KR101724166B1 - Filtfering unit and ballast water production equipment provided with same - Google Patents

Abstract

A filtration system (1) in a ballast water producing system for a ship (S), comprising a filtration unit (4) for filtering raw water (RW) received in a vessel (S) and supplying it to a ballast tank (6) A gas supply passage 12 for supplying compressed air A to the depth filter 10 for forming a filtration film in the filtration unit 4 and the depth filter 10 connected to the filtration unit 4, And a discharge passage 14 for discharging the compressed air A to the outside of the ship S together with the raw water RW in the depth filter 10 and a hole diameter of the filtration film forming the depth filter 10 1 to 25 탆.

Description

TECHNICAL FIELD [0001] The present invention relates to a filtering unit and a ballast water producing apparatus having the filtration unit.

The present application is based on Japanese Patent Application No. 2009-32872 filed on February 16, 2009, Japanese Patent Application No. 2009-185223 filed on August 7, 2009, Japanese Patent Application No. 2009-189188 filed on August 18, 2009 , And Japanese Patent Application No. 2009-205570, filed on September 7, 2009, which are hereby incorporated by reference in their entirety.

The present invention relates to an apparatus for producing ballast water to be mounted on a ship, for example a cargo ship.

For example, in a ship, particularly a cargo ship, measures are taken to stabilize the ship by loading seawater into the ballast tank formed in the ship to lower the center of gravity of the ship when no cargo is loaded. The ballast water is discharged from the ship when the cargo is loaded at the stopping port. In the outer vessel, the aquatic organisms contained in the ballast water are pointed out as a problem affecting the ecosystem as alien species.

Recently, in order to solve the problem of such ballast water, international regulations on the discharge of ballast water have been made. Specifically, it regulates the number of plankton (mainly zooplankton) of 50 탆 or more, plankton (mainly phytoplankton) and fungi (E. coli, enterococci etc.) contained in ballast water. A treatment method for satisfying these regulations is usually carried out by a combination of mechanical treatment such as filtration, cavitation by which plankton is killed by high-speed and high-pressure jet, and chemical treatment by injecting medicines and ozone (for example, For example, non-patent document 1).

 Maritime Compass Bimonthly Compass September 2007 Issue 32-39

In the above-described conventional ballast water producing apparatus, the hole diameter of the filter for filtration was about 50 탆 which is relatively large. This is because if the hole diameter is small, clogging tends to occur, and the filtering area of the filter needs to be increased in order to avoid this, so that the apparatus becomes large and becomes disadvantageous in mounting the vessel. Plankton having a diameter of 50 μm or less is sprayed with seawater at a high pressure and a high pressure, and the plankton is crushed and treated by cavitation or drug administration.

However, in the treatment by cavitation, since the power is exaggerated and the number of plankton is reduced more than necessary because the seawater is blown out at a high pressure and high pressure, there is a fear that the ecosystem of the sea on which the ballast water is loaded is influenced. In addition, when plankton is treated with medicines or the like, a large amount of medicines are required, and the processing cost becomes high every time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a filtration unit capable of removing particulates and capable of suppressing initial introduction cost and maintenance cost to a low level, And which is small in size and can be kept at a low processing cost.

In order to achieve the above object, a filtration unit according to the present invention is a filtration unit comprising a filter medium and a casing for accommodating the filter medium, wherein the casing comprises a raw water supply port for supplying raw water to the filter medium, A fluid supply port for supplying a fluid for backwashing, a fluid backwashing the filter medium and an outlet for discharging the raw water, and the filter medium is a depth filter having a pore diameter of 1 to 25 μm. As the fluid for the reverse osmosis, a gas or a liquid is used, preferably a gas, more preferably an inert gas such as air or nitrogen.

The hole diameter is defined as follows. A solution prepared by adding 10,000 particles / liter of particles having a certain diameter, preferably spherical polystyrene or glass beads in water, was applied to a depth filter (outer diameter 60 mm, inner diameter 30 mm, length 250 mm) at 25 DEG C and 1.0 m < (R%) obtained by dividing the difference in the number of particles present in the liquid before and after the water flow by the number of particles present in the liquid before the water flow was measured with an optical counter (S) of particles having R of 80 in the following approximate formula (1) is determined based on the measured values, and this value is used as a pore diameter.

R = 100 / (1 - m x exp {-a x log (S)}) (1)

Here, m and a are constants determined by the constants of the depth filter.

For example, when the diameter of the particles is 1 占 퐉, a solution to which spherical polystyrene fine particles (10,000 / L) is added is applied to a depth filter (outer diameter 60 mm, inner diameter 30 mm, length 250 mm) Can be measured.

According to this configuration, since the depth filter having a pore diameter of 1 to 25 占 퐉 is used for the filter medium, it is possible to remove the small plankton, and the initial introduction cost can be suppressed as compared with the case of using the surface filter. In addition, since the filtration performance of the filter medium can be restored and used by backwash cleaning, the frequency of replacement of the filter medium can be reduced and the maintenance cost can be suppressed.

In the present invention, it is preferable that the fluid supply port and the filtrate discharge port are the same. According to this configuration, the fluid supply port and the filtrate discharge port can be made common to simplify the configuration.

In the present invention, it is preferable that the filter medium is integrally formed by fixing both ends of a plurality of filters with a fixing plate. According to this configuration, by combining a plurality of depth filters, the filtration area becomes large, and since the plurality of depth filters become one sub-unit by integration, the replacement of the filter medium becomes easy.

In the present invention, the filter medium may be arranged so as to be inclined at an inclination angle of 20 to 70 DEG below the inclination toward the filtered water outlet. According to this configuration, since the filtration unit is located at the opposite side of the filtration water outlet from the filtration unit, for example, when the raw water is filtered after backwash cleaning by the gas, the gas in the casing is easily discharged from the opposite side , And there is less possibility that air is mixed into the filtered water. When the inclination angle is excessively large, the vertical dimension of the filtration unit becomes large. Therefore, a large space is required for extracting the filter medium above the filtration unit during maintenance such as separation. If the inclination angle is excessively small, .

In the present invention, the filter medium may be disposed so as to be inclined at an inclination angle of 20 to 70 degrees upward from the filtration water outlet port. According to this configuration, since the opening end of the depth filter located on the side of the filtered water outlet port is opened upward, the air in the vicinity of the closed end of the lower depth filter is discharged from the opening end, The air can be prevented from remaining, and the filtration can be efficiently performed using the entire depth filter.

In the present invention, it is preferable that the discharge port is formed above the raw water supply port. According to this configuration, when raw water is supplied into the filtration unit at the time of initial operation or backwashing with the gas, and the so-called "air discharge" is performed in the unit, the gas in the filtration unit is smoothly discharged.

A ballast water producing apparatus according to the present invention has a filtration unit according to the present invention and supplies filtered water taken out from the filtration unit as ballast water to a ballast tank of a ship, A fluid supply passage connected to the supply port for supplying a fluid for cleaning the filter medium; and a fluid supply passage connected to the discharge port of the filtration unit, for discharging the fluid having been washed with the raw water in the filtration unit to the outside of the vessel And a discharge passage.

According to this configuration, since the depth of the depth filter forming the filter medium is 1 to 25 占 퐉, most of the plankton can be captured while being picked up and discharged out of the boat, thereby preventing the marine ecosystem In addition, since there is no need for cavitation or drug administration for treating plankton as in the prior art, the power consumption of the power and the amount of medicine used can be reduced. As a result, it is possible to construct a system that is small and has a low processing cost. Further, since the filter material is backwashed and cleaned, the filtration performance of the filter material can be recovered and used, and the processing cost can be further reduced.

In the ballast water producing apparatus according to the present invention, it is further preferable that the ballast water producing apparatus further comprises an ultraviolet irradiating unit for irradiating the filtered water filtered by the filtration unit with ultraviolet rays. In the case of treating plankton by irradiating ultraviolet rays, when the intensity of ultraviolet rays is lowered due to suspended particles or the like in seawater, it is necessary to increase the number of ultraviolet lamps as a countermeasure thereto, leading to an increase in size of apparatus and increase in power consumption. According to this constitution, as described above, most of the plankton in the seawater is removed beforehand by the depth filter, so that the intensity of the ultraviolet rays is suppressed from being lowered, so that the irradiation amount of ultraviolet rays is reduced. Thereby achieving downsizing of the device and reduction in power consumption.

When the ultraviolet irradiation unit is used, it is preferable that the filter material is a depth filter having a pore diameter of 1 to 10 mu m. Generally, large plankton requires a large amount of ultraviolet energy to be killed, and a large amount of irradiation energy is required to kill planktonic species, as compared with the killing of bacteria. Therefore, it is very important to remove planktonic substances as much as possible before irradiating ultraviolet rays, in order to miniaturize the ultraviolet irradiation unit and to reduce power consumption. In the filtration unit having this structure, it is possible to remove almost all the large plankton of 50 mu m or more, and to remove most of the small plankton of 10 mu m or more. In addition, not only plankton but also suspended particles (SS component) having a size up to about 1 mu m can be removed. As a result, the turbidity in the raw water is greatly lowered, and the transparency remarkably increases. As a result, at the time of irradiating ultraviolet rays, the transmittance of ultraviolet rays is greatly improved and the transmittance of ultraviolet rays is improved, so that the irradiation amount of ultraviolet rays can be reduced, so that miniaturization of unit and reduction of power consumption are achieved. In addition, contamination adhering to the surface of the ultraviolet lamp is remarkably reduced, and the maintenance of the unit can be improved.

