast water is purified in the process of being pumped from the intake port and poured into the ballast tank. For example, when purifying ballast water in the process of transferring ballast water between the ballast tanks during navigation, the `` low temperature ballast water pumped from the intake port '' in the above description is `` low temperature ballast water pumped from the ballast tank '' Replace it. In addition, when purifying ballast water in the process of draining ballast water from the ballast tank through the water intake, the “low temperature ballast water pumped from the water intake” in the above description is “low temperature ballast water discharged from the ballast tank”, “Low-temperature ballast water sent to the ballast tank” is read as “low-temperature ballast water drained into the sea”. The following describes the case where the ballast water is purified during the process of pumping from the intake port and pouring into the ballast tank (described above), but the ballast water is purified during the process of transferring the ballast water between the ballast tanks during navigation. The case or the case where the ballast water is purified in the process of draining the ballast water from the ballast tank through the water intake port will be described in the same manner as described above.

  In the purification treatment method of the present invention, the heat recovered from the high-temperature ballast water that has been subjected to the purification treatment by the heat treatment method is applied to the low-temperature ballast water pumped from the water intake and heated. As a result, even if the low-temperature ballast water is heated by the auxiliary heating device, the amount of heat required for the auxiliary heating device can be suppressed (solution of the precondition), in addition to the conventionally known engine exhaust gas and steam of the auxiliary boiler, And the like as an auxiliary heating device, it becomes easy to heat ballast water to a high temperature (for example, 80 ° C.) (solution of basic problems). In addition, the high-temperature ballast water from which heat has been recovered is naturally cooled to become low-temperature ballast water, and can be stored without applying a thermal load to the ballast tank (solution of incidental problems). Thus, the purification treatment method of the present invention provides a realistic purification treatment method using a heat treatment method by efficiently utilizing heat.

  In the present invention, it is preferable to use a heat exchange device having as high a heat exchange efficiency as possible from the viewpoint of using heat without waste. From this, a plate-type heat exchange device is suitable for heat exchange between the high-temperature ballast water that has been purified by the heat treatment method and the low-temperature ballast water pumped from the water intake. The plate-type heat exchanging device alternately uses low-temperature ballast water and high-temperature ballast water as counterflows (flows in which the flow directions oppose each other) with respect to the flow path between the plates that are arranged between a plurality of plates (heat transfer surfaces). In the heat exchange device that exchanges heat through the plate, the counter flow exchanges heat across a plate having a large area that contributes to heat exchange, so that high heat exchange efficiency is achieved. This plate type heat exchange device can achieve a heat exchange efficiency close to 100% if an ideal device configuration is adopted (for example, if heat exchange units are configured in multiple stages as will be described later). Can be heated to a temperature approximately equal to the temperature of the hot ballast water. For example, even if the low temperature ballast water is 20 ° C., if the high temperature ballast water is 80 ° C., the low temperature ballast water can be heated to about 78 ° C. In other words, the high temperature ballast water can be cooled to the temperature of the low temperature ballast water, that is, about 22 ° C.

  The present invention does not heat the low-temperature ballast water only by heat exchange, and as described above, the heat exchange device cannot achieve 100% heat exchange efficiency, and the heat loss of the purification system itself described later is considered. Therefore, such a shortage of heat must be compensated by an auxiliary heating device. However, from the viewpoint of using heat without waste through heat exchange and minimizing the amount of heat required for the auxiliary heating device, the low-temperature ballast water pumped up from the intake port is taken from the high-temperature ballast water that has been purified by the heat treatment method. It is heated as much as possible by the recovered heat and purified by a heat treatment method that is supplementarily heated by an auxiliary heating device. The auxiliary heating device can use various conventionally known heat sources, such as engine exhaust gas, auxiliary boiler steam, and electric heat. In the present invention, since the low-temperature ballast water is sufficiently heated by heat exchange, the amount of heat required for the auxiliary heating device may be small. For example, the auxiliary boiler can be reduced in size.

  The above purification treatment method is a purification system for ballast water that heats the ballast water and kills plankton and bacteria in the ballast water, and is pumped from the high temperature ballast water and the intake after the purification treatment by the heat treatment method. Plate-type heat exchange device for exchanging heat with low-temperature ballast water, and a high-temperature maintenance device for maintaining the temperature of the high-temperature ballast water obtained by heating the low-temperature ballast water by the plate-type heat exchange device only during the death time of plankton and sterilization A water intake line connecting the water intake and the low temperature path inlet of the plate heat exchanger, a water intake line connecting the low temperature path outlet of the plate heat exchanger and the water inlet of the high temperature maintaining apparatus, and maintaining the high temperature A water discharge line connecting a water outlet of the apparatus and a high temperature path inlet of the plate heat exchanger, and a height of the plate heat exchanger Heat recovery type water treating system composed ballast water and a water injection line connecting the water inlet path exit and ballast tank (hereinafter, abbreviated as "purification processing system") embodied by.

  The plate-type heat exchange device is a heat exchange device with good heat exchange efficiency as described above. However, since the amount of ballast water to be heated is large, the temperature that can be achieved by heating can be increased by increasing each plate (heat transfer surface) and increasing the number of the plates. Heating around 10 ° C per exchanger is a practical limit. Thus, the plate heat exchanger used in the present invention is composed of a plurality of heat exchanger units each having a low temperature path inlet, a low temperature path outlet, a high temperature path inlet, and a high temperature path outlet, and the low temperature of the heat exchanger unit in the preceding stage. The path outlet may be connected to the low temperature path inlet of the rear heat exchange unit, and the high temperature path outlet of the rear heat exchange unit may be connected to the high temperature path inlet of the front heat exchange unit. A plate-type heat exchanger composed of a plurality of heat exchange units each heat exchange unit heats the low temperature ballast water step by step at a predetermined temperature, cools the high temperature ballast water, and finally cools the low temperature ballast water. Is heated to the temperature equivalent to the temperature of the high temperature ballast water, and the high temperature ballast water is cooled to the temperature equivalent to the temperature of the low temperature ballast water. For example, when the low temperature ballast water is 20 ° C. and the high temperature ballast water is 80 ° C. and heating can be performed at less than 10 ° C. for each heat exchange unit, the heat exchange unit is connected in six stages and the low temperature ballast water and the high temperature ballast water are By exchanging heat, low temperature ballast water can be heated to about 78 ° C, and high temperature ballast water can be cooled to about 22 ° C.