In the ballast water producing apparatus according to the present invention, it is preferable to further include a chemical processing unit for inputting the solid calcium hypochlorite into the filtered water filtered by the filtration unit. When chemicals such as chlorine or sodium hypochlorite are added to generate hypochlorous acid to treat plankton, a large amount of medicines are required to kill plankton, and when ballast water is discharged to the ocean, sodium hypochlorite It is necessary to neutralize by the administration of a reducing agent, which results in a high load on the environment and a high treatment cost each time. According to this configuration, since the depth of the depth filter is 1 to 25 占 퐉, most of the plankton can be captured while being picked up and discharged out of the boat, and it is not necessary to administer a large amount of medicament for treating plankton Therefore, the amount of calcium hypochlorite to be used is reduced, and the neutralization process by the reducing agent when returning the ballast water to the seawater becomes unnecessary. As a result, it is possible to construct a system that is small and has a low processing cost.

When the chemical treatment unit is used, the chemical treatment unit may include a container in which solid calcium hypochlorite is contained and a concentrated liquid in which solid sodium hypochlorite extracted from the container is dissolved, into the filtrate, It is preferable that the unit is a unit for treating microorganisms. According to this constitution, since calcium hypochlorite is used, transportation is easy and economical regardless of land and sea, unlike liquid medicines, and restrictions on transportation are relaxed. In addition, since calcium hypochlorite has a high melting point, it is easy to store even in a high temperature line. In addition, since it is solid, the volume is small and the storage place can be small. At the same time, the apparatus itself can be miniaturized, which is advantageous in a case where the space is limited.

Wherein when the chemical processing unit is used, the chemical processing unit dissolves the solid calcium hypochlorite in a part of the filtered water branching off from the water feed passage for feeding the filtered water to join the filtered water in the water feed passage, And throttle means for reducing the flow rate of the filtered water in the water supply passage is preferably formed between the branch point and the confluence point. According to this configuration, since the surplus filtered water is supplied from the branch point to the solid hypochlorous acid by reducing the flow rate, a supply means such as a dedicated pump is not required, which simplifies the construction and reduces power required. Instead of the throttle means, a small-sized small injection pump may be formed, and a part of the filtered water may be taken out from the water supply passage.

When the chemical treatment unit is used, it is preferable that the solid calcium hypochlorite is contained in a closed container. According to this configuration, the odor of chlorine is prevented from leaking into the ship. When the solid calcium hypochlorite is exchanged, the calcium hypochlorite does not directly contact the air in the person or the ship because it can be exchanged for each container.

A method for producing filtered water according to the present invention is a method for producing filtered water by filtering raw water with a depth filter having a pore diameter of 1 to 25 탆 and supplying raw water to the depth filter and supplying a fluid from the filtered water side to the depth filter And discharging the fluid together with the raw water.

According to this configuration, since the filtration performance of the filter material is restored by using the reverse flow cleaning, the maintenance cost can be suppressed. Also, since the raw water is always supplied to the filtration unit during backwashing, it is possible to smoothly drain the backwash fluid without flowing backward to the raw water supply side. Further, unlike the surface filter, which collects the substance to be adsorbed only on the surface of the filter, the depth filter can collect the substance to be entrapped in the entire thickness direction of the filter, so that the amount of trapping is large and the filter is not clogged for a long time.

The method for producing ballast water according to the present invention is a method for producing ballast water using the ballast water producing apparatus of the present invention, wherein, in a state in which the supply of the filtered water from the filter medium to the ballast tank and the supply of the fluid to the filter medium are stopped, The raw water is supplied to the filtration unit while the supply of the raw water from the filter medium and the supply of the fluid to the filter medium are stopped and the filtered water is supplied to the filtrate discharge port And supplying the raw water to the filter medium from the filtration water side while feeding the raw water to the filter medium while feeding the filtration water to the ballast tank is stopped and supplying the fluid to the filter medium from the discharge port through the discharge pathway And discharging it to the outside of the ship.

According to this configuration, the plankton that reproduces in the sea can be returned to the ship without damaging it as much as possible, and it is small and the processing cost can be suppressed to a low level. Since the raw water is always supplied to the filtration unit, it is possible to avoid a sudden pressure fluctuation in the passage, thereby preventing the generation of the water hammer. In addition, since the raw water is supplied to the filtration unit in the backwash process, the backwash fluid can be drained smoothly without flowing back to the raw water supply side.

The present invention will be more clearly understood from the following description of the preferred embodiments with reference to the accompanying drawings. It should be understood, however, that the drawings and drawings are for the purpose of illustration and description only and are not to be construed as limiting the scope of the invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same part numbers in the plural drawings denote the same parts.
1 is a block diagram of a ballast water producing apparatus provided with a filtration unit according to a first embodiment of the present invention.
2 is an enlarged cross-sectional view of the filtration unit.
3 is a driving process chart of the filtration system.
4 is a graph showing the relationship between the supply flow rate of the raw water and the pressure loss when the hole diameter of the depth filter is changed.
5 is a perspective view of a filtration unit according to a second embodiment of the present invention.
6 is a plan view of the fixing plate of the filtration unit according to the second embodiment.
7 is a block diagram of a ballast water producing apparatus according to a third embodiment of the present invention.
Fig. 8 is a flow chart when filtering with one of the filtration units of the ballast water producing apparatus according to the third embodiment. Fig.
Fig. 9 is a flow chart for filtering with the other filtration unit of the ballast water producing apparatus according to the third embodiment. Fig.
10 is a perspective view of a filtration unit according to a fourth embodiment of the present invention.
11 is a block diagram of a ballast water producing apparatus according to a fifth embodiment of the present invention.
12 is a driving process chart of the filtration system according to the fifth embodiment.
13 is a block diagram of a ballast water producing apparatus according to a sixth embodiment of the present invention.
Fig. 14 is a block diagram of a chemical treatment unit in a ballast water producing apparatus according to a seventh embodiment of the present invention. Fig.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of a ballast water producing apparatus for a ship having a filtration unit according to a first embodiment of the present invention; FIG. The ballast water producing apparatus 1 is provided in the ship S and includes a ballast pump 2 for introducing the raw water RW into the ship S and a filtration unit 4 for filtering the raw water RW . The filtration unit 4 is provided with a raw water passage 5 to which raw water RW is supplied by the ballast pump 2 and filtered water FW from the filtration unit 4 to a ballast tank 6 And a discharge passage 14 for discharging the raw water RW in the filtration unit 4 together with the compressed air A to be described later is connected to the water supply passage 8, And a gas supply passage 12 for supplying compressed air (A) to the filtration unit 4 is connected. Thereby, the existing filtration unit is replaced with the filtration unit 4 of the present invention for the conventional ballast water producing apparatus already mounted on the vessel S, and further the gas supply passage 12 is provided in the existing water supply passage The present invention can be easily applied to existing ballast water producing apparatuses.

The passages 5, 8, 12, and 14 are formed by piping. In the filtration unit 4, a depth filter 10, which is a filter medium for forming a filtration membrane in a cylindrical casing 9, is accommodated. In the present embodiment, the ballast pump 2 is mounted on a ship, but it may be formed on the outside of the ship, for example, in a port.

The first automatic opening and closing valve MV1 functioning as a regulating valve for the raw water flow rate is connected to the raw water passage 5 and between the first automatic opening and closing valve MV1 and the filtration unit 4 in the raw water passage 5, In short, the primary pressure sensor P1 is formed on the primary side of the filtration unit 4. The second automatic opening and closing valve MV2 functioning as a water feed valve for filtering water FW is connected to the water feed passage 8 and the second automatic opening and closing valve MV2 and the filtration unit 4 in the water feeding passage 8 are connected, The secondary pressure sensor P2 is formed on the secondary side of the filtration unit 4, in other words. A mixer 26 is formed on the upstream side of the ballast tank 6 in the water supply passage 8. A sterilizing agent and filtrate water FW fed from the chemical tank 28 by the mixer 26 And is stirred. The drugs to be added are, for example, hypochlorous acids and peroxides. In addition, other known germicidal means for producing treatment water meeting the criteria prescribed in the ballast water management treaty may be used in place of the method of injecting the medicine. As a specific example, a method of contacting with ozone, a method of irradiating ultraviolet rays, and the like.

The gas supply passage 12 is connected to a third automatic opening and closing valve MV3 serving as a compressed air introducing valve and the discharging passage 14 is connected to a fourth automatic opening and closing valve MV4 serving as a drain valve. One end of the gas supply passage 12 is connected to an air compressor (not shown), and the other end is connected to a secondary side of the lower portion of the filtration unit 4. The other end of the gas supply passage 12 may be connected to the vicinity of the filtration unit 4 in the water supply passage 8, more specifically, between the filtration unit 4 and the secondary pressure sensor P2. The controller 30 controls the driving of the ballast pump 2 and the first to fourth automatic opening / closing valves MV1 to MV4. The outputs of the primary pressure sensor P1 and the secondary pressure sensor P2 are input to the controller 30. [

The air compressor may be mounted on a ship for another purpose or may be provided exclusively for use. As each of the automatic opening / closing valves MV1 to MV4, an air drive valve, an electrically operated valve, an electromagnetic valve or a manual valve which does not use a controller is used.

The depth filter 10 has a hollow cylindrical shape in which one end is opened and the other end is closed by the closure member 13 and the opening end 10a at one end thereof is directed to the filtrate water outlet port 16, ) Communicates with the filtrate water outlet (16). When the raw water RW passes through the depth filter 10 in the radial direction, foreign matter is trapped by vacancies in the filter to obtain filtered water FW. The depth filter 10 is further provided so as to be freely detachably received in the casing 9 of the filtration unit 4 so that the opening end 10a is lower than the other end disposal end 10b, 4 are arranged so as to be inclined downward toward the filtrate water outlet 16. The inclination angle alpha between the center line C in the longitudinal direction of the depth filter 10 and the horizontal plane H is preferably 20 to 70 degrees and more preferably 30 to 60 degrees.

2, which is an enlarged sectional view of the filtration unit 4, a filtration water outlet 16 is formed in one end wall 9a of the lower side of the casing 9 of the inclined filtration unit 4, and the filtration unit 4 A raw water supply port 18 is formed in a lower portion near the one end wall 9a of the peripheral wall 9b of the casing 9 of the casing 9 and is located above the raw water supply port 18, An outlet 22 is formed in the upper portion near the other end wall 9c of the wall 9b.

The raw water passage 5 is connected to the raw water supply port 18 and the water supply passage 8 is connected to the filtered water discharge port 16 and the discharge passage 14 is connected to the discharge port 22. Since the filtrate discharge port 16 is connected to the filtrate discharge port 16 and the filtrate discharge port 16 also serves as the gas supply port 24 for the compressed air A in the filtration unit 4, The supply port 24 is formed at a position lower than the discharge port 22 which is the outlet of the compressed air A and the raw water RW. Thereby, since the raw water RW is discharged by pushing up the raw water RW in the discharge passage 14 by using the air lift effect by the pressure of the compressed air A, that is, by the air, The air A can be smoothly discharged. The raw water supply port 18 and the discharge port 22 are formed on the primary side of the depth filter 10 and the filtrate discharge port 16 is formed on the secondary side.

The depth filter 10 is an external-pressure-type cylindrical filter and has a vertical cross-sectional shape in a U-shape. The depth filter 10 is, for example, a laminated type in which a synthetic fiber or a chemical fiber is formed into a cylindrical shape by performing a deposition, a molding or the like in the form of a web, a nonwoven fabric, a paper or a fabric. As the synthetic fiber, a heat-meltable polymer such as polyolefin, polyester, nylon or ethylene vinyl alcohol copolymer, or a polymer such as polyvinyl alcohol or polyacrylonitrile can be used. Among them, polyolefins and polyesters, specifically polypropylene, are preferable from the viewpoint of liquid-wicking property at the time of filter replacement when backwashing by gas is carried out. In addition, the filter is preferably structured such that the density and fineness of the fiber are changed in the thickness direction thereof so that the fiber density is low or the degree of fineness is large on the outside of the filter (raw water inflow side). The depth filter 10 may also be called a failure filter which spirally winds filaments or spun yarns, or a resin molding type which is a resin molding such as a sponge.

The pore diameter of the filtration membrane is 1 to 25 탆, more preferably 1 to 10 탆. If the pore diameter is too small, clogging occurs and the pressure loss becomes large. If the pore diameter is too large, small plankton will pass through. Therefore, in order to reduce this, another means such as cavitation is required, which increases the manufacturing cost of the ballast water.

The depth filter 10 can be used in the filtration unit 4 without back pressure, and the filtration performance can be restored by backwashing and the pressure difference during filtration can be increased. In this embodiment, the backwash is performed by compressed air A supplied from a compressor (not shown) through the gas supply passage 12 (Fig. 1), and compressed air A is 0.05 to 0.2 MPa higher than the indicated pressure of the primary pressure sensor P1. The fluid used in the backwash may be a gas other than air, such as nitrogen, or may be liquid such as fresh water or filtered seawater.

Next, an operation method of the ballast water producing apparatus, that is, a filtration water producing method using the filtration unit according to the present embodiment will be described with reference to Figs. 1 and 3. Fig. As shown in Fig. 3, the operation method of the ballast water producing apparatus is composed of an air discharging step, a first converting step, a filtering step, a second converting step, a third converting step and a backwashing step.

When the ballast water producing apparatus 1 is operated by operating a start button (not shown) provided in the controller 30, the ballast pump 2 is first started so that the first automatic opening / closing valve MV1 and the fourth automatic opening / (MV4) to open the air discharge process. In the air discharge step, the second automatic opening / closing valve MV2 and the third automatic opening / closing valve MV3 are closed to supply the filtered water FW from the depth filter 10 to the ballast tank 6 and to the depth filter 10 The raw water RW is discharged to the discharge passage 14 through the filtration unit 4 in the state where the supply of the compressed air A is stopped and the raw water 5 and the air of the filtration unit 4 Discharge.

Next, the second automatic opening / closing valve MV2 is opened to enter the first switching step. The raw water RW is supplied to the discharge passage 14 via the filtration unit 4 and the raw water RW is supplied to the water supply passage 8 through the filtration unit 4 in the state where the supply of the compressed air A to the depth filter 10 is stopped, (FW), respectively.

Subsequently, the fourth automatic on-off valve MV4 is closed to enter the filtration step. In the filtration step, raw water (RW) is supplied to the filtration unit (4) while the supply of compressed air to the depth filter (10) and the depth filter is stopped, (8). At this time, the raw water RW passes through the filtration film of the depth filter 10 from the outside of the depth filter 10 and flows into the hollow portion 11, so that foreign matter in the raw water RW is removed and filtered. The filtered water FW passes through the water supply passage 8 and is supplied to the ballast tank 6.

Next, the fourth automatic opening / closing valve MV4 is opened to enter the second switching step. In the second switching step, the raw water RW is supplied to the filtration unit 4 while the supply of the compressed air A to the depth filter 10 is stopped, whereby the filtered water FW is supplied to the water supply passage 8, And flows the raw water RW into the discharge passage 14. [

Subsequently, the second automatic opening / closing valve MV2 is closed to enter the third switching step. In the third switching step, the supply of the filtered water FW from the depth filter 10 to the ballast tank 6 and the supply of the compressed air A to the depth filter 10 are stopped and the raw water RW is discharged And flows into the passage 14. By stopping the supply of the filtrate water FW from the depth filter 10 in this way, the supply of the compressed air A in the direction opposite to the flow direction of the filtered water FW in the next backwashing process is prepared.

Next, while the second automatic on-off valve MV2 is closed, the third automatic on-off valve MV3 is opened to enter the backwash process. In the backwash process, raw water (RW) is supplied to the filtration unit (4) while the supply of the filtration water (FW) to the ballast tank (6) The compressed air A is supplied to the discharge passage 14 along with the raw water RW. Thereby, the compressed air A passes through the depth filter 10 in the direction opposite to the filtration step, so that the foreign matter adhered to the depth filter 10 and the foreign matter accumulated in the casing 9 are drawn out of the filtration unit 4, And discharges it from the discharge passage 14 to the outside of the vessel S.

When the backwashing process is completed, the third automatic opening / closing valve MV3 is closed to return to the air discharging process. Then, this loop is repeated. The duration time of the air discharge process is variably set by a time limit device such as a timer. The set time varies depending on the scale of the treatment facility, but is, for example, several seconds to one minute. The first, second, and third switching processes are very short times, for example, several seconds, and this can be variably set by a time limit device such as a timer. In this way, by passing through the first, second, and third conversion steps before entering the filtration step and backwashing step, rapid pressure fluctuation in the passage can be avoided. The time of the filtration process and the backwash process varies depending on the water quality of the raw water and the scale of the facility, but is, for example, about 10 minutes, which is variably set by a timekeeping device such as a timer. The transition from the filtration step to the second switching step may be carried out at a time point when the pressure difference? P (= P1 - P2) between the primary pressure sensor P1 and the secondary pressure sensor P2 becomes larger than the specified value .

During the filtration process, the controller 30 always monitors the pressure difference ΔP, and if the pressure difference ΔP exceeds the alarm value H1, an alarm such as a buzzer is issued to urge attention. At this point, the ballast water producing apparatus 1 continues to operate. Further, when the differential pressure AP becomes larger and exceeds the emergency stop value H2, an alarm such as a bell is issued and the ballast water producing apparatus 1 stops urgently. More specifically, the controller 30 stops the ballast pump 2 and all the automatic opening / closing valves MV1 to 4 are closed.

Sudden changes in pressure and velocity change not only damage the plankton but also cause water hammer to occur in the ballast pump 2, each of the automatic opening and closing valves MV1 to 4 and the respective passages 5, 8, 12 and 14 The supply of the raw water RW from the ballast pump 2 is not stopped and the automatic opening and closing valves MV1 to MV4 are closed as in the operation method of Fig. The timing of opening and closing of the valve can be controlled so that a mild operation can be performed. In addition, since backwashing is performed while flowing raw water RW, it is possible to smoothly discharge the air by the discharge pressure of the ballast pump 2 and the air pressure of the compressed air (A), and a separate drain pump and drain piping are unnecessary, Can be simplified.