  The high temperature maintaining device maintains the temperature of the high temperature ballast water obtained by heating the low temperature ballast water for a predetermined time, and kills plankton and bacteria. Here, as described above, 100% heat exchange efficiency cannot be achieved even by heat exchange by the plate heat exchange device, and heat loss actually occurs. Therefore, it is necessary to compensate for insufficient heat. Therefore, an auxiliary heating device is provided between the water inlet and the water outlet to further heat the high temperature ballast water sent from the plate heat exchange device through the water inlet line and convert it to high temperature ballast water before being purified by the heat treatment method. It was. Here, when the high temperature maintaining device is a stationary tank having a water inlet and a water outlet, the steam line for blowing the steam into the high temperature ballast water in which the exhaust gas of the engine or the steam of the auxiliary boiler is stopped Submerge in high-temperature ballast water stored in a storage tank. Moreover, when a high temperature maintenance apparatus is a stopping pipeline which connects a water inlet and a water outlet, it is good to wind a heating wire (covered heating wire) around the said stopping pipeline.

  When heat is exchanged in a plate heat exchanger, if foreign matter is mixed in the low-temperature ballast water or high-temperature ballast water, the foreign matter gets caught in the narrow inter-plate flow path, and the flow of the low-temperature ballast water or high-temperature ballast water deteriorates. As a result, the heat exchange efficiency may be reduced, or the worst plate heat exchange device may be damaged. Therefore, the water intake line in the purification treatment system of the present invention is preferably provided with a filtration device between the water inlet and the low temperature path inlet of the plate heat exchange device. The filtration device has a function of removing relatively large plankton in addition to removing the foreign matter. Conventionally known various filtering devices can be used as this filtering device, but it is difficult to sufficiently remove foreign matters and plankton with one type of filtering device. Therefore, the filtration device may be configured separately into a coarse filtration device and a fine filtration device. The coarse filtration device is preferably a normal filter filtration device or a centrifugal filtration device, and the microfiltration device is preferably an anthracite filtration device.

  Since the plankton has already been killed by the purification treatment in the high-temperature ballast water flowing into the plate heat exchanger, the plankton may be removed in advance by a filter, but the plankton contained in the low-temperature ballast water is Since it is heated through the exchange device and needs to be killed by the purification process, it cannot be removed by a filter in advance. Plankton is likely to adhere to the surroundings when the low-temperature ballast water is less than 40 ° C, but it is considered that the plankton peels off from the surroundings when the low-temperature ballast water exceeds 40 ° C. For this reason, plankton tends to adhere to the plate (heat transfer surface) of the plate heat exchanger until the low-temperature ballast water is heated to 40 ° C or higher, and the plankton accumulated on the plate may deteriorate the heat transfer performance. There is. Here, if 20 degreeC low temperature ballast water is heated to about 78 degreeC with a plate-type heat exchange apparatus, the low temperature ballast water after the middle of a low temperature path | route will be 49 degreeC or more. From this, if the direction in which the low-temperature ballast water flows can be reversed, even plankton adhering to the plate can be removed by receiving low-temperature ballast water of 40 ° C. or higher.

  Therefore, since the plate heat exchange device uses low-temperature ballast water and high-temperature ballast water as counterflows, the connection of the intake line to the plate heat exchange device is switched from the cold path inlet of the plate heat exchanger to the cold path outlet. , A low temperature path switching line for switching the connection of the water inlet line to the plate heat exchanger from the low temperature path outlet to the low temperature path inlet of the plate heat exchanger, and a connection of the water outlet line to the plate heat exchanger is the plate heat exchanger A high-temperature path switching line for switching from the high-temperature path inlet of the apparatus to the high-temperature path outlet, and switching the injection line connection to the rate heat exchanger from the high-temperature path outlet of the plate heat exchanger to the high-temperature path inlet; Flow direction of low-temperature ballast water and high-temperature ballast water fed to the heat exchanger Switched appropriately, the plankton is to accumulate adhering to the plate (heat transfer surface) of the plate heat exchanger device may be separated from the cold ballast water. When the flow directions of the low-temperature ballast water and the high-temperature ballast water are switched, the collision itself of the low-temperature ballast water and the high-temperature ballast water with the plate physically changes, so that an advantage of promoting the peeling of plankton attached to the plate can be obtained.

  The low-temperature path switching line branches from the intake line, connects a bypass intake line to the intake line, and provides a bypass intake line valve in the bypass intake line, branches from the downstream of the connection point of the bypass intake line to the intake line. A bypass entry water line is connected downstream from a connection point of the bypass intake line to the intake line, a bypass entry water valve is provided in the bypass entry water line, and between each connection point of the bypass intake line and the bypass entry line to the intake line. A low temperature path inlet valve can be provided, and a water inlet line valve can be provided between each connection point of the bypass water intake line and the bypass water inlet line with respect to the water inlet line. Similarly, the high-temperature path switching line branches from the water discharge line, connects the bypass water discharge line to the water injection line, and provides a bypass water discharge line valve in the bypass water discharge line, from the downstream of the connection point of the bypass water discharge line to the water injection line. A bypass water supply line is connected downstream from the connection point of the bypass water discharge line to the water discharge line, a bypass water supply line valve is provided in the bypass water supply line, and each connection point of the bypass water supply line and the bypass water supply line to the water discharge line And a high-temperature path outlet valve between each connection point of the bypass water supply line and the bypass water supply line with respect to the water injection line.

  The low-temperature path switching line and the high-temperature path switching line appropriately switch the flow direction of the low-temperature ballast water and the high-temperature ballast water fed to the plate heat exchanger as follows. First, in the forward connection, open the low-temperature path inlet valve, the incoming water line valve, the outlet water line valve and the hot-path outlet valve, and close the bypass intake line valve, the bypass inlet water line valve, the bypass outlet water line valve and the bypass water injection line valve. The water intake line is connected to the low temperature path inlet of the plate heat exchanger, the water inlet line is connected to the low temperature path outlet of the plate heat exchanger, the water discharge line is connected to the hot path inlet of the plate heat exchanger, and the water injection line is plate type Connected to the high temperature path outlet of the heat exchange device, low temperature ballast water flows from the low temperature path inlet to the low temperature path outlet, and high temperature ballast water flows from the low temperature path inlet to the low temperature path outlet. On the other hand, in the reverse connection, the low temperature path inlet valve, the water inlet line valve, the water outlet line valve and the high temperature path outlet valve are closed, and the bypass intake line valve, the bypass inlet water line valve, the bypass outlet water line valve and the bypass water injection line valve are closed. When opened, the intake line is connected to the cold path outlet of the plate heat exchanger via the bypass intake line, the inlet line is connected to the cold path inlet of the plate heat exchanger via the bypass inlet line, and the outlet line is bypassed. The hot water path is connected to the high temperature path outlet of the plate heat exchanger via the line, and the water injection line is connected to the high temperature path inlet of the plate heat exchanger via the bypass water injection line. The hot ballast water flows from the hot path outlet toward the hot path inlet.