In the above configuration, since the filtration membrane forming the depth filter 10 has a pore diameter of 1 to 25 占 퐉, most of the plankton can be captured while suppressing the pressure loss due to clogging of the filter, It is possible to reduce the power consumption of the power and the amount of the medicine to be used because it does not destroy the marine ecosystem of the loader and does not require cavitation or medicine administration for treating the plankton as in the past. As a result, it is possible to construct a ballast water producing apparatus having a small size and a low processing cost. Further, since the depth filter 10 is backwashed, the filtration performance of the depth filter 10 can be recovered and used, and the processing cost can be further reduced. Furthermore, since the inexpensive depth filter 10 is used, the initial introduction cost can be suppressed as compared with the case of using a surface filter that captures foreign matter on the surface of a filter such as a flat membrane.

Since the gas supply port 24 and the filtrate discharge port 16 are the same, the gas supply port 24 and the filtrate discharge port 16 can be made common to simplify the structure.

Since the filtration unit 4 is disposed so as to be inclined downward as it faces the filtrate discharge port 16, the side opposite to the filtrate discharge port 16 of the filtration unit 4 becomes high, Air (A) in the filtration unit (4) is easily discharged when raw water (RW) is filtered after cleaning, and there is less possibility that air is mixed into the filtered water (FW). If the inclination angle? With respect to the horizontal direction is too large, the vertical dimension of the filtration unit 4 becomes large. Therefore, in the maintenance such as disassembly, the depth filter 10 for taking out the depth filter 10 above the filtration unit 4 A large space is required, and if it is excessively small, air (A) in the filtration unit 4 is not discharged well. Therefore, it is preferable that the inclination angle alpha is 20 to 70 degrees.

Since the outlet 22 is formed above the raw water supply port 18, the supply of the raw water is restarted at the initial stage of starting the supply of the raw water for the filtration operation or after the backwashing, The air A in the filtration unit 4 is smoothly discharged.

3, the ballast pump 2 is always operated during the operation of the system. In other words, since the raw water RW is always supplied to the filtration unit 4, It is possible to avoid the occurrence of sudden pressure fluctuations in the flow channel, thereby preventing occurrence of water hammer. Since the raw water RW is also supplied to the filtration unit 4 in the backwash process, the compressed air A is supplied to the raw water passages 5 (5) by the supply pressure of the compressed air A and the supply pressure of the raw water RW It is possible to smoothly discharge the water by flowing it in the raw water stream.

Further, unlike the surface filter, which collects the substance to be adsorbed only on the surface of the filter, the depth filter can collect the substance to be entrapped in the entire thickness direction of the filter, so that the filter does not cause clogging for a long time due to a large amount of trapping.

A verification experiment was performed using the depth filter 10 in the present embodiment. The raw water is seawater, and the supply pressure and flow rate of raw water are 0.03 MPa and 0.037 ㎥ / min, respectively. Compressed air is used for the stationary fluid, and the supply pressure and the flow rate of compressed air are 0.13 MPa and 0.4 Nm3 / min, respectively. The depth filter used was 25 cm long and had a hole diameter of 1 탆 and 25 탆. Further, the axis of the depth filter was disposed at an inclination of 45 ° with respect to the horizontal plane.

Verification 1: Initial pressure loss

Table 1 shows the difference in pressure between the primary side and the secondary side of the depth filter when raw water is supplied in a depth filter having a pore diameter of 0.5 mu m, 1 mu m, and 25 mu m when the raw water temperature is 25 DEG C, 4 is a graph showing the relationship between the supply flow rate of the raw water and the pressure loss. As is evident from Table 1 and Fig. 4, the pressure loss was small in the depth filters of 1 mu m and 25 mu m, but in the depth filter of 0.5 mu m, the pressure loss was very large, and almost no raw water flowed. Therefore, it is preferable that the hole diameter of the depth filter is 1 占 퐉 or more.

Hole diameter Pressure loss 0.5 탆 0.03 MPa 1 ㎛ 0.017 MPa 25 탆 0.012 MPa

Verification 2: Backwash effect

Table 2 shows the state of the depth filter (differential pressure state) in the continuous filtration operation and the filtration operation and the backwash operation alternately in the depth filters having the pore diameters of 1 mu m and 25 mu m, respectively. In alternate operation of filtration and backwash, filtration operation and backwash operation were alternately repeated every 5 minutes. When the continuous filtration operation was performed, the differential pressure rises in about 2 hours in the depth filter of 25 mu m and in the pressure filter of 1 mu m in about 40 minutes, and the depth filter is closed. In alternate operation of filtration and backwashing, the differential pressure did not increase even after 5 hours continuous operation in either depth filter of 1 탆 or 25 탆, and the depth filter was not blocked.

Hole diameter Continuous filtration operation Filtration / Reverse operation     1 ㎛ The differential pressure rises for about 40 minutes, No differential pressure rise after 5 hours    25 탆 The differential pressure rises about 2 hours, No differential pressure rise after 5 hours

Verification 3: Water quality of filtered water

Table 3 shows the number of particles (number of particles in the water) contained in raw water and 1 ml of filtered water in each of the depth filters having pore diameters of 1 탆, 10 탆 and 25 탆 and the removal rate. The denominator of each data represents the number of particles in the water in the raw water, the number of particles in the water in the molecule of the filtered water, and the numerical value in the parentheses represents the removal rate. In the depth filter having a pore diameter of 25 탆, about 96% of particles having a particle diameter of 25 탆 or more and about 88% of particles having a particle diameter of 10 탆 or more are removed, and 60% or more of particles having a particle diameter of 1 탆 or more are removed. In the depth filter having a pore diameter of 1 탆, about 99% or more of particles having a particle diameter of 25 탆 or more, about 94% of particles having a particle diameter of 10 탆 or more are removed, and 90% or more of particles having a particle diameter of 1 탆 or more are removed.

Particle diameter Hole diameter: 1 탆 Hole diameter: 25 탆 1 ㎛ or more 1985/20000 or more (90% or more) 7634/20000 or more (61% or more) 10 ㎛ or more 111/1829 (94%) 139/1153 (88%) 25 μm or more 1/249 (99% or more) 4/94 (96%)

Verification 4: Drug dosage

Table 4 shows the concentration of the agent (hypochlorous acid) necessary for disposing the bacteria and microorganisms remaining in the filtered water after passing through the depth filter 10. The "depth" filter 10, which is not subjected to filtration, that is, natural sea water and has a pore diameter of 50 μm, is used for conventional ballast water production. As can be seen from Table 4, when the hole diameter is 30 탆, the effect is smaller than that of the conventional 50 탆. However, when the depth filter 10 of 25 탆 is used, , And in the case of 10 占 퐉, the concentration may be one eighth or less. Therefore, it is preferable that the hole diameter of the depth filter is 25 占 퐉 or less.

Hole diameter (탆) Concentration (ppm) of required agent (hypochlorous acid) Remarks none over 10 Natural seawater 50 8 Conventional 30 5 25 3 10 1 or less

As can be seen from the result of the verification 1, the depth filter 10 used in this embodiment has almost no pressure loss even though the hole diameter is 1 mu m. Therefore, the projection area of the depth filter 10 is small, The size of the unit 4 can be suppressed. Further, as can be seen from the result of the verification 2, it is possible to use repeatedly by backwashing. As a result, the life span remarkably becomes longer. As can be seen from the results of the verification 3, 90% or more of the plankton of 50 占 퐉 or more and 80% or more of the plankton of 10 占 퐉 or more are removed with a pore diameter of 25 占 퐉. As can be seen from the results of Verification 4, the pore diameter is set to 25 占 퐉, which is solved by a drug having a concentration of 1/3 as compared with the case of using a filter having a pore diameter of 50 占 퐉. Therefore, the depth of the depth filter 10 can be 1 to 25 탆.

Fig. 5 is a perspective view showing the filtration unit 4A according to the second embodiment of the present invention, which includes a plurality of depth filters 10. Fig. Like the first embodiment, the filtration unit 4A includes a filter member 38 and a cylindrical casing 9A that accommodates the filter member 38. The casing 9A has a filtrate water outlet 16A and a raw water supply port 18A A discharge port 22A and a gas supply port 24A, and the filtrate discharge port 16A and the gas supply port 24A are common to each other. The arrangement and functions of the filtrate water outlet 16A, the raw water supply port 18A, the discharge port 22A and the gas supply port 24A are the same as those of the first embodiment.

A cover 9Ac is formed on the upper portion of the casing 9A so as to be freely opened and closed, and a bottom plate 9Ad is formed below the casing 9A. A circular through hole 52 is formed in the bottom plate 9Ad at a position corresponding to each depth filter 10 and the hollow portion 11 of each depth filter 10 is connected to the filtrate discharge port 16A and the gas supply port 16A, (24A). In the second embodiment, as the filter material 38, a sub unit in which both ends of a plurality of depth filters 10 are fixed by a fixing plate 40 and is integrated is used. The fastening means is, for example, fastened by an adhesive, but is not limited thereto. Each depth filter 10 is the same as that of the first embodiment except that the depth filter 10 is not closed at one end by the closure member 13 (Fig. 2), that is, it is hollow cylindrical at both ends. In this embodiment, 19 depth filters 10 are used, but the number of depth filters 10 is not limited to this.