  In this way, the low-temperature path switching line and the high-temperature path switching line directly connect the intake line, the incoming line, the outlet line, and the water injection line to the plate heat exchanger, or the intake line to the plate heat exchanger, Switching the flow direction of low-temperature ballast water and high-temperature ballast water by switching the connection of the inlet water line, outlet water line, and water injection line indirectly via the bypass water intake line, the bypass inlet water line, the bypass outlet water line, and the bypass water injection line Then, the plankton carcasses adhering to the plate (heat transfer surface) of the plate heat exchanger are peeled off.

  The present invention provides a heat recovery type purification method for ballast water that exhibits a purification capacity that satisfies the requirements of the Ballast Water Management Convention, and further, heat recovery for ballast water that can be mounted on a ship based on the purification method. A mold purification system is provided. First, the purification treatment capacity that satisfies the requirements of the Ballast Water Management Convention is to heat the low-temperature ballast water to a higher temperature than conventional heat treatment methods, for example, 80 ° C by heat exchange of low-temperature ballast water and high-temperature ballast water. It is an effect that can be obtained by doing (solving basic issues). This effect has an inventive step as a difference in absolute purification capacity compared to the conventional heat treatment method. The plate-type heat exchange device enhances the effect by high heat exchange efficiency, and makes the construction of the purification treatment system of the present invention realistic.

  The heat exchange of the low temperature ballast water and the high temperature ballast water is to recover and reuse the heat of the high temperature ballast water, thereby maximizing the use of heat in the purification treatment system. As a result, the auxiliary heating device that compensates for the amount of heat that is insufficient even after heat exchange or the amount of heat that results in heat loss can be reduced in size, and as a result, the purification processing system can be reduced in size. Further, as described above, the use of the plate heat exchange device also contributes to the downsizing of the purification processing system. As described above, the present invention brings about an effect of providing a purification processing system that can be actually mounted on a ship (solution of a prerequisite problem).

  Furthermore, the present invention is characterized in that the high-temperature ballast water is cooled simultaneously with the heating of the low-temperature ballast water because the low-temperature ballast water and the high-temperature ballast water are heat-exchanged. That is, a purification treatment method in which the high-temperature ballast water is cooled simultaneously with the heating of the low-temperature ballast water is not found in the conventional purification treatment method based on the same kind of heat treatment method. According to the present invention, the purified high-temperature ballast water is cooled and can be poured into the ballast tank as low-temperature ballast water, and the effect of not reducing the durability of the ballast tank due to heat load can be obtained. . In addition, the use of a heat exchanger that cools the high-temperature ballast water simultaneously with the heating of the low-temperature ballast water also serves to simplify the configuration of the purification treatment system. This feature also contributes to the downsizing of the purification treatment system. Yes.

  Embodiments according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an example of a purification processing system 1 according to the present invention, FIG. 2 is an exploded perspective view showing an example of a plate heat exchanger 3, and FIG. 3 is a purification process using another example of a high temperature maintaining device 5. FIG. 4 is a block diagram equivalent to FIG. 1 showing the system 1, FIGS. 4 to 8 are block diagrams equivalent to FIG. 1 showing the purification treatment procedure and drainage procedure by the purification treatment system 1 of this example, and FIG. 5 is a preliminary stage for emptying the heat exchanger 3 and the high temperature maintaining device 5, FIG. 5 is an initial processing stage for producing the first high temperature ballast water in the high temperature maintaining device 5, and FIG. FIG. 7 shows a steady processing stage in which low-temperature ballast water and high-temperature ballast water are flowed in the reverse direction of the plate heat exchanger 3, and FIG. 8 shows low-temperature ballast water from the ballast tank 8. Water draining stage represents respectively. 1 and 3 to 8 show only one ballast tank 8 as a representative for the convenience of explanation.

  As shown in FIG. 1, the purification processing system 1 of this example is composed of a coarse filtration device 25, a fine filtration device 26, a plate heat exchange device 3, a high temperature maintaining device 5, and an auxiliary heating device 52 (in FIG. 1). The intake port (sea chest) 21 and the low temperature path inlet 311 of the plate heat exchanger 3 are connected to the low temperature path outlet 312 of the plate heat exchanger 3 and the high temperature maintaining device 5 by the intake line 2. The water inlet 511 is connected to the water inlet line 4, the water outlet 512 of the high temperature maintaining device 5 is connected to the high temperature path inlet 321 of the plate heat exchanger 3 via the water outlet line 6, and the plate type heat exchanger 3 is connected to the high temperature path outlet. 322 and the water injection port 81 of the ballast tank 8 are connected by the water injection line 7 respectively. Further, in order to switch the flow direction of the low-temperature ballast water and the high-temperature ballast water to be sent to the plate-type heat exchange device 3, the bypass heat intake line 28, the bypass inlet water line 43, the bypass outlet water line 64, and the bypass water injection to the plate heat exchanger 3 A line 73 is provided. In addition, the purification treatment system 1 of the present example takes the low-temperature ballast water pumped up when the flow rate of the ballast water pump 23 is reduced and the drainage line 9 and the detour drainage line 92 for draining the low-temperature ballast water from the ballast tank 8. A pump bypass line 231 for refluxing 21 is provided. The pump bypass line 231 can be opened and closed by a pump bypass line valve 232.

The intake line 2 is provided with a ballast water pump 23, a coarse filtration device 25, and a fine filtration device 26 in order from the upstream side in the forward steady processing stage, and the intake port 21 and the low-temperature path inlet 311 of the plate heat exchange device 3 Connect. The ballast water pump 23 is used for pumping low temperature ballast water (seawater) from the water intake 21 and sending it to the plate heat exchanger 3 during the purification process, and for discharging low temperature ballast water (so-called ballast water) from the ballast tank 8. It is done. For example, if the ship has a ballast tank 8 with a capacity of 10,000 m ^{3 to} 20,000 m ³ , the ballast water pump 23 only needs to have a capacity of 30 m head and a flow rate of about 600 m ³ / h. A water intake valve 22 is provided between the water intake 21 and the ballast water pump 23 to open and close the water intake line 2. The coarse filtration device 25 uses a centrifugal filtration device. The coarse filtration device 25 reduces the burden on the fine filtration device 26 and extends the life and backwash period of the fine filtration device 26. The drain line 9 is connected between the ballast water pump 23 and the intake valve 22 of the intake line 2. The bypass drainage line 92 connects the intake line 2 and the intake port 21 by bypassing the ballast water pump 23 from the upstream side of the intake line valve 24 provided between the ballast water pump 23 and the coarse filtration device 25. A detour drain line valve 93 is provided so that it can be opened and closed freely. When pumping low temperature ballast water, the intake line valve 24 is opened and the bypass drainage line valve 93 is closed. When low temperature ballast water is drained from the ballast tank 8, the intake line valve 24 is closed and the bypass drainage line valve 93 is opened.

  The microfiltration device 26 uses an anthracite filtration device. Anthracite filtration equipment has the ability to remove 98 to 99% of plankton in terms of number, especially 99% or more of large plankton (zooplankton) in terms of weight. Can be maintained. The microfiltration device 26 constituted by such an anthracite filtration device maintains the function of the plate heat exchange device 3, and greatly reduces the number and amount of plankton killed by the high temperature maintenance device 5. The microfiltration device 26 of this example is provided with a microfiltration device valve 261 on the upstream side so that low-temperature ballast water does not flow in during the preparation stage, and a microfiltration device drain 262 that drains the low-temperature ballast water remaining in the preparation stage. ing.

  As shown in FIG. 2, the plate-type heat exchange device 3 of the present example has a plurality of plates (heat transfer surfaces) 33 closely arranged and integrated so as to form a narrow inter-plate flow path. The low-temperature ballast water (see the broken arrow) and the high-temperature ballast water are alternately passed from the low-temperature path 31 or the high-temperature path 32 to the inter-plate flow paths that pass through the low-temperature path 31 and the high-temperature path 32. (Refer to the solid line arrow) is sent as a counter flow (a flow in which the directions of flow are opposite to each other). The low-temperature path 31 and the high-temperature path 32 are provided with holes in communication with every other inter-plate flow path, and the low-temperature ballast water and the high-temperature ballast water flow into the inter-plate flow paths from the holes. Then, heat exchange is performed between the low-temperature ballast water and the high-temperature ballast water through the plate 33 that defines the flow path between the plates.

The plate heat exchange device 3 can heat the low-temperature ballast water to a temperature 2 ° C. lower than the high-temperature ballast water with a configuration having the best heat exchange efficiency. Since the temperature of the suitable high temperature ballast water by the purification processing system 1 of this invention is 80 degreeC or more, low temperature ballast water should just be heated to about 78 degreeC at the minimum. For example, when the ballast water pump 23 flows low-temperature ballast water and high-temperature ballast water with a flow rate of 600 m ³ / h, in order to reliably exchange heat with the low-temperature ballast water and high-temperature ballast water at the flow rate, the plate heat exchanger 3 The total heat transfer surface of the plate 33 may be 2,000 m ² in total. Since the standard marine product currently found has a heat transfer surface of 2 m ² , about 1,000 plates 33 (see FIG. 2) forming the heat transfer surface are required. Here, if the plate 33 is a 0.5 mm thick titanium plate and each plate 33 is 5 mm or less including the thickness, the size of the plate heat exchange device 3 is less than 5 m and can be mounted on a ship sufficiently. . However, it is not practical to configure the plate type heat exchange device 3 by arranging the plates 33 integrally. Therefore, in actuality, the configuration shown in FIG. 2 is used as a heat exchange unit, and the low-temperature path outlet 312 of the preceding heat exchange unit is connected to the low-temperature path inlet 311 of the subsequent heat exchange unit, and the subsequent heat exchange is performed. A plate-type heat exchange device 3 having a multi-stage configuration in which the high-temperature path outlet 322 of each unit is connected to the high-temperature path inlet 321 of the preceding heat exchange unit. For example, when the 1,000 plates 33 are used, seven or eight heat exchanger units each having 125 plates 33 are connected. 1 and 3 to 8 show such a plate-type heat exchange device 3 having a multi-stage configuration as an integral unit. The plate-type heat exchange device drain 34 for emptying the plate-type heat exchange device 3 is provided for each heat exchange device (only one is shown in the drawing for convenience).

  The incoming water line 4 is provided with an incoming water line surge tank 41 and an incoming water line valve 42 in order from the upstream side in the forward steady processing stage. The low temperature path outlet 312 of the plate heat exchanger 3 and the inlet 512 of the high temperature maintenance device 5 are provided. And connect. The incoming water line surge tank 41 is paired with a later-described outgoing water line surge tank 63 to absorb the pressure fluctuation of the hot ballast water flowing into the stationary tank 51 of the high temperature maintaining device 5 and to be retained in the stationary tank 51. Stabilize the water condition. The incoming water line valve 42 is interlocked with a low temperature path inlet valve 27 described later and opens / closes exclusively with a bypass water intake line valve 281 and a bypass incoming water line valve 431 described later. Specifically, when low-temperature ballast water is poured into the plate heat exchanger 3 in the forward direction, the water inlet line valve 42 and the low temperature path inlet valve 27 are opened, and the bypass water intake line valve 281 and the bypass water inlet line valve 431 are closed. Conversely, when low-temperature ballast water is poured into the plate heat exchanger 3 in the reverse direction, the water inlet line valve 42 and the low temperature path inlet valve 27 are closed, and the bypass water intake line valve 281 and the bypass water inlet line valve 431 are opened.