6 is a plan view of the fixing plate 40. Fig. The fixed plate 40 is made of, for example, a resin plate, and a circular opening 46 is formed at a position corresponding to each depth filter 10. The diameter of the opening 46 is set to be smaller than the outer diameter of the depth filter 10. In this embodiment, the fixing plate 40 is hexagonal, but may be another polygonal or circular shape. An engaging groove 48 is formed on one side of the fixing plate 40 so as to engage with the engaging plate 44 of the casing 9A to determine the position of the filter member 38 in the circumferential direction with respect to the casing 9A .

Next, a method of assembling the filtration unit 4A of the second embodiment will be described with reference to Fig. First, each depth filter 10 is fixed to the fixing plate 40 so that the both ends of the depth filter 10 coincide with the opening 46 using an adhesive or the like, thereby completing the filter member 38 as a sub unit .

Subsequently, the filter member 38 is inserted into the casing 9A in a state in which the engageable groove 48 of the fixing plate 40 shown in Fig. 5 is engaged with the engaging plate 44 of the casing 9A. Further, by closing the lid 9Ac, the filter material 38 is held between the lid 9Ac and the bottom plate 9Ad and is strongly supported.

Since the upper part of the depth filter 10 is abolished by the lid part 9Ac, the filtered water FW in the hollow part 11 of the depth filter 10 passes through the through hole 9Ad of the lower bottom plate 9Ad, (52) and is drawn out from the filtered water outlet (16A). The backwashing compressed air A introduced into the filtration unit 4A from the gas supply port 24A flows from the through hole 52 of the bottom plate 9Ad into the hollow portion 11 of the depth filter 10, And the depth filter 10 is cleaned.

According to the second embodiment, the same effects as those of the first embodiment can be obtained, and since the plurality of depth filters 10 are combined to form the filter material 38, the filtration area is increased, . Further, since the plurality of depth filters 10 are integrated as a subunit, the plurality of depth filters 10 can be easily exchanged by exchanging the integrated filter medium 38. [

7 is a schematic diagram of a ballast water producing apparatus according to a third embodiment. 1 is different from the embodiment of FIG. 1 in that it has two first and second filtration units 4B and 4C, and while it is being filtered by one of the filtration units 4B and 4C, the other filtration unit 4C ) 4B is countercurrently cleaned, and the other structure and operation are the same as those of the apparatus of Fig. The filtration units 4B and 4C may be the filtration unit 4 of the first embodiment or the filtration unit 4A of the second embodiment.

The raw water passage 5 to which the raw water RW is supplied from the ballast pump 2 is branched into the two raw water branch passages 5B and 5C so that the first and second raw water branch passages 5B, 5C are connected to the raw water supply ports 18B, 18C of the first and second filtration units 4B, 4C, respectively. First and second raw water inlet valves B1 and C1 are formed in the first and second raw water branch passages 5B and 5C, respectively. The water feed passage 8 for feeding the filtered water FW to the ballast tank 6 via the mixer 26 and the chemical tank 28 is also branched into two first and second filtered water branch passages 8B and 8C And the first and second filtrate branch passages 8B and 8C are connected to the filtrate discharge ports 16B and 16C of the first and second filtration units 4B and 4C, respectively. First and second filtered water supply valves B2 and C2 are formed in the first and second filtered water branch passages 8B and 8C, respectively.

The air supply passage 12 for supplying the backwashing compressed air A is also branched into the first and second air branch passages 12B and 12C and the first and second air branch passages 12B and 12C, Are respectively connected to the upstream side of the first and second filtered water supply / discharge valves B2 and C2 in the first and second filtered water branch passages 8B and 8C, that is, the filtration units 4B and 4C. First and second air supply valves B3 and C3 are formed in the first and second air branch passages 12B and 12C, respectively. The discharge passage 14 for discharging the raw water RW in each of the filtration units 4B and 4C along with the compressed air A is also branched into two first and second discharge branch passages 14B and 14C, And the second drainage branch passages 14B and 14C are connected to the outlets 22B and 22C of the first and second filtration units 4B and 4C, respectively. First and second discharge valves B4 and C4 are formed in the first and second branch branch passages 14B and 14C, respectively.

In this embodiment, the ballast pump 2, the ballast tank 6, the mixer 26, the chemical tank 28 and the raw water passage 5, the water supply passage 8, the air supply passage 12, 14 can use an existing one for the vessel, and only the filtration units 4B, 4C according to the present embodiment and each branch pipe connected thereto can be replaced with existing ones. As the valves B1 to 4 and C1 to C4, an air drive valve, an electrically operated valve, a manual valve which does not use a solenoid valve or a controller, and the like are used.

Next, a method of operating the ballast water producing apparatus of the present embodiment will be described with reference to Figs. 8 and 9. Fig. Fig. 8 is a flow chart when filtration is performed with the first filtration unit 4B and the second filtration unit 4C is countercurrently cleaned. At this time, the first raw water inflow valve B1, the first filtered water supply and discharge valve B2, the second raw water inflow valve C1, the second air supply valve C3 and the second discharge valve C4 are opened, The first air supply valve B3, the first discharge valve B4 and the second filtered water supply valve C2 are closed. The raw water RW supplied by the ballast pump 2 passes through the first and second raw water branch passages 5B and 5C and is supplied to the first and second filtration units 4B and 4C. The raw water RW supplied to the first filtration unit 4B is filtered by the depth filter 10 and is sent to the ballast tank 6 from the first supply and reception branch passage 8B through the water supply passage 8 . On the other hand, the compressed air A supplied from the air compressor (not shown) passes through the second air branch passage 12C and is supplied to the second filtration unit 4C to back-flow the depth filter 10, Is discharged from the second discharge branch passage 14C together with the raw water RW through the discharge passage 14 and out of the ship. Arrows RA and RA indicate the flow of the raw water RW, the filtered water FW and the compressed air A, respectively.

FIG. 9 is a flow chart when filtration is performed with the second filtration unit 4C and the first filtration unit 4B is countercurrently cleaned. At this time, the first raw water inflow valve B1, the first air supply valve B3, the first discharge valve B4, the second raw water inflow valve C1 and the second filtered water supply valve C2 are opened, The first filtered water supply / discharge valve B2, the second air supply valve C3 and the second discharge valve C4 are closed. The raw water RW supplied by the ballast pump 2 passes through the first and second raw water branch passages 5A and 5B and is supplied to the first and second filtration units 4B and 4C. The raw water RW supplied to the second filtration unit 4C is filtered by the depth filter 10 and is sent from the second supply and reception branch passage 8C through the water supply passage 8 to the ballast tank 6 . On the other hand, the compressed air A supplied from the air compressor (not shown) passes through the first air branch passage 12B and is supplied to the first filtration unit 4B to back-flow the depth filter 10, Is discharged from the first discharge branch passage 14B together with the raw water RW through the discharge passage 14 and out of the ship.

By alternately repeating the opening and closing states of the valves B1 to 4 and C1 to 4 of Figs. 8 and 9 by a timer such as a timer, even if one of the filtration units 4B and 4C is backwashing , And filtration can be performed with the other filtration units 4C and 4B. In the present embodiment, two filtration units 4B and 4C are formed, but three or more filtration units may be used.

According to the third embodiment, since the cleaning and filtration of the first and second filtration units 4B and 4C are simultaneously performed, the filtration can be continued at all times, and the ballast water production time can be shortened. Even if an abnormality occurs in one of the filtration units 4B and 4C, the filtration unit 4C and the other filtration unit 4B can be alternately filtered and countercurrently cleaned, The reliability of the entire system is improved.

Fig. 10 shows the filtration unit 4D of the fourth embodiment. In this embodiment, the cylindrical casing 9D of the inclined filtration unit 4D has a lower one end wall 9Da, a peripheral wall 9Db, and an upper other end wall 9Dc, (C) is inclined and inclined upward from the wall 9Da toward the other end wall 9Dc. The inclination angle alpha between the center line C in the longitudinal direction of the depth filter 10 and the horizontal plane H is preferably 20 to 70 degrees and more preferably 30 to 60 degrees. When the inclination angle alpha is excessively large, the vertical dimension of the filtration unit 4D becomes large, so that a large space is required for extracting the depth filter 10D above the filtration unit 4D at the time of maintenance such as disassembly, , The air (A) in the casing (9D) is not discharged well.

The discharge port 22D connected to the discharge passage 14 in the one end wall 9Da of the casing 9D is connected to the raw water passage 5 in the vicinity of the one end wall 9Da of the peripheral wall 9Db, The sphere 18D includes a gas supply port 24D connected to the gas supply passage 12 near the other end wall 9Dc of the peripheral wall 9Db and a filtered water discharge port 16D connected to the water supply passage 8, Respectively. The filtrate outlet 16 is arranged at the uppermost position in the circumferential direction of the inclined peripheral wall 9b.