  The bypass water intake line 28 and the bypass water intake line 43 constitute a low-temperature path switching line. The bypass intake line 28 branches from the upstream side of the low temperature path inlet valve 27 provided in the intake line 2 and is connected to the upstream side of the incoming line valve 42 provided in the incoming line 4. The bypass water intake line 43 branches from the downstream side of the water inlet line valve 42 provided in the water inlet line 4 and is connected to the downstream side of the low temperature path inlet valve 27 provided in the water intake line 2. Further, in order to prevent the low-temperature ballast water from flowing into the bypass intake line 28 and the bypass inlet water line 43 in the steady treatment stage in which the low-temperature ballast water flows in the forward direction, a bypass intake line valve 281 is provided in the bypass intake line 28, and A bypass water inlet line valve 431 is provided in the bypass water inlet line 43. Opening and closing of the bypass water intake line valve 281 and the bypass water intake line valve 431 is as described above.

  The high temperature maintaining device 5 of the present example is composed of a closed type retaining tank 51 that retains high temperature ballast water. By using the closed tank 51 as a sealed type, the heat retaining property of the high temperature ballast water to be stopped is improved. In this example, a steam line 521 for flowing steam from a boiler which is an auxiliary heating device 52 is extended into the retaining tank 51, and heat of steam flowing in the steam line 521 is used to heat high-temperature ballast water that does not reach a predetermined sterilization temperature. The temperature of the high temperature ballast water in the stopping tank 51 is prevented from decreasing. The steam line 521 is provided with a steam line valve 522 that blocks the flow of steam when not in use. In addition, the stationary tank 51 is provided with a stirring propeller 513 so that the temperature distribution of the high-temperature ballast water does not vary due to convection. However, since it is inevitable that the temperature distribution of the high-temperature ballast water will vary, there is no way for the inlet 511 to be provided at the bottom of the tank 51, and the outlet 512 to be provided at the top of the tank 51. That is, the high-temperature ballast water that has been subjected to the purification process by the heat treatment method is allowed to flow out from the water outlet 512. In addition, the high-temperature ballast water poured into the retention tank 51 is efficiently heated by the auxiliary heating device 52, and the heated high-temperature ballast water is retained only for the predetermined sterilization time. A partition plate may be provided in the stopping tank 51 to form a path from the water inlet 511 to the water outlet 512. In addition, the stopping tank 51 of this example is provided with a stopping tank drain 514 for draining the remaining low-temperature ballast water and a pressure relief valve 515 for releasing the pressure in the closed stopping tank 51.

  The high temperature maintaining device 5 may maintain the temperature of the high temperature ballast water heated for the time necessary for the purification treatment, and does not necessarily need to use the retaining tank 51 as described above. For example, as shown in FIG. 3, the high temperature maintaining device 5 may be configured from a stopping pipeline 53 that connects the water inlet 531 and the water outlet 532 with such a length that the high temperature ballast water flows for a predetermined time while maintaining the temperature. The stopping tank 51 provided with the partition plate can be regarded as a configuration in which a stopping pipeline 53 is formed in the stopping tank 51. The stationary pipeline 53 can drain the high-temperature ballast water remaining from the stationary pipeline drain 533. In another example, the high-temperature maintaining device 5 has a heating wire 541 of an auxiliary heating device 54 serving as an electrical heating source wound around a stationary pipeline 53 immediately after a water inlet 531, and the heating wire 541 satisfies a predetermined sterilization temperature. The high-temperature ballast water is heated, and the temperature of the high-temperature ballast water is prevented from being lowered while flowing the high-temperature ballast water along the stationary pipeline 53 provided with a heat insulating coating. In this another example of the high temperature maintaining device 5, since the high temperature ballast water always flows, there is little possibility that dead plankton or the like is deposited or accumulated. However, in order to secure a predetermined time for the high temperature ballast water to flow as the flow rate of the high temperature ballast water increases, the stop pipeline 53 becomes longer and the installation space becomes larger. A high temperature maintaining device 5 (see FIG. 1) composed of a holding tank 51 is preferable.

  The water discharge line 6 is provided with a water discharge line filter 62, a water discharge line valve 61, and a water discharge line surge tank 63 in order from the upstream side in the forward steady processing stage, and the water outlet 512 of the high temperature maintaining device 5 and the plate heat exchanger 3 Is connected to the hot path inlet 321. The water discharge line filter 62 is a filtration device for preventing plankton or the like in the high temperature ballast water killed in the high temperature maintaining device 5 from flowing into the plate heat exchange device 3. The water discharge line valve 61 is interlocked with a high temperature path outlet valve 71 described later, and opens / closes exclusively with a bypass water discharge line valve 641 and a bypass water injection line valve 731 described later. The incoming water line 4 is not provided with a filtration device because plankton must be poured into the high temperature maintaining device 5 together with the high temperature ballast water. The discharge line surge tank 63 is paired with the above-described incoming line surge tank 41 to absorb the pressure fluctuation of the high-temperature ballast water flowing out from the stop tank 51 of the high-temperature maintenance device 5, and the high temperature retained in the stop tank 51. Stabilize the state of ballast water.

  The water injection line 7 is provided with a high temperature path outlet valve 71 and a water injection line valve 72 in order from the upstream side in the forward steady processing stage, and a high temperature path outlet 322 of the plate heat exchanger 3 and a water injection port 81 of the ballast tank 8 Connect. The ballast tank 8 is provided with a water inlet valve 82 that can be opened and closed between the inlet 81 and the water injection line 7 in order to hold the injected low temperature ballast water. Further, in order to drain low temperature ballast water from the ballast tank 8, the drainage line 9 is branched from the downstream side of the water injection line valve 72 of the water injection line 7, and is connected to the upstream side of the ballast water pump 23 of the water intake line 2. The drainage line 9 is provided with a drainage line valve 91 in the vicinity of the connection point with the intake line 2, interlocked with the bypass drainage line valve 93, and opened and closed exclusively with the intake line valve 24. Switching between pumping up the low temperature ballast water and draining the low temperature ballast water from the ballast tank 8. The high-temperature path outlet valve 71 is linked to the above-described water discharge line valve 61 and opens and closes exclusively with a bypass water intake line valve 281 and a bypass water intake line valve 431 described later. Specifically, when high-temperature ballast water flows out from the plate heat exchanger 3 in the forward direction, the water discharge line valve 61 and the high-temperature path outlet valve 71 are opened, and the bypass water discharge line valve 641 and the bypass water injection line valve 731 are closed. Conversely, when high-temperature ballast water is poured into the plate heat exchanger 3 in the reverse direction, the water discharge line valve 61 and the high temperature path outlet valve 71 are closed, and the bypass discharge water line valve 641 and the bypass water injection line valve 731 are opened.