An annular bottom plate 9Dd is formed below the gas supply port 24D and the filtered water outlet port 16D in the peripheral wall 9Db of the casing 9D in the axial direction and an opening of the depth filter 10D And the leading end 10Da is supported by the bottom plate 9Dd. In other words, a space S is formed between the other end wall 9Dc and the bottom plate 9Dd of the casing 9D, and the gas supply port 24D, the filtered water outlet port 16D, The opening 10Da of the filter 10D faces the hollow portion 11D of the depth filter 10D and the space S is communicated with each other. The depth filter 10D concentric with the casing 9D is also inclined so that the opening end 10Da is disposed above the closing end 10Db. The other structures are the same as those of the first embodiment.

According to the fourth embodiment, since the opening end 10Da of the depth filter 10D is opened upward in the inclination direction, the vicinity of the closing end 10Db of the depth filter 10D when switching to the air discharging process in the backwashing process The air in the depth filter 10D is prevented from remaining in the depth filter 10D and the filtration can be performed efficiently using the entire depth filter 10D in the filtration process.

In the fourth embodiment, a plurality of depth filters 10D may be provided as in the second embodiment, or a device in which two filtration units 4D are provided as in the third embodiment, It may be combined.

11 is a schematic block diagram of a ballast water producing apparatus according to a fifth embodiment of the present invention. Unlike the ballast water producing apparatus 1 of FIG. 1, the ballast water producing apparatus 1A of the present embodiment is provided with an ultraviolet irradiating unit 3 for irradiating ultraviolet rays to the filtered water FW. The filtration unit 4D of the fourth embodiment shown in Fig. 10 is used as the filtration unit 4 and the filtration water outlet 16 through which the water supply passage 8 is connected to the filtration unit 4 is provided with a discharge passage 14 are connected to the air discharge passageway 19 which is connected to the air discharge passage 19. A fifth automatic opening / closing valve MV5 serving as an air discharging valve is connected to the air discharging passage 19, and the driving of the fifth automatic opening / closing valve MV5 is controlled by the controller 30. [ As the fifth automatic opening / closing valve MV5, there are used an air drive valve, a motor valve, a manual valve which does not use a solenoid valve or a controller, and the like. The rest of the configuration is the same as that of the ballast water producing apparatus 1 of Fig.

The ultraviolet irradiation unit 3 is formed on the upstream side of the ballast tank 6 in the water supply passage 8. The ultraviolet irradiation unit 3 irradiates ultraviolet rays to the plankton and fungi remaining in the filtered water FW filtered by the filtration unit 4 and is irradiated with the ultraviolet rays emitted from the unit case 36 ). The unit case 36 has a cylindrical shape and has an inlet port 29 for the filtered water FW near one end of the peripheral wall and an outlet port 31 near the other end. Each ultraviolet lamp 34 is covered with a protective tube (not shown) such as quartz glass. The filtered water FW that has entered the unit case 36 from the inlet 29 passes through the passage between the ultraviolet lamps 34 and the remaining plankton and fungus are processed to flow from the outlet 31 to the water supply passage 8 ).

Next, the operation method of the ballast water producing apparatus of the fifth embodiment, that is, the filtration water producing method by the filtration unit according to the present embodiment and the processing method by the ultraviolet irradiating unit 3 Will be described. As shown in Fig. 12, the operation method of the ballast water producing apparatus of the fifth embodiment is similar to that of the embodiment of Fig. 1 except that the air discharge step, the first switching step, the filtration step, And a third conversion and backwash process.

When the ballast water producing apparatus 1A is operated by operating a start button (not shown) provided on the controller 30, the ballast pump 2 is first started so that the first automatic opening / closing valve MV1 and the fifth automatic opening / (MV5) to open the air discharge process. In the air discharging step, the second automatic opening / closing valve MV2, the third automatic opening / closing valve MV3 and the fourth automatic opening / closing valve MV4 are closed to remove the filtered water FW from the depth filter 10 to the ballast tank 6, The air is discharged from the filtrate discharge port 16 of the filtration unit 4 through the air discharge passage 19 to the discharge passage 14 in a state in which supply of the compressed air A to the depth filter 10 is stopped, FW) to be discharged from the boat, thereby discharging air from the raw water passage 5 and the filtration unit 4. Since the filtrate discharge port 16 is located near the uppermost portion of the filtration unit 4, the air in the filtration unit 4 is smoothly discharged from the filtrate discharge port 16 to the air discharge passage 19.

Next, the second automatic opening / closing valve MV2 is opened to enter the first switching step. In the first switching step, filtered water (FW) is supplied to the discharge passage (14) and the water supply passage (8) via the filtration unit (4) while the supply of the compressed air to the depth filter (10) Respectively.

Subsequently, the fifth automatic on-off valve MV5 is closed to enter the filtration step. In the filtration step, raw water (RW) is supplied to the filtration unit (4) while the supply of compressed air to the depth filter (10) and the depth filter is stopped, (8). At this time, the raw water RW passes through the filtration film of the depth filter 10 from the outside of the depth filter 10 and flows into the hollow portion 11, so that foreign matter in the raw water RW is removed and filtered. The filtered water FW passes through the inlet 29 and is supplied to the ultraviolet irradiation unit 3.

In the ultraviolet irradiation unit 3, the filtered water FW entered into the unit case 36 is irradiated with ultraviolet rays by the ultraviolet lamp 34 when passing through the unit case 36, so that plankton, And then supplied to the ballast tank 6.

Next, the fourth automatic opening / closing valve MV4 is opened to enter the second switching step. In the second switching step, the raw water RW is supplied to the filtration unit 4 while the supply of the compressed air A to the depth filter 10 is stopped, whereby the filtered water FW is supplied to the water supply passage 8, And flows the raw water RW into the discharge passage 14. [

Subsequently, the second automatic opening / closing valve MV2 is closed to enter the third switching step. In the third switching step, the supply of the filtered water FW from the depth filter 10 to the ballast tank 6 and the supply of the compressed air A to the depth filter 10 are stopped and the raw water RW is discharged And flows into the passage 14. By stopping the supply of the filtrate water FW from the depth filter 10 in this way, the supply of the compressed air A in the direction opposite to the flow direction of the filtered water FW in the next backwashing process is prepared.

Next, while the second automatic on-off valve MV2 is closed, the third automatic on-off valve MV3 is opened to enter the backwash process. In the backwash process, raw water (RW) is supplied to the filtration unit (4) while the supply of the filtration water (FW) to the ballast tank (6) The compressed air A is supplied to the discharge passage 14 along with the raw water RW. Thereby, the compressed air A passes through the depth filter 10 in the direction opposite to the filtration step, so that the foreign matter adhered to the depth filter 10 and the foreign matter accumulated in the casing 9 are drawn out of the filtration unit 4, And discharges it from the discharge passage 14 to the outside of the vessel S. When the backwashing process is completed, the third automatic opening / closing valve MV3 and the fourth automatic opening / closing valve MV4 are closed, and the fifth automatic opening / closing valve MV5 is opened to return to the air discharging process. Then, this loop is repeated.

According to the fifth embodiment, the same effects as those of the ballast water producing apparatus 1 of FIG. 1 are exhibited. Since most of the plankton in the seawater is previously removed by the depth filter 10, the intensity of the ultraviolet rays is prevented from being lowered. Therefore, the number of the ultraviolet lamps 34 is reduced, A reduction in power is achieved.

If the pore diameter of the filtration membrane is 1 to 10 탆, not only the plankton but also the suspended particles (SS component) of the size up to about 1 탆 are removed, so turbidity in the raw water RW is significantly lowered, do. As a result, when the ultraviolet light is irradiated, the transmittance of the ultraviolet light in the raw water (RW) is greatly improved and the transmittance of the ultraviolet light is improved. As a result, The miniaturization of the ultraviolet irradiating unit 3 and the reduction in power consumption are achieved. Although some wipers are formed on the protective pipe in order to prevent contamination of the protective tube and absorption of ultraviolet rays due to contamination, the contamination adhering to the surface of the ultraviolet lamp 34 is remarkably reduced in the present embodiment. It is possible to further suppress the power consumption and to improve the maintenance property of the ultraviolet irradiating unit 3. [

In addition, since the opening end 10a of the depth filter 10 is opened upward, the air in the vicinity of the closing end 10b of the depth filter 10, when switching to the air discharging process in the backwashing process, Air is prevented from remaining in the depth filter 10 and the filtration can be efficiently performed using the entire depth filter 10 in the filtration process. If the inclination angle alpha with respect to the horizontal direction is excessively large, the vertical dimension of the filtration unit 4 becomes large. Therefore, a large space for extracting the depth filter 10 above the filtration unit 4 at the time of maintenance such as disassembly The air A in the vicinity of the closed end 10b in the filtration unit 4 is not discharged well. Therefore, it is preferable that the inclination angle alpha is 20 to 70 degrees.

Example

Examples 1 to 6, Comparative Example 1

A verification experiment was performed using the depth filter 10 in the present embodiment. The depth filter used was a hollow cylindrical shape having a length of 250 mm, an outer diameter of 60 mm and an inner diameter of 30 mm and a hole diameter of 1 탆 (Example 1), 3 탆 (Example 2), 5 탆 (Example 3) (Example 4), 15 占 퐉 (Example 5), 25 占 퐉 (Example 6), and 30 占 퐉 (Comparative Example 1), and the axial center of the depth filter 10 was inclined at 45 ° with respect to the horizontal plane. Turbidity change (5.5 h NTU of raw sea water turbidity) was measured when natural seawater (water temperature 26 ° C) was filtered as raw water at a flow rate of 25 l / min. The measurement results are shown in Table 5. As the pore diameter increases, the differential pressure decreases. However, when the pore diameter exceeds 25 m, the turbidity of the treated water increases, which is not practical.

Subsequently, particles of 10 mu m or more existing in the raw water and in the filtrate of Examples 1 to 6 and Comparative Example 1 were measured with particle counters, respectively, and the removal ratios were determined. The filtered water was placed in a quartz cell having an optical path length of 30 mm, irradiated with ultraviolet rays (20 W lamp), and the ultraviolet illuminance (wavelength 254 nm) transmitted through the quartz cell was measured with a UV intensity meter. The results are shown in Table 6. From Table 2, it can be seen that the ultraviolet transmittance is improved as the suspended particles are removed.

Sea water (water temperature 25 ° C) containing 3.0 × 10 ² zooplankton (the smallest portion of 50 μm or more) per liter and 1.5 × 10 ⁴ phytoplankton per square centimeter (size 8-12 μm) The depth filter of Examples 1 to 6 and Comparative Example 1 in Table 5 and the depth filter having a pore diameter of 50 占 퐉 (Comparative Example 2) were filtered at a flow rate of 25 l / min to measure the number of plankton present in the filtrate. The results are shown in Table 7. In Examples 1 to 6, almost all of the zooplankton was removed, but the zooplankton remained at 20% or more in Comparative Example 1 and about 40% in Comparative Example 2, respectively. In the case of phytoplankton, it was almost removed in Examples 1 and 2, 99% or more in Example 3, about 99% in Example 4, 96% or more in Example 5, 92% of them were removed. In contrast, 60% or more of Comparative Example 1 and 90% or more of Comparative Example 2 remained respectively.

In the case where phytoplankton was observed in the filtered water at a rate of 100 / cc or more, the filtered water was placed in a quartz cell having an optical path length of 10 mm and irradiated with an ultraviolet lamp (20 W). The survival counts of animal and phytoplankton were each irradiated with ultraviolet light until the survival number of each of the animal and phytoplankton was one hundredth or less of the filtered water, and the irradiated ultraviolet dose was also shown in Table 7. In Comparative Examples 1 and 2, since a considerable amount of zooplankton remained in the filtered water, ultraviolet energy of more than 5 times in Example 6 and more than 6 times in Comparative Example 2 was required in Comparative Example 1 to reduce the number of plankton.

Example 7, Comparative Example 3

The continuous filtration test was carried out at a flow rate of 25 l / min using natural water (temperature 26 ° C) using a depth filter (outer diameter 60 mm, inner diameter 30 mm, length 250 mm) having a pore diameter of 3 μm. At this time, comparison was made between the cases where the filtration was carried out continuously (Comparative Example 3) and the cases where the air was backwashed (air pressure 100 ㎪, 5 seconds) for every 3 minutes of filtration (Example 7). The results are shown in Table 8. When the filtration was carried out continuously, the filter was closed and the differential pressure suddenly rises at 30 minutes, so that almost no seawater flows thereafter. However, when the air was backwashed, the pressure difference was stable even after 600 minutes.

13 is a schematic block diagram of a ballast water producing apparatus according to a sixth embodiment of the present invention. The ballast water producing apparatus 1B of the sixth embodiment is different from the ballast water producing apparatus 1B of the first embodiment in that a chemical processing unit 33 for inputting calcium hypochlorite into the filtered water FW is provided instead of the ultraviolet irradiating unit 3 of FIG. 11, except for the configuration and the operation method, are the same as those of the fifth embodiment.

The chemical treatment unit 33 is formed on the upstream side of the ballast tank 6 in the water supply passage 8. The chemical processing unit 33 has a container 35 in which solid hypochlorous calcium is contained by treating the plankton or fungus remaining in the filtered water FW filtered by the filtration unit 4 with calcium hypochlorite .

The container 35 is an enclosed container containing solid hypochlorous acid calcium. The chemical processing unit 33 further includes a branch passage 15 for branching a portion of the filtered water FW from the branch point 8a of the water supply passage 8 and supplying the filtered water FW to the container 35, And a confluent passage 17 for joining the concentrate obtained by dissolving the solid hypochlorous acid solution in the water feed passage 35 to the confluence point 8b downstream of the branch point 8a in the water feed passage 8. Part of the filtered water FW passes through the branch passage 15 and enters the container 35 and gradually dissolves the solid sodium hypochlorite while passing between the granular solid hypochlorite stored in the container 35, A high concentration of hypochlorous acid solution is obtained. Thereby, for example, a calcium hypochlorite concentrate with a concentration of 90% with respect to the saturated concentration is obtained, which passes through the confluent passage 17 and merges with the filtered water FW in the water supply passage 8. The combined filtrate (FW) and the hypochlorous acid concentrate are stirred and homogenized by the mixer 39 formed in the water feed passage 8 to treat the plankton, fungus and the like remaining in the filtrate FW.

A throttle means 25 such as an orifice is formed between the branch point 8a and the confluence point 8b to reduce the flow rate of the filtered water FW passing through the water feed passage 8. Since the throttle means 25 reduces the passage area to a small value, the pressure at the inlet of the throttle means 25 becomes higher than the pressure at the outlet. The pressure difference is preferably about 1 to 10.. A part of the filtered water FW at the branch point 8a on the side of the high pressure side flows into the branch passage 15 and flows through the container 35 and the merging passage 17 to the junction (8b). Therefore, a pump for supplying the filtered water FW from the water supply passage 8 to the container 35 is unnecessary.

A sixth automatic regulating valve MV6 for regulating the flow rate of the concentrated liquid is formed in the confluent passage 17 and a residual chlorine concentration in the filtered water FW is measured on the downstream side of the mixer 39 in the water feed passage 8 And the flow rate of the concentrated liquid is adjusted by the sixth automatic regulating valve MV6 so that the residual chlorine concentration in the filtered water FW is controlled to be a set value. The sixth automatic opening / closing valve MV6 is controlled by the controller 30 and the sixth automatic opening / closing valve MV6 is controlled by an air valve, an electrically operated valve, a manual valve which does not use a solenoid valve or a controller Is used.

The sixth embodiment also has the same effect as the ballast water producing apparatus 1 of Fig. In addition, by capturing most of the plankton in vivo, there is no need to administer a large amount of medicament to treat plankton as in the prior art, so that the amount of medication used can be reduced and the amount of reducing agent A neutralization step by means of the above-described method is also unnecessary. As a result, it is possible to construct a ballast water producing apparatus having a small size and a low processing cost.

In addition, since the chemical processing unit 33 uses solid sodium hypochlorite, transportation is easy, unlike a liquid medicine. In addition, since calcium hypochlorite has a high melting point, it is easy to store even in a high temperature line.

The throttle means 25 for reducing the flow rate of the filtered water FW is formed between the branch point 8a and the confluence point 8b of the water supply passage 8 to reduce the flow rate of the filtered water FW, Is supplied from the branch point 8a to the container 35 containing solid hypochlorous acid calcium, no supply means such as a dedicated pump is required, which simplifies the construction and reduces the power required.

Further, since the solid calcium hypochlorite is contained in the closed container 35, the odor of chlorine is suppressed from leaking into the ship. In addition, when the solid calcium hypochlorite is exchanged, the calcium hypochlorite does not directly come into contact with air in the person or the ship because it can be exchanged every vessel 35.

14 is a systematic view of the chemical processing unit 33A in the ballast water producing apparatus according to the seventh embodiment. The seventh embodiment is obtained by replacing the chemical processing unit 33 of the sixth embodiment with the chemical processing unit 33A, and the other structures are the same as those of the sixth embodiment. In the sixth embodiment, the total amount of the granular solid hypochlorous acid to be used is dissolved at one time. In the chemical treatment unit 33A in the figure, most of the granular solid sodium hypochlorite is the hopper 50, and a part thereof properly metered by the metering tube 51 is dissolved in the dissolving tank 53. As shown in Fig. In this embodiment, the measuring pipe 51 has a weight sensor (not shown), so that it is possible to detect that the granular solid hypochlorous calcium reaches a desired weight. The configuration of the metering tube 51 is not limited to this, and it may be, for example, to detect that a predetermined volume has been reached. The lower part of the hopper 50 and the lower part of the metering pipe 51 are connected via the first valve 54 and the metering pipe 51 and the lower part of the molten bath 53 are connected via the second valve 55 Respectively.

In the seventh embodiment, a large amount (for example, 1000 g) of granular solid hypochlorous acid calcium is charged into the hopper 50, the first valve 54 is opened at any timing, Granular solid calcium hypochlorite is introduced. (For example, 45 g) of granular solid hypochlorous acid is measured by the metering tube 51. After the first valve 54 is closed, the second valve 55 is opened and a necessary amount Of granular solid sodium hypochlorite is introduced. After the introduction, the second valve 55 is closed. The filtration water FW flows into the dissolution tank 53 through the branch passage 15 branched from the water supply passage 8 and agitated by the agitator 56 formed in the dissolution tank 53 to produce granular solid sodium hypochlorite Calcium hypochlorite having a high concentration (for example, 3000 mg / L) is prepared by dissolving in the filtrate FW and joined to the water feed passage 8 via the confluent passage 17 and then stirred with the mixer 39 For example, a treated water having an effective chlorine concentration of 1 mg / l is prepared. The timing at which the granular solid sodium hypochlorite is introduced, that is, the timing at which the first valve 54 is opened, is determined by the numerical value of the residual chlorine meter (M) in the present embodiment. Other means may be used.