  The bypass water discharge line 64 and the bypass water injection line 73 constitute a high-temperature path switching line. The detour water discharge line 64 branches from the upstream side of the water discharge line valve 61 provided in the water discharge line 6, that is, between the water supply line valve 61 and the water discharge line filter 62, and is connected to the high-temperature path outlet valve 71 provided in the water injection line 7. Connected upstream. The detour water injection line 73 branches from the downstream side of the high temperature path outlet valve 71 provided in the water injection line 7 (in this example, it is considerably downstream from the high temperature path outlet valve 71 for convenience of illustration), 6 is connected to the downstream side of the water discharge line valve 61 provided in FIG. Further, in order to prevent the high temperature ballast water from flowing into the bypass water discharge line 64 and the bypass water injection line 73 in the steady treatment stage in which the high temperature ballast water flows in the forward direction, a bypass discharge water line valve 641 is provided in the bypass water discharge line 64, and A bypass water injection line valve 731 is provided in the bypass water injection line 73. Opening and closing of the bypass water discharge line valve 641 and the bypass water injection line valve 731 is as described above.

  The purification processing system 1 of this example is used according to the following procedure. In the preparatory stage shown in FIG. 4, low temperature ballast water remaining in each device is drained in the previous purification process. Specifically, the microfiltration device 26, the plate-type heat exchange device 3 where the low-temperature ballast water is likely to remain, and the microfiltration device drain 262, the plate-type heat exchange device drain 34 provided in the stationary tank 51 of the high-temperature maintenance device 5, respectively. Then, the storage tank drain 514 is opened, and the low-temperature ballast water remaining in the storage tank 51 of the microfiltration device 26, the plate heat exchange device 3, and the high-temperature maintenance device 5 is drained. After drainage of low-temperature ballast water is confirmed or after a certain period of time has elapsed after opening each drain 262, 34, 514, the microfiltration device drain 262, the plate heat exchanger drain 34, and the storage tank drain 514 are closed and ready. Finish stage processing.

The preparatory treatment stage seen in FIG. 5 generates high temperature ballast water for use in the plate heat exchanger 3. For this reason, the tank 51 of the high temperature maintaining device 5 opens the incoming water line valve 42, closes the outgoing water line valve 61 and the stationary tank drain 514, opens the pressure relief valve 515, and cools the low-temperature ballast water flowing from the incoming water line 4. Stop. In this preparatory process stage, since there is no heat exchange by the plate type heat exchange device 3, low temperature ballast water that is not heated is poured into the stationary tank 51 of the high temperature maintenance device 5. Then, the water intake valve 22, the water intake line valve 24, the microfiltration device valve 261 and the low temperature path inlet valve 27 are opened, and the water intake line 2 and the water intake line 4 provided with the valves are connected to operate the ballast water pump 23. By doing so, the low-temperature ballast water pumped up from the water intake 21 is poured into the stop tank 51 of the high-temperature maintenance device 5 through the water intake line 2 and the water intake line 4. For example, if the capacity of the storage tank 51 is about 30 m ³ and the capacity of the ballast water pump 23 is 600 m ³ / h, low temperature ballast water (about 27 m ³ , see below) that stops in the storage tank 51 in the steady processing stage. The time required to enter the water is less than 3 minutes.

In the preparation processing stage, the low-temperature ballast water retained in the retention tank 51 is further heated to kill plankton and bacteria contained in the low-temperature ballast water, and high-temperature ballast water used for heat exchange in the plate heat exchange device 3 Generate. Steam supplied from the auxiliary heating device 52 is used for heating the low-temperature ballast water. For example, if the low temperature ballast water is 20 ° C. and the target high temperature ballast water is 80 ° C., the low temperature ballast water may be raised by 60 ° C. by the auxiliary heating device 52. Here, when the temperature of the low-temperature ballast water is increased, the volume of the high-temperature ballast water increases from that of the low-temperature ballast water. Therefore, the low-temperature ballast water stopped in the stop tank 51 takes into account the volume increase of the stop tank 51. Keep it less. For example, in the case of the retaining tank 51 having a volume of 30 m ³ , the low temperature ballast water to be retained is practically about 27 m ³ .

The low-temperature ballast water retained in the retention tank 51 may be heated to a high-temperature ballast water by a separate dedicated heating device. For example, the ability to raise the high-temperature ballast water heated by the plate heat exchanger 3 by 2 ° C. If only the auxiliary heating device 52 is used, when the temperature of the low-temperature ballast water of about 27 m ³ is raised from 20 ° C. to 80 ° C., the heating time is about 2 hours or less. For this reason, if the auxiliary heating device 52 uses steam and is dedicated to the purification processing system 1, in order to reduce the processing time required for the preparatory processing stage, the auxiliary heating device 52 is operated before the preparatory stage, It is desirable to generate When the generation of the high-temperature ballast water is completed in this way, the pressure relief valve 515 in the stopping tank 51 is closed.

Subsequently, the water discharge line valve 61 is opened, the high-temperature path outlet valve 71 is closed, and the high-temperature ballast water generated in the stopping tank 51 is poured into the high-temperature path 32 (see FIG. 2) of the plate heat exchange device 3. Fill 32 with hot ballast water. At this time, the high temperature ballast water in the tank 51 is reduced by the amount poured into the plate heat exchange device 3, so the low temperature ballast water must be replenished and heated again. For example, if the total volume of the high temperature path 32 of the plate heat exchanger 3 and the flow path between the plates 33 is 5 m ³ , it takes 2 hours to heat the low temperature ballast water of 27 m ³ and 20 ° C. to 80 ° C. If it was weak, it would take about 20 minutes to heat the replenished low temperature ballast water. Actually, heat exchange starts between the low-temperature ballast water and the high-temperature ballast water facing each other across the plate 33 (see FIG. 2) of the plate-type heat exchange device 3, and the temperature of the low-temperature ballast water becomes high, so that it is replenished. The time required for heating the low temperature ballast water is shortened. When heating the replenished low temperature ballast water, the pressure relief valve 515 is appropriately opened to release the pressure in the retention tank 51.

  Thus, when the plate type heat exchange device 3 is ready for continuous heat exchange of the low temperature ballast water and the high temperature ballast water, the high temperature path outlet valve 71 is opened and the water injection line 7 connected to the ballast tank 8 is communicated. Pumping of the low temperature ballast water is continuously started by the ballast water pump 23, and the process proceeds to the steady treatment stage shown in FIG. It seems that the temperature of the high-temperature ballast water in the stop tank 51 temporarily decreases again due to the low-temperature ballast water poured into the stop tank 51 during the transition from the preparation process stage to the steady process stage. However, when the low-temperature ballast water replenished in the storage tank 51 in the preparatory processing stage is heated, the low-temperature ballast water remaining in the plate heat exchange device 3 is considerably balanced with the high-temperature ballast water by heat exchange. Therefore, the temperature of the high-temperature ballast water in the retaining tank 51 does not temporarily decrease or hardly causes a problem.

  In the steady treatment stage, the 20 ° C low temperature ballast water pumped from the intake 21 is heated to about 78 ° C high temperature ballast water, and further, the auxiliary heating device 52 in the high temperature maintaining device 5 is used as the 80 ° C high temperature ballast water for heat treatment. The process until the high temperature ballast water is cooled again to a low temperature ballast water of about 22 ° C. and poured into the ballast tank 8 will be described. The low-temperature ballast water is pumped from the sea through the water intake 21 by the ballast water pump 23 and is poured into the water intake line 2. The low-temperature ballast water is equal to the water temperature of the sea area to be pumped, but is assumed to be 20 ° C. in this example. The intake port 21 is usually provided with a coarse filter, and large dust is removed from the pumped low temperature ballast water. The low-temperature ballast water is further removed through the coarse filtration device 25 and small dust, and through the microfiltration device 26, large plankton. Thus, the low temperature ballast water containing only small plankton and bacteria is poured into the low temperature path inlet 311 of the plate heat exchanger 3. The temperature of the low temperature ballast water so far is 20 ° C.

  The plate heat exchanger 3 exchanges heat between 20 ° C. low-temperature ballast water poured from the water intake line 2 and 80 ° C. high-temperature ballast water poured from the water discharge line 6. Specifically, the 80 ° C. high temperature ballast water recovers heat and is cooled until it flows out of the high temperature path outlet 322 to become a low temperature ballast water of about 22 ° C., and the 20 ° C. low temperature ballast water is the recovered heat. Is heated until it flows out of the low temperature path outlet 312 and becomes high-temperature ballast water of about 78 ° C. The high temperature maintaining device 5 pours high temperature ballast water of about 78 ° C. heated by the plate heat exchange device 3 into the retaining tank 51, and further heats the high temperature ballast water by the heating of the auxiliary heating device 52 for purification treatment. A high temperature ballast water at a temperature of 80 ° C. is used, and the high temperature ballast water at 80 ° C. is retained for a predetermined sterilization time (for example, 3 minutes or more), and plankton and bacteria are killed by a heat treatment purification process.

The high-temperature ballast water at 80 ° C. retained in the retaining tank 51 of the high-temperature maintaining device 5 for a predetermined sterilization time flows out from the water outlet 512 and then flows into the plate heat exchanger 3 through the water outlet line 6. The 80 ° C. high temperature ballast water exchanges heat with the 20 ° C. low temperature ballast water poured from the intake line 2 to recover and cool the heat, and a plate type heat exchange device as low temperature ballast water of about 22 ° C. 3 flows out from the hot route outlet 322 to the water injection line 7. Since the low-temperature ballast water at about 22 ° C. has already been purified by the heat treatment method, almost all plankton and bacteria have been killed. Here, the dead plankton is removed by the water supply line filter 62 and is not transported to the ballast tank 8 through the water injection line 7. The time that the ballast tank 8 is filled with the low-temperature ballast water thus poured depends on the ability of the ballast water pump 23 to determine the flow rates of the low-temperature ballast water and the high-temperature ballast water. For example, when the capacity of the ballast water pump 23 is 600 m ³ / h and the capacity of the ballast tank 8 is 20,000 m ³ , it takes less than 40 hours to fill the ballast tank 8 with a low temperature ballast water of about 22 ° C.

  The steady processing stage ends when, for example, the low-temperature ballast water that has been subjected to the purification processing is poured into all of the plurality of ballast tanks 8. However, at the time point, the low-temperature path 31 (see FIG. 2) of the water intake line 2 and the plate heat exchanger 3 is made of low temperature ballast water, and the water inlet line 4, the high temperature maintenance device 5, the water outlet line 6, and the plate heat exchanger. 3 hot path 32 (see FIG. 2), and the irrigation line 7 remain filled with hot ballast water. In particular, since low-temperature ballast water has not been purified, it cannot be left as it is. Therefore, the low-temperature ballast water and high-temperature ballast water remaining in each line and each apparatus after the steady treatment stage are the low-temperature ballast remaining from the intake line 2 to the water injection line 7 as in the later-described drainage stage (see FIG. 8). It is desirable to drain water and high temperature ballast water from the ship.

  As described above, the high-temperature ballast water that has been subjected to the purification treatment no longer contains plankton or bacteria, and the dead plankton has been removed by the water discharge line filter 62. Therefore, the high-temperature path 32 of the plate heat exchanger 3 is used. There is no possibility that plankton may adhere to the plate (heat transfer surface) 33 forming the inter-plate flow path (see FIG. 2) communicating with the high temperature path 32. However, the flow path between the plates 33 (see FIG. 2) between the low temperature path 31 of the plate heat exchanger 3 and the plate 33 communicating with the low temperature path 31 is plankton in the section where the low temperature ballast water is less than 40 ° C. during the heating. On the contrary, the plankton peels off in the section above 40 ° C. Therefore, the present invention prevents the plankton from adhering by switching the flow direction of the low temperature ballast water and the high temperature ballast water. The steady processing stage in the reverse direction seen in FIG. 7 is a steady processing stage in a state where the flow directions of the low temperature ballast water and the high temperature ballast water are switched.