According to the seventh embodiment, since the same effect as that of the sixth embodiment is exhibited and only a required amount of the high-concentration calcium hypochlorite solution is produced, the high-concentration calcium hypochlorite solution does not stay in the dissolution tank 53 for a long time, The corrosion of the melting tank 53 is reduced. In addition, since the hopper 50 is formed in the complete dry space, it is easy to replenish the granular solid hypochlorite.

Examples 8 to 12 and Comparative Examples 4 to 5

A verification experiment was performed using the depth filter 10 in the present embodiment. The depth filter used was a hollow cylindrical shape having a length of 250 mm, an outer diameter of 60 mm and an inner diameter of 30 mm and a hole diameter of 1 탆 (Example 8), 3 탆 (Example 9), 10 탆 (Example 10) (Example 11), 25 占 퐉 (Example 12), 30 占 퐉 (Comparative Example 4) and 50 占 퐉 (Comparative Example 5), and the axial center of the depth filter was inclined at 45 ° with respect to the horizontal plane. Sea water (water temperature 25 ° C.) containing 3.0 × 10 ² zooplankton (the smallest portion of 50 μm or more) and 1.5 × 10 ⁴ phytoplankton per square centimeter (size 8 to 12 μm) per liter of raw water, Was filtered at a flow rate of 25 L / min to measure the number of plankton present in the filtrate. The results are shown in Table 9.

In Examples 8 to 12, almost all of the zooplankton was removed, but the zooplankton remained in 20% or more in Comparative Example 4 and 40% in Comparative Example 5. In addition, 99% or more of the phytoplankton was removed in Example 8, 99% or more in Example 9, 96% or more in Example 11, and about 92% in Example 12, Respectively. In contrast, in Comparative Example 4, at least 60% remained, while in Comparative Example 5, at least 90% remained.

Subsequently, a concentrated liquid in which a predetermined amount of granular calcium hypochlorite was added to 1000 L of seawater was prepared. The concentrate was added to the depths of Examples 8 to 12 and Comparative Examples 4 to 5 in Table 9 so as to obtain the effective chlorine concentration shown in Table 10 Was added to the filtered water filtered by a filter. The effective chlorine concentration was measured by a spectrophotometer (UV-1700, manufactured by Shimadzu) after color development using DPD reagent. The water treated with calcium hypochlorite was measured by counting the number of plankton surviving by microscopic observation and then cultured in XM-G medium at 25 DEG C for 7 days to measure the number of E. coli. Further, using Marine Agar medium, , And the number of heterotrophic bacteria was measured. The results are shown in Table 10.

In Examples 8 to 10, no E. coli and heterotrophic bacteria were detected even when the effective chlorine concentration was 1 mg / L. In Examples 11 and 12, no E. coli was detected at 1 mg / L and no heterotrophic bacteria were detected at 2 mg / L. On the other hand, in Comparative Examples 4 and 5, since a considerable amount of zooplankton remained in the filtered water, it is necessary to set the effective chlorine concentration to 5 mg / l in order to reduce the number of plankton, and in order to completely kill bacteria It was necessary to set the chlorine concentrations to 2 mg / L and 5 mg / L, respectively. As described above, in Comparative Examples 4 and 5, hypochlorous acid was required to be at least 5 times as high as those of Examples 8 to 10 and twice as high as Examples 11 and 12. From the above, the hole diameter of the depth filter is preferably 1 to 25 mu m, more preferably 1 to 10 mu m.

While the preferred embodiments of the present invention have been described with reference to the drawings, various additions, modifications, and deletions may be made without departing from the scope of the present invention. For example, in the fifth embodiment shown in Fig. 11 and the sixth embodiment shown in Fig. 13, an ultraviolet irradiation unit 3 and a chemical treatment unit 33 are formed between the filtration unit 4 and the ballast tank 6 The ultraviolet ray irradiation unit 3 and the chemical treatment unit 33 may be formed on the drainage side of the ballast tank 6, that is, on the way from the ballast tank 6 to the outside. When the ultraviolet ray irradiating unit 3 is formed at this position, fungi in the filtered water FW are reduced while being stored in the ballast tank 6, so that irradiation with ultraviolet rays is further suppressed, Power can be reduced. When the chemical processing unit 33 is formed at this position, the liquid containing hypochlorous acid does not flow into the ballast tank 6, and corrosion of the ballast tank 6 can be suppressed. Accordingly, such are also included within the scope of the present invention.

1: Ballast water production system (filtration system)
4: Filtration unit
6: Ballast tank
8: water channel
9: Casing
10: Depth filter (filter medium)
12: gas supply passage
14:
16: Filtrate outlet
18: The raw water supply port
22: Outlet
24: gas supply port
38: Filter media
A: Compressed air
FW: Filtrate
RW: enemies

Claims (15)

A filtration unit comprising a filter medium and a casing for containing the filter medium,
Wherein the casing has a raw water supply port for supplying raw water to the filter medium, a blowout port for the filtration water, a fluid supply port for supplying the cleaning fluid to the filter medium, a fluid backwashing the filter medium and a discharge port for discharging the raw water,
Wherein the water supply port of the filtration water is formed in a lower end wall of the casing and the raw water supply port is formed in a lower portion of one end wall of the peripheral wall of the casing, The discharge port is formed at an upper portion of the other end wall in the discharge port,
The fluid supply port and the filtrate discharge port are the same,
Wherein the filter medium is a depth filter having a pore diameter of 1 to 25 mu m,
Wherein the filter medium has a hollow cylindrical shape with one end opened and the other end closed, and an opening end of the filter medium communicating with the outlet of the filtration water. delete The method according to claim 1,
Wherein the filter medium is integrally formed by fixing both ends of a plurality of depth filters to a fixed plate. The method according to claim 1,
Wherein the filter medium is disposed so as to be inclined downwardly inclined toward the filtered water outlet, the inclined angle being 20 to 70 ° with respect to the horizontal direction. delete delete An apparatus for supplying filtered water taken out from the filtration unit to a ballast tank of a ship as ballast water, comprising: the filtration unit according to claim 1,
A fluid supply passage connected to the fluid supply port of the filtration unit and supplying fluid for cleaning the filter medium,
And a discharge passage connected to the discharge port of the filtration unit for discharging the fluid, which has been washed with the filter material, to the outside of the ship together with raw water in the filtration unit,
And a ballast water supply device. 8. The method of claim 7,
Further comprising an ultraviolet irradiation unit for irradiating ultraviolet rays to the filtered water filtered by the filtration unit. 9. The method of claim 8,
Wherein the filter medium is a depth filter having a pore diameter of 1 to 10 mu m. 8. The method of claim 7,
Further comprising a chemical processing unit for inputting the solid calcium hypochlorite into the filtered water filtered by the filtration unit. 11. The method of claim 10,
Wherein the chemical treatment unit is a unit that includes a vessel containing solid hypochlorous acid calcium and a concentrate obtained by dissolving the solid hypochlorous acid extracted from the vessel into the filtration water to produce a ballast water which is a unit for treating microorganisms with hypochlorous acid generated Manufacturing apparatus. 11. The method of claim 10,
Wherein the chemical processing unit dissolves the solid calcium hypochlorite in a part of the filtered water branching off from the water feed passage for supplying the filtered water to join the filtered water in the water feed passage,
And throttle means for reducing the flow rate of the filtered water in the water supply passage is formed between the branch point and the confluence point. 11. The method of claim 10,
Wherein the solid calcium hypochlorite is contained in a sealed container. A method for producing filtered water by filtering raw water through a depth filter having a pore diameter of 1 to 25 占 퐉,
And a backwash process of supplying raw water to the depth filter while supplying the fluid to the depth filter from the filtration water side and discharging the fluid together with the raw water,
A feed port for the filtered water is formed in a lower end wall of the inclined casing for receiving the depth filter, a feed port for the raw water is formed in a lower portion of one end wall of the peripheral wall of the casing, And a discharge port of the raw water is formed in the upper part of the other end wall of the peripheral wall of the casing,
The fluid supply port and the filtrate discharge port are the same,
Wherein the filter medium is in the form of a hollow cylinder whose one end is open and the other end is closed and whose one end is communicated with the outlet of the filtration water. A ballast water producing method using the ballast water producing apparatus according to claim 7,
A preparation step of discharging the fluid from the discharge port together with the raw water through the filtration unit in a state in which the supply of the filtration water from the filter medium to the ballast tank and the supply of the fluid to the filter medium are stopped,
A filtration step of supplying raw water to the filtration unit and sending filtered water to the filtrate discharge port in a state in which the raw water is discharged from the filter medium and the fluid supply to the filter medium is stopped,
The raw water is supplied to the filter material while the supply of the filtered water to the ballast tank is stopped and the fluid is supplied to the filter material from the filtered water side and the fluid is discharged together with the raw water from the discharge port to the outside of the ship Backwash process
Wherein the ballast water is discharged from the ballast water tank.

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