  The flow direction of the low-temperature ballast water and high-temperature ballast water is to close the low-temperature path inlet valve 27, the water inlet line valve 42, the water outlet line valve 61 and the high-temperature path outlet valve 71, the bypass water intake line valve 281, the bypass water inlet line valve 431, the bypass water By opening the line valve 641 and the bypass water supply line valve 731, the intake line 2 is connected to the low temperature path outlet 312 via the bypass water intake line 28, and the incoming water line 4 is connected to the low temperature path inlet 311 via the bypass water intake line 43. Then, the water discharge line 6 is connected to the high temperature path outlet 322 via the bypass water discharge line 64 and the water injection line 7 is connected to the high temperature path inlet 321 via the bypass water injection line 73. As a result, in the plate heat exchange device 3, the low-temperature ballast water and the high-temperature ballast water flow in the direction opposite to the normal direction, and the plate (see FIG. 2) that forms the low-temperature path 31 and the inter-plate flow path (see FIG. Plankton adhering to the heat transfer surface (33) can be removed. Here, the dead plankton is removed by the water discharge line filter 62 and is not carried to the ballast tank 8 through the water injection line 7, as in the normal processing step in the forward direction. Such path switching for the purpose of removing plankton may be performed when a decrease in the heat exchange efficiency of the plate heat exchange device 3, specifically, when an increase in temperature difference is sensed via the plate 33. .

  The drainage stage seen in FIG. 8 drains the low temperature ballast water directly from the ballast tank 8 as in the current ballast water treatment apparatus. Specifically, the intake line valve 24, the intake valve 22 and the water injection line valve 72 are closed to prevent the low-temperature ballast water from flowing back to the water intake line 2 and the water injection line 7 (the pump bypass line valve 232 is in a normal state). The drainage line valve 91 and the bypass drainage line valve 93 are opened, the ballast tank 8 is communicated with the water intake 21 via the drainage line 9 and the bypass drainage line 92, and the ballast tank 8 is Drain low temperature ballast water from

It is a block diagram showing an example of the purification processing system based on this invention. It is an exploded perspective view showing an example of a plate type heat exchange device. It is a block diagram equivalent to FIG. 1 showing the purification processing system using the high temperature maintenance apparatus of another example. It is a block diagram equivalent to FIG. 1 showing the preparatory stage which empties a microfiltration apparatus, a plate-type heat exchange apparatus, and a high temperature maintenance apparatus. FIG. 2 is a block diagram corresponding to FIG. 1 showing an initial processing stage for producing the first high-temperature ballast water by the high-temperature maintenance device. It is a block diagram equivalent to FIG. 1 showing the steady process stage which flows low temperature ballast water and high temperature ballast water in the forward direction of a plate-type heat exchange apparatus. It is a block diagram equivalent to FIG. 1 showing the steady process stage which flows low temperature ballast water and high temperature ballast water in the reverse direction of a plate-type heat exchange apparatus. It is a block diagram equivalent to FIG. 1 showing the drainage step which drains low temperature ballast water from a ballast tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Purification processing system 2 Intake line 3 Plate type heat exchange device 4 Inlet line 5 High temperature maintenance device 6 Outlet line 7 Injecting line 8 Ballast tank 9 Drainage line

Claims (8)

A method for purifying ballast water that heats ballast water and kills plankton and bacteria in the ballast water, comprising high-temperature ballast water that has been purified by a heat treatment method and low-temperature ballast water that has been pumped from the intake port. The low-temperature ballast water that has been heat-exchanged and pumped from the water intake is heated by the heat recovered from the high-temperature ballast water that has been purified by the heat treatment method, and is converted to high-temperature ballast water before being purified by the heat treatment method. The heat recovery type purification method for ballast water, characterized in that the high-temperature ballast water that has been purified by the above-mentioned process is low-temperature ballast water that is cooled by recovering heat and fed to the ballast tank. The heat recovery type purification method for ballast water according to claim 1, wherein the heat exchange between the high-temperature ballast water after the purification treatment by the heat treatment method and the low-temperature ballast water pumped from the intake port is performed by a plate heat exchange device. The low-temperature ballast water pumped up from the water intake is heated by the heat recovered from the high-temperature ballast water after being purified by the heat treatment method, and then further heated by the auxiliary heating device before being purified by the heat treatment method. The heat recovery type purification method for ballast water according to claim 1, wherein the ballast water is high-temperature ballast water. A system for purifying ballast water that heats ballast water to kill plankton and bacteria in the ballast water. A plate-type heat exchange device for heat exchange, a high-temperature maintenance device for maintaining the temperature of the high-temperature ballast water obtained by heating the low-temperature ballast water by the plate-type heat exchange device for the plankton or sterilization death time, the intake port, A water intake line connecting the low temperature path inlet of the plate heat exchanger, a water inlet line connecting the low temperature path outlet of the plate heat exchanger and the water inlet of the high temperature maintaining apparatus, a water outlet of the high temperature maintaining apparatus, and the above A water discharge line connecting the hot path inlet of the plate heat exchanger, and the hot path outlet and ballast of the plate heat exchanger Heat recovery type water treating system of the ballast water, characterized in that it is composed of a water injection line connecting the links of the water inlet. The plate heat exchanger is composed of a plurality of heat exchanger units each having a low temperature path inlet, a low temperature path outlet, a high temperature path inlet, and a high temperature path outlet. The heat recovery type purification system for ballast water according to claim 4, wherein the system is connected to the low-temperature path inlet of the exchange unit, and the high-temperature path outlet of the subsequent heat exchange unit is connected to the high-temperature path inlet of the preceding heat exchange unit. The high-temperature maintenance device is an auxiliary heating device between the water inlet and the water outlet that further heats the high-temperature ballast water fed from the plate heat exchange device through the water inlet line and converts it into high-temperature ballast water before being purified by the heat treatment method. The heat recovery type purification treatment system for ballast water according to any one of claims 4 and 5, which is provided in the above. The heat recovery type purification system for ballast water according to any one of claims 4 to 6, wherein the water intake line has a filtration device provided between the water inlet and the low temperature path inlet of the plate heat exchange device. The connection of the intake line to the plate heat exchanger is switched from the cold path inlet of the plate heat exchanger to the cold path outlet, and the connection of the water intake line to the plate heat exchanger is switched from the cold path outlet of the plate heat exchanger. The connection of the low temperature path switching line for switching to the low temperature path inlet and the connection of the water outlet line to the plate heat exchanger from the high temperature path inlet of the plate heat exchanger to the hot path outlet, and connection of the water injection line to the plate heat exchanger A heat recovery type purification system for ballast water according to any one of claims 4 to 7, further comprising a high-temperature path switching line for switching from a high-temperature path outlet to a high-temperature path inlet of the plate heat exchanger.

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